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Diffstat (limited to 'fs/btrfs/volumes.h')
| -rw-r--r-- | fs/btrfs/volumes.h | 752 |
1 files changed, 752 insertions, 0 deletions
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h new file mode 100644 index 0000000000..2128a032c3 --- /dev/null +++ b/fs/btrfs/volumes.h @@ -0,0 +1,752 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2007 Oracle. All rights reserved. + */ + +#ifndef BTRFS_VOLUMES_H +#define BTRFS_VOLUMES_H + +#include <linux/sort.h> +#include <linux/btrfs.h> +#include "async-thread.h" +#include "messages.h" +#include "tree-checker.h" +#include "rcu-string.h" + +#define BTRFS_MAX_DATA_CHUNK_SIZE (10ULL * SZ_1G) + +extern struct mutex uuid_mutex; + +#define BTRFS_STRIPE_LEN SZ_64K +#define BTRFS_STRIPE_LEN_SHIFT (16) +#define BTRFS_STRIPE_LEN_MASK (BTRFS_STRIPE_LEN - 1) + +static_assert(const_ilog2(BTRFS_STRIPE_LEN) == BTRFS_STRIPE_LEN_SHIFT); + +/* Used by sanity check for btrfs_raid_types. */ +#define const_ffs(n) (__builtin_ctzll(n) + 1) + +/* + * The conversion from BTRFS_BLOCK_GROUP_* bits to btrfs_raid_type requires + * RAID0 always to be the lowest profile bit. + * Although it's part of on-disk format and should never change, do extra + * compile-time sanity checks. + */ +static_assert(const_ffs(BTRFS_BLOCK_GROUP_RAID0) < + const_ffs(BTRFS_BLOCK_GROUP_PROFILE_MASK & ~BTRFS_BLOCK_GROUP_RAID0)); +static_assert(const_ilog2(BTRFS_BLOCK_GROUP_RAID0) > + ilog2(BTRFS_BLOCK_GROUP_TYPE_MASK)); + +/* ilog2() can handle both constants and variables */ +#define BTRFS_BG_FLAG_TO_INDEX(profile) \ + ilog2((profile) >> (ilog2(BTRFS_BLOCK_GROUP_RAID0) - 1)) + +enum btrfs_raid_types { + /* SINGLE is the special one as it doesn't have on-disk bit. */ + BTRFS_RAID_SINGLE = 0, + + BTRFS_RAID_RAID0 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID0), + BTRFS_RAID_RAID1 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1), + BTRFS_RAID_DUP = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_DUP), + BTRFS_RAID_RAID10 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID10), + BTRFS_RAID_RAID5 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID5), + BTRFS_RAID_RAID6 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID6), + BTRFS_RAID_RAID1C3 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C3), + BTRFS_RAID_RAID1C4 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C4), + + BTRFS_NR_RAID_TYPES +}; + +/* + * 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) +#define BTRFS_DEV_STATE_NO_READA (5) + +struct btrfs_zoned_device_info; + +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 __rcu *name; + + u64 generation; + + struct block_device *bdev; + + struct btrfs_zoned_device_info *zone_info; + + /* block device holder for blkdev_get/put */ + void *holder; + + /* + * Device's major-minor number. Must be set even if the device is not + * opened (bdev == NULL), unless the device is missing. + */ + dev_t devt; + 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; + + /* Bio used for flushing device barriers */ + struct bio flush_bio; + struct completion flush_wait; + + /* per-device scrub information */ + struct scrub_ctx *scrub_ctx; + + /* 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; + + /* Bandwidth limit for scrub, in bytes */ + u64 scrub_speed_max; +}; + +/* + * Block group or device which contains an active swapfile. Used for preventing + * unsafe operations while a swapfile is active. + * + * These are sorted on (ptr, inode) (note that a block group or device can + * contain more than one swapfile). We compare the pointer values because we + * don't actually care what the object is, we just need a quick check whether + * the object exists in the rbtree. + */ +struct btrfs_swapfile_pin { + struct rb_node node; + void *ptr; + struct inode *inode; + /* + * If true, ptr points to a struct btrfs_block_group. Otherwise, ptr + * points to a struct btrfs_device. + */ + bool is_block_group; + /* + * Only used when 'is_block_group' is true and it is the number of + * extents used by a swapfile for this block group ('ptr' field). + */ + int bg_extent_count; +}; + +/* + * 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, + BTRFS_CHUNK_ALLOC_ZONED, +}; + +/* + * Read policies for mirrored block group profiles, read picks the stripe based + * on these policies. + */ +enum btrfs_read_policy { + /* Use process PID to choose the stripe */ + BTRFS_READ_POLICY_PID, + BTRFS_NR_READ_POLICY, +}; + +struct btrfs_fs_devices { + u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */ + + /* + * UUID written into the btree blocks: + * + * - If metadata_uuid != fsid then super block must have + * BTRFS_FEATURE_INCOMPAT_METADATA_UUID flag set. + * + * - Following shall be true at all times: + * - metadata_uuid == btrfs_header::fsid + * - metadata_uuid == btrfs_dev_item::fsid + */ + u8 metadata_uuid[BTRFS_FSID_SIZE]; + + struct list_head fs_list; + + /* + * Number of devices under this fsid including missing and + * replace-target device and excludes seed devices. + */ + u64 num_devices; + + /* + * The number of devices that successfully opened, including + * replace-target, excludes seed devices. + */ + u64 open_devices; + + /* The number of devices that are under the chunk allocation list. */ + u64 rw_devices; + + /* Count of missing devices under this fsid excluding seed device. */ + u64 missing_devices; + u64 total_rw_bytes; + + /* + * Count of devices from btrfs_super_block::num_devices for this fsid, + * which includes the seed device, excludes the transient replace-target + * device. + */ + u64 total_devices; + + /* Highest generation number of seen devices */ + u64 latest_generation; + + /* + * The mount device or a device with highest generation after removal + * or replace. + */ + struct btrfs_device *latest_dev; + + /* + * All of the devices in the filesystem, protected by a mutex so we can + * safely walk it to write out the super blocks without worrying about + * adding/removing by the multi-device code. Scrubbing super block 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 list_head seed_list; + + /* Count fs-devices opened. */ + int opened; + + /* Set when we find or add a device that doesn't have the nonrot flag set. */ + bool rotating; + /* Devices support TRIM/discard commands. */ + bool discardable; + bool fsid_change; + /* The filesystem is a seed filesystem. */ + bool seeding; + + 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; + + /* Policy used to read the mirrored stripes. */ + enum btrfs_read_policy read_policy; +}; + +#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) + +struct btrfs_io_stripe { + struct btrfs_device *dev; + union { + /* Block mapping */ + u64 physical; + /* For the endio handler */ + struct btrfs_io_context *bioc; + }; +}; + +struct btrfs_discard_stripe { + struct btrfs_device *dev; + u64 physical; + u64 length; +}; + +/* + * Context for IO subsmission for device stripe. + * + * - Track the unfinished mirrors for mirror based profiles + * Mirror based profiles are SINGLE/DUP/RAID1/RAID10. + * + * - Contain the logical -> physical mapping info + * Used by submit_stripe_bio() for mapping logical bio + * into physical device address. + * + * - Contain device replace info + * Used by handle_ops_on_dev_replace() to copy logical bios + * into the new device. + * + * - Contain RAID56 full stripe logical bytenrs + */ +struct btrfs_io_context { + refcount_t refs; + struct btrfs_fs_info *fs_info; + u64 map_type; /* get from map_lookup->type */ + struct bio *orig_bio; + atomic_t error; + u16 max_errors; + + /* + * The total number of stripes, including the extra duplicated + * stripe for replace. + */ + u16 num_stripes; + + /* + * The mirror_num of this bioc. + * + * This is for reads which use 0 as mirror_num, thus we should return a + * valid mirror_num (>0) for the reader. + */ + u16 mirror_num; + + /* + * The following two members are for dev-replace case only. + * + * @replace_nr_stripes: Number of duplicated stripes which need to be + * written to replace target. + * Should be <= 2 (2 for DUP, otherwise <= 1). + * @replace_stripe_src: The array indicates where the duplicated stripes + * are from. + * + * The @replace_stripe_src[] array is mostly for RAID56 cases. + * As non-RAID56 stripes share the same contents of the mapped range, + * thus no need to bother where the duplicated ones are from. + * + * But for RAID56 case, all stripes contain different contents, thus + * we need a way to know the mapping. + * + * There is an example for the two members, using a RAID5 write: + * + * num_stripes: 4 (3 + 1 duplicated write) + * stripes[0]: dev = devid 1, physical = X + * stripes[1]: dev = devid 2, physical = Y + * stripes[2]: dev = devid 3, physical = Z + * stripes[3]: dev = devid 0, physical = Y + * + * replace_nr_stripes = 1 + * replace_stripe_src = 1 <- Means stripes[1] is involved in replace. + * The duplicated stripe index would be + * (@num_stripes - 1). + * + * Note, that we can still have cases replace_nr_stripes = 2 for DUP. + * In that case, all stripes share the same content, thus we don't + * need to bother @replace_stripe_src value at all. + */ + u16 replace_nr_stripes; + s16 replace_stripe_src; + /* + * Logical bytenr of the full stripe start, only for RAID56 cases. + * + * When this value is set to other than (u64)-1, the stripes[] should + * follow this pattern: + * + * (real_stripes = num_stripes - replace_nr_stripes) + * (data_stripes = (is_raid6) ? (real_stripes - 2) : (real_stripes - 1)) + * + * stripes[0]: The first data stripe + * stripes[1]: The second data stripe + * ... + * stripes[data_stripes - 1]: The last data stripe + * stripes[data_stripes]: The P stripe + * stripes[data_stripes + 1]: The Q stripe (only for RAID6). + */ + u64 full_stripe_logical; + struct btrfs_io_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; + int num_stripes; + int sub_stripes; + int verified_stripes; /* For mount time dev extent verification */ + struct btrfs_io_stripe stripes[]; +}; + +#define map_lookup_size(n) (sizeof(struct map_lookup) + \ + (sizeof(struct btrfs_io_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; +}; + +/* + * Search for a given device by the set parameters + */ +struct btrfs_dev_lookup_args { + u64 devid; + u8 *uuid; + u8 *fsid; + bool missing; +}; + +/* We have to initialize to -1 because BTRFS_DEV_REPLACE_DEVID is 0 */ +#define BTRFS_DEV_LOOKUP_ARGS_INIT { .devid = (u64)-1 } + +#define BTRFS_DEV_LOOKUP_ARGS(name) \ + struct btrfs_dev_lookup_args name = BTRFS_DEV_LOOKUP_ARGS_INIT + +enum btrfs_map_op { + BTRFS_MAP_READ, + BTRFS_MAP_WRITE, + BTRFS_MAP_GET_READ_MIRRORS, +}; + +static inline enum btrfs_map_op btrfs_op(struct bio *bio) +{ + switch (bio_op(bio)) { + case REQ_OP_WRITE: + case REQ_OP_ZONE_APPEND: + return BTRFS_MAP_WRITE; + default: + WARN_ON_ONCE(1); + fallthrough; + case REQ_OP_READ: + return BTRFS_MAP_READ; + } +} + +static inline unsigned long btrfs_chunk_item_size(int num_stripes) +{ + ASSERT(num_stripes); + return sizeof(struct btrfs_chunk) + + sizeof(struct btrfs_stripe) * (num_stripes - 1); +} + +/* + * Do the type safe converstion from stripe_nr to offset inside the chunk. + * + * @stripe_nr is u32, with left shift it can overflow u32 for chunks larger + * than 4G. This does the proper type cast to avoid overflow. + */ +static inline u64 btrfs_stripe_nr_to_offset(u32 stripe_nr) +{ + return (u64)stripe_nr << BTRFS_STRIPE_LEN_SHIFT; +} + +void btrfs_get_bioc(struct btrfs_io_context *bioc); +void btrfs_put_bioc(struct btrfs_io_context *bioc); +int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, + u64 logical, u64 *length, + struct btrfs_io_context **bioc_ret, + struct btrfs_io_stripe *smap, int *mirror_num_ret, + int need_raid_map); +int btrfs_map_repair_block(struct btrfs_fs_info *fs_info, + struct btrfs_io_stripe *smap, u64 logical, + u32 length, int mirror_num); +struct btrfs_discard_stripe *btrfs_map_discard(struct btrfs_fs_info *fs_info, + u64 logical, u64 *length_ret, + u32 *num_stripes); +int btrfs_read_sys_array(struct btrfs_fs_info *fs_info); +int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info); +struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans, + u64 type); +void btrfs_mapping_tree_free(struct extent_map_tree *tree); +int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, + blk_mode_t flags, void *holder); +struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags); +int btrfs_forget_devices(dev_t devt); +void btrfs_close_devices(struct btrfs_fs_devices *fs_devices); +void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices); +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); +int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info, + struct btrfs_dev_lookup_args *args, + const char *path); +struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info, + const u64 *devid, const u8 *uuid, + const char *path); +void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args); +int btrfs_rm_device(struct btrfs_fs_info *fs_info, + struct btrfs_dev_lookup_args *args, + struct block_device **bdev, void **holder); +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(const struct btrfs_fs_devices *fs_devices, + const struct btrfs_dev_lookup_args *args); +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_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset); +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); +bool btrfs_chunk_writeable(struct btrfs_fs_info *fs_info, u64 chunk_offset); +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); +int 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); +u64 btrfs_calc_stripe_length(const struct extent_map *em); +int btrfs_nr_parity_stripes(u64 type); +int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans, + struct btrfs_block_group *bg); +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); +} + +static inline const char *btrfs_dev_name(const struct btrfs_device *device) +{ + if (!device || test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) + return "<missing disk>"; + else + return rcu_str_deref(device->name); +} + +void btrfs_commit_device_sizes(struct btrfs_transaction *trans); + +struct list_head * __attribute_const__ btrfs_get_fs_uuids(void); +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); + +enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags); +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); +bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical); + +bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr); +u8 *btrfs_sb_fsid_ptr(struct btrfs_super_block *sb); + +#endif |