linux/fs/btrfs/volumes.h
Miao Xie c55f139640 Btrfs: fix deadlock when mounting a degraded fs
The deadlock happened when we mount degraded filesystem, the reproduced
steps are following:
 # mkfs.btrfs -f -m raid1 -d raid1 <dev0> <dev1>
 # echo 1 > /sys/block/`basename <dev0>`/device/delete
 # mount -o degraded <dev1> <mnt>

The reason was that the counter -- bi_remaining was wrong. If the missing
or unwriteable device was the last device in the mapping array, we would
not submit the original bio, so we shouldn't increase bi_remaining of it
in btrfs_end_bio(), or we would skip the final endio handle.

Fix this problem by adding a flag into btrfs bio structure. If we submit
the original bio, we will set the flag, and we increase bi_remaining counter,
or we don't.

Though there is another way to fix it -- decrease bi_remaining counter of the
original bio when we make sure the original bio is not submitted, this method
need add more check and is easy to make mistake.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-19 14:20:56 -07:00

399 lines
12 KiB
C

/*
* Copyright (C) 2007 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program 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 this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#ifndef __BTRFS_VOLUMES_
#define __BTRFS_VOLUMES_
#include <linux/bio.h>
#include <linux/sort.h>
#include <linux/btrfs.h>
#include "async-thread.h"
#define BTRFS_STRIPE_LEN (64 * 1024)
struct buffer_head;
struct btrfs_pending_bios {
struct bio *head;
struct bio *tail;
};
struct btrfs_device {
struct list_head dev_list;
struct list_head dev_alloc_list;
struct btrfs_fs_devices *fs_devices;
struct btrfs_root *dev_root;
/* regular prio bios */
struct btrfs_pending_bios pending_bios;
/* WRITE_SYNC bios */
struct btrfs_pending_bios pending_sync_bios;
u64 generation;
int running_pending;
int writeable;
int in_fs_metadata;
int missing;
int can_discard;
int is_tgtdev_for_dev_replace;
spinlock_t io_lock;
/* the mode sent to blkdev_get */
fmode_t mode;
struct block_device *bdev;
struct rcu_string *name;
/* the internal btrfs device id */
u64 devid;
/* size of the device */
u64 total_bytes;
/* size of the disk */
u64 disk_total_bytes;
/* bytes used */
u64 bytes_used;
/* optimal io alignment for this device */
u32 io_align;
/* optimal io width for this device */
u32 io_width;
/* type and info about this device */
u64 type;
/* minimal io size for this device */
u32 sector_size;
/* physical drive uuid (or lvm uuid) */
u8 uuid[BTRFS_UUID_SIZE];
/* for sending down flush barriers */
int nobarriers;
struct bio *flush_bio;
struct completion flush_wait;
/* per-device scrub information */
struct scrub_ctx *scrub_device;
struct btrfs_work work;
struct rcu_head rcu;
struct work_struct rcu_work;
/* readahead state */
spinlock_t reada_lock;
atomic_t reada_in_flight;
u64 reada_next;
struct reada_zone *reada_curr_zone;
struct radix_tree_root reada_zones;
struct radix_tree_root reada_extents;
/* disk I/O failure stats. For detailed description refer to
* enum btrfs_dev_stat_values in ioctl.h */
int dev_stats_valid;
int dev_stats_dirty; /* counters need to be written to disk */
atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
};
struct btrfs_fs_devices {
u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
/* the device with this id has the most recent copy of the super */
u64 latest_devid;
u64 latest_trans;
u64 num_devices;
u64 open_devices;
u64 rw_devices;
u64 missing_devices;
u64 total_rw_bytes;
u64 num_can_discard;
u64 total_devices;
struct block_device *latest_bdev;
/* all of the devices in the FS, protected by a mutex
* so we can safely walk it to write out the supers without
* worrying about add/remove by the multi-device code.
* Scrubbing super can kick off supers writing by holding
* this mutex lock.
*/
struct mutex device_list_mutex;
struct list_head devices;
/* devices not currently being allocated */
struct list_head alloc_list;
struct list_head list;
struct btrfs_fs_devices *seed;
int seeding;
int opened;
/* set when we find or add a device that doesn't have the
* nonrot flag set
*/
int rotating;
};
#define BTRFS_BIO_INLINE_CSUM_SIZE 64
/*
* we need the mirror number and stripe index to be passed around
* the call chain while we are processing end_io (especially errors).
* Really, what we need is a btrfs_bio structure that has this info
* and is properly sized with its stripe array, but we're not there
* quite yet. We have our own btrfs bioset, and all of the bios
* we allocate are actually btrfs_io_bios. We'll cram as much of
* struct btrfs_bio as we can into this over time.
*/
typedef void (btrfs_io_bio_end_io_t) (struct btrfs_io_bio *bio, int err);
struct btrfs_io_bio {
unsigned long mirror_num;
unsigned long stripe_index;
u8 *csum;
u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
u8 *csum_allocated;
btrfs_io_bio_end_io_t *end_io;
struct bio bio;
};
static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
{
return container_of(bio, struct btrfs_io_bio, bio);
}
struct btrfs_bio_stripe {
struct btrfs_device *dev;
u64 physical;
u64 length; /* only used for discard mappings */
};
struct btrfs_bio;
typedef void (btrfs_bio_end_io_t) (struct btrfs_bio *bio, int err);
#define BTRFS_BIO_ORIG_BIO_SUBMITTED 0x1
struct btrfs_bio {
atomic_t stripes_pending;
struct btrfs_fs_info *fs_info;
bio_end_io_t *end_io;
struct bio *orig_bio;
unsigned long flags;
void *private;
atomic_t error;
int max_errors;
int num_stripes;
int mirror_num;
struct btrfs_bio_stripe stripes[];
};
struct btrfs_device_info {
struct btrfs_device *dev;
u64 dev_offset;
u64 max_avail;
u64 total_avail;
};
struct btrfs_raid_attr {
int sub_stripes; /* sub_stripes info for map */
int dev_stripes; /* stripes per dev */
int devs_max; /* max devs to use */
int devs_min; /* min devs needed */
int devs_increment; /* ndevs has to be a multiple of this */
int ncopies; /* how many copies to data has */
};
struct map_lookup {
u64 type;
int io_align;
int io_width;
int stripe_len;
int sector_size;
int num_stripes;
int sub_stripes;
struct btrfs_bio_stripe stripes[];
};
#define map_lookup_size(n) (sizeof(struct map_lookup) + \
(sizeof(struct btrfs_bio_stripe) * (n)))
/*
* Restriper's general type filter
*/
#define BTRFS_BALANCE_DATA (1ULL << 0)
#define BTRFS_BALANCE_SYSTEM (1ULL << 1)
#define BTRFS_BALANCE_METADATA (1ULL << 2)
#define BTRFS_BALANCE_TYPE_MASK (BTRFS_BALANCE_DATA | \
BTRFS_BALANCE_SYSTEM | \
BTRFS_BALANCE_METADATA)
#define BTRFS_BALANCE_FORCE (1ULL << 3)
#define BTRFS_BALANCE_RESUME (1ULL << 4)
/*
* Balance filters
*/
#define BTRFS_BALANCE_ARGS_PROFILES (1ULL << 0)
#define BTRFS_BALANCE_ARGS_USAGE (1ULL << 1)
#define BTRFS_BALANCE_ARGS_DEVID (1ULL << 2)
#define BTRFS_BALANCE_ARGS_DRANGE (1ULL << 3)
#define BTRFS_BALANCE_ARGS_VRANGE (1ULL << 4)
#define BTRFS_BALANCE_ARGS_LIMIT (1ULL << 5)
/*
* Profile changing flags. When SOFT is set we won't relocate chunk if
* it already has the target profile (even though it may be
* half-filled).
*/
#define BTRFS_BALANCE_ARGS_CONVERT (1ULL << 8)
#define BTRFS_BALANCE_ARGS_SOFT (1ULL << 9)
struct btrfs_balance_args;
struct btrfs_balance_progress;
struct btrfs_balance_control {
struct btrfs_fs_info *fs_info;
struct btrfs_balance_args data;
struct btrfs_balance_args meta;
struct btrfs_balance_args sys;
u64 flags;
struct btrfs_balance_progress stat;
};
int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
u64 end, u64 *length);
#define btrfs_bio_size(n) (sizeof(struct btrfs_bio) + \
(sizeof(struct btrfs_bio_stripe) * (n)))
int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
u64 logical, u64 *length,
struct btrfs_bio **bbio_ret, int mirror_num);
int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
u64 chunk_start, u64 physical, u64 devid,
u64 **logical, int *naddrs, int *stripe_len);
int btrfs_read_sys_array(struct btrfs_root *root);
int btrfs_read_chunk_tree(struct btrfs_root *root);
int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
struct btrfs_root *extent_root, u64 type);
void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
int mirror_num, int async_submit);
int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
fmode_t flags, void *holder);
int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
struct btrfs_fs_devices **fs_devices_ret);
int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
void btrfs_close_extra_devices(struct btrfs_fs_info *fs_info,
struct btrfs_fs_devices *fs_devices, int step);
int btrfs_find_device_missing_or_by_path(struct btrfs_root *root,
char *device_path,
struct btrfs_device **device);
struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
const u64 *devid,
const u8 *uuid);
int btrfs_rm_device(struct btrfs_root *root, char *device_path);
void btrfs_cleanup_fs_uuids(void);
int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
int btrfs_grow_device(struct btrfs_trans_handle *trans,
struct btrfs_device *device, u64 new_size);
struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
u8 *uuid, u8 *fsid);
int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
int btrfs_init_new_device(struct btrfs_root *root, char *path);
int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path,
struct btrfs_device **device_out);
int btrfs_balance(struct btrfs_balance_control *bctl,
struct btrfs_ioctl_balance_args *bargs);
int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info);
int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
int find_free_dev_extent(struct btrfs_trans_handle *trans,
struct btrfs_device *device, u64 num_bytes,
u64 *start, u64 *max_avail);
void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
int btrfs_get_dev_stats(struct btrfs_root *root,
struct btrfs_ioctl_get_dev_stats *stats);
void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info);
void btrfs_rm_dev_replace_srcdev(struct btrfs_fs_info *fs_info,
struct btrfs_device *srcdev);
void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
struct btrfs_device *tgtdev);
void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
struct btrfs_device *tgtdev);
int btrfs_scratch_superblock(struct btrfs_device *device);
int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
u64 logical, u64 len, int mirror_num);
unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
struct btrfs_mapping_tree *map_tree,
u64 logical);
int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
struct btrfs_root *extent_root,
u64 chunk_offset, u64 chunk_size);
static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
int index)
{
atomic_inc(dev->dev_stat_values + index);
dev->dev_stats_dirty = 1;
}
static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
int index)
{
return atomic_read(dev->dev_stat_values + index);
}
static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
int index)
{
int ret;
ret = atomic_xchg(dev->dev_stat_values + index, 0);
dev->dev_stats_dirty = 1;
return ret;
}
static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
int index, unsigned long val)
{
atomic_set(dev->dev_stat_values + index, val);
dev->dev_stats_dirty = 1;
}
static inline void btrfs_dev_stat_reset(struct btrfs_device *dev,
int index)
{
btrfs_dev_stat_set(dev, index, 0);
}
#endif