diff options
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/blk_types.h | 8 | ||||
-rw-r--r-- | include/linux/blkdev.h | 29 | ||||
-rw-r--r-- | include/linux/fs.h | 19 |
3 files changed, 41 insertions, 15 deletions
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index b29ebd53417d..7c2316c91cbd 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -57,20 +57,18 @@ struct block_device { void * bd_holder; const struct blk_holder_ops *bd_holder_ops; struct mutex bd_holder_lock; - /* The counter of freeze processes */ - int bd_fsfreeze_count; int bd_holders; struct kobject *bd_holder_dir; - /* Mutex for freeze */ - struct mutex bd_fsfreeze_mutex; - struct super_block *bd_fsfreeze_sb; + atomic_t bd_fsfreeze_count; /* number of freeze requests */ + struct mutex bd_fsfreeze_mutex; /* serialize freeze/thaw */ struct partition_meta_info *bd_meta_info; #ifdef CONFIG_FAIL_MAKE_REQUEST bool bd_make_it_fail; #endif bool bd_ro_warned; + int bd_writers; /* * keep this out-of-line as it's both big and not needed in the fast * path diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 88e9dd4b71fb..c30a98e08423 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -124,6 +124,8 @@ typedef unsigned int __bitwise blk_mode_t; #define BLK_OPEN_NDELAY ((__force blk_mode_t)(1 << 3)) /* open for "writes" only for ioctls (specialy hack for floppy.c) */ #define BLK_OPEN_WRITE_IOCTL ((__force blk_mode_t)(1 << 4)) +/* open is exclusive wrt all other BLK_OPEN_WRITE opens to the device */ +#define BLK_OPEN_RESTRICT_WRITES ((__force blk_mode_t)(1 << 5)) struct gendisk { /* @@ -1468,8 +1470,23 @@ struct blk_holder_ops { * Sync the file system mounted on the block device. */ void (*sync)(struct block_device *bdev); + + /* + * Freeze the file system mounted on the block device. + */ + int (*freeze)(struct block_device *bdev); + + /* + * Thaw the file system mounted on the block device. + */ + int (*thaw)(struct block_device *bdev); }; +/* + * For filesystems using @fs_holder_ops, the @holder argument passed to + * helpers used to open and claim block devices via + * bd_prepare_to_claim() must point to a superblock. + */ extern const struct blk_holder_ops fs_holder_ops; /* @@ -1477,7 +1494,8 @@ extern const struct blk_holder_ops fs_holder_ops; * as stored in sb->s_flags. */ #define sb_open_mode(flags) \ - (BLK_OPEN_READ | (((flags) & SB_RDONLY) ? 0 : BLK_OPEN_WRITE)) + (BLK_OPEN_READ | BLK_OPEN_RESTRICT_WRITES | \ + (((flags) & SB_RDONLY) ? 0 : BLK_OPEN_WRITE)) struct bdev_handle { struct block_device *bdev; @@ -1485,10 +1503,6 @@ struct bdev_handle { blk_mode_t mode; }; -struct block_device *blkdev_get_by_dev(dev_t dev, blk_mode_t mode, void *holder, - const struct blk_holder_ops *hops); -struct block_device *blkdev_get_by_path(const char *path, blk_mode_t mode, - void *holder, const struct blk_holder_ops *hops); struct bdev_handle *bdev_open_by_dev(dev_t dev, blk_mode_t mode, void *holder, const struct blk_holder_ops *hops); struct bdev_handle *bdev_open_by_path(const char *path, blk_mode_t mode, @@ -1496,7 +1510,6 @@ struct bdev_handle *bdev_open_by_path(const char *path, blk_mode_t mode, int bd_prepare_to_claim(struct block_device *bdev, void *holder, const struct blk_holder_ops *hops); void bd_abort_claiming(struct block_device *bdev, void *holder); -void blkdev_put(struct block_device *bdev, void *holder); void bdev_release(struct bdev_handle *handle); /* just for blk-cgroup, don't use elsewhere */ @@ -1541,8 +1554,8 @@ static inline int early_lookup_bdev(const char *pathname, dev_t *dev) } #endif /* CONFIG_BLOCK */ -int freeze_bdev(struct block_device *bdev); -int thaw_bdev(struct block_device *bdev); +int bdev_freeze(struct block_device *bdev); +int bdev_thaw(struct block_device *bdev); struct io_comp_batch { struct request *req_list; diff --git a/include/linux/fs.h b/include/linux/fs.h index 3d58376ed39e..7e7399bd8bc5 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1187,7 +1187,8 @@ enum { struct sb_writers { unsigned short frozen; /* Is sb frozen? */ - unsigned short freeze_holders; /* Who froze fs? */ + int freeze_kcount; /* How many kernel freeze requests? */ + int freeze_ucount; /* How many userspace freeze requests? */ struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS]; }; @@ -2053,9 +2054,24 @@ extern loff_t vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos, struct file *dst_file, loff_t dst_pos, loff_t len, unsigned int remap_flags); +/** + * enum freeze_holder - holder of the freeze + * @FREEZE_HOLDER_KERNEL: kernel wants to freeze or thaw filesystem + * @FREEZE_HOLDER_USERSPACE: userspace wants to freeze or thaw filesystem + * @FREEZE_MAY_NEST: whether nesting freeze and thaw requests is allowed + * + * Indicate who the owner of the freeze or thaw request is and whether + * the freeze needs to be exclusive or can nest. + * Without @FREEZE_MAY_NEST, multiple freeze and thaw requests from the + * same holder aren't allowed. It is however allowed to hold a single + * @FREEZE_HOLDER_USERSPACE and a single @FREEZE_HOLDER_KERNEL freeze at + * the same time. This is relied upon by some filesystems during online + * repair or similar. + */ enum freeze_holder { FREEZE_HOLDER_KERNEL = (1U << 0), FREEZE_HOLDER_USERSPACE = (1U << 1), + FREEZE_MAY_NEST = (1U << 2), }; struct super_operations { @@ -3131,7 +3147,6 @@ extern int vfs_readlink(struct dentry *, char __user *, int); extern struct file_system_type *get_filesystem(struct file_system_type *fs); extern void put_filesystem(struct file_system_type *fs); extern struct file_system_type *get_fs_type(const char *name); -extern struct super_block *get_active_super(struct block_device *bdev); extern void drop_super(struct super_block *sb); extern void drop_super_exclusive(struct super_block *sb); extern void iterate_supers(void (*)(struct super_block *, void *), void *); |