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>
10 #include "compression.h"
14 EXTENT_BUFFER_UPTODATE,
16 EXTENT_BUFFER_CORRUPT,
17 /* this got triggered by readahead */
18 EXTENT_BUFFER_READAHEAD,
19 EXTENT_BUFFER_TREE_REF,
21 EXTENT_BUFFER_WRITEBACK,
23 EXTENT_BUFFER_READ_ERR,
24 EXTENT_BUFFER_UNMAPPED,
25 EXTENT_BUFFER_IN_TREE,
27 EXTENT_BUFFER_WRITE_ERR,
28 EXTENT_BUFFER_NO_CHECK,
31 /* these are flags for __process_pages_contig */
32 #define PAGE_UNLOCK (1 << 0)
33 /* Page starts writeback, clear dirty bit and set writeback bit */
34 #define PAGE_START_WRITEBACK (1 << 1)
35 #define PAGE_END_WRITEBACK (1 << 2)
36 #define PAGE_SET_ORDERED (1 << 3)
37 #define PAGE_SET_ERROR (1 << 4)
38 #define PAGE_LOCK (1 << 5)
41 * page->private values. Every page that is controlled by the extent
42 * map has page->private set to one.
44 #define EXTENT_PAGE_PRIVATE 1
47 * The extent buffer bitmap operations are done with byte granularity instead of
48 * word granularity for two reasons:
49 * 1. The bitmaps must be little-endian on disk.
50 * 2. Bitmap items are not guaranteed to be aligned to a word and therefore a
51 * single word in a bitmap may straddle two pages in the extent buffer.
53 #define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE)
54 #define BYTE_MASK ((1 << BITS_PER_BYTE) - 1)
55 #define BITMAP_FIRST_BYTE_MASK(start) \
56 ((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK)
57 #define BITMAP_LAST_BYTE_MASK(nbits) \
58 (BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1)))
65 struct io_failure_record;
66 struct extent_io_tree;
68 typedef void (submit_bio_hook_t)(struct inode *inode, struct bio *bio,
70 enum btrfs_compression_type compress_type);
72 typedef blk_status_t (extent_submit_bio_start_t)(struct inode *inode,
73 struct bio *bio, u64 dio_file_offset);
75 #define INLINE_EXTENT_BUFFER_PAGES (BTRFS_MAX_METADATA_BLOCKSIZE / PAGE_SIZE)
76 struct extent_buffer {
80 struct btrfs_fs_info *fs_info;
85 struct rcu_head rcu_head;
87 /* >= 0 if eb belongs to a log tree, -1 otherwise */
90 struct rw_semaphore lock;
92 struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
93 struct list_head release_list;
94 #ifdef CONFIG_BTRFS_DEBUG
95 struct list_head leak_list;
100 * Structure to record how many bytes and which ranges are set/cleared
102 struct extent_changeset {
103 /* How many bytes are set/cleared in this operation */
107 struct ulist range_changed;
110 static inline void extent_changeset_init(struct extent_changeset *changeset)
112 changeset->bytes_changed = 0;
113 ulist_init(&changeset->range_changed);
116 static inline struct extent_changeset *extent_changeset_alloc(void)
118 struct extent_changeset *ret;
120 ret = kmalloc(sizeof(*ret), GFP_KERNEL);
124 extent_changeset_init(ret);
128 static inline void extent_changeset_release(struct extent_changeset *changeset)
132 changeset->bytes_changed = 0;
133 ulist_release(&changeset->range_changed);
136 static inline void extent_changeset_free(struct extent_changeset *changeset)
140 extent_changeset_release(changeset);
144 struct extent_map_tree;
146 int try_release_extent_mapping(struct page *page, gfp_t mask);
147 int try_release_extent_buffer(struct page *page);
149 int btrfs_read_folio(struct file *file, struct folio *folio);
150 int extent_write_locked_range(struct inode *inode, u64 start, u64 end);
151 int extent_writepages(struct address_space *mapping,
152 struct writeback_control *wbc);
153 int btree_write_cache_pages(struct address_space *mapping,
154 struct writeback_control *wbc);
155 void extent_readahead(struct readahead_control *rac);
156 int extent_fiemap(struct btrfs_inode *inode, struct fiemap_extent_info *fieinfo,
158 int set_page_extent_mapped(struct page *page);
159 void clear_page_extent_mapped(struct page *page);
161 struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
162 u64 start, u64 owner_root, int level);
163 struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
164 u64 start, unsigned long len);
165 struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
167 struct extent_buffer *btrfs_clone_extent_buffer(const struct extent_buffer *src);
168 struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
170 void free_extent_buffer(struct extent_buffer *eb);
171 void free_extent_buffer_stale(struct extent_buffer *eb);
173 #define WAIT_COMPLETE 1
174 #define WAIT_PAGE_LOCK 2
175 int read_extent_buffer_pages(struct extent_buffer *eb, int wait,
177 void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
178 void btrfs_readahead_tree_block(struct btrfs_fs_info *fs_info,
179 u64 bytenr, u64 owner_root, u64 gen, int level);
180 void btrfs_readahead_node_child(struct extent_buffer *node, int slot);
182 static inline int num_extent_pages(const struct extent_buffer *eb)
185 * For sectorsize == PAGE_SIZE case, since nodesize is always aligned to
186 * sectorsize, it's just eb->len >> PAGE_SHIFT.
188 * For sectorsize < PAGE_SIZE case, we could have nodesize < PAGE_SIZE,
189 * thus have to ensure we get at least one page.
191 return (eb->len >> PAGE_SHIFT) ?: 1;
194 static inline int extent_buffer_uptodate(const struct extent_buffer *eb)
196 return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
199 int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv,
200 unsigned long start, unsigned long len);
201 void read_extent_buffer(const struct extent_buffer *eb, void *dst,
204 int read_extent_buffer_to_user_nofault(const struct extent_buffer *eb,
205 void __user *dst, unsigned long start,
207 void write_extent_buffer_fsid(const struct extent_buffer *eb, const void *src);
208 void write_extent_buffer_chunk_tree_uuid(const struct extent_buffer *eb,
210 void write_extent_buffer(const struct extent_buffer *eb, const void *src,
211 unsigned long start, unsigned long len);
212 void copy_extent_buffer_full(const struct extent_buffer *dst,
213 const struct extent_buffer *src);
214 void copy_extent_buffer(const struct extent_buffer *dst,
215 const struct extent_buffer *src,
216 unsigned long dst_offset, unsigned long src_offset,
218 void memcpy_extent_buffer(const struct extent_buffer *dst,
219 unsigned long dst_offset, unsigned long src_offset,
221 void memmove_extent_buffer(const struct extent_buffer *dst,
222 unsigned long dst_offset, unsigned long src_offset,
224 void memzero_extent_buffer(const struct extent_buffer *eb, unsigned long start,
226 int extent_buffer_test_bit(const struct extent_buffer *eb, unsigned long start,
228 void extent_buffer_bitmap_set(const struct extent_buffer *eb, unsigned long start,
229 unsigned long pos, unsigned long len);
230 void extent_buffer_bitmap_clear(const struct extent_buffer *eb,
231 unsigned long start, unsigned long pos,
233 void clear_extent_buffer_dirty(const struct extent_buffer *eb);
234 bool set_extent_buffer_dirty(struct extent_buffer *eb);
235 void set_extent_buffer_uptodate(struct extent_buffer *eb);
236 void clear_extent_buffer_uptodate(struct extent_buffer *eb);
237 int extent_buffer_under_io(const struct extent_buffer *eb);
238 void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
239 void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
240 void extent_clear_unlock_delalloc(struct btrfs_inode *inode, u64 start, u64 end,
241 struct page *locked_page,
242 u32 bits_to_clear, unsigned long page_ops);
244 int btrfs_alloc_page_array(unsigned int nr_pages, struct page **page_array);
245 struct bio *btrfs_bio_alloc(unsigned int nr_iovecs);
246 struct bio *btrfs_bio_clone_partial(struct bio *orig, u64 offset, u64 size);
248 void end_extent_writepage(struct page *page, int err, u64 start, u64 end);
249 int btrfs_repair_eb_io_failure(const struct extent_buffer *eb, int mirror_num);
252 * When IO fails, either with EIO or csum verification fails, we
253 * try other mirrors that might have a good copy of the data. This
254 * io_failure_record is used to record state as we go through all the
255 * mirrors. If another mirror has good data, the sector is set up to date
256 * and things continue. If a good mirror can't be found, the original
257 * bio end_io callback is called to indicate things have failed.
259 struct io_failure_record {
269 int btrfs_repair_one_sector(struct inode *inode, struct btrfs_bio *failed_bbio,
270 u32 bio_offset, struct page *page, unsigned int pgoff,
271 submit_bio_hook_t *submit_bio_hook);
273 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
274 bool find_lock_delalloc_range(struct inode *inode,
275 struct page *locked_page, u64 *start,
278 struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
281 #ifdef CONFIG_BTRFS_DEBUG
282 void btrfs_extent_buffer_leak_debug_check(struct btrfs_fs_info *fs_info);
284 #define btrfs_extent_buffer_leak_debug_check(fs_info) do {} while (0)