1 /* SPDX-License-Identifier: GPL-2.0 */ 2 3 #ifndef BTRFS_EXTENT_IO_H 4 #define BTRFS_EXTENT_IO_H 5 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" 11 #include "ulist.h" 12 13 enum { 14 EXTENT_BUFFER_UPTODATE, 15 EXTENT_BUFFER_DIRTY, 16 EXTENT_BUFFER_CORRUPT, 17 /* this got triggered by readahead */ 18 EXTENT_BUFFER_READAHEAD, 19 EXTENT_BUFFER_TREE_REF, 20 EXTENT_BUFFER_STALE, 21 EXTENT_BUFFER_WRITEBACK, 22 /* read IO error */ 23 EXTENT_BUFFER_READ_ERR, 24 EXTENT_BUFFER_UNMAPPED, 25 EXTENT_BUFFER_IN_TREE, 26 /* write IO error */ 27 EXTENT_BUFFER_WRITE_ERR, 28 EXTENT_BUFFER_NO_CHECK, 29 }; 30 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) 39 40 /* 41 * page->private values. Every page that is controlled by the extent 42 * map has page->private set to one. 43 */ 44 #define EXTENT_PAGE_PRIVATE 1 45 46 /* 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. 52 */ 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))) 59 60 struct btrfs_bio; 61 struct btrfs_root; 62 struct btrfs_inode; 63 struct btrfs_io_bio; 64 struct btrfs_fs_info; 65 struct io_failure_record; 66 struct extent_io_tree; 67 68 typedef void (submit_bio_hook_t)(struct inode *inode, struct bio *bio, 69 int mirror_num, 70 enum btrfs_compression_type compress_type); 71 72 typedef blk_status_t (extent_submit_bio_start_t)(struct inode *inode, 73 struct bio *bio, u64 dio_file_offset); 74 75 #define INLINE_EXTENT_BUFFER_PAGES (BTRFS_MAX_METADATA_BLOCKSIZE / PAGE_SIZE) 76 struct extent_buffer { 77 u64 start; 78 unsigned long len; 79 unsigned long bflags; 80 struct btrfs_fs_info *fs_info; 81 spinlock_t refs_lock; 82 atomic_t refs; 83 atomic_t io_pages; 84 int read_mirror; 85 struct rcu_head rcu_head; 86 pid_t lock_owner; 87 /* >= 0 if eb belongs to a log tree, -1 otherwise */ 88 s8 log_index; 89 90 struct rw_semaphore lock; 91 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; 96 #endif 97 }; 98 99 /* 100 * Structure to record how many bytes and which ranges are set/cleared 101 */ 102 struct extent_changeset { 103 /* How many bytes are set/cleared in this operation */ 104 u64 bytes_changed; 105 106 /* Changed ranges */ 107 struct ulist range_changed; 108 }; 109 110 static inline void extent_changeset_init(struct extent_changeset *changeset) 111 { 112 changeset->bytes_changed = 0; 113 ulist_init(&changeset->range_changed); 114 } 115 116 static inline struct extent_changeset *extent_changeset_alloc(void) 117 { 118 struct extent_changeset *ret; 119 120 ret = kmalloc(sizeof(*ret), GFP_KERNEL); 121 if (!ret) 122 return NULL; 123 124 extent_changeset_init(ret); 125 return ret; 126 } 127 128 static inline void extent_changeset_release(struct extent_changeset *changeset) 129 { 130 if (!changeset) 131 return; 132 changeset->bytes_changed = 0; 133 ulist_release(&changeset->range_changed); 134 } 135 136 static inline void extent_changeset_free(struct extent_changeset *changeset) 137 { 138 if (!changeset) 139 return; 140 extent_changeset_release(changeset); 141 kfree(changeset); 142 } 143 144 struct extent_map_tree; 145 146 int try_release_extent_mapping(struct page *page, gfp_t mask); 147 int try_release_extent_buffer(struct page *page); 148 149 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, 157 u64 start, u64 len); 158 int set_page_extent_mapped(struct page *page); 159 void clear_page_extent_mapped(struct page *page); 160 161 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, 166 u64 start); 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, 169 u64 start); 170 void free_extent_buffer(struct extent_buffer *eb); 171 void free_extent_buffer_stale(struct extent_buffer *eb); 172 #define WAIT_NONE 0 173 #define WAIT_COMPLETE 1 174 #define WAIT_PAGE_LOCK 2 175 int read_extent_buffer_pages(struct extent_buffer *eb, int wait, 176 int mirror_num); 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); 181 182 static inline int num_extent_pages(const struct extent_buffer *eb) 183 { 184 /* 185 * For sectorsize == PAGE_SIZE case, since nodesize is always aligned to 186 * sectorsize, it's just eb->len >> PAGE_SHIFT. 187 * 188 * For sectorsize < PAGE_SIZE case, we could have nodesize < PAGE_SIZE, 189 * thus have to ensure we get at least one page. 190 */ 191 return (eb->len >> PAGE_SHIFT) ?: 1; 192 } 193 194 static inline int extent_buffer_uptodate(const struct extent_buffer *eb) 195 { 196 return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); 197 } 198 199 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, 202 unsigned long start, 203 unsigned long len); 204 int read_extent_buffer_to_user_nofault(const struct extent_buffer *eb, 205 void __user *dst, unsigned long start, 206 unsigned long len); 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, 209 const void *src); 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, 217 unsigned long len); 218 void memcpy_extent_buffer(const struct extent_buffer *dst, 219 unsigned long dst_offset, unsigned long src_offset, 220 unsigned long len); 221 void memmove_extent_buffer(const struct extent_buffer *dst, 222 unsigned long dst_offset, unsigned long src_offset, 223 unsigned long len); 224 void memzero_extent_buffer(const struct extent_buffer *eb, unsigned long start, 225 unsigned long len); 226 int extent_buffer_test_bit(const struct extent_buffer *eb, unsigned long start, 227 unsigned long pos); 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, 232 unsigned long len); 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); 243 244 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); 247 248 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); 250 251 /* 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. 258 */ 259 struct io_failure_record { 260 struct page *page; 261 u64 start; 262 u64 len; 263 u64 logical; 264 int this_mirror; 265 int failed_mirror; 266 int num_copies; 267 }; 268 269 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); 272 273 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 274 bool find_lock_delalloc_range(struct inode *inode, 275 struct page *locked_page, u64 *start, 276 u64 *end); 277 #endif 278 struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info, 279 u64 start); 280 281 #ifdef CONFIG_BTRFS_DEBUG 282 void btrfs_extent_buffer_leak_debug_check(struct btrfs_fs_info *fs_info); 283 #else 284 #define btrfs_extent_buffer_leak_debug_check(fs_info) do {} while (0) 285 #endif 286 287 #endif 288