/* SPDX-License-Identifier: GPL-2.0 */ #ifndef BTRFS_EXTENT_IO_H #define BTRFS_EXTENT_IO_H #include #include #include "ulist.h" /* * flags for bio submission. The high bits indicate the compression * type for this bio */ #define EXTENT_BIO_COMPRESSED 1 #define EXTENT_BIO_FLAG_SHIFT 16 enum { EXTENT_BUFFER_UPTODATE, EXTENT_BUFFER_DIRTY, EXTENT_BUFFER_CORRUPT, /* this got triggered by readahead */ EXTENT_BUFFER_READAHEAD, EXTENT_BUFFER_TREE_REF, EXTENT_BUFFER_STALE, EXTENT_BUFFER_WRITEBACK, /* read IO error */ EXTENT_BUFFER_READ_ERR, EXTENT_BUFFER_UNMAPPED, EXTENT_BUFFER_IN_TREE, /* write IO error */ EXTENT_BUFFER_WRITE_ERR, }; /* these are flags for __process_pages_contig */ #define PAGE_UNLOCK (1 << 0) #define PAGE_CLEAR_DIRTY (1 << 1) #define PAGE_SET_WRITEBACK (1 << 2) #define PAGE_END_WRITEBACK (1 << 3) #define PAGE_SET_PRIVATE2 (1 << 4) #define PAGE_SET_ERROR (1 << 5) #define PAGE_LOCK (1 << 6) /* * page->private values. Every page that is controlled by the extent * map has page->private set to one. */ #define EXTENT_PAGE_PRIVATE 1 /* * The extent buffer bitmap operations are done with byte granularity instead of * word granularity for two reasons: * 1. The bitmaps must be little-endian on disk. * 2. Bitmap items are not guaranteed to be aligned to a word and therefore a * single word in a bitmap may straddle two pages in the extent buffer. */ #define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE) #define BYTE_MASK ((1 << BITS_PER_BYTE) - 1) #define BITMAP_FIRST_BYTE_MASK(start) \ ((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK) #define BITMAP_LAST_BYTE_MASK(nbits) \ (BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1))) struct btrfs_root; struct btrfs_inode; struct btrfs_io_bio; struct io_failure_record; struct extent_io_tree; typedef blk_status_t (extent_submit_bio_start_t)(void *private_data, struct bio *bio, u64 bio_offset); struct extent_io_ops { /* * The following callbacks must be always defined, the function * pointer will be called unconditionally. */ blk_status_t (*submit_bio_hook)(struct inode *inode, struct bio *bio, int mirror_num, unsigned long bio_flags); int (*readpage_end_io_hook)(struct btrfs_io_bio *io_bio, u64 phy_offset, struct page *page, u64 start, u64 end, int mirror); }; #define INLINE_EXTENT_BUFFER_PAGES 16 #define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_SIZE) struct extent_buffer { u64 start; unsigned long len; unsigned long bflags; struct btrfs_fs_info *fs_info; spinlock_t refs_lock; atomic_t refs; atomic_t io_pages; int read_mirror; struct rcu_head rcu_head; pid_t lock_owner; int blocking_writers; atomic_t blocking_readers; bool lock_nested; /* >= 0 if eb belongs to a log tree, -1 otherwise */ short log_index; /* protects write locks */ rwlock_t lock; /* readers use lock_wq while they wait for the write * lock holders to unlock */ wait_queue_head_t write_lock_wq; /* writers use read_lock_wq while they wait for readers * to unlock */ wait_queue_head_t read_lock_wq; struct page *pages[INLINE_EXTENT_BUFFER_PAGES]; #ifdef CONFIG_BTRFS_DEBUG int spinning_writers; atomic_t spinning_readers; atomic_t read_locks; int write_locks; struct list_head leak_list; #endif }; /* * Structure to record how many bytes and which ranges are set/cleared */ struct extent_changeset { /* How many bytes are set/cleared in this operation */ unsigned int bytes_changed; /* Changed ranges */ struct ulist range_changed; }; static inline void extent_changeset_init(struct extent_changeset *changeset) { changeset->bytes_changed = 0; ulist_init(&changeset->range_changed); } static inline struct extent_changeset *extent_changeset_alloc(void) { struct extent_changeset *ret; ret = kmalloc(sizeof(*ret), GFP_KERNEL); if (!ret) return NULL; extent_changeset_init(ret); return ret; } static inline void extent_changeset_release(struct extent_changeset *changeset) { if (!changeset) return; changeset->bytes_changed = 0; ulist_release(&changeset->range_changed); } static inline void extent_changeset_free(struct extent_changeset *changeset) { if (!changeset) return; extent_changeset_release(changeset); kfree(changeset); } static inline void extent_set_compress_type(unsigned long *bio_flags, int compress_type) { *bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT; } static inline int extent_compress_type(unsigned long bio_flags) { return bio_flags >> EXTENT_BIO_FLAG_SHIFT; } struct extent_map_tree; typedef struct extent_map *(get_extent_t)(struct btrfs_inode *inode, struct page *page, size_t pg_offset, u64 start, u64 len, int create); int try_release_extent_mapping(struct page *page, gfp_t mask); int try_release_extent_buffer(struct page *page); int extent_read_full_page(struct extent_io_tree *tree, struct page *page, get_extent_t *get_extent, int mirror_num); int extent_write_full_page(struct page *page, struct writeback_control *wbc); int extent_write_locked_range(struct inode *inode, u64 start, u64 end, int mode); int extent_writepages(struct address_space *mapping, struct writeback_control *wbc); int btree_write_cache_pages(struct address_space *mapping, struct writeback_control *wbc); int extent_readpages(struct address_space *mapping, struct list_head *pages, unsigned nr_pages); int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, __u64 start, __u64 len); void set_page_extent_mapped(struct page *page); struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info, u64 start); struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info, u64 start, unsigned long len); struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info, u64 start); struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src); struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info, u64 start); void free_extent_buffer(struct extent_buffer *eb); void free_extent_buffer_stale(struct extent_buffer *eb); #define WAIT_NONE 0 #define WAIT_COMPLETE 1 #define WAIT_PAGE_LOCK 2 int read_extent_buffer_pages(struct extent_buffer *eb, int wait, int mirror_num); void wait_on_extent_buffer_writeback(struct extent_buffer *eb); static inline int num_extent_pages(const struct extent_buffer *eb) { return (round_up(eb->start + eb->len, PAGE_SIZE) >> PAGE_SHIFT) - (eb->start >> PAGE_SHIFT); } static inline void extent_buffer_get(struct extent_buffer *eb) { atomic_inc(&eb->refs); } static inline int extent_buffer_uptodate(struct extent_buffer *eb) { return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); } int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv, unsigned long start, unsigned long len); void read_extent_buffer(const struct extent_buffer *eb, void *dst, unsigned long start, unsigned long len); int read_extent_buffer_to_user(const struct extent_buffer *eb, void __user *dst, unsigned long start, unsigned long len); void write_extent_buffer_fsid(struct extent_buffer *eb, const void *src); void write_extent_buffer_chunk_tree_uuid(struct extent_buffer *eb, const void *src); void write_extent_buffer(struct extent_buffer *eb, const void *src, unsigned long start, unsigned long len); void copy_extent_buffer_full(struct extent_buffer *dst, struct extent_buffer *src); void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, unsigned long dst_offset, unsigned long src_offset, unsigned long len); void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, unsigned long src_offset, unsigned long len); void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, unsigned long src_offset, unsigned long len); void memzero_extent_buffer(struct extent_buffer *eb, unsigned long start, unsigned long len); int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start, unsigned long pos); void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start, unsigned long pos, unsigned long len); void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start, unsigned long pos, unsigned long len); void clear_extent_buffer_dirty(struct extent_buffer *eb); bool set_extent_buffer_dirty(struct extent_buffer *eb); void set_extent_buffer_uptodate(struct extent_buffer *eb); void clear_extent_buffer_uptodate(struct extent_buffer *eb); int extent_buffer_under_io(struct extent_buffer *eb); int map_private_extent_buffer(const struct extent_buffer *eb, unsigned long offset, unsigned long min_len, char **map, unsigned long *map_start, unsigned long *map_len); void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end); void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end); void extent_clear_unlock_delalloc(struct inode *inode, u64 start, u64 end, struct page *locked_page, unsigned bits_to_clear, unsigned long page_ops); struct bio *btrfs_bio_alloc(u64 first_byte); struct bio *btrfs_io_bio_alloc(unsigned int nr_iovecs); struct bio *btrfs_bio_clone(struct bio *bio); struct bio *btrfs_bio_clone_partial(struct bio *orig, int offset, int size); struct btrfs_fs_info; struct btrfs_inode; int repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start, u64 length, u64 logical, struct page *page, unsigned int pg_offset, int mirror_num); void end_extent_writepage(struct page *page, int err, u64 start, u64 end); int btrfs_repair_eb_io_failure(struct extent_buffer *eb, int mirror_num); /* * When IO fails, either with EIO or csum verification fails, we * try other mirrors that might have a good copy of the data. This * io_failure_record is used to record state as we go through all the * mirrors. If another mirror has good data, the page is set up to date * and things continue. If a good mirror can't be found, the original * bio end_io callback is called to indicate things have failed. */ struct io_failure_record { struct page *page; u64 start; u64 len; u64 logical; unsigned long bio_flags; int this_mirror; int failed_mirror; int in_validation; }; bool btrfs_check_repairable(struct inode *inode, unsigned failed_bio_pages, struct io_failure_record *failrec, int fail_mirror); struct bio *btrfs_create_repair_bio(struct inode *inode, struct bio *failed_bio, struct io_failure_record *failrec, struct page *page, int pg_offset, int icsum, bio_end_io_t *endio_func, void *data); #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS bool find_lock_delalloc_range(struct inode *inode, struct page *locked_page, u64 *start, u64 *end); #endif struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info, u64 start); #endif