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 "ulist.h" 10 11 /* 12 * flags for bio submission. The high bits indicate the compression 13 * type for this bio 14 */ 15 #define EXTENT_BIO_COMPRESSED 1 16 #define EXTENT_BIO_FLAG_SHIFT 16 17 18 enum { 19 EXTENT_BUFFER_UPTODATE, 20 EXTENT_BUFFER_DIRTY, 21 EXTENT_BUFFER_CORRUPT, 22 /* this got triggered by readahead */ 23 EXTENT_BUFFER_READAHEAD, 24 EXTENT_BUFFER_TREE_REF, 25 EXTENT_BUFFER_STALE, 26 EXTENT_BUFFER_WRITEBACK, 27 /* read IO error */ 28 EXTENT_BUFFER_READ_ERR, 29 EXTENT_BUFFER_UNMAPPED, 30 EXTENT_BUFFER_IN_TREE, 31 /* write IO error */ 32 EXTENT_BUFFER_WRITE_ERR, 33 }; 34 35 /* these are flags for __process_pages_contig */ 36 #define PAGE_UNLOCK (1 << 0) 37 #define PAGE_CLEAR_DIRTY (1 << 1) 38 #define PAGE_SET_WRITEBACK (1 << 2) 39 #define PAGE_END_WRITEBACK (1 << 3) 40 #define PAGE_SET_PRIVATE2 (1 << 4) 41 #define PAGE_SET_ERROR (1 << 5) 42 #define PAGE_LOCK (1 << 6) 43 44 /* 45 * page->private values. Every page that is controlled by the extent 46 * map has page->private set to one. 47 */ 48 #define EXTENT_PAGE_PRIVATE 1 49 50 /* 51 * The extent buffer bitmap operations are done with byte granularity instead of 52 * word granularity for two reasons: 53 * 1. The bitmaps must be little-endian on disk. 54 * 2. Bitmap items are not guaranteed to be aligned to a word and therefore a 55 * single word in a bitmap may straddle two pages in the extent buffer. 56 */ 57 #define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE) 58 #define BYTE_MASK ((1 << BITS_PER_BYTE) - 1) 59 #define BITMAP_FIRST_BYTE_MASK(start) \ 60 ((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK) 61 #define BITMAP_LAST_BYTE_MASK(nbits) \ 62 (BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1))) 63 64 struct btrfs_root; 65 struct btrfs_inode; 66 struct btrfs_io_bio; 67 struct io_failure_record; 68 struct extent_io_tree; 69 70 typedef blk_status_t (submit_bio_hook_t)(struct inode *inode, struct bio *bio, 71 int mirror_num, 72 unsigned long bio_flags); 73 74 typedef blk_status_t (extent_submit_bio_start_t)(void *private_data, 75 struct bio *bio, u64 bio_offset); 76 77 #define INLINE_EXTENT_BUFFER_PAGES 16 78 #define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_SIZE) 79 struct extent_buffer { 80 u64 start; 81 unsigned long len; 82 unsigned long bflags; 83 struct btrfs_fs_info *fs_info; 84 spinlock_t refs_lock; 85 atomic_t refs; 86 atomic_t io_pages; 87 int read_mirror; 88 struct rcu_head rcu_head; 89 pid_t lock_owner; 90 91 int blocking_writers; 92 atomic_t blocking_readers; 93 bool lock_recursed; 94 /* >= 0 if eb belongs to a log tree, -1 otherwise */ 95 short log_index; 96 97 /* protects write locks */ 98 rwlock_t lock; 99 100 /* readers use lock_wq while they wait for the write 101 * lock holders to unlock 102 */ 103 wait_queue_head_t write_lock_wq; 104 105 /* writers use read_lock_wq while they wait for readers 106 * to unlock 107 */ 108 wait_queue_head_t read_lock_wq; 109 struct page *pages[INLINE_EXTENT_BUFFER_PAGES]; 110 #ifdef CONFIG_BTRFS_DEBUG 111 int spinning_writers; 112 atomic_t spinning_readers; 113 atomic_t read_locks; 114 int write_locks; 115 struct list_head leak_list; 116 #endif 117 }; 118 119 /* 120 * Structure to record how many bytes and which ranges are set/cleared 121 */ 122 struct extent_changeset { 123 /* How many bytes are set/cleared in this operation */ 124 unsigned int bytes_changed; 125 126 /* Changed ranges */ 127 struct ulist range_changed; 128 }; 129 130 static inline void extent_changeset_init(struct extent_changeset *changeset) 131 { 132 changeset->bytes_changed = 0; 133 ulist_init(&changeset->range_changed); 134 } 135 136 static inline struct extent_changeset *extent_changeset_alloc(void) 137 { 138 struct extent_changeset *ret; 139 140 ret = kmalloc(sizeof(*ret), GFP_KERNEL); 141 if (!ret) 142 return NULL; 143 144 extent_changeset_init(ret); 145 return ret; 146 } 147 148 static inline void extent_changeset_release(struct extent_changeset *changeset) 149 { 150 if (!changeset) 151 return; 152 changeset->bytes_changed = 0; 153 ulist_release(&changeset->range_changed); 154 } 155 156 static inline void extent_changeset_free(struct extent_changeset *changeset) 157 { 158 if (!changeset) 159 return; 160 extent_changeset_release(changeset); 161 kfree(changeset); 162 } 163 164 static inline void extent_set_compress_type(unsigned long *bio_flags, 165 int compress_type) 166 { 167 *bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT; 168 } 169 170 static inline int extent_compress_type(unsigned long bio_flags) 171 { 172 return bio_flags >> EXTENT_BIO_FLAG_SHIFT; 173 } 174 175 struct extent_map_tree; 176 177 typedef struct extent_map *(get_extent_t)(struct btrfs_inode *inode, 178 struct page *page, size_t pg_offset, 179 u64 start, u64 len); 180 181 int try_release_extent_mapping(struct page *page, gfp_t mask); 182 int try_release_extent_buffer(struct page *page); 183 184 int __must_check submit_one_bio(struct bio *bio, int mirror_num, 185 unsigned long bio_flags); 186 int btrfs_do_readpage(struct page *page, struct extent_map **em_cached, 187 struct bio **bio, unsigned long *bio_flags, 188 unsigned int read_flags, u64 *prev_em_start); 189 int extent_write_full_page(struct page *page, struct writeback_control *wbc); 190 int extent_write_locked_range(struct inode *inode, u64 start, u64 end, 191 int mode); 192 int extent_writepages(struct address_space *mapping, 193 struct writeback_control *wbc); 194 int btree_write_cache_pages(struct address_space *mapping, 195 struct writeback_control *wbc); 196 void extent_readahead(struct readahead_control *rac); 197 int extent_fiemap(struct btrfs_inode *inode, struct fiemap_extent_info *fieinfo, 198 u64 start, u64 len); 199 void set_page_extent_mapped(struct page *page); 200 201 struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info, 202 u64 start); 203 struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info, 204 u64 start, unsigned long len); 205 struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info, 206 u64 start); 207 struct extent_buffer *btrfs_clone_extent_buffer(const struct extent_buffer *src); 208 struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info, 209 u64 start); 210 void free_extent_buffer(struct extent_buffer *eb); 211 void free_extent_buffer_stale(struct extent_buffer *eb); 212 #define WAIT_NONE 0 213 #define WAIT_COMPLETE 1 214 #define WAIT_PAGE_LOCK 2 215 int read_extent_buffer_pages(struct extent_buffer *eb, int wait, 216 int mirror_num); 217 void wait_on_extent_buffer_writeback(struct extent_buffer *eb); 218 219 static inline int num_extent_pages(const struct extent_buffer *eb) 220 { 221 return (round_up(eb->start + eb->len, PAGE_SIZE) >> PAGE_SHIFT) - 222 (eb->start >> PAGE_SHIFT); 223 } 224 225 static inline int extent_buffer_uptodate(const struct extent_buffer *eb) 226 { 227 return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); 228 } 229 230 int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv, 231 unsigned long start, unsigned long len); 232 void read_extent_buffer(const struct extent_buffer *eb, void *dst, 233 unsigned long start, 234 unsigned long len); 235 int read_extent_buffer_to_user_nofault(const struct extent_buffer *eb, 236 void __user *dst, unsigned long start, 237 unsigned long len); 238 void write_extent_buffer_fsid(const struct extent_buffer *eb, const void *src); 239 void write_extent_buffer_chunk_tree_uuid(const struct extent_buffer *eb, 240 const void *src); 241 void write_extent_buffer(const struct extent_buffer *eb, const void *src, 242 unsigned long start, unsigned long len); 243 void copy_extent_buffer_full(const struct extent_buffer *dst, 244 const struct extent_buffer *src); 245 void copy_extent_buffer(const struct extent_buffer *dst, 246 const struct extent_buffer *src, 247 unsigned long dst_offset, unsigned long src_offset, 248 unsigned long len); 249 void memcpy_extent_buffer(const struct extent_buffer *dst, 250 unsigned long dst_offset, unsigned long src_offset, 251 unsigned long len); 252 void memmove_extent_buffer(const struct extent_buffer *dst, 253 unsigned long dst_offset, unsigned long src_offset, 254 unsigned long len); 255 void memzero_extent_buffer(const struct extent_buffer *eb, unsigned long start, 256 unsigned long len); 257 int extent_buffer_test_bit(const struct extent_buffer *eb, unsigned long start, 258 unsigned long pos); 259 void extent_buffer_bitmap_set(const struct extent_buffer *eb, unsigned long start, 260 unsigned long pos, unsigned long len); 261 void extent_buffer_bitmap_clear(const struct extent_buffer *eb, 262 unsigned long start, unsigned long pos, 263 unsigned long len); 264 void clear_extent_buffer_dirty(const struct extent_buffer *eb); 265 bool set_extent_buffer_dirty(struct extent_buffer *eb); 266 void set_extent_buffer_uptodate(struct extent_buffer *eb); 267 void clear_extent_buffer_uptodate(struct extent_buffer *eb); 268 int extent_buffer_under_io(const struct extent_buffer *eb); 269 void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end); 270 void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end); 271 void extent_clear_unlock_delalloc(struct btrfs_inode *inode, u64 start, u64 end, 272 struct page *locked_page, 273 unsigned bits_to_clear, 274 unsigned long page_ops); 275 struct bio *btrfs_bio_alloc(u64 first_byte); 276 struct bio *btrfs_io_bio_alloc(unsigned int nr_iovecs); 277 struct bio *btrfs_bio_clone(struct bio *bio); 278 struct bio *btrfs_bio_clone_partial(struct bio *orig, int offset, int size); 279 280 struct btrfs_fs_info; 281 struct btrfs_inode; 282 283 int repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start, 284 u64 length, u64 logical, struct page *page, 285 unsigned int pg_offset, int mirror_num); 286 void end_extent_writepage(struct page *page, int err, u64 start, u64 end); 287 int btrfs_repair_eb_io_failure(const struct extent_buffer *eb, int mirror_num); 288 289 /* 290 * When IO fails, either with EIO or csum verification fails, we 291 * try other mirrors that might have a good copy of the data. This 292 * io_failure_record is used to record state as we go through all the 293 * mirrors. If another mirror has good data, the page is set up to date 294 * and things continue. If a good mirror can't be found, the original 295 * bio end_io callback is called to indicate things have failed. 296 */ 297 struct io_failure_record { 298 struct page *page; 299 u64 start; 300 u64 len; 301 u64 logical; 302 unsigned long bio_flags; 303 int this_mirror; 304 int failed_mirror; 305 int in_validation; 306 }; 307 308 309 blk_status_t btrfs_submit_read_repair(struct inode *inode, 310 struct bio *failed_bio, u64 phy_offset, 311 struct page *page, unsigned int pgoff, 312 u64 start, u64 end, int failed_mirror, 313 submit_bio_hook_t *submit_bio_hook); 314 315 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 316 bool find_lock_delalloc_range(struct inode *inode, 317 struct page *locked_page, u64 *start, 318 u64 *end); 319 #endif 320 struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info, 321 u64 start); 322 323 #ifdef CONFIG_BTRFS_DEBUG 324 void btrfs_extent_buffer_leak_debug_check(struct btrfs_fs_info *fs_info); 325 #else 326 #define btrfs_extent_buffer_leak_debug_check(fs_info) do {} while (0) 327 #endif 328 329 #endif 330