https://github.com/torvalds/linux
Tip revision: bbf5c979011a099af5dc76498918ed7df445635b authored by Linus Torvalds on 11 October 2020, 21:15:50 UTC
Linux 5.9
Linux 5.9
Tip revision: bbf5c97
volumes.h
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2007 Oracle. All rights reserved.
*/
#ifndef BTRFS_VOLUMES_H
#define BTRFS_VOLUMES_H
#include <linux/bio.h>
#include <linux/sort.h>
#include <linux/btrfs.h>
#include "async-thread.h"
#define BTRFS_MAX_DATA_CHUNK_SIZE (10ULL * SZ_1G)
extern struct mutex uuid_mutex;
#define BTRFS_STRIPE_LEN SZ_64K
struct btrfs_io_geometry {
/* remaining bytes before crossing a stripe */
u64 len;
/* offset of logical address in chunk */
u64 offset;
/* length of single IO stripe */
u64 stripe_len;
/* number of stripe where address falls */
u64 stripe_nr;
/* offset of address in stripe */
u64 stripe_offset;
/* offset of raid56 stripe into the chunk */
u64 raid56_stripe_offset;
};
/*
* Use sequence counter to get consistent device stat data on
* 32-bit processors.
*/
#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
#include <linux/seqlock.h>
#define __BTRFS_NEED_DEVICE_DATA_ORDERED
#define btrfs_device_data_ordered_init(device) \
seqcount_init(&device->data_seqcount)
#else
#define btrfs_device_data_ordered_init(device) do { } while (0)
#endif
#define BTRFS_DEV_STATE_WRITEABLE (0)
#define BTRFS_DEV_STATE_IN_FS_METADATA (1)
#define BTRFS_DEV_STATE_MISSING (2)
#define BTRFS_DEV_STATE_REPLACE_TGT (3)
#define BTRFS_DEV_STATE_FLUSH_SENT (4)
struct btrfs_device {
struct list_head dev_list; /* device_list_mutex */
struct list_head dev_alloc_list; /* chunk mutex */
struct list_head post_commit_list; /* chunk mutex */
struct btrfs_fs_devices *fs_devices;
struct btrfs_fs_info *fs_info;
struct rcu_string *name;
u64 generation;
struct block_device *bdev;
/* the mode sent to blkdev_get */
fmode_t mode;
unsigned long dev_state;
blk_status_t last_flush_error;
#ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
seqcount_t data_seqcount;
#endif
/* the internal btrfs device id */
u64 devid;
/* size of the device in memory */
u64 total_bytes;
/* size of the device on 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];
/*
* size of the device on the current transaction
*
* This variant is update when committing the transaction,
* and protected by chunk mutex
*/
u64 commit_total_bytes;
/* bytes used on the current transaction */
u64 commit_bytes_used;
/* for sending down flush barriers */
struct bio *flush_bio;
struct completion flush_wait;
/* per-device scrub information */
struct scrub_ctx *scrub_ctx;
/* readahead state */
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;
/* Counter to record the change of device stats */
atomic_t dev_stats_ccnt;
atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
struct extent_io_tree alloc_state;
struct completion kobj_unregister;
/* For sysfs/FSID/devinfo/devid/ */
struct kobject devid_kobj;
};
/*
* If we read those variants at the context of their own lock, we needn't
* use the following helpers, reading them directly is safe.
*/
#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
#define BTRFS_DEVICE_GETSET_FUNCS(name) \
static inline u64 \
btrfs_device_get_##name(const struct btrfs_device *dev) \
{ \
u64 size; \
unsigned int seq; \
\
do { \
seq = read_seqcount_begin(&dev->data_seqcount); \
size = dev->name; \
} while (read_seqcount_retry(&dev->data_seqcount, seq)); \
return size; \
} \
\
static inline void \
btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
{ \
preempt_disable(); \
write_seqcount_begin(&dev->data_seqcount); \
dev->name = size; \
write_seqcount_end(&dev->data_seqcount); \
preempt_enable(); \
}
#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
#define BTRFS_DEVICE_GETSET_FUNCS(name) \
static inline u64 \
btrfs_device_get_##name(const struct btrfs_device *dev) \
{ \
u64 size; \
\
preempt_disable(); \
size = dev->name; \
preempt_enable(); \
return size; \
} \
\
static inline void \
btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
{ \
preempt_disable(); \
dev->name = size; \
preempt_enable(); \
}
#else
#define BTRFS_DEVICE_GETSET_FUNCS(name) \
static inline u64 \
btrfs_device_get_##name(const struct btrfs_device *dev) \
{ \
return dev->name; \
} \
\
static inline void \
btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \
{ \
dev->name = size; \
}
#endif
BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
enum btrfs_chunk_allocation_policy {
BTRFS_CHUNK_ALLOC_REGULAR,
};
struct btrfs_fs_devices {
u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
u8 metadata_uuid[BTRFS_FSID_SIZE];
bool fsid_change;
struct list_head fs_list;
u64 num_devices;
u64 open_devices;
u64 rw_devices;
u64 missing_devices;
u64 total_rw_bytes;
u64 total_devices;
/* Highest generation number of seen devices */
u64 latest_generation;
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;
/* List of all devices, protected by device_list_mutex */
struct list_head devices;
/*
* Devices which can satisfy space allocation. Protected by
* chunk_mutex
*/
struct list_head alloc_list;
struct btrfs_fs_devices *seed;
bool seeding;
int opened;
/* set when we find or add a device that doesn't have the
* nonrot flag set
*/
bool rotating;
struct btrfs_fs_info *fs_info;
/* sysfs kobjects */
struct kobject fsid_kobj;
struct kobject *devices_kobj;
struct kobject *devinfo_kobj;
struct completion kobj_unregister;
enum btrfs_chunk_allocation_policy chunk_alloc_policy;
};
#define BTRFS_BIO_INLINE_CSUM_SIZE 64
#define BTRFS_MAX_DEVS(info) ((BTRFS_MAX_ITEM_SIZE(info) \
- sizeof(struct btrfs_chunk)) \
/ sizeof(struct btrfs_stripe) + 1)
#define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE \
- 2 * sizeof(struct btrfs_disk_key) \
- 2 * sizeof(struct btrfs_chunk)) \
/ sizeof(struct btrfs_stripe) + 1)
/*
* 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.
*/
struct btrfs_io_bio {
unsigned int mirror_num;
struct btrfs_device *device;
u64 logical;
u8 *csum;
u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
struct bvec_iter iter;
/*
* This member must come last, bio_alloc_bioset will allocate enough
* bytes for entire btrfs_io_bio but relies on bio being last.
*/
struct bio bio;
};
static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
{
return container_of(bio, struct btrfs_io_bio, bio);
}
static inline void btrfs_io_bio_free_csum(struct btrfs_io_bio *io_bio)
{
if (io_bio->csum != io_bio->csum_inline) {
kfree(io_bio->csum);
io_bio->csum = NULL;
}
}
struct btrfs_bio_stripe {
struct btrfs_device *dev;
u64 physical;
u64 length; /* only used for discard mappings */
};
struct btrfs_bio {
refcount_t refs;
atomic_t stripes_pending;
struct btrfs_fs_info *fs_info;
u64 map_type; /* get from map_lookup->type */
bio_end_io_t *end_io;
struct bio *orig_bio;
void *private;
atomic_t error;
int max_errors;
int num_stripes;
int mirror_num;
int num_tgtdevs;
int *tgtdev_map;
/*
* logical block numbers for the start of each stripe
* The last one or two are p/q. These are sorted,
* so raid_map[0] is the start of our full stripe
*/
u64 *raid_map;
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 {
u8 sub_stripes; /* sub_stripes info for map */
u8 dev_stripes; /* stripes per dev */
u8 devs_max; /* max devs to use */
u8 devs_min; /* min devs needed */
u8 tolerated_failures; /* max tolerated fail devs */
u8 devs_increment; /* ndevs has to be a multiple of this */
u8 ncopies; /* how many copies to data has */
u8 nparity; /* number of stripes worth of bytes to store
* parity information */
u8 mindev_error; /* error code if min devs requisite is unmet */
const char raid_name[8]; /* name of the raid */
u64 bg_flag; /* block group flag of the raid */
};
extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];
struct map_lookup {
u64 type;
int io_align;
int io_width;
u64 stripe_len;
int num_stripes;
int sub_stripes;
int verified_stripes; /* For mount time dev extent verification */
struct btrfs_bio_stripe stripes[];
};
#define map_lookup_size(n) (sizeof(struct map_lookup) + \
(sizeof(struct btrfs_bio_stripe) * (n)))
struct btrfs_balance_args;
struct btrfs_balance_progress;
struct btrfs_balance_control {
struct btrfs_balance_args data;
struct btrfs_balance_args meta;
struct btrfs_balance_args sys;
u64 flags;
struct btrfs_balance_progress stat;
};
enum btrfs_map_op {
BTRFS_MAP_READ,
BTRFS_MAP_WRITE,
BTRFS_MAP_DISCARD,
BTRFS_MAP_GET_READ_MIRRORS,
};
static inline enum btrfs_map_op btrfs_op(struct bio *bio)
{
switch (bio_op(bio)) {
case REQ_OP_DISCARD:
return BTRFS_MAP_DISCARD;
case REQ_OP_WRITE:
return BTRFS_MAP_WRITE;
default:
WARN_ON_ONCE(1);
fallthrough;
case REQ_OP_READ:
return BTRFS_MAP_READ;
}
}
void btrfs_get_bbio(struct btrfs_bio *bbio);
void btrfs_put_bbio(struct btrfs_bio *bbio);
int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
u64 logical, u64 *length,
struct btrfs_bio **bbio_ret, int mirror_num);
int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
u64 logical, u64 *length,
struct btrfs_bio **bbio_ret);
int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
u64 logical, u64 len, struct btrfs_io_geometry *io_geom);
int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, u64 type);
void btrfs_mapping_tree_free(struct extent_map_tree *tree);
blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
int mirror_num);
int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
fmode_t flags, void *holder);
struct btrfs_device *btrfs_scan_one_device(const char *path,
fmode_t flags, void *holder);
int btrfs_forget_devices(const char *path);
int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices, int step);
void btrfs_assign_next_active_device(struct btrfs_device *device,
struct btrfs_device *this_dev);
struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,
u64 devid,
const char *devpath);
struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
const u64 *devid,
const u8 *uuid);
void btrfs_free_device(struct btrfs_device *device);
int btrfs_rm_device(struct btrfs_fs_info *fs_info,
const char *device_path, u64 devid);
void __exit 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_devices *fs_devices,
u64 devid, u8 *uuid, u8 *fsid, bool seed);
int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path);
int btrfs_balance(struct btrfs_fs_info *fs_info,
struct btrfs_balance_control *bctl,
struct btrfs_ioctl_balance_args *bargs);
void btrfs_describe_block_groups(u64 flags, char *buf, u32 size_buf);
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_uuid_scan_kthread(void *data);
int btrfs_chunk_readonly(struct btrfs_fs_info *fs_info, u64 chunk_offset);
int find_free_dev_extent(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_fs_info *fs_info,
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);
void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev);
void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev);
void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev);
int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,
u64 logical, u64 len);
unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
u64 logical);
int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
u64 chunk_offset, u64 chunk_size);
int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);
struct extent_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
u64 logical, u64 length);
void btrfs_release_disk_super(struct btrfs_super_block *super);
static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
int index)
{
atomic_inc(dev->dev_stat_values + index);
/*
* This memory barrier orders stores updating statistics before stores
* updating dev_stats_ccnt.
*
* It pairs with smp_rmb() in btrfs_run_dev_stats().
*/
smp_mb__before_atomic();
atomic_inc(&dev->dev_stats_ccnt);
}
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);
/*
* atomic_xchg implies a full memory barriers as per atomic_t.txt:
* - RMW operations that have a return value are fully ordered;
*
* This implicit memory barriers is paired with the smp_rmb in
* btrfs_run_dev_stats
*/
atomic_inc(&dev->dev_stats_ccnt);
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);
/*
* This memory barrier orders stores updating statistics before stores
* updating dev_stats_ccnt.
*
* It pairs with smp_rmb() in btrfs_run_dev_stats().
*/
smp_mb__before_atomic();
atomic_inc(&dev->dev_stats_ccnt);
}
/*
* Convert block group flags (BTRFS_BLOCK_GROUP_*) to btrfs_raid_types, which
* can be used as index to access btrfs_raid_array[].
*/
static inline enum btrfs_raid_types btrfs_bg_flags_to_raid_index(u64 flags)
{
if (flags & BTRFS_BLOCK_GROUP_RAID10)
return BTRFS_RAID_RAID10;
else if (flags & BTRFS_BLOCK_GROUP_RAID1)
return BTRFS_RAID_RAID1;
else if (flags & BTRFS_BLOCK_GROUP_RAID1C3)
return BTRFS_RAID_RAID1C3;
else if (flags & BTRFS_BLOCK_GROUP_RAID1C4)
return BTRFS_RAID_RAID1C4;
else if (flags & BTRFS_BLOCK_GROUP_DUP)
return BTRFS_RAID_DUP;
else if (flags & BTRFS_BLOCK_GROUP_RAID0)
return BTRFS_RAID_RAID0;
else if (flags & BTRFS_BLOCK_GROUP_RAID5)
return BTRFS_RAID_RAID5;
else if (flags & BTRFS_BLOCK_GROUP_RAID6)
return BTRFS_RAID_RAID6;
return BTRFS_RAID_SINGLE; /* BTRFS_BLOCK_GROUP_SINGLE */
}
void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
struct list_head * __attribute_const__ btrfs_get_fs_uuids(void);
void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info);
void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info);
bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
struct btrfs_device *failing_dev);
void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info,
struct block_device *bdev,
const char *device_path);
int btrfs_bg_type_to_factor(u64 flags);
const char *btrfs_bg_type_to_raid_name(u64 flags);
int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
#endif