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_fs_info; 64 struct io_failure_record; 65 struct extent_io_tree; 66 67 int __init extent_buffer_init_cachep(void); 68 void __cold extent_buffer_free_cachep(void); 69 70 typedef void (submit_bio_hook_t)(struct inode *inode, struct bio *bio, 71 int mirror_num, 72 enum btrfs_compression_type compress_type); 73 74 typedef blk_status_t (extent_submit_bio_start_t)(struct inode *inode, 75 struct bio *bio, u64 dio_file_offset); 76 77 #define INLINE_EXTENT_BUFFER_PAGES (BTRFS_MAX_METADATA_BLOCKSIZE / PAGE_SIZE) 78 struct extent_buffer { 79 u64 start; 80 unsigned long len; 81 unsigned long bflags; 82 struct btrfs_fs_info *fs_info; 83 spinlock_t refs_lock; 84 atomic_t refs; 85 atomic_t io_pages; 86 int read_mirror; 87 struct rcu_head rcu_head; 88 pid_t lock_owner; 89 /* >= 0 if eb belongs to a log tree, -1 otherwise */ 90 s8 log_index; 91 92 struct rw_semaphore lock; 93 94 struct page *pages[INLINE_EXTENT_BUFFER_PAGES]; 95 struct list_head release_list; 96 #ifdef CONFIG_BTRFS_DEBUG 97 struct list_head leak_list; 98 #endif 99 }; 100 101 /* 102 * Structure to record how many bytes and which ranges are set/cleared 103 */ 104 struct extent_changeset { 105 /* How many bytes are set/cleared in this operation */ 106 u64 bytes_changed; 107 108 /* Changed ranges */ 109 struct ulist range_changed; 110 }; 111 112 static inline void extent_changeset_init(struct extent_changeset *changeset) 113 { 114 changeset->bytes_changed = 0; 115 ulist_init(&changeset->range_changed); 116 } 117 118 static inline struct extent_changeset *extent_changeset_alloc(void) 119 { 120 struct extent_changeset *ret; 121 122 ret = kmalloc(sizeof(*ret), GFP_KERNEL); 123 if (!ret) 124 return NULL; 125 126 extent_changeset_init(ret); 127 return ret; 128 } 129 130 static inline void extent_changeset_release(struct extent_changeset *changeset) 131 { 132 if (!changeset) 133 return; 134 changeset->bytes_changed = 0; 135 ulist_release(&changeset->range_changed); 136 } 137 138 static inline void extent_changeset_free(struct extent_changeset *changeset) 139 { 140 if (!changeset) 141 return; 142 extent_changeset_release(changeset); 143 kfree(changeset); 144 } 145 146 struct extent_map_tree; 147 148 int try_release_extent_mapping(struct page *page, gfp_t mask); 149 int try_release_extent_buffer(struct page *page); 150 151 int btrfs_read_folio(struct file *file, struct folio *folio); 152 int extent_write_locked_range(struct inode *inode, u64 start, u64 end); 153 int extent_writepages(struct address_space *mapping, 154 struct writeback_control *wbc); 155 int btree_write_cache_pages(struct address_space *mapping, 156 struct writeback_control *wbc); 157 void extent_readahead(struct readahead_control *rac); 158 int extent_fiemap(struct btrfs_inode *inode, struct fiemap_extent_info *fieinfo, 159 u64 start, u64 len); 160 int set_page_extent_mapped(struct page *page); 161 void clear_page_extent_mapped(struct page *page); 162 163 struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info, 164 u64 start, u64 owner_root, int level); 165 struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info, 166 u64 start, unsigned long len); 167 struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info, 168 u64 start); 169 struct extent_buffer *btrfs_clone_extent_buffer(const struct extent_buffer *src); 170 struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info, 171 u64 start); 172 void free_extent_buffer(struct extent_buffer *eb); 173 void free_extent_buffer_stale(struct extent_buffer *eb); 174 #define WAIT_NONE 0 175 #define WAIT_COMPLETE 1 176 #define WAIT_PAGE_LOCK 2 177 int read_extent_buffer_pages(struct extent_buffer *eb, int wait, 178 int mirror_num); 179 void wait_on_extent_buffer_writeback(struct extent_buffer *eb); 180 void btrfs_readahead_tree_block(struct btrfs_fs_info *fs_info, 181 u64 bytenr, u64 owner_root, u64 gen, int level); 182 void btrfs_readahead_node_child(struct extent_buffer *node, int slot); 183 184 static inline int num_extent_pages(const struct extent_buffer *eb) 185 { 186 /* 187 * For sectorsize == PAGE_SIZE case, since nodesize is always aligned to 188 * sectorsize, it's just eb->len >> PAGE_SHIFT. 189 * 190 * For sectorsize < PAGE_SIZE case, we could have nodesize < PAGE_SIZE, 191 * thus have to ensure we get at least one page. 192 */ 193 return (eb->len >> PAGE_SHIFT) ?: 1; 194 } 195 196 static inline int extent_buffer_uptodate(const struct extent_buffer *eb) 197 { 198 return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); 199 } 200 201 int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv, 202 unsigned long start, unsigned long len); 203 void read_extent_buffer(const struct extent_buffer *eb, void *dst, 204 unsigned long start, 205 unsigned long len); 206 int read_extent_buffer_to_user_nofault(const struct extent_buffer *eb, 207 void __user *dst, unsigned long start, 208 unsigned long len); 209 void write_extent_buffer_fsid(const struct extent_buffer *eb, const void *src); 210 void write_extent_buffer_chunk_tree_uuid(const struct extent_buffer *eb, 211 const void *src); 212 void write_extent_buffer(const struct extent_buffer *eb, const void *src, 213 unsigned long start, unsigned long len); 214 void copy_extent_buffer_full(const struct extent_buffer *dst, 215 const struct extent_buffer *src); 216 void copy_extent_buffer(const struct extent_buffer *dst, 217 const struct extent_buffer *src, 218 unsigned long dst_offset, unsigned long src_offset, 219 unsigned long len); 220 void memcpy_extent_buffer(const struct extent_buffer *dst, 221 unsigned long dst_offset, unsigned long src_offset, 222 unsigned long len); 223 void memmove_extent_buffer(const struct extent_buffer *dst, 224 unsigned long dst_offset, unsigned long src_offset, 225 unsigned long len); 226 void memzero_extent_buffer(const struct extent_buffer *eb, unsigned long start, 227 unsigned long len); 228 int extent_buffer_test_bit(const struct extent_buffer *eb, unsigned long start, 229 unsigned long pos); 230 void extent_buffer_bitmap_set(const struct extent_buffer *eb, unsigned long start, 231 unsigned long pos, unsigned long len); 232 void extent_buffer_bitmap_clear(const struct extent_buffer *eb, 233 unsigned long start, unsigned long pos, 234 unsigned long len); 235 void clear_extent_buffer_dirty(const struct extent_buffer *eb); 236 bool set_extent_buffer_dirty(struct extent_buffer *eb); 237 void set_extent_buffer_uptodate(struct extent_buffer *eb); 238 void clear_extent_buffer_uptodate(struct extent_buffer *eb); 239 int extent_buffer_under_io(const struct extent_buffer *eb); 240 void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end); 241 void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end); 242 void extent_clear_unlock_delalloc(struct btrfs_inode *inode, u64 start, u64 end, 243 struct page *locked_page, 244 u32 bits_to_clear, unsigned long page_ops); 245 int extent_invalidate_folio(struct extent_io_tree *tree, 246 struct folio *folio, size_t offset); 247 248 int btrfs_alloc_page_array(unsigned int nr_pages, struct page **page_array); 249 250 void end_extent_writepage(struct page *page, int err, u64 start, u64 end); 251 int btrfs_repair_eb_io_failure(const struct extent_buffer *eb, int mirror_num); 252 253 /* 254 * When IO fails, either with EIO or csum verification fails, we 255 * try other mirrors that might have a good copy of the data. This 256 * io_failure_record is used to record state as we go through all the 257 * mirrors. If another mirror has good data, the sector is set up to date 258 * and things continue. If a good mirror can't be found, the original 259 * bio end_io callback is called to indicate things have failed. 260 */ 261 struct io_failure_record { 262 /* Use rb_simple_node for search/insert */ 263 struct { 264 struct rb_node rb_node; 265 u64 bytenr; 266 }; 267 struct page *page; 268 u64 len; 269 u64 logical; 270 int this_mirror; 271 int failed_mirror; 272 int num_copies; 273 }; 274 275 int btrfs_repair_one_sector(struct inode *inode, struct btrfs_bio *failed_bbio, 276 u32 bio_offset, struct page *page, unsigned int pgoff, 277 submit_bio_hook_t *submit_bio_hook); 278 void btrfs_free_io_failure_record(struct btrfs_inode *inode, u64 start, u64 end); 279 int btrfs_clean_io_failure(struct btrfs_inode *inode, u64 start, 280 struct page *page, unsigned int pg_offset); 281 282 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 283 bool find_lock_delalloc_range(struct inode *inode, 284 struct page *locked_page, u64 *start, 285 u64 *end); 286 #endif 287 struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info, 288 u64 start); 289 290 #ifdef CONFIG_BTRFS_DEBUG 291 void btrfs_extent_buffer_leak_debug_check(struct btrfs_fs_info *fs_info); 292 #else 293 #define btrfs_extent_buffer_leak_debug_check(fs_info) do {} while (0) 294 #endif 295 296 #endif 297