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linux/fs/btrfs/volumes.c
Boris Burkov 70958a949d btrfs: do not clear read-only when adding sprout device 
If you follow the seed/sprout wiki, it suggests the following workflow:

btrfstune -S 1 seed_dev
mount seed_dev mnt
btrfs device add sprout_dev
mount -o remount,rw mnt

The first mount mounts the FS readonly, which results in not setting
BTRFS_FS_OPEN, and setting the readonly bit on the sb. The device add
somewhat surprisingly clears the readonly bit on the sb (though the
mount is still practically readonly, from the users perspective...).
Finally, the remount checks the readonly bit on the sb against the flag
and sees no change, so it does not run the code intended to run on
ro->rw transitions, leaving BTRFS_FS_OPEN unset.

As a result, when the cleaner_kthread runs, it sees no BTRFS_FS_OPEN and
does no work. This results in leaking deleted snapshots until we run out
of space.

I propose fixing it at the first departure from what feels reasonable:
when we clear the readonly bit on the sb during device add.

A new fstest I have written reproduces the bug and confirms the fix.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-11-11 14:34:18 +01:00

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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2007 Oracle. All rights reserved.
*/
#include <linux/sched.h>
#include <linux/sched/mm.h>
#include <linux/slab.h>
#include <linux/ratelimit.h>
#include <linux/kthread.h>
#include <linux/semaphore.h>
#include <linux/uuid.h>
#include <linux/list_sort.h>
#include <linux/namei.h>
#include "misc.h"
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
#include "volumes.h"
#include "raid56.h"
#include "rcu-string.h"
#include "dev-replace.h"
#include "sysfs.h"
#include "tree-checker.h"
#include "space-info.h"
#include "block-group.h"
#include "discard.h"
#include "zoned.h"
#include "fs.h"
#include "accessors.h"
#include "uuid-tree.h"
#include "ioctl.h"
#include "relocation.h"
#include "scrub.h"
#include "super.h"
#include "raid-stripe-tree.h"
#define BTRFS_BLOCK_GROUP_STRIPE_MASK (BTRFS_BLOCK_GROUP_RAID0 | \
BTRFS_BLOCK_GROUP_RAID10 | \
BTRFS_BLOCK_GROUP_RAID56_MASK)
struct btrfs_io_geometry {
u32 stripe_index;
u32 stripe_nr;
int mirror_num;
int num_stripes;
u64 stripe_offset;
u64 raid56_full_stripe_start;
int max_errors;
enum btrfs_map_op op;
};
const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
[BTRFS_RAID_RAID10] = {
.sub_stripes = 2,
.dev_stripes = 1,
.devs_max = 0, /* 0 == as many as possible */
.devs_min = 2,
.tolerated_failures = 1,
.devs_increment = 2,
.ncopies = 2,
.nparity = 0,
.raid_name = "raid10",
.bg_flag = BTRFS_BLOCK_GROUP_RAID10,
.mindev_error = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET,
},
[BTRFS_RAID_RAID1] = {
.sub_stripes = 1,
.dev_stripes = 1,
.devs_max = 2,
.devs_min = 2,
.tolerated_failures = 1,
.devs_increment = 2,
.ncopies = 2,
.nparity = 0,
.raid_name = "raid1",
.bg_flag = BTRFS_BLOCK_GROUP_RAID1,
.mindev_error = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET,
},
[BTRFS_RAID_RAID1C3] = {
.sub_stripes = 1,
.dev_stripes = 1,
.devs_max = 3,
.devs_min = 3,
.tolerated_failures = 2,
.devs_increment = 3,
.ncopies = 3,
.nparity = 0,
.raid_name = "raid1c3",
.bg_flag = BTRFS_BLOCK_GROUP_RAID1C3,
.mindev_error = BTRFS_ERROR_DEV_RAID1C3_MIN_NOT_MET,
},
[BTRFS_RAID_RAID1C4] = {
.sub_stripes = 1,
.dev_stripes = 1,
.devs_max = 4,
.devs_min = 4,
.tolerated_failures = 3,
.devs_increment = 4,
.ncopies = 4,
.nparity = 0,
.raid_name = "raid1c4",
.bg_flag = BTRFS_BLOCK_GROUP_RAID1C4,
.mindev_error = BTRFS_ERROR_DEV_RAID1C4_MIN_NOT_MET,
},
[BTRFS_RAID_DUP] = {
.sub_stripes = 1,
.dev_stripes = 2,
.devs_max = 1,
.devs_min = 1,
.tolerated_failures = 0,
.devs_increment = 1,
.ncopies = 2,
.nparity = 0,
.raid_name = "dup",
.bg_flag = BTRFS_BLOCK_GROUP_DUP,
.mindev_error = 0,
},
[BTRFS_RAID_RAID0] = {
.sub_stripes = 1,
.dev_stripes = 1,
.devs_max = 0,
.devs_min = 1,
.tolerated_failures = 0,
.devs_increment = 1,
.ncopies = 1,
.nparity = 0,
.raid_name = "raid0",
.bg_flag = BTRFS_BLOCK_GROUP_RAID0,
.mindev_error = 0,
},
[BTRFS_RAID_SINGLE] = {
.sub_stripes = 1,
.dev_stripes = 1,
.devs_max = 1,
.devs_min = 1,
.tolerated_failures = 0,
.devs_increment = 1,
.ncopies = 1,
.nparity = 0,
.raid_name = "single",
.bg_flag = 0,
.mindev_error = 0,
},
[BTRFS_RAID_RAID5] = {
.sub_stripes = 1,
.dev_stripes = 1,
.devs_max = 0,
.devs_min = 2,
.tolerated_failures = 1,
.devs_increment = 1,
.ncopies = 1,
.nparity = 1,
.raid_name = "raid5",
.bg_flag = BTRFS_BLOCK_GROUP_RAID5,
.mindev_error = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET,
},
[BTRFS_RAID_RAID6] = {
.sub_stripes = 1,
.dev_stripes = 1,
.devs_max = 0,
.devs_min = 3,
.tolerated_failures = 2,
.devs_increment = 1,
.ncopies = 1,
.nparity = 2,
.raid_name = "raid6",
.bg_flag = BTRFS_BLOCK_GROUP_RAID6,
.mindev_error = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET,
},
};
/*
* Convert block group flags (BTRFS_BLOCK_GROUP_*) to btrfs_raid_types, which
* can be used as index to access btrfs_raid_array[].
*/
enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags)
{
const u64 profile = (flags & BTRFS_BLOCK_GROUP_PROFILE_MASK);
if (!profile)
return BTRFS_RAID_SINGLE;
return BTRFS_BG_FLAG_TO_INDEX(profile);
}
const char *btrfs_bg_type_to_raid_name(u64 flags)
{
const int index = btrfs_bg_flags_to_raid_index(flags);
if (index >= BTRFS_NR_RAID_TYPES)
return NULL;
return btrfs_raid_array[index].raid_name;
}
int btrfs_nr_parity_stripes(u64 type)
{
enum btrfs_raid_types index = btrfs_bg_flags_to_raid_index(type);
return btrfs_raid_array[index].nparity;
}
/*
* Fill @buf with textual description of @bg_flags, no more than @size_buf
* bytes including terminating null byte.
*/
void btrfs_describe_block_groups(u64 bg_flags, char *buf, u32 size_buf)
{
int i;
int ret;
char *bp = buf;
u64 flags = bg_flags;
u32 size_bp = size_buf;
if (!flags) {
strcpy(bp, "NONE");
return;
}
#define DESCRIBE_FLAG(flag, desc) \
do { \
if (flags & (flag)) { \
ret = snprintf(bp, size_bp, "%s|", (desc)); \
if (ret < 0 || ret >= size_bp) \
goto out_overflow; \
size_bp -= ret; \
bp += ret; \
flags &= ~(flag); \
} \
} while (0)
DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_DATA, "data");
DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_SYSTEM, "system");
DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_METADATA, "metadata");
DESCRIBE_FLAG(BTRFS_AVAIL_ALLOC_BIT_SINGLE, "single");
for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
DESCRIBE_FLAG(btrfs_raid_array[i].bg_flag,
btrfs_raid_array[i].raid_name);
#undef DESCRIBE_FLAG
if (flags) {
ret = snprintf(bp, size_bp, "0x%llx|", flags);
size_bp -= ret;
}
if (size_bp < size_buf)
buf[size_buf - size_bp - 1] = '\0'; /* remove last | */
/*
* The text is trimmed, it's up to the caller to provide sufficiently
* large buffer
*/
out_overflow:;
}
static int init_first_rw_device(struct btrfs_trans_handle *trans);
static int btrfs_relocate_sys_chunks(struct btrfs_fs_info *fs_info);
static void btrfs_dev_stat_print_on_load(struct btrfs_device *device);
/*
* Device locking
* ==============
*
* There are several mutexes that protect manipulation of devices and low-level
* structures like chunks but not block groups, extents or files
*
* uuid_mutex (global lock)
* ------------------------
* protects the fs_uuids list that tracks all per-fs fs_devices, resulting from
* the SCAN_DEV ioctl registration or from mount either implicitly (the first
* device) or requested by the device= mount option
*
* the mutex can be very coarse and can cover long-running operations
*
* protects: updates to fs_devices counters like missing devices, rw devices,
* seeding, structure cloning, opening/closing devices at mount/umount time
*
* global::fs_devs - add, remove, updates to the global list
*
* does not protect: manipulation of the fs_devices::devices list in general
* but in mount context it could be used to exclude list modifications by eg.
* scan ioctl
*
* btrfs_device::name - renames (write side), read is RCU
*
* fs_devices::device_list_mutex (per-fs, with RCU)
* ------------------------------------------------
* protects updates to fs_devices::devices, ie. adding and deleting
*
* simple list traversal with read-only actions can be done with RCU protection
*
* may be used to exclude some operations from running concurrently without any
* modifications to the list (see write_all_supers)
*
* Is not required at mount and close times, because our device list is
* protected by the uuid_mutex at that point.
*
* balance_mutex
* -------------
* protects balance structures (status, state) and context accessed from
* several places (internally, ioctl)
*
* chunk_mutex
* -----------
* protects chunks, adding or removing during allocation, trim or when a new
* device is added/removed. Additionally it also protects post_commit_list of
* individual devices, since they can be added to the transaction's
* post_commit_list only with chunk_mutex held.
*
* cleaner_mutex
* -------------
* a big lock that is held by the cleaner thread and prevents running subvolume
* cleaning together with relocation or delayed iputs
*
*
* Lock nesting
* ============
*
* uuid_mutex
* device_list_mutex
* chunk_mutex
* balance_mutex
*
*
* Exclusive operations
* ====================
*
* Maintains the exclusivity of the following operations that apply to the
* whole filesystem and cannot run in parallel.
*
* - Balance (*)
* - Device add
* - Device remove
* - Device replace (*)
* - Resize
*
* The device operations (as above) can be in one of the following states:
*
* - Running state
* - Paused state
* - Completed state
*
* Only device operations marked with (*) can go into the Paused state for the
* following reasons:
*
* - ioctl (only Balance can be Paused through ioctl)
* - filesystem remounted as read-only
* - filesystem unmounted and mounted as read-only
* - system power-cycle and filesystem mounted as read-only
* - filesystem or device errors leading to forced read-only
*
* The status of exclusive operation is set and cleared atomically.
* During the course of Paused state, fs_info::exclusive_operation remains set.
* A device operation in Paused or Running state can be canceled or resumed
* either by ioctl (Balance only) or when remounted as read-write.
* The exclusive status is cleared when the device operation is canceled or
* completed.
*/
DEFINE_MUTEX(uuid_mutex);
static LIST_HEAD(fs_uuids);
struct list_head * __attribute_const__ btrfs_get_fs_uuids(void)
{
return &fs_uuids;
}
/*
* Allocate new btrfs_fs_devices structure identified by a fsid.
*
* @fsid: if not NULL, copy the UUID to fs_devices::fsid and to
* fs_devices::metadata_fsid
*
* Return a pointer to a new struct btrfs_fs_devices on success, or ERR_PTR().
* The returned struct is not linked onto any lists and can be destroyed with
* kfree() right away.
*/
static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid)
{
struct btrfs_fs_devices *fs_devs;
fs_devs = kzalloc(sizeof(*fs_devs), GFP_KERNEL);
if (!fs_devs)
return ERR_PTR(-ENOMEM);
mutex_init(&fs_devs->device_list_mutex);
INIT_LIST_HEAD(&fs_devs->devices);
INIT_LIST_HEAD(&fs_devs->alloc_list);
INIT_LIST_HEAD(&fs_devs->fs_list);
INIT_LIST_HEAD(&fs_devs->seed_list);
if (fsid) {
memcpy(fs_devs->fsid, fsid, BTRFS_FSID_SIZE);
memcpy(fs_devs->metadata_uuid, fsid, BTRFS_FSID_SIZE);
}
return fs_devs;
}
static void btrfs_free_device(struct btrfs_device *device)
{
WARN_ON(!list_empty(&device->post_commit_list));
rcu_string_free(device->name);
extent_io_tree_release(&device->alloc_state);
btrfs_destroy_dev_zone_info(device);
kfree(device);
}
static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
{
struct btrfs_device *device;
WARN_ON(fs_devices->opened);
while (!list_empty(&fs_devices->devices)) {
device = list_entry(fs_devices->devices.next,
struct btrfs_device, dev_list);
list_del(&device->dev_list);
btrfs_free_device(device);
}
kfree(fs_devices);
}
void __exit btrfs_cleanup_fs_uuids(void)
{
struct btrfs_fs_devices *fs_devices;
while (!list_empty(&fs_uuids)) {
fs_devices = list_entry(fs_uuids.next,
struct btrfs_fs_devices, fs_list);
list_del(&fs_devices->fs_list);
free_fs_devices(fs_devices);
}
}
static bool match_fsid_fs_devices(const struct btrfs_fs_devices *fs_devices,
const u8 *fsid, const u8 *metadata_fsid)
{
if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) != 0)
return false;
if (!metadata_fsid)
return true;
if (memcmp(metadata_fsid, fs_devices->metadata_uuid, BTRFS_FSID_SIZE) != 0)
return false;
return true;
}
static noinline struct btrfs_fs_devices *find_fsid(
const u8 *fsid, const u8 *metadata_fsid)
{
struct btrfs_fs_devices *fs_devices;
ASSERT(fsid);
/* Handle non-split brain cases */
list_for_each_entry(fs_devices, &fs_uuids, fs_list) {
if (match_fsid_fs_devices(fs_devices, fsid, metadata_fsid))
return fs_devices;
}
return NULL;
}
static int
btrfs_get_bdev_and_sb(const char *device_path, blk_mode_t flags, void *holder,
int flush, struct file **bdev_file,
struct btrfs_super_block **disk_super)
{
struct block_device *bdev;
int ret;
*bdev_file = bdev_file_open_by_path(device_path, flags, holder, NULL);
if (IS_ERR(*bdev_file)) {
ret = PTR_ERR(*bdev_file);
btrfs_err(NULL, "failed to open device for path %s with flags 0x%x: %d",
device_path, flags, ret);
goto error;
}
bdev = file_bdev(*bdev_file);
if (flush)
sync_blockdev(bdev);
if (holder) {
ret = set_blocksize(*bdev_file, BTRFS_BDEV_BLOCKSIZE);
if (ret) {
fput(*bdev_file);
goto error;
}
}
invalidate_bdev(bdev);
*disk_super = btrfs_read_dev_super(bdev);
if (IS_ERR(*disk_super)) {
ret = PTR_ERR(*disk_super);
fput(*bdev_file);
goto error;
}
return 0;
error:
*disk_super = NULL;
*bdev_file = NULL;
return ret;
}
/*
* Search and remove all stale devices (which are not mounted). When both
* inputs are NULL, it will search and release all stale devices.
*
* @devt: Optional. When provided will it release all unmounted devices
* matching this devt only.
* @skip_device: Optional. Will skip this device when searching for the stale
* devices.
*
* Return: 0 for success or if @devt is 0.
* -EBUSY if @devt is a mounted device.
* -ENOENT if @devt does not match any device in the list.
*/
static int btrfs_free_stale_devices(dev_t devt, struct btrfs_device *skip_device)
{
struct btrfs_fs_devices *fs_devices, *tmp_fs_devices;
struct btrfs_device *device, *tmp_device;
int ret;
bool freed = false;
lockdep_assert_held(&uuid_mutex);
/* Return good status if there is no instance of devt. */
ret = 0;
list_for_each_entry_safe(fs_devices, tmp_fs_devices, &fs_uuids, fs_list) {
mutex_lock(&fs_devices->device_list_mutex);
list_for_each_entry_safe(device, tmp_device,
&fs_devices->devices, dev_list) {
if (skip_device && skip_device == device)
continue;
if (devt && devt != device->devt)
continue;
if (fs_devices->opened) {
if (devt)
ret = -EBUSY;
break;
}
/* delete the stale device */
fs_devices->num_devices--;
list_del(&device->dev_list);
btrfs_free_device(device);
freed = true;
}
mutex_unlock(&fs_devices->device_list_mutex);
if (fs_devices->num_devices == 0) {
btrfs_sysfs_remove_fsid(fs_devices);
list_del(&fs_devices->fs_list);
free_fs_devices(fs_devices);
}
}
/* If there is at least one freed device return 0. */
if (freed)
return 0;
return ret;
}
static struct btrfs_fs_devices *find_fsid_by_device(
struct btrfs_super_block *disk_super,
dev_t devt, bool *same_fsid_diff_dev)
{
struct btrfs_fs_devices *fsid_fs_devices;
struct btrfs_fs_devices *devt_fs_devices;
const bool has_metadata_uuid = (btrfs_super_incompat_flags(disk_super) &
BTRFS_FEATURE_INCOMPAT_METADATA_UUID);
bool found_by_devt = false;
/* Find the fs_device by the usual method, if found use it. */
fsid_fs_devices = find_fsid(disk_super->fsid,
has_metadata_uuid ? disk_super->metadata_uuid : NULL);
/* The temp_fsid feature is supported only with single device filesystem. */
if (btrfs_super_num_devices(disk_super) != 1)
return fsid_fs_devices;
/*
* A seed device is an integral component of the sprout device, which
* functions as a multi-device filesystem. So, temp-fsid feature is
* not supported.
*/
if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING)
return fsid_fs_devices;
/* Try to find a fs_devices by matching devt. */
list_for_each_entry(devt_fs_devices, &fs_uuids, fs_list) {
struct btrfs_device *device;
list_for_each_entry(device, &devt_fs_devices->devices, dev_list) {
if (device->devt == devt) {
found_by_devt = true;
break;
}
}
if (found_by_devt)
break;
}
if (found_by_devt) {
/* Existing device. */
if (fsid_fs_devices == NULL) {
if (devt_fs_devices->opened == 0) {
/* Stale device. */
return NULL;
} else {
/* temp_fsid is mounting a subvol. */
return devt_fs_devices;
}
} else {
/* Regular or temp_fsid device mounting a subvol. */
return devt_fs_devices;
}
} else {
/* New device. */
if (fsid_fs_devices == NULL) {
return NULL;
} else {
/* sb::fsid is already used create a new temp_fsid. */
*same_fsid_diff_dev = true;
return NULL;
}
}
/* Not reached. */
}
/*
* This is only used on mount, and we are protected from competing things
* messing with our fs_devices by the uuid_mutex, thus we do not need the
* fs_devices->device_list_mutex here.
*/
static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices,
struct btrfs_device *device, blk_mode_t flags,
void *holder)
{
struct file *bdev_file;
struct btrfs_super_block *disk_super;
u64 devid;
int ret;
if (device->bdev)
return -EINVAL;
if (!device->name)
return -EINVAL;
ret = btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1,
&bdev_file, &disk_super);
if (ret)
return ret;
devid = btrfs_stack_device_id(&disk_super->dev_item);
if (devid != device->devid)
goto error_free_page;
if (memcmp(device->uuid, disk_super->dev_item.uuid, BTRFS_UUID_SIZE))
goto error_free_page;
device->generation = btrfs_super_generation(disk_super);
if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) {
if (btrfs_super_incompat_flags(disk_super) &
BTRFS_FEATURE_INCOMPAT_METADATA_UUID) {
pr_err(
"BTRFS: Invalid seeding and uuid-changed device detected\n");
goto error_free_page;
}
clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
fs_devices->seeding = true;
} else {
if (bdev_read_only(file_bdev(bdev_file)))
clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
else
set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
}
if (!bdev_nonrot(file_bdev(bdev_file)))
fs_devices->rotating = true;
if (bdev_max_discard_sectors(file_bdev(bdev_file)))
fs_devices->discardable = true;
device->bdev_file = bdev_file;
device->bdev = file_bdev(bdev_file);
clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
if (device->devt != device->bdev->bd_dev) {
btrfs_warn(NULL,
"device %s maj:min changed from %d:%d to %d:%d",
device->name->str, MAJOR(device->devt),
MINOR(device->devt), MAJOR(device->bdev->bd_dev),
MINOR(device->bdev->bd_dev));
device->devt = device->bdev->bd_dev;
}
fs_devices->open_devices++;
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
device->devid != BTRFS_DEV_REPLACE_DEVID) {
fs_devices->rw_devices++;
list_add_tail(&device->dev_alloc_list, &fs_devices->alloc_list);
}
btrfs_release_disk_super(disk_super);
return 0;
error_free_page:
btrfs_release_disk_super(disk_super);
fput(bdev_file);
return -EINVAL;
}
const u8 *btrfs_sb_fsid_ptr(const struct btrfs_super_block *sb)
{
bool has_metadata_uuid = (btrfs_super_incompat_flags(sb) &
BTRFS_FEATURE_INCOMPAT_METADATA_UUID);
return has_metadata_uuid ? sb->metadata_uuid : sb->fsid;
}
/*
* We can have very weird soft links passed in.
* One example is "/proc/self/fd/<fd>", which can be a soft link to
* a block device.
*
* But it's never a good idea to use those weird names.
* Here we check if the path (not following symlinks) is a good one inside
* "/dev/".
*/
static bool is_good_dev_path(const char *dev_path)
{
struct path path = { .mnt = NULL, .dentry = NULL };
char *path_buf = NULL;
char *resolved_path;
bool is_good = false;
int ret;
if (!dev_path)
goto out;
path_buf = kmalloc(PATH_MAX, GFP_KERNEL);
if (!path_buf)
goto out;
/*
* Do not follow soft link, just check if the original path is inside
* "/dev/".
*/
ret = kern_path(dev_path, 0, &path);
if (ret)
goto out;
resolved_path = d_path(&path, path_buf, PATH_MAX);
if (IS_ERR(resolved_path))
goto out;
if (strncmp(resolved_path, "/dev/", strlen("/dev/")))
goto out;
is_good = true;
out:
kfree(path_buf);
path_put(&path);
return is_good;
}
static int get_canonical_dev_path(const char *dev_path, char *canonical)
{
struct path path = { .mnt = NULL, .dentry = NULL };
char *path_buf = NULL;
char *resolved_path;
int ret;
if (!dev_path) {
ret = -EINVAL;
goto out;
}
path_buf = kmalloc(PATH_MAX, GFP_KERNEL);
if (!path_buf) {
ret = -ENOMEM;
goto out;
}
ret = kern_path(dev_path, LOOKUP_FOLLOW, &path);
if (ret)
goto out;
resolved_path = d_path(&path, path_buf, PATH_MAX);
ret = strscpy(canonical, resolved_path, PATH_MAX);
out:
kfree(path_buf);
path_put(&path);
return ret;
}
static bool is_same_device(struct btrfs_device *device, const char *new_path)
{
struct path old = { .mnt = NULL, .dentry = NULL };
struct path new = { .mnt = NULL, .dentry = NULL };
char *old_path = NULL;
bool is_same = false;
int ret;
if (!device->name)
goto out;
old_path = kzalloc(PATH_MAX, GFP_NOFS);
if (!old_path)
goto out;
rcu_read_lock();
ret = strscpy(old_path, rcu_str_deref(device->name), PATH_MAX);
rcu_read_unlock();
if (ret < 0)
goto out;
ret = kern_path(old_path, LOOKUP_FOLLOW, &old);
if (ret)
goto out;
ret = kern_path(new_path, LOOKUP_FOLLOW, &new);
if (ret)
goto out;
if (path_equal(&old, &new))
is_same = true;
out:
kfree(old_path);
path_put(&old);
path_put(&new);
return is_same;
}
/*
* Add new device to list of registered devices
*
* Returns:
* device pointer which was just added or updated when successful
* error pointer when failed
*/
static noinline struct btrfs_device *device_list_add(const char *path,
struct btrfs_super_block *disk_super,
bool *new_device_added)
{
struct btrfs_device *device;
struct btrfs_fs_devices *fs_devices = NULL;
struct rcu_string *name;
u64 found_transid = btrfs_super_generation(disk_super);
u64 devid = btrfs_stack_device_id(&disk_super->dev_item);
dev_t path_devt;
int error;
bool same_fsid_diff_dev = false;
bool has_metadata_uuid = (btrfs_super_incompat_flags(disk_super) &
BTRFS_FEATURE_INCOMPAT_METADATA_UUID);
if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_CHANGING_FSID_V2) {
btrfs_err(NULL,
"device %s has incomplete metadata_uuid change, please use btrfstune to complete",
path);
return ERR_PTR(-EAGAIN);
}
error = lookup_bdev(path, &path_devt);
if (error) {
btrfs_err(NULL, "failed to lookup block device for path %s: %d",
path, error);
return ERR_PTR(error);
}
fs_devices = find_fsid_by_device(disk_super, path_devt, &same_fsid_diff_dev);
if (!fs_devices) {
fs_devices = alloc_fs_devices(disk_super->fsid);
if (IS_ERR(fs_devices))
return ERR_CAST(fs_devices);
if (has_metadata_uuid)
memcpy(fs_devices->metadata_uuid,
disk_super->metadata_uuid, BTRFS_FSID_SIZE);
if (same_fsid_diff_dev) {
generate_random_uuid(fs_devices->fsid);
fs_devices->temp_fsid = true;
pr_info("BTRFS: device %s (%d:%d) using temp-fsid %pU\n",
path, MAJOR(path_devt), MINOR(path_devt),
fs_devices->fsid);
}
mutex_lock(&fs_devices->device_list_mutex);
list_add(&fs_devices->fs_list, &fs_uuids);
device = NULL;
} else {
struct btrfs_dev_lookup_args args = {
.devid = devid,
.uuid = disk_super->dev_item.uuid,
};
mutex_lock(&fs_devices->device_list_mutex);
device = btrfs_find_device(fs_devices, &args);
if (found_transid > fs_devices->latest_generation) {
memcpy(fs_devices->fsid, disk_super->fsid,
BTRFS_FSID_SIZE);
memcpy(fs_devices->metadata_uuid,
btrfs_sb_fsid_ptr(disk_super), BTRFS_FSID_SIZE);
}
}
if (!device) {
unsigned int nofs_flag;
if (fs_devices->opened) {
btrfs_err(NULL,
"device %s (%d:%d) belongs to fsid %pU, and the fs is already mounted, scanned by %s (%d)",
path, MAJOR(path_devt), MINOR(path_devt),
fs_devices->fsid, current->comm,
task_pid_nr(current));
mutex_unlock(&fs_devices->device_list_mutex);
return ERR_PTR(-EBUSY);
}
nofs_flag = memalloc_nofs_save();
device = btrfs_alloc_device(NULL, &devid,
disk_super->dev_item.uuid, path);
memalloc_nofs_restore(nofs_flag);
if (IS_ERR(device)) {
mutex_unlock(&fs_devices->device_list_mutex);
/* we can safely leave the fs_devices entry around */
return device;
}
device->devt = path_devt;
list_add_rcu(&device->dev_list, &fs_devices->devices);
fs_devices->num_devices++;
device->fs_devices = fs_devices;
*new_device_added = true;
if (disk_super->label[0])
pr_info(
"BTRFS: device label %s devid %llu transid %llu %s (%d:%d) scanned by %s (%d)\n",
disk_super->label, devid, found_transid, path,
MAJOR(path_devt), MINOR(path_devt),
current->comm, task_pid_nr(current));
else
pr_info(
"BTRFS: device fsid %pU devid %llu transid %llu %s (%d:%d) scanned by %s (%d)\n",
disk_super->fsid, devid, found_transid, path,
MAJOR(path_devt), MINOR(path_devt),
current->comm, task_pid_nr(current));
} else if (!device->name || !is_same_device(device, path)) {
/*
* When FS is already mounted.
* 1. If you are here and if the device->name is NULL that
* means this device was missing at time of FS mount.
* 2. If you are here and if the device->name is different
* from 'path' that means either
* a. The same device disappeared and reappeared with
* different name. or
* b. The missing-disk-which-was-replaced, has
* reappeared now.
*
* We must allow 1 and 2a above. But 2b would be a spurious
* and unintentional.
*
* Further in case of 1 and 2a above, the disk at 'path'
* would have missed some transaction when it was away and
* in case of 2a the stale bdev has to be updated as well.
* 2b must not be allowed at all time.
*/
/*
* For now, we do allow update to btrfs_fs_device through the
* btrfs dev scan cli after FS has been mounted. We're still
* tracking a problem where systems fail mount by subvolume id
* when we reject replacement on a mounted FS.
*/
if (!fs_devices->opened && found_transid < device->generation) {
/*
* That is if the FS is _not_ mounted and if you
* are here, that means there is more than one
* disk with same uuid and devid.We keep the one
* with larger generation number or the last-in if
* generation are equal.
*/
mutex_unlock(&fs_devices->device_list_mutex);
btrfs_err(NULL,
"device %s already registered with a higher generation, found %llu expect %llu",
path, found_transid, device->generation);
return ERR_PTR(-EEXIST);
}
/*
* We are going to replace the device path for a given devid,
* make sure it's the same device if the device is mounted
*
* NOTE: the device->fs_info may not be reliable here so pass
* in a NULL to message helpers instead. This avoids a possible
* use-after-free when the fs_info and fs_info->sb are already
* torn down.
*/
if (device->bdev) {
if (device->devt != path_devt) {
mutex_unlock(&fs_devices->device_list_mutex);
btrfs_warn_in_rcu(NULL,
"duplicate device %s devid %llu generation %llu scanned by %s (%d)",
path, devid, found_transid,
current->comm,
task_pid_nr(current));
return ERR_PTR(-EEXIST);
}
btrfs_info_in_rcu(NULL,
"devid %llu device path %s changed to %s scanned by %s (%d)",
devid, btrfs_dev_name(device),
path, current->comm,
task_pid_nr(current));
}
name = rcu_string_strdup(path, GFP_NOFS);
if (!name) {
mutex_unlock(&fs_devices->device_list_mutex);
return ERR_PTR(-ENOMEM);
}
rcu_string_free(device->name);
rcu_assign_pointer(device->name, name);
if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) {
fs_devices->missing_devices--;
clear_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
}
device->devt = path_devt;
}
/*
* Unmount does not free the btrfs_device struct but would zero
* generation along with most of the other members. So just update
* it back. We need it to pick the disk with largest generation
* (as above).
*/
if (!fs_devices->opened) {
device->generation = found_transid;
fs_devices->latest_generation = max_t(u64, found_transid,
fs_devices->latest_generation);
}
fs_devices->total_devices = btrfs_super_num_devices(disk_super);
mutex_unlock(&fs_devices->device_list_mutex);
return device;
}
static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
{
struct btrfs_fs_devices *fs_devices;
struct btrfs_device *device;
struct btrfs_device *orig_dev;
int ret = 0;
lockdep_assert_held(&uuid_mutex);
fs_devices = alloc_fs_devices(orig->fsid);
if (IS_ERR(fs_devices))
return fs_devices;
fs_devices->total_devices = orig->total_devices;
list_for_each_entry(orig_dev, &orig->devices, dev_list) {
const char *dev_path = NULL;
/*
* This is ok to do without RCU read locked because we hold the
* uuid mutex so nothing we touch in here is going to disappear.
*/
if (orig_dev->name)
dev_path = orig_dev->name->str;
device = btrfs_alloc_device(NULL, &orig_dev->devid,
orig_dev->uuid, dev_path);
if (IS_ERR(device)) {
ret = PTR_ERR(device);
goto error;
}
if (orig_dev->zone_info) {
struct btrfs_zoned_device_info *zone_info;
zone_info = btrfs_clone_dev_zone_info(orig_dev);
if (!zone_info) {
btrfs_free_device(device);
ret = -ENOMEM;
goto error;
}
device->zone_info = zone_info;
}
list_add(&device->dev_list, &fs_devices->devices);
device->fs_devices = fs_devices;
fs_devices->num_devices++;
}
return fs_devices;
error:
free_fs_devices(fs_devices);
return ERR_PTR(ret);
}
static void __btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices,
struct btrfs_device **latest_dev)
{
struct btrfs_device *device, *next;
/* This is the initialized path, it is safe to release the devices. */
list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
if (test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state)) {
if (!test_bit(BTRFS_DEV_STATE_REPLACE_TGT,
&device->dev_state) &&
!test_bit(BTRFS_DEV_STATE_MISSING,
&device->dev_state) &&
(!*latest_dev ||
device->generation > (*latest_dev)->generation)) {
*latest_dev = device;
}
continue;
}
/*
* We have already validated the presence of BTRFS_DEV_REPLACE_DEVID,
* in btrfs_init_dev_replace() so just continue.
*/
if (device->devid == BTRFS_DEV_REPLACE_DEVID)
continue;
if (device->bdev_file) {
fput(device->bdev_file);
device->bdev = NULL;
device->bdev_file = NULL;
fs_devices->open_devices--;
}
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
list_del_init(&device->dev_alloc_list);
clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
fs_devices->rw_devices--;
}
list_del_init(&device->dev_list);
fs_devices->num_devices--;
btrfs_free_device(device);
}
}
/*
* After we have read the system tree and know devids belonging to this
* filesystem, remove the device which does not belong there.
*/
void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices)
{
struct btrfs_device *latest_dev = NULL;
struct btrfs_fs_devices *seed_dev;
mutex_lock(&uuid_mutex);
__btrfs_free_extra_devids(fs_devices, &latest_dev);
list_for_each_entry(seed_dev, &fs_devices->seed_list, seed_list)
__btrfs_free_extra_devids(seed_dev, &latest_dev);
fs_devices->latest_dev = latest_dev;
mutex_unlock(&uuid_mutex);
}
static void btrfs_close_bdev(struct btrfs_device *device)
{
if (!device->bdev)
return;
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
sync_blockdev(device->bdev);
invalidate_bdev(device->bdev);
}
fput(device->bdev_file);
}
static void btrfs_close_one_device(struct btrfs_device *device)
{
struct btrfs_fs_devices *fs_devices = device->fs_devices;
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
device->devid != BTRFS_DEV_REPLACE_DEVID) {
list_del_init(&device->dev_alloc_list);
fs_devices->rw_devices--;
}
if (device->devid == BTRFS_DEV_REPLACE_DEVID)
clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) {
clear_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
fs_devices->missing_devices--;
}
btrfs_close_bdev(device);
if (device->bdev) {
fs_devices->open_devices--;
device->bdev = NULL;
device->bdev_file = NULL;
}
clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
btrfs_destroy_dev_zone_info(device);
device->fs_info = NULL;
atomic_set(&device->dev_stats_ccnt, 0);
extent_io_tree_release(&device->alloc_state);
/*
* Reset the flush error record. We might have a transient flush error
* in this mount, and if so we aborted the current transaction and set
* the fs to an error state, guaranteeing no super blocks can be further
* committed. However that error might be transient and if we unmount the
* filesystem and mount it again, we should allow the mount to succeed
* (btrfs_check_rw_degradable() should not fail) - if after mounting the
* filesystem again we still get flush errors, then we will again abort
* any transaction and set the error state, guaranteeing no commits of
* unsafe super blocks.
*/
device->last_flush_error = 0;
/* Verify the device is back in a pristine state */
WARN_ON(test_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state));
WARN_ON(test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state));
WARN_ON(!list_empty(&device->dev_alloc_list));
WARN_ON(!list_empty(&device->post_commit_list));
}
static void close_fs_devices(struct btrfs_fs_devices *fs_devices)
{
struct btrfs_device *device, *tmp;
lockdep_assert_held(&uuid_mutex);
if (--fs_devices->opened > 0)
return;
list_for_each_entry_safe(device, tmp, &fs_devices->devices, dev_list)
btrfs_close_one_device(device);
WARN_ON(fs_devices->open_devices);
WARN_ON(fs_devices->rw_devices);
fs_devices->opened = 0;
fs_devices->seeding = false;
fs_devices->fs_info = NULL;
}
void btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
{
LIST_HEAD(list);
struct btrfs_fs_devices *tmp;
mutex_lock(&uuid_mutex);
close_fs_devices(fs_devices);
if (!fs_devices->opened) {
list_splice_init(&fs_devices->seed_list, &list);
/*
* If the struct btrfs_fs_devices is not assembled with any
* other device, it can be re-initialized during the next mount
* without the needing device-scan step. Therefore, it can be
* fully freed.
*/
if (fs_devices->num_devices == 1) {
list_del(&fs_devices->fs_list);
free_fs_devices(fs_devices);
}
}
list_for_each_entry_safe(fs_devices, tmp, &list, seed_list) {
close_fs_devices(fs_devices);
list_del(&fs_devices->seed_list);
free_fs_devices(fs_devices);
}
mutex_unlock(&uuid_mutex);
}
static int open_fs_devices(struct btrfs_fs_devices *fs_devices,
blk_mode_t flags, void *holder)
{
struct btrfs_device *device;
struct btrfs_device *latest_dev = NULL;
struct btrfs_device *tmp_device;
int ret = 0;
list_for_each_entry_safe(device, tmp_device, &fs_devices->devices,
dev_list) {
int ret2;
ret2 = btrfs_open_one_device(fs_devices, device, flags, holder);
if (ret2 == 0 &&
(!latest_dev || device->generation > latest_dev->generation)) {
latest_dev = device;
} else if (ret2 == -ENODATA) {
fs_devices->num_devices--;
list_del(&device->dev_list);
btrfs_free_device(device);
}
if (ret == 0 && ret2 != 0)
ret = ret2;
}
if (fs_devices->open_devices == 0) {
if (ret)
return ret;
return -EINVAL;
}
fs_devices->opened = 1;
fs_devices->latest_dev = latest_dev;
fs_devices->total_rw_bytes = 0;
fs_devices->chunk_alloc_policy = BTRFS_CHUNK_ALLOC_REGULAR;
fs_devices->read_policy = BTRFS_READ_POLICY_PID;
return 0;
}
static int devid_cmp(void *priv, const struct list_head *a,
const struct list_head *b)
{
const struct btrfs_device *dev1, *dev2;
dev1 = list_entry(a, struct btrfs_device, dev_list);
dev2 = list_entry(b, struct btrfs_device, dev_list);
if (dev1->devid < dev2->devid)
return -1;
else if (dev1->devid > dev2->devid)
return 1;
return 0;
}
int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
blk_mode_t flags, void *holder)
{
int ret;
lockdep_assert_held(&uuid_mutex);
/*
* The device_list_mutex cannot be taken here in case opening the
* underlying device takes further locks like open_mutex.
*
* We also don't need the lock here as this is called during mount and
* exclusion is provided by uuid_mutex
*/
if (fs_devices->opened) {
fs_devices->opened++;
ret = 0;
} else {
list_sort(NULL, &fs_devices->devices, devid_cmp);
ret = open_fs_devices(fs_devices, flags, holder);
}
return ret;
}
void btrfs_release_disk_super(struct btrfs_super_block *super)
{
struct page *page = virt_to_page(super);
put_page(page);
}
static struct btrfs_super_block *btrfs_read_disk_super(struct block_device *bdev,
u64 bytenr, u64 bytenr_orig)
{
struct btrfs_super_block *disk_super;
struct page *page;
void *p;
pgoff_t index;
/* make sure our super fits in the device */
if (bytenr + PAGE_SIZE >= bdev_nr_bytes(bdev))
return ERR_PTR(-EINVAL);
/* make sure our super fits in the page */
if (sizeof(*disk_super) > PAGE_SIZE)
return ERR_PTR(-EINVAL);
/* make sure our super doesn't straddle pages on disk */
index = bytenr >> PAGE_SHIFT;
if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_SHIFT != index)
return ERR_PTR(-EINVAL);
/* pull in the page with our super */
page = read_cache_page_gfp(bdev->bd_mapping, index, GFP_KERNEL);
if (IS_ERR(page))
return ERR_CAST(page);
p = page_address(page);
/* align our pointer to the offset of the super block */
disk_super = p + offset_in_page(bytenr);
if (btrfs_super_bytenr(disk_super) != bytenr_orig ||
btrfs_super_magic(disk_super) != BTRFS_MAGIC) {
btrfs_release_disk_super(p);
return ERR_PTR(-EINVAL);
}
if (disk_super->label[0] && disk_super->label[BTRFS_LABEL_SIZE - 1])
disk_super->label[BTRFS_LABEL_SIZE - 1] = 0;
return disk_super;
}
int btrfs_forget_devices(dev_t devt)
{
int ret;
mutex_lock(&uuid_mutex);
ret = btrfs_free_stale_devices(devt, NULL);
mutex_unlock(&uuid_mutex);
return ret;
}
static bool btrfs_skip_registration(struct btrfs_super_block *disk_super,
const char *path, dev_t devt,
bool mount_arg_dev)
{
struct btrfs_fs_devices *fs_devices;
/*
* Do not skip device registration for mounted devices with matching
* maj:min but different paths. Booting without initrd relies on
* /dev/root initially, later replaced with the actual root device.
* A successful scan ensures grub2-probe selects the correct device.
*/
list_for_each_entry(fs_devices, &fs_uuids, fs_list) {
struct btrfs_device *device;
mutex_lock(&fs_devices->device_list_mutex);
if (!fs_devices->opened) {
mutex_unlock(&fs_devices->device_list_mutex);
continue;
}
list_for_each_entry(device, &fs_devices->devices, dev_list) {
if (device->bdev && (device->bdev->bd_dev == devt) &&
strcmp(device->name->str, path) != 0) {
mutex_unlock(&fs_devices->device_list_mutex);
/* Do not skip registration. */
return false;
}
}
mutex_unlock(&fs_devices->device_list_mutex);
}
if (!mount_arg_dev && btrfs_super_num_devices(disk_super) == 1 &&
!(btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING))
return true;
return false;
}
/*
* Look for a btrfs signature on a device. This may be called out of the mount path
* and we are not allowed to call set_blocksize during the scan. The superblock
* is read via pagecache.
*
* With @mount_arg_dev it's a scan during mount time that will always register
* the device or return an error. Multi-device and seeding devices are registered
* in both cases.
*/
struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags,
bool mount_arg_dev)
{
struct btrfs_super_block *disk_super;
bool new_device_added = false;
struct btrfs_device *device = NULL;
struct file *bdev_file;
char *canonical_path = NULL;
u64 bytenr;
dev_t devt;
int ret;
lockdep_assert_held(&uuid_mutex);
if (!is_good_dev_path(path)) {
canonical_path = kmalloc(PATH_MAX, GFP_KERNEL);
if (canonical_path) {
ret = get_canonical_dev_path(path, canonical_path);
if (ret < 0) {
kfree(canonical_path);
canonical_path = NULL;
}
}
}
/*
* Avoid an exclusive open here, as the systemd-udev may initiate the
* device scan which may race with the user's mount or mkfs command,
* resulting in failure.
* Since the device scan is solely for reading purposes, there is no
* need for an exclusive open. Additionally, the devices are read again
* during the mount process. It is ok to get some inconsistent
* values temporarily, as the device paths of the fsid are the only
* required information for assembling the volume.
*/
bdev_file = bdev_file_open_by_path(path, flags, NULL, NULL);
if (IS_ERR(bdev_file))
return ERR_CAST(bdev_file);
/*
* We would like to check all the super blocks, but doing so would
* allow a mount to succeed after a mkfs from a different filesystem.
* Currently, recovery from a bad primary btrfs superblock is done
* using the userspace command 'btrfs check --super'.
*/
ret = btrfs_sb_log_location_bdev(file_bdev(bdev_file), 0, READ, &bytenr);
if (ret) {
device = ERR_PTR(ret);
goto error_bdev_put;
}
disk_super = btrfs_read_disk_super(file_bdev(bdev_file), bytenr,
btrfs_sb_offset(0));
if (IS_ERR(disk_super)) {
device = ERR_CAST(disk_super);
goto error_bdev_put;
}
devt = file_bdev(bdev_file)->bd_dev;
if (btrfs_skip_registration(disk_super, path, devt, mount_arg_dev)) {
pr_debug("BTRFS: skip registering single non-seed device %s (%d:%d)\n",
path, MAJOR(devt), MINOR(devt));
btrfs_free_stale_devices(devt, NULL);
device = NULL;
goto free_disk_super;
}
device = device_list_add(canonical_path ? : path, disk_super,
&new_device_added);
if (!IS_ERR(device) && new_device_added)
btrfs_free_stale_devices(device->devt, device);
free_disk_super:
btrfs_release_disk_super(disk_super);
error_bdev_put:
fput(bdev_file);
kfree(canonical_path);
return device;
}
/*
* Try to find a chunk that intersects [start, start + len] range and when one
* such is found, record the end of it in *start
*/
static bool contains_pending_extent(struct btrfs_device *device, u64 *start,
u64 len)
{
u64 physical_start, physical_end;
lockdep_assert_held(&device->fs_info->chunk_mutex);
if (find_first_extent_bit(&device->alloc_state, *start,
&physical_start, &physical_end,
CHUNK_ALLOCATED, NULL)) {
if (in_range(physical_start, *start, len) ||
in_range(*start, physical_start,
physical_end + 1 - physical_start)) {
*start = physical_end + 1;
return true;
}
}
return false;
}
static u64 dev_extent_search_start(struct btrfs_device *device)
{
switch (device->fs_devices->chunk_alloc_policy) {
case BTRFS_CHUNK_ALLOC_REGULAR:
return BTRFS_DEVICE_RANGE_RESERVED;
case BTRFS_CHUNK_ALLOC_ZONED:
/*
* We don't care about the starting region like regular
* allocator, because we anyway use/reserve the first two zones
* for superblock logging.
*/
return 0;
default:
BUG();
}
}
static bool dev_extent_hole_check_zoned(struct btrfs_device *device,
u64 *hole_start, u64 *hole_size,
u64 num_bytes)
{
u64 zone_size = device->zone_info->zone_size;
u64 pos;
int ret;
bool changed = false;
ASSERT(IS_ALIGNED(*hole_start, zone_size));
while (*hole_size > 0) {
pos = btrfs_find_allocatable_zones(device, *hole_start,
*hole_start + *hole_size,
num_bytes);
if (pos != *hole_start) {
*hole_size = *hole_start + *hole_size - pos;
*hole_start = pos;
changed = true;
if (*hole_size < num_bytes)
break;
}
ret = btrfs_ensure_empty_zones(device, pos, num_bytes);
/* Range is ensured to be empty */
if (!ret)
return changed;
/* Given hole range was invalid (outside of device) */
if (ret == -ERANGE) {
*hole_start += *hole_size;
*hole_size = 0;
return true;
}
*hole_start += zone_size;
*hole_size -= zone_size;
changed = true;
}
return changed;
}
/*
* Check if specified hole is suitable for allocation.
*
* @device: the device which we have the hole
* @hole_start: starting position of the hole
* @hole_size: the size of the hole
* @num_bytes: the size of the free space that we need
*
* This function may modify @hole_start and @hole_size to reflect the suitable
* position for allocation. Returns 1 if hole position is updated, 0 otherwise.
*/
static bool dev_extent_hole_check(struct btrfs_device *device, u64 *hole_start,
u64 *hole_size, u64 num_bytes)
{
bool changed = false;
u64 hole_end = *hole_start + *hole_size;
for (;;) {
/*
* Check before we set max_hole_start, otherwise we could end up
* sending back this offset anyway.
*/
if (contains_pending_extent(device, hole_start, *hole_size)) {
if (hole_end >= *hole_start)
*hole_size = hole_end - *hole_start;
else
*hole_size = 0;
changed = true;
}
switch (device->fs_devices->chunk_alloc_policy) {
case BTRFS_CHUNK_ALLOC_REGULAR:
/* No extra check */
break;
case BTRFS_CHUNK_ALLOC_ZONED:
if (dev_extent_hole_check_zoned(device, hole_start,
hole_size, num_bytes)) {
changed = true;
/*
* The changed hole can contain pending extent.
* Loop again to check that.
*/
continue;
}
break;
default:
BUG();
}
break;
}
return changed;
}
/*
* Find free space in the specified device.
*
* @device: the device which we search the free space in
* @num_bytes: the size of the free space that we need
* @search_start: the position from which to begin the search
* @start: store the start of the free space.
* @len: the size of the free space. that we find, or the size
* of the max free space if we don't find suitable free space
*
* This does a pretty simple search, the expectation is that it is called very
* infrequently and that a given device has a small number of extents.
*
* @start is used to store the start of the free space if we find. But if we
* don't find suitable free space, it will be used to store the start position
* of the max free space.
*
* @len is used to store the size of the free space that we find.
* But if we don't find suitable free space, it is used to store the size of
* the max free space.
*
* NOTE: This function will search *commit* root of device tree, and does extra
* check to ensure dev extents are not double allocated.
* This makes the function safe to allocate dev extents but may not report
* correct usable device space, as device extent freed in current transaction
* is not reported as available.
*/
static int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
u64 *start, u64 *len)
{
struct btrfs_fs_info *fs_info = device->fs_info;
struct btrfs_root *root = fs_info->dev_root;
struct btrfs_key key;
struct btrfs_dev_extent *dev_extent;
struct btrfs_path *path;
u64 search_start;
u64 hole_size;
u64 max_hole_start;
u64 max_hole_size = 0;
u64 extent_end;
u64 search_end = device->total_bytes;
int ret;
int slot;
struct extent_buffer *l;
search_start = dev_extent_search_start(device);
max_hole_start = search_start;
WARN_ON(device->zone_info &&
!IS_ALIGNED(num_bytes, device->zone_info->zone_size));
path = btrfs_alloc_path();
if (!path) {
ret = -ENOMEM;
goto out;
}
again:
if (search_start >= search_end ||
test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
ret = -ENOSPC;
goto out;
}
path->reada = READA_FORWARD;
path->search_commit_root = 1;
path->skip_locking = 1;
key.objectid = device->devid;
key.offset = search_start;
key.type = BTRFS_DEV_EXTENT_KEY;
ret = btrfs_search_backwards(root, &key, path);
if (ret < 0)
goto out;
while (search_start < search_end) {
l = path->nodes[0];
slot = path->slots[0];
if (slot >= btrfs_header_nritems(l)) {
ret = btrfs_next_leaf(root, path);
if (ret == 0)
continue;
if (ret < 0)
goto out;
break;
}
btrfs_item_key_to_cpu(l, &key, slot);
if (key.objectid < device->devid)
goto next;
if (key.objectid > device->devid)
break;
if (key.type != BTRFS_DEV_EXTENT_KEY)
goto next;
if (key.offset > search_end)
break;
if (key.offset > search_start) {
hole_size = key.offset - search_start;
dev_extent_hole_check(device, &search_start, &hole_size,
num_bytes);
if (hole_size > max_hole_size) {
max_hole_start = search_start;
max_hole_size = hole_size;
}
/*
* If this free space is greater than which we need,
* it must be the max free space that we have found
* until now, so max_hole_start must point to the start
* of this free space and the length of this free space
* is stored in max_hole_size. Thus, we return
* max_hole_start and max_hole_size and go back to the
* caller.
*/
if (hole_size >= num_bytes) {
ret = 0;
goto out;
}
}
dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
extent_end = key.offset + btrfs_dev_extent_length(l,
dev_extent);
if (extent_end > search_start)
search_start = extent_end;
next:
path->slots[0]++;
cond_resched();
}
/*
* At this point, search_start should be the end of
* allocated dev extents, and when shrinking the device,
* search_end may be smaller than search_start.
*/
if (search_end > search_start) {
hole_size = search_end - search_start;
if (dev_extent_hole_check(device, &search_start, &hole_size,
num_bytes)) {
btrfs_release_path(path);
goto again;
}
if (hole_size > max_hole_size) {
max_hole_start = search_start;
max_hole_size = hole_size;
}
}
/* See above. */
if (max_hole_size < num_bytes)
ret = -ENOSPC;
else
ret = 0;
ASSERT(max_hole_start + max_hole_size <= search_end);
out:
btrfs_free_path(path);
*start = max_hole_start;
if (len)
*len = max_hole_size;
return ret;
}
static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
struct btrfs_device *device,
u64 start, u64 *dev_extent_len)
{
struct btrfs_fs_info *fs_info = device->fs_info;
struct btrfs_root *root = fs_info->dev_root;
int ret;
struct btrfs_path *path;
struct btrfs_key key;
struct btrfs_key found_key;
struct extent_buffer *leaf = NULL;
struct btrfs_dev_extent *extent = NULL;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = device->devid;
key.offset = start;
key.type = BTRFS_DEV_EXTENT_KEY;
again:
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
if (ret > 0) {
ret = btrfs_previous_item(root, path, key.objectid,
BTRFS_DEV_EXTENT_KEY);
if (ret)
goto out;
leaf = path->nodes[0];
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
extent = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_dev_extent);
BUG_ON(found_key.offset > start || found_key.offset +
btrfs_dev_extent_length(leaf, extent) < start);
key = found_key;
btrfs_release_path(path);
goto again;
} else if (ret == 0) {
leaf = path->nodes[0];
extent = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_dev_extent);
} else {
goto out;
}
*dev_extent_len = btrfs_dev_extent_length(leaf, extent);
ret = btrfs_del_item(trans, root, path);
if (ret == 0)
set_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags);
out:
btrfs_free_path(path);
return ret;
}
static u64 find_next_chunk(struct btrfs_fs_info *fs_info)
{
struct rb_node *n;
u64 ret = 0;
read_lock(&fs_info->mapping_tree_lock);
n = rb_last(&fs_info->mapping_tree.rb_root);
if (n) {
struct btrfs_chunk_map *map;
map = rb_entry(n, struct btrfs_chunk_map, rb_node);
ret = map->start + map->chunk_len;
}
read_unlock(&fs_info->mapping_tree_lock);
return ret;
}
static noinline int find_next_devid(struct btrfs_fs_info *fs_info,
u64 *devid_ret)
{
int ret;
struct btrfs_key key;
struct btrfs_key found_key;
struct btrfs_path *path;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
key.type = BTRFS_DEV_ITEM_KEY;
key.offset = (u64)-1;
ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, path, 0, 0);
if (ret < 0)
goto error;
if (ret == 0) {
/* Corruption */
btrfs_err(fs_info, "corrupted chunk tree devid -1 matched");
ret = -EUCLEAN;
goto error;
}
ret = btrfs_previous_item(fs_info->chunk_root, path,
BTRFS_DEV_ITEMS_OBJECTID,
BTRFS_DEV_ITEM_KEY);
if (ret) {
*devid_ret = 1;
} else {
btrfs_item_key_to_cpu(path->nodes[0], &found_key,
path->slots[0]);
*devid_ret = found_key.offset + 1;
}
ret = 0;
error:
btrfs_free_path(path);
return ret;
}
/*
* the device information is stored in the chunk root
* the btrfs_device struct should be fully filled in
*/
static int btrfs_add_dev_item(struct btrfs_trans_handle *trans,
struct btrfs_device *device)
{
int ret;
struct btrfs_path *path;
struct btrfs_dev_item *dev_item;
struct extent_buffer *leaf;
struct btrfs_key key;
unsigned long ptr;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
key.type = BTRFS_DEV_ITEM_KEY;
key.offset = device->devid;
btrfs_reserve_chunk_metadata(trans, true);
ret = btrfs_insert_empty_item(trans, trans->fs_info->chunk_root, path,
&key, sizeof(*dev_item));
btrfs_trans_release_chunk_metadata(trans);
if (ret)
goto out;
leaf = path->nodes[0];
dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
btrfs_set_device_id(leaf, dev_item, device->devid);
btrfs_set_device_generation(leaf, dev_item, 0);
btrfs_set_device_type(leaf, dev_item, device->type);
btrfs_set_device_io_align(leaf, dev_item, device->io_align);
btrfs_set_device_io_width(leaf, dev_item, device->io_width);
btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
btrfs_set_device_total_bytes(leaf, dev_item,
btrfs_device_get_disk_total_bytes(device));
btrfs_set_device_bytes_used(leaf, dev_item,
btrfs_device_get_bytes_used(device));
btrfs_set_device_group(leaf, dev_item, 0);
btrfs_set_device_seek_speed(leaf, dev_item, 0);
btrfs_set_device_bandwidth(leaf, dev_item, 0);
btrfs_set_device_start_offset(leaf, dev_item, 0);
ptr = btrfs_device_uuid(dev_item);
write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
ptr = btrfs_device_fsid(dev_item);
write_extent_buffer(leaf, trans->fs_info->fs_devices->metadata_uuid,
ptr, BTRFS_FSID_SIZE);
btrfs_mark_buffer_dirty(trans, leaf);
ret = 0;
out:
btrfs_free_path(path);
return ret;
}
/*
* Function to update ctime/mtime for a given device path.
* Mainly used for ctime/mtime based probe like libblkid.
*
* We don't care about errors here, this is just to be kind to userspace.
*/
static void update_dev_time(const char *device_path)
{
struct path path;
int ret;
ret = kern_path(device_path, LOOKUP_FOLLOW, &path);
if (ret)
return;
inode_update_time(d_inode(path.dentry), S_MTIME | S_CTIME | S_VERSION);
path_put(&path);
}
static int btrfs_rm_dev_item(struct btrfs_trans_handle *trans,
struct btrfs_device *device)
{
struct btrfs_root *root = device->fs_info->chunk_root;
int ret;
struct btrfs_path *path;
struct btrfs_key key;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
key.type = BTRFS_DEV_ITEM_KEY;
key.offset = device->devid;
btrfs_reserve_chunk_metadata(trans, false);
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
btrfs_trans_release_chunk_metadata(trans);
if (ret) {
if (ret > 0)
ret = -ENOENT;
goto out;
}
ret = btrfs_del_item(trans, root, path);
out:
btrfs_free_path(path);
return ret;
}
/*
* Verify that @num_devices satisfies the RAID profile constraints in the whole
* filesystem. It's up to the caller to adjust that number regarding eg. device
* replace.
*/
static int btrfs_check_raid_min_devices(struct btrfs_fs_info *fs_info,
u64 num_devices)
{
u64 all_avail;
unsigned seq;
int i;
do {
seq = read_seqbegin(&fs_info->profiles_lock);
all_avail = fs_info->avail_data_alloc_bits |
fs_info->avail_system_alloc_bits |
fs_info->avail_metadata_alloc_bits;
} while (read_seqretry(&fs_info->profiles_lock, seq));
for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
if (!(all_avail & btrfs_raid_array[i].bg_flag))
continue;
if (num_devices < btrfs_raid_array[i].devs_min)
return btrfs_raid_array[i].mindev_error;
}
return 0;
}
static struct btrfs_device * btrfs_find_next_active_device(
struct btrfs_fs_devices *fs_devs, struct btrfs_device *device)
{
struct btrfs_device *next_device;
list_for_each_entry(next_device, &fs_devs->devices, dev_list) {
if (next_device != device &&
!test_bit(BTRFS_DEV_STATE_MISSING, &next_device->dev_state)
&& next_device->bdev)
return next_device;
}
return NULL;
}
/*
* Helper function to check if the given device is part of s_bdev / latest_dev
* and replace it with the provided or the next active device, in the context
* where this function called, there should be always be another device (or
* this_dev) which is active.
*/
void __cold btrfs_assign_next_active_device(struct btrfs_device *device,
struct btrfs_device *next_device)
{
struct btrfs_fs_info *fs_info = device->fs_info;
if (!next_device)
next_device = btrfs_find_next_active_device(fs_info->fs_devices,
device);
ASSERT(next_device);
if (fs_info->sb->s_bdev &&
(fs_info->sb->s_bdev == device->bdev))
fs_info->sb->s_bdev = next_device->bdev;
if (fs_info->fs_devices->latest_dev->bdev == device->bdev)
fs_info->fs_devices->latest_dev = next_device;
}
/*
* Return btrfs_fs_devices::num_devices excluding the device that's being
* currently replaced.
*/
static u64 btrfs_num_devices(struct btrfs_fs_info *fs_info)
{
u64 num_devices = fs_info->fs_devices->num_devices;
down_read(&fs_info->dev_replace.rwsem);
if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) {
ASSERT(num_devices > 1);
num_devices--;
}
up_read(&fs_info->dev_replace.rwsem);
return num_devices;
}
static void btrfs_scratch_superblock(struct btrfs_fs_info *fs_info,
struct block_device *bdev, int copy_num)
{
struct btrfs_super_block *disk_super;
const size_t len = sizeof(disk_super->magic);
const u64 bytenr = btrfs_sb_offset(copy_num);
int ret;
disk_super = btrfs_read_disk_super(bdev, bytenr, bytenr);
if (IS_ERR(disk_super))
return;
memset(&disk_super->magic, 0, len);
folio_mark_dirty(virt_to_folio(disk_super));
btrfs_release_disk_super(disk_super);
ret = sync_blockdev_range(bdev, bytenr, bytenr + len - 1);
if (ret)
btrfs_warn(fs_info, "error clearing superblock number %d (%d)",
copy_num, ret);
}
void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info, struct btrfs_device *device)
{
int copy_num;
struct block_device *bdev = device->bdev;
if (!bdev)
return;
for (copy_num = 0; copy_num < BTRFS_SUPER_MIRROR_MAX; copy_num++) {
if (bdev_is_zoned(bdev))
btrfs_reset_sb_log_zones(bdev, copy_num);
else
btrfs_scratch_superblock(fs_info, bdev, copy_num);
}
/* Notify udev that device has changed */
btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
/* Update ctime/mtime for device path for libblkid */
update_dev_time(device->name->str);
}
int btrfs_rm_device(struct btrfs_fs_info *fs_info,
struct btrfs_dev_lookup_args *args,
struct file **bdev_file)
{
struct btrfs_trans_handle *trans;
struct btrfs_device *device;
struct btrfs_fs_devices *cur_devices;
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
u64 num_devices;
int ret = 0;
if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
btrfs_err(fs_info, "device remove not supported on extent tree v2 yet");
return -EINVAL;
}
/*
* The device list in fs_devices is accessed without locks (neither
* uuid_mutex nor device_list_mutex) as it won't change on a mounted
* filesystem and another device rm cannot run.
*/
num_devices = btrfs_num_devices(fs_info);
ret = btrfs_check_raid_min_devices(fs_info, num_devices - 1);
if (ret)
return ret;
device = btrfs_find_device(fs_info->fs_devices, args);
if (!device) {
if (args->missing)
ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND;
else
ret = -ENOENT;
return ret;
}
if (btrfs_pinned_by_swapfile(fs_info, device)) {
btrfs_warn_in_rcu(fs_info,
"cannot remove device %s (devid %llu) due to active swapfile",
btrfs_dev_name(device), device->devid);
return -ETXTBSY;
}
if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state))
return BTRFS_ERROR_DEV_TGT_REPLACE;
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
fs_info->fs_devices->rw_devices == 1)
return BTRFS_ERROR_DEV_ONLY_WRITABLE;
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
mutex_lock(&fs_info->chunk_mutex);
list_del_init(&device->dev_alloc_list);
device->fs_devices->rw_devices--;
mutex_unlock(&fs_info->chunk_mutex);
}
ret = btrfs_shrink_device(device, 0);
if (ret)
goto error_undo;
trans = btrfs_start_transaction(fs_info->chunk_root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
goto error_undo;
}
ret = btrfs_rm_dev_item(trans, device);
if (ret) {
/* Any error in dev item removal is critical */
btrfs_crit(fs_info,
"failed to remove device item for devid %llu: %d",
device->devid, ret);
btrfs_abort_transaction(trans, ret);
btrfs_end_transaction(trans);
return ret;
}
clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
btrfs_scrub_cancel_dev(device);
/*
* the device list mutex makes sure that we don't change
* the device list while someone else is writing out all
* the device supers. Whoever is writing all supers, should
* lock the device list mutex before getting the number of
* devices in the super block (super_copy). Conversely,
* whoever updates the number of devices in the super block
* (super_copy) should hold the device list mutex.
*/
/*
* In normal cases the cur_devices == fs_devices. But in case
* of deleting a seed device, the cur_devices should point to
* its own fs_devices listed under the fs_devices->seed_list.
*/
cur_devices = device->fs_devices;
mutex_lock(&fs_devices->device_list_mutex);
list_del_rcu(&device->dev_list);
cur_devices->num_devices--;
cur_devices->total_devices--;
/* Update total_devices of the parent fs_devices if it's seed */
if (cur_devices != fs_devices)
fs_devices->total_devices--;
if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state))
cur_devices->missing_devices--;
btrfs_assign_next_active_device(device, NULL);
if (device->bdev_file) {
cur_devices->open_devices--;
/* remove sysfs entry */
btrfs_sysfs_remove_device(device);
}
num_devices = btrfs_super_num_devices(fs_info->super_copy) - 1;
btrfs_set_super_num_devices(fs_info->super_copy, num_devices);
mutex_unlock(&fs_devices->device_list_mutex);
/*
* At this point, the device is zero sized and detached from the
* devices list. All that's left is to zero out the old supers and
* free the device.
*
* We cannot call btrfs_close_bdev() here because we're holding the sb
* write lock, and fput() on the block device will pull in the
* ->open_mutex on the block device and it's dependencies. Instead
* just flush the device and let the caller do the final bdev_release.
*/
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
btrfs_scratch_superblocks(fs_info, device);
if (device->bdev) {
sync_blockdev(device->bdev);
invalidate_bdev(device->bdev);
}
}
*bdev_file = device->bdev_file;
synchronize_rcu();
btrfs_free_device(device);
/*
* This can happen if cur_devices is the private seed devices list. We
* cannot call close_fs_devices() here because it expects the uuid_mutex
* to be held, but in fact we don't need that for the private
* seed_devices, we can simply decrement cur_devices->opened and then
* remove it from our list and free the fs_devices.
*/
if (cur_devices->num_devices == 0) {
list_del_init(&cur_devices->seed_list);
ASSERT(cur_devices->opened == 1);
cur_devices->opened--;
free_fs_devices(cur_devices);
}
ret = btrfs_commit_transaction(trans);
return ret;
error_undo:
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
mutex_lock(&fs_info->chunk_mutex);
list_add(&device->dev_alloc_list,
&fs_devices->alloc_list);
device->fs_devices->rw_devices++;
mutex_unlock(&fs_info->chunk_mutex);
}
return ret;
}
void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev)
{
struct btrfs_fs_devices *fs_devices;
lockdep_assert_held(&srcdev->fs_info->fs_devices->device_list_mutex);
/*
* in case of fs with no seed, srcdev->fs_devices will point
* to fs_devices of fs_info. However when the dev being replaced is
* a seed dev it will point to the seed's local fs_devices. In short
* srcdev will have its correct fs_devices in both the cases.
*/
fs_devices = srcdev->fs_devices;
list_del_rcu(&srcdev->dev_list);
list_del(&srcdev->dev_alloc_list);
fs_devices->num_devices--;
if (test_bit(BTRFS_DEV_STATE_MISSING, &srcdev->dev_state))
fs_devices->missing_devices--;
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &srcdev->dev_state))
fs_devices->rw_devices--;
if (srcdev->bdev)
fs_devices->open_devices--;
}
void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev)
{
struct btrfs_fs_devices *fs_devices = srcdev->fs_devices;
mutex_lock(&uuid_mutex);
btrfs_close_bdev(srcdev);
synchronize_rcu();
btrfs_free_device(srcdev);
/* if this is no devs we rather delete the fs_devices */
if (!fs_devices->num_devices) {
/*
* On a mounted FS, num_devices can't be zero unless it's a
* seed. In case of a seed device being replaced, the replace
* target added to the sprout FS, so there will be no more
* device left under the seed FS.
*/
ASSERT(fs_devices->seeding);
list_del_init(&fs_devices->seed_list);
close_fs_devices(fs_devices);
free_fs_devices(fs_devices);
}
mutex_unlock(&uuid_mutex);
}
void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev)
{
struct btrfs_fs_devices *fs_devices = tgtdev->fs_info->fs_devices;
mutex_lock(&fs_devices->device_list_mutex);
btrfs_sysfs_remove_device(tgtdev);
if (tgtdev->bdev)
fs_devices->open_devices--;
fs_devices->num_devices--;
btrfs_assign_next_active_device(tgtdev, NULL);
list_del_rcu(&tgtdev->dev_list);
mutex_unlock(&fs_devices->device_list_mutex);
btrfs_scratch_superblocks(tgtdev->fs_info, tgtdev);
btrfs_close_bdev(tgtdev);
synchronize_rcu();
btrfs_free_device(tgtdev);
}
/*
* Populate args from device at path.
*
* @fs_info: the filesystem
* @args: the args to populate
* @path: the path to the device
*
* This will read the super block of the device at @path and populate @args with
* the devid, fsid, and uuid. This is meant to be used for ioctls that need to
* lookup a device to operate on, but need to do it before we take any locks.
* This properly handles the special case of "missing" that a user may pass in,
* and does some basic sanity checks. The caller must make sure that @path is
* properly NUL terminated before calling in, and must call
* btrfs_put_dev_args_from_path() in order to free up the temporary fsid and
* uuid buffers.
*
* Return: 0 for success, -errno for failure
*/
int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,
struct btrfs_dev_lookup_args *args,
const char *path)
{
struct btrfs_super_block *disk_super;
struct file *bdev_file;
int ret;
if (!path || !path[0])
return -EINVAL;
if (!strcmp(path, "missing")) {
args->missing = true;
return 0;
}
args->uuid = kzalloc(BTRFS_UUID_SIZE, GFP_KERNEL);
args->fsid = kzalloc(BTRFS_FSID_SIZE, GFP_KERNEL);
if (!args->uuid || !args->fsid) {
btrfs_put_dev_args_from_path(args);
return -ENOMEM;
}
ret = btrfs_get_bdev_and_sb(path, BLK_OPEN_READ, NULL, 0,
&bdev_file, &disk_super);
if (ret) {
btrfs_put_dev_args_from_path(args);
return ret;
}
args->devid = btrfs_stack_device_id(&disk_super->dev_item);
memcpy(args->uuid, disk_super->dev_item.uuid, BTRFS_UUID_SIZE);
if (btrfs_fs_incompat(fs_info, METADATA_UUID))
memcpy(args->fsid, disk_super->metadata_uuid, BTRFS_FSID_SIZE);
else
memcpy(args->fsid, disk_super->fsid, BTRFS_FSID_SIZE);
btrfs_release_disk_super(disk_super);
fput(bdev_file);
return 0;
}
/*
* Only use this jointly with btrfs_get_dev_args_from_path() because we will
* allocate our ->uuid and ->fsid pointers, everybody else uses local variables
* that don't need to be freed.
*/
void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args)
{
kfree(args->uuid);
kfree(args->fsid);
args->uuid = NULL;
args->fsid = NULL;
}
struct btrfs_device *btrfs_find_device_by_devspec(
struct btrfs_fs_info *fs_info, u64 devid,
const char *device_path)
{
BTRFS_DEV_LOOKUP_ARGS(args);
struct btrfs_device *device;
int ret;
if (devid) {
args.devid = devid;
device = btrfs_find_device(fs_info->fs_devices, &args);
if (!device)
return ERR_PTR(-ENOENT);
return device;
}
ret = btrfs_get_dev_args_from_path(fs_info, &args, device_path);
if (ret)
return ERR_PTR(ret);
device = btrfs_find_device(fs_info->fs_devices, &args);
btrfs_put_dev_args_from_path(&args);
if (!device)
return ERR_PTR(-ENOENT);
return device;
}
static struct btrfs_fs_devices *btrfs_init_sprout(struct btrfs_fs_info *fs_info)
{
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
struct btrfs_fs_devices *old_devices;
struct btrfs_fs_devices *seed_devices;
lockdep_assert_held(&uuid_mutex);
if (!fs_devices->seeding)
return ERR_PTR(-EINVAL);
/*
* Private copy of the seed devices, anchored at
* fs_info->fs_devices->seed_list
*/
seed_devices = alloc_fs_devices(NULL);
if (IS_ERR(seed_devices))
return seed_devices;
/*
* It's necessary to retain a copy of the original seed fs_devices in
* fs_uuids so that filesystems which have been seeded can successfully
* reference the seed device from open_seed_devices. This also supports
* multiple fs seed.
*/
old_devices = clone_fs_devices(fs_devices);
if (IS_ERR(old_devices)) {
kfree(seed_devices);
return old_devices;
}
list_add(&old_devices->fs_list, &fs_uuids);
memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
seed_devices->opened = 1;
INIT_LIST_HEAD(&seed_devices->devices);
INIT_LIST_HEAD(&seed_devices->alloc_list);
mutex_init(&seed_devices->device_list_mutex);
return seed_devices;
}
/*
* Splice seed devices into the sprout fs_devices.
* Generate a new fsid for the sprouted read-write filesystem.
*/
static void btrfs_setup_sprout(struct btrfs_fs_info *fs_info,
struct btrfs_fs_devices *seed_devices)
{
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
struct btrfs_super_block *disk_super = fs_info->super_copy;
struct btrfs_device *device;
u64 super_flags;
/*
* We are updating the fsid, the thread leading to device_list_add()
* could race, so uuid_mutex is needed.
*/
lockdep_assert_held(&uuid_mutex);
/*
* The threads listed below may traverse dev_list but can do that without
* device_list_mutex:
* - All device ops and balance - as we are in btrfs_exclop_start.
* - Various dev_list readers - are using RCU.
* - btrfs_ioctl_fitrim() - is using RCU.
*
* For-read threads as below are using device_list_mutex:
* - Readonly scrub btrfs_scrub_dev()
* - Readonly scrub btrfs_scrub_progress()
* - btrfs_get_dev_stats()
*/
lockdep_assert_held(&fs_devices->device_list_mutex);
list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices,
synchronize_rcu);
list_for_each_entry(device, &seed_devices->devices, dev_list)
device->fs_devices = seed_devices;
fs_devices->seeding = false;
fs_devices->num_devices = 0;
fs_devices->open_devices = 0;
fs_devices->missing_devices = 0;
fs_devices->rotating = false;
list_add(&seed_devices->seed_list, &fs_devices->seed_list);
generate_random_uuid(fs_devices->fsid);
memcpy(fs_devices->metadata_uuid, fs_devices->fsid, BTRFS_FSID_SIZE);
memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
super_flags = btrfs_super_flags(disk_super) &
~BTRFS_SUPER_FLAG_SEEDING;
btrfs_set_super_flags(disk_super, super_flags);
}
/*
* Store the expected generation for seed devices in device items.
*/
static int btrfs_finish_sprout(struct btrfs_trans_handle *trans)
{
BTRFS_DEV_LOOKUP_ARGS(args);
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_root *root = fs_info->chunk_root;
struct btrfs_path *path;
struct extent_buffer *leaf;
struct btrfs_dev_item *dev_item;
struct btrfs_device *device;
struct btrfs_key key;
u8 fs_uuid[BTRFS_FSID_SIZE];
u8 dev_uuid[BTRFS_UUID_SIZE];
int ret;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
key.offset = 0;
key.type = BTRFS_DEV_ITEM_KEY;
while (1) {
btrfs_reserve_chunk_metadata(trans, false);
ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
btrfs_trans_release_chunk_metadata(trans);
if (ret < 0)
goto error;
leaf = path->nodes[0];
next_slot:
if (path->slots[0] >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(root, path);
if (ret > 0)
break;
if (ret < 0)
goto error;
leaf = path->nodes[0];
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
btrfs_release_path(path);
continue;
}
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
key.type != BTRFS_DEV_ITEM_KEY)
break;
dev_item = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_dev_item);
args.devid = btrfs_device_id(leaf, dev_item);
read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
BTRFS_UUID_SIZE);
read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
BTRFS_FSID_SIZE);
args.uuid = dev_uuid;
args.fsid = fs_uuid;
device = btrfs_find_device(fs_info->fs_devices, &args);
BUG_ON(!device); /* Logic error */
if (device->fs_devices->seeding) {
btrfs_set_device_generation(leaf, dev_item,
device->generation);
btrfs_mark_buffer_dirty(trans, leaf);
}
path->slots[0]++;
goto next_slot;
}
ret = 0;
error:
btrfs_free_path(path);
return ret;
}
int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path)
{
struct btrfs_root *root = fs_info->dev_root;
struct btrfs_trans_handle *trans;
struct btrfs_device *device;
struct file *bdev_file;
struct super_block *sb = fs_info->sb;
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
struct btrfs_fs_devices *seed_devices = NULL;
u64 orig_super_total_bytes;
u64 orig_super_num_devices;
int ret = 0;
bool seeding_dev = false;
bool locked = false;
if (sb_rdonly(sb) && !fs_devices->seeding)
return -EROFS;
bdev_file = bdev_file_open_by_path(device_path, BLK_OPEN_WRITE,
fs_info->bdev_holder, NULL);
if (IS_ERR(bdev_file))
return PTR_ERR(bdev_file);
if (!btrfs_check_device_zone_type(fs_info, file_bdev(bdev_file))) {
ret = -EINVAL;
goto error;
}
if (fs_devices->seeding) {
seeding_dev = true;
down_write(&sb->s_umount);
mutex_lock(&uuid_mutex);
locked = true;
}
sync_blockdev(file_bdev(bdev_file));
rcu_read_lock();
list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
if (device->bdev == file_bdev(bdev_file)) {
ret = -EEXIST;
rcu_read_unlock();
goto error;
}
}
rcu_read_unlock();
device = btrfs_alloc_device(fs_info, NULL, NULL, device_path);
if (IS_ERR(device)) {
/* we can safely leave the fs_devices entry around */
ret = PTR_ERR(device);
goto error;
}
device->fs_info = fs_info;
device->bdev_file = bdev_file;
device->bdev = file_bdev(bdev_file);
ret = lookup_bdev(device_path, &device->devt);
if (ret)
goto error_free_device;
ret = btrfs_get_dev_zone_info(device, false);
if (ret)
goto error_free_device;
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
goto error_free_zone;
}
set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
device->generation = trans->transid;
device->io_width = fs_info->sectorsize;
device->io_align = fs_info->sectorsize;
device->sector_size = fs_info->sectorsize;
device->total_bytes =
round_down(bdev_nr_bytes(device->bdev), fs_info->sectorsize);
device->disk_total_bytes = device->total_bytes;
device->commit_total_bytes = device->total_bytes;
set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
device->dev_stats_valid = 1;
set_blocksize(device->bdev_file, BTRFS_BDEV_BLOCKSIZE);
if (seeding_dev) {
/* GFP_KERNEL allocation must not be under device_list_mutex */
seed_devices = btrfs_init_sprout(fs_info);
if (IS_ERR(seed_devices)) {
ret = PTR_ERR(seed_devices);
btrfs_abort_transaction(trans, ret);
goto error_trans;
}
}
mutex_lock(&fs_devices->device_list_mutex);
if (seeding_dev) {
btrfs_setup_sprout(fs_info, seed_devices);
btrfs_assign_next_active_device(fs_info->fs_devices->latest_dev,
device);
}
device->fs_devices = fs_devices;
mutex_lock(&fs_info->chunk_mutex);
list_add_rcu(&device->dev_list, &fs_devices->devices);
list_add(&device->dev_alloc_list, &fs_devices->alloc_list);
fs_devices->num_devices++;
fs_devices->open_devices++;
fs_devices->rw_devices++;
fs_devices->total_devices++;
fs_devices->total_rw_bytes += device->total_bytes;
atomic64_add(device->total_bytes, &fs_info->free_chunk_space);
if (!bdev_nonrot(device->bdev))
fs_devices->rotating = true;
orig_super_total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
btrfs_set_super_total_bytes(fs_info->super_copy,
round_down(orig_super_total_bytes + device->total_bytes,
fs_info->sectorsize));
orig_super_num_devices = btrfs_super_num_devices(fs_info->super_copy);
btrfs_set_super_num_devices(fs_info->super_copy,
orig_super_num_devices + 1);
/*
* we've got more storage, clear any full flags on the space
* infos
*/
btrfs_clear_space_info_full(fs_info);
mutex_unlock(&fs_info->chunk_mutex);
/* Add sysfs device entry */
btrfs_sysfs_add_device(device);
mutex_unlock(&fs_devices->device_list_mutex);
if (seeding_dev) {
mutex_lock(&fs_info->chunk_mutex);
ret = init_first_rw_device(trans);
mutex_unlock(&fs_info->chunk_mutex);
if (ret) {
btrfs_abort_transaction(trans, ret);
goto error_sysfs;
}
}
ret = btrfs_add_dev_item(trans, device);
if (ret) {
btrfs_abort_transaction(trans, ret);
goto error_sysfs;
}
if (seeding_dev) {
ret = btrfs_finish_sprout(trans);
if (ret) {
btrfs_abort_transaction(trans, ret);
goto error_sysfs;
}
/*
* fs_devices now represents the newly sprouted filesystem and
* its fsid has been changed by btrfs_sprout_splice().
*/
btrfs_sysfs_update_sprout_fsid(fs_devices);
}
ret = btrfs_commit_transaction(trans);
if (seeding_dev) {
mutex_unlock(&uuid_mutex);
up_write(&sb->s_umount);
locked = false;
if (ret) /* transaction commit */
return ret;
ret = btrfs_relocate_sys_chunks(fs_info);
if (ret < 0)
btrfs_handle_fs_error(fs_info, ret,
"Failed to relocate sys chunks after device initialization. This can be fixed using the \"btrfs balance\" command.");
trans = btrfs_attach_transaction(root);
if (IS_ERR(trans)) {
if (PTR_ERR(trans) == -ENOENT)
return 0;
ret = PTR_ERR(trans);
trans = NULL;
goto error_sysfs;
}
ret = btrfs_commit_transaction(trans);
}
/*
* Now that we have written a new super block to this device, check all
* other fs_devices list if device_path alienates any other scanned
* device.
* We can ignore the return value as it typically returns -EINVAL and
* only succeeds if the device was an alien.
*/
btrfs_forget_devices(device->devt);
/* Update ctime/mtime for blkid or udev */
update_dev_time(device_path);
return ret;
error_sysfs:
btrfs_sysfs_remove_device(device);
mutex_lock(&fs_info->fs_devices->device_list_mutex);
mutex_lock(&fs_info->chunk_mutex);
list_del_rcu(&device->dev_list);
list_del(&device->dev_alloc_list);
fs_info->fs_devices->num_devices--;
fs_info->fs_devices->open_devices--;
fs_info->fs_devices->rw_devices--;
fs_info->fs_devices->total_devices--;
fs_info->fs_devices->total_rw_bytes -= device->total_bytes;
atomic64_sub(device->total_bytes, &fs_info->free_chunk_space);
btrfs_set_super_total_bytes(fs_info->super_copy,
orig_super_total_bytes);
btrfs_set_super_num_devices(fs_info->super_copy,
orig_super_num_devices);
mutex_unlock(&fs_info->chunk_mutex);
mutex_unlock(&fs_info->fs_devices->device_list_mutex);
error_trans:
if (trans)
btrfs_end_transaction(trans);
error_free_zone:
btrfs_destroy_dev_zone_info(device);
error_free_device:
btrfs_free_device(device);
error:
fput(bdev_file);
if (locked) {
mutex_unlock(&uuid_mutex);
up_write(&sb->s_umount);
}
return ret;
}
static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
struct btrfs_device *device)
{
int ret;
struct btrfs_path *path;
struct btrfs_root *root = device->fs_info->chunk_root;
struct btrfs_dev_item *dev_item;
struct extent_buffer *leaf;
struct btrfs_key key;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
key.type = BTRFS_DEV_ITEM_KEY;
key.offset = device->devid;
ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
if (ret < 0)
goto out;
if (ret > 0) {
ret = -ENOENT;
goto out;
}
leaf = path->nodes[0];
dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
btrfs_set_device_id(leaf, dev_item, device->devid);
btrfs_set_device_type(leaf, dev_item, device->type);
btrfs_set_device_io_align(leaf, dev_item, device->io_align);
btrfs_set_device_io_width(leaf, dev_item, device->io_width);
btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
btrfs_set_device_total_bytes(leaf, dev_item,
btrfs_device_get_disk_total_bytes(device));
btrfs_set_device_bytes_used(leaf, dev_item,
btrfs_device_get_bytes_used(device));
btrfs_mark_buffer_dirty(trans, leaf);
out:
btrfs_free_path(path);
return ret;
}
int btrfs_grow_device(struct btrfs_trans_handle *trans,
struct btrfs_device *device, u64 new_size)
{
struct btrfs_fs_info *fs_info = device->fs_info;
struct btrfs_super_block *super_copy = fs_info->super_copy;
u64 old_total;
u64 diff;
int ret;
if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state))
return -EACCES;
new_size = round_down(new_size, fs_info->sectorsize);
mutex_lock(&fs_info->chunk_mutex);
old_total = btrfs_super_total_bytes(super_copy);
diff = round_down(new_size - device->total_bytes, fs_info->sectorsize);
if (new_size <= device->total_bytes ||
test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
mutex_unlock(&fs_info->chunk_mutex);
return -EINVAL;
}
btrfs_set_super_total_bytes(super_copy,
round_down(old_total + diff, fs_info->sectorsize));
device->fs_devices->total_rw_bytes += diff;
atomic64_add(diff, &fs_info->free_chunk_space);
btrfs_device_set_total_bytes(device, new_size);
btrfs_device_set_disk_total_bytes(device, new_size);
btrfs_clear_space_info_full(device->fs_info);
if (list_empty(&device->post_commit_list))
list_add_tail(&device->post_commit_list,
&trans->transaction->dev_update_list);
mutex_unlock(&fs_info->chunk_mutex);
btrfs_reserve_chunk_metadata(trans, false);
ret = btrfs_update_device(trans, device);
btrfs_trans_release_chunk_metadata(trans);
return ret;
}
static int btrfs_free_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset)
{
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_root *root = fs_info->chunk_root;
int ret;
struct btrfs_path *path;
struct btrfs_key key;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
key.offset = chunk_offset;
key.type = BTRFS_CHUNK_ITEM_KEY;
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
if (ret < 0)
goto out;
else if (ret > 0) { /* Logic error or corruption */
btrfs_err(fs_info, "failed to lookup chunk %llu when freeing",
chunk_offset);
btrfs_abort_transaction(trans, -ENOENT);
ret = -EUCLEAN;
goto out;
}
ret = btrfs_del_item(trans, root, path);
if (ret < 0) {
btrfs_err(fs_info, "failed to delete chunk %llu item", chunk_offset);
btrfs_abort_transaction(trans, ret);
goto out;
}
out:
btrfs_free_path(path);
return ret;
}
static int btrfs_del_sys_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset)
{
struct btrfs_super_block *super_copy = fs_info->super_copy;
struct btrfs_disk_key *disk_key;
struct btrfs_chunk *chunk;
u8 *ptr;
int ret = 0;
u32 num_stripes;
u32 array_size;
u32 len = 0;
u32 cur;
struct btrfs_key key;
lockdep_assert_held(&fs_info->chunk_mutex);
array_size = btrfs_super_sys_array_size(super_copy);
ptr = super_copy->sys_chunk_array;
cur = 0;
while (cur < array_size) {
disk_key = (struct btrfs_disk_key *)ptr;
btrfs_disk_key_to_cpu(&key, disk_key);
len = sizeof(*disk_key);
if (key.type == BTRFS_CHUNK_ITEM_KEY) {
chunk = (struct btrfs_chunk *)(ptr + len);
num_stripes = btrfs_stack_chunk_num_stripes(chunk);
len += btrfs_chunk_item_size(num_stripes);
} else {
ret = -EIO;
break;
}
if (key.objectid == BTRFS_FIRST_CHUNK_TREE_OBJECTID &&
key.offset == chunk_offset) {
memmove(ptr, ptr + len, array_size - (cur + len));
array_size -= len;
btrfs_set_super_sys_array_size(super_copy, array_size);
} else {
ptr += len;
cur += len;
}
}
return ret;
}
struct btrfs_chunk_map *btrfs_find_chunk_map_nolock(struct btrfs_fs_info *fs_info,
u64 logical, u64 length)
{
struct rb_node *node = fs_info->mapping_tree.rb_root.rb_node;
struct rb_node *prev = NULL;
struct rb_node *orig_prev;
struct btrfs_chunk_map *map;
struct btrfs_chunk_map *prev_map = NULL;
while (node) {
map = rb_entry(node, struct btrfs_chunk_map, rb_node);
prev = node;
prev_map = map;
if (logical < map->start) {
node = node->rb_left;
} else if (logical >= map->start + map->chunk_len) {
node = node->rb_right;
} else {
refcount_inc(&map->refs);
return map;
}
}
if (!prev)
return NULL;
orig_prev = prev;
while (prev && logical >= prev_map->start + prev_map->chunk_len) {
prev = rb_next(prev);
prev_map = rb_entry(prev, struct btrfs_chunk_map, rb_node);
}
if (!prev) {
prev = orig_prev;
prev_map = rb_entry(prev, struct btrfs_chunk_map, rb_node);
while (prev && logical < prev_map->start) {
prev = rb_prev(prev);
prev_map = rb_entry(prev, struct btrfs_chunk_map, rb_node);
}
}
if (prev) {
u64 end = logical + length;
/*
* Caller can pass a U64_MAX length when it wants to get any
* chunk starting at an offset of 'logical' or higher, so deal
* with underflow by resetting the end offset to U64_MAX.
*/
if (end < logical)
end = U64_MAX;
if (end > prev_map->start &&
logical < prev_map->start + prev_map->chunk_len) {
refcount_inc(&prev_map->refs);
return prev_map;
}
}
return NULL;
}
struct btrfs_chunk_map *btrfs_find_chunk_map(struct btrfs_fs_info *fs_info,
u64 logical, u64 length)
{
struct btrfs_chunk_map *map;
read_lock(&fs_info->mapping_tree_lock);
map = btrfs_find_chunk_map_nolock(fs_info, logical, length);
read_unlock(&fs_info->mapping_tree_lock);
return map;
}
/*
* Find the mapping containing the given logical extent.
*
* @logical: Logical block offset in bytes.
* @length: Length of extent in bytes.
*
* Return: Chunk mapping or ERR_PTR.
*/
struct btrfs_chunk_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
u64 logical, u64 length)
{
struct btrfs_chunk_map *map;
map = btrfs_find_chunk_map(fs_info, logical, length);
if (unlikely(!map)) {
btrfs_crit(fs_info,
"unable to find chunk map for logical %llu length %llu",
logical, length);
return ERR_PTR(-EINVAL);
}
if (unlikely(map->start > logical || map->start + map->chunk_len <= logical)) {
btrfs_crit(fs_info,
"found a bad chunk map, wanted %llu-%llu, found %llu-%llu",
logical, logical + length, map->start,
map->start + map->chunk_len);
btrfs_free_chunk_map(map);
return ERR_PTR(-EINVAL);
}
/* Callers are responsible for dropping the reference. */
return map;
}
static int remove_chunk_item(struct btrfs_trans_handle *trans,
struct btrfs_chunk_map *map, u64 chunk_offset)
{
int i;
/*
* Removing chunk items and updating the device items in the chunks btree
* requires holding the chunk_mutex.
* See the comment at btrfs_chunk_alloc() for the details.
*/
lockdep_assert_held(&trans->fs_info->chunk_mutex);
for (i = 0; i < map->num_stripes; i++) {
int ret;
ret = btrfs_update_device(trans, map->stripes[i].dev);
if (ret)
return ret;
}
return btrfs_free_chunk(trans, chunk_offset);
}
int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset)
{
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_chunk_map *map;
u64 dev_extent_len = 0;
int i, ret = 0;
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
map = btrfs_get_chunk_map(fs_info, chunk_offset, 1);
if (IS_ERR(map)) {
/*
* This is a logic error, but we don't want to just rely on the
* user having built with ASSERT enabled, so if ASSERT doesn't
* do anything we still error out.
*/
ASSERT(0);
return PTR_ERR(map);
}
/*
* First delete the device extent items from the devices btree.
* We take the device_list_mutex to avoid racing with the finishing phase
* of a device replace operation. See the comment below before acquiring
* fs_info->chunk_mutex. Note that here we do not acquire the chunk_mutex
* because that can result in a deadlock when deleting the device extent
* items from the devices btree - COWing an extent buffer from the btree
* may result in allocating a new metadata chunk, which would attempt to
* lock again fs_info->chunk_mutex.
*/
mutex_lock(&fs_devices->device_list_mutex);
for (i = 0; i < map->num_stripes; i++) {
struct btrfs_device *device = map->stripes[i].dev;
ret = btrfs_free_dev_extent(trans, device,
map->stripes[i].physical,
&dev_extent_len);
if (ret) {
mutex_unlock(&fs_devices->device_list_mutex);
btrfs_abort_transaction(trans, ret);
goto out;
}
if (device->bytes_used > 0) {
mutex_lock(&fs_info->chunk_mutex);
btrfs_device_set_bytes_used(device,
device->bytes_used - dev_extent_len);
atomic64_add(dev_extent_len, &fs_info->free_chunk_space);
btrfs_clear_space_info_full(fs_info);
mutex_unlock(&fs_info->chunk_mutex);
}
}
mutex_unlock(&fs_devices->device_list_mutex);
/*
* We acquire fs_info->chunk_mutex for 2 reasons:
*
* 1) Just like with the first phase of the chunk allocation, we must
* reserve system space, do all chunk btree updates and deletions, and
* update the system chunk array in the superblock while holding this
* mutex. This is for similar reasons as explained on the comment at
* the top of btrfs_chunk_alloc();
*
* 2) Prevent races with the final phase of a device replace operation
* that replaces the device object associated with the map's stripes,
* because the device object's id can change at any time during that
* final phase of the device replace operation
* (dev-replace.c:btrfs_dev_replace_finishing()), so we could grab the
* replaced device and then see it with an ID of
* BTRFS_DEV_REPLACE_DEVID, which would cause a failure when updating
* the device item, which does not exists on the chunk btree.
* The finishing phase of device replace acquires both the
* device_list_mutex and the chunk_mutex, in that order, so we are
* safe by just acquiring the chunk_mutex.
*/
trans->removing_chunk = true;
mutex_lock(&fs_info->chunk_mutex);
check_system_chunk(trans, map->type);
ret = remove_chunk_item(trans, map, chunk_offset);
/*
* Normally we should not get -ENOSPC since we reserved space before
* through the call to check_system_chunk().
*
* Despite our system space_info having enough free space, we may not
* be able to allocate extents from its block groups, because all have
* an incompatible profile, which will force us to allocate a new system
* block group with the right profile, or right after we called
* check_system_space() above, a scrub turned the only system block group
* with enough free space into RO mode.
* This is explained with more detail at do_chunk_alloc().
*
* So if we get -ENOSPC, allocate a new system chunk and retry once.
*/
if (ret == -ENOSPC) {
const u64 sys_flags = btrfs_system_alloc_profile(fs_info);
struct btrfs_block_group *sys_bg;
sys_bg = btrfs_create_chunk(trans, sys_flags);
if (IS_ERR(sys_bg)) {
ret = PTR_ERR(sys_bg);
btrfs_abort_transaction(trans, ret);
goto out;
}
ret = btrfs_chunk_alloc_add_chunk_item(trans, sys_bg);
if (ret) {
btrfs_abort_transaction(trans, ret);
goto out;
}
ret = remove_chunk_item(trans, map, chunk_offset);
if (ret) {
btrfs_abort_transaction(trans, ret);
goto out;
}
} else if (ret) {
btrfs_abort_transaction(trans, ret);
goto out;
}
trace_btrfs_chunk_free(fs_info, map, chunk_offset, map->chunk_len);
if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
ret = btrfs_del_sys_chunk(fs_info, chunk_offset);
if (ret) {
btrfs_abort_transaction(trans, ret);
goto out;
}
}
mutex_unlock(&fs_info->chunk_mutex);
trans->removing_chunk = false;
/*
* We are done with chunk btree updates and deletions, so release the
* system space we previously reserved (with check_system_chunk()).
*/
btrfs_trans_release_chunk_metadata(trans);
ret = btrfs_remove_block_group(trans, map);
if (ret) {
btrfs_abort_transaction(trans, ret);
goto out;
}
out:
if (trans->removing_chunk) {
mutex_unlock(&fs_info->chunk_mutex);
trans->removing_chunk = false;
}
/* once for us */
btrfs_free_chunk_map(map);
return ret;
}
int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset)
{
struct btrfs_root *root = fs_info->chunk_root;
struct btrfs_trans_handle *trans;
struct btrfs_block_group *block_group;
u64 length;
int ret;
if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
btrfs_err(fs_info,
"relocate: not supported on extent tree v2 yet");
return -EINVAL;
}
/*
* Prevent races with automatic removal of unused block groups.
* After we relocate and before we remove the chunk with offset
* chunk_offset, automatic removal of the block group can kick in,
* resulting in a failure when calling btrfs_remove_chunk() below.
*
* Make sure to acquire this mutex before doing a tree search (dev
* or chunk trees) to find chunks. Otherwise the cleaner kthread might
* call btrfs_remove_chunk() (through btrfs_delete_unused_bgs()) after
* we release the path used to search the chunk/dev tree and before
* the current task acquires this mutex and calls us.
*/
lockdep_assert_held(&fs_info->reclaim_bgs_lock);
/* step one, relocate all the extents inside this chunk */
btrfs_scrub_pause(fs_info);
ret = btrfs_relocate_block_group(fs_info, chunk_offset);
btrfs_scrub_continue(fs_info);
if (ret) {
/*
* If we had a transaction abort, stop all running scrubs.
* See transaction.c:cleanup_transaction() why we do it here.
*/
if (BTRFS_FS_ERROR(fs_info))
btrfs_scrub_cancel(fs_info);
return ret;
}
block_group = btrfs_lookup_block_group(fs_info, chunk_offset);
if (!block_group)
return -ENOENT;
btrfs_discard_cancel_work(&fs_info->discard_ctl, block_group);
length = block_group->length;
btrfs_put_block_group(block_group);
/*
* On a zoned file system, discard the whole block group, this will
* trigger a REQ_OP_ZONE_RESET operation on the device zone. If
* resetting the zone fails, don't treat it as a fatal problem from the
* filesystem's point of view.
*/
if (btrfs_is_zoned(fs_info)) {
ret = btrfs_discard_extent(fs_info, chunk_offset, length, NULL);
if (ret)
btrfs_info(fs_info,
"failed to reset zone %llu after relocation",
chunk_offset);
}
trans = btrfs_start_trans_remove_block_group(root->fs_info,
chunk_offset);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
btrfs_handle_fs_error(root->fs_info, ret, NULL);
return ret;
}
/*
* step two, delete the device extents and the
* chunk tree entries
*/
ret = btrfs_remove_chunk(trans, chunk_offset);
btrfs_end_transaction(trans);
return ret;
}
static int btrfs_relocate_sys_chunks(struct btrfs_fs_info *fs_info)
{
struct btrfs_root *chunk_root = fs_info->chunk_root;
struct btrfs_path *path;
struct extent_buffer *leaf;
struct btrfs_chunk *chunk;
struct btrfs_key key;
struct btrfs_key found_key;
u64 chunk_type;
bool retried = false;
int failed = 0;
int ret;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
again:
key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
key.offset = (u64)-1;
key.type = BTRFS_CHUNK_ITEM_KEY;
while (1) {
mutex_lock(&fs_info->reclaim_bgs_lock);
ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
if (ret < 0) {
mutex_unlock(&fs_info->reclaim_bgs_lock);
goto error;
}
if (ret == 0) {
/*
* On the first search we would find chunk tree with
* offset -1, which is not possible. On subsequent
* loops this would find an existing item on an invalid
* offset (one less than the previous one, wrong
* alignment and size).
*/
ret = -EUCLEAN;
mutex_unlock(&fs_info->reclaim_bgs_lock);
goto error;
}
ret = btrfs_previous_item(chunk_root, path, key.objectid,
key.type);
if (ret)
mutex_unlock(&fs_info->reclaim_bgs_lock);
if (ret < 0)
goto error;
if (ret > 0)
break;
leaf = path->nodes[0];
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
chunk = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_chunk);
chunk_type = btrfs_chunk_type(leaf, chunk);
btrfs_release_path(path);
if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
ret = btrfs_relocate_chunk(fs_info, found_key.offset);
if (ret == -ENOSPC)
failed++;
else
BUG_ON(ret);
}
mutex_unlock(&fs_info->reclaim_bgs_lock);
if (found_key.offset == 0)
break;
key.offset = found_key.offset - 1;
}
ret = 0;
if (failed && !retried) {
failed = 0;
retried = true;
goto again;
} else if (WARN_ON(failed && retried)) {
ret = -ENOSPC;
}
error:
btrfs_free_path(path);
return ret;
}
/*
* return 1 : allocate a data chunk successfully,
* return <0: errors during allocating a data chunk,
* return 0 : no need to allocate a data chunk.
*/
static int btrfs_may_alloc_data_chunk(struct btrfs_fs_info *fs_info,
u64 chunk_offset)
{
struct btrfs_block_group *cache;
u64 bytes_used;
u64 chunk_type;
cache = btrfs_lookup_block_group(fs_info, chunk_offset);
ASSERT(cache);
chunk_type = cache->flags;
btrfs_put_block_group(cache);
if (!(chunk_type & BTRFS_BLOCK_GROUP_DATA))
return 0;
spin_lock(&fs_info->data_sinfo->lock);
bytes_used = fs_info->data_sinfo->bytes_used;
spin_unlock(&fs_info->data_sinfo->lock);
if (!bytes_used) {
struct btrfs_trans_handle *trans;
int ret;
trans = btrfs_join_transaction(fs_info->tree_root);
if (IS_ERR(trans))
return PTR_ERR(trans);
ret = btrfs_force_chunk_alloc(trans, BTRFS_BLOCK_GROUP_DATA);
btrfs_end_transaction(trans);
if (ret < 0)
return ret;
return 1;
}
return 0;
}
static void btrfs_disk_balance_args_to_cpu(struct btrfs_balance_args *cpu,
const struct btrfs_disk_balance_args *disk)
{
memset(cpu, 0, sizeof(*cpu));
cpu->profiles = le64_to_cpu(disk->profiles);
cpu->usage = le64_to_cpu(disk->usage);
cpu->devid = le64_to_cpu(disk->devid);
cpu->pstart = le64_to_cpu(disk->pstart);
cpu->pend = le64_to_cpu(disk->pend);
cpu->vstart = le64_to_cpu(disk->vstart);
cpu->vend = le64_to_cpu(disk->vend);
cpu->target = le64_to_cpu(disk->target);
cpu->flags = le64_to_cpu(disk->flags);
cpu->limit = le64_to_cpu(disk->limit);
cpu->stripes_min = le32_to_cpu(disk->stripes_min);
cpu->stripes_max = le32_to_cpu(disk->stripes_max);
}
static void btrfs_cpu_balance_args_to_disk(struct btrfs_disk_balance_args *disk,
const struct btrfs_balance_args *cpu)
{
memset(disk, 0, sizeof(*disk));
disk->profiles = cpu_to_le64(cpu->profiles);
disk->usage = cpu_to_le64(cpu->usage);
disk->devid = cpu_to_le64(cpu->devid);
disk->pstart = cpu_to_le64(cpu->pstart);
disk->pend = cpu_to_le64(cpu->pend);
disk->vstart = cpu_to_le64(cpu->vstart);
disk->vend = cpu_to_le64(cpu->vend);
disk->target = cpu_to_le64(cpu->target);
disk->flags = cpu_to_le64(cpu->flags);
disk->limit = cpu_to_le64(cpu->limit);
disk->stripes_min = cpu_to_le32(cpu->stripes_min);
disk->stripes_max = cpu_to_le32(cpu->stripes_max);
}
static int insert_balance_item(struct btrfs_fs_info *fs_info,
struct btrfs_balance_control *bctl)
{
struct btrfs_root *root = fs_info->tree_root;
struct btrfs_trans_handle *trans;
struct btrfs_balance_item *item;
struct btrfs_disk_balance_args disk_bargs;
struct btrfs_path *path;
struct extent_buffer *leaf;
struct btrfs_key key;
int ret, err;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
btrfs_free_path(path);
return PTR_ERR(trans);
}
key.objectid = BTRFS_BALANCE_OBJECTID;
key.type = BTRFS_TEMPORARY_ITEM_KEY;
key.offset = 0;
ret = btrfs_insert_empty_item(trans, root, path, &key,
sizeof(*item));
if (ret)
goto out;
leaf = path->nodes[0];
item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
memzero_extent_buffer(leaf, (unsigned long)item, sizeof(*item));
btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data);
btrfs_set_balance_data(leaf, item, &disk_bargs);
btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta);
btrfs_set_balance_meta(leaf, item, &disk_bargs);
btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys);
btrfs_set_balance_sys(leaf, item, &disk_bargs);
btrfs_set_balance_flags(leaf, item, bctl->flags);
btrfs_mark_buffer_dirty(trans, leaf);
out:
btrfs_free_path(path);
err = btrfs_commit_transaction(trans);
if (err && !ret)
ret = err;
return ret;
}
static int del_balance_item(struct btrfs_fs_info *fs_info)
{
struct btrfs_root *root = fs_info->tree_root;
struct btrfs_trans_handle *trans;
struct btrfs_path *path;
struct btrfs_key key;
int ret, err;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
trans = btrfs_start_transaction_fallback_global_rsv(root, 0);
if (IS_ERR(trans)) {
btrfs_free_path(path);
return PTR_ERR(trans);
}
key.objectid = BTRFS_BALANCE_OBJECTID;
key.type = BTRFS_TEMPORARY_ITEM_KEY;
key.offset = 0;
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
if (ret < 0)
goto out;
if (ret > 0) {
ret = -ENOENT;
goto out;
}
ret = btrfs_del_item(trans, root, path);
out:
btrfs_free_path(path);
err = btrfs_commit_transaction(trans);
if (err && !ret)
ret = err;
return ret;
}
/*
* This is a heuristic used to reduce the number of chunks balanced on
* resume after balance was interrupted.
*/
static void update_balance_args(struct btrfs_balance_control *bctl)
{
/*
* Turn on soft mode for chunk types that were being converted.
*/
if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)
bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT;
if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)
bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT;
if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)
bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT;
/*
* Turn on usage filter if is not already used. The idea is
* that chunks that we have already balanced should be
* reasonably full. Don't do it for chunks that are being
* converted - that will keep us from relocating unconverted
* (albeit full) chunks.
*/
if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) &&
!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
!(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE;
bctl->data.usage = 90;
}
if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) &&
!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
!(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE;
bctl->sys.usage = 90;
}
if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) &&
!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
!(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE;
bctl->meta.usage = 90;
}
}
/*
* Clear the balance status in fs_info and delete the balance item from disk.
*/
static void reset_balance_state(struct btrfs_fs_info *fs_info)
{
struct btrfs_balance_control *bctl = fs_info->balance_ctl;
int ret;
ASSERT(fs_info->balance_ctl);
spin_lock(&fs_info->balance_lock);
fs_info->balance_ctl = NULL;
spin_unlock(&fs_info->balance_lock);
kfree(bctl);
ret = del_balance_item(fs_info);
if (ret)
btrfs_handle_fs_error(fs_info, ret, NULL);
}
/*
* Balance filters. Return 1 if chunk should be filtered out
* (should not be balanced).
*/
static int chunk_profiles_filter(u64 chunk_type,
struct btrfs_balance_args *bargs)
{
chunk_type = chunk_to_extended(chunk_type) &
BTRFS_EXTENDED_PROFILE_MASK;
if (bargs->profiles & chunk_type)
return 0;
return 1;
}
static int chunk_usage_range_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset,
struct btrfs_balance_args *bargs)
{
struct btrfs_block_group *cache;
u64 chunk_used;
u64 user_thresh_min;
u64 user_thresh_max;
int ret = 1;
cache = btrfs_lookup_block_group(fs_info, chunk_offset);
chunk_used = cache->used;
if (bargs->usage_min == 0)
user_thresh_min = 0;
else
user_thresh_min = mult_perc(cache->length, bargs->usage_min);
if (bargs->usage_max == 0)
user_thresh_max = 1;
else if (bargs->usage_max > 100)
user_thresh_max = cache->length;
else
user_thresh_max = mult_perc(cache->length, bargs->usage_max);
if (user_thresh_min <= chunk_used && chunk_used < user_thresh_max)
ret = 0;
btrfs_put_block_group(cache);
return ret;
}
static int chunk_usage_filter(struct btrfs_fs_info *fs_info,
u64 chunk_offset, struct btrfs_balance_args *bargs)
{
struct btrfs_block_group *cache;
u64 chunk_used, user_thresh;
int ret = 1;
cache = btrfs_lookup_block_group(fs_info, chunk_offset);
chunk_used = cache->used;
if (bargs->usage_min == 0)
user_thresh = 1;
else if (bargs->usage > 100)
user_thresh = cache->length;
else
user_thresh = mult_perc(cache->length, bargs->usage);
if (chunk_used < user_thresh)
ret = 0;
btrfs_put_block_group(cache);
return ret;
}
static int chunk_devid_filter(struct extent_buffer *leaf,
struct btrfs_chunk *chunk,
struct btrfs_balance_args *bargs)
{
struct btrfs_stripe *stripe;
int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
int i;
for (i = 0; i < num_stripes; i++) {
stripe = btrfs_stripe_nr(chunk, i);
if (btrfs_stripe_devid(leaf, stripe) == bargs->devid)
return 0;
}
return 1;
}
static u64 calc_data_stripes(u64 type, int num_stripes)
{
const int index = btrfs_bg_flags_to_raid_index(type);
const int ncopies = btrfs_raid_array[index].ncopies;
const int nparity = btrfs_raid_array[index].nparity;
return (num_stripes - nparity) / ncopies;
}
/* [pstart, pend) */
static int chunk_drange_filter(struct extent_buffer *leaf,
struct btrfs_chunk *chunk,
struct btrfs_balance_args *bargs)
{
struct btrfs_stripe *stripe;
int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
u64 stripe_offset;
u64 stripe_length;
u64 type;
int factor;
int i;
if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID))
return 0;
type = btrfs_chunk_type(leaf, chunk);
factor = calc_data_stripes(type, num_stripes);
for (i = 0; i < num_stripes; i++) {
stripe = btrfs_stripe_nr(chunk, i);
if (btrfs_stripe_devid(leaf, stripe) != bargs->devid)
continue;
stripe_offset = btrfs_stripe_offset(leaf, stripe);
stripe_length = btrfs_chunk_length(leaf, chunk);
stripe_length = div_u64(stripe_length, factor);
if (stripe_offset < bargs->pend &&
stripe_offset + stripe_length > bargs->pstart)
return 0;
}
return 1;
}
/* [vstart, vend) */
static int chunk_vrange_filter(struct extent_buffer *leaf,
struct btrfs_chunk *chunk,
u64 chunk_offset,
struct btrfs_balance_args *bargs)
{
if (chunk_offset < bargs->vend &&
chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart)
/* at least part of the chunk is inside this vrange */
return 0;
return 1;
}
static int chunk_stripes_range_filter(struct extent_buffer *leaf,
struct btrfs_chunk *chunk,
struct btrfs_balance_args *bargs)
{
int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
if (bargs->stripes_min <= num_stripes
&& num_stripes <= bargs->stripes_max)
return 0;
return 1;
}
static int chunk_soft_convert_filter(u64 chunk_type,
struct btrfs_balance_args *bargs)
{
if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
return 0;
chunk_type = chunk_to_extended(chunk_type) &
BTRFS_EXTENDED_PROFILE_MASK;
if (bargs->target == chunk_type)
return 1;
return 0;
}
static int should_balance_chunk(struct extent_buffer *leaf,
struct btrfs_chunk *chunk, u64 chunk_offset)
{
struct btrfs_fs_info *fs_info = leaf->fs_info;
struct btrfs_balance_control *bctl = fs_info->balance_ctl;
struct btrfs_balance_args *bargs = NULL;
u64 chunk_type = btrfs_chunk_type(leaf, chunk);
/* type filter */
if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) &
(bctl->flags & BTRFS_BALANCE_TYPE_MASK))) {
return 0;
}
if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
bargs = &bctl->data;
else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
bargs = &bctl->sys;
else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
bargs = &bctl->meta;
/* profiles filter */
if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) &&
chunk_profiles_filter(chunk_type, bargs)) {
return 0;
}
/* usage filter */
if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) &&
chunk_usage_filter(fs_info, chunk_offset, bargs)) {
return 0;
} else if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
chunk_usage_range_filter(fs_info, chunk_offset, bargs)) {
return 0;
}
/* devid filter */
if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) &&
chunk_devid_filter(leaf, chunk, bargs)) {
return 0;
}
/* drange filter, makes sense only with devid filter */
if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) &&
chunk_drange_filter(leaf, chunk, bargs)) {
return 0;
}
/* vrange filter */
if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) &&
chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) {
return 0;
}
/* stripes filter */
if ((bargs->flags & BTRFS_BALANCE_ARGS_STRIPES_RANGE) &&
chunk_stripes_range_filter(leaf, chunk, bargs)) {
return 0;
}
/* soft profile changing mode */
if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) &&
chunk_soft_convert_filter(chunk_type, bargs)) {
return 0;
}
/*
* limited by count, must be the last filter
*/
if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT)) {
if (bargs->limit == 0)
return 0;
else
bargs->limit--;
} else if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT_RANGE)) {
/*
* Same logic as the 'limit' filter; the minimum cannot be
* determined here because we do not have the global information
* about the count of all chunks that satisfy the filters.
*/
if (bargs->limit_max == 0)
return 0;
else
bargs->limit_max--;
}
return 1;
}
static int __btrfs_balance(struct btrfs_fs_info *fs_info)
{
struct btrfs_balance_control *bctl = fs_info->balance_ctl;
struct btrfs_root *chunk_root = fs_info->chunk_root;
u64 chunk_type;
struct btrfs_chunk *chunk;
struct btrfs_path *path = NULL;
struct btrfs_key key;
struct btrfs_key found_key;
struct extent_buffer *leaf;
int slot;
int ret;
int enospc_errors = 0;
bool counting = true;
/* The single value limit and min/max limits use the same bytes in the */
u64 limit_data = bctl->data.limit;
u64 limit_meta = bctl->meta.limit;
u64 limit_sys = bctl->sys.limit;
u32 count_data = 0;
u32 count_meta = 0;
u32 count_sys = 0;
int chunk_reserved = 0;
path = btrfs_alloc_path();
if (!path) {
ret = -ENOMEM;
goto error;
}
/* zero out stat counters */
spin_lock(&fs_info->balance_lock);
memset(&bctl->stat, 0, sizeof(bctl->stat));
spin_unlock(&fs_info->balance_lock);
again:
if (!counting) {
/*
* The single value limit and min/max limits use the same bytes
* in the
*/
bctl->data.limit = limit_data;
bctl->meta.limit = limit_meta;
bctl->sys.limit = limit_sys;
}
key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
key.offset = (u64)-1;
key.type = BTRFS_CHUNK_ITEM_KEY;
while (1) {
if ((!counting && atomic_read(&fs_info->balance_pause_req)) ||
atomic_read(&fs_info->balance_cancel_req)) {
ret = -ECANCELED;
goto error;
}
mutex_lock(&fs_info->reclaim_bgs_lock);
ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
if (ret < 0) {
mutex_unlock(&fs_info->reclaim_bgs_lock);
goto error;
}
/*
* this shouldn't happen, it means the last relocate
* failed
*/
if (ret == 0)
BUG(); /* FIXME break ? */
ret = btrfs_previous_item(chunk_root, path, 0,
BTRFS_CHUNK_ITEM_KEY);
if (ret) {
mutex_unlock(&fs_info->reclaim_bgs_lock);
ret = 0;
break;
}
leaf = path->nodes[0];
slot = path->slots[0];
btrfs_item_key_to_cpu(leaf, &found_key, slot);
if (found_key.objectid != key.objectid) {
mutex_unlock(&fs_info->reclaim_bgs_lock);
break;
}
chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
chunk_type = btrfs_chunk_type(leaf, chunk);
if (!counting) {
spin_lock(&fs_info->balance_lock);
bctl->stat.considered++;
spin_unlock(&fs_info->balance_lock);
}
ret = should_balance_chunk(leaf, chunk, found_key.offset);
btrfs_release_path(path);
if (!ret) {
mutex_unlock(&fs_info->reclaim_bgs_lock);
goto loop;
}
if (counting) {
mutex_unlock(&fs_info->reclaim_bgs_lock);
spin_lock(&fs_info->balance_lock);
bctl->stat.expected++;
spin_unlock(&fs_info->balance_lock);
if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
count_data++;
else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
count_sys++;
else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
count_meta++;
goto loop;
}
/*
* Apply limit_min filter, no need to check if the LIMITS
* filter is used, limit_min is 0 by default
*/
if (((chunk_type & BTRFS_BLOCK_GROUP_DATA) &&
count_data < bctl->data.limit_min)
|| ((chunk_type & BTRFS_BLOCK_GROUP_METADATA) &&
count_meta < bctl->meta.limit_min)
|| ((chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) &&
count_sys < bctl->sys.limit_min)) {
mutex_unlock(&fs_info->reclaim_bgs_lock);
goto loop;
}
if (!chunk_reserved) {
/*
* We may be relocating the only data chunk we have,
* which could potentially end up with losing data's
* raid profile, so lets allocate an empty one in
* advance.
*/
ret = btrfs_may_alloc_data_chunk(fs_info,
found_key.offset);
if (ret < 0) {
mutex_unlock(&fs_info->reclaim_bgs_lock);
goto error;
} else if (ret == 1) {
chunk_reserved = 1;
}
}
ret = btrfs_relocate_chunk(fs_info, found_key.offset);
mutex_unlock(&fs_info->reclaim_bgs_lock);
if (ret == -ENOSPC) {
enospc_errors++;
} else if (ret == -ETXTBSY) {
btrfs_info(fs_info,
"skipping relocation of block group %llu due to active swapfile",
found_key.offset);
ret = 0;
} else if (ret) {
goto error;
} else {
spin_lock(&fs_info->balance_lock);
bctl->stat.completed++;
spin_unlock(&fs_info->balance_lock);
}
loop:
if (found_key.offset == 0)
break;
key.offset = found_key.offset - 1;
}
if (counting) {
btrfs_release_path(path);
counting = false;
goto again;
}
error:
btrfs_free_path(path);
if (enospc_errors) {
btrfs_info(fs_info, "%d enospc errors during balance",
enospc_errors);
if (!ret)
ret = -ENOSPC;
}
return ret;
}
/*
* See if a given profile is valid and reduced.
*
* @flags: profile to validate
* @extended: if true @flags is treated as an extended profile
*/
static int alloc_profile_is_valid(u64 flags, int extended)
{
u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK :
BTRFS_BLOCK_GROUP_PROFILE_MASK);
flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK;
/* 1) check that all other bits are zeroed */
if (flags & ~mask)
return 0;
/* 2) see if profile is reduced */
if (flags == 0)
return !extended; /* "0" is valid for usual profiles */
return has_single_bit_set(flags);
}
/*
* Validate target profile against allowed profiles and return true if it's OK.
* Otherwise print the error message and return false.
*/
static inline int validate_convert_profile(struct btrfs_fs_info *fs_info,
const struct btrfs_balance_args *bargs,
u64 allowed, const char *type)
{
if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
return true;
/* Profile is valid and does not have bits outside of the allowed set */
if (alloc_profile_is_valid(bargs->target, 1) &&
(bargs->target & ~allowed) == 0)
return true;
btrfs_err(fs_info, "balance: invalid convert %s profile %s",
type, btrfs_bg_type_to_raid_name(bargs->target));
return false;
}
/*
* Fill @buf with textual description of balance filter flags @bargs, up to
* @size_buf including the terminating null. The output may be trimmed if it
* does not fit into the provided buffer.
*/
static void describe_balance_args(struct btrfs_balance_args *bargs, char *buf,
u32 size_buf)
{
int ret;
u32 size_bp = size_buf;
char *bp = buf;
u64 flags = bargs->flags;
char tmp_buf[128] = {'\0'};
if (!flags)
return;
#define CHECK_APPEND_NOARG(a) \
do { \
ret = snprintf(bp, size_bp, (a)); \
if (ret < 0 || ret >= size_bp) \
goto out_overflow; \
size_bp -= ret; \
bp += ret; \
} while (0)
#define CHECK_APPEND_1ARG(a, v1) \
do { \
ret = snprintf(bp, size_bp, (a), (v1)); \
if (ret < 0 || ret >= size_bp) \
goto out_overflow; \
size_bp -= ret; \
bp += ret; \
} while (0)
#define CHECK_APPEND_2ARG(a, v1, v2) \
do { \
ret = snprintf(bp, size_bp, (a), (v1), (v2)); \
if (ret < 0 || ret >= size_bp) \
goto out_overflow; \
size_bp -= ret; \
bp += ret; \
} while (0)
if (flags & BTRFS_BALANCE_ARGS_CONVERT)
CHECK_APPEND_1ARG("convert=%s,",
btrfs_bg_type_to_raid_name(bargs->target));
if (flags & BTRFS_BALANCE_ARGS_SOFT)
CHECK_APPEND_NOARG("soft,");
if (flags & BTRFS_BALANCE_ARGS_PROFILES) {
btrfs_describe_block_groups(bargs->profiles, tmp_buf,
sizeof(tmp_buf));
CHECK_APPEND_1ARG("profiles=%s,", tmp_buf);
}
if (flags & BTRFS_BALANCE_ARGS_USAGE)
CHECK_APPEND_1ARG("usage=%llu,", bargs->usage);
if (flags & BTRFS_BALANCE_ARGS_USAGE_RANGE)
CHECK_APPEND_2ARG("usage=%u..%u,",
bargs->usage_min, bargs->usage_max);
if (flags & BTRFS_BALANCE_ARGS_DEVID)
CHECK_APPEND_1ARG("devid=%llu,", bargs->devid);
if (flags & BTRFS_BALANCE_ARGS_DRANGE)
CHECK_APPEND_2ARG("drange=%llu..%llu,",
bargs->pstart, bargs->pend);
if (flags & BTRFS_BALANCE_ARGS_VRANGE)
CHECK_APPEND_2ARG("vrange=%llu..%llu,",
bargs->vstart, bargs->vend);
if (flags & BTRFS_BALANCE_ARGS_LIMIT)
CHECK_APPEND_1ARG("limit=%llu,", bargs->limit);
if (flags & BTRFS_BALANCE_ARGS_LIMIT_RANGE)
CHECK_APPEND_2ARG("limit=%u..%u,",
bargs->limit_min, bargs->limit_max);
if (flags & BTRFS_BALANCE_ARGS_STRIPES_RANGE)
CHECK_APPEND_2ARG("stripes=%u..%u,",
bargs->stripes_min, bargs->stripes_max);
#undef CHECK_APPEND_2ARG
#undef CHECK_APPEND_1ARG
#undef CHECK_APPEND_NOARG
out_overflow:
if (size_bp < size_buf)
buf[size_buf - size_bp - 1] = '\0'; /* remove last , */
else
buf[0] = '\0';
}
static void describe_balance_start_or_resume(struct btrfs_fs_info *fs_info)
{
u32 size_buf = 1024;
char tmp_buf[192] = {'\0'};
char *buf;
char *bp;
u32 size_bp = size_buf;
int ret;
struct btrfs_balance_control *bctl = fs_info->balance_ctl;
buf = kzalloc(size_buf, GFP_KERNEL);
if (!buf)
return;
bp = buf;
#define CHECK_APPEND_1ARG(a, v1) \
do { \
ret = snprintf(bp, size_bp, (a), (v1)); \
if (ret < 0 || ret >= size_bp) \
goto out_overflow; \
size_bp -= ret; \
bp += ret; \
} while (0)
if (bctl->flags & BTRFS_BALANCE_FORCE)
CHECK_APPEND_1ARG("%s", "-f ");
if (bctl->flags & BTRFS_BALANCE_DATA) {
describe_balance_args(&bctl->data, tmp_buf, sizeof(tmp_buf));
CHECK_APPEND_1ARG("-d%s ", tmp_buf);
}
if (bctl->flags & BTRFS_BALANCE_METADATA) {
describe_balance_args(&bctl->meta, tmp_buf, sizeof(tmp_buf));
CHECK_APPEND_1ARG("-m%s ", tmp_buf);
}
if (bctl->flags & BTRFS_BALANCE_SYSTEM) {
describe_balance_args(&bctl->sys, tmp_buf, sizeof(tmp_buf));
CHECK_APPEND_1ARG("-s%s ", tmp_buf);
}
#undef CHECK_APPEND_1ARG
out_overflow:
if (size_bp < size_buf)
buf[size_buf - size_bp - 1] = '\0'; /* remove last " " */
btrfs_info(fs_info, "balance: %s %s",
(bctl->flags & BTRFS_BALANCE_RESUME) ?
"resume" : "start", buf);
kfree(buf);
}
/*
* Should be called with balance mutexe held
*/
int btrfs_balance(struct btrfs_fs_info *fs_info,
struct btrfs_balance_control *bctl,
struct btrfs_ioctl_balance_args *bargs)
{
u64 meta_target, data_target;
u64 allowed;
int mixed = 0;
int ret;
u64 num_devices;
unsigned seq;
bool reducing_redundancy;
bool paused = false;
int i;
if (btrfs_fs_closing(fs_info) ||
atomic_read(&fs_info->balance_pause_req) ||
btrfs_should_cancel_balance(fs_info)) {
ret = -EINVAL;
goto out;
}
allowed = btrfs_super_incompat_flags(fs_info->super_copy);
if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
mixed = 1;
/*
* In case of mixed groups both data and meta should be picked,
* and identical options should be given for both of them.
*/
allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA;
if (mixed && (bctl->flags & allowed)) {
if (!(bctl->flags & BTRFS_BALANCE_DATA) ||
!(bctl->flags & BTRFS_BALANCE_METADATA) ||
memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) {
btrfs_err(fs_info,
"balance: mixed groups data and metadata options must be the same");
ret = -EINVAL;
goto out;
}
}
/*
* rw_devices will not change at the moment, device add/delete/replace
* are exclusive
*/
num_devices = fs_info->fs_devices->rw_devices;
/*
* SINGLE profile on-disk has no profile bit, but in-memory we have a
* special bit for it, to make it easier to distinguish. Thus we need
* to set it manually, or balance would refuse the profile.
*/
allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
for (i = 0; i < ARRAY_SIZE(btrfs_raid_array); i++)
if (num_devices >= btrfs_raid_array[i].devs_min)
allowed |= btrfs_raid_array[i].bg_flag;
if (!validate_convert_profile(fs_info, &bctl->data, allowed, "data") ||
!validate_convert_profile(fs_info, &bctl->meta, allowed, "metadata") ||
!validate_convert_profile(fs_info, &bctl->sys, allowed, "system")) {
ret = -EINVAL;
goto out;
}
/*
* Allow to reduce metadata or system integrity only if force set for
* profiles with redundancy (copies, parity)
*/
allowed = 0;
for (i = 0; i < ARRAY_SIZE(btrfs_raid_array); i++) {
if (btrfs_raid_array[i].ncopies >= 2 ||
btrfs_raid_array[i].tolerated_failures >= 1)
allowed |= btrfs_raid_array[i].bg_flag;
}
do {
seq = read_seqbegin(&fs_info->profiles_lock);
if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
(fs_info->avail_system_alloc_bits & allowed) &&
!(bctl->sys.target & allowed)) ||
((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
(fs_info->avail_metadata_alloc_bits & allowed) &&
!(bctl->meta.target & allowed)))
reducing_redundancy = true;
else
reducing_redundancy = false;
/* if we're not converting, the target field is uninitialized */
meta_target = (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) ?
bctl->meta.target : fs_info->avail_metadata_alloc_bits;
data_target = (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) ?
bctl->data.target : fs_info->avail_data_alloc_bits;
} while (read_seqretry(&fs_info->profiles_lock, seq));
if (reducing_redundancy) {
if (bctl->flags & BTRFS_BALANCE_FORCE) {
btrfs_info(fs_info,
"balance: force reducing metadata redundancy");
} else {
btrfs_err(fs_info,
"balance: reduces metadata redundancy, use --force if you want this");
ret = -EINVAL;
goto out;
}
}
if (btrfs_get_num_tolerated_disk_barrier_failures(meta_target) <
btrfs_get_num_tolerated_disk_barrier_failures(data_target)) {
btrfs_warn(fs_info,
"balance: metadata profile %s has lower redundancy than data profile %s",
btrfs_bg_type_to_raid_name(meta_target),
btrfs_bg_type_to_raid_name(data_target));
}
ret = insert_balance_item(fs_info, bctl);
if (ret && ret != -EEXIST)
goto out;
if (!(bctl->flags & BTRFS_BALANCE_RESUME)) {
BUG_ON(ret == -EEXIST);
BUG_ON(fs_info->balance_ctl);
spin_lock(&fs_info->balance_lock);
fs_info->balance_ctl = bctl;
spin_unlock(&fs_info->balance_lock);
} else {
BUG_ON(ret != -EEXIST);
spin_lock(&fs_info->balance_lock);
update_balance_args(bctl);
spin_unlock(&fs_info->balance_lock);
}
ASSERT(!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
set_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags);
describe_balance_start_or_resume(fs_info);
mutex_unlock(&fs_info->balance_mutex);
ret = __btrfs_balance(fs_info);
mutex_lock(&fs_info->balance_mutex);
if (ret == -ECANCELED && atomic_read(&fs_info->balance_pause_req)) {
btrfs_info(fs_info, "balance: paused");
btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED);
paused = true;
}
/*
* Balance can be canceled by:
*
* - Regular cancel request
* Then ret == -ECANCELED and balance_cancel_req > 0
*
* - Fatal signal to "btrfs" process
* Either the signal caught by wait_reserve_ticket() and callers
* got -EINTR, or caught by btrfs_should_cancel_balance() and
* got -ECANCELED.
* Either way, in this case balance_cancel_req = 0, and
* ret == -EINTR or ret == -ECANCELED.
*
* So here we only check the return value to catch canceled balance.
*/
else if (ret == -ECANCELED || ret == -EINTR)
btrfs_info(fs_info, "balance: canceled");
else
btrfs_info(fs_info, "balance: ended with status: %d", ret);
clear_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags);
if (bargs) {
memset(bargs, 0, sizeof(*bargs));
btrfs_update_ioctl_balance_args(fs_info, bargs);
}
/* We didn't pause, we can clean everything up. */
if (!paused) {
reset_balance_state(fs_info);
btrfs_exclop_finish(fs_info);
}
wake_up(&fs_info->balance_wait_q);
return ret;
out:
if (bctl->flags & BTRFS_BALANCE_RESUME)
reset_balance_state(fs_info);
else
kfree(bctl);
btrfs_exclop_finish(fs_info);
return ret;
}
static int balance_kthread(void *data)
{
struct btrfs_fs_info *fs_info = data;
int ret = 0;
sb_start_write(fs_info->sb);
mutex_lock(&fs_info->balance_mutex);
if (fs_info->balance_ctl)
ret = btrfs_balance(fs_info, fs_info->balance_ctl, NULL);
mutex_unlock(&fs_info->balance_mutex);
sb_end_write(fs_info->sb);
return ret;
}
int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info)
{
struct task_struct *tsk;
mutex_lock(&fs_info->balance_mutex);
if (!fs_info->balance_ctl) {
mutex_unlock(&fs_info->balance_mutex);
return 0;
}
mutex_unlock(&fs_info->balance_mutex);
if (btrfs_test_opt(fs_info, SKIP_BALANCE)) {
btrfs_info(fs_info, "balance: resume skipped");
return 0;
}
spin_lock(&fs_info->super_lock);
ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED);
fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE;
spin_unlock(&fs_info->super_lock);
/*
* A ro->rw remount sequence should continue with the paused balance
* regardless of who pauses it, system or the user as of now, so set
* the resume flag.
*/
spin_lock(&fs_info->balance_lock);
fs_info->balance_ctl->flags |= BTRFS_BALANCE_RESUME;
spin_unlock(&fs_info->balance_lock);
tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance");
return PTR_ERR_OR_ZERO(tsk);
}
int btrfs_recover_balance(struct btrfs_fs_info *fs_info)
{
struct btrfs_balance_control *bctl;
struct btrfs_balance_item *item;
struct btrfs_disk_balance_args disk_bargs;
struct btrfs_path *path;
struct extent_buffer *leaf;
struct btrfs_key key;
int ret;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = BTRFS_BALANCE_OBJECTID;
key.type = BTRFS_TEMPORARY_ITEM_KEY;
key.offset = 0;
ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
if (ret < 0)
goto out;
if (ret > 0) { /* ret = -ENOENT; */
ret = 0;
goto out;
}
bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
if (!bctl) {
ret = -ENOMEM;
goto out;
}
leaf = path->nodes[0];
item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
bctl->flags = btrfs_balance_flags(leaf, item);
bctl->flags |= BTRFS_BALANCE_RESUME;
btrfs_balance_data(leaf, item, &disk_bargs);
btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs);
btrfs_balance_meta(leaf, item, &disk_bargs);
btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs);
btrfs_balance_sys(leaf, item, &disk_bargs);
btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs);
/*
* This should never happen, as the paused balance state is recovered
* during mount without any chance of other exclusive ops to collide.
*
* This gives the exclusive op status to balance and keeps in paused
* state until user intervention (cancel or umount). If the ownership
* cannot be assigned, show a message but do not fail. The balance
* is in a paused state and must have fs_info::balance_ctl properly
* set up.
*/
if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED))
btrfs_warn(fs_info,
"balance: cannot set exclusive op status, resume manually");
btrfs_release_path(path);
mutex_lock(&fs_info->balance_mutex);
BUG_ON(fs_info->balance_ctl);
spin_lock(&fs_info->balance_lock);
fs_info->balance_ctl = bctl;
spin_unlock(&fs_info->balance_lock);
mutex_unlock(&fs_info->balance_mutex);
out:
btrfs_free_path(path);
return ret;
}
int btrfs_pause_balance(struct btrfs_fs_info *fs_info)
{
int ret = 0;
mutex_lock(&fs_info->balance_mutex);
if (!fs_info->balance_ctl) {
mutex_unlock(&fs_info->balance_mutex);
return -ENOTCONN;
}
if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
atomic_inc(&fs_info->balance_pause_req);
mutex_unlock(&fs_info->balance_mutex);
wait_event(fs_info->balance_wait_q,
!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
mutex_lock(&fs_info->balance_mutex);
/* we are good with balance_ctl ripped off from under us */
BUG_ON(test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
atomic_dec(&fs_info->balance_pause_req);
} else {
ret = -ENOTCONN;
}
mutex_unlock(&fs_info->balance_mutex);
return ret;
}
int btrfs_cancel_balance(struct btrfs_fs_info *fs_info)
{
mutex_lock(&fs_info->balance_mutex);
if (!fs_info->balance_ctl) {
mutex_unlock(&fs_info->balance_mutex);
return -ENOTCONN;
}
/*
* A paused balance with the item stored on disk can be resumed at
* mount time if the mount is read-write. Otherwise it's still paused
* and we must not allow cancelling as it deletes the item.
*/
if (sb_rdonly(fs_info->sb)) {
mutex_unlock(&fs_info->balance_mutex);
return -EROFS;
}
atomic_inc(&fs_info->balance_cancel_req);
/*
* if we are running just wait and return, balance item is
* deleted in btrfs_balance in this case
*/
if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
mutex_unlock(&fs_info->balance_mutex);
wait_event(fs_info->balance_wait_q,
!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
mutex_lock(&fs_info->balance_mutex);
} else {
mutex_unlock(&fs_info->balance_mutex);
/*
* Lock released to allow other waiters to continue, we'll
* reexamine the status again.
*/
mutex_lock(&fs_info->balance_mutex);
if (fs_info->balance_ctl) {
reset_balance_state(fs_info);
btrfs_exclop_finish(fs_info);
btrfs_info(fs_info, "balance: canceled");
}
}
ASSERT(!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
atomic_dec(&fs_info->balance_cancel_req);
mutex_unlock(&fs_info->balance_mutex);
return 0;
}
/*
* shrinking a device means finding all of the device extents past
* the new size, and then following the back refs to the chunks.
* The chunk relocation code actually frees the device extent
*/
int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
{
struct btrfs_fs_info *fs_info = device->fs_info;
struct btrfs_root *root = fs_info->dev_root;
struct btrfs_trans_handle *trans;
struct btrfs_dev_extent *dev_extent = NULL;
struct btrfs_path *path;
u64 length;
u64 chunk_offset;
int ret;
int slot;
int failed = 0;
bool retried = false;
struct extent_buffer *l;
struct btrfs_key key;
struct btrfs_super_block *super_copy = fs_info->super_copy;
u64 old_total = btrfs_super_total_bytes(super_copy);
u64 old_size = btrfs_device_get_total_bytes(device);
u64 diff;
u64 start;
u64 free_diff = 0;
new_size = round_down(new_size, fs_info->sectorsize);
start = new_size;
diff = round_down(old_size - new_size, fs_info->sectorsize);
if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state))
return -EINVAL;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
path->reada = READA_BACK;
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
btrfs_free_path(path);
return PTR_ERR(trans);
}
mutex_lock(&fs_info->chunk_mutex);
btrfs_device_set_total_bytes(device, new_size);
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
device->fs_devices->total_rw_bytes -= diff;
/*
* The new free_chunk_space is new_size - used, so we have to
* subtract the delta of the old free_chunk_space which included
* old_size - used. If used > new_size then just subtract this
* entire device's free space.
*/
if (device->bytes_used < new_size)
free_diff = (old_size - device->bytes_used) -
(new_size - device->bytes_used);
else
free_diff = old_size - device->bytes_used;
atomic64_sub(free_diff, &fs_info->free_chunk_space);
}
/*
* Once the device's size has been set to the new size, ensure all
* in-memory chunks are synced to disk so that the loop below sees them
* and relocates them accordingly.
*/
if (contains_pending_extent(device, &start, diff)) {
mutex_unlock(&fs_info->chunk_mutex);
ret = btrfs_commit_transaction(trans);
if (ret)
goto done;
} else {
mutex_unlock(&fs_info->chunk_mutex);
btrfs_end_transaction(trans);
}
again:
key.objectid = device->devid;
key.offset = (u64)-1;
key.type = BTRFS_DEV_EXTENT_KEY;
do {
mutex_lock(&fs_info->reclaim_bgs_lock);
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0) {
mutex_unlock(&fs_info->reclaim_bgs_lock);
goto done;
}
ret = btrfs_previous_item(root, path, 0, key.type);
if (ret) {
mutex_unlock(&fs_info->reclaim_bgs_lock);
if (ret < 0)
goto done;
ret = 0;
btrfs_release_path(path);
break;
}
l = path->nodes[0];
slot = path->slots[0];
btrfs_item_key_to_cpu(l, &key, path->slots[0]);
if (key.objectid != device->devid) {
mutex_unlock(&fs_info->reclaim_bgs_lock);
btrfs_release_path(path);
break;
}
dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
length = btrfs_dev_extent_length(l, dev_extent);
if (key.offset + length <= new_size) {
mutex_unlock(&fs_info->reclaim_bgs_lock);
btrfs_release_path(path);
break;
}
chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
btrfs_release_path(path);
/*
* We may be relocating the only data chunk we have,
* which could potentially end up with losing data's
* raid profile, so lets allocate an empty one in
* advance.
*/
ret = btrfs_may_alloc_data_chunk(fs_info, chunk_offset);
if (ret < 0) {
mutex_unlock(&fs_info->reclaim_bgs_lock);
goto done;
}
ret = btrfs_relocate_chunk(fs_info, chunk_offset);
mutex_unlock(&fs_info->reclaim_bgs_lock);
if (ret == -ENOSPC) {
failed++;
} else if (ret) {
if (ret == -ETXTBSY) {
btrfs_warn(fs_info,
"could not shrink block group %llu due to active swapfile",
chunk_offset);
}
goto done;
}
} while (key.offset-- > 0);
if (failed && !retried) {
failed = 0;
retried = true;
goto again;
} else if (failed && retried) {
ret = -ENOSPC;
goto done;
}
/* Shrinking succeeded, else we would be at "done". */
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
goto done;
}
mutex_lock(&fs_info->chunk_mutex);
/* Clear all state bits beyond the shrunk device size */
clear_extent_bits(&device->alloc_state, new_size, (u64)-1,
CHUNK_STATE_MASK);
btrfs_device_set_disk_total_bytes(device, new_size);
if (list_empty(&device->post_commit_list))
list_add_tail(&device->post_commit_list,
&trans->transaction->dev_update_list);
WARN_ON(diff > old_total);
btrfs_set_super_total_bytes(super_copy,
round_down(old_total - diff, fs_info->sectorsize));
mutex_unlock(&fs_info->chunk_mutex);
btrfs_reserve_chunk_metadata(trans, false);
/* Now btrfs_update_device() will change the on-disk size. */
ret = btrfs_update_device(trans, device);
btrfs_trans_release_chunk_metadata(trans);
if (ret < 0) {
btrfs_abort_transaction(trans, ret);
btrfs_end_transaction(trans);
} else {
ret = btrfs_commit_transaction(trans);
}
done:
btrfs_free_path(path);
if (ret) {
mutex_lock(&fs_info->chunk_mutex);
btrfs_device_set_total_bytes(device, old_size);
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
device->fs_devices->total_rw_bytes += diff;
atomic64_add(free_diff, &fs_info->free_chunk_space);
}
mutex_unlock(&fs_info->chunk_mutex);
}
return ret;
}
static int btrfs_add_system_chunk(struct btrfs_fs_info *fs_info,
struct btrfs_key *key,
struct btrfs_chunk *chunk, int item_size)
{
struct btrfs_super_block *super_copy = fs_info->super_copy;
struct btrfs_disk_key disk_key;
u32 array_size;
u8 *ptr;
lockdep_assert_held(&fs_info->chunk_mutex);
array_size = btrfs_super_sys_array_size(super_copy);
if (array_size + item_size + sizeof(disk_key)
> BTRFS_SYSTEM_CHUNK_ARRAY_SIZE)
return -EFBIG;
ptr = super_copy->sys_chunk_array + array_size;
btrfs_cpu_key_to_disk(&disk_key, key);
memcpy(ptr, &disk_key, sizeof(disk_key));
ptr += sizeof(disk_key);
memcpy(ptr, chunk, item_size);
item_size += sizeof(disk_key);
btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
return 0;
}
/*
* sort the devices in descending order by max_avail, total_avail
*/
static int btrfs_cmp_device_info(const void *a, const void *b)
{
const struct btrfs_device_info *di_a = a;
const struct btrfs_device_info *di_b = b;
if (di_a->max_avail > di_b->max_avail)
return -1;
if (di_a->max_avail < di_b->max_avail)
return 1;
if (di_a->total_avail > di_b->total_avail)
return -1;
if (di_a->total_avail < di_b->total_avail)
return 1;
return 0;
}
static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type)
{
if (!(type & BTRFS_BLOCK_GROUP_RAID56_MASK))
return;
btrfs_set_fs_incompat(info, RAID56);
}
static void check_raid1c34_incompat_flag(struct btrfs_fs_info *info, u64 type)
{
if (!(type & (BTRFS_BLOCK_GROUP_RAID1C3 | BTRFS_BLOCK_GROUP_RAID1C4)))
return;
btrfs_set_fs_incompat(info, RAID1C34);
}
/*
* Structure used internally for btrfs_create_chunk() function.
* Wraps needed parameters.
*/
struct alloc_chunk_ctl {
u64 start;
u64 type;
/* Total number of stripes to allocate */
int num_stripes;
/* sub_stripes info for map */
int sub_stripes;
/* Stripes per device */
int dev_stripes;
/* Maximum number of devices to use */
int devs_max;
/* Minimum number of devices to use */
int devs_min;
/* ndevs has to be a multiple of this */
int devs_increment;
/* Number of copies */
int ncopies;
/* Number of stripes worth of bytes to store parity information */
int nparity;
u64 max_stripe_size;
u64 max_chunk_size;
u64 dev_extent_min;
u64 stripe_size;
u64 chunk_size;
int ndevs;
};
static void init_alloc_chunk_ctl_policy_regular(
struct btrfs_fs_devices *fs_devices,
struct alloc_chunk_ctl *ctl)
{
struct btrfs_space_info *space_info;
space_info = btrfs_find_space_info(fs_devices->fs_info, ctl->type);
ASSERT(space_info);
ctl->max_chunk_size = READ_ONCE(space_info->chunk_size);
ctl->max_stripe_size = min_t(u64, ctl->max_chunk_size, SZ_1G);
if (ctl->type & BTRFS_BLOCK_GROUP_SYSTEM)
ctl->devs_max = min_t(int, ctl->devs_max, BTRFS_MAX_DEVS_SYS_CHUNK);
/* We don't want a chunk larger than 10% of writable space */
ctl->max_chunk_size = min(mult_perc(fs_devices->total_rw_bytes, 10),
ctl->max_chunk_size);
ctl->dev_extent_min = btrfs_stripe_nr_to_offset(ctl->dev_stripes);
}
static void init_alloc_chunk_ctl_policy_zoned(
struct btrfs_fs_devices *fs_devices,
struct alloc_chunk_ctl *ctl)
{
u64 zone_size = fs_devices->fs_info->zone_size;
u64 limit;
int min_num_stripes = ctl->devs_min * ctl->dev_stripes;
int min_data_stripes = (min_num_stripes - ctl->nparity) / ctl->ncopies;
u64 min_chunk_size = min_data_stripes * zone_size;
u64 type = ctl->type;
ctl->max_stripe_size = zone_size;
if (type & BTRFS_BLOCK_GROUP_DATA) {
ctl->max_chunk_size = round_down(BTRFS_MAX_DATA_CHUNK_SIZE,
zone_size);
} else if (type & BTRFS_BLOCK_GROUP_METADATA) {
ctl->max_chunk_size = ctl->max_stripe_size;
} else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
ctl->max_chunk_size = 2 * ctl->max_stripe_size;
ctl->devs_max = min_t(int, ctl->devs_max,
BTRFS_MAX_DEVS_SYS_CHUNK);
} else {
BUG();
}
/* We don't want a chunk larger than 10% of writable space */
limit = max(round_down(mult_perc(fs_devices->total_rw_bytes, 10),
zone_size),
min_chunk_size);
ctl->max_chunk_size = min(limit, ctl->max_chunk_size);
ctl->dev_extent_min = zone_size * ctl->dev_stripes;
}
static void init_alloc_chunk_ctl(struct btrfs_fs_devices *fs_devices,
struct alloc_chunk_ctl *ctl)
{
int index = btrfs_bg_flags_to_raid_index(ctl->type);
ctl->sub_stripes = btrfs_raid_array[index].sub_stripes;
ctl->dev_stripes = btrfs_raid_array[index].dev_stripes;
ctl->devs_max = btrfs_raid_array[index].devs_max;
if (!ctl->devs_max)
ctl->devs_max = BTRFS_MAX_DEVS(fs_devices->fs_info);
ctl->devs_min = btrfs_raid_array[index].devs_min;
ctl->devs_increment = btrfs_raid_array[index].devs_increment;
ctl->ncopies = btrfs_raid_array[index].ncopies;
ctl->nparity = btrfs_raid_array[index].nparity;
ctl->ndevs = 0;
switch (fs_devices->chunk_alloc_policy) {
case BTRFS_CHUNK_ALLOC_REGULAR:
init_alloc_chunk_ctl_policy_regular(fs_devices, ctl);
break;
case BTRFS_CHUNK_ALLOC_ZONED:
init_alloc_chunk_ctl_policy_zoned(fs_devices, ctl);
break;
default:
BUG();
}
}
static int gather_device_info(struct btrfs_fs_devices *fs_devices,
struct alloc_chunk_ctl *ctl,
struct btrfs_device_info *devices_info)
{
struct btrfs_fs_info *info = fs_devices->fs_info;
struct btrfs_device *device;
u64 total_avail;
u64 dev_extent_want = ctl->max_stripe_size * ctl->dev_stripes;
int ret;
int ndevs = 0;
u64 max_avail;
u64 dev_offset;
/*
* in the first pass through the devices list, we gather information
* about the available holes on each device.
*/
list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
WARN(1, KERN_ERR
"BTRFS: read-only device in alloc_list\n");
continue;
}
if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA,
&device->dev_state) ||
test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state))
continue;
if (device->total_bytes > device->bytes_used)
total_avail = device->total_bytes - device->bytes_used;
else
total_avail = 0;
/* If there is no space on this device, skip it. */
if (total_avail < ctl->dev_extent_min)
continue;
ret = find_free_dev_extent(device, dev_extent_want, &dev_offset,
&max_avail);
if (ret && ret != -ENOSPC)
return ret;
if (ret == 0)
max_avail = dev_extent_want;
if (max_avail < ctl->dev_extent_min) {
if (btrfs_test_opt(info, ENOSPC_DEBUG))
btrfs_debug(info,
"%s: devid %llu has no free space, have=%llu want=%llu",
__func__, device->devid, max_avail,
ctl->dev_extent_min);
continue;
}
if (ndevs == fs_devices->rw_devices) {
WARN(1, "%s: found more than %llu devices\n",
__func__, fs_devices->rw_devices);
break;
}
devices_info[ndevs].dev_offset = dev_offset;
devices_info[ndevs].max_avail = max_avail;
devices_info[ndevs].total_avail = total_avail;
devices_info[ndevs].dev = device;
++ndevs;
}
ctl->ndevs = ndevs;
/*
* now sort the devices by hole size / available space
*/
sort(devices_info, ndevs, sizeof(struct btrfs_device_info),
btrfs_cmp_device_info, NULL);
return 0;
}
static int decide_stripe_size_regular(struct alloc_chunk_ctl *ctl,
struct btrfs_device_info *devices_info)
{
/* Number of stripes that count for block group size */
int data_stripes;
/*
* The primary goal is to maximize the number of stripes, so use as
* many devices as possible, even if the stripes are not maximum sized.
*
* The DUP profile stores more than one stripe per device, the
* max_avail is the total size so we have to adjust.
*/
ctl->stripe_size = div_u64(devices_info[ctl->ndevs - 1].max_avail,
ctl->dev_stripes);
ctl->num_stripes = ctl->ndevs * ctl->dev_stripes;
/* This will have to be fixed for RAID1 and RAID10 over more drives */
data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies;
/*
* Use the number of data stripes to figure out how big this chunk is
* really going to be in terms of logical address space, and compare
* that answer with the max chunk size. If it's higher, we try to
* reduce stripe_size.
*/
if (ctl->stripe_size * data_stripes > ctl->max_chunk_size) {
/*
* Reduce stripe_size, round it up to a 16MB boundary again and
* then use it, unless it ends up being even bigger than the
* previous value we had already.
*/
ctl->stripe_size = min(round_up(div_u64(ctl->max_chunk_size,
data_stripes), SZ_16M),
ctl->stripe_size);
}
/* Stripe size should not go beyond 1G. */
ctl->stripe_size = min_t(u64, ctl->stripe_size, SZ_1G);
/* Align to BTRFS_STRIPE_LEN */
ctl->stripe_size = round_down(ctl->stripe_size, BTRFS_STRIPE_LEN);
ctl->chunk_size = ctl->stripe_size * data_stripes;
return 0;
}
static int decide_stripe_size_zoned(struct alloc_chunk_ctl *ctl,
struct btrfs_device_info *devices_info)
{
u64 zone_size = devices_info[0].dev->zone_info->zone_size;
/* Number of stripes that count for block group size */
int data_stripes;
/*
* It should hold because:
* dev_extent_min == dev_extent_want == zone_size * dev_stripes
*/
ASSERT(devices_info[ctl->ndevs - 1].max_avail == ctl->dev_extent_min);
ctl->stripe_size = zone_size;
ctl->num_stripes = ctl->ndevs * ctl->dev_stripes;
data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies;
/* stripe_size is fixed in zoned filesystem. Reduce ndevs instead. */
if (ctl->stripe_size * data_stripes > ctl->max_chunk_size) {
ctl->ndevs = div_u64(div_u64(ctl->max_chunk_size * ctl->ncopies,
ctl->stripe_size) + ctl->nparity,
ctl->dev_stripes);
ctl->num_stripes = ctl->ndevs * ctl->dev_stripes;
data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies;
ASSERT(ctl->stripe_size * data_stripes <= ctl->max_chunk_size);
}
ctl->chunk_size = ctl->stripe_size * data_stripes;
return 0;
}
static int decide_stripe_size(struct btrfs_fs_devices *fs_devices,
struct alloc_chunk_ctl *ctl,
struct btrfs_device_info *devices_info)
{
struct btrfs_fs_info *info = fs_devices->fs_info;
/*
* Round down to number of usable stripes, devs_increment can be any
* number so we can't use round_down() that requires power of 2, while
* rounddown is safe.
*/
ctl->ndevs = rounddown(ctl->ndevs, ctl->devs_increment);
if (ctl->ndevs < ctl->devs_min) {
if (btrfs_test_opt(info, ENOSPC_DEBUG)) {
btrfs_debug(info,
"%s: not enough devices with free space: have=%d minimum required=%d",
__func__, ctl->ndevs, ctl->devs_min);
}
return -ENOSPC;
}
ctl->ndevs = min(ctl->ndevs, ctl->devs_max);
switch (fs_devices->chunk_alloc_policy) {
case BTRFS_CHUNK_ALLOC_REGULAR:
return decide_stripe_size_regular(ctl, devices_info);
case BTRFS_CHUNK_ALLOC_ZONED:
return decide_stripe_size_zoned(ctl, devices_info);
default:
BUG();
}
}
static void chunk_map_device_set_bits(struct btrfs_chunk_map *map, unsigned int bits)
{
for (int i = 0; i < map->num_stripes; i++) {
struct btrfs_io_stripe *stripe = &map->stripes[i];
struct btrfs_device *device = stripe->dev;
set_extent_bit(&device->alloc_state, stripe->physical,
stripe->physical + map->stripe_size - 1,
bits | EXTENT_NOWAIT, NULL);
}
}
static void chunk_map_device_clear_bits(struct btrfs_chunk_map *map, unsigned int bits)
{
for (int i = 0; i < map->num_stripes; i++) {
struct btrfs_io_stripe *stripe = &map->stripes[i];
struct btrfs_device *device = stripe->dev;
__clear_extent_bit(&device->alloc_state, stripe->physical,
stripe->physical + map->stripe_size - 1,
bits | EXTENT_NOWAIT,
NULL, NULL);
}
}
void btrfs_remove_chunk_map(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map)
{
write_lock(&fs_info->mapping_tree_lock);
rb_erase_cached(&map->rb_node, &fs_info->mapping_tree);
RB_CLEAR_NODE(&map->rb_node);
chunk_map_device_clear_bits(map, CHUNK_ALLOCATED);
write_unlock(&fs_info->mapping_tree_lock);
/* Once for the tree reference. */
btrfs_free_chunk_map(map);
}
EXPORT_FOR_TESTS
int btrfs_add_chunk_map(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map)
{
struct rb_node **p;
struct rb_node *parent = NULL;
bool leftmost = true;
write_lock(&fs_info->mapping_tree_lock);
p = &fs_info->mapping_tree.rb_root.rb_node;
while (*p) {
struct btrfs_chunk_map *entry;
parent = *p;
entry = rb_entry(parent, struct btrfs_chunk_map, rb_node);
if (map->start < entry->start) {
p = &(*p)->rb_left;
} else if (map->start > entry->start) {
p = &(*p)->rb_right;
leftmost = false;
} else {
write_unlock(&fs_info->mapping_tree_lock);
return -EEXIST;
}
}
rb_link_node(&map->rb_node, parent, p);
rb_insert_color_cached(&map->rb_node, &fs_info->mapping_tree, leftmost);
chunk_map_device_set_bits(map, CHUNK_ALLOCATED);
chunk_map_device_clear_bits(map, CHUNK_TRIMMED);
write_unlock(&fs_info->mapping_tree_lock);
return 0;
}
EXPORT_FOR_TESTS
struct btrfs_chunk_map *btrfs_alloc_chunk_map(int num_stripes, gfp_t gfp)
{
struct btrfs_chunk_map *map;
map = kmalloc(btrfs_chunk_map_size(num_stripes), gfp);
if (!map)
return NULL;
refcount_set(&map->refs, 1);
RB_CLEAR_NODE(&map->rb_node);
return map;
}
static struct btrfs_block_group *create_chunk(struct btrfs_trans_handle *trans,
struct alloc_chunk_ctl *ctl,
struct btrfs_device_info *devices_info)
{
struct btrfs_fs_info *info = trans->fs_info;
struct btrfs_chunk_map *map;
struct btrfs_block_group *block_group;
u64 start = ctl->start;
u64 type = ctl->type;
int ret;
map = btrfs_alloc_chunk_map(ctl->num_stripes, GFP_NOFS);
if (!map)
return ERR_PTR(-ENOMEM);
map->start = start;
map->chunk_len = ctl->chunk_size;
map->stripe_size = ctl->stripe_size;
map->type = type;
map->io_align = BTRFS_STRIPE_LEN;
map->io_width = BTRFS_STRIPE_LEN;
map->sub_stripes = ctl->sub_stripes;
map->num_stripes = ctl->num_stripes;
for (int i = 0; i < ctl->ndevs; i++) {
for (int j = 0; j < ctl->dev_stripes; j++) {
int s = i * ctl->dev_stripes + j;
map->stripes[s].dev = devices_info[i].dev;
map->stripes[s].physical = devices_info[i].dev_offset +
j * ctl->stripe_size;
}
}
trace_btrfs_chunk_alloc(info, map, start, ctl->chunk_size);
ret = btrfs_add_chunk_map(info, map);
if (ret) {
btrfs_free_chunk_map(map);
return ERR_PTR(ret);
}
block_group = btrfs_make_block_group(trans, type, start, ctl->chunk_size);
if (IS_ERR(block_group)) {
btrfs_remove_chunk_map(info, map);
return block_group;
}
for (int i = 0; i < map->num_stripes; i++) {
struct btrfs_device *dev = map->stripes[i].dev;
btrfs_device_set_bytes_used(dev,
dev->bytes_used + ctl->stripe_size);
if (list_empty(&dev->post_commit_list))
list_add_tail(&dev->post_commit_list,
&trans->transaction->dev_update_list);
}
atomic64_sub(ctl->stripe_size * map->num_stripes,
&info->free_chunk_space);
check_raid56_incompat_flag(info, type);
check_raid1c34_incompat_flag(info, type);
return block_group;
}
struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans,
u64 type)
{
struct btrfs_fs_info *info = trans->fs_info;
struct btrfs_fs_devices *fs_devices = info->fs_devices;
struct btrfs_device_info *devices_info = NULL;
struct alloc_chunk_ctl ctl;
struct btrfs_block_group *block_group;
int ret;
lockdep_assert_held(&info->chunk_mutex);
if (!alloc_profile_is_valid(type, 0)) {
ASSERT(0);
return ERR_PTR(-EINVAL);
}
if (list_empty(&fs_devices->alloc_list)) {
if (btrfs_test_opt(info, ENOSPC_DEBUG))
btrfs_debug(info, "%s: no writable device", __func__);
return ERR_PTR(-ENOSPC);
}
if (!(type & BTRFS_BLOCK_GROUP_TYPE_MASK)) {
btrfs_err(info, "invalid chunk type 0x%llx requested", type);
ASSERT(0);
return ERR_PTR(-EINVAL);
}
ctl.start = find_next_chunk(info);
ctl.type = type;
init_alloc_chunk_ctl(fs_devices, &ctl);
devices_info = kcalloc(fs_devices->rw_devices, sizeof(*devices_info),
GFP_NOFS);
if (!devices_info)
return ERR_PTR(-ENOMEM);
ret = gather_device_info(fs_devices, &ctl, devices_info);
if (ret < 0) {
block_group = ERR_PTR(ret);
goto out;
}
ret = decide_stripe_size(fs_devices, &ctl, devices_info);
if (ret < 0) {
block_group = ERR_PTR(ret);
goto out;
}
block_group = create_chunk(trans, &ctl, devices_info);
out:
kfree(devices_info);
return block_group;
}
/*
* This function, btrfs_chunk_alloc_add_chunk_item(), typically belongs to the
* phase 1 of chunk allocation. It belongs to phase 2 only when allocating system
* chunks.
*
* See the comment at btrfs_chunk_alloc() for details about the chunk allocation
* phases.
*/
int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans,
struct btrfs_block_group *bg)
{
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_root *chunk_root = fs_info->chunk_root;
struct btrfs_key key;
struct btrfs_chunk *chunk;
struct btrfs_stripe *stripe;
struct btrfs_chunk_map *map;
size_t item_size;
int i;
int ret;
/*
* We take the chunk_mutex for 2 reasons:
*
* 1) Updates and insertions in the chunk btree must be done while holding
* the chunk_mutex, as well as updating the system chunk array in the
* superblock. See the comment on top of btrfs_chunk_alloc() for the
* details;
*
* 2) To prevent races with the final phase of a device replace operation
* that replaces the device object associated with the map's stripes,
* because the device object's id can change at any time during that
* final phase of the device replace operation
* (dev-replace.c:btrfs_dev_replace_finishing()), so we could grab the
* replaced device and then see it with an ID of BTRFS_DEV_REPLACE_DEVID,
* which would cause a failure when updating the device item, which does
* not exists, or persisting a stripe of the chunk item with such ID.
* Here we can't use the device_list_mutex because our caller already
* has locked the chunk_mutex, and the final phase of device replace
* acquires both mutexes - first the device_list_mutex and then the
* chunk_mutex. Using any of those two mutexes protects us from a
* concurrent device replace.
*/
lockdep_assert_held(&fs_info->chunk_mutex);
map = btrfs_get_chunk_map(fs_info, bg->start, bg->length);
if (IS_ERR(map)) {
ret = PTR_ERR(map);
btrfs_abort_transaction(trans, ret);
return ret;
}
item_size = btrfs_chunk_item_size(map->num_stripes);
chunk = kzalloc(item_size, GFP_NOFS);
if (!chunk) {
ret = -ENOMEM;
btrfs_abort_transaction(trans, ret);
goto out;
}
for (i = 0; i < map->num_stripes; i++) {
struct btrfs_device *device = map->stripes[i].dev;
ret = btrfs_update_device(trans, device);
if (ret)
goto out;
}
stripe = &chunk->stripe;
for (i = 0; i < map->num_stripes; i++) {
struct btrfs_device *device = map->stripes[i].dev;
const u64 dev_offset = map->stripes[i].physical;
btrfs_set_stack_stripe_devid(stripe, device->devid);
btrfs_set_stack_stripe_offset(stripe, dev_offset);
memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
stripe++;
}
btrfs_set_stack_chunk_length(chunk, bg->length);
btrfs_set_stack_chunk_owner(chunk, BTRFS_EXTENT_TREE_OBJECTID);
btrfs_set_stack_chunk_stripe_len(chunk, BTRFS_STRIPE_LEN);
btrfs_set_stack_chunk_type(chunk, map->type);
btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
btrfs_set_stack_chunk_io_align(chunk, BTRFS_STRIPE_LEN);
btrfs_set_stack_chunk_io_width(chunk, BTRFS_STRIPE_LEN);
btrfs_set_stack_chunk_sector_size(chunk, fs_info->sectorsize);
btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
key.type = BTRFS_CHUNK_ITEM_KEY;
key.offset = bg->start;
ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
if (ret)
goto out;
set_bit(BLOCK_GROUP_FLAG_CHUNK_ITEM_INSERTED, &bg->runtime_flags);
if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
ret = btrfs_add_system_chunk(fs_info, &key, chunk, item_size);
if (ret)
goto out;
}
out:
kfree(chunk);
btrfs_free_chunk_map(map);
return ret;
}
static noinline int init_first_rw_device(struct btrfs_trans_handle *trans)
{
struct btrfs_fs_info *fs_info = trans->fs_info;
u64 alloc_profile;
struct btrfs_block_group *meta_bg;
struct btrfs_block_group *sys_bg;
/*
* When adding a new device for sprouting, the seed device is read-only
* so we must first allocate a metadata and a system chunk. But before
* adding the block group items to the extent, device and chunk btrees,
* we must first:
*
* 1) Create both chunks without doing any changes to the btrees, as
* otherwise we would get -ENOSPC since the block groups from the
* seed device are read-only;
*
* 2) Add the device item for the new sprout device - finishing the setup
* of a new block group requires updating the device item in the chunk
* btree, so it must exist when we attempt to do it. The previous step
* ensures this does not fail with -ENOSPC.
*
* After that we can add the block group items to their btrees:
* update existing device item in the chunk btree, add a new block group
* item to the extent btree, add a new chunk item to the chunk btree and
* finally add the new device extent items to the devices btree.
*/
alloc_profile = btrfs_metadata_alloc_profile(fs_info);
meta_bg = btrfs_create_chunk(trans, alloc_profile);
if (IS_ERR(meta_bg))
return PTR_ERR(meta_bg);
alloc_profile = btrfs_system_alloc_profile(fs_info);
sys_bg = btrfs_create_chunk(trans, alloc_profile);
if (IS_ERR(sys_bg))
return PTR_ERR(sys_bg);
return 0;
}
static inline int btrfs_chunk_max_errors(struct btrfs_chunk_map *map)
{
const int index = btrfs_bg_flags_to_raid_index(map->type);
return btrfs_raid_array[index].tolerated_failures;
}
bool btrfs_chunk_writeable(struct btrfs_fs_info *fs_info, u64 chunk_offset)
{
struct btrfs_chunk_map *map;
int miss_ndevs = 0;
int i;
bool ret = true;
map = btrfs_get_chunk_map(fs_info, chunk_offset, 1);
if (IS_ERR(map))
return false;
for (i = 0; i < map->num_stripes; i++) {
if (test_bit(BTRFS_DEV_STATE_MISSING,
&map->stripes[i].dev->dev_state)) {
miss_ndevs++;
continue;
}
if (!test_bit(BTRFS_DEV_STATE_WRITEABLE,
&map->stripes[i].dev->dev_state)) {
ret = false;
goto end;
}
}
/*
* If the number of missing devices is larger than max errors, we can
* not write the data into that chunk successfully.
*/
if (miss_ndevs > btrfs_chunk_max_errors(map))
ret = false;
end:
btrfs_free_chunk_map(map);
return ret;
}
void btrfs_mapping_tree_free(struct btrfs_fs_info *fs_info)
{
write_lock(&fs_info->mapping_tree_lock);
while (!RB_EMPTY_ROOT(&fs_info->mapping_tree.rb_root)) {
struct btrfs_chunk_map *map;
struct rb_node *node;
node = rb_first_cached(&fs_info->mapping_tree);
map = rb_entry(node, struct btrfs_chunk_map, rb_node);
rb_erase_cached(&map->rb_node, &fs_info->mapping_tree);
RB_CLEAR_NODE(&map->rb_node);
chunk_map_device_clear_bits(map, CHUNK_ALLOCATED);
/* Once for the tree ref. */
btrfs_free_chunk_map(map);
cond_resched_rwlock_write(&fs_info->mapping_tree_lock);
}
write_unlock(&fs_info->mapping_tree_lock);
}
static int btrfs_chunk_map_num_copies(const struct btrfs_chunk_map *map)
{
enum btrfs_raid_types index = btrfs_bg_flags_to_raid_index(map->type);
if (map->type & BTRFS_BLOCK_GROUP_RAID5)
return 2;
/*
* There could be two corrupted data stripes, we need to loop retry in
* order to rebuild the correct data.
*
* Fail a stripe at a time on every retry except the stripe under
* reconstruction.
*/
if (map->type & BTRFS_BLOCK_GROUP_RAID6)
return map->num_stripes;
/* Non-RAID56, use their ncopies from btrfs_raid_array. */
return btrfs_raid_array[index].ncopies;
}
int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
{
struct btrfs_chunk_map *map;
int ret;
map = btrfs_get_chunk_map(fs_info, logical, len);
if (IS_ERR(map))
/*
* We could return errors for these cases, but that could get
* ugly and we'd probably do the same thing which is just not do
* anything else and exit, so return 1 so the callers don't try
* to use other copies.
*/
return 1;
ret = btrfs_chunk_map_num_copies(map);
btrfs_free_chunk_map(map);
return ret;
}
unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
u64 logical)
{
struct btrfs_chunk_map *map;
unsigned long len = fs_info->sectorsize;
if (!btrfs_fs_incompat(fs_info, RAID56))
return len;
map = btrfs_get_chunk_map(fs_info, logical, len);
if (!WARN_ON(IS_ERR(map))) {
if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
len = btrfs_stripe_nr_to_offset(nr_data_stripes(map));
btrfs_free_chunk_map(map);
}
return len;
}
static int find_live_mirror(struct btrfs_fs_info *fs_info,
struct btrfs_chunk_map *map, int first,
int dev_replace_is_ongoing)
{
const enum btrfs_read_policy policy = READ_ONCE(fs_info->fs_devices->read_policy);
int i;
int num_stripes;
int preferred_mirror;
int tolerance;
struct btrfs_device *srcdev;
ASSERT((map->type &
(BTRFS_BLOCK_GROUP_RAID1_MASK | BTRFS_BLOCK_GROUP_RAID10)));
if (map->type & BTRFS_BLOCK_GROUP_RAID10)
num_stripes = map->sub_stripes;
else
num_stripes = map->num_stripes;
switch (policy) {
default:
/* Shouldn't happen, just warn and use pid instead of failing */
btrfs_warn_rl(fs_info, "unknown read_policy type %u, reset to pid",
policy);
WRITE_ONCE(fs_info->fs_devices->read_policy, BTRFS_READ_POLICY_PID);
fallthrough;
case BTRFS_READ_POLICY_PID:
preferred_mirror = first + (current->pid % num_stripes);
break;
}
if (dev_replace_is_ongoing &&
fs_info->dev_replace.cont_reading_from_srcdev_mode ==
BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID)
srcdev = fs_info->dev_replace.srcdev;
else
srcdev = NULL;
/*
* try to avoid the drive that is the source drive for a
* dev-replace procedure, only choose it if no other non-missing
* mirror is available
*/
for (tolerance = 0; tolerance < 2; tolerance++) {
if (map->stripes[preferred_mirror].dev->bdev &&
(tolerance || map->stripes[preferred_mirror].dev != srcdev))
return preferred_mirror;
for (i = first; i < first + num_stripes; i++) {
if (map->stripes[i].dev->bdev &&
(tolerance || map->stripes[i].dev != srcdev))
return i;
}
}
/* we couldn't find one that doesn't fail. Just return something
* and the io error handling code will clean up eventually
*/
return preferred_mirror;
}
EXPORT_FOR_TESTS
struct btrfs_io_context *alloc_btrfs_io_context(struct btrfs_fs_info *fs_info,
u64 logical, u16 total_stripes)
{
struct btrfs_io_context *bioc;
bioc = kzalloc(
/* The size of btrfs_io_context */
sizeof(struct btrfs_io_context) +
/* Plus the variable array for the stripes */
sizeof(struct btrfs_io_stripe) * (total_stripes),
GFP_NOFS);
if (!bioc)
return NULL;
refcount_set(&bioc->refs, 1);
bioc->fs_info = fs_info;
bioc->replace_stripe_src = -1;
bioc->full_stripe_logical = (u64)-1;
bioc->logical = logical;
return bioc;
}
void btrfs_get_bioc(struct btrfs_io_context *bioc)
{
WARN_ON(!refcount_read(&bioc->refs));
refcount_inc(&bioc->refs);
}
void btrfs_put_bioc(struct btrfs_io_context *bioc)
{
if (!bioc)
return;
if (refcount_dec_and_test(&bioc->refs))
kfree(bioc);
}
/*
* Please note that, discard won't be sent to target device of device
* replace.
*/
struct btrfs_discard_stripe *btrfs_map_discard(struct btrfs_fs_info *fs_info,
u64 logical, u64 *length_ret,
u32 *num_stripes)
{
struct btrfs_chunk_map *map;
struct btrfs_discard_stripe *stripes;
u64 length = *length_ret;
u64 offset;
u32 stripe_nr;
u32 stripe_nr_end;
u32 stripe_cnt;
u64 stripe_end_offset;
u64 stripe_offset;
u32 stripe_index;
u32 factor = 0;
u32 sub_stripes = 0;
u32 stripes_per_dev = 0;
u32 remaining_stripes = 0;
u32 last_stripe = 0;
int ret;
int i;
map = btrfs_get_chunk_map(fs_info, logical, length);
if (IS_ERR(map))
return ERR_CAST(map);
/* we don't discard raid56 yet */
if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
ret = -EOPNOTSUPP;
goto out_free_map;
}
offset = logical - map->start;
length = min_t(u64, map->start + map->chunk_len - logical, length);
*length_ret = length;
/*
* stripe_nr counts the total number of stripes we have to stride
* to get to this block
*/
stripe_nr = offset >> BTRFS_STRIPE_LEN_SHIFT;
/* stripe_offset is the offset of this block in its stripe */
stripe_offset = offset - btrfs_stripe_nr_to_offset(stripe_nr);
stripe_nr_end = round_up(offset + length, BTRFS_STRIPE_LEN) >>
BTRFS_STRIPE_LEN_SHIFT;
stripe_cnt = stripe_nr_end - stripe_nr;
stripe_end_offset = btrfs_stripe_nr_to_offset(stripe_nr_end) -
(offset + length);
/*
* after this, stripe_nr is the number of stripes on this
* device we have to walk to find the data, and stripe_index is
* the number of our device in the stripe array
*/
*num_stripes = 1;
stripe_index = 0;
if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
BTRFS_BLOCK_GROUP_RAID10)) {
if (map->type & BTRFS_BLOCK_GROUP_RAID0)
sub_stripes = 1;
else
sub_stripes = map->sub_stripes;
factor = map->num_stripes / sub_stripes;
*num_stripes = min_t(u64, map->num_stripes,
sub_stripes * stripe_cnt);
stripe_index = stripe_nr % factor;
stripe_nr /= factor;
stripe_index *= sub_stripes;
remaining_stripes = stripe_cnt % factor;
stripes_per_dev = stripe_cnt / factor;
last_stripe = ((stripe_nr_end - 1) % factor) * sub_stripes;
} else if (map->type & (BTRFS_BLOCK_GROUP_RAID1_MASK |
BTRFS_BLOCK_GROUP_DUP)) {
*num_stripes = map->num_stripes;
} else {
stripe_index = stripe_nr % map->num_stripes;
stripe_nr /= map->num_stripes;
}
stripes = kcalloc(*num_stripes, sizeof(*stripes), GFP_NOFS);
if (!stripes) {
ret = -ENOMEM;
goto out_free_map;
}
for (i = 0; i < *num_stripes; i++) {
stripes[i].physical =
map->stripes[stripe_index].physical +
stripe_offset + btrfs_stripe_nr_to_offset(stripe_nr);
stripes[i].dev = map->stripes[stripe_index].dev;
if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
BTRFS_BLOCK_GROUP_RAID10)) {
stripes[i].length = btrfs_stripe_nr_to_offset(stripes_per_dev);
if (i / sub_stripes < remaining_stripes)
stripes[i].length += BTRFS_STRIPE_LEN;
/*
* Special for the first stripe and
* the last stripe:
*
* |-------|...|-------|
* |----------|
* off end_off
*/
if (i < sub_stripes)
stripes[i].length -= stripe_offset;
if (stripe_index >= last_stripe &&
stripe_index <= (last_stripe +
sub_stripes - 1))
stripes[i].length -= stripe_end_offset;
if (i == sub_stripes - 1)
stripe_offset = 0;
} else {
stripes[i].length = length;
}
stripe_index++;
if (stripe_index == map->num_stripes) {
stripe_index = 0;
stripe_nr++;
}
}
btrfs_free_chunk_map(map);
return stripes;
out_free_map:
btrfs_free_chunk_map(map);
return ERR_PTR(ret);
}
static bool is_block_group_to_copy(struct btrfs_fs_info *fs_info, u64 logical)
{
struct btrfs_block_group *cache;
bool ret;
/* Non zoned filesystem does not use "to_copy" flag */
if (!btrfs_is_zoned(fs_info))
return false;
cache = btrfs_lookup_block_group(fs_info, logical);
ret = test_bit(BLOCK_GROUP_FLAG_TO_COPY, &cache->runtime_flags);
btrfs_put_block_group(cache);
return ret;
}
static void handle_ops_on_dev_replace(struct btrfs_io_context *bioc,
struct btrfs_dev_replace *dev_replace,
u64 logical,
struct btrfs_io_geometry *io_geom)
{
u64 srcdev_devid = dev_replace->srcdev->devid;
/*
* At this stage, num_stripes is still the real number of stripes,
* excluding the duplicated stripes.
*/
int num_stripes = io_geom->num_stripes;
int max_errors = io_geom->max_errors;
int nr_extra_stripes = 0;
int i;
/*
* A block group which has "to_copy" set will eventually be copied by
* the dev-replace process. We can avoid cloning IO here.
*/
if (is_block_group_to_copy(dev_replace->srcdev->fs_info, logical))
return;
/*
* Duplicate the write operations while the dev-replace procedure is
* running. Since the copying of the old disk to the new disk takes
* place at run time while the filesystem is mounted writable, the
* regular write operations to the old disk have to be duplicated to go
* to the new disk as well.
*
* Note that device->missing is handled by the caller, and that the
* write to the old disk is already set up in the stripes array.
*/
for (i = 0; i < num_stripes; i++) {
struct btrfs_io_stripe *old = &bioc->stripes[i];
struct btrfs_io_stripe *new = &bioc->stripes[num_stripes + nr_extra_stripes];
if (old->dev->devid != srcdev_devid)
continue;
new->physical = old->physical;
new->dev = dev_replace->tgtdev;
if (bioc->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK)
bioc->replace_stripe_src = i;
nr_extra_stripes++;
}
/* We can only have at most 2 extra nr_stripes (for DUP). */
ASSERT(nr_extra_stripes <= 2);
/*
* For GET_READ_MIRRORS, we can only return at most 1 extra stripe for
* replace.
* If we have 2 extra stripes, only choose the one with smaller physical.
*/
if (io_geom->op == BTRFS_MAP_GET_READ_MIRRORS && nr_extra_stripes == 2) {
struct btrfs_io_stripe *first = &bioc->stripes[num_stripes];
struct btrfs_io_stripe *second = &bioc->stripes[num_stripes + 1];
/* Only DUP can have two extra stripes. */
ASSERT(bioc->map_type & BTRFS_BLOCK_GROUP_DUP);
/*
* Swap the last stripe stripes and reduce @nr_extra_stripes.
* The extra stripe would still be there, but won't be accessed.
*/
if (first->physical > second->physical) {
swap(second->physical, first->physical);
swap(second->dev, first->dev);
nr_extra_stripes--;
}
}
io_geom->num_stripes = num_stripes + nr_extra_stripes;
io_geom->max_errors = max_errors + nr_extra_stripes;
bioc->replace_nr_stripes = nr_extra_stripes;
}
static u64 btrfs_max_io_len(struct btrfs_chunk_map *map, u64 offset,
struct btrfs_io_geometry *io_geom)
{
/*
* Stripe_nr is the stripe where this block falls. stripe_offset is
* the offset of this block in its stripe.
*/
io_geom->stripe_offset = offset & BTRFS_STRIPE_LEN_MASK;
io_geom->stripe_nr = offset >> BTRFS_STRIPE_LEN_SHIFT;
ASSERT(io_geom->stripe_offset < U32_MAX);
if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
unsigned long full_stripe_len =
btrfs_stripe_nr_to_offset(nr_data_stripes(map));
/*
* For full stripe start, we use previously calculated
* @stripe_nr. Align it to nr_data_stripes, then multiply with
* STRIPE_LEN.
*
* By this we can avoid u64 division completely. And we have
* to go rounddown(), not round_down(), as nr_data_stripes is
* not ensured to be power of 2.
*/
io_geom->raid56_full_stripe_start = btrfs_stripe_nr_to_offset(
rounddown(io_geom->stripe_nr, nr_data_stripes(map)));
ASSERT(io_geom->raid56_full_stripe_start + full_stripe_len > offset);
ASSERT(io_geom->raid56_full_stripe_start <= offset);
/*
* For writes to RAID56, allow to write a full stripe set, but
* no straddling of stripe sets.
*/
if (io_geom->op == BTRFS_MAP_WRITE)
return full_stripe_len - (offset - io_geom->raid56_full_stripe_start);
}
/*
* For other RAID types and for RAID56 reads, allow a single stripe (on
* a single disk).
*/
if (map->type & BTRFS_BLOCK_GROUP_STRIPE_MASK)
return BTRFS_STRIPE_LEN - io_geom->stripe_offset;
return U64_MAX;
}
static int set_io_stripe(struct btrfs_fs_info *fs_info, u64 logical,
u64 *length, struct btrfs_io_stripe *dst,
struct btrfs_chunk_map *map,
struct btrfs_io_geometry *io_geom)
{
dst->dev = map->stripes[io_geom->stripe_index].dev;
if (io_geom->op == BTRFS_MAP_READ &&
btrfs_need_stripe_tree_update(fs_info, map->type))
return btrfs_get_raid_extent_offset(fs_info, logical, length,
map->type,
io_geom->stripe_index, dst);
dst->physical = map->stripes[io_geom->stripe_index].physical +
io_geom->stripe_offset +
btrfs_stripe_nr_to_offset(io_geom->stripe_nr);
return 0;
}
static bool is_single_device_io(struct btrfs_fs_info *fs_info,
const struct btrfs_io_stripe *smap,
const struct btrfs_chunk_map *map,
int num_alloc_stripes,
enum btrfs_map_op op, int mirror_num)
{
if (!smap)
return false;
if (num_alloc_stripes != 1)
return false;
if (btrfs_need_stripe_tree_update(fs_info, map->type) && op != BTRFS_MAP_READ)
return false;
if ((map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) && mirror_num > 1)
return false;
return true;
}
static void map_blocks_raid0(const struct btrfs_chunk_map *map,
struct btrfs_io_geometry *io_geom)
{
io_geom->stripe_index = io_geom->stripe_nr % map->num_stripes;
io_geom->stripe_nr /= map->num_stripes;
if (io_geom->op == BTRFS_MAP_READ)
io_geom->mirror_num = 1;
}
static void map_blocks_raid1(struct btrfs_fs_info *fs_info,
struct btrfs_chunk_map *map,
struct btrfs_io_geometry *io_geom,
bool dev_replace_is_ongoing)
{
if (io_geom->op != BTRFS_MAP_READ) {
io_geom->num_stripes = map->num_stripes;
return;
}
if (io_geom->mirror_num) {
io_geom->stripe_index = io_geom->mirror_num - 1;
return;
}
io_geom->stripe_index = find_live_mirror(fs_info, map, 0,
dev_replace_is_ongoing);
io_geom->mirror_num = io_geom->stripe_index + 1;
}
static void map_blocks_dup(const struct btrfs_chunk_map *map,
struct btrfs_io_geometry *io_geom)
{
if (io_geom->op != BTRFS_MAP_READ) {
io_geom->num_stripes = map->num_stripes;
return;
}
if (io_geom->mirror_num) {
io_geom->stripe_index = io_geom->mirror_num - 1;
return;
}
io_geom->mirror_num = 1;
}
static void map_blocks_raid10(struct btrfs_fs_info *fs_info,
struct btrfs_chunk_map *map,
struct btrfs_io_geometry *io_geom,
bool dev_replace_is_ongoing)
{
u32 factor = map->num_stripes / map->sub_stripes;
int old_stripe_index;
io_geom->stripe_index = (io_geom->stripe_nr % factor) * map->sub_stripes;
io_geom->stripe_nr /= factor;
if (io_geom->op != BTRFS_MAP_READ) {
io_geom->num_stripes = map->sub_stripes;
return;
}
if (io_geom->mirror_num) {
io_geom->stripe_index += io_geom->mirror_num - 1;
return;
}
old_stripe_index = io_geom->stripe_index;
io_geom->stripe_index = find_live_mirror(fs_info, map,
io_geom->stripe_index,
dev_replace_is_ongoing);
io_geom->mirror_num = io_geom->stripe_index - old_stripe_index + 1;
}
static void map_blocks_raid56_write(struct btrfs_chunk_map *map,
struct btrfs_io_geometry *io_geom,
u64 logical, u64 *length)
{
int data_stripes = nr_data_stripes(map);
/*
* Needs full stripe mapping.
*
* Push stripe_nr back to the start of the full stripe For those cases
* needing a full stripe, @stripe_nr is the full stripe number.
*
* Originally we go raid56_full_stripe_start / full_stripe_len, but
* that can be expensive. Here we just divide @stripe_nr with
* @data_stripes.
*/
io_geom->stripe_nr /= data_stripes;
/* RAID[56] write or recovery. Return all stripes */
io_geom->num_stripes = map->num_stripes;
io_geom->max_errors = btrfs_chunk_max_errors(map);
/* Return the length to the full stripe end. */
*length = min(logical + *length,
io_geom->raid56_full_stripe_start + map->start +
btrfs_stripe_nr_to_offset(data_stripes)) -
logical;
io_geom->stripe_index = 0;
io_geom->stripe_offset = 0;
}
static void map_blocks_raid56_read(struct btrfs_chunk_map *map,
struct btrfs_io_geometry *io_geom)
{
int data_stripes = nr_data_stripes(map);
ASSERT(io_geom->mirror_num <= 1);
/* Just grab the data stripe directly. */
io_geom->stripe_index = io_geom->stripe_nr % data_stripes;
io_geom->stripe_nr /= data_stripes;
/* We distribute the parity blocks across stripes. */
io_geom->stripe_index =
(io_geom->stripe_nr + io_geom->stripe_index) % map->num_stripes;
if (io_geom->op == BTRFS_MAP_READ && io_geom->mirror_num < 1)
io_geom->mirror_num = 1;
}
static void map_blocks_single(const struct btrfs_chunk_map *map,
struct btrfs_io_geometry *io_geom)
{
io_geom->stripe_index = io_geom->stripe_nr % map->num_stripes;
io_geom->stripe_nr /= map->num_stripes;
io_geom->mirror_num = io_geom->stripe_index + 1;
}
/*
* Map one logical range to one or more physical ranges.
*
* @length: (Mandatory) mapped length of this run.
* One logical range can be split into different segments
* due to factors like zones and RAID0/5/6/10 stripe
* boundaries.
*
* @bioc_ret: (Mandatory) returned btrfs_io_context structure.
* which has one or more physical ranges (btrfs_io_stripe)
* recorded inside.
* Caller should call btrfs_put_bioc() to free it after use.
*
* @smap: (Optional) single physical range optimization.
* If the map request can be fulfilled by one single
* physical range, and this is parameter is not NULL,
* then @bioc_ret would be NULL, and @smap would be
* updated.
*
* @mirror_num_ret: (Mandatory) returned mirror number if the original
* value is 0.
*
* Mirror number 0 means to choose any live mirrors.
*
* For non-RAID56 profiles, non-zero mirror_num means
* the Nth mirror. (e.g. mirror_num 1 means the first
* copy).
*
* For RAID56 profile, mirror 1 means rebuild from P and
* the remaining data stripes.
*
* For RAID6 profile, mirror > 2 means mark another
* data/P stripe error and rebuild from the remaining
* stripes..
*/
int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
u64 logical, u64 *length,
struct btrfs_io_context **bioc_ret,
struct btrfs_io_stripe *smap, int *mirror_num_ret)
{
struct btrfs_chunk_map *map;
struct btrfs_io_geometry io_geom = { 0 };
u64 map_offset;
int ret = 0;
int num_copies;
struct btrfs_io_context *bioc = NULL;
struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
int dev_replace_is_ongoing = 0;
u16 num_alloc_stripes;
u64 max_len;
ASSERT(bioc_ret);
io_geom.mirror_num = (mirror_num_ret ? *mirror_num_ret : 0);
io_geom.num_stripes = 1;
io_geom.stripe_index = 0;
io_geom.op = op;
map = btrfs_get_chunk_map(fs_info, logical, *length);
if (IS_ERR(map))
return PTR_ERR(map);
num_copies = btrfs_chunk_map_num_copies(map);
if (io_geom.mirror_num > num_copies)
return -EINVAL;
map_offset = logical - map->start;
io_geom.raid56_full_stripe_start = (u64)-1;
max_len = btrfs_max_io_len(map, map_offset, &io_geom);
*length = min_t(u64, map->chunk_len - map_offset, max_len);
if (dev_replace->replace_task != current)
down_read(&dev_replace->rwsem);
dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);
/*
* Hold the semaphore for read during the whole operation, write is
* requested at commit time but must wait.
*/
if (!dev_replace_is_ongoing && dev_replace->replace_task != current)
up_read(&dev_replace->rwsem);
switch (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
case BTRFS_BLOCK_GROUP_RAID0:
map_blocks_raid0(map, &io_geom);
break;
case BTRFS_BLOCK_GROUP_RAID1:
case BTRFS_BLOCK_GROUP_RAID1C3:
case BTRFS_BLOCK_GROUP_RAID1C4:
map_blocks_raid1(fs_info, map, &io_geom, dev_replace_is_ongoing);
break;
case BTRFS_BLOCK_GROUP_DUP:
map_blocks_dup(map, &io_geom);
break;
case BTRFS_BLOCK_GROUP_RAID10:
map_blocks_raid10(fs_info, map, &io_geom, dev_replace_is_ongoing);
break;
case BTRFS_BLOCK_GROUP_RAID5:
case BTRFS_BLOCK_GROUP_RAID6:
if (op != BTRFS_MAP_READ || io_geom.mirror_num > 1)
map_blocks_raid56_write(map, &io_geom, logical, length);
else
map_blocks_raid56_read(map, &io_geom);
break;
default:
/*
* After this, stripe_nr is the number of stripes on this
* device we have to walk to find the data, and stripe_index is
* the number of our device in the stripe array
*/
map_blocks_single(map, &io_geom);
break;
}
if (io_geom.stripe_index >= map->num_stripes) {
btrfs_crit(fs_info,
"stripe index math went horribly wrong, got stripe_index=%u, num_stripes=%u",
io_geom.stripe_index, map->num_stripes);
ret = -EINVAL;
goto out;
}
num_alloc_stripes = io_geom.num_stripes;
if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL &&
op != BTRFS_MAP_READ)
/*
* For replace case, we need to add extra stripes for extra
* duplicated stripes.
*
* For both WRITE and GET_READ_MIRRORS, we may have at most
* 2 more stripes (DUP types, otherwise 1).
*/
num_alloc_stripes += 2;
/*
* If this I/O maps to a single device, try to return the device and
* physical block information on the stack instead of allocating an
* I/O context structure.
*/
if (is_single_device_io(fs_info, smap, map, num_alloc_stripes, op,
io_geom.mirror_num)) {
ret = set_io_stripe(fs_info, logical, length, smap, map, &io_geom);
if (mirror_num_ret)
*mirror_num_ret = io_geom.mirror_num;
*bioc_ret = NULL;
goto out;
}
bioc = alloc_btrfs_io_context(fs_info, logical, num_alloc_stripes);
if (!bioc) {
ret = -ENOMEM;
goto out;
}
bioc->map_type = map->type;
/*
* For RAID56 full map, we need to make sure the stripes[] follows the
* rule that data stripes are all ordered, then followed with P and Q
* (if we have).
*
* It's still mostly the same as other profiles, just with extra rotation.
*/
if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK &&
(op != BTRFS_MAP_READ || io_geom.mirror_num > 1)) {
/*
* For RAID56 @stripe_nr is already the number of full stripes
* before us, which is also the rotation value (needs to modulo
* with num_stripes).
*
* In this case, we just add @stripe_nr with @i, then do the
* modulo, to reduce one modulo call.
*/
bioc->full_stripe_logical = map->start +
btrfs_stripe_nr_to_offset(io_geom.stripe_nr *
nr_data_stripes(map));
for (int i = 0; i < io_geom.num_stripes; i++) {
struct btrfs_io_stripe *dst = &bioc->stripes[i];
u32 stripe_index;
stripe_index = (i + io_geom.stripe_nr) % io_geom.num_stripes;
dst->dev = map->stripes[stripe_index].dev;
dst->physical =
map->stripes[stripe_index].physical +
io_geom.stripe_offset +
btrfs_stripe_nr_to_offset(io_geom.stripe_nr);
}
} else {
/*
* For all other non-RAID56 profiles, just copy the target
* stripe into the bioc.
*/
for (int i = 0; i < io_geom.num_stripes; i++) {
ret = set_io_stripe(fs_info, logical, length,
&bioc->stripes[i], map, &io_geom);
if (ret < 0)
break;
io_geom.stripe_index++;
}
}
if (ret) {
*bioc_ret = NULL;
btrfs_put_bioc(bioc);
goto out;
}
if (op != BTRFS_MAP_READ)
io_geom.max_errors = btrfs_chunk_max_errors(map);
if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL &&
op != BTRFS_MAP_READ) {
handle_ops_on_dev_replace(bioc, dev_replace, logical, &io_geom);
}
*bioc_ret = bioc;
bioc->num_stripes = io_geom.num_stripes;
bioc->max_errors = io_geom.max_errors;
bioc->mirror_num = io_geom.mirror_num;
out:
if (dev_replace_is_ongoing && dev_replace->replace_task != current) {
lockdep_assert_held(&dev_replace->rwsem);
/* Unlock and let waiting writers proceed */
up_read(&dev_replace->rwsem);
}
btrfs_free_chunk_map(map);
return ret;
}
static bool dev_args_match_fs_devices(const struct btrfs_dev_lookup_args *args,
const struct btrfs_fs_devices *fs_devices)
{
if (args->fsid == NULL)
return true;
if (memcmp(fs_devices->metadata_uuid, args->fsid, BTRFS_FSID_SIZE) == 0)
return true;
return false;
}
static bool dev_args_match_device(const struct btrfs_dev_lookup_args *args,
const struct btrfs_device *device)
{
if (args->missing) {
if (test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state) &&
!device->bdev)
return true;
return false;
}
if (device->devid != args->devid)
return false;
if (args->uuid && memcmp(device->uuid, args->uuid, BTRFS_UUID_SIZE) != 0)
return false;
return true;
}
/*
* Find a device specified by @devid or @uuid in the list of @fs_devices, or
* return NULL.
*
* If devid and uuid are both specified, the match must be exact, otherwise
* only devid is used.
*/
struct btrfs_device *btrfs_find_device(const struct btrfs_fs_devices *fs_devices,
const struct btrfs_dev_lookup_args *args)
{
struct btrfs_device *device;
struct btrfs_fs_devices *seed_devs;
if (dev_args_match_fs_devices(args, fs_devices)) {
list_for_each_entry(device, &fs_devices->devices, dev_list) {
if (dev_args_match_device(args, device))
return device;
}
}
list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) {
if (!dev_args_match_fs_devices(args, seed_devs))
continue;
list_for_each_entry(device, &seed_devs->devices, dev_list) {
if (dev_args_match_device(args, device))
return device;
}
}
return NULL;
}
static struct btrfs_device *add_missing_dev(struct btrfs_fs_devices *fs_devices,
u64 devid, u8 *dev_uuid)
{
struct btrfs_device *device;
unsigned int nofs_flag;
/*
* We call this under the chunk_mutex, so we want to use NOFS for this
* allocation, however we don't want to change btrfs_alloc_device() to
* always do NOFS because we use it in a lot of other GFP_KERNEL safe
* places.
*/
nofs_flag = memalloc_nofs_save();
device = btrfs_alloc_device(NULL, &devid, dev_uuid, NULL);
memalloc_nofs_restore(nofs_flag);
if (IS_ERR(device))
return device;
list_add(&device->dev_list, &fs_devices->devices);
device->fs_devices = fs_devices;
fs_devices->num_devices++;
set_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
fs_devices->missing_devices++;
return device;
}
/*
* Allocate new device struct, set up devid and UUID.
*
* @fs_info: used only for generating a new devid, can be NULL if
* devid is provided (i.e. @devid != NULL).
* @devid: a pointer to devid for this device. If NULL a new devid
* is generated.
* @uuid: a pointer to UUID for this device. If NULL a new UUID
* is generated.
* @path: a pointer to device path if available, NULL otherwise.
*
* Return: a pointer to a new &struct btrfs_device on success; ERR_PTR()
* on error. Returned struct is not linked onto any lists and must be
* destroyed with btrfs_free_device.
*/
struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
const u64 *devid, const u8 *uuid,
const char *path)
{
struct btrfs_device *dev;
u64 tmp;
if (WARN_ON(!devid && !fs_info))
return ERR_PTR(-EINVAL);
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return ERR_PTR(-ENOMEM);
INIT_LIST_HEAD(&dev->dev_list);
INIT_LIST_HEAD(&dev->dev_alloc_list);
INIT_LIST_HEAD(&dev->post_commit_list);
atomic_set(&dev->dev_stats_ccnt, 0);
btrfs_device_data_ordered_init(dev);
extent_io_tree_init(fs_info, &dev->alloc_state, IO_TREE_DEVICE_ALLOC_STATE);
if (devid)
tmp = *devid;
else {
int ret;
ret = find_next_devid(fs_info, &tmp);
if (ret) {
btrfs_free_device(dev);
return ERR_PTR(ret);
}
}
dev->devid = tmp;
if (uuid)
memcpy(dev->uuid, uuid, BTRFS_UUID_SIZE);
else
generate_random_uuid(dev->uuid);
if (path) {
struct rcu_string *name;
name = rcu_string_strdup(path, GFP_KERNEL);
if (!name) {
btrfs_free_device(dev);
return ERR_PTR(-ENOMEM);
}
rcu_assign_pointer(dev->name, name);
}
return dev;
}
static void btrfs_report_missing_device(struct btrfs_fs_info *fs_info,
u64 devid, u8 *uuid, bool error)
{
if (error)
btrfs_err_rl(fs_info, "devid %llu uuid %pU is missing",
devid, uuid);
else
btrfs_warn_rl(fs_info, "devid %llu uuid %pU is missing",
devid, uuid);
}
u64 btrfs_calc_stripe_length(const struct btrfs_chunk_map *map)
{
const int data_stripes = calc_data_stripes(map->type, map->num_stripes);
return div_u64(map->chunk_len, data_stripes);
}
#if BITS_PER_LONG == 32
/*
* Due to page cache limit, metadata beyond BTRFS_32BIT_MAX_FILE_SIZE
* can't be accessed on 32bit systems.
*
* This function do mount time check to reject the fs if it already has
* metadata chunk beyond that limit.
*/
static int check_32bit_meta_chunk(struct btrfs_fs_info *fs_info,
u64 logical, u64 length, u64 type)
{
if (!(type & BTRFS_BLOCK_GROUP_METADATA))
return 0;
if (logical + length < MAX_LFS_FILESIZE)
return 0;
btrfs_err_32bit_limit(fs_info);
return -EOVERFLOW;
}
/*
* This is to give early warning for any metadata chunk reaching
* BTRFS_32BIT_EARLY_WARN_THRESHOLD.
* Although we can still access the metadata, it's not going to be possible
* once the limit is reached.
*/
static void warn_32bit_meta_chunk(struct btrfs_fs_info *fs_info,
u64 logical, u64 length, u64 type)
{
if (!(type & BTRFS_BLOCK_GROUP_METADATA))
return;
if (logical + length < BTRFS_32BIT_EARLY_WARN_THRESHOLD)
return;
btrfs_warn_32bit_limit(fs_info);
}
#endif
static struct btrfs_device *handle_missing_device(struct btrfs_fs_info *fs_info,
u64 devid, u8 *uuid)
{
struct btrfs_device *dev;
if (!btrfs_test_opt(fs_info, DEGRADED)) {
btrfs_report_missing_device(fs_info, devid, uuid, true);
return ERR_PTR(-ENOENT);
}
dev = add_missing_dev(fs_info->fs_devices, devid, uuid);
if (IS_ERR(dev)) {
btrfs_err(fs_info, "failed to init missing device %llu: %ld",
devid, PTR_ERR(dev));
return dev;
}
btrfs_report_missing_device(fs_info, devid, uuid, false);
return dev;
}
static int read_one_chunk(struct btrfs_key *key, struct extent_buffer *leaf,
struct btrfs_chunk *chunk)
{
BTRFS_DEV_LOOKUP_ARGS(args);
struct btrfs_fs_info *fs_info = leaf->fs_info;
struct btrfs_chunk_map *map;
u64 logical;
u64 length;
u64 devid;
u64 type;
u8 uuid[BTRFS_UUID_SIZE];
int index;
int num_stripes;
int ret;
int i;
logical = key->offset;
length = btrfs_chunk_length(leaf, chunk);
type = btrfs_chunk_type(leaf, chunk);
index = btrfs_bg_flags_to_raid_index(type);
num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
#if BITS_PER_LONG == 32
ret = check_32bit_meta_chunk(fs_info, logical, length, type);
if (ret < 0)
return ret;
warn_32bit_meta_chunk(fs_info, logical, length, type);
#endif
/*
* Only need to verify chunk item if we're reading from sys chunk array,
* as chunk item in tree block is already verified by tree-checker.
*/
if (leaf->start == BTRFS_SUPER_INFO_OFFSET) {
ret = btrfs_check_chunk_valid(leaf, chunk, logical);
if (ret)
return ret;
}
map = btrfs_find_chunk_map(fs_info, logical, 1);
/* already mapped? */
if (map && map->start <= logical && map->start + map->chunk_len > logical) {
btrfs_free_chunk_map(map);
return 0;
} else if (map) {
btrfs_free_chunk_map(map);
}
map = btrfs_alloc_chunk_map(num_stripes, GFP_NOFS);
if (!map)
return -ENOMEM;
map->start = logical;
map->chunk_len = length;
map->num_stripes = num_stripes;
map->io_width = btrfs_chunk_io_width(leaf, chunk);
map->io_align = btrfs_chunk_io_align(leaf, chunk);
map->type = type;
/*
* We can't use the sub_stripes value, as for profiles other than
* RAID10, they may have 0 as sub_stripes for filesystems created by
* older mkfs (<v5.4).
* In that case, it can cause divide-by-zero errors later.
* Since currently sub_stripes is fixed for each profile, let's
* use the trusted value instead.
*/
map->sub_stripes = btrfs_raid_array[index].sub_stripes;
map->verified_stripes = 0;
map->stripe_size = btrfs_calc_stripe_length(map);
for (i = 0; i < num_stripes; i++) {
map->stripes[i].physical =
btrfs_stripe_offset_nr(leaf, chunk, i);
devid = btrfs_stripe_devid_nr(leaf, chunk, i);
args.devid = devid;
read_extent_buffer(leaf, uuid, (unsigned long)
btrfs_stripe_dev_uuid_nr(chunk, i),
BTRFS_UUID_SIZE);
args.uuid = uuid;
map->stripes[i].dev = btrfs_find_device(fs_info->fs_devices, &args);
if (!map->stripes[i].dev) {
map->stripes[i].dev = handle_missing_device(fs_info,
devid, uuid);
if (IS_ERR(map->stripes[i].dev)) {
ret = PTR_ERR(map->stripes[i].dev);
btrfs_free_chunk_map(map);
return ret;
}
}
set_bit(BTRFS_DEV_STATE_IN_FS_METADATA,
&(map->stripes[i].dev->dev_state));
}
ret = btrfs_add_chunk_map(fs_info, map);
if (ret < 0) {
btrfs_err(fs_info,
"failed to add chunk map, start=%llu len=%llu: %d",
map->start, map->chunk_len, ret);
}
return ret;
}
static void fill_device_from_item(struct extent_buffer *leaf,
struct btrfs_dev_item *dev_item,
struct btrfs_device *device)
{
unsigned long ptr;
device->devid = btrfs_device_id(leaf, dev_item);
device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
device->total_bytes = device->disk_total_bytes;
device->commit_total_bytes = device->disk_total_bytes;
device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
device->commit_bytes_used = device->bytes_used;
device->type = btrfs_device_type(leaf, dev_item);
device->io_align = btrfs_device_io_align(leaf, dev_item);
device->io_width = btrfs_device_io_width(leaf, dev_item);
device->sector_size = btrfs_device_sector_size(leaf, dev_item);
WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID);
clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
ptr = btrfs_device_uuid(dev_item);
read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
}
static struct btrfs_fs_devices *open_seed_devices(struct btrfs_fs_info *fs_info,
u8 *fsid)
{
struct btrfs_fs_devices *fs_devices;
int ret;
lockdep_assert_held(&uuid_mutex);
ASSERT(fsid);
/* This will match only for multi-device seed fs */
list_for_each_entry(fs_devices, &fs_info->fs_devices->seed_list, seed_list)
if (!memcmp(fs_devices->fsid, fsid, BTRFS_FSID_SIZE))
return fs_devices;
fs_devices = find_fsid(fsid, NULL);
if (!fs_devices) {
if (!btrfs_test_opt(fs_info, DEGRADED))
return ERR_PTR(-ENOENT);
fs_devices = alloc_fs_devices(fsid);
if (IS_ERR(fs_devices))
return fs_devices;
fs_devices->seeding = true;
fs_devices->opened = 1;
return fs_devices;
}
/*
* Upon first call for a seed fs fsid, just create a private copy of the
* respective fs_devices and anchor it at fs_info->fs_devices->seed_list
*/
fs_devices = clone_fs_devices(fs_devices);
if (IS_ERR(fs_devices))
return fs_devices;
ret = open_fs_devices(fs_devices, BLK_OPEN_READ, fs_info->bdev_holder);
if (ret) {
free_fs_devices(fs_devices);
return ERR_PTR(ret);
}
if (!fs_devices->seeding) {
close_fs_devices(fs_devices);
free_fs_devices(fs_devices);
return ERR_PTR(-EINVAL);
}
list_add(&fs_devices->seed_list, &fs_info->fs_devices->seed_list);
return fs_devices;
}
static int read_one_dev(struct extent_buffer *leaf,
struct btrfs_dev_item *dev_item)
{
BTRFS_DEV_LOOKUP_ARGS(args);
struct btrfs_fs_info *fs_info = leaf->fs_info;
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
struct btrfs_device *device;
u64 devid;
int ret;
u8 fs_uuid[BTRFS_FSID_SIZE];
u8 dev_uuid[BTRFS_UUID_SIZE];
devid = btrfs_device_id(leaf, dev_item);
args.devid = devid;
read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
BTRFS_UUID_SIZE);
read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
BTRFS_FSID_SIZE);
args.uuid = dev_uuid;
args.fsid = fs_uuid;
if (memcmp(fs_uuid, fs_devices->metadata_uuid, BTRFS_FSID_SIZE)) {
fs_devices = open_seed_devices(fs_info, fs_uuid);
if (IS_ERR(fs_devices))
return PTR_ERR(fs_devices);
}
device = btrfs_find_device(fs_info->fs_devices, &args);
if (!device) {
if (!btrfs_test_opt(fs_info, DEGRADED)) {
btrfs_report_missing_device(fs_info, devid,
dev_uuid, true);
return -ENOENT;
}
device = add_missing_dev(fs_devices, devid, dev_uuid);
if (IS_ERR(device)) {
btrfs_err(fs_info,
"failed to add missing dev %llu: %ld",
devid, PTR_ERR(device));
return PTR_ERR(device);
}
btrfs_report_missing_device(fs_info, devid, dev_uuid, false);
} else {
if (!device->bdev) {
if (!btrfs_test_opt(fs_info, DEGRADED)) {
btrfs_report_missing_device(fs_info,
devid, dev_uuid, true);
return -ENOENT;
}
btrfs_report_missing_device(fs_info, devid,
dev_uuid, false);
}
if (!device->bdev &&
!test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) {
/*
* this happens when a device that was properly setup
* in the device info lists suddenly goes bad.
* device->bdev is NULL, and so we have to set
* device->missing to one here
*/
device->fs_devices->missing_devices++;
set_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
}
/* Move the device to its own fs_devices */
if (device->fs_devices != fs_devices) {
ASSERT(test_bit(BTRFS_DEV_STATE_MISSING,
&device->dev_state));
list_move(&device->dev_list, &fs_devices->devices);
device->fs_devices->num_devices--;
fs_devices->num_devices++;
device->fs_devices->missing_devices--;
fs_devices->missing_devices++;
device->fs_devices = fs_devices;
}
}
if (device->fs_devices != fs_info->fs_devices) {
BUG_ON(test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state));
if (device->generation !=
btrfs_device_generation(leaf, dev_item))
return -EINVAL;
}
fill_device_from_item(leaf, dev_item, device);
if (device->bdev) {
u64 max_total_bytes = bdev_nr_bytes(device->bdev);
if (device->total_bytes > max_total_bytes) {
btrfs_err(fs_info,
"device total_bytes should be at most %llu but found %llu",
max_total_bytes, device->total_bytes);
return -EINVAL;
}
}
set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
device->fs_devices->total_rw_bytes += device->total_bytes;
atomic64_add(device->total_bytes - device->bytes_used,
&fs_info->free_chunk_space);
}
ret = 0;
return ret;
}
int btrfs_read_sys_array(struct btrfs_fs_info *fs_info)
{
struct btrfs_super_block *super_copy = fs_info->super_copy;
struct extent_buffer *sb;
struct btrfs_disk_key *disk_key;
struct btrfs_chunk *chunk;
u8 *array_ptr;
unsigned long sb_array_offset;
int ret = 0;
u32 num_stripes;
u32 array_size;
u32 len = 0;
u32 cur_offset;
u64 type;
struct btrfs_key key;
ASSERT(BTRFS_SUPER_INFO_SIZE <= fs_info->nodesize);
/*
* We allocated a dummy extent, just to use extent buffer accessors.
* There will be unused space after BTRFS_SUPER_INFO_SIZE, but
* that's fine, we will not go beyond system chunk array anyway.
*/
sb = alloc_dummy_extent_buffer(fs_info, BTRFS_SUPER_INFO_OFFSET);
if (!sb)
return -ENOMEM;
set_extent_buffer_uptodate(sb);
write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
array_size = btrfs_super_sys_array_size(super_copy);
array_ptr = super_copy->sys_chunk_array;
sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array);
cur_offset = 0;
while (cur_offset < array_size) {
disk_key = (struct btrfs_disk_key *)array_ptr;
len = sizeof(*disk_key);
if (cur_offset + len > array_size)
goto out_short_read;
btrfs_disk_key_to_cpu(&key, disk_key);
array_ptr += len;
sb_array_offset += len;
cur_offset += len;
if (key.type != BTRFS_CHUNK_ITEM_KEY) {
btrfs_err(fs_info,
"unexpected item type %u in sys_array at offset %u",
(u32)key.type, cur_offset);
ret = -EIO;
break;
}
chunk = (struct btrfs_chunk *)sb_array_offset;
/*
* At least one btrfs_chunk with one stripe must be present,
* exact stripe count check comes afterwards
*/
len = btrfs_chunk_item_size(1);
if (cur_offset + len > array_size)
goto out_short_read;
num_stripes = btrfs_chunk_num_stripes(sb, chunk);
if (!num_stripes) {
btrfs_err(fs_info,
"invalid number of stripes %u in sys_array at offset %u",
num_stripes, cur_offset);
ret = -EIO;
break;
}
type = btrfs_chunk_type(sb, chunk);
if ((type & BTRFS_BLOCK_GROUP_SYSTEM) == 0) {
btrfs_err(fs_info,
"invalid chunk type %llu in sys_array at offset %u",
type, cur_offset);
ret = -EIO;
break;
}
len = btrfs_chunk_item_size(num_stripes);
if (cur_offset + len > array_size)
goto out_short_read;
ret = read_one_chunk(&key, sb, chunk);
if (ret)
break;
array_ptr += len;
sb_array_offset += len;
cur_offset += len;
}
clear_extent_buffer_uptodate(sb);
free_extent_buffer_stale(sb);
return ret;
out_short_read:
btrfs_err(fs_info, "sys_array too short to read %u bytes at offset %u",
len, cur_offset);
clear_extent_buffer_uptodate(sb);
free_extent_buffer_stale(sb);
return -EIO;
}
/*
* Check if all chunks in the fs are OK for read-write degraded mount
*
* If the @failing_dev is specified, it's accounted as missing.
*
* Return true if all chunks meet the minimal RW mount requirements.
* Return false if any chunk doesn't meet the minimal RW mount requirements.
*/
bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
struct btrfs_device *failing_dev)
{
struct btrfs_chunk_map *map;
u64 next_start;
bool ret = true;
map = btrfs_find_chunk_map(fs_info, 0, U64_MAX);
/* No chunk at all? Return false anyway */
if (!map) {
ret = false;
goto out;
}
while (map) {
int missing = 0;
int max_tolerated;
int i;
max_tolerated =
btrfs_get_num_tolerated_disk_barrier_failures(
map->type);
for (i = 0; i < map->num_stripes; i++) {
struct btrfs_device *dev = map->stripes[i].dev;
if (!dev || !dev->bdev ||
test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state) ||
dev->last_flush_error)
missing++;
else if (failing_dev && failing_dev == dev)
missing++;
}
if (missing > max_tolerated) {
if (!failing_dev)
btrfs_warn(fs_info,
"chunk %llu missing %d devices, max tolerance is %d for writable mount",
map->start, missing, max_tolerated);
btrfs_free_chunk_map(map);
ret = false;
goto out;
}
next_start = map->start + map->chunk_len;
btrfs_free_chunk_map(map);
map = btrfs_find_chunk_map(fs_info, next_start, U64_MAX - next_start);
}
out:
return ret;
}
static void readahead_tree_node_children(struct extent_buffer *node)
{
int i;
const int nr_items = btrfs_header_nritems(node);
for (i = 0; i < nr_items; i++)
btrfs_readahead_node_child(node, i);
}
int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info)
{
struct btrfs_root *root = fs_info->chunk_root;
struct btrfs_path *path;
struct extent_buffer *leaf;
struct btrfs_key key;
struct btrfs_key found_key;
int ret;
int slot;
int iter_ret = 0;
u64 total_dev = 0;
u64 last_ra_node = 0;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
/*
* uuid_mutex is needed only if we are mounting a sprout FS
* otherwise we don't need it.
*/
mutex_lock(&uuid_mutex);
/*
* It is possible for mount and umount to race in such a way that
* we execute this code path, but open_fs_devices failed to clear
* total_rw_bytes. We certainly want it cleared before reading the
* device items, so clear it here.
*/
fs_info->fs_devices->total_rw_bytes = 0;
/*
* Lockdep complains about possible circular locking dependency between
* a disk's open_mutex (struct gendisk.open_mutex), the rw semaphores
* used for freeze procection of a fs (struct super_block.s_writers),
* which we take when starting a transaction, and extent buffers of the
* chunk tree if we call read_one_dev() while holding a lock on an
* extent buffer of the chunk tree. Since we are mounting the filesystem
* and at this point there can't be any concurrent task modifying the
* chunk tree, to keep it simple, just skip locking on the chunk tree.
*/
ASSERT(!test_bit(BTRFS_FS_OPEN, &fs_info->flags));
path->skip_locking = 1;
/*
* Read all device items, and then all the chunk items. All
* device items are found before any chunk item (their object id
* is smaller than the lowest possible object id for a chunk
* item - BTRFS_FIRST_CHUNK_TREE_OBJECTID).
*/
key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
key.offset = 0;
key.type = 0;
btrfs_for_each_slot(root, &key, &found_key, path, iter_ret) {
struct extent_buffer *node = path->nodes[1];
leaf = path->nodes[0];
slot = path->slots[0];
if (node) {
if (last_ra_node != node->start) {
readahead_tree_node_children(node);
last_ra_node = node->start;
}
}
if (found_key.type == BTRFS_DEV_ITEM_KEY) {
struct btrfs_dev_item *dev_item;
dev_item = btrfs_item_ptr(leaf, slot,
struct btrfs_dev_item);
ret = read_one_dev(leaf, dev_item);
if (ret)
goto error;
total_dev++;
} else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
struct btrfs_chunk *chunk;
/*
* We are only called at mount time, so no need to take
* fs_info->chunk_mutex. Plus, to avoid lockdep warnings,
* we always lock first fs_info->chunk_mutex before
* acquiring any locks on the chunk tree. This is a
* requirement for chunk allocation, see the comment on
* top of btrfs_chunk_alloc() for details.
*/
chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
ret = read_one_chunk(&found_key, leaf, chunk);
if (ret)
goto error;
}
}
/* Catch error found during iteration */
if (iter_ret < 0) {
ret = iter_ret;
goto error;
}
/*
* After loading chunk tree, we've got all device information,
* do another round of validation checks.
*/
if (total_dev != fs_info->fs_devices->total_devices) {
btrfs_warn(fs_info,
"super block num_devices %llu mismatch with DEV_ITEM count %llu, will be repaired on next transaction commit",
btrfs_super_num_devices(fs_info->super_copy),
total_dev);
fs_info->fs_devices->total_devices = total_dev;
btrfs_set_super_num_devices(fs_info->super_copy, total_dev);
}
if (btrfs_super_total_bytes(fs_info->super_copy) <
fs_info->fs_devices->total_rw_bytes) {
btrfs_err(fs_info,
"super_total_bytes %llu mismatch with fs_devices total_rw_bytes %llu",
btrfs_super_total_bytes(fs_info->super_copy),
fs_info->fs_devices->total_rw_bytes);
ret = -EINVAL;
goto error;
}
ret = 0;
error:
mutex_unlock(&uuid_mutex);
btrfs_free_path(path);
return ret;
}
int btrfs_init_devices_late(struct btrfs_fs_info *fs_info)
{
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
struct btrfs_device *device;
int ret = 0;
fs_devices->fs_info = fs_info;
mutex_lock(&fs_devices->device_list_mutex);
list_for_each_entry(device, &fs_devices->devices, dev_list)
device->fs_info = fs_info;
list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) {
list_for_each_entry(device, &seed_devs->devices, dev_list) {
device->fs_info = fs_info;
ret = btrfs_get_dev_zone_info(device, false);
if (ret)
break;
}
seed_devs->fs_info = fs_info;
}
mutex_unlock(&fs_devices->device_list_mutex);
return ret;
}
static u64 btrfs_dev_stats_value(const struct extent_buffer *eb,
const struct btrfs_dev_stats_item *ptr,
int index)
{
u64 val;
read_extent_buffer(eb, &val,
offsetof(struct btrfs_dev_stats_item, values) +
((unsigned long)ptr) + (index * sizeof(u64)),
sizeof(val));
return val;
}
static void btrfs_set_dev_stats_value(struct extent_buffer *eb,
struct btrfs_dev_stats_item *ptr,
int index, u64 val)
{
write_extent_buffer(eb, &val,
offsetof(struct btrfs_dev_stats_item, values) +
((unsigned long)ptr) + (index * sizeof(u64)),
sizeof(val));
}
static int btrfs_device_init_dev_stats(struct btrfs_device *device,
struct btrfs_path *path)
{
struct btrfs_dev_stats_item *ptr;
struct extent_buffer *eb;
struct btrfs_key key;
int item_size;
int i, ret, slot;
if (!device->fs_info->dev_root)
return 0;
key.objectid = BTRFS_DEV_STATS_OBJECTID;
key.type = BTRFS_PERSISTENT_ITEM_KEY;
key.offset = device->devid;
ret = btrfs_search_slot(NULL, device->fs_info->dev_root, &key, path, 0, 0);
if (ret) {
for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
btrfs_dev_stat_set(device, i, 0);
device->dev_stats_valid = 1;
btrfs_release_path(path);
return ret < 0 ? ret : 0;
}
slot = path->slots[0];
eb = path->nodes[0];
item_size = btrfs_item_size(eb, slot);
ptr = btrfs_item_ptr(eb, slot, struct btrfs_dev_stats_item);
for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
if (item_size >= (1 + i) * sizeof(__le64))
btrfs_dev_stat_set(device, i,
btrfs_dev_stats_value(eb, ptr, i));
else
btrfs_dev_stat_set(device, i, 0);
}
device->dev_stats_valid = 1;
btrfs_dev_stat_print_on_load(device);
btrfs_release_path(path);
return 0;
}
int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info)
{
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
struct btrfs_device *device;
struct btrfs_path *path = NULL;
int ret = 0;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
mutex_lock(&fs_devices->device_list_mutex);
list_for_each_entry(device, &fs_devices->devices, dev_list) {
ret = btrfs_device_init_dev_stats(device, path);
if (ret)
goto out;
}
list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) {
list_for_each_entry(device, &seed_devs->devices, dev_list) {
ret = btrfs_device_init_dev_stats(device, path);
if (ret)
goto out;
}
}
out:
mutex_unlock(&fs_devices->device_list_mutex);
btrfs_free_path(path);
return ret;
}
static int update_dev_stat_item(struct btrfs_trans_handle *trans,
struct btrfs_device *device)
{
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_root *dev_root = fs_info->dev_root;
struct btrfs_path *path;
struct btrfs_key key;
struct extent_buffer *eb;
struct btrfs_dev_stats_item *ptr;
int ret;
int i;
key.objectid = BTRFS_DEV_STATS_OBJECTID;
key.type = BTRFS_PERSISTENT_ITEM_KEY;
key.offset = device->devid;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
if (ret < 0) {
btrfs_warn_in_rcu(fs_info,
"error %d while searching for dev_stats item for device %s",
ret, btrfs_dev_name(device));
goto out;
}
if (ret == 0 &&
btrfs_item_size(path->nodes[0], path->slots[0]) < sizeof(*ptr)) {
/* need to delete old one and insert a new one */
ret = btrfs_del_item(trans, dev_root, path);
if (ret != 0) {
btrfs_warn_in_rcu(fs_info,
"delete too small dev_stats item for device %s failed %d",
btrfs_dev_name(device), ret);
goto out;
}
ret = 1;
}
if (ret == 1) {
/* need to insert a new item */
btrfs_release_path(path);
ret = btrfs_insert_empty_item(trans, dev_root, path,
&key, sizeof(*ptr));
if (ret < 0) {
btrfs_warn_in_rcu(fs_info,
"insert dev_stats item for device %s failed %d",
btrfs_dev_name(device), ret);
goto out;
}
}
eb = path->nodes[0];
ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item);
for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
btrfs_set_dev_stats_value(eb, ptr, i,
btrfs_dev_stat_read(device, i));
btrfs_mark_buffer_dirty(trans, eb);
out:
btrfs_free_path(path);
return ret;
}
/*
* called from commit_transaction. Writes all changed device stats to disk.
*/
int btrfs_run_dev_stats(struct btrfs_trans_handle *trans)
{
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
struct btrfs_device *device;
int stats_cnt;
int ret = 0;
mutex_lock(&fs_devices->device_list_mutex);
list_for_each_entry(device, &fs_devices->devices, dev_list) {
stats_cnt = atomic_read(&device->dev_stats_ccnt);
if (!device->dev_stats_valid || stats_cnt == 0)
continue;
/*
* There is a LOAD-LOAD control dependency between the value of
* dev_stats_ccnt and updating the on-disk values which requires
* reading the in-memory counters. Such control dependencies
* require explicit read memory barriers.
*
* This memory barriers pairs with smp_mb__before_atomic in
* btrfs_dev_stat_inc/btrfs_dev_stat_set and with the full
* barrier implied by atomic_xchg in
* btrfs_dev_stats_read_and_reset
*/
smp_rmb();
ret = update_dev_stat_item(trans, device);
if (!ret)
atomic_sub(stats_cnt, &device->dev_stats_ccnt);
}
mutex_unlock(&fs_devices->device_list_mutex);
return ret;
}
void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index)
{
btrfs_dev_stat_inc(dev, index);
if (!dev->dev_stats_valid)
return;
btrfs_err_rl_in_rcu(dev->fs_info,
"bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u",
btrfs_dev_name(dev),
btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
}
static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
{
int i;
for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
if (btrfs_dev_stat_read(dev, i) != 0)
break;
if (i == BTRFS_DEV_STAT_VALUES_MAX)
return; /* all values == 0, suppress message */
btrfs_info_in_rcu(dev->fs_info,
"bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u",
btrfs_dev_name(dev),
btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
}
int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
struct btrfs_ioctl_get_dev_stats *stats)
{
BTRFS_DEV_LOOKUP_ARGS(args);
struct btrfs_device *dev;
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
int i;
mutex_lock(&fs_devices->device_list_mutex);
args.devid = stats->devid;
dev = btrfs_find_device(fs_info->fs_devices, &args);
mutex_unlock(&fs_devices->device_list_mutex);
if (!dev) {
btrfs_warn(fs_info, "get dev_stats failed, device not found");
return -ENODEV;
} else if (!dev->dev_stats_valid) {
btrfs_warn(fs_info, "get dev_stats failed, not yet valid");
return -ENODEV;
} else if (stats->flags & BTRFS_DEV_STATS_RESET) {
for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
if (stats->nr_items > i)
stats->values[i] =
btrfs_dev_stat_read_and_reset(dev, i);
else
btrfs_dev_stat_set(dev, i, 0);
}
btrfs_info(fs_info, "device stats zeroed by %s (%d)",
current->comm, task_pid_nr(current));
} else {
for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
if (stats->nr_items > i)
stats->values[i] = btrfs_dev_stat_read(dev, i);
}
if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX)
stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX;
return 0;
}
/*
* Update the size and bytes used for each device where it changed. This is
* delayed since we would otherwise get errors while writing out the
* superblocks.
*
* Must be invoked during transaction commit.
*/
void btrfs_commit_device_sizes(struct btrfs_transaction *trans)
{
struct btrfs_device *curr, *next;
ASSERT(trans->state == TRANS_STATE_COMMIT_DOING);
if (list_empty(&trans->dev_update_list))
return;
/*
* We don't need the device_list_mutex here. This list is owned by the
* transaction and the transaction must complete before the device is
* released.
*/
mutex_lock(&trans->fs_info->chunk_mutex);
list_for_each_entry_safe(curr, next, &trans->dev_update_list,
post_commit_list) {
list_del_init(&curr->post_commit_list);
curr->commit_total_bytes = curr->disk_total_bytes;
curr->commit_bytes_used = curr->bytes_used;
}
mutex_unlock(&trans->fs_info->chunk_mutex);
}
/*
* Multiplicity factor for simple profiles: DUP, RAID1-like and RAID10.
*/
int btrfs_bg_type_to_factor(u64 flags)
{
const int index = btrfs_bg_flags_to_raid_index(flags);
return btrfs_raid_array[index].ncopies;
}
static int verify_one_dev_extent(struct btrfs_fs_info *fs_info,
u64 chunk_offset, u64 devid,
u64 physical_offset, u64 physical_len)
{
struct btrfs_dev_lookup_args args = { .devid = devid };
struct btrfs_chunk_map *map;
struct btrfs_device *dev;
u64 stripe_len;
bool found = false;
int ret = 0;
int i;
map = btrfs_find_chunk_map(fs_info, chunk_offset, 1);
if (!map) {
btrfs_err(fs_info,
"dev extent physical offset %llu on devid %llu doesn't have corresponding chunk",
physical_offset, devid);
ret = -EUCLEAN;
goto out;
}
stripe_len = btrfs_calc_stripe_length(map);
if (physical_len != stripe_len) {
btrfs_err(fs_info,
"dev extent physical offset %llu on devid %llu length doesn't match chunk %llu, have %llu expect %llu",
physical_offset, devid, map->start, physical_len,
stripe_len);
ret = -EUCLEAN;
goto out;
}
/*
* Very old mkfs.btrfs (before v4.1) will not respect the reserved
* space. Although kernel can handle it without problem, better to warn
* the users.
*/
if (physical_offset < BTRFS_DEVICE_RANGE_RESERVED)
btrfs_warn(fs_info,
"devid %llu physical %llu len %llu inside the reserved space",
devid, physical_offset, physical_len);
for (i = 0; i < map->num_stripes; i++) {
if (map->stripes[i].dev->devid == devid &&
map->stripes[i].physical == physical_offset) {
found = true;
if (map->verified_stripes >= map->num_stripes) {
btrfs_err(fs_info,
"too many dev extents for chunk %llu found",
map->start);
ret = -EUCLEAN;
goto out;
}
map->verified_stripes++;
break;
}
}
if (!found) {
btrfs_err(fs_info,
"dev extent physical offset %llu devid %llu has no corresponding chunk",
physical_offset, devid);
ret = -EUCLEAN;
}
/* Make sure no dev extent is beyond device boundary */
dev = btrfs_find_device(fs_info->fs_devices, &args);
if (!dev) {
btrfs_err(fs_info, "failed to find devid %llu", devid);
ret = -EUCLEAN;
goto out;
}
if (physical_offset + physical_len > dev->disk_total_bytes) {
btrfs_err(fs_info,
"dev extent devid %llu physical offset %llu len %llu is beyond device boundary %llu",
devid, physical_offset, physical_len,
dev->disk_total_bytes);
ret = -EUCLEAN;
goto out;
}
if (dev->zone_info) {
u64 zone_size = dev->zone_info->zone_size;
if (!IS_ALIGNED(physical_offset, zone_size) ||
!IS_ALIGNED(physical_len, zone_size)) {
btrfs_err(fs_info,
"zoned: dev extent devid %llu physical offset %llu len %llu is not aligned to device zone",
devid, physical_offset, physical_len);
ret = -EUCLEAN;
goto out;
}
}
out:
btrfs_free_chunk_map(map);
return ret;
}
static int verify_chunk_dev_extent_mapping(struct btrfs_fs_info *fs_info)
{
struct rb_node *node;
int ret = 0;
read_lock(&fs_info->mapping_tree_lock);
for (node = rb_first_cached(&fs_info->mapping_tree); node; node = rb_next(node)) {
struct btrfs_chunk_map *map;
map = rb_entry(node, struct btrfs_chunk_map, rb_node);
if (map->num_stripes != map->verified_stripes) {
btrfs_err(fs_info,
"chunk %llu has missing dev extent, have %d expect %d",
map->start, map->verified_stripes, map->num_stripes);
ret = -EUCLEAN;
goto out;
}
}
out:
read_unlock(&fs_info->mapping_tree_lock);
return ret;
}
/*
* Ensure that all dev extents are mapped to correct chunk, otherwise
* later chunk allocation/free would cause unexpected behavior.
*
* NOTE: This will iterate through the whole device tree, which should be of
* the same size level as the chunk tree. This slightly increases mount time.
*/
int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info)
{
struct btrfs_path *path;
struct btrfs_root *root = fs_info->dev_root;
struct btrfs_key key;
u64 prev_devid = 0;
u64 prev_dev_ext_end = 0;
int ret = 0;
/*
* We don't have a dev_root because we mounted with ignorebadroots and
* failed to load the root, so we want to skip the verification in this
* case for sure.
*
* However if the dev root is fine, but the tree itself is corrupted
* we'd still fail to mount. This verification is only to make sure
* writes can happen safely, so instead just bypass this check
* completely in the case of IGNOREBADROOTS.
*/
if (btrfs_test_opt(fs_info, IGNOREBADROOTS))
return 0;
key.objectid = 1;
key.type = BTRFS_DEV_EXTENT_KEY;
key.offset = 0;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
path->reada = READA_FORWARD;
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
goto out;
if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
ret = btrfs_next_leaf(root, path);
if (ret < 0)
goto out;
/* No dev extents at all? Not good */
if (ret > 0) {
ret = -EUCLEAN;
goto out;
}
}
while (1) {
struct extent_buffer *leaf = path->nodes[0];
struct btrfs_dev_extent *dext;
int slot = path->slots[0];
u64 chunk_offset;
u64 physical_offset;
u64 physical_len;
u64 devid;
btrfs_item_key_to_cpu(leaf, &key, slot);
if (key.type != BTRFS_DEV_EXTENT_KEY)
break;
devid = key.objectid;
physical_offset = key.offset;
dext = btrfs_item_ptr(leaf, slot, struct btrfs_dev_extent);
chunk_offset = btrfs_dev_extent_chunk_offset(leaf, dext);
physical_len = btrfs_dev_extent_length(leaf, dext);
/* Check if this dev extent overlaps with the previous one */
if (devid == prev_devid && physical_offset < prev_dev_ext_end) {
btrfs_err(fs_info,
"dev extent devid %llu physical offset %llu overlap with previous dev extent end %llu",
devid, physical_offset, prev_dev_ext_end);
ret = -EUCLEAN;
goto out;
}
ret = verify_one_dev_extent(fs_info, chunk_offset, devid,
physical_offset, physical_len);
if (ret < 0)
goto out;
prev_devid = devid;
prev_dev_ext_end = physical_offset + physical_len;
ret = btrfs_next_item(root, path);
if (ret < 0)
goto out;
if (ret > 0) {
ret = 0;
break;
}
}
/* Ensure all chunks have corresponding dev extents */
ret = verify_chunk_dev_extent_mapping(fs_info);
out:
btrfs_free_path(path);
return ret;
}
/*
* Check whether the given block group or device is pinned by any inode being
* used as a swapfile.
*/
bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr)
{
struct btrfs_swapfile_pin *sp;
struct rb_node *node;
spin_lock(&fs_info->swapfile_pins_lock);
node = fs_info->swapfile_pins.rb_node;
while (node) {
sp = rb_entry(node, struct btrfs_swapfile_pin, node);
if (ptr < sp->ptr)
node = node->rb_left;
else if (ptr > sp->ptr)
node = node->rb_right;
else
break;
}
spin_unlock(&fs_info->swapfile_pins_lock);
return node != NULL;
}
static int relocating_repair_kthread(void *data)
{
struct btrfs_block_group *cache = data;
struct btrfs_fs_info *fs_info = cache->fs_info;
u64 target;
int ret = 0;
target = cache->start;
btrfs_put_block_group(cache);
sb_start_write(fs_info->sb);
if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) {
btrfs_info(fs_info,
"zoned: skip relocating block group %llu to repair: EBUSY",
target);
sb_end_write(fs_info->sb);
return -EBUSY;
}
mutex_lock(&fs_info->reclaim_bgs_lock);
/* Ensure block group still exists */
cache = btrfs_lookup_block_group(fs_info, target);
if (!cache)
goto out;
if (!test_bit(BLOCK_GROUP_FLAG_RELOCATING_REPAIR, &cache->runtime_flags))
goto out;
ret = btrfs_may_alloc_data_chunk(fs_info, target);
if (ret < 0)
goto out;
btrfs_info(fs_info,
"zoned: relocating block group %llu to repair IO failure",
target);
ret = btrfs_relocate_chunk(fs_info, target);
out:
if (cache)
btrfs_put_block_group(cache);
mutex_unlock(&fs_info->reclaim_bgs_lock);
btrfs_exclop_finish(fs_info);
sb_end_write(fs_info->sb);
return ret;
}
bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical)
{
struct btrfs_block_group *cache;
if (!btrfs_is_zoned(fs_info))
return false;
/* Do not attempt to repair in degraded state */
if (btrfs_test_opt(fs_info, DEGRADED))
return true;
cache = btrfs_lookup_block_group(fs_info, logical);
if (!cache)
return true;
if (test_and_set_bit(BLOCK_GROUP_FLAG_RELOCATING_REPAIR, &cache->runtime_flags)) {
btrfs_put_block_group(cache);
return true;
}
kthread_run(relocating_repair_kthread, cache,
"btrfs-relocating-repair");
return true;
}
static void map_raid56_repair_block(struct btrfs_io_context *bioc,
struct btrfs_io_stripe *smap,
u64 logical)
{
int data_stripes = nr_bioc_data_stripes(bioc);
int i;
for (i = 0; i < data_stripes; i++) {
u64 stripe_start = bioc->full_stripe_logical +
btrfs_stripe_nr_to_offset(i);
if (logical >= stripe_start &&
logical < stripe_start + BTRFS_STRIPE_LEN)
break;
}
ASSERT(i < data_stripes);
smap->dev = bioc->stripes[i].dev;
smap->physical = bioc->stripes[i].physical +
((logical - bioc->full_stripe_logical) &
BTRFS_STRIPE_LEN_MASK);
}
/*
* Map a repair write into a single device.
*
* A repair write is triggered by read time repair or scrub, which would only
* update the contents of a single device.
* Not update any other mirrors nor go through RMW path.
*
* Callers should ensure:
*
* - Call btrfs_bio_counter_inc_blocked() first
* - The range does not cross stripe boundary
* - Has a valid @mirror_num passed in.
*/
int btrfs_map_repair_block(struct btrfs_fs_info *fs_info,
struct btrfs_io_stripe *smap, u64 logical,
u32 length, int mirror_num)
{
struct btrfs_io_context *bioc = NULL;
u64 map_length = length;
int mirror_ret = mirror_num;
int ret;
ASSERT(mirror_num > 0);
ret = btrfs_map_block(fs_info, BTRFS_MAP_WRITE, logical, &map_length,
&bioc, smap, &mirror_ret);
if (ret < 0)
return ret;
/* The map range should not cross stripe boundary. */
ASSERT(map_length >= length);
/* Already mapped to single stripe. */
if (!bioc)
goto out;
/* Map the RAID56 multi-stripe writes to a single one. */
if (bioc->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
map_raid56_repair_block(bioc, smap, logical);
goto out;
}
ASSERT(mirror_num <= bioc->num_stripes);
smap->dev = bioc->stripes[mirror_num - 1].dev;
smap->physical = bioc->stripes[mirror_num - 1].physical;
out:
btrfs_put_bioc(bioc);
ASSERT(smap->dev);
return 0;
}
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