1 /* SPDX-License-Identifier: GPL-2.0 */
3 #ifndef BTRFS_EXTENT_IO_H
4 #define BTRFS_EXTENT_IO_H
6 #include <linux/rbtree.h>
7 #include <linux/refcount.h>
8 #include <linux/fiemap.h>
9 #include <linux/btrfs_tree.h>
13 * flags for bio submission. The high bits indicate the compression
16 #define EXTENT_BIO_COMPRESSED 1
17 #define EXTENT_BIO_FLAG_SHIFT 16
20 EXTENT_BUFFER_UPTODATE,
22 EXTENT_BUFFER_CORRUPT,
23 /* this got triggered by readahead */
24 EXTENT_BUFFER_READAHEAD,
25 EXTENT_BUFFER_TREE_REF,
27 EXTENT_BUFFER_WRITEBACK,
29 EXTENT_BUFFER_READ_ERR,
30 EXTENT_BUFFER_UNMAPPED,
31 EXTENT_BUFFER_IN_TREE,
33 EXTENT_BUFFER_WRITE_ERR,
36 /* these are flags for __process_pages_contig */
37 #define PAGE_UNLOCK (1 << 0)
38 #define PAGE_CLEAR_DIRTY (1 << 1)
39 #define PAGE_SET_WRITEBACK (1 << 2)
40 #define PAGE_END_WRITEBACK (1 << 3)
41 #define PAGE_SET_PRIVATE2 (1 << 4)
42 #define PAGE_SET_ERROR (1 << 5)
43 #define PAGE_LOCK (1 << 6)
46 * page->private values. Every page that is controlled by the extent
47 * map has page->private set to one.
49 #define EXTENT_PAGE_PRIVATE 1
52 * The extent buffer bitmap operations are done with byte granularity instead of
53 * word granularity for two reasons:
54 * 1. The bitmaps must be little-endian on disk.
55 * 2. Bitmap items are not guaranteed to be aligned to a word and therefore a
56 * single word in a bitmap may straddle two pages in the extent buffer.
58 #define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE)
59 #define BYTE_MASK ((1 << BITS_PER_BYTE) - 1)
60 #define BITMAP_FIRST_BYTE_MASK(start) \
61 ((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK)
62 #define BITMAP_LAST_BYTE_MASK(nbits) \
63 (BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1)))
68 struct io_failure_record;
69 struct extent_io_tree;
71 typedef blk_status_t (submit_bio_hook_t)(struct inode *inode, struct bio *bio,
73 unsigned long bio_flags);
75 typedef blk_status_t (extent_submit_bio_start_t)(struct inode *inode,
76 struct bio *bio, u64 dio_file_offset);
78 #define INLINE_EXTENT_BUFFER_PAGES (BTRFS_MAX_METADATA_BLOCKSIZE / PAGE_SIZE)
79 struct extent_buffer {
83 struct btrfs_fs_info *fs_info;
88 struct rcu_head rcu_head;
90 /* >= 0 if eb belongs to a log tree, -1 otherwise */
93 struct rw_semaphore lock;
95 struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
96 #ifdef CONFIG_BTRFS_DEBUG
97 struct list_head leak_list;
102 * Structure to record how many bytes and which ranges are set/cleared
104 struct extent_changeset {
105 /* How many bytes are set/cleared in this operation */
106 unsigned int bytes_changed;
109 struct ulist range_changed;
112 static inline void extent_changeset_init(struct extent_changeset *changeset)
114 changeset->bytes_changed = 0;
115 ulist_init(&changeset->range_changed);
118 static inline struct extent_changeset *extent_changeset_alloc(void)
120 struct extent_changeset *ret;
122 ret = kmalloc(sizeof(*ret), GFP_KERNEL);
126 extent_changeset_init(ret);
130 static inline void extent_changeset_release(struct extent_changeset *changeset)
134 changeset->bytes_changed = 0;
135 ulist_release(&changeset->range_changed);
138 static inline void extent_changeset_free(struct extent_changeset *changeset)
142 extent_changeset_release(changeset);
146 static inline void extent_set_compress_type(unsigned long *bio_flags,
149 *bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT;
152 static inline int extent_compress_type(unsigned long bio_flags)
154 return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
157 struct extent_map_tree;
159 typedef struct extent_map *(get_extent_t)(struct btrfs_inode *inode,
160 struct page *page, size_t pg_offset,
163 int try_release_extent_mapping(struct page *page, gfp_t mask);
164 int try_release_extent_buffer(struct page *page);
166 int __must_check submit_one_bio(struct bio *bio, int mirror_num,
167 unsigned long bio_flags);
168 int btrfs_do_readpage(struct page *page, struct extent_map **em_cached,
169 struct bio **bio, unsigned long *bio_flags,
170 unsigned int read_flags, u64 *prev_em_start);
171 int extent_write_full_page(struct page *page, struct writeback_control *wbc);
172 int extent_write_locked_range(struct inode *inode, u64 start, u64 end,
174 int extent_writepages(struct address_space *mapping,
175 struct writeback_control *wbc);
176 int btree_write_cache_pages(struct address_space *mapping,
177 struct writeback_control *wbc);
178 void extent_readahead(struct readahead_control *rac);
179 int extent_fiemap(struct btrfs_inode *inode, struct fiemap_extent_info *fieinfo,
181 void set_page_extent_mapped(struct page *page);
183 struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
184 u64 start, u64 owner_root, int level);
185 struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
186 u64 start, unsigned long len);
187 struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
189 struct extent_buffer *btrfs_clone_extent_buffer(const struct extent_buffer *src);
190 struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
192 void free_extent_buffer(struct extent_buffer *eb);
193 void free_extent_buffer_stale(struct extent_buffer *eb);
195 #define WAIT_COMPLETE 1
196 #define WAIT_PAGE_LOCK 2
197 int read_extent_buffer_pages(struct extent_buffer *eb, int wait,
199 void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
200 void btrfs_readahead_tree_block(struct btrfs_fs_info *fs_info,
201 u64 bytenr, u64 owner_root, u64 gen, int level);
202 void btrfs_readahead_node_child(struct extent_buffer *node, int slot);
204 static inline int num_extent_pages(const struct extent_buffer *eb)
207 * For sectorsize == PAGE_SIZE case, since nodesize is always aligned to
208 * sectorsize, it's just eb->len >> PAGE_SHIFT.
210 * For sectorsize < PAGE_SIZE case, we could have nodesize < PAGE_SIZE,
211 * thus have to ensure we get at least one page.
213 return (eb->len >> PAGE_SHIFT) ?: 1;
216 static inline int extent_buffer_uptodate(const struct extent_buffer *eb)
218 return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
221 int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv,
222 unsigned long start, unsigned long len);
223 void read_extent_buffer(const struct extent_buffer *eb, void *dst,
226 int read_extent_buffer_to_user_nofault(const struct extent_buffer *eb,
227 void __user *dst, unsigned long start,
229 void write_extent_buffer_fsid(const struct extent_buffer *eb, const void *src);
230 void write_extent_buffer_chunk_tree_uuid(const struct extent_buffer *eb,
232 void write_extent_buffer(const struct extent_buffer *eb, const void *src,
233 unsigned long start, unsigned long len);
234 void copy_extent_buffer_full(const struct extent_buffer *dst,
235 const struct extent_buffer *src);
236 void copy_extent_buffer(const struct extent_buffer *dst,
237 const struct extent_buffer *src,
238 unsigned long dst_offset, unsigned long src_offset,
240 void memcpy_extent_buffer(const struct extent_buffer *dst,
241 unsigned long dst_offset, unsigned long src_offset,
243 void memmove_extent_buffer(const struct extent_buffer *dst,
244 unsigned long dst_offset, unsigned long src_offset,
246 void memzero_extent_buffer(const struct extent_buffer *eb, unsigned long start,
248 int extent_buffer_test_bit(const struct extent_buffer *eb, unsigned long start,
250 void extent_buffer_bitmap_set(const struct extent_buffer *eb, unsigned long start,
251 unsigned long pos, unsigned long len);
252 void extent_buffer_bitmap_clear(const struct extent_buffer *eb,
253 unsigned long start, unsigned long pos,
255 void clear_extent_buffer_dirty(const struct extent_buffer *eb);
256 bool set_extent_buffer_dirty(struct extent_buffer *eb);
257 void set_extent_buffer_uptodate(struct extent_buffer *eb);
258 void clear_extent_buffer_uptodate(struct extent_buffer *eb);
259 int extent_buffer_under_io(const struct extent_buffer *eb);
260 void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
261 void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
262 void extent_clear_unlock_delalloc(struct btrfs_inode *inode, u64 start, u64 end,
263 struct page *locked_page,
264 u32 bits_to_clear, unsigned long page_ops);
265 struct bio *btrfs_bio_alloc(u64 first_byte);
266 struct bio *btrfs_io_bio_alloc(unsigned int nr_iovecs);
267 struct bio *btrfs_bio_clone(struct bio *bio);
268 struct bio *btrfs_bio_clone_partial(struct bio *orig, int offset, int size);
270 struct btrfs_fs_info;
273 int repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start,
274 u64 length, u64 logical, struct page *page,
275 unsigned int pg_offset, int mirror_num);
276 void end_extent_writepage(struct page *page, int err, u64 start, u64 end);
277 int btrfs_repair_eb_io_failure(const struct extent_buffer *eb, int mirror_num);
280 * When IO fails, either with EIO or csum verification fails, we
281 * try other mirrors that might have a good copy of the data. This
282 * io_failure_record is used to record state as we go through all the
283 * mirrors. If another mirror has good data, the page is set up to date
284 * and things continue. If a good mirror can't be found, the original
285 * bio end_io callback is called to indicate things have failed.
287 struct io_failure_record {
292 unsigned long bio_flags;
299 blk_status_t btrfs_submit_read_repair(struct inode *inode,
300 struct bio *failed_bio, u32 bio_offset,
301 struct page *page, unsigned int pgoff,
302 u64 start, u64 end, int failed_mirror,
303 submit_bio_hook_t *submit_bio_hook);
305 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
306 bool find_lock_delalloc_range(struct inode *inode,
307 struct page *locked_page, u64 *start,
310 struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
313 #ifdef CONFIG_BTRFS_DEBUG
314 void btrfs_extent_buffer_leak_debug_check(struct btrfs_fs_info *fs_info);
316 #define btrfs_extent_buffer_leak_debug_check(fs_info) do {} while (0)