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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6#ifndef BTRFS_INODE_H
7#define BTRFS_INODE_H
8
9#include <linux/hash.h>
10#include <linux/refcount.h>
11#include "extent_map.h"
12#include "extent_io.h"
13#include "ordered-data.h"
14#include "delayed-inode.h"
15
16/*
17 * Since we search a directory based on f_pos (struct dir_context::pos) we have
18 * to start at 2 since '.' and '..' have f_pos of 0 and 1 respectively, so
19 * everybody else has to start at 2 (see btrfs_real_readdir() and dir_emit_dots()).
20 */
21#define BTRFS_DIR_START_INDEX 2
22
23/*
24 * ordered_data_close is set by truncate when a file that used
25 * to have good data has been truncated to zero. When it is set
26 * the btrfs file release call will add this inode to the
27 * ordered operations list so that we make sure to flush out any
28 * new data the application may have written before commit.
29 */
30enum {
31 BTRFS_INODE_FLUSH_ON_CLOSE,
32 BTRFS_INODE_DUMMY,
33 BTRFS_INODE_IN_DEFRAG,
34 BTRFS_INODE_HAS_ASYNC_EXTENT,
35 /*
36 * Always set under the VFS' inode lock, otherwise it can cause races
37 * during fsync (we start as a fast fsync and then end up in a full
38 * fsync racing with ordered extent completion).
39 */
40 BTRFS_INODE_NEEDS_FULL_SYNC,
41 BTRFS_INODE_COPY_EVERYTHING,
42 BTRFS_INODE_IN_DELALLOC_LIST,
43 BTRFS_INODE_HAS_PROPS,
44 BTRFS_INODE_SNAPSHOT_FLUSH,
45 /*
46 * Set and used when logging an inode and it serves to signal that an
47 * inode does not have xattrs, so subsequent fsyncs can avoid searching
48 * for xattrs to log. This bit must be cleared whenever a xattr is added
49 * to an inode.
50 */
51 BTRFS_INODE_NO_XATTRS,
52 /*
53 * Set when we are in a context where we need to start a transaction and
54 * have dirty pages with the respective file range locked. This is to
55 * ensure that when reserving space for the transaction, if we are low
56 * on available space and need to flush delalloc, we will not flush
57 * delalloc for this inode, because that could result in a deadlock (on
58 * the file range, inode's io_tree).
59 */
60 BTRFS_INODE_NO_DELALLOC_FLUSH,
61 /*
62 * Set when we are working on enabling verity for a file. Computing and
63 * writing the whole Merkle tree can take a while so we want to prevent
64 * races where two separate tasks attempt to simultaneously start verity
65 * on the same file.
66 */
67 BTRFS_INODE_VERITY_IN_PROGRESS,
68 /* Set when this inode is a free space inode. */
69 BTRFS_INODE_FREE_SPACE_INODE,
70};
71
72/* in memory btrfs inode */
73struct btrfs_inode {
74 /* which subvolume this inode belongs to */
75 struct btrfs_root *root;
76
77 /* key used to find this inode on disk. This is used by the code
78 * to read in roots of subvolumes
79 */
80 struct btrfs_key location;
81
82 /*
83 * Lock for counters and all fields used to determine if the inode is in
84 * the log or not (last_trans, last_sub_trans, last_log_commit,
85 * logged_trans), to access/update new_delalloc_bytes and to update the
86 * VFS' inode number of bytes used.
87 */
88 spinlock_t lock;
89
90 /* the extent_tree has caches of all the extent mappings to disk */
91 struct extent_map_tree extent_tree;
92
93 /* the io_tree does range state (DIRTY, LOCKED etc) */
94 struct extent_io_tree io_tree;
95
96 /* special utility tree used to record which mirrors have already been
97 * tried when checksums fail for a given block
98 */
99 struct rb_root io_failure_tree;
100 spinlock_t io_failure_lock;
101
102 /*
103 * Keep track of where the inode has extent items mapped in order to
104 * make sure the i_size adjustments are accurate
105 */
106 struct extent_io_tree file_extent_tree;
107
108 /* held while logging the inode in tree-log.c */
109 struct mutex log_mutex;
110
111 /* used to order data wrt metadata */
112 struct btrfs_ordered_inode_tree ordered_tree;
113
114 /* list of all the delalloc inodes in the FS. There are times we need
115 * to write all the delalloc pages to disk, and this list is used
116 * to walk them all.
117 */
118 struct list_head delalloc_inodes;
119
120 /* node for the red-black tree that links inodes in subvolume root */
121 struct rb_node rb_node;
122
123 unsigned long runtime_flags;
124
125 /* Keep track of who's O_SYNC/fsyncing currently */
126 atomic_t sync_writers;
127
128 /* full 64 bit generation number, struct vfs_inode doesn't have a big
129 * enough field for this.
130 */
131 u64 generation;
132
133 /*
134 * transid of the trans_handle that last modified this inode
135 */
136 u64 last_trans;
137
138 /*
139 * transid that last logged this inode
140 */
141 u64 logged_trans;
142
143 /*
144 * log transid when this inode was last modified
145 */
146 int last_sub_trans;
147
148 /* a local copy of root's last_log_commit */
149 int last_log_commit;
150
151 /*
152 * Total number of bytes pending delalloc, used by stat to calculate the
153 * real block usage of the file. This is used only for files.
154 */
155 u64 delalloc_bytes;
156
157 union {
158 /*
159 * Total number of bytes pending delalloc that fall within a file
160 * range that is either a hole or beyond EOF (and no prealloc extent
161 * exists in the range). This is always <= delalloc_bytes and this
162 * is used only for files.
163 */
164 u64 new_delalloc_bytes;
165 /*
166 * The offset of the last dir index key that was logged.
167 * This is used only for directories.
168 */
169 u64 last_dir_index_offset;
170 };
171
172 /*
173 * total number of bytes pending defrag, used by stat to check whether
174 * it needs COW.
175 */
176 u64 defrag_bytes;
177
178 /*
179 * the size of the file stored in the metadata on disk. data=ordered
180 * means the in-memory i_size might be larger than the size on disk
181 * because not all the blocks are written yet.
182 */
183 u64 disk_i_size;
184
185 /*
186 * If this is a directory then index_cnt is the counter for the index
187 * number for new files that are created. For an empty directory, this
188 * must be initialized to BTRFS_DIR_START_INDEX.
189 */
190 u64 index_cnt;
191
192 /* Cache the directory index number to speed the dir/file remove */
193 u64 dir_index;
194
195 /* the fsync log has some corner cases that mean we have to check
196 * directories to see if any unlinks have been done before
197 * the directory was logged. See tree-log.c for all the
198 * details
199 */
200 u64 last_unlink_trans;
201
202 /*
203 * The id/generation of the last transaction where this inode was
204 * either the source or the destination of a clone/dedupe operation.
205 * Used when logging an inode to know if there are shared extents that
206 * need special care when logging checksum items, to avoid duplicate
207 * checksum items in a log (which can lead to a corruption where we end
208 * up with missing checksum ranges after log replay).
209 * Protected by the vfs inode lock.
210 */
211 u64 last_reflink_trans;
212
213 /*
214 * Number of bytes outstanding that are going to need csums. This is
215 * used in ENOSPC accounting.
216 */
217 u64 csum_bytes;
218
219 /* Backwards incompatible flags, lower half of inode_item::flags */
220 u32 flags;
221 /* Read-only compatibility flags, upper half of inode_item::flags */
222 u32 ro_flags;
223
224 /*
225 * Counters to keep track of the number of extent item's we may use due
226 * to delalloc and such. outstanding_extents is the number of extent
227 * items we think we'll end up using, and reserved_extents is the number
228 * of extent items we've reserved metadata for.
229 */
230 unsigned outstanding_extents;
231
232 struct btrfs_block_rsv block_rsv;
233
234 /*
235 * Cached values of inode properties
236 */
237 unsigned prop_compress; /* per-file compression algorithm */
238 /*
239 * Force compression on the file using the defrag ioctl, could be
240 * different from prop_compress and takes precedence if set
241 */
242 unsigned defrag_compress;
243
244 struct btrfs_delayed_node *delayed_node;
245
246 /* File creation time. */
247 struct timespec64 i_otime;
248
249 /* Hook into fs_info->delayed_iputs */
250 struct list_head delayed_iput;
251
252 struct rw_semaphore i_mmap_lock;
253 struct inode vfs_inode;
254};
255
256static inline struct btrfs_inode *BTRFS_I(const struct inode *inode)
257{
258 return container_of(inode, struct btrfs_inode, vfs_inode);
259}
260
261static inline unsigned long btrfs_inode_hash(u64 objectid,
262 const struct btrfs_root *root)
263{
264 u64 h = objectid ^ (root->root_key.objectid * GOLDEN_RATIO_PRIME);
265
266#if BITS_PER_LONG == 32
267 h = (h >> 32) ^ (h & 0xffffffff);
268#endif
269
270 return (unsigned long)h;
271}
272
273#if BITS_PER_LONG == 32
274
275/*
276 * On 32 bit systems the i_ino of struct inode is 32 bits (unsigned long), so
277 * we use the inode's location objectid which is a u64 to avoid truncation.
278 */
279static inline u64 btrfs_ino(const struct btrfs_inode *inode)
280{
281 u64 ino = inode->location.objectid;
282
283 /* type == BTRFS_ROOT_ITEM_KEY: subvol dir */
284 if (inode->location.type == BTRFS_ROOT_ITEM_KEY)
285 ino = inode->vfs_inode.i_ino;
286 return ino;
287}
288
289#else
290
291static inline u64 btrfs_ino(const struct btrfs_inode *inode)
292{
293 return inode->vfs_inode.i_ino;
294}
295
296#endif
297
298static inline void btrfs_i_size_write(struct btrfs_inode *inode, u64 size)
299{
300 i_size_write(&inode->vfs_inode, size);
301 inode->disk_i_size = size;
302}
303
304static inline bool btrfs_is_free_space_inode(struct btrfs_inode *inode)
305{
306 return test_bit(BTRFS_INODE_FREE_SPACE_INODE, &inode->runtime_flags);
307}
308
309static inline bool is_data_inode(struct inode *inode)
310{
311 return btrfs_ino(BTRFS_I(inode)) != BTRFS_BTREE_INODE_OBJECTID;
312}
313
314static inline void btrfs_mod_outstanding_extents(struct btrfs_inode *inode,
315 int mod)
316{
317 lockdep_assert_held(&inode->lock);
318 inode->outstanding_extents += mod;
319 if (btrfs_is_free_space_inode(inode))
320 return;
321 trace_btrfs_inode_mod_outstanding_extents(inode->root, btrfs_ino(inode),
322 mod);
323}
324
325/*
326 * Called every time after doing a buffered, direct IO or memory mapped write.
327 *
328 * This is to ensure that if we write to a file that was previously fsynced in
329 * the current transaction, then try to fsync it again in the same transaction,
330 * we will know that there were changes in the file and that it needs to be
331 * logged.
332 */
333static inline void btrfs_set_inode_last_sub_trans(struct btrfs_inode *inode)
334{
335 spin_lock(&inode->lock);
336 inode->last_sub_trans = inode->root->log_transid;
337 spin_unlock(&inode->lock);
338}
339
340/*
341 * Should be called while holding the inode's VFS lock in exclusive mode or in a
342 * context where no one else can access the inode concurrently (during inode
343 * creation or when loading an inode from disk).
344 */
345static inline void btrfs_set_inode_full_sync(struct btrfs_inode *inode)
346{
347 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags);
348 /*
349 * The inode may have been part of a reflink operation in the last
350 * transaction that modified it, and then a fsync has reset the
351 * last_reflink_trans to avoid subsequent fsyncs in the same
352 * transaction to do unnecessary work. So update last_reflink_trans
353 * to the last_trans value (we have to be pessimistic and assume a
354 * reflink happened).
355 *
356 * The ->last_trans is protected by the inode's spinlock and we can
357 * have a concurrent ordered extent completion update it. Also set
358 * last_reflink_trans to ->last_trans only if the former is less than
359 * the later, because we can be called in a context where
360 * last_reflink_trans was set to the current transaction generation
361 * while ->last_trans was not yet updated in the current transaction,
362 * and therefore has a lower value.
363 */
364 spin_lock(&inode->lock);
365 if (inode->last_reflink_trans < inode->last_trans)
366 inode->last_reflink_trans = inode->last_trans;
367 spin_unlock(&inode->lock);
368}
369
370static inline bool btrfs_inode_in_log(struct btrfs_inode *inode, u64 generation)
371{
372 bool ret = false;
373
374 spin_lock(&inode->lock);
375 if (inode->logged_trans == generation &&
376 inode->last_sub_trans <= inode->last_log_commit &&
377 inode->last_sub_trans <= inode->root->last_log_commit)
378 ret = true;
379 spin_unlock(&inode->lock);
380 return ret;
381}
382
383/*
384 * Check if the inode has flags compatible with compression
385 */
386static inline bool btrfs_inode_can_compress(const struct btrfs_inode *inode)
387{
388 if (inode->flags & BTRFS_INODE_NODATACOW ||
389 inode->flags & BTRFS_INODE_NODATASUM)
390 return false;
391 return true;
392}
393
394/*
395 * btrfs_inode_item stores flags in a u64, btrfs_inode stores them in two
396 * separate u32s. These two functions convert between the two representations.
397 */
398static inline u64 btrfs_inode_combine_flags(u32 flags, u32 ro_flags)
399{
400 return (flags | ((u64)ro_flags << 32));
401}
402
403static inline void btrfs_inode_split_flags(u64 inode_item_flags,
404 u32 *flags, u32 *ro_flags)
405{
406 *flags = (u32)inode_item_flags;
407 *ro_flags = (u32)(inode_item_flags >> 32);
408}
409
410/* Array of bytes with variable length, hexadecimal format 0x1234 */
411#define CSUM_FMT "0x%*phN"
412#define CSUM_FMT_VALUE(size, bytes) size, bytes
413
414void btrfs_submit_data_write_bio(struct btrfs_inode *inode, struct bio *bio, int mirror_num);
415void btrfs_submit_data_read_bio(struct btrfs_inode *inode, struct bio *bio,
416 int mirror_num, enum btrfs_compression_type compress_type);
417void btrfs_submit_dio_repair_bio(struct btrfs_inode *inode, struct bio *bio, int mirror_num);
418blk_status_t btrfs_submit_bio_start(struct btrfs_inode *inode, struct bio *bio);
419blk_status_t btrfs_submit_bio_start_direct_io(struct btrfs_inode *inode,
420 struct bio *bio,
421 u64 dio_file_offset);
422int btrfs_check_sector_csum(struct btrfs_fs_info *fs_info, struct page *page,
423 u32 pgoff, u8 *csum, const u8 * const csum_expected);
424int btrfs_check_data_csum(struct btrfs_inode *inode, struct btrfs_bio *bbio,
425 u32 bio_offset, struct page *page, u32 pgoff);
426unsigned int btrfs_verify_data_csum(struct btrfs_bio *bbio,
427 u32 bio_offset, struct page *page,
428 u64 start, u64 end);
429noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len,
430 u64 *orig_start, u64 *orig_block_len,
431 u64 *ram_bytes, bool nowait, bool strict);
432
433void __btrfs_del_delalloc_inode(struct btrfs_root *root, struct btrfs_inode *inode);
434struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry);
435int btrfs_set_inode_index(struct btrfs_inode *dir, u64 *index);
436int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
437 struct btrfs_inode *dir, struct btrfs_inode *inode,
438 const struct fscrypt_str *name);
439int btrfs_add_link(struct btrfs_trans_handle *trans,
440 struct btrfs_inode *parent_inode, struct btrfs_inode *inode,
441 const struct fscrypt_str *name, int add_backref, u64 index);
442int btrfs_delete_subvolume(struct btrfs_inode *dir, struct dentry *dentry);
443int btrfs_truncate_block(struct btrfs_inode *inode, loff_t from, loff_t len,
444 int front);
445
446int btrfs_start_delalloc_snapshot(struct btrfs_root *root, bool in_reclaim_context);
447int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, long nr,
448 bool in_reclaim_context);
449int btrfs_set_extent_delalloc(struct btrfs_inode *inode, u64 start, u64 end,
450 unsigned int extra_bits,
451 struct extent_state **cached_state);
452
453struct btrfs_new_inode_args {
454 /* Input */
455 struct inode *dir;
456 struct dentry *dentry;
457 struct inode *inode;
458 bool orphan;
459 bool subvol;
460
461 /* Output from btrfs_new_inode_prepare(), input to btrfs_create_new_inode(). */
462 struct posix_acl *default_acl;
463 struct posix_acl *acl;
464 struct fscrypt_name fname;
465};
466
467int btrfs_new_inode_prepare(struct btrfs_new_inode_args *args,
468 unsigned int *trans_num_items);
469int btrfs_create_new_inode(struct btrfs_trans_handle *trans,
470 struct btrfs_new_inode_args *args);
471void btrfs_new_inode_args_destroy(struct btrfs_new_inode_args *args);
472struct inode *btrfs_new_subvol_inode(struct user_namespace *mnt_userns,
473 struct inode *dir);
474 void btrfs_set_delalloc_extent(struct btrfs_inode *inode, struct extent_state *state,
475 u32 bits);
476void btrfs_clear_delalloc_extent(struct btrfs_inode *inode,
477 struct extent_state *state, u32 bits);
478void btrfs_merge_delalloc_extent(struct btrfs_inode *inode, struct extent_state *new,
479 struct extent_state *other);
480void btrfs_split_delalloc_extent(struct btrfs_inode *inode,
481 struct extent_state *orig, u64 split);
482void btrfs_set_range_writeback(struct btrfs_inode *inode, u64 start, u64 end);
483vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf);
484void btrfs_evict_inode(struct inode *inode);
485struct inode *btrfs_alloc_inode(struct super_block *sb);
486void btrfs_destroy_inode(struct inode *inode);
487void btrfs_free_inode(struct inode *inode);
488int btrfs_drop_inode(struct inode *inode);
489int __init btrfs_init_cachep(void);
490void __cold btrfs_destroy_cachep(void);
491struct inode *btrfs_iget_path(struct super_block *s, u64 ino,
492 struct btrfs_root *root, struct btrfs_path *path);
493struct inode *btrfs_iget(struct super_block *s, u64 ino, struct btrfs_root *root);
494struct extent_map *btrfs_get_extent(struct btrfs_inode *inode,
495 struct page *page, size_t pg_offset,
496 u64 start, u64 end);
497int btrfs_update_inode(struct btrfs_trans_handle *trans,
498 struct btrfs_root *root, struct btrfs_inode *inode);
499int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans,
500 struct btrfs_root *root, struct btrfs_inode *inode);
501int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct btrfs_inode *inode);
502int btrfs_orphan_cleanup(struct btrfs_root *root);
503int btrfs_cont_expand(struct btrfs_inode *inode, loff_t oldsize, loff_t size);
504void btrfs_add_delayed_iput(struct btrfs_inode *inode);
505void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info);
506int btrfs_wait_on_delayed_iputs(struct btrfs_fs_info *fs_info);
507int btrfs_prealloc_file_range(struct inode *inode, int mode,
508 u64 start, u64 num_bytes, u64 min_size,
509 loff_t actual_len, u64 *alloc_hint);
510int btrfs_prealloc_file_range_trans(struct inode *inode,
511 struct btrfs_trans_handle *trans, int mode,
512 u64 start, u64 num_bytes, u64 min_size,
513 loff_t actual_len, u64 *alloc_hint);
514int btrfs_run_delalloc_range(struct btrfs_inode *inode, struct page *locked_page,
515 u64 start, u64 end, int *page_started,
516 unsigned long *nr_written, struct writeback_control *wbc);
517int btrfs_writepage_cow_fixup(struct page *page);
518void btrfs_writepage_endio_finish_ordered(struct btrfs_inode *inode,
519 struct page *page, u64 start,
520 u64 end, bool uptodate);
521int btrfs_encoded_io_compression_from_extent(struct btrfs_fs_info *fs_info,
522 int compress_type);
523int btrfs_encoded_read_regular_fill_pages(struct btrfs_inode *inode,
524 u64 file_offset, u64 disk_bytenr,
525 u64 disk_io_size,
526 struct page **pages);
527ssize_t btrfs_encoded_read(struct kiocb *iocb, struct iov_iter *iter,
528 struct btrfs_ioctl_encoded_io_args *encoded);
529ssize_t btrfs_do_encoded_write(struct kiocb *iocb, struct iov_iter *from,
530 const struct btrfs_ioctl_encoded_io_args *encoded);
531
532ssize_t btrfs_dio_read(struct kiocb *iocb, struct iov_iter *iter,
533 size_t done_before);
534struct iomap_dio *btrfs_dio_write(struct kiocb *iocb, struct iov_iter *iter,
535 size_t done_before);
536
537extern const struct dentry_operations btrfs_dentry_operations;
538
539/* Inode locking type flags, by default the exclusive lock is taken. */
540enum btrfs_ilock_type {
541 ENUM_BIT(BTRFS_ILOCK_SHARED),
542 ENUM_BIT(BTRFS_ILOCK_TRY),
543 ENUM_BIT(BTRFS_ILOCK_MMAP),
544};
545
546int btrfs_inode_lock(struct btrfs_inode *inode, unsigned int ilock_flags);
547void btrfs_inode_unlock(struct btrfs_inode *inode, unsigned int ilock_flags);
548void btrfs_update_inode_bytes(struct btrfs_inode *inode, const u64 add_bytes,
549 const u64 del_bytes);
550void btrfs_assert_inode_range_clean(struct btrfs_inode *inode, u64 start, u64 end);
551
552#endif
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6#ifndef BTRFS_INODE_H
7#define BTRFS_INODE_H
8
9#include <linux/hash.h>
10#include <linux/refcount.h>
11#include <linux/spinlock.h>
12#include <linux/mutex.h>
13#include <linux/rwsem.h>
14#include <linux/fs.h>
15#include <linux/mm.h>
16#include <linux/compiler.h>
17#include <linux/fscrypt.h>
18#include <linux/lockdep.h>
19#include <uapi/linux/btrfs_tree.h>
20#include <trace/events/btrfs.h>
21#include "block-rsv.h"
22#include "extent_map.h"
23#include "extent_io.h"
24#include "extent-io-tree.h"
25#include "ordered-data.h"
26#include "delayed-inode.h"
27
28struct extent_state;
29struct posix_acl;
30struct iov_iter;
31struct writeback_control;
32struct btrfs_root;
33struct btrfs_fs_info;
34struct btrfs_trans_handle;
35
36/*
37 * Since we search a directory based on f_pos (struct dir_context::pos) we have
38 * to start at 2 since '.' and '..' have f_pos of 0 and 1 respectively, so
39 * everybody else has to start at 2 (see btrfs_real_readdir() and dir_emit_dots()).
40 */
41#define BTRFS_DIR_START_INDEX 2
42
43/*
44 * ordered_data_close is set by truncate when a file that used
45 * to have good data has been truncated to zero. When it is set
46 * the btrfs file release call will add this inode to the
47 * ordered operations list so that we make sure to flush out any
48 * new data the application may have written before commit.
49 */
50enum {
51 BTRFS_INODE_FLUSH_ON_CLOSE,
52 BTRFS_INODE_DUMMY,
53 BTRFS_INODE_IN_DEFRAG,
54 BTRFS_INODE_HAS_ASYNC_EXTENT,
55 /*
56 * Always set under the VFS' inode lock, otherwise it can cause races
57 * during fsync (we start as a fast fsync and then end up in a full
58 * fsync racing with ordered extent completion).
59 */
60 BTRFS_INODE_NEEDS_FULL_SYNC,
61 BTRFS_INODE_COPY_EVERYTHING,
62 BTRFS_INODE_HAS_PROPS,
63 BTRFS_INODE_SNAPSHOT_FLUSH,
64 /*
65 * Set and used when logging an inode and it serves to signal that an
66 * inode does not have xattrs, so subsequent fsyncs can avoid searching
67 * for xattrs to log. This bit must be cleared whenever a xattr is added
68 * to an inode.
69 */
70 BTRFS_INODE_NO_XATTRS,
71 /*
72 * Set when we are in a context where we need to start a transaction and
73 * have dirty pages with the respective file range locked. This is to
74 * ensure that when reserving space for the transaction, if we are low
75 * on available space and need to flush delalloc, we will not flush
76 * delalloc for this inode, because that could result in a deadlock (on
77 * the file range, inode's io_tree).
78 */
79 BTRFS_INODE_NO_DELALLOC_FLUSH,
80 /*
81 * Set when we are working on enabling verity for a file. Computing and
82 * writing the whole Merkle tree can take a while so we want to prevent
83 * races where two separate tasks attempt to simultaneously start verity
84 * on the same file.
85 */
86 BTRFS_INODE_VERITY_IN_PROGRESS,
87 /* Set when this inode is a free space inode. */
88 BTRFS_INODE_FREE_SPACE_INODE,
89 /* Set when there are no capabilities in XATTs for the inode. */
90 BTRFS_INODE_NO_CAP_XATTR,
91 /*
92 * Set if an error happened when doing a COW write before submitting a
93 * bio or during writeback. Used for both buffered writes and direct IO
94 * writes. This is to signal a fast fsync that it has to wait for
95 * ordered extents to complete and therefore not log extent maps that
96 * point to unwritten extents (when an ordered extent completes and it
97 * has the BTRFS_ORDERED_IOERR flag set, it drops extent maps in its
98 * range).
99 */
100 BTRFS_INODE_COW_WRITE_ERROR,
101 /*
102 * Indicate this is a directory that points to a subvolume for which
103 * there is no root reference item. That's a case like the following:
104 *
105 * $ btrfs subvolume create /mnt/parent
106 * $ btrfs subvolume create /mnt/parent/child
107 * $ btrfs subvolume snapshot /mnt/parent /mnt/snap
108 *
109 * If subvolume "parent" is root 256, subvolume "child" is root 257 and
110 * snapshot "snap" is root 258, then there's no root reference item (key
111 * BTRFS_ROOT_REF_KEY in the root tree) for the subvolume "child"
112 * associated to root 258 (the snapshot) - there's only for the root
113 * of the "parent" subvolume (root 256). In the chunk root we have a
114 * (256 BTRFS_ROOT_REF_KEY 257) key but we don't have a
115 * (258 BTRFS_ROOT_REF_KEY 257) key - the sames goes for backrefs, we
116 * have a (257 BTRFS_ROOT_BACKREF_KEY 256) but we don't have a
117 * (257 BTRFS_ROOT_BACKREF_KEY 258) key.
118 *
119 * So when opening the "child" dentry from the snapshot's directory,
120 * we don't find a root ref item and we create a stub inode. This is
121 * done at new_simple_dir(), called from btrfs_lookup_dentry().
122 */
123 BTRFS_INODE_ROOT_STUB,
124};
125
126/* in memory btrfs inode */
127struct btrfs_inode {
128 /* which subvolume this inode belongs to */
129 struct btrfs_root *root;
130
131#if BITS_PER_LONG == 32
132 /*
133 * The objectid of the corresponding BTRFS_INODE_ITEM_KEY.
134 * On 64 bits platforms we can get it from vfs_inode.i_ino, which is an
135 * unsigned long and therefore 64 bits on such platforms.
136 */
137 u64 objectid;
138#endif
139
140 /* Cached value of inode property 'compression'. */
141 u8 prop_compress;
142
143 /*
144 * Force compression on the file using the defrag ioctl, could be
145 * different from prop_compress and takes precedence if set.
146 */
147 u8 defrag_compress;
148
149 /*
150 * Lock for counters and all fields used to determine if the inode is in
151 * the log or not (last_trans, last_sub_trans, last_log_commit,
152 * logged_trans), to access/update delalloc_bytes, new_delalloc_bytes,
153 * defrag_bytes, disk_i_size, outstanding_extents, csum_bytes and to
154 * update the VFS' inode number of bytes used.
155 * Also protects setting struct file::private_data.
156 */
157 spinlock_t lock;
158
159 /* the extent_tree has caches of all the extent mappings to disk */
160 struct extent_map_tree extent_tree;
161
162 /* the io_tree does range state (DIRTY, LOCKED etc) */
163 struct extent_io_tree io_tree;
164
165 /*
166 * Keep track of where the inode has extent items mapped in order to
167 * make sure the i_size adjustments are accurate. Not required when the
168 * filesystem is NO_HOLES, the status can't be set while mounted as
169 * it's a mkfs-time feature.
170 */
171 struct extent_io_tree *file_extent_tree;
172
173 /* held while logging the inode in tree-log.c */
174 struct mutex log_mutex;
175
176 /*
177 * Counters to keep track of the number of extent item's we may use due
178 * to delalloc and such. outstanding_extents is the number of extent
179 * items we think we'll end up using, and reserved_extents is the number
180 * of extent items we've reserved metadata for. Protected by 'lock'.
181 */
182 unsigned outstanding_extents;
183
184 /* used to order data wrt metadata */
185 spinlock_t ordered_tree_lock;
186 struct rb_root ordered_tree;
187 struct rb_node *ordered_tree_last;
188
189 /* list of all the delalloc inodes in the FS. There are times we need
190 * to write all the delalloc pages to disk, and this list is used
191 * to walk them all.
192 */
193 struct list_head delalloc_inodes;
194
195 unsigned long runtime_flags;
196
197 /* full 64 bit generation number, struct vfs_inode doesn't have a big
198 * enough field for this.
199 */
200 u64 generation;
201
202 /*
203 * ID of the transaction handle that last modified this inode.
204 * Protected by 'lock'.
205 */
206 u64 last_trans;
207
208 /*
209 * ID of the transaction that last logged this inode.
210 * Protected by 'lock'.
211 */
212 u64 logged_trans;
213
214 /*
215 * Log transaction ID when this inode was last modified.
216 * Protected by 'lock'.
217 */
218 int last_sub_trans;
219
220 /* A local copy of root's last_log_commit. Protected by 'lock'. */
221 int last_log_commit;
222
223 union {
224 /*
225 * Total number of bytes pending delalloc, used by stat to
226 * calculate the real block usage of the file. This is used
227 * only for files. Protected by 'lock'.
228 */
229 u64 delalloc_bytes;
230 /*
231 * The lowest possible index of the next dir index key which
232 * points to an inode that needs to be logged.
233 * This is used only for directories.
234 * Use the helpers btrfs_get_first_dir_index_to_log() and
235 * btrfs_set_first_dir_index_to_log() to access this field.
236 */
237 u64 first_dir_index_to_log;
238 };
239
240 union {
241 /*
242 * Total number of bytes pending delalloc that fall within a file
243 * range that is either a hole or beyond EOF (and no prealloc extent
244 * exists in the range). This is always <= delalloc_bytes and this
245 * is used only for files. Protected by 'lock'.
246 */
247 u64 new_delalloc_bytes;
248 /*
249 * The offset of the last dir index key that was logged.
250 * This is used only for directories.
251 */
252 u64 last_dir_index_offset;
253 };
254
255 union {
256 /*
257 * Total number of bytes pending defrag, used by stat to check whether
258 * it needs COW. Protected by 'lock'.
259 * Used by inodes other than the data relocation inode.
260 */
261 u64 defrag_bytes;
262
263 /*
264 * Logical address of the block group being relocated.
265 * Used only by the data relocation inode.
266 */
267 u64 reloc_block_group_start;
268 };
269
270 /*
271 * The size of the file stored in the metadata on disk. data=ordered
272 * means the in-memory i_size might be larger than the size on disk
273 * because not all the blocks are written yet. Protected by 'lock'.
274 */
275 u64 disk_i_size;
276
277 union {
278 /*
279 * If this is a directory then index_cnt is the counter for the
280 * index number for new files that are created. For an empty
281 * directory, this must be initialized to BTRFS_DIR_START_INDEX.
282 */
283 u64 index_cnt;
284
285 /*
286 * If this is not a directory, this is the number of bytes
287 * outstanding that are going to need csums. This is used in
288 * ENOSPC accounting. Protected by 'lock'.
289 */
290 u64 csum_bytes;
291 };
292
293 /* Cache the directory index number to speed the dir/file remove */
294 u64 dir_index;
295
296 /* the fsync log has some corner cases that mean we have to check
297 * directories to see if any unlinks have been done before
298 * the directory was logged. See tree-log.c for all the
299 * details
300 */
301 u64 last_unlink_trans;
302
303 union {
304 /*
305 * The id/generation of the last transaction where this inode
306 * was either the source or the destination of a clone/dedupe
307 * operation. Used when logging an inode to know if there are
308 * shared extents that need special care when logging checksum
309 * items, to avoid duplicate checksum items in a log (which can
310 * lead to a corruption where we end up with missing checksum
311 * ranges after log replay). Protected by the VFS inode lock.
312 * Used for regular files only.
313 */
314 u64 last_reflink_trans;
315
316 /*
317 * In case this a root stub inode (BTRFS_INODE_ROOT_STUB flag set),
318 * the ID of that root.
319 */
320 u64 ref_root_id;
321 };
322
323 /* Backwards incompatible flags, lower half of inode_item::flags */
324 u32 flags;
325 /* Read-only compatibility flags, upper half of inode_item::flags */
326 u32 ro_flags;
327
328 struct btrfs_block_rsv block_rsv;
329
330 struct btrfs_delayed_node *delayed_node;
331
332 /* File creation time. */
333 u64 i_otime_sec;
334 u32 i_otime_nsec;
335
336 /* Hook into fs_info->delayed_iputs */
337 struct list_head delayed_iput;
338
339 struct rw_semaphore i_mmap_lock;
340 struct inode vfs_inode;
341};
342
343static inline u64 btrfs_get_first_dir_index_to_log(const struct btrfs_inode *inode)
344{
345 return READ_ONCE(inode->first_dir_index_to_log);
346}
347
348static inline void btrfs_set_first_dir_index_to_log(struct btrfs_inode *inode,
349 u64 index)
350{
351 WRITE_ONCE(inode->first_dir_index_to_log, index);
352}
353
354/* Type checked and const-preserving VFS inode -> btrfs inode. */
355#define BTRFS_I(_inode) \
356 _Generic(_inode, \
357 struct inode *: container_of(_inode, struct btrfs_inode, vfs_inode), \
358 const struct inode *: (const struct btrfs_inode *)container_of( \
359 _inode, const struct btrfs_inode, vfs_inode))
360
361static inline unsigned long btrfs_inode_hash(u64 objectid,
362 const struct btrfs_root *root)
363{
364 u64 h = objectid ^ (root->root_key.objectid * GOLDEN_RATIO_PRIME);
365
366#if BITS_PER_LONG == 32
367 h = (h >> 32) ^ (h & 0xffffffff);
368#endif
369
370 return (unsigned long)h;
371}
372
373#if BITS_PER_LONG == 32
374
375/*
376 * On 32 bit systems the i_ino of struct inode is 32 bits (unsigned long), so
377 * we use the inode's location objectid which is a u64 to avoid truncation.
378 */
379static inline u64 btrfs_ino(const struct btrfs_inode *inode)
380{
381 u64 ino = inode->objectid;
382
383 if (test_bit(BTRFS_INODE_ROOT_STUB, &inode->runtime_flags))
384 ino = inode->vfs_inode.i_ino;
385 return ino;
386}
387
388#else
389
390static inline u64 btrfs_ino(const struct btrfs_inode *inode)
391{
392 return inode->vfs_inode.i_ino;
393}
394
395#endif
396
397static inline void btrfs_get_inode_key(const struct btrfs_inode *inode,
398 struct btrfs_key *key)
399{
400 key->objectid = btrfs_ino(inode);
401 key->type = BTRFS_INODE_ITEM_KEY;
402 key->offset = 0;
403}
404
405static inline void btrfs_set_inode_number(struct btrfs_inode *inode, u64 ino)
406{
407#if BITS_PER_LONG == 32
408 inode->objectid = ino;
409#endif
410 inode->vfs_inode.i_ino = ino;
411}
412
413static inline void btrfs_i_size_write(struct btrfs_inode *inode, u64 size)
414{
415 i_size_write(&inode->vfs_inode, size);
416 inode->disk_i_size = size;
417}
418
419static inline bool btrfs_is_free_space_inode(const struct btrfs_inode *inode)
420{
421 return test_bit(BTRFS_INODE_FREE_SPACE_INODE, &inode->runtime_flags);
422}
423
424static inline bool is_data_inode(const struct btrfs_inode *inode)
425{
426 return btrfs_ino(inode) != BTRFS_BTREE_INODE_OBJECTID;
427}
428
429static inline void btrfs_mod_outstanding_extents(struct btrfs_inode *inode,
430 int mod)
431{
432 lockdep_assert_held(&inode->lock);
433 inode->outstanding_extents += mod;
434 if (btrfs_is_free_space_inode(inode))
435 return;
436 trace_btrfs_inode_mod_outstanding_extents(inode->root, btrfs_ino(inode),
437 mod, inode->outstanding_extents);
438}
439
440/*
441 * Called every time after doing a buffered, direct IO or memory mapped write.
442 *
443 * This is to ensure that if we write to a file that was previously fsynced in
444 * the current transaction, then try to fsync it again in the same transaction,
445 * we will know that there were changes in the file and that it needs to be
446 * logged.
447 */
448static inline void btrfs_set_inode_last_sub_trans(struct btrfs_inode *inode)
449{
450 spin_lock(&inode->lock);
451 inode->last_sub_trans = inode->root->log_transid;
452 spin_unlock(&inode->lock);
453}
454
455/*
456 * Should be called while holding the inode's VFS lock in exclusive mode, or
457 * while holding the inode's mmap lock (struct btrfs_inode::i_mmap_lock) in
458 * either shared or exclusive mode, or in a context where no one else can access
459 * the inode concurrently (during inode creation or when loading an inode from
460 * disk).
461 */
462static inline void btrfs_set_inode_full_sync(struct btrfs_inode *inode)
463{
464 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags);
465 /*
466 * The inode may have been part of a reflink operation in the last
467 * transaction that modified it, and then a fsync has reset the
468 * last_reflink_trans to avoid subsequent fsyncs in the same
469 * transaction to do unnecessary work. So update last_reflink_trans
470 * to the last_trans value (we have to be pessimistic and assume a
471 * reflink happened).
472 *
473 * The ->last_trans is protected by the inode's spinlock and we can
474 * have a concurrent ordered extent completion update it. Also set
475 * last_reflink_trans to ->last_trans only if the former is less than
476 * the later, because we can be called in a context where
477 * last_reflink_trans was set to the current transaction generation
478 * while ->last_trans was not yet updated in the current transaction,
479 * and therefore has a lower value.
480 */
481 spin_lock(&inode->lock);
482 if (inode->last_reflink_trans < inode->last_trans)
483 inode->last_reflink_trans = inode->last_trans;
484 spin_unlock(&inode->lock);
485}
486
487static inline bool btrfs_inode_in_log(struct btrfs_inode *inode, u64 generation)
488{
489 bool ret = false;
490
491 spin_lock(&inode->lock);
492 if (inode->logged_trans == generation &&
493 inode->last_sub_trans <= inode->last_log_commit &&
494 inode->last_sub_trans <= btrfs_get_root_last_log_commit(inode->root))
495 ret = true;
496 spin_unlock(&inode->lock);
497 return ret;
498}
499
500/*
501 * Check if the inode has flags compatible with compression
502 */
503static inline bool btrfs_inode_can_compress(const struct btrfs_inode *inode)
504{
505 if (inode->flags & BTRFS_INODE_NODATACOW ||
506 inode->flags & BTRFS_INODE_NODATASUM)
507 return false;
508 return true;
509}
510
511static inline void btrfs_assert_inode_locked(struct btrfs_inode *inode)
512{
513 /* Immediately trigger a crash if the inode is not locked. */
514 ASSERT(inode_is_locked(&inode->vfs_inode));
515 /* Trigger a splat in dmesg if this task is not holding the lock. */
516 lockdep_assert_held(&inode->vfs_inode.i_rwsem);
517}
518
519/* Array of bytes with variable length, hexadecimal format 0x1234 */
520#define CSUM_FMT "0x%*phN"
521#define CSUM_FMT_VALUE(size, bytes) size, bytes
522
523int btrfs_check_sector_csum(struct btrfs_fs_info *fs_info, struct page *page,
524 u32 pgoff, u8 *csum, const u8 * const csum_expected);
525bool btrfs_data_csum_ok(struct btrfs_bio *bbio, struct btrfs_device *dev,
526 u32 bio_offset, struct bio_vec *bv);
527noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len,
528 struct btrfs_file_extent *file_extent,
529 bool nowait, bool strict);
530
531void btrfs_del_delalloc_inode(struct btrfs_inode *inode);
532struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry);
533int btrfs_set_inode_index(struct btrfs_inode *dir, u64 *index);
534int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
535 struct btrfs_inode *dir, struct btrfs_inode *inode,
536 const struct fscrypt_str *name);
537int btrfs_add_link(struct btrfs_trans_handle *trans,
538 struct btrfs_inode *parent_inode, struct btrfs_inode *inode,
539 const struct fscrypt_str *name, int add_backref, u64 index);
540int btrfs_delete_subvolume(struct btrfs_inode *dir, struct dentry *dentry);
541int btrfs_truncate_block(struct btrfs_inode *inode, loff_t from, loff_t len,
542 int front);
543
544int btrfs_start_delalloc_snapshot(struct btrfs_root *root, bool in_reclaim_context);
545int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, long nr,
546 bool in_reclaim_context);
547int btrfs_set_extent_delalloc(struct btrfs_inode *inode, u64 start, u64 end,
548 unsigned int extra_bits,
549 struct extent_state **cached_state);
550
551struct btrfs_new_inode_args {
552 /* Input */
553 struct inode *dir;
554 struct dentry *dentry;
555 struct inode *inode;
556 bool orphan;
557 bool subvol;
558
559 /* Output from btrfs_new_inode_prepare(), input to btrfs_create_new_inode(). */
560 struct posix_acl *default_acl;
561 struct posix_acl *acl;
562 struct fscrypt_name fname;
563};
564
565int btrfs_new_inode_prepare(struct btrfs_new_inode_args *args,
566 unsigned int *trans_num_items);
567int btrfs_create_new_inode(struct btrfs_trans_handle *trans,
568 struct btrfs_new_inode_args *args);
569void btrfs_new_inode_args_destroy(struct btrfs_new_inode_args *args);
570struct inode *btrfs_new_subvol_inode(struct mnt_idmap *idmap,
571 struct inode *dir);
572 void btrfs_set_delalloc_extent(struct btrfs_inode *inode, struct extent_state *state,
573 u32 bits);
574void btrfs_clear_delalloc_extent(struct btrfs_inode *inode,
575 struct extent_state *state, u32 bits);
576void btrfs_merge_delalloc_extent(struct btrfs_inode *inode, struct extent_state *new,
577 struct extent_state *other);
578void btrfs_split_delalloc_extent(struct btrfs_inode *inode,
579 struct extent_state *orig, u64 split);
580void btrfs_evict_inode(struct inode *inode);
581struct inode *btrfs_alloc_inode(struct super_block *sb);
582void btrfs_destroy_inode(struct inode *inode);
583void btrfs_free_inode(struct inode *inode);
584int btrfs_drop_inode(struct inode *inode);
585int __init btrfs_init_cachep(void);
586void __cold btrfs_destroy_cachep(void);
587struct inode *btrfs_iget_path(u64 ino, struct btrfs_root *root,
588 struct btrfs_path *path);
589struct inode *btrfs_iget(u64 ino, struct btrfs_root *root);
590struct extent_map *btrfs_get_extent(struct btrfs_inode *inode,
591 struct folio *folio, u64 start, u64 len);
592int btrfs_update_inode(struct btrfs_trans_handle *trans,
593 struct btrfs_inode *inode);
594int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans,
595 struct btrfs_inode *inode);
596int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct btrfs_inode *inode);
597int btrfs_orphan_cleanup(struct btrfs_root *root);
598int btrfs_cont_expand(struct btrfs_inode *inode, loff_t oldsize, loff_t size);
599void btrfs_add_delayed_iput(struct btrfs_inode *inode);
600void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info);
601int btrfs_wait_on_delayed_iputs(struct btrfs_fs_info *fs_info);
602int btrfs_prealloc_file_range(struct inode *inode, int mode,
603 u64 start, u64 num_bytes, u64 min_size,
604 loff_t actual_len, u64 *alloc_hint);
605int btrfs_prealloc_file_range_trans(struct inode *inode,
606 struct btrfs_trans_handle *trans, int mode,
607 u64 start, u64 num_bytes, u64 min_size,
608 loff_t actual_len, u64 *alloc_hint);
609int btrfs_run_delalloc_range(struct btrfs_inode *inode, struct folio *locked_folio,
610 u64 start, u64 end, struct writeback_control *wbc);
611int btrfs_writepage_cow_fixup(struct folio *folio);
612int btrfs_encoded_io_compression_from_extent(struct btrfs_fs_info *fs_info,
613 int compress_type);
614int btrfs_encoded_read_regular_fill_pages(struct btrfs_inode *inode,
615 u64 disk_bytenr, u64 disk_io_size,
616 struct page **pages, void *uring_ctx);
617ssize_t btrfs_encoded_read(struct kiocb *iocb, struct iov_iter *iter,
618 struct btrfs_ioctl_encoded_io_args *encoded,
619 struct extent_state **cached_state,
620 u64 *disk_bytenr, u64 *disk_io_size);
621ssize_t btrfs_encoded_read_regular(struct kiocb *iocb, struct iov_iter *iter,
622 u64 start, u64 lockend,
623 struct extent_state **cached_state,
624 u64 disk_bytenr, u64 disk_io_size,
625 size_t count, bool compressed, bool *unlocked);
626ssize_t btrfs_do_encoded_write(struct kiocb *iocb, struct iov_iter *from,
627 const struct btrfs_ioctl_encoded_io_args *encoded);
628
629struct btrfs_inode *btrfs_find_first_inode(struct btrfs_root *root, u64 min_ino);
630
631extern const struct dentry_operations btrfs_dentry_operations;
632
633/* Inode locking type flags, by default the exclusive lock is taken. */
634enum btrfs_ilock_type {
635 ENUM_BIT(BTRFS_ILOCK_SHARED),
636 ENUM_BIT(BTRFS_ILOCK_TRY),
637 ENUM_BIT(BTRFS_ILOCK_MMAP),
638};
639
640int btrfs_inode_lock(struct btrfs_inode *inode, unsigned int ilock_flags);
641void btrfs_inode_unlock(struct btrfs_inode *inode, unsigned int ilock_flags);
642void btrfs_update_inode_bytes(struct btrfs_inode *inode, const u64 add_bytes,
643 const u64 del_bytes);
644void btrfs_assert_inode_range_clean(struct btrfs_inode *inode, u64 start, u64 end);
645u64 btrfs_get_extent_allocation_hint(struct btrfs_inode *inode, u64 start,
646 u64 num_bytes);
647struct extent_map *btrfs_create_io_em(struct btrfs_inode *inode, u64 start,
648 const struct btrfs_file_extent *file_extent,
649 int type);
650
651#endif