Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-14 08:02:07 +00:00
Code Issues Packages Projects Releases Wiki Activity
314a8ad0f1
linux/fs/exofs/super.c
Eric W. Biederman 7f78e03513 fs: Limit sys_mount to only request filesystem modules. 
Modify the request_module to prefix the file system type with "fs-"
and add aliases to all of the filesystems that can be built as modules
to match.

A common practice is to build all of the kernel code and leave code
that is not commonly needed as modules, with the result that many
users are exposed to any bug anywhere in the kernel.

Looking for filesystems with a fs- prefix limits the pool of possible
modules that can be loaded by mount to just filesystems trivially
making things safer with no real cost.

Using aliases means user space can control the policy of which
filesystem modules are auto-loaded by editing /etc/modprobe.d/*.conf
with blacklist and alias directives.  Allowing simple, safe,
well understood work-arounds to known problematic software.

This also addresses a rare but unfortunate problem where the filesystem
name is not the same as it's module name and module auto-loading
would not work.  While writing this patch I saw a handful of such
cases.  The most significant being autofs that lives in the module
autofs4.

This is relevant to user namespaces because we can reach the request
module in get_fs_type() without having any special permissions, and
people get uncomfortable when a user specified string (in this case
the filesystem type) goes all of the way to request_module.

After having looked at this issue I don't think there is any
particular reason to perform any filtering or permission checks beyond
making it clear in the module request that we want a filesystem
module.  The common pattern in the kernel is to call request_module()
without regards to the users permissions.  In general all a filesystem
module does once loaded is call register_filesystem() and go to sleep.
Which means there is not much attack surface exposed by loading a
filesytem module unless the filesystem is mounted.  In a user
namespace filesystems are not mounted unless .fs_flags = FS_USERNS_MOUNT,
which most filesystems do not set today.

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Acked-by: Kees Cook <keescook@chromium.org>
Reported-by: Kees Cook <keescook@google.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-03-03 19:36:31 -08:00

1050 lines
26 KiB
C
Raw Blame History

/*
* Copyright (C) 2005, 2006
* Avishay Traeger (avishay@gmail.com)
* Copyright (C) 2008, 2009
* Boaz Harrosh <bharrosh@panasas.com>
*
* Copyrights for code taken from ext2:
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
* from
* linux/fs/minix/inode.c
* Copyright (C) 1991, 1992 Linus Torvalds
*
* This file is part of exofs.
*
* exofs 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. Since it is based on ext2, and the only
* valid version of GPL for the Linux kernel is version 2, the only valid
* version of GPL for exofs is version 2.
*
* exofs is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with exofs; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <linux/string.h>
#include <linux/parser.h>
#include <linux/vfs.h>
#include <linux/random.h>
#include <linux/module.h>
#include <linux/exportfs.h>
#include <linux/slab.h>
#include "exofs.h"
#define EXOFS_DBGMSG2(M...) do {} while (0)
/******************************************************************************
* MOUNT OPTIONS
*****************************************************************************/
/*
* struct to hold what we get from mount options
*/
struct exofs_mountopt {
bool is_osdname;
const char *dev_name;
uint64_t pid;
int timeout;
};
/*
* exofs-specific mount-time options.
*/
enum { Opt_name, Opt_pid, Opt_to, Opt_err };
/*
* Our mount-time options. These should ideally be 64-bit unsigned, but the
* kernel's parsing functions do not currently support that. 32-bit should be
* sufficient for most applications now.
*/
static match_table_t tokens = {
{Opt_name, "osdname=%s"},
{Opt_pid, "pid=%u"},
{Opt_to, "to=%u"},
{Opt_err, NULL}
};
/*
* The main option parsing method. Also makes sure that all of the mandatory
* mount options were set.
*/
static int parse_options(char *options, struct exofs_mountopt *opts)
{
char *p;
substring_t args[MAX_OPT_ARGS];
int option;
bool s_pid = false;
EXOFS_DBGMSG("parse_options %s\n", options);
/* defaults */
memset(opts, 0, sizeof(*opts));
opts->timeout = BLK_DEFAULT_SG_TIMEOUT;
while ((p = strsep(&options, ",")) != NULL) {
int token;
char str[32];
if (!*p)
continue;
token = match_token(p, tokens, args);
switch (token) {
case Opt_name:
opts->dev_name = match_strdup(&args[0]);
if (unlikely(!opts->dev_name)) {
EXOFS_ERR("Error allocating dev_name");
return -ENOMEM;
}
opts->is_osdname = true;
break;
case Opt_pid:
if (0 == match_strlcpy(str, &args[0], sizeof(str)))
return -EINVAL;
opts->pid = simple_strtoull(str, NULL, 0);
if (opts->pid < EXOFS_MIN_PID) {
EXOFS_ERR("Partition ID must be >= %u",
EXOFS_MIN_PID);
return -EINVAL;
}
s_pid = 1;
break;
case Opt_to:
if (match_int(&args[0], &option))
return -EINVAL;
if (option <= 0) {
EXOFS_ERR("Timout must be > 0");
return -EINVAL;
}
opts->timeout = option * HZ;
break;
}
}
if (!s_pid) {
EXOFS_ERR("Need to specify the following options:\n");
EXOFS_ERR(" -o pid=pid_no_to_use\n");
return -EINVAL;
}
return 0;
}
/******************************************************************************
* INODE CACHE
*****************************************************************************/
/*
* Our inode cache. Isn't it pretty?
*/
static struct kmem_cache *exofs_inode_cachep;
/*
* Allocate an inode in the cache
*/
static struct inode *exofs_alloc_inode(struct super_block *sb)
{
struct exofs_i_info *oi;
oi = kmem_cache_alloc(exofs_inode_cachep, GFP_KERNEL);
if (!oi)
return NULL;
oi->vfs_inode.i_version = 1;
return &oi->vfs_inode;
}
static void exofs_i_callback(struct rcu_head *head)
{
struct inode *inode = container_of(head, struct inode, i_rcu);
kmem_cache_free(exofs_inode_cachep, exofs_i(inode));
}
/*
* Remove an inode from the cache
*/
static void exofs_destroy_inode(struct inode *inode)
{
call_rcu(&inode->i_rcu, exofs_i_callback);
}
/*
* Initialize the inode
*/
static void exofs_init_once(void *foo)
{
struct exofs_i_info *oi = foo;
inode_init_once(&oi->vfs_inode);
}
/*
* Create and initialize the inode cache
*/
static int init_inodecache(void)
{
exofs_inode_cachep = kmem_cache_create("exofs_inode_cache",
sizeof(struct exofs_i_info), 0,
SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
exofs_init_once);
if (exofs_inode_cachep == NULL)
return -ENOMEM;
return 0;
}
/*
* Destroy the inode cache
*/
static void destroy_inodecache(void)
{
/*
* Make sure all delayed rcu free inodes are flushed before we
* destroy cache.
*/
rcu_barrier();
kmem_cache_destroy(exofs_inode_cachep);
}
/******************************************************************************
* Some osd helpers
*****************************************************************************/
void exofs_make_credential(u8 cred_a[OSD_CAP_LEN], const struct osd_obj_id *obj)
{
osd_sec_init_nosec_doall_caps(cred_a, obj, false, true);
}
static int exofs_read_kern(struct osd_dev *od, u8 *cred, struct osd_obj_id *obj,
u64 offset, void *p, unsigned length)
{
struct osd_request *or = osd_start_request(od, GFP_KERNEL);
/* struct osd_sense_info osi = {.key = 0};*/
int ret;
if (unlikely(!or)) {
EXOFS_DBGMSG("%s: osd_start_request failed.\n", __func__);
return -ENOMEM;
}
ret = osd_req_read_kern(or, obj, offset, p, length);
if (unlikely(ret)) {
EXOFS_DBGMSG("%s: osd_req_read_kern failed.\n", __func__);
goto out;
}
ret = osd_finalize_request(or, 0, cred, NULL);
if (unlikely(ret)) {
EXOFS_DBGMSG("Failed to osd_finalize_request() => %d\n", ret);
goto out;
}
ret = osd_execute_request(or);
if (unlikely(ret))
EXOFS_DBGMSG("osd_execute_request() => %d\n", ret);
/* osd_req_decode_sense(or, ret); */
out:
osd_end_request(or);
EXOFS_DBGMSG2("read_kern(0x%llx) offset=0x%llx "
"length=0x%llx dev=%p ret=>%d\n",
_LLU(obj->id), _LLU(offset), _LLU(length), od, ret);
return ret;
}
static const struct osd_attr g_attr_sb_stats = ATTR_DEF(
EXOFS_APAGE_SB_DATA,
EXOFS_ATTR_SB_STATS,
sizeof(struct exofs_sb_stats));
static int __sbi_read_stats(struct exofs_sb_info *sbi)
{
struct osd_attr attrs[] = {
[0] = g_attr_sb_stats,
};
struct ore_io_state *ios;
int ret;
ret = ore_get_io_state(&sbi->layout, &sbi->oc, &ios);
if (unlikely(ret)) {
EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
return ret;
}
ios->in_attr = attrs;
ios->in_attr_len = ARRAY_SIZE(attrs);
ret = ore_read(ios);
if (unlikely(ret)) {
EXOFS_ERR("Error reading super_block stats => %d\n", ret);
goto out;
}
ret = extract_attr_from_ios(ios, &attrs[0]);
if (ret) {
EXOFS_ERR("%s: extract_attr of sb_stats failed\n", __func__);
goto out;
}
if (attrs[0].len) {
struct exofs_sb_stats *ess;
if (unlikely(attrs[0].len != sizeof(*ess))) {
EXOFS_ERR("%s: Wrong version of exofs_sb_stats "
"size(%d) != expected(%zd)\n",
__func__, attrs[0].len, sizeof(*ess));
goto out;
}
ess = attrs[0].val_ptr;
sbi->s_nextid = le64_to_cpu(ess->s_nextid);
sbi->s_numfiles = le32_to_cpu(ess->s_numfiles);
}
out:
ore_put_io_state(ios);
return ret;
}
static void stats_done(struct ore_io_state *ios, void *p)
{
ore_put_io_state(ios);
/* Good thanks nothing to do anymore */
}
/* Asynchronously write the stats attribute */
int exofs_sbi_write_stats(struct exofs_sb_info *sbi)
{
struct osd_attr attrs[] = {
[0] = g_attr_sb_stats,
};
struct ore_io_state *ios;
int ret;
ret = ore_get_io_state(&sbi->layout, &sbi->oc, &ios);
if (unlikely(ret)) {
EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
return ret;
}
sbi->s_ess.s_nextid = cpu_to_le64(sbi->s_nextid);
sbi->s_ess.s_numfiles = cpu_to_le64(sbi->s_numfiles);
attrs[0].val_ptr = &sbi->s_ess;
ios->done = stats_done;
ios->private = sbi;
ios->out_attr = attrs;
ios->out_attr_len = ARRAY_SIZE(attrs);
ret = ore_write(ios);
if (unlikely(ret)) {
EXOFS_ERR("%s: ore_write failed.\n", __func__);
ore_put_io_state(ios);
}
return ret;
}
/******************************************************************************
* SUPERBLOCK FUNCTIONS
*****************************************************************************/
static const struct super_operations exofs_sops;
static const struct export_operations exofs_export_ops;
/*
* Write the superblock to the OSD
*/
static int exofs_sync_fs(struct super_block *sb, int wait)
{
struct exofs_sb_info *sbi;
struct exofs_fscb *fscb;
struct ore_comp one_comp;
struct ore_components oc;
struct ore_io_state *ios;
int ret = -ENOMEM;
fscb = kmalloc(sizeof(*fscb), GFP_KERNEL);
if (unlikely(!fscb))
return -ENOMEM;
sbi = sb->s_fs_info;
/* NOTE: We no longer dirty the super_block anywhere in exofs. The
* reason we write the fscb here on unmount is so we can stay backwards
* compatible with fscb->s_version == 1. (What we are not compatible
* with is if a new version FS crashed and then we try to mount an old
* version). Otherwise the exofs_fscb is read-only from mkfs time. All
* the writeable info is set in exofs_sbi_write_stats() above.
*/
exofs_init_comps(&oc, &one_comp, sbi, EXOFS_SUPER_ID);
ret = ore_get_io_state(&sbi->layout, &oc, &ios);
if (unlikely(ret))
goto out;
ios->length = offsetof(struct exofs_fscb, s_dev_table_oid);
memset(fscb, 0, ios->length);
fscb->s_nextid = cpu_to_le64(sbi->s_nextid);
fscb->s_numfiles = cpu_to_le64(sbi->s_numfiles);
fscb->s_magic = cpu_to_le16(sb->s_magic);
fscb->s_newfs = 0;
fscb->s_version = EXOFS_FSCB_VER;
ios->offset = 0;
ios->kern_buff = fscb;
ret = ore_write(ios);
if (unlikely(ret))
EXOFS_ERR("%s: ore_write failed.\n", __func__);
out:
EXOFS_DBGMSG("s_nextid=0x%llx ret=%d\n", _LLU(sbi->s_nextid), ret);
ore_put_io_state(ios);
kfree(fscb);
return ret;
}
static void _exofs_print_device(const char *msg, const char *dev_path,
struct osd_dev *od, u64 pid)
{
const struct osd_dev_info *odi = osduld_device_info(od);
printk(KERN_NOTICE "exofs: %s %s osd_name-%s pid-0x%llx\n",
msg, dev_path ?: "", odi->osdname, _LLU(pid));
}
static void exofs_free_sbi(struct exofs_sb_info *sbi)
{
unsigned numdevs = sbi->oc.numdevs;
while (numdevs) {
unsigned i = --numdevs;
struct osd_dev *od = ore_comp_dev(&sbi->oc, i);
if (od) {
ore_comp_set_dev(&sbi->oc, i, NULL);
osduld_put_device(od);
}
}
kfree(sbi->oc.ods);
kfree(sbi);
}
/*
* This function is called when the vfs is freeing the superblock. We just
* need to free our own part.
*/
static void exofs_put_super(struct super_block *sb)
{
int num_pend;
struct exofs_sb_info *sbi = sb->s_fs_info;
/* make sure there are no pending commands */
for (num_pend = atomic_read(&sbi->s_curr_pending); num_pend > 0;
num_pend = atomic_read(&sbi->s_curr_pending)) {
wait_queue_head_t wq;
printk(KERN_NOTICE "%s: !!Pending operations in flight. "
"This is a BUG. please report to osd-dev@open-osd.org\n",
__func__);
init_waitqueue_head(&wq);
wait_event_timeout(wq,
(atomic_read(&sbi->s_curr_pending) == 0),
msecs_to_jiffies(100));
}
_exofs_print_device("Unmounting", NULL, ore_comp_dev(&sbi->oc, 0),
sbi->one_comp.obj.partition);
exofs_sysfs_sb_del(sbi);
bdi_destroy(&sbi->bdi);
exofs_free_sbi(sbi);
sb->s_fs_info = NULL;
}
static int _read_and_match_data_map(struct exofs_sb_info *sbi, unsigned numdevs,
struct exofs_device_table *dt)
{
int ret;
sbi->layout.stripe_unit =
le64_to_cpu(dt->dt_data_map.cb_stripe_unit);
sbi->layout.group_width =
le32_to_cpu(dt->dt_data_map.cb_group_width);
sbi->layout.group_depth =
le32_to_cpu(dt->dt_data_map.cb_group_depth);
sbi->layout.mirrors_p1 =
le32_to_cpu(dt->dt_data_map.cb_mirror_cnt) + 1;
sbi->layout.raid_algorithm =
le32_to_cpu(dt->dt_data_map.cb_raid_algorithm);
ret = ore_verify_layout(numdevs, &sbi->layout);
EXOFS_DBGMSG("exofs: layout: "
"num_comps=%u stripe_unit=0x%x group_width=%u "
"group_depth=0x%llx mirrors_p1=%u raid_algorithm=%u\n",
numdevs,
sbi->layout.stripe_unit,
sbi->layout.group_width,
_LLU(sbi->layout.group_depth),
sbi->layout.mirrors_p1,
sbi->layout.raid_algorithm);
return ret;
}
static unsigned __ra_pages(struct ore_layout *layout)
{
const unsigned _MIN_RA = 32; /* min 128K read-ahead */
unsigned ra_pages = layout->group_width * layout->stripe_unit /
PAGE_SIZE;
unsigned max_io_pages = exofs_max_io_pages(layout, ~0);
ra_pages *= 2; /* two stripes */
if (ra_pages < _MIN_RA)
ra_pages = roundup(_MIN_RA, ra_pages / 2);
if (ra_pages > max_io_pages)
ra_pages = max_io_pages;
return ra_pages;
}
/* @odi is valid only as long as @fscb_dev is valid */
static int exofs_devs_2_odi(struct exofs_dt_device_info *dt_dev,
struct osd_dev_info *odi)
{
odi->systemid_len = le32_to_cpu(dt_dev->systemid_len);
if (likely(odi->systemid_len))
memcpy(odi->systemid, dt_dev->systemid, OSD_SYSTEMID_LEN);
odi->osdname_len = le32_to_cpu(dt_dev->osdname_len);
odi->osdname = dt_dev->osdname;
/* FIXME support long names. Will need a _put function */
if (dt_dev->long_name_offset)
return -EINVAL;
/* Make sure osdname is printable!
* mkexofs should give us space for a null-terminator else the
* device-table is invalid.
*/
if (unlikely(odi->osdname_len >= sizeof(dt_dev->osdname)))
odi->osdname_len = sizeof(dt_dev->osdname) - 1;
dt_dev->osdname[odi->osdname_len] = 0;
/* If it's all zeros something is bad we read past end-of-obj */
return !(odi->systemid_len || odi->osdname_len);
}
int __alloc_dev_table(struct exofs_sb_info *sbi, unsigned numdevs,
struct exofs_dev **peds)
{
struct __alloc_ore_devs_and_exofs_devs {
/* Twice bigger table: See exofs_init_comps() and comment at
* exofs_read_lookup_dev_table()
*/
struct ore_dev *oreds[numdevs * 2 - 1];
struct exofs_dev eds[numdevs];
} *aoded;
struct exofs_dev *eds;
unsigned i;
aoded = kzalloc(sizeof(*aoded), GFP_KERNEL);
if (unlikely(!aoded)) {
EXOFS_ERR("ERROR: failed allocating Device array[%d]\n",
numdevs);
return -ENOMEM;
}
sbi->oc.ods = aoded->oreds;
*peds = eds = aoded->eds;
for (i = 0; i < numdevs; ++i)
aoded->oreds[i] = &eds[i].ored;
return 0;
}
static int exofs_read_lookup_dev_table(struct exofs_sb_info *sbi,
struct osd_dev *fscb_od,
unsigned table_count)
{
struct ore_comp comp;
struct exofs_device_table *dt;
struct exofs_dev *eds;
unsigned table_bytes = table_count * sizeof(dt->dt_dev_table[0]) +
sizeof(*dt);
unsigned numdevs, i;
int ret;
dt = kmalloc(table_bytes, GFP_KERNEL);
if (unlikely(!dt)) {
EXOFS_ERR("ERROR: allocating %x bytes for device table\n",
table_bytes);
return -ENOMEM;
}
sbi->oc.numdevs = 0;
comp.obj.partition = sbi->one_comp.obj.partition;
comp.obj.id = EXOFS_DEVTABLE_ID;
exofs_make_credential(comp.cred, &comp.obj);
ret = exofs_read_kern(fscb_od, comp.cred, &comp.obj, 0, dt,
table_bytes);
if (unlikely(ret)) {
EXOFS_ERR("ERROR: reading device table\n");
goto out;
}
numdevs = le64_to_cpu(dt->dt_num_devices);
if (unlikely(!numdevs)) {
ret = -EINVAL;
goto out;
}
WARN_ON(table_count != numdevs);
ret = _read_and_match_data_map(sbi, numdevs, dt);
if (unlikely(ret))
goto out;
ret = __alloc_dev_table(sbi, numdevs, &eds);
if (unlikely(ret))
goto out;
/* exofs round-robins the device table view according to inode
* number. We hold a: twice bigger table hence inodes can point
* to any device and have a sequential view of the table
* starting at this device. See exofs_init_comps()
*/
memcpy(&sbi->oc.ods[numdevs], &sbi->oc.ods[0],
(numdevs - 1) * sizeof(sbi->oc.ods[0]));
/* create sysfs subdir under which we put the device table
* And cluster layout. A Superblock is identified by the string:
* "dev[0].osdname"_"pid"
*/
exofs_sysfs_sb_add(sbi, &dt->dt_dev_table[0]);
for (i = 0; i < numdevs; i++) {
struct exofs_fscb fscb;
struct osd_dev_info odi;
struct osd_dev *od;
if (exofs_devs_2_odi(&dt->dt_dev_table[i], &odi)) {
EXOFS_ERR("ERROR: Read all-zeros device entry\n");
ret = -EINVAL;
goto out;
}
printk(KERN_NOTICE "Add device[%d]: osd_name-%s\n",
i, odi.osdname);
/* the exofs id is currently the table index */
eds[i].did = i;
/* On all devices the device table is identical. The user can
* specify any one of the participating devices on the command
* line. We always keep them in device-table order.
*/
if (fscb_od && osduld_device_same(fscb_od, &odi)) {
eds[i].ored.od = fscb_od;
++sbi->oc.numdevs;
fscb_od = NULL;
exofs_sysfs_odev_add(&eds[i], sbi);
continue;
}
od = osduld_info_lookup(&odi);
if (IS_ERR(od)) {
ret = PTR_ERR(od);
EXOFS_ERR("ERROR: device requested is not found "
"osd_name-%s =>%d\n", odi.osdname, ret);
goto out;
}
eds[i].ored.od = od;
++sbi->oc.numdevs;
/* Read the fscb of the other devices to make sure the FS
* partition is there.
*/
ret = exofs_read_kern(od, comp.cred, &comp.obj, 0, &fscb,
sizeof(fscb));
if (unlikely(ret)) {
EXOFS_ERR("ERROR: Malformed participating device "
"error reading fscb osd_name-%s\n",
odi.osdname);
goto out;
}
exofs_sysfs_odev_add(&eds[i], sbi);
/* TODO: verify other information is correct and FS-uuid
* matches. Benny what did you say about device table
* generation and old devices?
*/
}
out:
kfree(dt);
if (unlikely(fscb_od && !ret)) {
EXOFS_ERR("ERROR: Bad device-table container device not present\n");
osduld_put_device(fscb_od);
return -EINVAL;
}
return ret;
}
/*
* Read the superblock from the OSD and fill in the fields
*/
static int exofs_fill_super(struct super_block *sb, void *data, int silent)
{
struct inode *root;
struct exofs_mountopt *opts = data;
struct exofs_sb_info *sbi; /*extended info */
struct osd_dev *od; /* Master device */
struct exofs_fscb fscb; /*on-disk superblock info */
struct ore_comp comp;
unsigned table_count;
int ret;
sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
if (!sbi)
return -ENOMEM;
/* use mount options to fill superblock */
if (opts->is_osdname) {
struct osd_dev_info odi = {.systemid_len = 0};
odi.osdname_len = strlen(opts->dev_name);
odi.osdname = (u8 *)opts->dev_name;
od = osduld_info_lookup(&odi);
kfree(opts->dev_name);
opts->dev_name = NULL;
} else {
od = osduld_path_lookup(opts->dev_name);
}
if (IS_ERR(od)) {
ret = -EINVAL;
goto free_sbi;
}
/* Default layout in case we do not have a device-table */
sbi->layout.stripe_unit = PAGE_SIZE;
sbi->layout.mirrors_p1 = 1;
sbi->layout.group_width = 1;
sbi->layout.group_depth = -1;
sbi->layout.group_count = 1;
sbi->s_timeout = opts->timeout;
sbi->one_comp.obj.partition = opts->pid;
sbi->one_comp.obj.id = 0;
exofs_make_credential(sbi->one_comp.cred, &sbi->one_comp.obj);
sbi->oc.single_comp = EC_SINGLE_COMP;
sbi->oc.comps = &sbi->one_comp;
/* fill in some other data by hand */
memset(sb->s_id, 0, sizeof(sb->s_id));
strcpy(sb->s_id, "exofs");
sb->s_blocksize = EXOFS_BLKSIZE;
sb->s_blocksize_bits = EXOFS_BLKSHIFT;
sb->s_maxbytes = MAX_LFS_FILESIZE;
sb->s_max_links = EXOFS_LINK_MAX;
atomic_set(&sbi->s_curr_pending, 0);
sb->s_bdev = NULL;
sb->s_dev = 0;
comp.obj.partition = sbi->one_comp.obj.partition;
comp.obj.id = EXOFS_SUPER_ID;
exofs_make_credential(comp.cred, &comp.obj);
ret = exofs_read_kern(od, comp.cred, &comp.obj, 0, &fscb, sizeof(fscb));
if (unlikely(ret))
goto free_sbi;
sb->s_magic = le16_to_cpu(fscb.s_magic);
/* NOTE: we read below to be backward compatible with old versions */
sbi->s_nextid = le64_to_cpu(fscb.s_nextid);
sbi->s_numfiles = le32_to_cpu(fscb.s_numfiles);
/* make sure what we read from the object store is correct */
if (sb->s_magic != EXOFS_SUPER_MAGIC) {
if (!silent)
EXOFS_ERR("ERROR: Bad magic value\n");
ret = -EINVAL;
goto free_sbi;
}
if (le32_to_cpu(fscb.s_version) > EXOFS_FSCB_VER) {
EXOFS_ERR("ERROR: Bad FSCB version expected-%d got-%d\n",
EXOFS_FSCB_VER, le32_to_cpu(fscb.s_version));
ret = -EINVAL;
goto free_sbi;
}
/* start generation numbers from a random point */
get_random_bytes(&sbi->s_next_generation, sizeof(u32));
spin_lock_init(&sbi->s_next_gen_lock);
table_count = le64_to_cpu(fscb.s_dev_table_count);
if (table_count) {
ret = exofs_read_lookup_dev_table(sbi, od, table_count);
if (unlikely(ret))
goto free_sbi;
} else {
struct exofs_dev *eds;
ret = __alloc_dev_table(sbi, 1, &eds);
if (unlikely(ret))
goto free_sbi;
ore_comp_set_dev(&sbi->oc, 0, od);
sbi->oc.numdevs = 1;
}
__sbi_read_stats(sbi);
/* set up operation vectors */
sbi->bdi.ra_pages = __ra_pages(&sbi->layout);
sb->s_bdi = &sbi->bdi;
sb->s_fs_info = sbi;
sb->s_op = &exofs_sops;
sb->s_export_op = &exofs_export_ops;
root = exofs_iget(sb, EXOFS_ROOT_ID - EXOFS_OBJ_OFF);
if (IS_ERR(root)) {
EXOFS_ERR("ERROR: exofs_iget failed\n");
ret = PTR_ERR(root);
goto free_sbi;
}
sb->s_root = d_make_root(root);
if (!sb->s_root) {
EXOFS_ERR("ERROR: get root inode failed\n");
ret = -ENOMEM;
goto free_sbi;
}
if (!S_ISDIR(root->i_mode)) {
dput(sb->s_root);
sb->s_root = NULL;
EXOFS_ERR("ERROR: corrupt root inode (mode = %hd)\n",
root->i_mode);
ret = -EINVAL;
goto free_sbi;
}
ret = bdi_setup_and_register(&sbi->bdi, "exofs", BDI_CAP_MAP_COPY);
if (ret) {
EXOFS_DBGMSG("Failed to bdi_setup_and_register\n");
dput(sb->s_root);
sb->s_root = NULL;
goto free_sbi;
}
exofs_sysfs_dbg_print();
_exofs_print_device("Mounting", opts->dev_name,
ore_comp_dev(&sbi->oc, 0),
sbi->one_comp.obj.partition);
return 0;
free_sbi:
EXOFS_ERR("Unable to mount exofs on %s pid=0x%llx err=%d\n",
opts->dev_name, sbi->one_comp.obj.partition, ret);
exofs_free_sbi(sbi);
return ret;
}
/*
* Set up the superblock (calls exofs_fill_super eventually)
*/
static struct dentry *exofs_mount(struct file_system_type *type,
int flags, const char *dev_name,
void *data)
{
struct exofs_mountopt opts;
int ret;
ret = parse_options(data, &opts);
if (ret)
return ERR_PTR(ret);
if (!opts.dev_name)
opts.dev_name = dev_name;
return mount_nodev(type, flags, &opts, exofs_fill_super);
}
/*
* Return information about the file system state in the buffer. This is used
* by the 'df' command, for example.
*/
static int exofs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
struct super_block *sb = dentry->d_sb;
struct exofs_sb_info *sbi = sb->s_fs_info;
struct ore_io_state *ios;
struct osd_attr attrs[] = {
ATTR_DEF(OSD_APAGE_PARTITION_QUOTAS,
OSD_ATTR_PQ_CAPACITY_QUOTA, sizeof(__be64)),
ATTR_DEF(OSD_APAGE_PARTITION_INFORMATION,
OSD_ATTR_PI_USED_CAPACITY, sizeof(__be64)),
};
uint64_t capacity = ULLONG_MAX;
uint64_t used = ULLONG_MAX;
int ret;
ret = ore_get_io_state(&sbi->layout, &sbi->oc, &ios);
if (ret) {
EXOFS_DBGMSG("ore_get_io_state failed.\n");
return ret;
}
ios->in_attr = attrs;
ios->in_attr_len = ARRAY_SIZE(attrs);
ret = ore_read(ios);
if (unlikely(ret))
goto out;
ret = extract_attr_from_ios(ios, &attrs[0]);
if (likely(!ret)) {
capacity = get_unaligned_be64(attrs[0].val_ptr);
if (unlikely(!capacity))
capacity = ULLONG_MAX;
} else
EXOFS_DBGMSG("exofs_statfs: get capacity failed.\n");
ret = extract_attr_from_ios(ios, &attrs[1]);
if (likely(!ret))
used = get_unaligned_be64(attrs[1].val_ptr);
else
EXOFS_DBGMSG("exofs_statfs: get used-space failed.\n");
/* fill in the stats buffer */
buf->f_type = EXOFS_SUPER_MAGIC;
buf->f_bsize = EXOFS_BLKSIZE;
buf->f_blocks = capacity >> 9;
buf->f_bfree = (capacity - used) >> 9;
buf->f_bavail = buf->f_bfree;
buf->f_files = sbi->s_numfiles;
buf->f_ffree = EXOFS_MAX_ID - sbi->s_numfiles;
buf->f_namelen = EXOFS_NAME_LEN;
out:
ore_put_io_state(ios);
return ret;
}
static const struct super_operations exofs_sops = {
.alloc_inode = exofs_alloc_inode,
.destroy_inode = exofs_destroy_inode,
.write_inode = exofs_write_inode,
.evict_inode = exofs_evict_inode,
.put_super = exofs_put_super,
.sync_fs = exofs_sync_fs,
.statfs = exofs_statfs,
};
/******************************************************************************
* EXPORT OPERATIONS
*****************************************************************************/
static struct dentry *exofs_get_parent(struct dentry *child)
{
unsigned long ino = exofs_parent_ino(child);
if (!ino)
return ERR_PTR(-ESTALE);
return d_obtain_alias(exofs_iget(child->d_inode->i_sb, ino));
}
static struct inode *exofs_nfs_get_inode(struct super_block *sb,
u64 ino, u32 generation)
{
struct inode *inode;
inode = exofs_iget(sb, ino);
if (IS_ERR(inode))
return ERR_CAST(inode);
if (generation && inode->i_generation != generation) {
/* we didn't find the right inode.. */
iput(inode);
return ERR_PTR(-ESTALE);
}
return inode;
}
static struct dentry *exofs_fh_to_dentry(struct super_block *sb,
struct fid *fid, int fh_len, int fh_type)
{
return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
exofs_nfs_get_inode);
}
static struct dentry *exofs_fh_to_parent(struct super_block *sb,
struct fid *fid, int fh_len, int fh_type)
{
return generic_fh_to_parent(sb, fid, fh_len, fh_type,
exofs_nfs_get_inode);
}
static const struct export_operations exofs_export_ops = {
.fh_to_dentry = exofs_fh_to_dentry,
.fh_to_parent = exofs_fh_to_parent,
.get_parent = exofs_get_parent,
};
/******************************************************************************
* INSMOD/RMMOD
*****************************************************************************/
/*
* struct that describes this file system
*/
static struct file_system_type exofs_type = {
.owner = THIS_MODULE,
.name = "exofs",
.mount = exofs_mount,
.kill_sb = generic_shutdown_super,
};
MODULE_ALIAS_FS("exofs");
static int __init init_exofs(void)
{
int err;
err = init_inodecache();
if (err)
goto out;
err = register_filesystem(&exofs_type);
if (err)
goto out_d;
/* We don't fail if sysfs creation failed */
exofs_sysfs_init();
return 0;
out_d:
destroy_inodecache();
out:
return err;
}
static void __exit exit_exofs(void)
{
exofs_sysfs_uninit();
unregister_filesystem(&exofs_type);
destroy_inodecache();
}
MODULE_AUTHOR("Avishay Traeger <avishay@gmail.com>");
MODULE_DESCRIPTION("exofs");
MODULE_LICENSE("GPL");
module_init(init_exofs)
module_exit(exit_exofs)
Reference in New Issue View Git Blame Copy Permalink