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 "ulist.h" 11 12 /* 13 * flags for bio submission. The high bits indicate the compression 14 * type for this bio 15 */ 16 #define EXTENT_BIO_COMPRESSED 1 17 #define EXTENT_BIO_FLAG_SHIFT 16 18 19 enum { 20 EXTENT_BUFFER_UPTODATE, 21 EXTENT_BUFFER_DIRTY, 22 EXTENT_BUFFER_CORRUPT, 23 /* this got triggered by readahead */ 24 EXTENT_BUFFER_READAHEAD, 25 EXTENT_BUFFER_TREE_REF, 26 EXTENT_BUFFER_STALE, 27 EXTENT_BUFFER_WRITEBACK, 28 /* read IO error */ 29 EXTENT_BUFFER_READ_ERR, 30 EXTENT_BUFFER_UNMAPPED, 31 EXTENT_BUFFER_IN_TREE, 32 /* write IO error */ 33 EXTENT_BUFFER_WRITE_ERR, 34 }; 35 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) 44 45 /* 46 * page->private values. Every page that is controlled by the extent 47 * map has page->private set to one. 48 */ 49 #define EXTENT_PAGE_PRIVATE 1 50 51 /* 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. 57 */ 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))) 64 65 struct btrfs_root; 66 struct btrfs_inode; 67 struct btrfs_io_bio; 68 struct io_failure_record; 69 struct extent_io_tree; 70 71 typedef blk_status_t (submit_bio_hook_t)(struct inode *inode, struct bio *bio, 72 int mirror_num, 73 unsigned long bio_flags); 74 75 typedef blk_status_t (extent_submit_bio_start_t)(struct inode *inode, 76 struct bio *bio, u64 dio_file_offset); 77 78 #define INLINE_EXTENT_BUFFER_PAGES (BTRFS_MAX_METADATA_BLOCKSIZE / 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 /* >= 0 if eb belongs to a log tree, -1 otherwise */ 91 s8 log_index; 92 93 struct rw_semaphore lock; 94 95 struct page *pages[INLINE_EXTENT_BUFFER_PAGES]; 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 unsigned int 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 static inline void extent_set_compress_type(unsigned long *bio_flags, 147 int compress_type) 148 { 149 *bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT; 150 } 151 152 static inline int extent_compress_type(unsigned long bio_flags) 153 { 154 return bio_flags >> EXTENT_BIO_FLAG_SHIFT; 155 } 156 157 struct extent_map_tree; 158 159 typedef struct extent_map *(get_extent_t)(struct btrfs_inode *inode, 160 struct page *page, size_t pg_offset, 161 u64 start, u64 len); 162 163 int try_release_extent_mapping(struct page *page, gfp_t mask); 164 int try_release_extent_buffer(struct page *page); 165 166 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, 173 int mode); 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, 180 u64 start, u64 len); 181 void set_page_extent_mapped(struct page *page); 182 183 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, 188 u64 start); 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, 191 u64 start); 192 void free_extent_buffer(struct extent_buffer *eb); 193 void free_extent_buffer_stale(struct extent_buffer *eb); 194 #define WAIT_NONE 0 195 #define WAIT_COMPLETE 1 196 #define WAIT_PAGE_LOCK 2 197 int read_extent_buffer_pages(struct extent_buffer *eb, int wait, 198 int mirror_num); 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); 203 204 static inline int num_extent_pages(const struct extent_buffer *eb) 205 { 206 /* 207 * For sectorsize == PAGE_SIZE case, since nodesize is always aligned to 208 * sectorsize, it's just eb->len >> PAGE_SHIFT. 209 * 210 * For sectorsize < PAGE_SIZE case, we could have nodesize < PAGE_SIZE, 211 * thus have to ensure we get at least one page. 212 */ 213 return (eb->len >> PAGE_SHIFT) ?: 1; 214 } 215 216 static inline int extent_buffer_uptodate(const struct extent_buffer *eb) 217 { 218 return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); 219 } 220 221 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, 224 unsigned long start, 225 unsigned long len); 226 int read_extent_buffer_to_user_nofault(const struct extent_buffer *eb, 227 void __user *dst, unsigned long start, 228 unsigned long len); 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, 231 const void *src); 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, 239 unsigned long len); 240 void memcpy_extent_buffer(const struct extent_buffer *dst, 241 unsigned long dst_offset, unsigned long src_offset, 242 unsigned long len); 243 void memmove_extent_buffer(const struct extent_buffer *dst, 244 unsigned long dst_offset, unsigned long src_offset, 245 unsigned long len); 246 void memzero_extent_buffer(const struct extent_buffer *eb, unsigned long start, 247 unsigned long len); 248 int extent_buffer_test_bit(const struct extent_buffer *eb, unsigned long start, 249 unsigned long pos); 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, 254 unsigned long len); 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); 269 270 struct btrfs_fs_info; 271 struct btrfs_inode; 272 273 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); 278 279 /* 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. 286 */ 287 struct io_failure_record { 288 struct page *page; 289 u64 start; 290 u64 len; 291 u64 logical; 292 unsigned long bio_flags; 293 int this_mirror; 294 int failed_mirror; 295 int in_validation; 296 }; 297 298 299 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); 304 305 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 306 bool find_lock_delalloc_range(struct inode *inode, 307 struct page *locked_page, u64 *start, 308 u64 *end); 309 #endif 310 struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info, 311 u64 start); 312 313 #ifdef CONFIG_BTRFS_DEBUG 314 void btrfs_extent_buffer_leak_debug_check(struct btrfs_fs_info *fs_info); 315 #else 316 #define btrfs_extent_buffer_leak_debug_check(fs_info) do {} while (0) 317 #endif 318 319 #endif 320