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linux/drivers/md/md.c
NeilBrown 6b8b3e8a8b [PATCH] md: make sure md bitmap updates are flushed when array is stopped. 
The recent change to never ignore the bitmap, revealed that the bitmap isn't
begin flushed properly when an array is stopped.

We call bitmap_daemon_work three times as there is a three-stage pipeline for
flushing updates to the bitmap file.

Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-04 13:00:54 -07:00

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/*
md.c : Multiple Devices driver for Linux
Copyright (C) 1998, 1999, 2000 Ingo Molnar
completely rewritten, based on the MD driver code from Marc Zyngier
Changes:
- RAID-1/RAID-5 extensions by Miguel de Icaza, Gadi Oxman, Ingo Molnar
- RAID-6 extensions by H. Peter Anvin <hpa@zytor.com>
- boot support for linear and striped mode by Harald Hoyer <HarryH@Royal.Net>
- kerneld support by Boris Tobotras <boris@xtalk.msk.su>
- kmod support by: Cyrus Durgin
- RAID0 bugfixes: Mark Anthony Lisher <markal@iname.com>
- Devfs support by Richard Gooch <rgooch@atnf.csiro.au>
- lots of fixes and improvements to the RAID1/RAID5 and generic
RAID code (such as request based resynchronization):
Neil Brown <neilb@cse.unsw.edu.au>.
- persistent bitmap code
Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
You should have received a copy of the GNU General Public License
(for example /usr/src/linux/COPYING); if not, write to the Free
Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/module.h>
#include <linux/config.h>
#include <linux/linkage.h>
#include <linux/raid/md.h>
#include <linux/raid/bitmap.h>
#include <linux/sysctl.h>
#include <linux/devfs_fs_kernel.h>
#include <linux/buffer_head.h> /* for invalidate_bdev */
#include <linux/suspend.h>
#include <linux/init.h>
#include <linux/file.h>
#ifdef CONFIG_KMOD
#include <linux/kmod.h>
#endif
#include <asm/unaligned.h>
#define MAJOR_NR MD_MAJOR
#define MD_DRIVER
/* 63 partitions with the alternate major number (mdp) */
#define MdpMinorShift 6
#define DEBUG 0
#define dprintk(x...) ((void)(DEBUG && printk(x)))
#ifndef MODULE
static void autostart_arrays (int part);
#endif
static mdk_personality_t *pers[MAX_PERSONALITY];
static DEFINE_SPINLOCK(pers_lock);
/*
* Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
* is 1000 KB/sec, so the extra system load does not show up that much.
* Increase it if you want to have more _guaranteed_ speed. Note that
* the RAID driver will use the maximum available bandwith if the IO
* subsystem is idle. There is also an 'absolute maximum' reconstruction
* speed limit - in case reconstruction slows down your system despite
* idle IO detection.
*
* you can change it via /proc/sys/dev/raid/speed_limit_min and _max.
*/
static int sysctl_speed_limit_min = 1000;
static int sysctl_speed_limit_max = 200000;
static struct ctl_table_header *raid_table_header;
static ctl_table raid_table[] = {
{
.ctl_name = DEV_RAID_SPEED_LIMIT_MIN,
.procname = "speed_limit_min",
.data = &sysctl_speed_limit_min,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = DEV_RAID_SPEED_LIMIT_MAX,
.procname = "speed_limit_max",
.data = &sysctl_speed_limit_max,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{ .ctl_name = 0 }
};
static ctl_table raid_dir_table[] = {
{
.ctl_name = DEV_RAID,
.procname = "raid",
.maxlen = 0,
.mode = 0555,
.child = raid_table,
},
{ .ctl_name = 0 }
};
static ctl_table raid_root_table[] = {
{
.ctl_name = CTL_DEV,
.procname = "dev",
.maxlen = 0,
.mode = 0555,
.child = raid_dir_table,
},
{ .ctl_name = 0 }
};
static struct block_device_operations md_fops;
/*
* Enables to iterate over all existing md arrays
* all_mddevs_lock protects this list.
*/
static LIST_HEAD(all_mddevs);
static DEFINE_SPINLOCK(all_mddevs_lock);
/*
* iterates through all used mddevs in the system.
* We take care to grab the all_mddevs_lock whenever navigating
* the list, and to always hold a refcount when unlocked.
* Any code which breaks out of this loop while own
* a reference to the current mddev and must mddev_put it.
*/
#define ITERATE_MDDEV(mddev,tmp) \
\
for (({ spin_lock(&all_mddevs_lock); \
tmp = all_mddevs.next; \
mddev = NULL;}); \
({ if (tmp != &all_mddevs) \
mddev_get(list_entry(tmp, mddev_t, all_mddevs));\
spin_unlock(&all_mddevs_lock); \
if (mddev) mddev_put(mddev); \
mddev = list_entry(tmp, mddev_t, all_mddevs); \
tmp != &all_mddevs;}); \
({ spin_lock(&all_mddevs_lock); \
tmp = tmp->next;}) \
)
static int md_fail_request (request_queue_t *q, struct bio *bio)
{
bio_io_error(bio, bio->bi_size);
return 0;
}
static inline mddev_t *mddev_get(mddev_t *mddev)
{
atomic_inc(&mddev->active);
return mddev;
}
static void mddev_put(mddev_t *mddev)
{
if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
return;
if (!mddev->raid_disks && list_empty(&mddev->disks)) {
list_del(&mddev->all_mddevs);
blk_put_queue(mddev->queue);
kfree(mddev);
}
spin_unlock(&all_mddevs_lock);
}
static mddev_t * mddev_find(dev_t unit)
{
mddev_t *mddev, *new = NULL;
retry:
spin_lock(&all_mddevs_lock);
list_for_each_entry(mddev, &all_mddevs, all_mddevs)
if (mddev->unit == unit) {
mddev_get(mddev);
spin_unlock(&all_mddevs_lock);
kfree(new);
return mddev;
}
if (new) {
list_add(&new->all_mddevs, &all_mddevs);
spin_unlock(&all_mddevs_lock);
return new;
}
spin_unlock(&all_mddevs_lock);
new = (mddev_t *) kmalloc(sizeof(*new), GFP_KERNEL);
if (!new)
return NULL;
memset(new, 0, sizeof(*new));
new->unit = unit;
if (MAJOR(unit) == MD_MAJOR)
new->md_minor = MINOR(unit);
else
new->md_minor = MINOR(unit) >> MdpMinorShift;
init_MUTEX(&new->reconfig_sem);
INIT_LIST_HEAD(&new->disks);
INIT_LIST_HEAD(&new->all_mddevs);
init_timer(&new->safemode_timer);
atomic_set(&new->active, 1);
spin_lock_init(&new->write_lock);
init_waitqueue_head(&new->sb_wait);
new->queue = blk_alloc_queue(GFP_KERNEL);
if (!new->queue) {
kfree(new);
return NULL;
}
blk_queue_make_request(new->queue, md_fail_request);
goto retry;
}
static inline int mddev_lock(mddev_t * mddev)
{
return down_interruptible(&mddev->reconfig_sem);
}
static inline void mddev_lock_uninterruptible(mddev_t * mddev)
{
down(&mddev->reconfig_sem);
}
static inline int mddev_trylock(mddev_t * mddev)
{
return down_trylock(&mddev->reconfig_sem);
}
static inline void mddev_unlock(mddev_t * mddev)
{
up(&mddev->reconfig_sem);
if (mddev->thread)
md_wakeup_thread(mddev->thread);
}
mdk_rdev_t * find_rdev_nr(mddev_t *mddev, int nr)
{
mdk_rdev_t * rdev;
struct list_head *tmp;
ITERATE_RDEV(mddev,rdev,tmp) {
if (rdev->desc_nr == nr)
return rdev;
}
return NULL;
}
static mdk_rdev_t * find_rdev(mddev_t * mddev, dev_t dev)
{
struct list_head *tmp;
mdk_rdev_t *rdev;
ITERATE_RDEV(mddev,rdev,tmp) {
if (rdev->bdev->bd_dev == dev)
return rdev;
}
return NULL;
}
static inline sector_t calc_dev_sboffset(struct block_device *bdev)
{
sector_t size = bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
return MD_NEW_SIZE_BLOCKS(size);
}
static sector_t calc_dev_size(mdk_rdev_t *rdev, unsigned chunk_size)
{
sector_t size;
size = rdev->sb_offset;
if (chunk_size)
size &= ~((sector_t)chunk_size/1024 - 1);
return size;
}
static int alloc_disk_sb(mdk_rdev_t * rdev)
{
if (rdev->sb_page)
MD_BUG();
rdev->sb_page = alloc_page(GFP_KERNEL);
if (!rdev->sb_page) {
printk(KERN_ALERT "md: out of memory.\n");
return -EINVAL;
}
return 0;
}
static void free_disk_sb(mdk_rdev_t * rdev)
{
if (rdev->sb_page) {
page_cache_release(rdev->sb_page);
rdev->sb_loaded = 0;
rdev->sb_page = NULL;
rdev->sb_offset = 0;
rdev->size = 0;
}
}
static int super_written(struct bio *bio, unsigned int bytes_done, int error)
{
mdk_rdev_t *rdev = bio->bi_private;
if (bio->bi_size)
return 1;
if (error || !test_bit(BIO_UPTODATE, &bio->bi_flags))
md_error(rdev->mddev, rdev);
if (atomic_dec_and_test(&rdev->mddev->pending_writes))
wake_up(&rdev->mddev->sb_wait);
bio_put(bio);
return 0;
}
void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev,
sector_t sector, int size, struct page *page)
{
/* write first size bytes of page to sector of rdev
* Increment mddev->pending_writes before returning
* and decrement it on completion, waking up sb_wait
* if zero is reached.
* If an error occurred, call md_error
*/
struct bio *bio = bio_alloc(GFP_NOIO, 1);
bio->bi_bdev = rdev->bdev;
bio->bi_sector = sector;
bio_add_page(bio, page, size, 0);
bio->bi_private = rdev;
bio->bi_end_io = super_written;
atomic_inc(&mddev->pending_writes);
submit_bio((1<<BIO_RW)|(1<<BIO_RW_SYNC), bio);
}
static int bi_complete(struct bio *bio, unsigned int bytes_done, int error)
{
if (bio->bi_size)
return 1;
complete((struct completion*)bio->bi_private);
return 0;
}
int sync_page_io(struct block_device *bdev, sector_t sector, int size,
struct page *page, int rw)
{
struct bio *bio = bio_alloc(GFP_NOIO, 1);
struct completion event;
int ret;
rw |= (1 << BIO_RW_SYNC);
bio->bi_bdev = bdev;
bio->bi_sector = sector;
bio_add_page(bio, page, size, 0);
init_completion(&event);
bio->bi_private = &event;
bio->bi_end_io = bi_complete;
submit_bio(rw, bio);
wait_for_completion(&event);
ret = test_bit(BIO_UPTODATE, &bio->bi_flags);
bio_put(bio);
return ret;
}
static int read_disk_sb(mdk_rdev_t * rdev)
{
char b[BDEVNAME_SIZE];
if (!rdev->sb_page) {
MD_BUG();
return -EINVAL;
}
if (rdev->sb_loaded)
return 0;
if (!sync_page_io(rdev->bdev, rdev->sb_offset<<1, MD_SB_BYTES, rdev->sb_page, READ))
goto fail;
rdev->sb_loaded = 1;
return 0;
fail:
printk(KERN_WARNING "md: disabled device %s, could not read superblock.\n",
bdevname(rdev->bdev,b));
return -EINVAL;
}
static int uuid_equal(mdp_super_t *sb1, mdp_super_t *sb2)
{
if ( (sb1->set_uuid0 == sb2->set_uuid0) &&
(sb1->set_uuid1 == sb2->set_uuid1) &&
(sb1->set_uuid2 == sb2->set_uuid2) &&
(sb1->set_uuid3 == sb2->set_uuid3))
return 1;
return 0;
}
static int sb_equal(mdp_super_t *sb1, mdp_super_t *sb2)
{
int ret;
mdp_super_t *tmp1, *tmp2;
tmp1 = kmalloc(sizeof(*tmp1),GFP_KERNEL);
tmp2 = kmalloc(sizeof(*tmp2),GFP_KERNEL);
if (!tmp1 || !tmp2) {
ret = 0;
printk(KERN_INFO "md.c: sb1 is not equal to sb2!\n");
goto abort;
}
*tmp1 = *sb1;
*tmp2 = *sb2;
/*
* nr_disks is not constant
*/
tmp1->nr_disks = 0;
tmp2->nr_disks = 0;
if (memcmp(tmp1, tmp2, MD_SB_GENERIC_CONSTANT_WORDS * 4))
ret = 0;
else
ret = 1;
abort:
kfree(tmp1);
kfree(tmp2);
return ret;
}
static unsigned int calc_sb_csum(mdp_super_t * sb)
{
unsigned int disk_csum, csum;
disk_csum = sb->sb_csum;
sb->sb_csum = 0;
csum = csum_partial((void *)sb, MD_SB_BYTES, 0);
sb->sb_csum = disk_csum;
return csum;
}
/*
* Handle superblock details.
* We want to be able to handle multiple superblock formats
* so we have a common interface to them all, and an array of
* different handlers.
* We rely on user-space to write the initial superblock, and support
* reading and updating of superblocks.
* Interface methods are:
* int load_super(mdk_rdev_t *dev, mdk_rdev_t *refdev, int minor_version)
* loads and validates a superblock on dev.
* if refdev != NULL, compare superblocks on both devices
* Return:
* 0 - dev has a superblock that is compatible with refdev
* 1 - dev has a superblock that is compatible and newer than refdev
* so dev should be used as the refdev in future
* -EINVAL superblock incompatible or invalid
* -othererror e.g. -EIO
*
* int validate_super(mddev_t *mddev, mdk_rdev_t *dev)
* Verify that dev is acceptable into mddev.
* The first time, mddev->raid_disks will be 0, and data from
* dev should be merged in. Subsequent calls check that dev
* is new enough. Return 0 or -EINVAL
*
* void sync_super(mddev_t *mddev, mdk_rdev_t *dev)
* Update the superblock for rdev with data in mddev
* This does not write to disc.
*
*/
struct super_type {
char *name;
struct module *owner;
int (*load_super)(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version);
int (*validate_super)(mddev_t *mddev, mdk_rdev_t *rdev);
void (*sync_super)(mddev_t *mddev, mdk_rdev_t *rdev);
};
/*
* load_super for 0.90.0
*/
static int super_90_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
{
char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
mdp_super_t *sb;
int ret;
sector_t sb_offset;
/*
* Calculate the position of the superblock,
* it's at the end of the disk.
*
* It also happens to be a multiple of 4Kb.
*/
sb_offset = calc_dev_sboffset(rdev->bdev);
rdev->sb_offset = sb_offset;
ret = read_disk_sb(rdev);
if (ret) return ret;
ret = -EINVAL;
bdevname(rdev->bdev, b);
sb = (mdp_super_t*)page_address(rdev->sb_page);
if (sb->md_magic != MD_SB_MAGIC) {
printk(KERN_ERR "md: invalid raid superblock magic on %s\n",
b);
goto abort;
}
if (sb->major_version != 0 ||
sb->minor_version != 90) {
printk(KERN_WARNING "Bad version number %d.%d on %s\n",
sb->major_version, sb->minor_version,
b);
goto abort;
}
if (sb->raid_disks <= 0)
goto abort;
if (csum_fold(calc_sb_csum(sb)) != csum_fold(sb->sb_csum)) {
printk(KERN_WARNING "md: invalid superblock checksum on %s\n",
b);
goto abort;
}
rdev->preferred_minor = sb->md_minor;
rdev->data_offset = 0;
if (sb->level == LEVEL_MULTIPATH)
rdev->desc_nr = -1;
else
rdev->desc_nr = sb->this_disk.number;
if (refdev == 0)
ret = 1;
else {
__u64 ev1, ev2;
mdp_super_t *refsb = (mdp_super_t*)page_address(refdev->sb_page);
if (!uuid_equal(refsb, sb)) {
printk(KERN_WARNING "md: %s has different UUID to %s\n",
b, bdevname(refdev->bdev,b2));
goto abort;
}
if (!sb_equal(refsb, sb)) {
printk(KERN_WARNING "md: %s has same UUID"
" but different superblock to %s\n",
b, bdevname(refdev->bdev, b2));
goto abort;
}
ev1 = md_event(sb);
ev2 = md_event(refsb);
if (ev1 > ev2)
ret = 1;
else
ret = 0;
}
rdev->size = calc_dev_size(rdev, sb->chunk_size);
abort:
return ret;
}
/*
* validate_super for 0.90.0
*/
static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
{
mdp_disk_t *desc;
mdp_super_t *sb = (mdp_super_t *)page_address(rdev->sb_page);
rdev->raid_disk = -1;
rdev->in_sync = 0;
if (mddev->raid_disks == 0) {
mddev->major_version = 0;
mddev->minor_version = sb->minor_version;
mddev->patch_version = sb->patch_version;
mddev->persistent = ! sb->not_persistent;
mddev->chunk_size = sb->chunk_size;
mddev->ctime = sb->ctime;
mddev->utime = sb->utime;
mddev->level = sb->level;
mddev->layout = sb->layout;
mddev->raid_disks = sb->raid_disks;
mddev->size = sb->size;
mddev->events = md_event(sb);
if (sb->state & (1<<MD_SB_CLEAN))
mddev->recovery_cp = MaxSector;
else {
if (sb->events_hi == sb->cp_events_hi &&
sb->events_lo == sb->cp_events_lo) {
mddev->recovery_cp = sb->recovery_cp;
} else
mddev->recovery_cp = 0;
}
memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
mddev->max_disks = MD_SB_DISKS;
if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
mddev->bitmap_file == NULL) {
if (mddev->level != 1) {
/* FIXME use a better test */
printk(KERN_WARNING "md: bitmaps only support for raid1\n");
return -EINVAL;
}
mddev->bitmap_offset = (MD_SB_BYTES >> 9);
}
} else if (mddev->pers == NULL) {
/* Insist on good event counter while assembling */
__u64 ev1 = md_event(sb);
++ev1;
if (ev1 < mddev->events)
return -EINVAL;
} else if (mddev->bitmap) {
/* if adding to array with a bitmap, then we can accept an
* older device ... but not too old.
*/
__u64 ev1 = md_event(sb);
if (ev1 < mddev->bitmap->events_cleared)
return 0;
} else /* just a hot-add of a new device, leave raid_disk at -1 */
return 0;
if (mddev->level != LEVEL_MULTIPATH) {
rdev->faulty = 0;
desc = sb->disks + rdev->desc_nr;
if (desc->state & (1<<MD_DISK_FAULTY))
rdev->faulty = 1;
else if (desc->state & (1<<MD_DISK_SYNC) &&
desc->raid_disk < mddev->raid_disks) {
rdev->in_sync = 1;
rdev->raid_disk = desc->raid_disk;
}
} else /* MULTIPATH are always insync */
rdev->in_sync = 1;
return 0;
}
/*
* sync_super for 0.90.0
*/
static void super_90_sync(mddev_t *mddev, mdk_rdev_t *rdev)
{
mdp_super_t *sb;
struct list_head *tmp;
mdk_rdev_t *rdev2;
int next_spare = mddev->raid_disks;
/* make rdev->sb match mddev data..
*
* 1/ zero out disks
* 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
* 3/ any empty disks < next_spare become removed
*
* disks[0] gets initialised to REMOVED because
* we cannot be sure from other fields if it has
* been initialised or not.
*/
int i;
int active=0, working=0,failed=0,spare=0,nr_disks=0;
sb = (mdp_super_t*)page_address(rdev->sb_page);
memset(sb, 0, sizeof(*sb));
sb->md_magic = MD_SB_MAGIC;
sb->major_version = mddev->major_version;
sb->minor_version = mddev->minor_version;
sb->patch_version = mddev->patch_version;
sb->gvalid_words = 0; /* ignored */
memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
memcpy(&sb->set_uuid3, mddev->uuid+12,4);
sb->ctime = mddev->ctime;
sb->level = mddev->level;
sb->size = mddev->size;
sb->raid_disks = mddev->raid_disks;
sb->md_minor = mddev->md_minor;
sb->not_persistent = !mddev->persistent;
sb->utime = mddev->utime;
sb->state = 0;
sb->events_hi = (mddev->events>>32);
sb->events_lo = (u32)mddev->events;
if (mddev->in_sync)
{
sb->recovery_cp = mddev->recovery_cp;
sb->cp_events_hi = (mddev->events>>32);
sb->cp_events_lo = (u32)mddev->events;
if (mddev->recovery_cp == MaxSector)
sb->state = (1<< MD_SB_CLEAN);
} else
sb->recovery_cp = 0;
sb->layout = mddev->layout;
sb->chunk_size = mddev->chunk_size;
if (mddev->bitmap && mddev->bitmap_file == NULL)
sb->state |= (1<<MD_SB_BITMAP_PRESENT);
sb->disks[0].state = (1<<MD_DISK_REMOVED);
ITERATE_RDEV(mddev,rdev2,tmp) {
mdp_disk_t *d;
if (rdev2->raid_disk >= 0 && rdev2->in_sync && !rdev2->faulty)
rdev2->desc_nr = rdev2->raid_disk;
else
rdev2->desc_nr = next_spare++;
d = &sb->disks[rdev2->desc_nr];
nr_disks++;
d->number = rdev2->desc_nr;
d->major = MAJOR(rdev2->bdev->bd_dev);
d->minor = MINOR(rdev2->bdev->bd_dev);
if (rdev2->raid_disk >= 0 && rdev->in_sync && !rdev2->faulty)
d->raid_disk = rdev2->raid_disk;
else
d->raid_disk = rdev2->desc_nr; /* compatibility */
if (rdev2->faulty) {
d->state = (1<<MD_DISK_FAULTY);
failed++;
} else if (rdev2->in_sync) {
d->state = (1<<MD_DISK_ACTIVE);
d->state |= (1<<MD_DISK_SYNC);
active++;
working++;
} else {
d->state = 0;
spare++;
working++;
}
}
/* now set the "removed" and "faulty" bits on any missing devices */
for (i=0 ; i < mddev->raid_disks ; i++) {
mdp_disk_t *d = &sb->disks[i];
if (d->state == 0 && d->number == 0) {
d->number = i;
d->raid_disk = i;
d->state = (1<<MD_DISK_REMOVED);
d->state |= (1<<MD_DISK_FAULTY);
failed++;
}
}
sb->nr_disks = nr_disks;
sb->active_disks = active;
sb->working_disks = working;
sb->failed_disks = failed;
sb->spare_disks = spare;
sb->this_disk = sb->disks[rdev->desc_nr];
sb->sb_csum = calc_sb_csum(sb);
}
/*
* version 1 superblock
*/
static unsigned int calc_sb_1_csum(struct mdp_superblock_1 * sb)
{
unsigned int disk_csum, csum;
unsigned long long newcsum;
int size = 256 + le32_to_cpu(sb->max_dev)*2;
unsigned int *isuper = (unsigned int*)sb;
int i;
disk_csum = sb->sb_csum;
sb->sb_csum = 0;
newcsum = 0;
for (i=0; size>=4; size -= 4 )
newcsum += le32_to_cpu(*isuper++);
if (size == 2)
newcsum += le16_to_cpu(*(unsigned short*) isuper);
csum = (newcsum & 0xffffffff) + (newcsum >> 32);
sb->sb_csum = disk_csum;
return cpu_to_le32(csum);
}
static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
{
struct mdp_superblock_1 *sb;
int ret;
sector_t sb_offset;
char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
/*
* Calculate the position of the superblock.
* It is always aligned to a 4K boundary and
* depeding on minor_version, it can be:
* 0: At least 8K, but less than 12K, from end of device
* 1: At start of device
* 2: 4K from start of device.
*/
switch(minor_version) {
case 0:
sb_offset = rdev->bdev->bd_inode->i_size >> 9;
sb_offset -= 8*2;
sb_offset &= ~(sector_t)(4*2-1);
/* convert from sectors to K */
sb_offset /= 2;
break;
case 1:
sb_offset = 0;
break;
case 2:
sb_offset = 4;
break;
default:
return -EINVAL;
}
rdev->sb_offset = sb_offset;
ret = read_disk_sb(rdev);
if (ret) return ret;
sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
sb->major_version != cpu_to_le32(1) ||
le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
le64_to_cpu(sb->super_offset) != (rdev->sb_offset<<1) ||
sb->feature_map != 0)
return -EINVAL;
if (calc_sb_1_csum(sb) != sb->sb_csum) {
printk("md: invalid superblock checksum on %s\n",
bdevname(rdev->bdev,b));
return -EINVAL;
}
if (le64_to_cpu(sb->data_size) < 10) {
printk("md: data_size too small on %s\n",
bdevname(rdev->bdev,b));
return -EINVAL;
}
rdev->preferred_minor = 0xffff;
rdev->data_offset = le64_to_cpu(sb->data_offset);
if (refdev == 0)
return 1;
else {
__u64 ev1, ev2;
struct mdp_superblock_1 *refsb =
(struct mdp_superblock_1*)page_address(refdev->sb_page);
if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
sb->level != refsb->level ||
sb->layout != refsb->layout ||
sb->chunksize != refsb->chunksize) {
printk(KERN_WARNING "md: %s has strangely different"
" superblock to %s\n",
bdevname(rdev->bdev,b),
bdevname(refdev->bdev,b2));
return -EINVAL;
}
ev1 = le64_to_cpu(sb->events);
ev2 = le64_to_cpu(refsb->events);
if (ev1 > ev2)
return 1;
}
if (minor_version)
rdev->size = ((rdev->bdev->bd_inode->i_size>>9) - le64_to_cpu(sb->data_offset)) / 2;
else
rdev->size = rdev->sb_offset;
if (rdev->size < le64_to_cpu(sb->data_size)/2)
return -EINVAL;
rdev->size = le64_to_cpu(sb->data_size)/2;
if (le32_to_cpu(sb->chunksize))
rdev->size &= ~((sector_t)le32_to_cpu(sb->chunksize)/2 - 1);
return 0;
}
static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
{
struct mdp_superblock_1 *sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
rdev->raid_disk = -1;
rdev->in_sync = 0;
if (mddev->raid_disks == 0) {
mddev->major_version = 1;
mddev->patch_version = 0;
mddev->persistent = 1;
mddev->chunk_size = le32_to_cpu(sb->chunksize) << 9;
mddev->ctime = le64_to_cpu(sb->ctime) & ((1ULL << 32)-1);
mddev->utime = le64_to_cpu(sb->utime) & ((1ULL << 32)-1);
mddev->level = le32_to_cpu(sb->level);
mddev->layout = le32_to_cpu(sb->layout);
mddev->raid_disks = le32_to_cpu(sb->raid_disks);
mddev->size = le64_to_cpu(sb->size)/2;
mddev->events = le64_to_cpu(sb->events);
mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
memcpy(mddev->uuid, sb->set_uuid, 16);
mddev->max_disks = (4096-256)/2;
if ((le32_to_cpu(sb->feature_map) & 1) &&
mddev->bitmap_file == NULL ) {
if (mddev->level != 1) {
printk(KERN_WARNING "md: bitmaps only supported for raid1\n");
return -EINVAL;
}
mddev->bitmap_offset = (__s32)le32_to_cpu(sb->bitmap_offset);
}
} else if (mddev->pers == NULL) {
/* Insist of good event counter while assembling */
__u64 ev1 = le64_to_cpu(sb->events);
++ev1;
if (ev1 < mddev->events)
return -EINVAL;
} else if (mddev->bitmap) {
/* If adding to array with a bitmap, then we can accept an
* older device, but not too old.
*/
__u64 ev1 = le64_to_cpu(sb->events);
if (ev1 < mddev->bitmap->events_cleared)
return 0;
} else /* just a hot-add of a new device, leave raid_disk at -1 */
return 0;
if (mddev->level != LEVEL_MULTIPATH) {
int role;
rdev->desc_nr = le32_to_cpu(sb->dev_number);
role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
switch(role) {
case 0xffff: /* spare */
rdev->faulty = 0;
break;
case 0xfffe: /* faulty */
rdev->faulty = 1;
break;
default:
rdev->in_sync = 1;
rdev->faulty = 0;
rdev->raid_disk = role;
break;
}
} else /* MULTIPATH are always insync */
rdev->in_sync = 1;
return 0;
}
static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
{
struct mdp_superblock_1 *sb;
struct list_head *tmp;
mdk_rdev_t *rdev2;
int max_dev, i;
/* make rdev->sb match mddev and rdev data. */
sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
sb->feature_map = 0;
sb->pad0 = 0;
memset(sb->pad1, 0, sizeof(sb->pad1));
memset(sb->pad2, 0, sizeof(sb->pad2));
memset(sb->pad3, 0, sizeof(sb->pad3));
sb->utime = cpu_to_le64((__u64)mddev->utime);
sb->events = cpu_to_le64(mddev->events);
if (mddev->in_sync)
sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
else
sb->resync_offset = cpu_to_le64(0);
if (mddev->bitmap && mddev->bitmap_file == NULL) {
sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_offset);
sb->feature_map = cpu_to_le32(1);
}
max_dev = 0;
ITERATE_RDEV(mddev,rdev2,tmp)
if (rdev2->desc_nr+1 > max_dev)
max_dev = rdev2->desc_nr+1;
sb->max_dev = cpu_to_le32(max_dev);
for (i=0; i<max_dev;i++)
sb->dev_roles[i] = cpu_to_le16(0xfffe);
ITERATE_RDEV(mddev,rdev2,tmp) {
i = rdev2->desc_nr;
if (rdev2->faulty)
sb->dev_roles[i] = cpu_to_le16(0xfffe);
else if (rdev2->in_sync)
sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
else
sb->dev_roles[i] = cpu_to_le16(0xffff);
}
sb->recovery_offset = cpu_to_le64(0); /* not supported yet */
sb->sb_csum = calc_sb_1_csum(sb);
}
static struct super_type super_types[] = {
[0] = {
.name = "0.90.0",
.owner = THIS_MODULE,
.load_super = super_90_load,
.validate_super = super_90_validate,
.sync_super = super_90_sync,
},
[1] = {
.name = "md-1",
.owner = THIS_MODULE,
.load_super = super_1_load,
.validate_super = super_1_validate,
.sync_super = super_1_sync,
},
};
static mdk_rdev_t * match_dev_unit(mddev_t *mddev, mdk_rdev_t *dev)
{
struct list_head *tmp;
mdk_rdev_t *rdev;
ITERATE_RDEV(mddev,rdev,tmp)
if (rdev->bdev->bd_contains == dev->bdev->bd_contains)
return rdev;
return NULL;
}
static int match_mddev_units(mddev_t *mddev1, mddev_t *mddev2)
{
struct list_head *tmp;
mdk_rdev_t *rdev;
ITERATE_RDEV(mddev1,rdev,tmp)
if (match_dev_unit(mddev2, rdev))
return 1;
return 0;
}
static LIST_HEAD(pending_raid_disks);
static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
{
mdk_rdev_t *same_pdev;
char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
if (rdev->mddev) {
MD_BUG();
return -EINVAL;
}
same_pdev = match_dev_unit(mddev, rdev);
if (same_pdev)
printk(KERN_WARNING
"%s: WARNING: %s appears to be on the same physical"
" disk as %s. True\n protection against single-disk"
" failure might be compromised.\n",
mdname(mddev), bdevname(rdev->bdev,b),
bdevname(same_pdev->bdev,b2));
/* Verify rdev->desc_nr is unique.
* If it is -1, assign a free number, else
* check number is not in use
*/
if (rdev->desc_nr < 0) {
int choice = 0;
if (mddev->pers) choice = mddev->raid_disks;
while (find_rdev_nr(mddev, choice))
choice++;
rdev->desc_nr = choice;
} else {
if (find_rdev_nr(mddev, rdev->desc_nr))
return -EBUSY;
}
list_add(&rdev->same_set, &mddev->disks);
rdev->mddev = mddev;
printk(KERN_INFO "md: bind<%s>\n", bdevname(rdev->bdev,b));
return 0;
}
static void unbind_rdev_from_array(mdk_rdev_t * rdev)
{
char b[BDEVNAME_SIZE];
if (!rdev->mddev) {
MD_BUG();
return;
}
list_del_init(&rdev->same_set);
printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
rdev->mddev = NULL;
}
/*
* prevent the device from being mounted, repartitioned or
* otherwise reused by a RAID array (or any other kernel
* subsystem), by bd_claiming the device.
*/
static int lock_rdev(mdk_rdev_t *rdev, dev_t dev)
{
int err = 0;
struct block_device *bdev;
char b[BDEVNAME_SIZE];
bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
if (IS_ERR(bdev)) {
printk(KERN_ERR "md: could not open %s.\n",
__bdevname(dev, b));
return PTR_ERR(bdev);
}
err = bd_claim(bdev, rdev);
if (err) {
printk(KERN_ERR "md: could not bd_claim %s.\n",
bdevname(bdev, b));
blkdev_put(bdev);
return err;
}
rdev->bdev = bdev;
return err;
}
static void unlock_rdev(mdk_rdev_t *rdev)
{
struct block_device *bdev = rdev->bdev;
rdev->bdev = NULL;
if (!bdev)
MD_BUG();
bd_release(bdev);
blkdev_put(bdev);
}
void md_autodetect_dev(dev_t dev);
static void export_rdev(mdk_rdev_t * rdev)
{
char b[BDEVNAME_SIZE];
printk(KERN_INFO "md: export_rdev(%s)\n",
bdevname(rdev->bdev,b));
if (rdev->mddev)
MD_BUG();
free_disk_sb(rdev);
list_del_init(&rdev->same_set);
#ifndef MODULE
md_autodetect_dev(rdev->bdev->bd_dev);
#endif
unlock_rdev(rdev);
kfree(rdev);
}
static void kick_rdev_from_array(mdk_rdev_t * rdev)
{
unbind_rdev_from_array(rdev);
export_rdev(rdev);
}
static void export_array(mddev_t *mddev)
{
struct list_head *tmp;
mdk_rdev_t *rdev;
ITERATE_RDEV(mddev,rdev,tmp) {
if (!rdev->mddev) {
MD_BUG();
continue;
}
kick_rdev_from_array(rdev);
}
if (!list_empty(&mddev->disks))
MD_BUG();
mddev->raid_disks = 0;
mddev->major_version = 0;
}
static void print_desc(mdp_disk_t *desc)
{
printk(" DISK<N:%d,(%d,%d),R:%d,S:%d>\n", desc->number,
desc->major,desc->minor,desc->raid_disk,desc->state);
}
static void print_sb(mdp_super_t *sb)
{
int i;
printk(KERN_INFO
"md: SB: (V:%d.%d.%d) ID:<%08x.%08x.%08x.%08x> CT:%08x\n",
sb->major_version, sb->minor_version, sb->patch_version,
sb->set_uuid0, sb->set_uuid1, sb->set_uuid2, sb->set_uuid3,
sb->ctime);
printk(KERN_INFO "md: L%d S%08d ND:%d RD:%d md%d LO:%d CS:%d\n",
sb->level, sb->size, sb->nr_disks, sb->raid_disks,
sb->md_minor, sb->layout, sb->chunk_size);
printk(KERN_INFO "md: UT:%08x ST:%d AD:%d WD:%d"
" FD:%d SD:%d CSUM:%08x E:%08lx\n",
sb->utime, sb->state, sb->active_disks, sb->working_disks,
sb->failed_disks, sb->spare_disks,
sb->sb_csum, (unsigned long)sb->events_lo);
printk(KERN_INFO);
for (i = 0; i < MD_SB_DISKS; i++) {
mdp_disk_t *desc;
desc = sb->disks + i;
if (desc->number || desc->major || desc->minor ||
desc->raid_disk || (desc->state && (desc->state != 4))) {
printk(" D %2d: ", i);
print_desc(desc);
}
}
printk(KERN_INFO "md: THIS: ");
print_desc(&sb->this_disk);
}
static void print_rdev(mdk_rdev_t *rdev)
{
char b[BDEVNAME_SIZE];
printk(KERN_INFO "md: rdev %s, SZ:%08llu F:%d S:%d DN:%u\n",
bdevname(rdev->bdev,b), (unsigned long long)rdev->size,
rdev->faulty, rdev->in_sync, rdev->desc_nr);
if (rdev->sb_loaded) {
printk(KERN_INFO "md: rdev superblock:\n");
print_sb((mdp_super_t*)page_address(rdev->sb_page));
} else
printk(KERN_INFO "md: no rdev superblock!\n");
}
void md_print_devices(void)
{
struct list_head *tmp, *tmp2;
mdk_rdev_t *rdev;
mddev_t *mddev;
char b[BDEVNAME_SIZE];
printk("\n");
printk("md: **********************************\n");
printk("md: * <COMPLETE RAID STATE PRINTOUT> *\n");
printk("md: **********************************\n");
ITERATE_MDDEV(mddev,tmp) {
if (mddev->bitmap)
bitmap_print_sb(mddev->bitmap);
else
printk("%s: ", mdname(mddev));
ITERATE_RDEV(mddev,rdev,tmp2)
printk("<%s>", bdevname(rdev->bdev,b));
printk("\n");
ITERATE_RDEV(mddev,rdev,tmp2)
print_rdev(rdev);
}
printk("md: **********************************\n");
printk("\n");
}
static void sync_sbs(mddev_t * mddev)
{
mdk_rdev_t *rdev;
struct list_head *tmp;
ITERATE_RDEV(mddev,rdev,tmp) {
super_types[mddev->major_version].
sync_super(mddev, rdev);
rdev->sb_loaded = 1;
}
}
static void md_update_sb(mddev_t * mddev)
{
int err;
struct list_head *tmp;
mdk_rdev_t *rdev;
int sync_req;
repeat:
spin_lock(&mddev->write_lock);
sync_req = mddev->in_sync;
mddev->utime = get_seconds();
mddev->events ++;
if (!mddev->events) {
/*
* oops, this 64-bit counter should never wrap.
* Either we are in around ~1 trillion A.C., assuming
* 1 reboot per second, or we have a bug:
*/
MD_BUG();
mddev->events --;
}
mddev->sb_dirty = 2;
sync_sbs(mddev);
/*
* do not write anything to disk if using
* nonpersistent superblocks
*/
if (!mddev->persistent) {
mddev->sb_dirty = 0;
spin_unlock(&mddev->write_lock);
wake_up(&mddev->sb_wait);
return;
}
spin_unlock(&mddev->write_lock);
dprintk(KERN_INFO
"md: updating %s RAID superblock on device (in sync %d)\n",
mdname(mddev),mddev->in_sync);
err = bitmap_update_sb(mddev->bitmap);
ITERATE_RDEV(mddev,rdev,tmp) {
char b[BDEVNAME_SIZE];
dprintk(KERN_INFO "md: ");
if (rdev->faulty)
dprintk("(skipping faulty ");
dprintk("%s ", bdevname(rdev->bdev,b));
if (!rdev->faulty) {
md_super_write(mddev,rdev,
rdev->sb_offset<<1, MD_SB_BYTES,
rdev->sb_page);
dprintk(KERN_INFO "(write) %s's sb offset: %llu\n",
bdevname(rdev->bdev,b),
(unsigned long long)rdev->sb_offset);
} else
dprintk(")\n");
if (mddev->level == LEVEL_MULTIPATH)
/* only need to write one superblock... */
break;
}
wait_event(mddev->sb_wait, atomic_read(&mddev->pending_writes)==0);
/* if there was a failure, sb_dirty was set to 1, and we re-write super */
spin_lock(&mddev->write_lock);
if (mddev->in_sync != sync_req|| mddev->sb_dirty == 1) {
/* have to write it out again */
spin_unlock(&mddev->write_lock);
goto repeat;
}
mddev->sb_dirty = 0;
spin_unlock(&mddev->write_lock);
wake_up(&mddev->sb_wait);
}
/*
* Import a device. If 'super_format' >= 0, then sanity check the superblock
*
* mark the device faulty if:
*
* - the device is nonexistent (zero size)
* - the device has no valid superblock
*
* a faulty rdev _never_ has rdev->sb set.
*/
static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_minor)
{
char b[BDEVNAME_SIZE];
int err;
mdk_rdev_t *rdev;
sector_t size;
rdev = (mdk_rdev_t *) kmalloc(sizeof(*rdev), GFP_KERNEL);
if (!rdev) {
printk(KERN_ERR "md: could not alloc mem for new device!\n");
return ERR_PTR(-ENOMEM);
}
memset(rdev, 0, sizeof(*rdev));
if ((err = alloc_disk_sb(rdev)))
goto abort_free;
err = lock_rdev(rdev, newdev);
if (err)
goto abort_free;
rdev->desc_nr = -1;
rdev->faulty = 0;
rdev->in_sync = 0;
rdev->data_offset = 0;
atomic_set(&rdev->nr_pending, 0);
size = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
if (!size) {
printk(KERN_WARNING
"md: %s has zero or unknown size, marking faulty!\n",
bdevname(rdev->bdev,b));
err = -EINVAL;
goto abort_free;
}
if (super_format >= 0) {
err = super_types[super_format].
load_super(rdev, NULL, super_minor);
if (err == -EINVAL) {
printk(KERN_WARNING
"md: %s has invalid sb, not importing!\n",
bdevname(rdev->bdev,b));
goto abort_free;
}
if (err < 0) {
printk(KERN_WARNING
"md: could not read %s's sb, not importing!\n",
bdevname(rdev->bdev,b));
goto abort_free;
}
}
INIT_LIST_HEAD(&rdev->same_set);
return rdev;
abort_free:
if (rdev->sb_page) {
if (rdev->bdev)
unlock_rdev(rdev);
free_disk_sb(rdev);
}
kfree(rdev);
return ERR_PTR(err);
}
/*
* Check a full RAID array for plausibility
*/
static void analyze_sbs(mddev_t * mddev)
{
int i;
struct list_head *tmp;
mdk_rdev_t *rdev, *freshest;
char b[BDEVNAME_SIZE];
freshest = NULL;
ITERATE_RDEV(mddev,rdev,tmp)
switch (super_types[mddev->major_version].
load_super(rdev, freshest, mddev->minor_version)) {
case 1:
freshest = rdev;
break;
case 0:
break;
default:
printk( KERN_ERR \
"md: fatal superblock inconsistency in %s"
" -- removing from array\n",
bdevname(rdev->bdev,b));
kick_rdev_from_array(rdev);
}
super_types[mddev->major_version].
validate_super(mddev, freshest);
i = 0;
ITERATE_RDEV(mddev,rdev,tmp) {
if (rdev != freshest)
if (super_types[mddev->major_version].
validate_super(mddev, rdev)) {
printk(KERN_WARNING "md: kicking non-fresh %s"
" from array!\n",
bdevname(rdev->bdev,b));
kick_rdev_from_array(rdev);
continue;
}
if (mddev->level == LEVEL_MULTIPATH) {
rdev->desc_nr = i++;
rdev->raid_disk = rdev->desc_nr;
rdev->in_sync = 1;
}
}
if (mddev->recovery_cp != MaxSector &&
mddev->level >= 1)
printk(KERN_ERR "md: %s: raid array is not clean"
" -- starting background reconstruction\n",
mdname(mddev));
}
int mdp_major = 0;
static struct kobject *md_probe(dev_t dev, int *part, void *data)
{
static DECLARE_MUTEX(disks_sem);
mddev_t *mddev = mddev_find(dev);
struct gendisk *disk;
int partitioned = (MAJOR(dev) != MD_MAJOR);
int shift = partitioned ? MdpMinorShift : 0;
int unit = MINOR(dev) >> shift;
if (!mddev)
return NULL;
down(&disks_sem);
if (mddev->gendisk) {
up(&disks_sem);
mddev_put(mddev);
return NULL;
}
disk = alloc_disk(1 << shift);
if (!disk) {
up(&disks_sem);
mddev_put(mddev);
return NULL;
}
disk->major = MAJOR(dev);
disk->first_minor = unit << shift;
if (partitioned) {
sprintf(disk->disk_name, "md_d%d", unit);
sprintf(disk->devfs_name, "md/d%d", unit);
} else {
sprintf(disk->disk_name, "md%d", unit);
sprintf(disk->devfs_name, "md/%d", unit);
}
disk->fops = &md_fops;
disk->private_data = mddev;
disk->queue = mddev->queue;
add_disk(disk);
mddev->gendisk = disk;
up(&disks_sem);
return NULL;
}
void md_wakeup_thread(mdk_thread_t *thread);
static void md_safemode_timeout(unsigned long data)
{
mddev_t *mddev = (mddev_t *) data;
mddev->safemode = 1;
md_wakeup_thread(mddev->thread);
}
static int do_md_run(mddev_t * mddev)
{
int pnum, err;
int chunk_size;
struct list_head *tmp;
mdk_rdev_t *rdev;
struct gendisk *disk;
char b[BDEVNAME_SIZE];
if (list_empty(&mddev->disks))
/* cannot run an array with no devices.. */
return -EINVAL;
if (mddev->pers)
return -EBUSY;
/*
* Analyze all RAID superblock(s)
*/
if (!mddev->raid_disks)
analyze_sbs(mddev);
chunk_size = mddev->chunk_size;
pnum = level_to_pers(mddev->level);
if ((pnum != MULTIPATH) && (pnum != RAID1)) {
if (!chunk_size) {
/*
* 'default chunksize' in the old md code used to
* be PAGE_SIZE, baaad.
* we abort here to be on the safe side. We don't
* want to continue the bad practice.
*/
printk(KERN_ERR
"no chunksize specified, see 'man raidtab'\n");
return -EINVAL;
}
if (chunk_size > MAX_CHUNK_SIZE) {
printk(KERN_ERR "too big chunk_size: %d > %d\n",
chunk_size, MAX_CHUNK_SIZE);
return -EINVAL;
}
/*
* chunk-size has to be a power of 2 and multiples of PAGE_SIZE
*/
if ( (1 << ffz(~chunk_size)) != chunk_size) {
printk(KERN_ERR "chunk_size of %d not valid\n", chunk_size);
return -EINVAL;
}
if (chunk_size < PAGE_SIZE) {
printk(KERN_ERR "too small chunk_size: %d < %ld\n",
chunk_size, PAGE_SIZE);
return -EINVAL;
}
/* devices must have minimum size of one chunk */
ITERATE_RDEV(mddev,rdev,tmp) {
if (rdev->faulty)
continue;
if (rdev->size < chunk_size / 1024) {
printk(KERN_WARNING
"md: Dev %s smaller than chunk_size:"
" %lluk < %dk\n",
bdevname(rdev->bdev,b),
(unsigned long long)rdev->size,
chunk_size / 1024);
return -EINVAL;
}
}
}
#ifdef CONFIG_KMOD
if (!pers[pnum])
{
request_module("md-personality-%d", pnum);
}
#endif
/*
* Drop all container device buffers, from now on
* the only valid external interface is through the md
* device.
* Also find largest hardsector size
*/
ITERATE_RDEV(mddev,rdev,tmp) {
if (rdev->faulty)
continue;
sync_blockdev(rdev->bdev);
invalidate_bdev(rdev->bdev, 0);
}
md_probe(mddev->unit, NULL, NULL);
disk = mddev->gendisk;
if (!disk)
return -ENOMEM;
spin_lock(&pers_lock);
if (!pers[pnum] || !try_module_get(pers[pnum]->owner)) {
spin_unlock(&pers_lock);
printk(KERN_WARNING "md: personality %d is not loaded!\n",
pnum);
return -EINVAL;
}
mddev->pers = pers[pnum];
spin_unlock(&pers_lock);
mddev->resync_max_sectors = mddev->size << 1; /* may be over-ridden by personality */
/* before we start the array running, initialise the bitmap */
err = bitmap_create(mddev);
if (err)
printk(KERN_ERR "%s: failed to create bitmap (%d)\n",
mdname(mddev), err);
else
err = mddev->pers->run(mddev);
if (err) {
printk(KERN_ERR "md: pers->run() failed ...\n");
module_put(mddev->pers->owner);
mddev->pers = NULL;
bitmap_destroy(mddev);
return err;
}
atomic_set(&mddev->writes_pending,0);
mddev->safemode = 0;
mddev->safemode_timer.function = md_safemode_timeout;
mddev->safemode_timer.data = (unsigned long) mddev;
mddev->safemode_delay = (20 * HZ)/1000 +1; /* 20 msec delay */
mddev->in_sync = 1;
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
if (mddev->sb_dirty)
md_update_sb(mddev);
set_capacity(disk, mddev->array_size<<1);
/* If we call blk_queue_make_request here, it will
* re-initialise max_sectors etc which may have been
* refined inside -> run. So just set the bits we need to set.
* Most initialisation happended when we called
* blk_queue_make_request(..., md_fail_request)
* earlier.
*/
mddev->queue->queuedata = mddev;
mddev->queue->make_request_fn = mddev->pers->make_request;
mddev->changed = 1;
return 0;
}
static int restart_array(mddev_t *mddev)
{
struct gendisk *disk = mddev->gendisk;
int err;
/*
* Complain if it has no devices
*/
err = -ENXIO;
if (list_empty(&mddev->disks))
goto out;
if (mddev->pers) {
err = -EBUSY;
if (!mddev->ro)
goto out;
mddev->safemode = 0;
mddev->ro = 0;
set_disk_ro(disk, 0);
printk(KERN_INFO "md: %s switched to read-write mode.\n",
mdname(mddev));
/*
* Kick recovery or resync if necessary
*/
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
md_wakeup_thread(mddev->thread);
err = 0;
} else {
printk(KERN_ERR "md: %s has no personality assigned.\n",
mdname(mddev));
err = -EINVAL;
}
out:
return err;
}
static int do_md_stop(mddev_t * mddev, int ro)
{
int err = 0;
struct gendisk *disk = mddev->gendisk;
if (mddev->pers) {
if (atomic_read(&mddev->active)>2) {
printk("md: %s still in use.\n",mdname(mddev));
return -EBUSY;
}
if (mddev->sync_thread) {
set_bit(MD_RECOVERY_INTR, &mddev->recovery);
md_unregister_thread(mddev->sync_thread);
mddev->sync_thread = NULL;
}
del_timer_sync(&mddev->safemode_timer);
invalidate_partition(disk, 0);
if (ro) {
err = -ENXIO;
if (mddev->ro)
goto out;
mddev->ro = 1;
} else {
bitmap_flush(mddev);
wait_event(mddev->sb_wait, atomic_read(&mddev->pending_writes)==0);
if (mddev->ro)
set_disk_ro(disk, 0);
blk_queue_make_request(mddev->queue, md_fail_request);
mddev->pers->stop(mddev);
module_put(mddev->pers->owner);
mddev->pers = NULL;
if (mddev->ro)
mddev->ro = 0;
}
if (!mddev->in_sync) {
/* mark array as shutdown cleanly */
mddev->in_sync = 1;
md_update_sb(mddev);
}
if (ro)
set_disk_ro(disk, 1);
}
bitmap_destroy(mddev);
if (mddev->bitmap_file) {
atomic_set(&mddev->bitmap_file->f_dentry->d_inode->i_writecount, 1);
fput(mddev->bitmap_file);
mddev->bitmap_file = NULL;
}
/*
* Free resources if final stop
*/
if (!ro) {
struct gendisk *disk;
printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
export_array(mddev);
mddev->array_size = 0;
disk = mddev->gendisk;
if (disk)
set_capacity(disk, 0);
mddev->changed = 1;
} else
printk(KERN_INFO "md: %s switched to read-only mode.\n",
mdname(mddev));
err = 0;
out:
return err;
}
static void autorun_array(mddev_t *mddev)
{
mdk_rdev_t *rdev;
struct list_head *tmp;
int err;
if (list_empty(&mddev->disks))
return;
printk(KERN_INFO "md: running: ");
ITERATE_RDEV(mddev,rdev,tmp) {
char b[BDEVNAME_SIZE];
printk("<%s>", bdevname(rdev->bdev,b));
}
printk("\n");
err = do_md_run (mddev);
if (err) {
printk(KERN_WARNING "md: do_md_run() returned %d\n", err);
do_md_stop (mddev, 0);
}
}
/*
* lets try to run arrays based on all disks that have arrived
* until now. (those are in pending_raid_disks)
*
* the method: pick the first pending disk, collect all disks with
* the same UUID, remove all from the pending list and put them into
* the 'same_array' list. Then order this list based on superblock
* update time (freshest comes first), kick out 'old' disks and
* compare superblocks. If everything's fine then run it.
*
* If "unit" is allocated, then bump its reference count
*/
static void autorun_devices(int part)
{
struct list_head candidates;
struct list_head *tmp;
mdk_rdev_t *rdev0, *rdev;
mddev_t *mddev;
char b[BDEVNAME_SIZE];
printk(KERN_INFO "md: autorun ...\n");
while (!list_empty(&pending_raid_disks)) {
dev_t dev;
rdev0 = list_entry(pending_raid_disks.next,
mdk_rdev_t, same_set);
printk(KERN_INFO "md: considering %s ...\n",
bdevname(rdev0->bdev,b));
INIT_LIST_HEAD(&candidates);
ITERATE_RDEV_PENDING(rdev,tmp)
if (super_90_load(rdev, rdev0, 0) >= 0) {
printk(KERN_INFO "md: adding %s ...\n",
bdevname(rdev->bdev,b));
list_move(&rdev->same_set, &candidates);
}
/*
* now we have a set of devices, with all of them having
* mostly sane superblocks. It's time to allocate the
* mddev.
*/
if (rdev0->preferred_minor < 0 || rdev0->preferred_minor >= MAX_MD_DEVS) {
printk(KERN_INFO "md: unit number in %s is bad: %d\n",
bdevname(rdev0->bdev, b), rdev0->preferred_minor);
break;
}
if (part)
dev = MKDEV(mdp_major,
rdev0->preferred_minor << MdpMinorShift);
else
dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
md_probe(dev, NULL, NULL);
mddev = mddev_find(dev);
if (!mddev) {
printk(KERN_ERR
"md: cannot allocate memory for md drive.\n");
break;
}
if (mddev_lock(mddev))
printk(KERN_WARNING "md: %s locked, cannot run\n",
mdname(mddev));
else if (mddev->raid_disks || mddev->major_version
|| !list_empty(&mddev->disks)) {
printk(KERN_WARNING
"md: %s already running, cannot run %s\n",
mdname(mddev), bdevname(rdev0->bdev,b));
mddev_unlock(mddev);
} else {
printk(KERN_INFO "md: created %s\n", mdname(mddev));
ITERATE_RDEV_GENERIC(candidates,rdev,tmp) {
list_del_init(&rdev->same_set);
if (bind_rdev_to_array(rdev, mddev))
export_rdev(rdev);
}
autorun_array(mddev);
mddev_unlock(mddev);
}
/* on success, candidates will be empty, on error
* it won't...
*/
ITERATE_RDEV_GENERIC(candidates,rdev,tmp)
export_rdev(rdev);
mddev_put(mddev);
}
printk(KERN_INFO "md: ... autorun DONE.\n");
}
/*
* import RAID devices based on one partition
* if possible, the array gets run as well.
*/
static int autostart_array(dev_t startdev)
{
char b[BDEVNAME_SIZE];
int err = -EINVAL, i;
mdp_super_t *sb = NULL;
mdk_rdev_t *start_rdev = NULL, *rdev;
start_rdev = md_import_device(startdev, 0, 0);
if (IS_ERR(start_rdev))
return err;
/* NOTE: this can only work for 0.90.0 superblocks */
sb = (mdp_super_t*)page_address(start_rdev->sb_page);
if (sb->major_version != 0 ||
sb->minor_version != 90 ) {
printk(KERN_WARNING "md: can only autostart 0.90.0 arrays\n");
export_rdev(start_rdev);
return err;
}
if (start_rdev->faulty) {
printk(KERN_WARNING
"md: can not autostart based on faulty %s!\n",
bdevname(start_rdev->bdev,b));
export_rdev(start_rdev);
return err;
}
list_add(&start_rdev->same_set, &pending_raid_disks);
for (i = 0; i < MD_SB_DISKS; i++) {
mdp_disk_t *desc = sb->disks + i;
dev_t dev = MKDEV(desc->major, desc->minor);
if (!dev)
continue;
if (dev == startdev)
continue;
if (MAJOR(dev) != desc->major || MINOR(dev) != desc->minor)
continue;
rdev = md_import_device(dev, 0, 0);
if (IS_ERR(rdev))
continue;
list_add(&rdev->same_set, &pending_raid_disks);
}
/*
* possibly return codes
*/
autorun_devices(0);
return 0;
}
static int get_version(void __user * arg)
{
mdu_version_t ver;
ver.major = MD_MAJOR_VERSION;
ver.minor = MD_MINOR_VERSION;
ver.patchlevel = MD_PATCHLEVEL_VERSION;
if (copy_to_user(arg, &ver, sizeof(ver)))
return -EFAULT;
return 0;
}
static int get_array_info(mddev_t * mddev, void __user * arg)
{
mdu_array_info_t info;
int nr,working,active,failed,spare;
mdk_rdev_t *rdev;
struct list_head *tmp;
nr=working=active=failed=spare=0;
ITERATE_RDEV(mddev,rdev,tmp) {
nr++;
if (rdev->faulty)
failed++;
else {
working++;
if (rdev->in_sync)
active++;
else
spare++;
}
}
info.major_version = mddev->major_version;
info.minor_version = mddev->minor_version;
info.patch_version = MD_PATCHLEVEL_VERSION;
info.ctime = mddev->ctime;
info.level = mddev->level;
info.size = mddev->size;
info.nr_disks = nr;
info.raid_disks = mddev->raid_disks;
info.md_minor = mddev->md_minor;
info.not_persistent= !mddev->persistent;
info.utime = mddev->utime;
info.state = 0;
if (mddev->in_sync)
info.state = (1<<MD_SB_CLEAN);
info.active_disks = active;
info.working_disks = working;
info.failed_disks = failed;
info.spare_disks = spare;
info.layout = mddev->layout;
info.chunk_size = mddev->chunk_size;
if (copy_to_user(arg, &info, sizeof(info)))
return -EFAULT;
return 0;
}
static int get_bitmap_file(mddev_t * mddev, void * arg)
{
mdu_bitmap_file_t *file = NULL; /* too big for stack allocation */
char *ptr, *buf = NULL;
int err = -ENOMEM;
file = kmalloc(sizeof(*file), GFP_KERNEL);
if (!file)
goto out;
/* bitmap disabled, zero the first byte and copy out */
if (!mddev->bitmap || !mddev->bitmap->file) {
file->pathname[0] = '\0';
goto copy_out;
}
buf = kmalloc(sizeof(file->pathname), GFP_KERNEL);
if (!buf)
goto out;
ptr = file_path(mddev->bitmap->file, buf, sizeof(file->pathname));
if (!ptr)
goto out;
strcpy(file->pathname, ptr);
copy_out:
err = 0;
if (copy_to_user(arg, file, sizeof(*file)))
err = -EFAULT;
out:
kfree(buf);
kfree(file);
return err;
}
static int get_disk_info(mddev_t * mddev, void __user * arg)
{
mdu_disk_info_t info;
unsigned int nr;
mdk_rdev_t *rdev;
if (copy_from_user(&info, arg, sizeof(info)))
return -EFAULT;
nr = info.number;
rdev = find_rdev_nr(mddev, nr);
if (rdev) {
info.major = MAJOR(rdev->bdev->bd_dev);
info.minor = MINOR(rdev->bdev->bd_dev);
info.raid_disk = rdev->raid_disk;
info.state = 0;
if (rdev->faulty)
info.state |= (1<<MD_DISK_FAULTY);
else if (rdev->in_sync) {
info.state |= (1<<MD_DISK_ACTIVE);
info.state |= (1<<MD_DISK_SYNC);
}
} else {
info.major = info.minor = 0;
info.raid_disk = -1;
info.state = (1<<MD_DISK_REMOVED);
}
if (copy_to_user(arg, &info, sizeof(info)))
return -EFAULT;
return 0;
}
static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info)
{
char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
mdk_rdev_t *rdev;
dev_t dev = MKDEV(info->major,info->minor);
if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
return -EOVERFLOW;
if (!mddev->raid_disks) {
int err;
/* expecting a device which has a superblock */
rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
if (IS_ERR(rdev)) {
printk(KERN_WARNING
"md: md_import_device returned %ld\n",
PTR_ERR(rdev));
return PTR_ERR(rdev);
}
if (!list_empty(&mddev->disks)) {
mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
mdk_rdev_t, same_set);
int err = super_types[mddev->major_version]
.load_super(rdev, rdev0, mddev->minor_version);
if (err < 0) {
printk(KERN_WARNING
"md: %s has different UUID to %s\n",
bdevname(rdev->bdev,b),
bdevname(rdev0->bdev,b2));
export_rdev(rdev);
return -EINVAL;
}
}
err = bind_rdev_to_array(rdev, mddev);
if (err)
export_rdev(rdev);
return err;
}
/*
* add_new_disk can be used once the array is assembled
* to add "hot spares". They must already have a superblock
* written
*/
if (mddev->pers) {
int err;
if (!mddev->pers->hot_add_disk) {
printk(KERN_WARNING
"%s: personality does not support diskops!\n",
mdname(mddev));
return -EINVAL;
}
rdev = md_import_device(dev, mddev->major_version,
mddev->minor_version);
if (IS_ERR(rdev)) {
printk(KERN_WARNING
"md: md_import_device returned %ld\n",
PTR_ERR(rdev));
return PTR_ERR(rdev);
}
/* set save_raid_disk if appropriate */
if (!mddev->persistent) {
if (info->state & (1<<MD_DISK_SYNC) &&
info->raid_disk < mddev->raid_disks)
rdev->raid_disk = info->raid_disk;
else
rdev->raid_disk = -1;
} else
super_types[mddev->major_version].
validate_super(mddev, rdev);
rdev->saved_raid_disk = rdev->raid_disk;
rdev->in_sync = 0; /* just to be sure */
rdev->raid_disk = -1;
err = bind_rdev_to_array(rdev, mddev);
if (err)
export_rdev(rdev);
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
if (mddev->thread)
md_wakeup_thread(mddev->thread);
return err;
}
/* otherwise, add_new_disk is only allowed
* for major_version==0 superblocks
*/
if (mddev->major_version != 0) {
printk(KERN_WARNING "%s: ADD_NEW_DISK not supported\n",
mdname(mddev));
return -EINVAL;
}
if (!(info->state & (1<<MD_DISK_FAULTY))) {
int err;
rdev = md_import_device (dev, -1, 0);
if (IS_ERR(rdev)) {
printk(KERN_WARNING
"md: error, md_import_device() returned %ld\n",
PTR_ERR(rdev));
return PTR_ERR(rdev);
}
rdev->desc_nr = info->number;
if (info->raid_disk < mddev->raid_disks)
rdev->raid_disk = info->raid_disk;
else
rdev->raid_disk = -1;
rdev->faulty = 0;
if (rdev->raid_disk < mddev->raid_disks)
rdev->in_sync = (info->state & (1<<MD_DISK_SYNC));
else
rdev->in_sync = 0;
err = bind_rdev_to_array(rdev, mddev);
if (err) {
export_rdev(rdev);
return err;
}
if (!mddev->persistent) {
printk(KERN_INFO "md: nonpersistent superblock ...\n");
rdev->sb_offset = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
} else
rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
rdev->size = calc_dev_size(rdev, mddev->chunk_size);
if (!mddev->size || (mddev->size > rdev->size))
mddev->size = rdev->size;
}
return 0;
}
static int hot_remove_disk(mddev_t * mddev, dev_t dev)
{
char b[BDEVNAME_SIZE];
mdk_rdev_t *rdev;
if (!mddev->pers)
return -ENODEV;
rdev = find_rdev(mddev, dev);
if (!rdev)
return -ENXIO;
if (rdev->raid_disk >= 0)
goto busy;
kick_rdev_from_array(rdev);
md_update_sb(mddev);
return 0;
busy:
printk(KERN_WARNING "md: cannot remove active disk %s from %s ... \n",
bdevname(rdev->bdev,b), mdname(mddev));
return -EBUSY;
}
static int hot_add_disk(mddev_t * mddev, dev_t dev)
{
char b[BDEVNAME_SIZE];
int err;
unsigned int size;
mdk_rdev_t *rdev;
if (!mddev->pers)
return -ENODEV;
if (mddev->major_version != 0) {
printk(KERN_WARNING "%s: HOT_ADD may only be used with"
" version-0 superblocks.\n",
mdname(mddev));
return -EINVAL;
}
if (!mddev->pers->hot_add_disk) {
printk(KERN_WARNING
"%s: personality does not support diskops!\n",
mdname(mddev));
return -EINVAL;
}
rdev = md_import_device (dev, -1, 0);
if (IS_ERR(rdev)) {
printk(KERN_WARNING
"md: error, md_import_device() returned %ld\n",
PTR_ERR(rdev));
return -EINVAL;
}
if (mddev->persistent)
rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
else
rdev->sb_offset =
rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
size = calc_dev_size(rdev, mddev->chunk_size);
rdev->size = size;
if (size < mddev->size) {
printk(KERN_WARNING
"%s: disk size %llu blocks < array size %llu\n",
mdname(mddev), (unsigned long long)size,
(unsigned long long)mddev->size);
err = -ENOSPC;
goto abort_export;
}
if (rdev->faulty) {
printk(KERN_WARNING
"md: can not hot-add faulty %s disk to %s!\n",
bdevname(rdev->bdev,b), mdname(mddev));
err = -EINVAL;
goto abort_export;
}
rdev->in_sync = 0;
rdev->desc_nr = -1;
bind_rdev_to_array(rdev, mddev);
/*
* The rest should better be atomic, we can have disk failures
* noticed in interrupt contexts ...
*/
if (rdev->desc_nr == mddev->max_disks) {
printk(KERN_WARNING "%s: can not hot-add to full array!\n",
mdname(mddev));
err = -EBUSY;
goto abort_unbind_export;
}
rdev->raid_disk = -1;
md_update_sb(mddev);
/*
* Kick recovery, maybe this spare has to be added to the
* array immediately.
*/
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
md_wakeup_thread(mddev->thread);
return 0;
abort_unbind_export:
unbind_rdev_from_array(rdev);
abort_export:
export_rdev(rdev);
return err;
}
/* similar to deny_write_access, but accounts for our holding a reference
* to the file ourselves */
static int deny_bitmap_write_access(struct file * file)
{
struct inode *inode = file->f_mapping->host;
spin_lock(&inode->i_lock);
if (atomic_read(&inode->i_writecount) > 1) {
spin_unlock(&inode->i_lock);
return -ETXTBSY;
}
atomic_set(&inode->i_writecount, -1);
spin_unlock(&inode->i_lock);
return 0;
}
static int set_bitmap_file(mddev_t *mddev, int fd)
{
int err;
if (mddev->pers)
return -EBUSY;
mddev->bitmap_file = fget(fd);
if (mddev->bitmap_file == NULL) {
printk(KERN_ERR "%s: error: failed to get bitmap file\n",
mdname(mddev));
return -EBADF;
}
err = deny_bitmap_write_access(mddev->bitmap_file);
if (err) {
printk(KERN_ERR "%s: error: bitmap file is already in use\n",
mdname(mddev));
fput(mddev->bitmap_file);
mddev->bitmap_file = NULL;
} else
mddev->bitmap_offset = 0; /* file overrides offset */
return err;
}
/*
* set_array_info is used two different ways
* The original usage is when creating a new array.
* In this usage, raid_disks is > 0 and it together with
* level, size, not_persistent,layout,chunksize determine the
* shape of the array.
* This will always create an array with a type-0.90.0 superblock.
* The newer usage is when assembling an array.
* In this case raid_disks will be 0, and the major_version field is
* use to determine which style super-blocks are to be found on the devices.
* The minor and patch _version numbers are also kept incase the
* super_block handler wishes to interpret them.
*/
static int set_array_info(mddev_t * mddev, mdu_array_info_t *info)
{
if (info->raid_disks == 0) {
/* just setting version number for superblock loading */
if (info->major_version < 0 ||
info->major_version >= sizeof(super_types)/sizeof(super_types[0]) ||
super_types[info->major_version].name == NULL) {
/* maybe try to auto-load a module? */
printk(KERN_INFO
"md: superblock version %d not known\n",
info->major_version);
return -EINVAL;
}
mddev->major_version = info->major_version;
mddev->minor_version = info->minor_version;
mddev->patch_version = info->patch_version;
return 0;
}
mddev->major_version = MD_MAJOR_VERSION;
mddev->minor_version = MD_MINOR_VERSION;
mddev->patch_version = MD_PATCHLEVEL_VERSION;
mddev->ctime = get_seconds();
mddev->level = info->level;
mddev->size = info->size;
mddev->raid_disks = info->raid_disks;
/* don't set md_minor, it is determined by which /dev/md* was
* openned
*/
if (info->state & (1<<MD_SB_CLEAN))
mddev->recovery_cp = MaxSector;
else
mddev->recovery_cp = 0;
mddev->persistent = ! info->not_persistent;
mddev->layout = info->layout;
mddev->chunk_size = info->chunk_size;
mddev->max_disks = MD_SB_DISKS;
mddev->sb_dirty = 1;
/*
* Generate a 128 bit UUID
*/
get_random_bytes(mddev->uuid, 16);
return 0;
}
/*
* update_array_info is used to change the configuration of an
* on-line array.
* The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
* fields in the info are checked against the array.
* Any differences that cannot be handled will cause an error.
* Normally, only one change can be managed at a time.
*/
static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
{
int rv = 0;
int cnt = 0;
if (mddev->major_version != info->major_version ||
mddev->minor_version != info->minor_version ||
/* mddev->patch_version != info->patch_version || */
mddev->ctime != info->ctime ||
mddev->level != info->level ||
/* mddev->layout != info->layout || */
!mddev->persistent != info->not_persistent||
mddev->chunk_size != info->chunk_size )
return -EINVAL;
/* Check there is only one change */
if (mddev->size != info->size) cnt++;
if (mddev->raid_disks != info->raid_disks) cnt++;
if (mddev->layout != info->layout) cnt++;
if (cnt == 0) return 0;
if (cnt > 1) return -EINVAL;
if (mddev->layout != info->layout) {
/* Change layout
* we don't need to do anything at the md level, the
* personality will take care of it all.
*/
if (mddev->pers->reconfig == NULL)
return -EINVAL;
else
return mddev->pers->reconfig(mddev, info->layout, -1);
}
if (mddev->size != info->size) {
mdk_rdev_t * rdev;
struct list_head *tmp;
if (mddev->pers->resize == NULL)
return -EINVAL;
/* The "size" is the amount of each device that is used.
* This can only make sense for arrays with redundancy.
* linear and raid0 always use whatever space is available
* We can only consider changing the size if no resync
* or reconstruction is happening, and if the new size
* is acceptable. It must fit before the sb_offset or,
* if that is <data_offset, it must fit before the
* size of each device.
* If size is zero, we find the largest size that fits.
*/
if (mddev->sync_thread)
return -EBUSY;
ITERATE_RDEV(mddev,rdev,tmp) {
sector_t avail;
int fit = (info->size == 0);
if (rdev->sb_offset > rdev->data_offset)
avail = (rdev->sb_offset*2) - rdev->data_offset;
else
avail = get_capacity(rdev->bdev->bd_disk)
- rdev->data_offset;
if (fit && (info->size == 0 || info->size > avail/2))
info->size = avail/2;
if (avail < ((sector_t)info->size << 1))
return -ENOSPC;
}
rv = mddev->pers->resize(mddev, (sector_t)info->size *2);
if (!rv) {
struct block_device *bdev;
bdev = bdget_disk(mddev->gendisk, 0);
if (bdev) {
down(&bdev->bd_inode->i_sem);
i_size_write(bdev->bd_inode, mddev->array_size << 10);
up(&bdev->bd_inode->i_sem);
bdput(bdev);
}
}
}
if (mddev->raid_disks != info->raid_disks) {
/* change the number of raid disks */
if (mddev->pers->reshape == NULL)
return -EINVAL;
if (info->raid_disks <= 0 ||
info->raid_disks >= mddev->max_disks)
return -EINVAL;
if (mddev->sync_thread)
return -EBUSY;
rv = mddev->pers->reshape(mddev, info->raid_disks);
if (!rv) {
struct block_device *bdev;
bdev = bdget_disk(mddev->gendisk, 0);
if (bdev) {
down(&bdev->bd_inode->i_sem);
i_size_write(bdev->bd_inode, mddev->array_size << 10);
up(&bdev->bd_inode->i_sem);
bdput(bdev);
}
}
}
md_update_sb(mddev);
return rv;
}
static int set_disk_faulty(mddev_t *mddev, dev_t dev)
{
mdk_rdev_t *rdev;
if (mddev->pers == NULL)
return -ENODEV;
rdev = find_rdev(mddev, dev);
if (!rdev)
return -ENODEV;
md_error(mddev, rdev);
return 0;
}
static int md_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
{
int err = 0;
void __user *argp = (void __user *)arg;
struct hd_geometry __user *loc = argp;
mddev_t *mddev = NULL;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
/*
* Commands dealing with the RAID driver but not any
* particular array:
*/
switch (cmd)
{
case RAID_VERSION:
err = get_version(argp);
goto done;
case PRINT_RAID_DEBUG:
err = 0;
md_print_devices();
goto done;
#ifndef MODULE
case RAID_AUTORUN:
err = 0;
autostart_arrays(arg);
goto done;
#endif
default:;
}
/*
* Commands creating/starting a new array:
*/
mddev = inode->i_bdev->bd_disk->private_data;
if (!mddev) {
BUG();
goto abort;
}
if (cmd == START_ARRAY) {
/* START_ARRAY doesn't need to lock the array as autostart_array
* does the locking, and it could even be a different array
*/
static int cnt = 3;
if (cnt > 0 ) {
printk(KERN_WARNING
"md: %s(pid %d) used deprecated START_ARRAY ioctl. "
"This will not be supported beyond 2.6\n",
current->comm, current->pid);
cnt--;
}
err = autostart_array(new_decode_dev(arg));
if (err) {
printk(KERN_WARNING "md: autostart failed!\n");
goto abort;
}
goto done;
}
err = mddev_lock(mddev);
if (err) {
printk(KERN_INFO
"md: ioctl lock interrupted, reason %d, cmd %d\n",
err, cmd);
goto abort;
}
switch (cmd)
{
case SET_ARRAY_INFO:
{
mdu_array_info_t info;
if (!arg)
memset(&info, 0, sizeof(info));
else if (copy_from_user(&info, argp, sizeof(info))) {
err = -EFAULT;
goto abort_unlock;
}
if (mddev->pers) {
err = update_array_info(mddev, &info);
if (err) {
printk(KERN_WARNING "md: couldn't update"
" array info. %d\n", err);
goto abort_unlock;
}
goto done_unlock;
}
if (!list_empty(&mddev->disks)) {
printk(KERN_WARNING
"md: array %s already has disks!\n",
mdname(mddev));
err = -EBUSY;
goto abort_unlock;
}
if (mddev->raid_disks) {
printk(KERN_WARNING
"md: array %s already initialised!\n",
mdname(mddev));
err = -EBUSY;
goto abort_unlock;
}
err = set_array_info(mddev, &info);
if (err) {
printk(KERN_WARNING "md: couldn't set"
" array info. %d\n", err);
goto abort_unlock;
}
}
goto done_unlock;
default:;
}
/*
* Commands querying/configuring an existing array:
*/
/* if we are not initialised yet, only ADD_NEW_DISK, STOP_ARRAY,
* RUN_ARRAY, and SET_BITMAP_FILE are allowed */
if (!mddev->raid_disks && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY
&& cmd != RUN_ARRAY && cmd != SET_BITMAP_FILE) {
err = -ENODEV;
goto abort_unlock;
}
/*
* Commands even a read-only array can execute:
*/
switch (cmd)
{
case GET_ARRAY_INFO:
err = get_array_info(mddev, argp);
goto done_unlock;
case GET_BITMAP_FILE:
err = get_bitmap_file(mddev, (void *)arg);
goto done_unlock;
case GET_DISK_INFO:
err = get_disk_info(mddev, argp);
goto done_unlock;
case RESTART_ARRAY_RW:
err = restart_array(mddev);
goto done_unlock;
case STOP_ARRAY:
err = do_md_stop (mddev, 0);
goto done_unlock;
case STOP_ARRAY_RO:
err = do_md_stop (mddev, 1);
goto done_unlock;
/*
* We have a problem here : there is no easy way to give a CHS
* virtual geometry. We currently pretend that we have a 2 heads
* 4 sectors (with a BIG number of cylinders...). This drives
* dosfs just mad... ;-)
*/
case HDIO_GETGEO:
if (!loc) {
err = -EINVAL;
goto abort_unlock;
}
err = put_user (2, (char __user *) &loc->heads);
if (err)
goto abort_unlock;
err = put_user (4, (char __user *) &loc->sectors);
if (err)
goto abort_unlock;
err = put_user(get_capacity(mddev->gendisk)/8,
(short __user *) &loc->cylinders);
if (err)
goto abort_unlock;
err = put_user (get_start_sect(inode->i_bdev),
(long __user *) &loc->start);
goto done_unlock;
}
/*
* The remaining ioctls are changing the state of the
* superblock, so we do not allow read-only arrays
* here:
*/
if (mddev->ro) {
err = -EROFS;
goto abort_unlock;
}
switch (cmd)
{
case ADD_NEW_DISK:
{
mdu_disk_info_t info;
if (copy_from_user(&info, argp, sizeof(info)))
err = -EFAULT;
else
err = add_new_disk(mddev, &info);
goto done_unlock;
}
case HOT_REMOVE_DISK:
err = hot_remove_disk(mddev, new_decode_dev(arg));
goto done_unlock;
case HOT_ADD_DISK:
err = hot_add_disk(mddev, new_decode_dev(arg));
goto done_unlock;
case SET_DISK_FAULTY:
err = set_disk_faulty(mddev, new_decode_dev(arg));
goto done_unlock;
case RUN_ARRAY:
err = do_md_run (mddev);
goto done_unlock;
case SET_BITMAP_FILE:
err = set_bitmap_file(mddev, (int)arg);
goto done_unlock;
default:
if (_IOC_TYPE(cmd) == MD_MAJOR)
printk(KERN_WARNING "md: %s(pid %d) used"
" obsolete MD ioctl, upgrade your"
" software to use new ictls.\n",
current->comm, current->pid);
err = -EINVAL;
goto abort_unlock;
}
done_unlock:
abort_unlock:
mddev_unlock(mddev);
return err;
done:
if (err)
MD_BUG();
abort:
return err;
}
static int md_open(struct inode *inode, struct file *file)
{
/*
* Succeed if we can lock the mddev, which confirms that
* it isn't being stopped right now.
*/
mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
int err;
if ((err = mddev_lock(mddev)))
goto out;
err = 0;
mddev_get(mddev);
mddev_unlock(mddev);
check_disk_change(inode->i_bdev);
out:
return err;
}
static int md_release(struct inode *inode, struct file * file)
{
mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
if (!mddev)
BUG();
mddev_put(mddev);
return 0;
}
static int md_media_changed(struct gendisk *disk)
{
mddev_t *mddev = disk->private_data;
return mddev->changed;
}
static int md_revalidate(struct gendisk *disk)
{
mddev_t *mddev = disk->private_data;
mddev->changed = 0;
return 0;
}
static struct block_device_operations md_fops =
{
.owner = THIS_MODULE,
.open = md_open,
.release = md_release,
.ioctl = md_ioctl,
.media_changed = md_media_changed,
.revalidate_disk= md_revalidate,
};
static int md_thread(void * arg)
{
mdk_thread_t *thread = arg;
lock_kernel();
/*
* Detach thread
*/
daemonize(thread->name, mdname(thread->mddev));
current->exit_signal = SIGCHLD;
allow_signal(SIGKILL);
thread->tsk = current;
/*
* md_thread is a 'system-thread', it's priority should be very
* high. We avoid resource deadlocks individually in each
* raid personality. (RAID5 does preallocation) We also use RR and
* the very same RT priority as kswapd, thus we will never get
* into a priority inversion deadlock.
*
* we definitely have to have equal or higher priority than
* bdflush, otherwise bdflush will deadlock if there are too
* many dirty RAID5 blocks.
*/
unlock_kernel();
complete(thread->event);
while (thread->run) {
void (*run)(mddev_t *);
wait_event_interruptible_timeout(thread->wqueue,
test_bit(THREAD_WAKEUP, &thread->flags),
thread->timeout);
try_to_freeze();
clear_bit(THREAD_WAKEUP, &thread->flags);
run = thread->run;
if (run)
run(thread->mddev);
if (signal_pending(current))
flush_signals(current);
}
complete(thread->event);
return 0;
}
void md_wakeup_thread(mdk_thread_t *thread)
{
if (thread) {
dprintk("md: waking up MD thread %s.\n", thread->tsk->comm);
set_bit(THREAD_WAKEUP, &thread->flags);
wake_up(&thread->wqueue);
}
}
mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev,
const char *name)
{
mdk_thread_t *thread;
int ret;
struct completion event;
thread = (mdk_thread_t *) kmalloc
(sizeof(mdk_thread_t), GFP_KERNEL);
if (!thread)
return NULL;
memset(thread, 0, sizeof(mdk_thread_t));
init_waitqueue_head(&thread->wqueue);
init_completion(&event);
thread->event = &event;
thread->run = run;
thread->mddev = mddev;
thread->name = name;
thread->timeout = MAX_SCHEDULE_TIMEOUT;
ret = kernel_thread(md_thread, thread, 0);
if (ret < 0) {
kfree(thread);
return NULL;
}
wait_for_completion(&event);
return thread;
}
void md_unregister_thread(mdk_thread_t *thread)
{
struct completion event;
init_completion(&event);
thread->event = &event;
/* As soon as ->run is set to NULL, the task could disappear,
* so we need to hold tasklist_lock until we have sent the signal
*/
dprintk("interrupting MD-thread pid %d\n", thread->tsk->pid);
read_lock(&tasklist_lock);
thread->run = NULL;
send_sig(SIGKILL, thread->tsk, 1);
read_unlock(&tasklist_lock);
wait_for_completion(&event);
kfree(thread);
}
void md_error(mddev_t *mddev, mdk_rdev_t *rdev)
{
if (!mddev) {
MD_BUG();
return;
}
if (!rdev || rdev->faulty)
return;
/*
dprintk("md_error dev:%s, rdev:(%d:%d), (caller: %p,%p,%p,%p).\n",
mdname(mddev),
MAJOR(rdev->bdev->bd_dev), MINOR(rdev->bdev->bd_dev),
__builtin_return_address(0),__builtin_return_address(1),
__builtin_return_address(2),__builtin_return_address(3));
*/
if (!mddev->pers->error_handler)
return;
mddev->pers->error_handler(mddev,rdev);
set_bit(MD_RECOVERY_INTR, &mddev->recovery);
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
md_wakeup_thread(mddev->thread);
}
/* seq_file implementation /proc/mdstat */
static void status_unused(struct seq_file *seq)
{
int i = 0;
mdk_rdev_t *rdev;
struct list_head *tmp;
seq_printf(seq, "unused devices: ");
ITERATE_RDEV_PENDING(rdev,tmp) {
char b[BDEVNAME_SIZE];
i++;
seq_printf(seq, "%s ",
bdevname(rdev->bdev,b));
}
if (!i)
seq_printf(seq, "<none>");
seq_printf(seq, "\n");
}
static void status_resync(struct seq_file *seq, mddev_t * mddev)
{
unsigned long max_blocks, resync, res, dt, db, rt;
resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active))/2;
if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
max_blocks = mddev->resync_max_sectors >> 1;
else
max_blocks = mddev->size;
/*
* Should not happen.
*/
if (!max_blocks) {
MD_BUG();
return;
}
res = (resync/1024)*1000/(max_blocks/1024 + 1);
{
int i, x = res/50, y = 20-x;
seq_printf(seq, "[");
for (i = 0; i < x; i++)
seq_printf(seq, "=");
seq_printf(seq, ">");
for (i = 0; i < y; i++)
seq_printf(seq, ".");
seq_printf(seq, "] ");
}
seq_printf(seq, " %s =%3lu.%lu%% (%lu/%lu)",
(test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
"resync" : "recovery"),
res/10, res % 10, resync, max_blocks);
/*
* We do not want to overflow, so the order of operands and
* the * 100 / 100 trick are important. We do a +1 to be
* safe against division by zero. We only estimate anyway.
*
* dt: time from mark until now
* db: blocks written from mark until now
* rt: remaining time
*/
dt = ((jiffies - mddev->resync_mark) / HZ);
if (!dt) dt++;
db = resync - (mddev->resync_mark_cnt/2);
rt = (dt * ((max_blocks-resync) / (db/100+1)))/100;
seq_printf(seq, " finish=%lu.%lumin", rt / 60, (rt % 60)/6);
seq_printf(seq, " speed=%ldK/sec", db/dt);
}
static void *md_seq_start(struct seq_file *seq, loff_t *pos)
{
struct list_head *tmp;
loff_t l = *pos;
mddev_t *mddev;
if (l >= 0x10000)
return NULL;
if (!l--)
/* header */
return (void*)1;
spin_lock(&all_mddevs_lock);
list_for_each(tmp,&all_mddevs)
if (!l--) {
mddev = list_entry(tmp, mddev_t, all_mddevs);
mddev_get(mddev);
spin_unlock(&all_mddevs_lock);
return mddev;
}
spin_unlock(&all_mddevs_lock);
if (!l--)
return (void*)2;/* tail */
return NULL;
}
static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct list_head *tmp;
mddev_t *next_mddev, *mddev = v;
++*pos;
if (v == (void*)2)
return NULL;
spin_lock(&all_mddevs_lock);
if (v == (void*)1)
tmp = all_mddevs.next;
else
tmp = mddev->all_mddevs.next;
if (tmp != &all_mddevs)
next_mddev = mddev_get(list_entry(tmp,mddev_t,all_mddevs));
else {
next_mddev = (void*)2;
*pos = 0x10000;
}
spin_unlock(&all_mddevs_lock);
if (v != (void*)1)
mddev_put(mddev);
return next_mddev;
}
static void md_seq_stop(struct seq_file *seq, void *v)
{
mddev_t *mddev = v;
if (mddev && v != (void*)1 && v != (void*)2)
mddev_put(mddev);
}
static int md_seq_show(struct seq_file *seq, void *v)
{
mddev_t *mddev = v;
sector_t size;
struct list_head *tmp2;
mdk_rdev_t *rdev;
int i;
struct bitmap *bitmap;
if (v == (void*)1) {
seq_printf(seq, "Personalities : ");
spin_lock(&pers_lock);
for (i = 0; i < MAX_PERSONALITY; i++)
if (pers[i])
seq_printf(seq, "[%s] ", pers[i]->name);
spin_unlock(&pers_lock);
seq_printf(seq, "\n");
return 0;
}
if (v == (void*)2) {
status_unused(seq);
return 0;
}
if (mddev_lock(mddev)!=0)
return -EINTR;
if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
seq_printf(seq, "%s : %sactive", mdname(mddev),
mddev->pers ? "" : "in");
if (mddev->pers) {
if (mddev->ro)
seq_printf(seq, " (read-only)");
seq_printf(seq, " %s", mddev->pers->name);
}
size = 0;
ITERATE_RDEV(mddev,rdev,tmp2) {
char b[BDEVNAME_SIZE];
seq_printf(seq, " %s[%d]",
bdevname(rdev->bdev,b), rdev->desc_nr);
if (rdev->faulty) {
seq_printf(seq, "(F)");
continue;
}
size += rdev->size;
}
if (!list_empty(&mddev->disks)) {
if (mddev->pers)
seq_printf(seq, "\n %llu blocks",
(unsigned long long)mddev->array_size);
else
seq_printf(seq, "\n %llu blocks",
(unsigned long long)size);
}
if (mddev->pers) {
mddev->pers->status (seq, mddev);
seq_printf(seq, "\n ");
if (mddev->curr_resync > 2) {
status_resync (seq, mddev);
seq_printf(seq, "\n ");
} else if (mddev->curr_resync == 1 || mddev->curr_resync == 2)
seq_printf(seq, " resync=DELAYED\n ");
} else
seq_printf(seq, "\n ");
if ((bitmap = mddev->bitmap)) {
unsigned long chunk_kb;
unsigned long flags;
spin_lock_irqsave(&bitmap->lock, flags);
chunk_kb = bitmap->chunksize >> 10;
seq_printf(seq, "bitmap: %lu/%lu pages [%luKB], "
"%lu%s chunk",
bitmap->pages - bitmap->missing_pages,
bitmap->pages,
(bitmap->pages - bitmap->missing_pages)
<< (PAGE_SHIFT - 10),
chunk_kb ? chunk_kb : bitmap->chunksize,
chunk_kb ? "KB" : "B");
if (bitmap->file) {
seq_printf(seq, ", file: ");
seq_path(seq, bitmap->file->f_vfsmnt,
bitmap->file->f_dentry," \t\n");
}
seq_printf(seq, "\n");
spin_unlock_irqrestore(&bitmap->lock, flags);
}
seq_printf(seq, "\n");
}
mddev_unlock(mddev);
return 0;
}
static struct seq_operations md_seq_ops = {
.start = md_seq_start,
.next = md_seq_next,
.stop = md_seq_stop,
.show = md_seq_show,
};
static int md_seq_open(struct inode *inode, struct file *file)
{
int error;
error = seq_open(file, &md_seq_ops);
return error;
}
static struct file_operations md_seq_fops = {
.open = md_seq_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
int register_md_personality(int pnum, mdk_personality_t *p)
{
if (pnum >= MAX_PERSONALITY) {
printk(KERN_ERR
"md: tried to install personality %s as nr %d, but max is %lu\n",
p->name, pnum, MAX_PERSONALITY-1);
return -EINVAL;
}
spin_lock(&pers_lock);
if (pers[pnum]) {
spin_unlock(&pers_lock);
return -EBUSY;
}
pers[pnum] = p;
printk(KERN_INFO "md: %s personality registered as nr %d\n", p->name, pnum);
spin_unlock(&pers_lock);
return 0;
}
int unregister_md_personality(int pnum)
{
if (pnum >= MAX_PERSONALITY)
return -EINVAL;
printk(KERN_INFO "md: %s personality unregistered\n", pers[pnum]->name);
spin_lock(&pers_lock);
pers[pnum] = NULL;
spin_unlock(&pers_lock);
return 0;
}
static int is_mddev_idle(mddev_t *mddev)
{
mdk_rdev_t * rdev;
struct list_head *tmp;
int idle;
unsigned long curr_events;
idle = 1;
ITERATE_RDEV(mddev,rdev,tmp) {
struct gendisk *disk = rdev->bdev->bd_contains->bd_disk;
curr_events = disk_stat_read(disk, read_sectors) +
disk_stat_read(disk, write_sectors) -
atomic_read(&disk->sync_io);
/* Allow some slack between valud of curr_events and last_events,
* as there are some uninteresting races.
* Note: the following is an unsigned comparison.
*/
if ((curr_events - rdev->last_events + 32) > 64) {
rdev->last_events = curr_events;
idle = 0;
}
}
return idle;
}
void md_done_sync(mddev_t *mddev, int blocks, int ok)
{
/* another "blocks" (512byte) blocks have been synced */
atomic_sub(blocks, &mddev->recovery_active);
wake_up(&mddev->recovery_wait);
if (!ok) {
set_bit(MD_RECOVERY_ERR, &mddev->recovery);
md_wakeup_thread(mddev->thread);
// stop recovery, signal do_sync ....
}
}
/* md_write_start(mddev, bi)
* If we need to update some array metadata (e.g. 'active' flag
* in superblock) before writing, schedule a superblock update
* and wait for it to complete.
*/
void md_write_start(mddev_t *mddev, struct bio *bi)
{
DEFINE_WAIT(w);
if (bio_data_dir(bi) != WRITE)
return;
atomic_inc(&mddev->writes_pending);
if (mddev->in_sync) {
spin_lock(&mddev->write_lock);
if (mddev->in_sync) {
mddev->in_sync = 0;
mddev->sb_dirty = 1;
md_wakeup_thread(mddev->thread);
}
spin_unlock(&mddev->write_lock);
}
wait_event(mddev->sb_wait, mddev->sb_dirty==0);
}
void md_write_end(mddev_t *mddev)
{
if (atomic_dec_and_test(&mddev->writes_pending)) {
if (mddev->safemode == 2)
md_wakeup_thread(mddev->thread);
else
mod_timer(&mddev->safemode_timer, jiffies + mddev->safemode_delay);
}
}
static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
#define SYNC_MARKS 10
#define SYNC_MARK_STEP (3*HZ)
static void md_do_sync(mddev_t *mddev)
{
mddev_t *mddev2;
unsigned int currspeed = 0,
window;
sector_t max_sectors,j, io_sectors;
unsigned long mark[SYNC_MARKS];
sector_t mark_cnt[SYNC_MARKS];
int last_mark,m;
struct list_head *tmp;
sector_t last_check;
int skipped = 0;
/* just incase thread restarts... */
if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
return;
/* we overload curr_resync somewhat here.
* 0 == not engaged in resync at all
* 2 == checking that there is no conflict with another sync
* 1 == like 2, but have yielded to allow conflicting resync to
* commense
* other == active in resync - this many blocks
*
* Before starting a resync we must have set curr_resync to
* 2, and then checked that every "conflicting" array has curr_resync
* less than ours. When we find one that is the same or higher
* we wait on resync_wait. To avoid deadlock, we reduce curr_resync
* to 1 if we choose to yield (based arbitrarily on address of mddev structure).
* This will mean we have to start checking from the beginning again.
*
*/
do {
mddev->curr_resync = 2;
try_again:
if (signal_pending(current)) {
flush_signals(current);
goto skip;
}
ITERATE_MDDEV(mddev2,tmp) {
if (mddev2 == mddev)
continue;
if (mddev2->curr_resync &&
match_mddev_units(mddev,mddev2)) {
DEFINE_WAIT(wq);
if (mddev < mddev2 && mddev->curr_resync == 2) {
/* arbitrarily yield */
mddev->curr_resync = 1;
wake_up(&resync_wait);
}
if (mddev > mddev2 && mddev->curr_resync == 1)
/* no need to wait here, we can wait the next
* time 'round when curr_resync == 2
*/
continue;
prepare_to_wait(&resync_wait, &wq, TASK_INTERRUPTIBLE);
if (!signal_pending(current)
&& mddev2->curr_resync >= mddev->curr_resync) {
printk(KERN_INFO "md: delaying resync of %s"
" until %s has finished resync (they"
" share one or more physical units)\n",
mdname(mddev), mdname(mddev2));
mddev_put(mddev2);
schedule();
finish_wait(&resync_wait, &wq);
goto try_again;
}
finish_wait(&resync_wait, &wq);
}
}
} while (mddev->curr_resync < 2);
if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
/* resync follows the size requested by the personality,
* which defaults to physical size, but can be virtual size
*/
max_sectors = mddev->resync_max_sectors;
else
/* recovery follows the physical size of devices */
max_sectors = mddev->size << 1;
printk(KERN_INFO "md: syncing RAID array %s\n", mdname(mddev));
printk(KERN_INFO "md: minimum _guaranteed_ reconstruction speed:"
" %d KB/sec/disc.\n", sysctl_speed_limit_min);
printk(KERN_INFO "md: using maximum available idle IO bandwith "
"(but not more than %d KB/sec) for reconstruction.\n",
sysctl_speed_limit_max);
is_mddev_idle(mddev); /* this also initializes IO event counters */
/* we don't use the checkpoint if there's a bitmap */
if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && !mddev->bitmap)
j = mddev->recovery_cp;
else
j = 0;
io_sectors = 0;
for (m = 0; m < SYNC_MARKS; m++) {
mark[m] = jiffies;
mark_cnt[m] = io_sectors;
}
last_mark = 0;
mddev->resync_mark = mark[last_mark];
mddev->resync_mark_cnt = mark_cnt[last_mark];
/*
* Tune reconstruction:
*/
window = 32*(PAGE_SIZE/512);
printk(KERN_INFO "md: using %dk window, over a total of %llu blocks.\n",
window/2,(unsigned long long) max_sectors/2);
atomic_set(&mddev->recovery_active, 0);
init_waitqueue_head(&mddev->recovery_wait);
last_check = 0;
if (j>2) {
printk(KERN_INFO
"md: resuming recovery of %s from checkpoint.\n",
mdname(mddev));
mddev->curr_resync = j;
}
while (j < max_sectors) {
sector_t sectors;
skipped = 0;
sectors = mddev->pers->sync_request(mddev, j, &skipped,
currspeed < sysctl_speed_limit_min);
if (sectors == 0) {
set_bit(MD_RECOVERY_ERR, &mddev->recovery);
goto out;
}
if (!skipped) { /* actual IO requested */
io_sectors += sectors;
atomic_add(sectors, &mddev->recovery_active);
}
j += sectors;
if (j>1) mddev->curr_resync = j;
if (last_check + window > io_sectors || j == max_sectors)
continue;
last_check = io_sectors;
if (test_bit(MD_RECOVERY_INTR, &mddev->recovery) ||
test_bit(MD_RECOVERY_ERR, &mddev->recovery))
break;
repeat:
if (time_after_eq(jiffies, mark[last_mark] + SYNC_MARK_STEP )) {
/* step marks */
int next = (last_mark+1) % SYNC_MARKS;
mddev->resync_mark = mark[next];
mddev->resync_mark_cnt = mark_cnt[next];
mark[next] = jiffies;
mark_cnt[next] = io_sectors - atomic_read(&mddev->recovery_active);
last_mark = next;
}
if (signal_pending(current)) {
/*
* got a signal, exit.
*/
printk(KERN_INFO
"md: md_do_sync() got signal ... exiting\n");
flush_signals(current);
set_bit(MD_RECOVERY_INTR, &mddev->recovery);
goto out;
}
/*
* this loop exits only if either when we are slower than
* the 'hard' speed limit, or the system was IO-idle for
* a jiffy.
* the system might be non-idle CPU-wise, but we only care
* about not overloading the IO subsystem. (things like an
* e2fsck being done on the RAID array should execute fast)
*/
mddev->queue->unplug_fn(mddev->queue);
cond_resched();
currspeed = ((unsigned long)(io_sectors-mddev->resync_mark_cnt))/2
/((jiffies-mddev->resync_mark)/HZ +1) +1;
if (currspeed > sysctl_speed_limit_min) {
if ((currspeed > sysctl_speed_limit_max) ||
!is_mddev_idle(mddev)) {
msleep_interruptible(250);
goto repeat;
}
}
}
printk(KERN_INFO "md: %s: sync done.\n",mdname(mddev));
/*
* this also signals 'finished resyncing' to md_stop
*/
out:
mddev->queue->unplug_fn(mddev->queue);
wait_event(mddev->recovery_wait, !atomic_read(&mddev->recovery_active));
/* tell personality that we are finished */
mddev->pers->sync_request(mddev, max_sectors, &skipped, 1);
if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
mddev->curr_resync > 2 &&
mddev->curr_resync >= mddev->recovery_cp) {
if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
printk(KERN_INFO
"md: checkpointing recovery of %s.\n",
mdname(mddev));
mddev->recovery_cp = mddev->curr_resync;
} else
mddev->recovery_cp = MaxSector;
}
skip:
mddev->curr_resync = 0;
wake_up(&resync_wait);
set_bit(MD_RECOVERY_DONE, &mddev->recovery);
md_wakeup_thread(mddev->thread);
}
/*
* This routine is regularly called by all per-raid-array threads to
* deal with generic issues like resync and super-block update.
* Raid personalities that don't have a thread (linear/raid0) do not
* need this as they never do any recovery or update the superblock.
*
* It does not do any resync itself, but rather "forks" off other threads
* to do that as needed.
* When it is determined that resync is needed, we set MD_RECOVERY_RUNNING in
* "->recovery" and create a thread at ->sync_thread.
* When the thread finishes it sets MD_RECOVERY_DONE (and might set MD_RECOVERY_ERR)
* and wakeups up this thread which will reap the thread and finish up.
* This thread also removes any faulty devices (with nr_pending == 0).
*
* The overall approach is:
* 1/ if the superblock needs updating, update it.
* 2/ If a recovery thread is running, don't do anything else.
* 3/ If recovery has finished, clean up, possibly marking spares active.
* 4/ If there are any faulty devices, remove them.
* 5/ If array is degraded, try to add spares devices
* 6/ If array has spares or is not in-sync, start a resync thread.
*/
void md_check_recovery(mddev_t *mddev)
{
mdk_rdev_t *rdev;
struct list_head *rtmp;
if (mddev->bitmap)
bitmap_daemon_work(mddev->bitmap);
if (mddev->ro)
return;
if (signal_pending(current)) {
if (mddev->pers->sync_request) {
printk(KERN_INFO "md: %s in immediate safe mode\n",
mdname(mddev));
mddev->safemode = 2;
}
flush_signals(current);
}
if ( ! (
mddev->sb_dirty ||
test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
test_bit(MD_RECOVERY_DONE, &mddev->recovery) ||
(mddev->safemode == 1) ||
(mddev->safemode == 2 && ! atomic_read(&mddev->writes_pending)
&& !mddev->in_sync && mddev->recovery_cp == MaxSector)
))
return;
if (mddev_trylock(mddev)==0) {
int spares =0;
spin_lock(&mddev->write_lock);
if (mddev->safemode && !atomic_read(&mddev->writes_pending) &&
!mddev->in_sync && mddev->recovery_cp == MaxSector) {
mddev->in_sync = 1;
mddev->sb_dirty = 1;
}
if (mddev->safemode == 1)
mddev->safemode = 0;
spin_unlock(&mddev->write_lock);
if (mddev->sb_dirty)
md_update_sb(mddev);
if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
!test_bit(MD_RECOVERY_DONE, &mddev->recovery)) {
/* resync/recovery still happening */
clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
goto unlock;
}
if (mddev->sync_thread) {
/* resync has finished, collect result */
md_unregister_thread(mddev->sync_thread);
mddev->sync_thread = NULL;
if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
/* success...*/
/* activate any spares */
mddev->pers->spare_active(mddev);
}
md_update_sb(mddev);
/* if array is no-longer degraded, then any saved_raid_disk
* information must be scrapped
*/
if (!mddev->degraded)
ITERATE_RDEV(mddev,rdev,rtmp)
rdev->saved_raid_disk = -1;
mddev->recovery = 0;
/* flag recovery needed just to double check */
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
goto unlock;
}
if (mddev->recovery)
/* probably just the RECOVERY_NEEDED flag */
mddev->recovery = 0;
/* no recovery is running.
* remove any failed drives, then
* add spares if possible.
* Spare are also removed and re-added, to allow
* the personality to fail the re-add.
*/
ITERATE_RDEV(mddev,rdev,rtmp)
if (rdev->raid_disk >= 0 &&
(rdev->faulty || ! rdev->in_sync) &&
atomic_read(&rdev->nr_pending)==0) {
if (mddev->pers->hot_remove_disk(mddev, rdev->raid_disk)==0)
rdev->raid_disk = -1;
}
if (mddev->degraded) {
ITERATE_RDEV(mddev,rdev,rtmp)
if (rdev->raid_disk < 0
&& !rdev->faulty) {
if (mddev->pers->hot_add_disk(mddev,rdev))
spares++;
else
break;
}
}
if (!spares && (mddev->recovery_cp == MaxSector )) {
/* nothing we can do ... */
goto unlock;
}
if (mddev->pers->sync_request) {
set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
if (!spares)
set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
if (spares && mddev->bitmap && ! mddev->bitmap->file) {
/* We are adding a device or devices to an array
* which has the bitmap stored on all devices.
* So make sure all bitmap pages get written
*/
bitmap_write_all(mddev->bitmap);
}
mddev->sync_thread = md_register_thread(md_do_sync,
mddev,
"%s_resync");
if (!mddev->sync_thread) {
printk(KERN_ERR "%s: could not start resync"
" thread...\n",
mdname(mddev));
/* leave the spares where they are, it shouldn't hurt */
mddev->recovery = 0;
} else {
md_wakeup_thread(mddev->sync_thread);
}
}
unlock:
mddev_unlock(mddev);
}
}
static int md_notify_reboot(struct notifier_block *this,
unsigned long code, void *x)
{
struct list_head *tmp;
mddev_t *mddev;
if ((code == SYS_DOWN) || (code == SYS_HALT) || (code == SYS_POWER_OFF)) {
printk(KERN_INFO "md: stopping all md devices.\n");
ITERATE_MDDEV(mddev,tmp)
if (mddev_trylock(mddev)==0)
do_md_stop (mddev, 1);
/*
* certain more exotic SCSI devices are known to be
* volatile wrt too early system reboots. While the
* right place to handle this issue is the given
* driver, we do want to have a safe RAID driver ...
*/
mdelay(1000*1);
}
return NOTIFY_DONE;
}
static struct notifier_block md_notifier = {
.notifier_call = md_notify_reboot,
.next = NULL,
.priority = INT_MAX, /* before any real devices */
};
static void md_geninit(void)
{
struct proc_dir_entry *p;
dprintk("md: sizeof(mdp_super_t) = %d\n", (int)sizeof(mdp_super_t));
p = create_proc_entry("mdstat", S_IRUGO, NULL);
if (p)
p->proc_fops = &md_seq_fops;
}
static int __init md_init(void)
{
int minor;
printk(KERN_INFO "md: md driver %d.%d.%d MAX_MD_DEVS=%d,"
" MD_SB_DISKS=%d\n",
MD_MAJOR_VERSION, MD_MINOR_VERSION,
MD_PATCHLEVEL_VERSION, MAX_MD_DEVS, MD_SB_DISKS);
printk(KERN_INFO "md: bitmap version %d.%d\n", BITMAP_MAJOR,
BITMAP_MINOR);
if (register_blkdev(MAJOR_NR, "md"))
return -1;
if ((mdp_major=register_blkdev(0, "mdp"))<=0) {
unregister_blkdev(MAJOR_NR, "md");
return -1;
}
devfs_mk_dir("md");
blk_register_region(MKDEV(MAJOR_NR, 0), MAX_MD_DEVS, THIS_MODULE,
md_probe, NULL, NULL);
blk_register_region(MKDEV(mdp_major, 0), MAX_MD_DEVS<<MdpMinorShift, THIS_MODULE,
md_probe, NULL, NULL);
for (minor=0; minor < MAX_MD_DEVS; ++minor)
devfs_mk_bdev(MKDEV(MAJOR_NR, minor),
S_IFBLK|S_IRUSR|S_IWUSR,
"md/%d", minor);
for (minor=0; minor < MAX_MD_DEVS; ++minor)
devfs_mk_bdev(MKDEV(mdp_major, minor<<MdpMinorShift),
S_IFBLK|S_IRUSR|S_IWUSR,
"md/mdp%d", minor);
register_reboot_notifier(&md_notifier);
raid_table_header = register_sysctl_table(raid_root_table, 1);
md_geninit();
return (0);
}
#ifndef MODULE
/*
* Searches all registered partitions for autorun RAID arrays
* at boot time.
*/
static dev_t detected_devices[128];
static int dev_cnt;
void md_autodetect_dev(dev_t dev)
{
if (dev_cnt >= 0 && dev_cnt < 127)
detected_devices[dev_cnt++] = dev;
}
static void autostart_arrays(int part)
{
mdk_rdev_t *rdev;
int i;
printk(KERN_INFO "md: Autodetecting RAID arrays.\n");
for (i = 0; i < dev_cnt; i++) {
dev_t dev = detected_devices[i];
rdev = md_import_device(dev,0, 0);
if (IS_ERR(rdev))
continue;
if (rdev->faulty) {
MD_BUG();
continue;
}
list_add(&rdev->same_set, &pending_raid_disks);
}
dev_cnt = 0;
autorun_devices(part);
}
#endif
static __exit void md_exit(void)
{
mddev_t *mddev;
struct list_head *tmp;
int i;
blk_unregister_region(MKDEV(MAJOR_NR,0), MAX_MD_DEVS);
blk_unregister_region(MKDEV(mdp_major,0), MAX_MD_DEVS << MdpMinorShift);
for (i=0; i < MAX_MD_DEVS; i++)
devfs_remove("md/%d", i);
for (i=0; i < MAX_MD_DEVS; i++)
devfs_remove("md/d%d", i);
devfs_remove("md");
unregister_blkdev(MAJOR_NR,"md");
unregister_blkdev(mdp_major, "mdp");
unregister_reboot_notifier(&md_notifier);
unregister_sysctl_table(raid_table_header);
remove_proc_entry("mdstat", NULL);
ITERATE_MDDEV(mddev,tmp) {
struct gendisk *disk = mddev->gendisk;
if (!disk)
continue;
export_array(mddev);
del_gendisk(disk);
put_disk(disk);
mddev->gendisk = NULL;
mddev_put(mddev);
}
}
module_init(md_init)
module_exit(md_exit)
EXPORT_SYMBOL(register_md_personality);
EXPORT_SYMBOL(unregister_md_personality);
EXPORT_SYMBOL(md_error);
EXPORT_SYMBOL(md_done_sync);
EXPORT_SYMBOL(md_write_start);
EXPORT_SYMBOL(md_write_end);
EXPORT_SYMBOL(md_register_thread);
EXPORT_SYMBOL(md_unregister_thread);
EXPORT_SYMBOL(md_wakeup_thread);
EXPORT_SYMBOL(md_print_devices);
EXPORT_SYMBOL(md_check_recovery);
MODULE_LICENSE("GPL");
MODULE_ALIAS("md");
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