Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
ac27a0ec | 2 | /* |
617ba13b | 3 | * linux/fs/ext4/file.c |
ac27a0ec DK |
4 | * |
5 | * Copyright (C) 1992, 1993, 1994, 1995 | |
6 | * Remy Card (card@masi.ibp.fr) | |
7 | * Laboratoire MASI - Institut Blaise Pascal | |
8 | * Universite Pierre et Marie Curie (Paris VI) | |
9 | * | |
10 | * from | |
11 | * | |
12 | * linux/fs/minix/file.c | |
13 | * | |
14 | * Copyright (C) 1991, 1992 Linus Torvalds | |
15 | * | |
617ba13b | 16 | * ext4 fs regular file handling primitives |
ac27a0ec DK |
17 | * |
18 | * 64-bit file support on 64-bit platforms by Jakub Jelinek | |
19 | * (jj@sunsite.ms.mff.cuni.cz) | |
20 | */ | |
21 | ||
22 | #include <linux/time.h> | |
23 | #include <linux/fs.h> | |
545052e9 | 24 | #include <linux/iomap.h> |
bc0b0d6d TT |
25 | #include <linux/mount.h> |
26 | #include <linux/path.h> | |
c94c2acf | 27 | #include <linux/dax.h> |
871a2931 | 28 | #include <linux/quotaops.h> |
c8c0df24 | 29 | #include <linux/pagevec.h> |
e2e40f2c | 30 | #include <linux/uio.h> |
b8a6176c | 31 | #include <linux/mman.h> |
378f32ba | 32 | #include <linux/backing-dev.h> |
3dcf5451 CH |
33 | #include "ext4.h" |
34 | #include "ext4_jbd2.h" | |
ac27a0ec DK |
35 | #include "xattr.h" |
36 | #include "acl.h" | |
569342dc | 37 | #include "truncate.h" |
ac27a0ec | 38 | |
b1b4705d MB |
39 | static bool ext4_dio_supported(struct inode *inode) |
40 | { | |
41 | if (IS_ENABLED(CONFIG_FS_ENCRYPTION) && IS_ENCRYPTED(inode)) | |
42 | return false; | |
43 | if (fsverity_active(inode)) | |
44 | return false; | |
45 | if (ext4_should_journal_data(inode)) | |
46 | return false; | |
47 | if (ext4_has_inline_data(inode)) | |
48 | return false; | |
49 | return true; | |
50 | } | |
51 | ||
52 | static ssize_t ext4_dio_read_iter(struct kiocb *iocb, struct iov_iter *to) | |
53 | { | |
54 | ssize_t ret; | |
55 | struct inode *inode = file_inode(iocb->ki_filp); | |
56 | ||
57 | if (iocb->ki_flags & IOCB_NOWAIT) { | |
58 | if (!inode_trylock_shared(inode)) | |
59 | return -EAGAIN; | |
60 | } else { | |
61 | inode_lock_shared(inode); | |
62 | } | |
63 | ||
64 | if (!ext4_dio_supported(inode)) { | |
65 | inode_unlock_shared(inode); | |
66 | /* | |
67 | * Fallback to buffered I/O if the operation being performed on | |
68 | * the inode is not supported by direct I/O. The IOCB_DIRECT | |
69 | * flag needs to be cleared here in order to ensure that the | |
70 | * direct I/O path within generic_file_read_iter() is not | |
71 | * taken. | |
72 | */ | |
73 | iocb->ki_flags &= ~IOCB_DIRECT; | |
74 | return generic_file_read_iter(iocb, to); | |
75 | } | |
76 | ||
77 | ret = iomap_dio_rw(iocb, to, &ext4_iomap_ops, NULL, | |
78 | is_sync_kiocb(iocb)); | |
79 | inode_unlock_shared(inode); | |
80 | ||
81 | file_accessed(iocb->ki_filp); | |
82 | return ret; | |
83 | } | |
84 | ||
364443cb JK |
85 | #ifdef CONFIG_FS_DAX |
86 | static ssize_t ext4_dax_read_iter(struct kiocb *iocb, struct iov_iter *to) | |
87 | { | |
88 | struct inode *inode = file_inode(iocb->ki_filp); | |
89 | ssize_t ret; | |
90 | ||
f629afe3 RH |
91 | if (iocb->ki_flags & IOCB_NOWAIT) { |
92 | if (!inode_trylock_shared(inode)) | |
728fbc0e | 93 | return -EAGAIN; |
f629afe3 | 94 | } else { |
728fbc0e GR |
95 | inode_lock_shared(inode); |
96 | } | |
364443cb JK |
97 | /* |
98 | * Recheck under inode lock - at this point we are sure it cannot | |
99 | * change anymore | |
100 | */ | |
101 | if (!IS_DAX(inode)) { | |
102 | inode_unlock_shared(inode); | |
103 | /* Fallback to buffered IO in case we cannot support DAX */ | |
104 | return generic_file_read_iter(iocb, to); | |
105 | } | |
106 | ret = dax_iomap_rw(iocb, to, &ext4_iomap_ops); | |
107 | inode_unlock_shared(inode); | |
108 | ||
109 | file_accessed(iocb->ki_filp); | |
110 | return ret; | |
111 | } | |
112 | #endif | |
113 | ||
114 | static ssize_t ext4_file_read_iter(struct kiocb *iocb, struct iov_iter *to) | |
115 | { | |
b1b4705d MB |
116 | struct inode *inode = file_inode(iocb->ki_filp); |
117 | ||
118 | if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) | |
0db1ff22 TT |
119 | return -EIO; |
120 | ||
364443cb JK |
121 | if (!iov_iter_count(to)) |
122 | return 0; /* skip atime */ | |
123 | ||
124 | #ifdef CONFIG_FS_DAX | |
b1b4705d | 125 | if (IS_DAX(inode)) |
364443cb JK |
126 | return ext4_dax_read_iter(iocb, to); |
127 | #endif | |
b1b4705d MB |
128 | if (iocb->ki_flags & IOCB_DIRECT) |
129 | return ext4_dio_read_iter(iocb, to); | |
130 | ||
364443cb JK |
131 | return generic_file_read_iter(iocb, to); |
132 | } | |
133 | ||
ac27a0ec DK |
134 | /* |
135 | * Called when an inode is released. Note that this is different | |
617ba13b | 136 | * from ext4_file_open: open gets called at every open, but release |
ac27a0ec DK |
137 | * gets called only when /all/ the files are closed. |
138 | */ | |
af5bc92d | 139 | static int ext4_release_file(struct inode *inode, struct file *filp) |
ac27a0ec | 140 | { |
19f5fb7a | 141 | if (ext4_test_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE)) { |
7d8f9f7d | 142 | ext4_alloc_da_blocks(inode); |
19f5fb7a | 143 | ext4_clear_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE); |
7d8f9f7d | 144 | } |
ac27a0ec DK |
145 | /* if we are the last writer on the inode, drop the block reservation */ |
146 | if ((filp->f_mode & FMODE_WRITE) && | |
d6014301 | 147 | (atomic_read(&inode->i_writecount) == 1) && |
e030a288 | 148 | !EXT4_I(inode)->i_reserved_data_blocks) { |
0e855ac8 | 149 | down_write(&EXT4_I(inode)->i_data_sem); |
27bc446e | 150 | ext4_discard_preallocations(inode, 0); |
0e855ac8 | 151 | up_write(&EXT4_I(inode)->i_data_sem); |
ac27a0ec DK |
152 | } |
153 | if (is_dx(inode) && filp->private_data) | |
617ba13b | 154 | ext4_htree_free_dir_info(filp->private_data); |
ac27a0ec DK |
155 | |
156 | return 0; | |
157 | } | |
158 | ||
e9e3bcec ES |
159 | /* |
160 | * This tests whether the IO in question is block-aligned or not. | |
161 | * Ext4 utilizes unwritten extents when hole-filling during direct IO, and they | |
162 | * are converted to written only after the IO is complete. Until they are | |
163 | * mapped, these blocks appear as holes, so dio_zero_block() will assume that | |
164 | * it needs to zero out portions of the start and/or end block. If 2 AIO | |
165 | * threads are at work on the same unwritten block, they must be synchronized | |
166 | * or one thread will zero the other's data, causing corruption. | |
167 | */ | |
aa9714d0 RH |
168 | static bool |
169 | ext4_unaligned_io(struct inode *inode, struct iov_iter *from, loff_t pos) | |
e9e3bcec ES |
170 | { |
171 | struct super_block *sb = inode->i_sb; | |
aa9714d0 | 172 | unsigned long blockmask = sb->s_blocksize - 1; |
e9e3bcec | 173 | |
9b884164 | 174 | if ((pos | iov_iter_alignment(from)) & blockmask) |
aa9714d0 | 175 | return true; |
e9e3bcec | 176 | |
aa9714d0 RH |
177 | return false; |
178 | } | |
179 | ||
180 | static bool | |
181 | ext4_extending_io(struct inode *inode, loff_t offset, size_t len) | |
182 | { | |
183 | if (offset + len > i_size_read(inode) || | |
184 | offset + len > EXT4_I(inode)->i_disksize) | |
185 | return true; | |
186 | return false; | |
e9e3bcec ES |
187 | } |
188 | ||
213bcd9c JK |
189 | /* Is IO overwriting allocated and initialized blocks? */ |
190 | static bool ext4_overwrite_io(struct inode *inode, loff_t pos, loff_t len) | |
191 | { | |
192 | struct ext4_map_blocks map; | |
193 | unsigned int blkbits = inode->i_blkbits; | |
194 | int err, blklen; | |
195 | ||
196 | if (pos + len > i_size_read(inode)) | |
197 | return false; | |
198 | ||
199 | map.m_lblk = pos >> blkbits; | |
200 | map.m_len = EXT4_MAX_BLOCKS(len, pos, blkbits); | |
201 | blklen = map.m_len; | |
202 | ||
203 | err = ext4_map_blocks(NULL, inode, &map, 0); | |
204 | /* | |
205 | * 'err==len' means that all of the blocks have been preallocated, | |
206 | * regardless of whether they have been initialized or not. To exclude | |
207 | * unwritten extents, we need to check m_flags. | |
208 | */ | |
209 | return err == blklen && (map.m_flags & EXT4_MAP_MAPPED); | |
210 | } | |
211 | ||
aa9714d0 RH |
212 | static ssize_t ext4_generic_write_checks(struct kiocb *iocb, |
213 | struct iov_iter *from) | |
213bcd9c JK |
214 | { |
215 | struct inode *inode = file_inode(iocb->ki_filp); | |
216 | ssize_t ret; | |
217 | ||
378f32ba MB |
218 | if (unlikely(IS_IMMUTABLE(inode))) |
219 | return -EPERM; | |
220 | ||
213bcd9c JK |
221 | ret = generic_write_checks(iocb, from); |
222 | if (ret <= 0) | |
223 | return ret; | |
02b016ca | 224 | |
213bcd9c JK |
225 | /* |
226 | * If we have encountered a bitmap-format file, the size limit | |
227 | * is smaller than s_maxbytes, which is for extent-mapped files. | |
228 | */ | |
229 | if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) { | |
230 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
231 | ||
232 | if (iocb->ki_pos >= sbi->s_bitmap_maxbytes) | |
233 | return -EFBIG; | |
234 | iov_iter_truncate(from, sbi->s_bitmap_maxbytes - iocb->ki_pos); | |
235 | } | |
378f32ba | 236 | |
aa9714d0 RH |
237 | return iov_iter_count(from); |
238 | } | |
239 | ||
240 | static ssize_t ext4_write_checks(struct kiocb *iocb, struct iov_iter *from) | |
241 | { | |
242 | ssize_t ret, count; | |
243 | ||
244 | count = ext4_generic_write_checks(iocb, from); | |
245 | if (count <= 0) | |
246 | return count; | |
247 | ||
378f32ba MB |
248 | ret = file_modified(iocb->ki_filp); |
249 | if (ret) | |
250 | return ret; | |
aa9714d0 | 251 | return count; |
213bcd9c JK |
252 | } |
253 | ||
378f32ba MB |
254 | static ssize_t ext4_buffered_write_iter(struct kiocb *iocb, |
255 | struct iov_iter *from) | |
256 | { | |
257 | ssize_t ret; | |
258 | struct inode *inode = file_inode(iocb->ki_filp); | |
259 | ||
260 | if (iocb->ki_flags & IOCB_NOWAIT) | |
261 | return -EOPNOTSUPP; | |
262 | ||
aa75f4d3 | 263 | ext4_fc_start_update(inode); |
378f32ba MB |
264 | inode_lock(inode); |
265 | ret = ext4_write_checks(iocb, from); | |
266 | if (ret <= 0) | |
267 | goto out; | |
268 | ||
269 | current->backing_dev_info = inode_to_bdi(inode); | |
270 | ret = generic_perform_write(iocb->ki_filp, from, iocb->ki_pos); | |
271 | current->backing_dev_info = NULL; | |
272 | ||
273 | out: | |
274 | inode_unlock(inode); | |
aa75f4d3 | 275 | ext4_fc_stop_update(inode); |
378f32ba MB |
276 | if (likely(ret > 0)) { |
277 | iocb->ki_pos += ret; | |
278 | ret = generic_write_sync(iocb, ret); | |
279 | } | |
280 | ||
281 | return ret; | |
282 | } | |
283 | ||
569342dc MB |
284 | static ssize_t ext4_handle_inode_extension(struct inode *inode, loff_t offset, |
285 | ssize_t written, size_t count) | |
286 | { | |
287 | handle_t *handle; | |
288 | bool truncate = false; | |
289 | u8 blkbits = inode->i_blkbits; | |
290 | ext4_lblk_t written_blk, end_blk; | |
4209ae12 | 291 | int ret; |
569342dc MB |
292 | |
293 | /* | |
294 | * Note that EXT4_I(inode)->i_disksize can get extended up to | |
295 | * inode->i_size while the I/O was running due to writeback of delalloc | |
296 | * blocks. But, the code in ext4_iomap_alloc() is careful to use | |
297 | * zeroed/unwritten extents if this is possible; thus we won't leave | |
298 | * uninitialized blocks in a file even if we didn't succeed in writing | |
299 | * as much as we intended. | |
300 | */ | |
301 | WARN_ON_ONCE(i_size_read(inode) < EXT4_I(inode)->i_disksize); | |
302 | if (offset + count <= EXT4_I(inode)->i_disksize) { | |
303 | /* | |
304 | * We need to ensure that the inode is removed from the orphan | |
305 | * list if it has been added prematurely, due to writeback of | |
306 | * delalloc blocks. | |
307 | */ | |
308 | if (!list_empty(&EXT4_I(inode)->i_orphan) && inode->i_nlink) { | |
309 | handle = ext4_journal_start(inode, EXT4_HT_INODE, 2); | |
310 | ||
311 | if (IS_ERR(handle)) { | |
312 | ext4_orphan_del(NULL, inode); | |
313 | return PTR_ERR(handle); | |
314 | } | |
315 | ||
316 | ext4_orphan_del(handle, inode); | |
317 | ext4_journal_stop(handle); | |
318 | } | |
319 | ||
320 | return written; | |
321 | } | |
322 | ||
323 | if (written < 0) | |
324 | goto truncate; | |
325 | ||
326 | handle = ext4_journal_start(inode, EXT4_HT_INODE, 2); | |
327 | if (IS_ERR(handle)) { | |
328 | written = PTR_ERR(handle); | |
329 | goto truncate; | |
330 | } | |
331 | ||
4209ae12 HS |
332 | if (ext4_update_inode_size(inode, offset + written)) { |
333 | ret = ext4_mark_inode_dirty(handle, inode); | |
334 | if (unlikely(ret)) { | |
335 | written = ret; | |
336 | ext4_journal_stop(handle); | |
337 | goto truncate; | |
338 | } | |
339 | } | |
569342dc MB |
340 | |
341 | /* | |
342 | * We may need to truncate allocated but not written blocks beyond EOF. | |
343 | */ | |
344 | written_blk = ALIGN(offset + written, 1 << blkbits); | |
345 | end_blk = ALIGN(offset + count, 1 << blkbits); | |
346 | if (written_blk < end_blk && ext4_can_truncate(inode)) | |
347 | truncate = true; | |
348 | ||
349 | /* | |
350 | * Remove the inode from the orphan list if it has been extended and | |
351 | * everything went OK. | |
352 | */ | |
353 | if (!truncate && inode->i_nlink) | |
354 | ext4_orphan_del(handle, inode); | |
355 | ext4_journal_stop(handle); | |
356 | ||
357 | if (truncate) { | |
358 | truncate: | |
359 | ext4_truncate_failed_write(inode); | |
360 | /* | |
361 | * If the truncate operation failed early, then the inode may | |
362 | * still be on the orphan list. In that case, we need to try | |
363 | * remove the inode from the in-memory linked list. | |
364 | */ | |
365 | if (inode->i_nlink) | |
366 | ext4_orphan_del(NULL, inode); | |
367 | } | |
368 | ||
369 | return written; | |
370 | } | |
371 | ||
378f32ba MB |
372 | static int ext4_dio_write_end_io(struct kiocb *iocb, ssize_t size, |
373 | int error, unsigned int flags) | |
374 | { | |
375 | loff_t offset = iocb->ki_pos; | |
376 | struct inode *inode = file_inode(iocb->ki_filp); | |
377 | ||
378 | if (error) | |
379 | return error; | |
380 | ||
381 | if (size && flags & IOMAP_DIO_UNWRITTEN) | |
382 | return ext4_convert_unwritten_extents(NULL, inode, | |
383 | offset, size); | |
384 | ||
385 | return 0; | |
386 | } | |
387 | ||
388 | static const struct iomap_dio_ops ext4_dio_write_ops = { | |
389 | .end_io = ext4_dio_write_end_io, | |
390 | }; | |
391 | ||
aa9714d0 RH |
392 | /* |
393 | * The intention here is to start with shared lock acquired then see if any | |
394 | * condition requires an exclusive inode lock. If yes, then we restart the | |
395 | * whole operation by releasing the shared lock and acquiring exclusive lock. | |
396 | * | |
397 | * - For unaligned_io we never take shared lock as it may cause data corruption | |
398 | * when two unaligned IO tries to modify the same block e.g. while zeroing. | |
399 | * | |
400 | * - For extending writes case we don't take the shared lock, since it requires | |
401 | * updating inode i_disksize and/or orphan handling with exclusive lock. | |
402 | * | |
bc6385da RH |
403 | * - shared locking will only be true mostly with overwrites. Otherwise we will |
404 | * switch to exclusive i_rwsem lock. | |
aa9714d0 RH |
405 | */ |
406 | static ssize_t ext4_dio_write_checks(struct kiocb *iocb, struct iov_iter *from, | |
407 | bool *ilock_shared, bool *extend) | |
408 | { | |
409 | struct file *file = iocb->ki_filp; | |
410 | struct inode *inode = file_inode(file); | |
411 | loff_t offset; | |
412 | size_t count; | |
413 | ssize_t ret; | |
414 | ||
415 | restart: | |
416 | ret = ext4_generic_write_checks(iocb, from); | |
417 | if (ret <= 0) | |
418 | goto out; | |
419 | ||
420 | offset = iocb->ki_pos; | |
421 | count = ret; | |
422 | if (ext4_extending_io(inode, offset, count)) | |
423 | *extend = true; | |
424 | /* | |
425 | * Determine whether the IO operation will overwrite allocated | |
bc6385da | 426 | * and initialized blocks. |
aa9714d0 RH |
427 | * We need exclusive i_rwsem for changing security info |
428 | * in file_modified(). | |
429 | */ | |
430 | if (*ilock_shared && (!IS_NOSEC(inode) || *extend || | |
aa9714d0 | 431 | !ext4_overwrite_io(inode, offset, count))) { |
0b3171b6 JK |
432 | if (iocb->ki_flags & IOCB_NOWAIT) { |
433 | ret = -EAGAIN; | |
434 | goto out; | |
435 | } | |
aa9714d0 RH |
436 | inode_unlock_shared(inode); |
437 | *ilock_shared = false; | |
438 | inode_lock(inode); | |
439 | goto restart; | |
440 | } | |
441 | ||
442 | ret = file_modified(file); | |
443 | if (ret < 0) | |
444 | goto out; | |
445 | ||
446 | return count; | |
447 | out: | |
448 | if (*ilock_shared) | |
449 | inode_unlock_shared(inode); | |
450 | else | |
451 | inode_unlock(inode); | |
452 | return ret; | |
453 | } | |
454 | ||
378f32ba MB |
455 | static ssize_t ext4_dio_write_iter(struct kiocb *iocb, struct iov_iter *from) |
456 | { | |
457 | ssize_t ret; | |
378f32ba MB |
458 | handle_t *handle; |
459 | struct inode *inode = file_inode(iocb->ki_filp); | |
aa9714d0 RH |
460 | loff_t offset = iocb->ki_pos; |
461 | size_t count = iov_iter_count(from); | |
8cd115bd | 462 | const struct iomap_ops *iomap_ops = &ext4_iomap_ops; |
aa9714d0 RH |
463 | bool extend = false, unaligned_io = false; |
464 | bool ilock_shared = true; | |
465 | ||
466 | /* | |
467 | * We initially start with shared inode lock unless it is | |
468 | * unaligned IO which needs exclusive lock anyways. | |
469 | */ | |
470 | if (ext4_unaligned_io(inode, from, offset)) { | |
471 | unaligned_io = true; | |
472 | ilock_shared = false; | |
473 | } | |
474 | /* | |
475 | * Quick check here without any i_rwsem lock to see if it is extending | |
476 | * IO. A more reliable check is done in ext4_dio_write_checks() with | |
477 | * proper locking in place. | |
478 | */ | |
479 | if (offset + count > i_size_read(inode)) | |
480 | ilock_shared = false; | |
378f32ba MB |
481 | |
482 | if (iocb->ki_flags & IOCB_NOWAIT) { | |
aa9714d0 RH |
483 | if (ilock_shared) { |
484 | if (!inode_trylock_shared(inode)) | |
485 | return -EAGAIN; | |
486 | } else { | |
487 | if (!inode_trylock(inode)) | |
488 | return -EAGAIN; | |
489 | } | |
378f32ba | 490 | } else { |
aa9714d0 RH |
491 | if (ilock_shared) |
492 | inode_lock_shared(inode); | |
493 | else | |
494 | inode_lock(inode); | |
378f32ba MB |
495 | } |
496 | ||
aa9714d0 | 497 | /* Fallback to buffered I/O if the inode does not support direct I/O. */ |
378f32ba | 498 | if (!ext4_dio_supported(inode)) { |
aa9714d0 RH |
499 | if (ilock_shared) |
500 | inode_unlock_shared(inode); | |
501 | else | |
502 | inode_unlock(inode); | |
378f32ba MB |
503 | return ext4_buffered_write_iter(iocb, from); |
504 | } | |
505 | ||
aa9714d0 RH |
506 | ret = ext4_dio_write_checks(iocb, from, &ilock_shared, &extend); |
507 | if (ret <= 0) | |
378f32ba | 508 | return ret; |
378f32ba | 509 | |
6e014c62 JA |
510 | /* if we're going to block and IOCB_NOWAIT is set, return -EAGAIN */ |
511 | if ((iocb->ki_flags & IOCB_NOWAIT) && (unaligned_io || extend)) { | |
512 | ret = -EAGAIN; | |
513 | goto out; | |
514 | } | |
515 | ||
378f32ba | 516 | offset = iocb->ki_pos; |
aa9714d0 | 517 | count = ret; |
378f32ba MB |
518 | |
519 | /* | |
aa9714d0 RH |
520 | * Unaligned direct IO must be serialized among each other as zeroing |
521 | * of partial blocks of two competing unaligned IOs can result in data | |
522 | * corruption. | |
523 | * | |
524 | * So we make sure we don't allow any unaligned IO in flight. | |
525 | * For IOs where we need not wait (like unaligned non-AIO DIO), | |
526 | * below inode_dio_wait() may anyway become a no-op, since we start | |
527 | * with exclusive lock. | |
378f32ba | 528 | */ |
aa9714d0 RH |
529 | if (unaligned_io) |
530 | inode_dio_wait(inode); | |
378f32ba | 531 | |
aa9714d0 | 532 | if (extend) { |
378f32ba MB |
533 | handle = ext4_journal_start(inode, EXT4_HT_INODE, 2); |
534 | if (IS_ERR(handle)) { | |
535 | ret = PTR_ERR(handle); | |
536 | goto out; | |
537 | } | |
538 | ||
aa75f4d3 | 539 | ext4_fc_start_update(inode); |
378f32ba | 540 | ret = ext4_orphan_add(handle, inode); |
aa75f4d3 | 541 | ext4_fc_stop_update(inode); |
378f32ba MB |
542 | if (ret) { |
543 | ext4_journal_stop(handle); | |
544 | goto out; | |
545 | } | |
546 | ||
378f32ba MB |
547 | ext4_journal_stop(handle); |
548 | } | |
549 | ||
8cd115bd JK |
550 | if (ilock_shared) |
551 | iomap_ops = &ext4_iomap_overwrite_ops; | |
552 | ret = iomap_dio_rw(iocb, from, iomap_ops, &ext4_dio_write_ops, | |
aa9714d0 | 553 | is_sync_kiocb(iocb) || unaligned_io || extend); |
60263d58 CH |
554 | if (ret == -ENOTBLK) |
555 | ret = 0; | |
378f32ba MB |
556 | |
557 | if (extend) | |
558 | ret = ext4_handle_inode_extension(inode, offset, ret, count); | |
559 | ||
560 | out: | |
aa9714d0 | 561 | if (ilock_shared) |
378f32ba MB |
562 | inode_unlock_shared(inode); |
563 | else | |
564 | inode_unlock(inode); | |
565 | ||
566 | if (ret >= 0 && iov_iter_count(from)) { | |
567 | ssize_t err; | |
568 | loff_t endbyte; | |
569 | ||
570 | offset = iocb->ki_pos; | |
571 | err = ext4_buffered_write_iter(iocb, from); | |
572 | if (err < 0) | |
573 | return err; | |
574 | ||
575 | /* | |
576 | * We need to ensure that the pages within the page cache for | |
577 | * the range covered by this I/O are written to disk and | |
578 | * invalidated. This is in attempt to preserve the expected | |
579 | * direct I/O semantics in the case we fallback to buffered I/O | |
580 | * to complete off the I/O request. | |
581 | */ | |
582 | ret += err; | |
583 | endbyte = offset + err - 1; | |
584 | err = filemap_write_and_wait_range(iocb->ki_filp->f_mapping, | |
585 | offset, endbyte); | |
586 | if (!err) | |
587 | invalidate_mapping_pages(iocb->ki_filp->f_mapping, | |
588 | offset >> PAGE_SHIFT, | |
589 | endbyte >> PAGE_SHIFT); | |
590 | } | |
591 | ||
592 | return ret; | |
593 | } | |
594 | ||
776722e8 JK |
595 | #ifdef CONFIG_FS_DAX |
596 | static ssize_t | |
597 | ext4_dax_write_iter(struct kiocb *iocb, struct iov_iter *from) | |
598 | { | |
776722e8 | 599 | ssize_t ret; |
569342dc MB |
600 | size_t count; |
601 | loff_t offset; | |
0b9f230b MB |
602 | handle_t *handle; |
603 | bool extend = false; | |
569342dc | 604 | struct inode *inode = file_inode(iocb->ki_filp); |
776722e8 | 605 | |
f629afe3 RH |
606 | if (iocb->ki_flags & IOCB_NOWAIT) { |
607 | if (!inode_trylock(inode)) | |
728fbc0e | 608 | return -EAGAIN; |
f629afe3 | 609 | } else { |
728fbc0e GR |
610 | inode_lock(inode); |
611 | } | |
378f32ba | 612 | |
776722e8 JK |
613 | ret = ext4_write_checks(iocb, from); |
614 | if (ret <= 0) | |
615 | goto out; | |
776722e8 | 616 | |
569342dc MB |
617 | offset = iocb->ki_pos; |
618 | count = iov_iter_count(from); | |
0b9f230b MB |
619 | |
620 | if (offset + count > EXT4_I(inode)->i_disksize) { | |
621 | handle = ext4_journal_start(inode, EXT4_HT_INODE, 2); | |
622 | if (IS_ERR(handle)) { | |
623 | ret = PTR_ERR(handle); | |
624 | goto out; | |
625 | } | |
626 | ||
627 | ret = ext4_orphan_add(handle, inode); | |
628 | if (ret) { | |
629 | ext4_journal_stop(handle); | |
630 | goto out; | |
631 | } | |
632 | ||
633 | extend = true; | |
634 | ext4_journal_stop(handle); | |
635 | } | |
636 | ||
776722e8 | 637 | ret = dax_iomap_rw(iocb, from, &ext4_iomap_ops); |
0b9f230b MB |
638 | |
639 | if (extend) | |
640 | ret = ext4_handle_inode_extension(inode, offset, ret, count); | |
776722e8 | 641 | out: |
ff5462e3 | 642 | inode_unlock(inode); |
776722e8 JK |
643 | if (ret > 0) |
644 | ret = generic_write_sync(iocb, ret); | |
645 | return ret; | |
646 | } | |
647 | #endif | |
648 | ||
ac27a0ec | 649 | static ssize_t |
9b884164 | 650 | ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from) |
ac27a0ec | 651 | { |
8ad2850f | 652 | struct inode *inode = file_inode(iocb->ki_filp); |
7608e610 | 653 | |
0db1ff22 TT |
654 | if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) |
655 | return -EIO; | |
656 | ||
776722e8 JK |
657 | #ifdef CONFIG_FS_DAX |
658 | if (IS_DAX(inode)) | |
659 | return ext4_dax_write_iter(iocb, from); | |
660 | #endif | |
378f32ba MB |
661 | if (iocb->ki_flags & IOCB_DIRECT) |
662 | return ext4_dio_write_iter(iocb, from); | |
aa75f4d3 HS |
663 | else |
664 | return ext4_buffered_write_iter(iocb, from); | |
ac27a0ec DK |
665 | } |
666 | ||
923ae0ff | 667 | #ifdef CONFIG_FS_DAX |
71fe9899 | 668 | static vm_fault_t ext4_dax_huge_fault(struct vm_fault *vmf, |
c791ace1 | 669 | enum page_entry_size pe_size) |
923ae0ff | 670 | { |
71fe9899 SJ |
671 | int error = 0; |
672 | vm_fault_t result; | |
22446423 | 673 | int retries = 0; |
fb26a1cb | 674 | handle_t *handle = NULL; |
11bac800 | 675 | struct inode *inode = file_inode(vmf->vma->vm_file); |
ea3d7209 | 676 | struct super_block *sb = inode->i_sb; |
fd96b8da RD |
677 | |
678 | /* | |
679 | * We have to distinguish real writes from writes which will result in a | |
680 | * COW page; COW writes should *not* poke the journal (the file will not | |
681 | * be changed). Doing so would cause unintended failures when mounted | |
682 | * read-only. | |
683 | * | |
684 | * We check for VM_SHARED rather than vmf->cow_page since the latter is | |
685 | * unset for pe_size != PE_SIZE_PTE (i.e. only in do_cow_fault); for | |
686 | * other sizes, dax_iomap_fault will handle splitting / fallback so that | |
687 | * we eventually come back with a COW page. | |
688 | */ | |
689 | bool write = (vmf->flags & FAULT_FLAG_WRITE) && | |
690 | (vmf->vma->vm_flags & VM_SHARED); | |
b8a6176c | 691 | pfn_t pfn; |
01a33b4a MW |
692 | |
693 | if (write) { | |
694 | sb_start_pagefault(sb); | |
11bac800 | 695 | file_update_time(vmf->vma->vm_file); |
fb26a1cb | 696 | down_read(&EXT4_I(inode)->i_mmap_sem); |
22446423 | 697 | retry: |
fb26a1cb JK |
698 | handle = ext4_journal_start_sb(sb, EXT4_HT_WRITE_PAGE, |
699 | EXT4_DATA_TRANS_BLOCKS(sb)); | |
497f6926 JK |
700 | if (IS_ERR(handle)) { |
701 | up_read(&EXT4_I(inode)->i_mmap_sem); | |
702 | sb_end_pagefault(sb); | |
703 | return VM_FAULT_SIGBUS; | |
704 | } | |
fb26a1cb JK |
705 | } else { |
706 | down_read(&EXT4_I(inode)->i_mmap_sem); | |
1db17542 | 707 | } |
22446423 | 708 | result = dax_iomap_fault(vmf, pe_size, &pfn, &error, &ext4_iomap_ops); |
fb26a1cb | 709 | if (write) { |
497f6926 | 710 | ext4_journal_stop(handle); |
22446423 JK |
711 | |
712 | if ((result & VM_FAULT_ERROR) && error == -ENOSPC && | |
713 | ext4_should_retry_alloc(sb, &retries)) | |
714 | goto retry; | |
b8a6176c JK |
715 | /* Handling synchronous page fault? */ |
716 | if (result & VM_FAULT_NEEDDSYNC) | |
717 | result = dax_finish_sync_fault(vmf, pe_size, pfn); | |
fb26a1cb | 718 | up_read(&EXT4_I(inode)->i_mmap_sem); |
01a33b4a | 719 | sb_end_pagefault(sb); |
fb26a1cb JK |
720 | } else { |
721 | up_read(&EXT4_I(inode)->i_mmap_sem); | |
722 | } | |
01a33b4a MW |
723 | |
724 | return result; | |
923ae0ff RZ |
725 | } |
726 | ||
71fe9899 | 727 | static vm_fault_t ext4_dax_fault(struct vm_fault *vmf) |
c791ace1 DJ |
728 | { |
729 | return ext4_dax_huge_fault(vmf, PE_SIZE_PTE); | |
730 | } | |
731 | ||
923ae0ff RZ |
732 | static const struct vm_operations_struct ext4_dax_vm_ops = { |
733 | .fault = ext4_dax_fault, | |
c791ace1 | 734 | .huge_fault = ext4_dax_huge_fault, |
1e9d180b | 735 | .page_mkwrite = ext4_dax_fault, |
91d25ba8 | 736 | .pfn_mkwrite = ext4_dax_fault, |
923ae0ff RZ |
737 | }; |
738 | #else | |
739 | #define ext4_dax_vm_ops ext4_file_vm_ops | |
740 | #endif | |
741 | ||
f0f37e2f | 742 | static const struct vm_operations_struct ext4_file_vm_ops = { |
ea3d7209 | 743 | .fault = ext4_filemap_fault, |
f1820361 | 744 | .map_pages = filemap_map_pages, |
2e9ee850 AK |
745 | .page_mkwrite = ext4_page_mkwrite, |
746 | }; | |
747 | ||
748 | static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma) | |
749 | { | |
c9c7429c | 750 | struct inode *inode = file->f_mapping->host; |
e46bfc3f PG |
751 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
752 | struct dax_device *dax_dev = sbi->s_daxdev; | |
c9c7429c | 753 | |
e46bfc3f | 754 | if (unlikely(ext4_forced_shutdown(sbi))) |
0db1ff22 TT |
755 | return -EIO; |
756 | ||
b8a6176c | 757 | /* |
e46bfc3f PG |
758 | * We don't support synchronous mappings for non-DAX files and |
759 | * for DAX files if underneath dax_device is not synchronous. | |
b8a6176c | 760 | */ |
e46bfc3f | 761 | if (!daxdev_mapping_supported(vma, dax_dev)) |
b8a6176c JK |
762 | return -EOPNOTSUPP; |
763 | ||
2e9ee850 | 764 | file_accessed(file); |
923ae0ff RZ |
765 | if (IS_DAX(file_inode(file))) { |
766 | vma->vm_ops = &ext4_dax_vm_ops; | |
e1fb4a08 | 767 | vma->vm_flags |= VM_HUGEPAGE; |
923ae0ff RZ |
768 | } else { |
769 | vma->vm_ops = &ext4_file_vm_ops; | |
770 | } | |
2e9ee850 AK |
771 | return 0; |
772 | } | |
773 | ||
833a9508 AG |
774 | static int ext4_sample_last_mounted(struct super_block *sb, |
775 | struct vfsmount *mnt) | |
bc0b0d6d | 776 | { |
833a9508 | 777 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
bc0b0d6d TT |
778 | struct path path; |
779 | char buf[64], *cp; | |
833a9508 AG |
780 | handle_t *handle; |
781 | int err; | |
782 | ||
9b5f6c9b | 783 | if (likely(ext4_test_mount_flag(sb, EXT4_MF_MNTDIR_SAMPLED))) |
833a9508 AG |
784 | return 0; |
785 | ||
db6516a5 | 786 | if (sb_rdonly(sb) || !sb_start_intwrite_trylock(sb)) |
833a9508 AG |
787 | return 0; |
788 | ||
9b5f6c9b | 789 | ext4_set_mount_flag(sb, EXT4_MF_MNTDIR_SAMPLED); |
833a9508 AG |
790 | /* |
791 | * Sample where the filesystem has been mounted and | |
792 | * store it in the superblock for sysadmin convenience | |
793 | * when trying to sort through large numbers of block | |
794 | * devices or filesystem images. | |
795 | */ | |
796 | memset(buf, 0, sizeof(buf)); | |
797 | path.mnt = mnt; | |
798 | path.dentry = mnt->mnt_root; | |
799 | cp = d_path(&path, buf, sizeof(buf)); | |
db6516a5 | 800 | err = 0; |
833a9508 | 801 | if (IS_ERR(cp)) |
db6516a5 | 802 | goto out; |
833a9508 AG |
803 | |
804 | handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1); | |
db6516a5 | 805 | err = PTR_ERR(handle); |
833a9508 | 806 | if (IS_ERR(handle)) |
db6516a5 | 807 | goto out; |
833a9508 AG |
808 | BUFFER_TRACE(sbi->s_sbh, "get_write_access"); |
809 | err = ext4_journal_get_write_access(handle, sbi->s_sbh); | |
810 | if (err) | |
db6516a5 | 811 | goto out_journal; |
05c2c00f | 812 | lock_buffer(sbi->s_sbh); |
5a3b590d | 813 | strncpy(sbi->s_es->s_last_mounted, cp, |
833a9508 | 814 | sizeof(sbi->s_es->s_last_mounted)); |
05c2c00f JK |
815 | ext4_superblock_csum_set(sb); |
816 | unlock_buffer(sbi->s_sbh); | |
a3f5cf14 | 817 | ext4_handle_dirty_metadata(handle, NULL, sbi->s_sbh); |
db6516a5 | 818 | out_journal: |
833a9508 | 819 | ext4_journal_stop(handle); |
db6516a5 AG |
820 | out: |
821 | sb_end_intwrite(sb); | |
833a9508 AG |
822 | return err; |
823 | } | |
824 | ||
e030a288 | 825 | static int ext4_file_open(struct inode *inode, struct file *filp) |
833a9508 | 826 | { |
c9c7429c | 827 | int ret; |
bc0b0d6d | 828 | |
0db1ff22 TT |
829 | if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) |
830 | return -EIO; | |
831 | ||
833a9508 AG |
832 | ret = ext4_sample_last_mounted(inode->i_sb, filp->f_path.mnt); |
833 | if (ret) | |
834 | return ret; | |
9dd78d8c | 835 | |
09a5c31c EB |
836 | ret = fscrypt_file_open(inode, filp); |
837 | if (ret) | |
c93d8f88 EB |
838 | return ret; |
839 | ||
840 | ret = fsverity_file_open(inode, filp); | |
841 | if (ret) | |
09a5c31c EB |
842 | return ret; |
843 | ||
8aefcd55 TT |
844 | /* |
845 | * Set up the jbd2_inode if we are opening the inode for | |
846 | * writing and the journal is present | |
847 | */ | |
a361293f | 848 | if (filp->f_mode & FMODE_WRITE) { |
c9c7429c | 849 | ret = ext4_inode_attach_jinode(inode); |
a361293f JK |
850 | if (ret < 0) |
851 | return ret; | |
8aefcd55 | 852 | } |
728fbc0e | 853 | |
766ef1e1 | 854 | filp->f_mode |= FMODE_NOWAIT | FMODE_BUF_RASYNC; |
abdd438b | 855 | return dquot_file_open(inode, filp); |
bc0b0d6d TT |
856 | } |
857 | ||
e0d10bfa | 858 | /* |
ec7268ce ES |
859 | * ext4_llseek() handles both block-mapped and extent-mapped maxbytes values |
860 | * by calling generic_file_llseek_size() with the appropriate maxbytes | |
861 | * value for each. | |
e0d10bfa | 862 | */ |
965c8e59 | 863 | loff_t ext4_llseek(struct file *file, loff_t offset, int whence) |
e0d10bfa TO |
864 | { |
865 | struct inode *inode = file->f_mapping->host; | |
866 | loff_t maxbytes; | |
867 | ||
868 | if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) | |
869 | maxbytes = EXT4_SB(inode->i_sb)->s_bitmap_maxbytes; | |
870 | else | |
871 | maxbytes = inode->i_sb->s_maxbytes; | |
e0d10bfa | 872 | |
965c8e59 | 873 | switch (whence) { |
545052e9 | 874 | default: |
965c8e59 | 875 | return generic_file_llseek_size(file, offset, whence, |
c8c0df24 | 876 | maxbytes, i_size_read(inode)); |
c8c0df24 | 877 | case SEEK_HOLE: |
545052e9 | 878 | inode_lock_shared(inode); |
09edf4d3 MB |
879 | offset = iomap_seek_hole(inode, offset, |
880 | &ext4_iomap_report_ops); | |
545052e9 CH |
881 | inode_unlock_shared(inode); |
882 | break; | |
883 | case SEEK_DATA: | |
884 | inode_lock_shared(inode); | |
09edf4d3 MB |
885 | offset = iomap_seek_data(inode, offset, |
886 | &ext4_iomap_report_ops); | |
545052e9 CH |
887 | inode_unlock_shared(inode); |
888 | break; | |
c8c0df24 ZL |
889 | } |
890 | ||
545052e9 CH |
891 | if (offset < 0) |
892 | return offset; | |
893 | return vfs_setpos(file, offset, maxbytes); | |
e0d10bfa TO |
894 | } |
895 | ||
617ba13b | 896 | const struct file_operations ext4_file_operations = { |
e0d10bfa | 897 | .llseek = ext4_llseek, |
364443cb | 898 | .read_iter = ext4_file_read_iter, |
9b884164 | 899 | .write_iter = ext4_file_write_iter, |
72f9da1d | 900 | .iopoll = iomap_dio_iopoll, |
5cdd7b2d | 901 | .unlocked_ioctl = ext4_ioctl, |
ac27a0ec | 902 | #ifdef CONFIG_COMPAT |
617ba13b | 903 | .compat_ioctl = ext4_compat_ioctl, |
ac27a0ec | 904 | #endif |
2e9ee850 | 905 | .mmap = ext4_file_mmap, |
b8a6176c | 906 | .mmap_supported_flags = MAP_SYNC, |
bc0b0d6d | 907 | .open = ext4_file_open, |
617ba13b MC |
908 | .release = ext4_release_file, |
909 | .fsync = ext4_sync_file, | |
dbe6ec81 | 910 | .get_unmapped_area = thp_get_unmapped_area, |
ac27a0ec | 911 | .splice_read = generic_file_splice_read, |
8d020765 | 912 | .splice_write = iter_file_splice_write, |
2fe17c10 | 913 | .fallocate = ext4_fallocate, |
ac27a0ec DK |
914 | }; |
915 | ||
754661f1 | 916 | const struct inode_operations ext4_file_inode_operations = { |
617ba13b | 917 | .setattr = ext4_setattr, |
99652ea5 | 918 | .getattr = ext4_file_getattr, |
617ba13b | 919 | .listxattr = ext4_listxattr, |
4e34e719 | 920 | .get_acl = ext4_get_acl, |
64e178a7 | 921 | .set_acl = ext4_set_acl, |
6873fa0d | 922 | .fiemap = ext4_fiemap, |
ac27a0ec DK |
923 | }; |
924 |