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1/* SPDX-License-Identifier: GPL-2.0 */2 3#ifndef BTRFS_EXTENT_IO_H4#define BTRFS_EXTENT_IO_H5 6#include <linux/rbtree.h>7#include <linux/refcount.h>8#include <linux/fiemap.h>9#include <linux/btrfs_tree.h>10#include <linux/spinlock.h>11#include <linux/atomic.h>12#include <linux/rwsem.h>13#include <linux/list.h>14#include <linux/slab.h>15#include "compression.h"16#include "messages.h"17#include "ulist.h"18#include "misc.h"19 20struct page;21struct file;22struct folio;23struct inode;24struct fiemap_extent_info;25struct readahead_control;26struct address_space;27struct writeback_control;28struct extent_io_tree;29struct extent_map_tree;30struct extent_state;31struct btrfs_block_group;32struct btrfs_fs_info;33struct btrfs_inode;34struct btrfs_root;35struct btrfs_trans_handle;36struct btrfs_tree_parent_check;37 38enum {39 EXTENT_BUFFER_UPTODATE,40 EXTENT_BUFFER_DIRTY,41 EXTENT_BUFFER_CORRUPT,42 /* this got triggered by readahead */43 EXTENT_BUFFER_READAHEAD,44 EXTENT_BUFFER_TREE_REF,45 EXTENT_BUFFER_STALE,46 EXTENT_BUFFER_WRITEBACK,47 /* read IO error */48 EXTENT_BUFFER_READ_ERR,49 EXTENT_BUFFER_UNMAPPED,50 EXTENT_BUFFER_IN_TREE,51 /* write IO error */52 EXTENT_BUFFER_WRITE_ERR,53 /* Indicate the extent buffer is written zeroed out (for zoned) */54 EXTENT_BUFFER_ZONED_ZEROOUT,55 /* Indicate that extent buffer pages a being read */56 EXTENT_BUFFER_READING,57};58 59/* these are flags for __process_pages_contig */60enum {61 ENUM_BIT(PAGE_UNLOCK),62 /* Page starts writeback, clear dirty bit and set writeback bit */63 ENUM_BIT(PAGE_START_WRITEBACK),64 ENUM_BIT(PAGE_END_WRITEBACK),65 ENUM_BIT(PAGE_SET_ORDERED),66};67 68/*69 * Folio private values. Every page that is controlled by the extent map has70 * folio private set to this value.71 */72#define EXTENT_FOLIO_PRIVATE 173 74/*75 * The extent buffer bitmap operations are done with byte granularity instead of76 * word granularity for two reasons:77 * 1. The bitmaps must be little-endian on disk.78 * 2. Bitmap items are not guaranteed to be aligned to a word and therefore a79 * single word in a bitmap may straddle two pages in the extent buffer.80 */81#define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE)82#define BYTE_MASK ((1 << BITS_PER_BYTE) - 1)83#define BITMAP_FIRST_BYTE_MASK(start) \84 ((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK)85#define BITMAP_LAST_BYTE_MASK(nbits) \86 (BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1)))87 88 89int __init extent_buffer_init_cachep(void);90void __cold extent_buffer_free_cachep(void);91 92#define INLINE_EXTENT_BUFFER_PAGES (BTRFS_MAX_METADATA_BLOCKSIZE / PAGE_SIZE)93struct extent_buffer {94 u64 start;95 u32 len;96 u32 folio_size;97 unsigned long bflags;98 struct btrfs_fs_info *fs_info;99 100 /*101 * The address where the eb can be accessed without any cross-page handling.102 * This can be NULL if not possible.103 */104 void *addr;105 106 spinlock_t refs_lock;107 atomic_t refs;108 int read_mirror;109 /* >= 0 if eb belongs to a log tree, -1 otherwise */110 s8 log_index;111 u8 folio_shift;112 struct rcu_head rcu_head;113 114 struct rw_semaphore lock;115 116 /*117 * Pointers to all the folios of the extent buffer.118 *119 * For now the folio is always order 0 (aka, a single page).120 */121 struct folio *folios[INLINE_EXTENT_BUFFER_PAGES];122#ifdef CONFIG_BTRFS_DEBUG123 struct list_head leak_list;124 pid_t lock_owner;125#endif126};127 128struct btrfs_eb_write_context {129 struct writeback_control *wbc;130 struct extent_buffer *eb;131 /* Block group @eb resides in. Only used for zoned mode. */132 struct btrfs_block_group *zoned_bg;133};134 135static inline unsigned long offset_in_eb_folio(const struct extent_buffer *eb,136 u64 start)137{138 ASSERT(eb->folio_size);139 return start & (eb->folio_size - 1);140}141 142/*143 * Get the correct offset inside the page of extent buffer.144 *145 * @eb: target extent buffer146 * @start: offset inside the extent buffer147 *148 * Will handle both sectorsize == PAGE_SIZE and sectorsize < PAGE_SIZE cases.149 */150static inline size_t get_eb_offset_in_folio(const struct extent_buffer *eb,151 unsigned long offset)152{153 /*154 * 1) sectorsize == PAGE_SIZE and nodesize >= PAGE_SIZE case155 * 1.1) One large folio covering the whole eb156 * The eb->start is aligned to folio size, thus adding it157 * won't cause any difference.158 * 1.2) Several page sized folios159 * The eb->start is aligned to folio (page) size, thus160 * adding it won't cause any difference.161 *162 * 2) sectorsize < PAGE_SIZE and nodesize < PAGE_SIZE case163 * In this case there would only be one page sized folio, and there164 * may be several different extent buffers in the page/folio.165 * We need to add eb->start to properly access the offset inside166 * that eb.167 */168 return offset_in_folio(eb->folios[0], offset + eb->start);169}170 171static inline unsigned long get_eb_folio_index(const struct extent_buffer *eb,172 unsigned long offset)173{174 /*175 * 1) sectorsize == PAGE_SIZE and nodesize >= PAGE_SIZE case176 * 1.1) One large folio covering the whole eb.177 * the folio_shift would be large enough to always make us178 * return 0 as index.179 * 1.2) Several page sized folios180 * The folio_shift would be PAGE_SHIFT, giving us the correct181 * index.182 *183 * 2) sectorsize < PAGE_SIZE and nodesize < PAGE_SIZE case184 * The folio would only be page sized, and always give us 0 as index.185 */186 return offset >> eb->folio_shift;187}188 189/*190 * Structure to record how many bytes and which ranges are set/cleared191 */192struct extent_changeset {193 /* How many bytes are set/cleared in this operation */194 u64 bytes_changed;195 196 /* Changed ranges */197 struct ulist range_changed;198};199 200static inline void extent_changeset_init(struct extent_changeset *changeset)201{202 changeset->bytes_changed = 0;203 ulist_init(&changeset->range_changed);204}205 206static inline struct extent_changeset *extent_changeset_alloc(void)207{208 struct extent_changeset *ret;209 210 ret = kmalloc(sizeof(*ret), GFP_KERNEL);211 if (!ret)212 return NULL;213 214 extent_changeset_init(ret);215 return ret;216}217 218static inline void extent_changeset_prealloc(struct extent_changeset *changeset, gfp_t gfp_mask)219{220 ulist_prealloc(&changeset->range_changed, gfp_mask);221}222 223static inline void extent_changeset_release(struct extent_changeset *changeset)224{225 if (!changeset)226 return;227 changeset->bytes_changed = 0;228 ulist_release(&changeset->range_changed);229}230 231static inline void extent_changeset_free(struct extent_changeset *changeset)232{233 if (!changeset)234 return;235 extent_changeset_release(changeset);236 kfree(changeset);237}238 239bool try_release_extent_mapping(struct folio *folio, gfp_t mask);240int try_release_extent_buffer(struct folio *folio);241 242int btrfs_read_folio(struct file *file, struct folio *folio);243void extent_write_locked_range(struct inode *inode, const struct folio *locked_folio,244 u64 start, u64 end, struct writeback_control *wbc,245 bool pages_dirty);246int btrfs_writepages(struct address_space *mapping, struct writeback_control *wbc);247int btree_write_cache_pages(struct address_space *mapping,248 struct writeback_control *wbc);249void btrfs_readahead(struct readahead_control *rac);250int set_folio_extent_mapped(struct folio *folio);251int set_page_extent_mapped(struct page *page);252void clear_folio_extent_mapped(struct folio *folio);253 254struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,255 u64 start, u64 owner_root, int level);256struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,257 u64 start, unsigned long len);258struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,259 u64 start);260struct extent_buffer *btrfs_clone_extent_buffer(const struct extent_buffer *src);261struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,262 u64 start);263void free_extent_buffer(struct extent_buffer *eb);264void free_extent_buffer_stale(struct extent_buffer *eb);265#define WAIT_NONE 0266#define WAIT_COMPLETE 1267#define WAIT_PAGE_LOCK 2268int read_extent_buffer_pages(struct extent_buffer *eb, int wait, int mirror_num,269 const struct btrfs_tree_parent_check *parent_check);270void wait_on_extent_buffer_writeback(struct extent_buffer *eb);271void btrfs_readahead_tree_block(struct btrfs_fs_info *fs_info,272 u64 bytenr, u64 owner_root, u64 gen, int level);273void btrfs_readahead_node_child(struct extent_buffer *node, int slot);274 275static inline int num_extent_pages(const struct extent_buffer *eb)276{277 /*278 * For sectorsize == PAGE_SIZE case, since nodesize is always aligned to279 * sectorsize, it's just eb->len >> PAGE_SHIFT.280 *281 * For sectorsize < PAGE_SIZE case, we could have nodesize < PAGE_SIZE,282 * thus have to ensure we get at least one page.283 */284 return (eb->len >> PAGE_SHIFT) ?: 1;285}286 287/*288 * This can only be determined at runtime by checking eb::folios[0].289 *290 * As we can have either one large folio covering the whole eb291 * (either nodesize <= PAGE_SIZE, or high order folio), or multiple292 * single-paged folios.293 */294static inline int num_extent_folios(const struct extent_buffer *eb)295{296 if (folio_order(eb->folios[0]))297 return 1;298 return num_extent_pages(eb);299}300 301static inline int extent_buffer_uptodate(const struct extent_buffer *eb)302{303 return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);304}305 306int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv,307 unsigned long start, unsigned long len);308void read_extent_buffer(const struct extent_buffer *eb, void *dst,309 unsigned long start,310 unsigned long len);311int read_extent_buffer_to_user_nofault(const struct extent_buffer *eb,312 void __user *dst, unsigned long start,313 unsigned long len);314void write_extent_buffer(const struct extent_buffer *eb, const void *src,315 unsigned long start, unsigned long len);316 317static inline void write_extent_buffer_chunk_tree_uuid(318 const struct extent_buffer *eb, const void *chunk_tree_uuid)319{320 write_extent_buffer(eb, chunk_tree_uuid,321 offsetof(struct btrfs_header, chunk_tree_uuid),322 BTRFS_FSID_SIZE);323}324 325static inline void write_extent_buffer_fsid(const struct extent_buffer *eb,326 const void *fsid)327{328 write_extent_buffer(eb, fsid, offsetof(struct btrfs_header, fsid),329 BTRFS_FSID_SIZE);330}331 332void copy_extent_buffer_full(const struct extent_buffer *dst,333 const struct extent_buffer *src);334void copy_extent_buffer(const struct extent_buffer *dst,335 const struct extent_buffer *src,336 unsigned long dst_offset, unsigned long src_offset,337 unsigned long len);338void memcpy_extent_buffer(const struct extent_buffer *dst,339 unsigned long dst_offset, unsigned long src_offset,340 unsigned long len);341void memmove_extent_buffer(const struct extent_buffer *dst,342 unsigned long dst_offset, unsigned long src_offset,343 unsigned long len);344void memzero_extent_buffer(const struct extent_buffer *eb, unsigned long start,345 unsigned long len);346int extent_buffer_test_bit(const struct extent_buffer *eb, unsigned long start,347 unsigned long pos);348void extent_buffer_bitmap_set(const struct extent_buffer *eb, unsigned long start,349 unsigned long pos, unsigned long len);350void extent_buffer_bitmap_clear(const struct extent_buffer *eb,351 unsigned long start, unsigned long pos,352 unsigned long len);353void set_extent_buffer_dirty(struct extent_buffer *eb);354void set_extent_buffer_uptodate(struct extent_buffer *eb);355void clear_extent_buffer_uptodate(struct extent_buffer *eb);356void extent_clear_unlock_delalloc(struct btrfs_inode *inode, u64 start, u64 end,357 const struct folio *locked_folio,358 struct extent_state **cached,359 u32 bits_to_clear, unsigned long page_ops);360int extent_invalidate_folio(struct extent_io_tree *tree,361 struct folio *folio, size_t offset);362void btrfs_clear_buffer_dirty(struct btrfs_trans_handle *trans,363 struct extent_buffer *buf);364 365int btrfs_alloc_page_array(unsigned int nr_pages, struct page **page_array,366 bool nofail);367int btrfs_alloc_folio_array(unsigned int nr_folios, struct folio **folio_array);368 369#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS370bool find_lock_delalloc_range(struct inode *inode,371 struct folio *locked_folio, u64 *start,372 u64 *end);373#endif374struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,375 u64 start);376 377#ifdef CONFIG_BTRFS_DEBUG378void btrfs_extent_buffer_leak_debug_check(struct btrfs_fs_info *fs_info);379#else380#define btrfs_extent_buffer_leak_debug_check(fs_info) do {} while (0)381#endif382 383#endif384