1 /*
2 * linux/fs/ext4/file.c
3 *
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
8 *
9 * from
10 *
11 * linux/fs/minix/file.c
12 *
13 * Copyright (C) 1991, 1992 Linus Torvalds
14 *
15 * ext4 fs regular file handling primitives
16 *
17 * 64-bit file support on 64-bit platforms by Jakub Jelinek
18 * (jj@sunsite.ms.mff.cuni.cz)
19 */
20
21 #include <linux/time.h>
22 #include <linux/fs.h>
23 #include <linux/mount.h>
24 #include <linux/path.h>
25 #include <linux/dax.h>
26 #include <linux/quotaops.h>
27 #include <linux/pagevec.h>
28 #include <linux/uio.h>
29 #include "ext4.h"
30 #include "ext4_jbd2.h"
31 #include "xattr.h"
32 #include "acl.h"
33
34 /*
35 * Called when an inode is released. Note that this is different
36 * from ext4_file_open: open gets called at every open, but release
37 * gets called only when /all/ the files are closed.
38 */
39 static int ext4_release_file(struct inode *inode, struct file *filp)
40 {
41 if (ext4_test_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE)) {
42 ext4_alloc_da_blocks(inode);
43 ext4_clear_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE);
44 }
45 /* if we are the last writer on the inode, drop the block reservation */
46 if ((filp->f_mode & FMODE_WRITE) &&
47 (atomic_read(&inode->i_writecount) == 1) &&
48 !EXT4_I(inode)->i_reserved_data_blocks)
49 {
50 down_write(&EXT4_I(inode)->i_data_sem);
51 ext4_discard_preallocations(inode);
52 up_write(&EXT4_I(inode)->i_data_sem);
53 }
54 if (is_dx(inode) && filp->private_data)
55 ext4_htree_free_dir_info(filp->private_data);
56
57 return 0;
58 }
59
60 static void ext4_unwritten_wait(struct inode *inode)
61 {
62 wait_queue_head_t *wq = ext4_ioend_wq(inode);
63
64 wait_event(*wq, (atomic_read(&EXT4_I(inode)->i_unwritten) == 0));
65 }
66
67 /*
68 * This tests whether the IO in question is block-aligned or not.
69 * Ext4 utilizes unwritten extents when hole-filling during direct IO, and they
70 * are converted to written only after the IO is complete. Until they are
71 * mapped, these blocks appear as holes, so dio_zero_block() will assume that
72 * it needs to zero out portions of the start and/or end block. If 2 AIO
73 * threads are at work on the same unwritten block, they must be synchronized
74 * or one thread will zero the other's data, causing corruption.
75 */
76 static int
77 ext4_unaligned_aio(struct inode *inode, struct iov_iter *from, loff_t pos)
78 {
79 struct super_block *sb = inode->i_sb;
80 int blockmask = sb->s_blocksize - 1;
81
82 if (pos >= ALIGN(i_size_read(inode), sb->s_blocksize))
83 return 0;
84
85 if ((pos | iov_iter_alignment(from)) & blockmask)
86 return 1;
87
88 return 0;
89 }
90
91 static ssize_t
92 ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
93 {
94 struct file *file = iocb->ki_filp;
95 struct inode *inode = file_inode(iocb->ki_filp);
96 struct mutex *aio_mutex = NULL;
97 struct blk_plug plug;
98 int o_direct = iocb->ki_flags & IOCB_DIRECT;
99 int overwrite = 0;
100 ssize_t ret;
101
102 /*
103 * Unaligned direct AIO must be serialized; see comment above
104 * In the case of O_APPEND, assume that we must always serialize
105 */
106 if (o_direct &&
107 ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) &&
108 !is_sync_kiocb(iocb) &&
109 (iocb->ki_flags & IOCB_APPEND ||
110 ext4_unaligned_aio(inode, from, iocb->ki_pos))) {
111 aio_mutex = ext4_aio_mutex(inode);
112 mutex_lock(aio_mutex);
113 ext4_unwritten_wait(inode);
114 }
115
116 mutex_lock(&inode->i_mutex);
117 ret = generic_write_checks(iocb, from);
118 if (ret <= 0)
119 goto out;
120
121 /*
122 * If we have encountered a bitmap-format file, the size limit
123 * is smaller than s_maxbytes, which is for extent-mapped files.
124 */
125 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
126 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
127
128 if (iocb->ki_pos >= sbi->s_bitmap_maxbytes) {
129 ret = -EFBIG;
130 goto out;
131 }
132 iov_iter_truncate(from, sbi->s_bitmap_maxbytes - iocb->ki_pos);
133 }
134
135 iocb->private = &overwrite;
136 if (o_direct) {
137 size_t length = iov_iter_count(from);
138 loff_t pos = iocb->ki_pos;
139 blk_start_plug(&plug);
140
141 /* check whether we do a DIO overwrite or not */
142 if (ext4_should_dioread_nolock(inode) && !aio_mutex &&
143 !file->f_mapping->nrpages && pos + length <= i_size_read(inode)) {
144 struct ext4_map_blocks map;
145 unsigned int blkbits = inode->i_blkbits;
146 int err, len;
147
148 map.m_lblk = pos >> blkbits;
149 map.m_len = (EXT4_BLOCK_ALIGN(pos + length, blkbits) >> blkbits)
150 - map.m_lblk;
151 len = map.m_len;
152
153 err = ext4_map_blocks(NULL, inode, &map, 0);
154 /*
155 * 'err==len' means that all of blocks has
156 * been preallocated no matter they are
157 * initialized or not. For excluding
158 * unwritten extents, we need to check
159 * m_flags. There are two conditions that
160 * indicate for initialized extents. 1) If we
161 * hit extent cache, EXT4_MAP_MAPPED flag is
162 * returned; 2) If we do a real lookup,
163 * non-flags are returned. So we should check
164 * these two conditions.
165 */
166 if (err == len && (map.m_flags & EXT4_MAP_MAPPED))
167 overwrite = 1;
168 }
169 }
170
171 ret = __generic_file_write_iter(iocb, from);
172 mutex_unlock(&inode->i_mutex);
173
174 if (ret > 0) {
175 ssize_t err;
176
177 err = generic_write_sync(file, iocb->ki_pos - ret, ret);
178 if (err < 0)
179 ret = err;
180 }
181 if (o_direct)
182 blk_finish_plug(&plug);
183
184 if (aio_mutex)
185 mutex_unlock(aio_mutex);
186 return ret;
187
188 out:
189 mutex_unlock(&inode->i_mutex);
190 if (aio_mutex)
191 mutex_unlock(aio_mutex);
192 return ret;
193 }
194
195 #ifdef CONFIG_FS_DAX
196 static void ext4_end_io_unwritten(struct buffer_head *bh, int uptodate)
197 {
198 struct inode *inode = bh->b_assoc_map->host;
199 /* XXX: breaks on 32-bit > 16TB. Is that even supported? */
200 loff_t offset = (loff_t)(uintptr_t)bh->b_private << inode->i_blkbits;
201 int err;
202 if (!uptodate)
203 return;
204 WARN_ON(!buffer_unwritten(bh));
205 err = ext4_convert_unwritten_extents(NULL, inode, offset, bh->b_size);
206 }
207
208 static int ext4_dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
209 {
210 int result;
211 handle_t *handle = NULL;
212 struct inode *inode = file_inode(vma->vm_file);
213 struct super_block *sb = inode->i_sb;
214 bool write = vmf->flags & FAULT_FLAG_WRITE;
215
216 if (write) {
217 sb_start_pagefault(sb);
218 file_update_time(vma->vm_file);
219 down_read(&EXT4_I(inode)->i_mmap_sem);
220 handle = ext4_journal_start_sb(sb, EXT4_HT_WRITE_PAGE,
221 EXT4_DATA_TRANS_BLOCKS(sb));
222 } else
223 down_read(&EXT4_I(inode)->i_mmap_sem);
224
225 if (IS_ERR(handle))
226 result = VM_FAULT_SIGBUS;
227 else
228 result = __dax_fault(vma, vmf, ext4_get_block_dax,
229 ext4_end_io_unwritten);
230
231 if (write) {
232 if (!IS_ERR(handle))
233 ext4_journal_stop(handle);
234 up_read(&EXT4_I(inode)->i_mmap_sem);
235 sb_end_pagefault(sb);
236 } else
237 up_read(&EXT4_I(inode)->i_mmap_sem);
238
239 return result;
240 }
241
242 static int ext4_dax_pmd_fault(struct vm_area_struct *vma, unsigned long addr,
243 pmd_t *pmd, unsigned int flags)
244 {
245 int result;
246 handle_t *handle = NULL;
247 struct inode *inode = file_inode(vma->vm_file);
248 struct super_block *sb = inode->i_sb;
249 bool write = flags & FAULT_FLAG_WRITE;
250
251 if (write) {
252 sb_start_pagefault(sb);
253 file_update_time(vma->vm_file);
254 down_read(&EXT4_I(inode)->i_mmap_sem);
255 handle = ext4_journal_start_sb(sb, EXT4_HT_WRITE_PAGE,
256 ext4_chunk_trans_blocks(inode,
257 PMD_SIZE / PAGE_SIZE));
258 } else
259 down_read(&EXT4_I(inode)->i_mmap_sem);
260
261 if (IS_ERR(handle))
262 result = VM_FAULT_SIGBUS;
263 else
264 result = __dax_pmd_fault(vma, addr, pmd, flags,
265 ext4_get_block_dax, ext4_end_io_unwritten);
266
267 if (write) {
268 if (!IS_ERR(handle))
269 ext4_journal_stop(handle);
270 up_read(&EXT4_I(inode)->i_mmap_sem);
271 sb_end_pagefault(sb);
272 } else
273 up_read(&EXT4_I(inode)->i_mmap_sem);
274
275 return result;
276 }
277
278 static int ext4_dax_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
279 {
280 int err;
281 struct inode *inode = file_inode(vma->vm_file);
282
283 sb_start_pagefault(inode->i_sb);
284 file_update_time(vma->vm_file);
285 down_read(&EXT4_I(inode)->i_mmap_sem);
286 err = __dax_mkwrite(vma, vmf, ext4_get_block_dax,
287 ext4_end_io_unwritten);
288 up_read(&EXT4_I(inode)->i_mmap_sem);
289 sb_end_pagefault(inode->i_sb);
290
291 return err;
292 }
293
294 /*
295 * Handle write fault for VM_MIXEDMAP mappings. Similarly to ext4_dax_mkwrite()
296 * handler we check for races agaist truncate. Note that since we cycle through
297 * i_mmap_sem, we are sure that also any hole punching that began before we
298 * were called is finished by now and so if it included part of the file we
299 * are working on, our pte will get unmapped and the check for pte_same() in
300 * wp_pfn_shared() fails. Thus fault gets retried and things work out as
301 * desired.
302 */
303 static int ext4_dax_pfn_mkwrite(struct vm_area_struct *vma,
304 struct vm_fault *vmf)
305 {
306 struct inode *inode = file_inode(vma->vm_file);
307 struct super_block *sb = inode->i_sb;
308 int ret = VM_FAULT_NOPAGE;
309 loff_t size;
310
311 sb_start_pagefault(sb);
312 file_update_time(vma->vm_file);
313 down_read(&EXT4_I(inode)->i_mmap_sem);
314 size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT;
315 if (vmf->pgoff >= size)
316 ret = VM_FAULT_SIGBUS;
317 up_read(&EXT4_I(inode)->i_mmap_sem);
318 sb_end_pagefault(sb);
319
320 return ret;
321 }
322
323 static const struct vm_operations_struct ext4_dax_vm_ops = {
324 .fault = ext4_dax_fault,
325 .pmd_fault = ext4_dax_pmd_fault,
326 .page_mkwrite = ext4_dax_mkwrite,
327 .pfn_mkwrite = ext4_dax_pfn_mkwrite,
328 };
329 #else
330 #define ext4_dax_vm_ops ext4_file_vm_ops
331 #endif
332
333 static const struct vm_operations_struct ext4_file_vm_ops = {
334 .fault = ext4_filemap_fault,
335 .map_pages = filemap_map_pages,
336 .page_mkwrite = ext4_page_mkwrite,
337 };
338
339 static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma)
340 {
341 struct inode *inode = file->f_mapping->host;
342
343 if (ext4_encrypted_inode(inode)) {
344 int err = ext4_get_encryption_info(inode);
345 if (err)
346 return 0;
347 if (ext4_encryption_info(inode) == NULL)
348 return -ENOKEY;
349 }
350 file_accessed(file);
351 if (IS_DAX(file_inode(file))) {
352 vma->vm_ops = &ext4_dax_vm_ops;
353 vma->vm_flags |= VM_MIXEDMAP | VM_HUGEPAGE;
354 } else {
355 vma->vm_ops = &ext4_file_vm_ops;
356 }
357 return 0;
358 }
359
360 static int ext4_file_open(struct inode * inode, struct file * filp)
361 {
362 struct super_block *sb = inode->i_sb;
363 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
364 struct vfsmount *mnt = filp->f_path.mnt;
365 struct path path;
366 char buf[64], *cp;
367 int ret;
368
369 if (unlikely(!(sbi->s_mount_flags & EXT4_MF_MNTDIR_SAMPLED) &&
370 !(sb->s_flags & MS_RDONLY))) {
371 sbi->s_mount_flags |= EXT4_MF_MNTDIR_SAMPLED;
372 /*
373 * Sample where the filesystem has been mounted and
374 * store it in the superblock for sysadmin convenience
375 * when trying to sort through large numbers of block
376 * devices or filesystem images.
377 */
378 memset(buf, 0, sizeof(buf));
379 path.mnt = mnt;
380 path.dentry = mnt->mnt_root;
381 cp = d_path(&path, buf, sizeof(buf));
382 if (!IS_ERR(cp)) {
383 handle_t *handle;
384 int err;
385
386 handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1);
387 if (IS_ERR(handle))
388 return PTR_ERR(handle);
389 BUFFER_TRACE(sbi->s_sbh, "get_write_access");
390 err = ext4_journal_get_write_access(handle, sbi->s_sbh);
391 if (err) {
392 ext4_journal_stop(handle);
393 return err;
394 }
395 strlcpy(sbi->s_es->s_last_mounted, cp,
396 sizeof(sbi->s_es->s_last_mounted));
397 ext4_handle_dirty_super(handle, sb);
398 ext4_journal_stop(handle);
399 }
400 }
401 if (ext4_encrypted_inode(inode)) {
402 ret = ext4_get_encryption_info(inode);
403 if (ret)
404 return -EACCES;
405 if (ext4_encryption_info(inode) == NULL)
406 return -ENOKEY;
407 }
408 /*
409 * Set up the jbd2_inode if we are opening the inode for
410 * writing and the journal is present
411 */
412 if (filp->f_mode & FMODE_WRITE) {
413 ret = ext4_inode_attach_jinode(inode);
414 if (ret < 0)
415 return ret;
416 }
417 return dquot_file_open(inode, filp);
418 }
419
420 /*
421 * Here we use ext4_map_blocks() to get a block mapping for a extent-based
422 * file rather than ext4_ext_walk_space() because we can introduce
423 * SEEK_DATA/SEEK_HOLE for block-mapped and extent-mapped file at the same
424 * function. When extent status tree has been fully implemented, it will
425 * track all extent status for a file and we can directly use it to
426 * retrieve the offset for SEEK_DATA/SEEK_HOLE.
427 */
428
429 /*
430 * When we retrieve the offset for SEEK_DATA/SEEK_HOLE, we would need to
431 * lookup page cache to check whether or not there has some data between
432 * [startoff, endoff] because, if this range contains an unwritten extent,
433 * we determine this extent as a data or a hole according to whether the
434 * page cache has data or not.
435 */
436 static int ext4_find_unwritten_pgoff(struct inode *inode,
437 int whence,
438 struct ext4_map_blocks *map,
439 loff_t *offset)
440 {
441 struct pagevec pvec;
442 unsigned int blkbits;
443 pgoff_t index;
444 pgoff_t end;
445 loff_t endoff;
446 loff_t startoff;
447 loff_t lastoff;
448 int found = 0;
449
450 blkbits = inode->i_sb->s_blocksize_bits;
451 startoff = *offset;
452 lastoff = startoff;
453 endoff = (loff_t)(map->m_lblk + map->m_len) << blkbits;
454
455 index = startoff >> PAGE_CACHE_SHIFT;
456 end = endoff >> PAGE_CACHE_SHIFT;
457
458 pagevec_init(&pvec, 0);
459 do {
460 int i, num;
461 unsigned long nr_pages;
462
463 num = min_t(pgoff_t, end - index, PAGEVEC_SIZE - 1) + 1;
464 nr_pages = pagevec_lookup(&pvec, inode->i_mapping, index,
465 (pgoff_t)num);
466 if (nr_pages == 0)
467 break;
468
469 for (i = 0; i < nr_pages; i++) {
470 struct page *page = pvec.pages[i];
471 struct buffer_head *bh, *head;
472
473 /*
474 * If current offset is smaller than the page offset,
475 * there is a hole at this offset.
476 */
477 if (whence == SEEK_HOLE && lastoff < endoff &&
478 lastoff < page_offset(pvec.pages[i])) {
479 found = 1;
480 *offset = lastoff;
481 goto out;
482 }
483
484 if (page->index > end)
485 goto out;
486
487 lock_page(page);
488
489 if (unlikely(page->mapping != inode->i_mapping)) {
490 unlock_page(page);
491 continue;
492 }
493
494 if (!page_has_buffers(page)) {
495 unlock_page(page);
496 continue;
497 }
498
499 if (page_has_buffers(page)) {
500 lastoff = page_offset(page);
501 bh = head = page_buffers(page);
502 do {
503 if (lastoff + bh->b_size <= startoff)
504 goto next;
505 if (buffer_uptodate(bh) ||
506 buffer_unwritten(bh)) {
507 if (whence == SEEK_DATA)
508 found = 1;
509 } else {
510 if (whence == SEEK_HOLE)
511 found = 1;
512 }
513 if (found) {
514 *offset = max_t(loff_t,
515 startoff, lastoff);
516 unlock_page(page);
517 goto out;
518 }
519 next:
520 lastoff += bh->b_size;
521 bh = bh->b_this_page;
522 } while (bh != head);
523 }
524
525 lastoff = page_offset(page) + PAGE_SIZE;
526 unlock_page(page);
527 }
528
529 /* The no. of pages is less than our desired, we are done. */
530 if (nr_pages < num)
531 break;
532
533 index = pvec.pages[i - 1]->index + 1;
534 pagevec_release(&pvec);
535 } while (index <= end);
536
537 if (whence == SEEK_HOLE && lastoff < endoff) {
538 found = 1;
539 *offset = lastoff;
540 }
541 out:
542 pagevec_release(&pvec);
543 return found;
544 }
545
546 /*
547 * ext4_seek_data() retrieves the offset for SEEK_DATA.
548 */
549 static loff_t ext4_seek_data(struct file *file, loff_t offset, loff_t maxsize)
550 {
551 struct inode *inode = file->f_mapping->host;
552 struct ext4_map_blocks map;
553 struct extent_status es;
554 ext4_lblk_t start, last, end;
555 loff_t dataoff, isize;
556 int blkbits;
557 int ret = 0;
558
559 mutex_lock(&inode->i_mutex);
560
561 isize = i_size_read(inode);
562 if (offset < 0 || offset >= isize) {
563 mutex_unlock(&inode->i_mutex);
564 return -ENXIO;
565 }
566
567 blkbits = inode->i_sb->s_blocksize_bits;
568 start = offset >> blkbits;
569 last = start;
570 end = isize >> blkbits;
571 dataoff = offset;
572
573 do {
574 map.m_lblk = last;
575 map.m_len = end - last + 1;
576 ret = ext4_map_blocks(NULL, inode, &map, 0);
577 if (ret > 0 && !(map.m_flags & EXT4_MAP_UNWRITTEN)) {
578 if (last != start)
579 dataoff = (loff_t)last << blkbits;
580 break;
581 }
582
583 /*
584 * If there is a delay extent at this offset,
585 * it will be as a data.
586 */
587 ext4_es_find_delayed_extent_range(inode, last, last, &es);
588 if (es.es_len != 0 && in_range(last, es.es_lblk, es.es_len)) {
589 if (last != start)
590 dataoff = (loff_t)last << blkbits;
591 break;
592 }
593
594 /*
595 * If there is a unwritten extent at this offset,
596 * it will be as a data or a hole according to page
597 * cache that has data or not.
598 */
599 if (map.m_flags & EXT4_MAP_UNWRITTEN) {
600 int unwritten;
601 unwritten = ext4_find_unwritten_pgoff(inode, SEEK_DATA,
602 &map, &dataoff);
603 if (unwritten)
604 break;
605 }
606
607 last++;
608 dataoff = (loff_t)last << blkbits;
609 } while (last <= end);
610
611 mutex_unlock(&inode->i_mutex);
612
613 if (dataoff > isize)
614 return -ENXIO;
615
616 return vfs_setpos(file, dataoff, maxsize);
617 }
618
619 /*
620 * ext4_seek_hole() retrieves the offset for SEEK_HOLE.
621 */
622 static loff_t ext4_seek_hole(struct file *file, loff_t offset, loff_t maxsize)
623 {
624 struct inode *inode = file->f_mapping->host;
625 struct ext4_map_blocks map;
626 struct extent_status es;
627 ext4_lblk_t start, last, end;
628 loff_t holeoff, isize;
629 int blkbits;
630 int ret = 0;
631
632 mutex_lock(&inode->i_mutex);
633
634 isize = i_size_read(inode);
635 if (offset < 0 || offset >= isize) {
636 mutex_unlock(&inode->i_mutex);
637 return -ENXIO;
638 }
639
640 blkbits = inode->i_sb->s_blocksize_bits;
641 start = offset >> blkbits;
642 last = start;
643 end = isize >> blkbits;
644 holeoff = offset;
645
646 do {
647 map.m_lblk = last;
648 map.m_len = end - last + 1;
649 ret = ext4_map_blocks(NULL, inode, &map, 0);
650 if (ret > 0 && !(map.m_flags & EXT4_MAP_UNWRITTEN)) {
651 last += ret;
652 holeoff = (loff_t)last << blkbits;
653 continue;
654 }
655
656 /*
657 * If there is a delay extent at this offset,
658 * we will skip this extent.
659 */
660 ext4_es_find_delayed_extent_range(inode, last, last, &es);
661 if (es.es_len != 0 && in_range(last, es.es_lblk, es.es_len)) {
662 last = es.es_lblk + es.es_len;
663 holeoff = (loff_t)last << blkbits;
664 continue;
665 }
666
667 /*
668 * If there is a unwritten extent at this offset,
669 * it will be as a data or a hole according to page
670 * cache that has data or not.
671 */
672 if (map.m_flags & EXT4_MAP_UNWRITTEN) {
673 int unwritten;
674 unwritten = ext4_find_unwritten_pgoff(inode, SEEK_HOLE,
675 &map, &holeoff);
676 if (!unwritten) {
677 last += ret;
678 holeoff = (loff_t)last << blkbits;
679 continue;
680 }
681 }
682
683 /* find a hole */
684 break;
685 } while (last <= end);
686
687 mutex_unlock(&inode->i_mutex);
688
689 if (holeoff > isize)
690 holeoff = isize;
691
692 return vfs_setpos(file, holeoff, maxsize);
693 }
694
695 /*
696 * ext4_llseek() handles both block-mapped and extent-mapped maxbytes values
697 * by calling generic_file_llseek_size() with the appropriate maxbytes
698 * value for each.
699 */
700 loff_t ext4_llseek(struct file *file, loff_t offset, int whence)
701 {
702 struct inode *inode = file->f_mapping->host;
703 loff_t maxbytes;
704
705 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
706 maxbytes = EXT4_SB(inode->i_sb)->s_bitmap_maxbytes;
707 else
708 maxbytes = inode->i_sb->s_maxbytes;
709
710 switch (whence) {
711 case SEEK_SET:
712 case SEEK_CUR:
713 case SEEK_END:
714 return generic_file_llseek_size(file, offset, whence,
715 maxbytes, i_size_read(inode));
716 case SEEK_DATA:
717 return ext4_seek_data(file, offset, maxbytes);
718 case SEEK_HOLE:
719 return ext4_seek_hole(file, offset, maxbytes);
720 }
721
722 return -EINVAL;
723 }
724
725 const struct file_operations ext4_file_operations = {
726 .llseek = ext4_llseek,
727 .read_iter = generic_file_read_iter,
728 .write_iter = ext4_file_write_iter,
729 .unlocked_ioctl = ext4_ioctl,
730 #ifdef CONFIG_COMPAT
731 .compat_ioctl = ext4_compat_ioctl,
732 #endif
733 .mmap = ext4_file_mmap,
734 .open = ext4_file_open,
735 .release = ext4_release_file,
736 .fsync = ext4_sync_file,
737 .splice_read = generic_file_splice_read,
738 .splice_write = iter_file_splice_write,
739 .fallocate = ext4_fallocate,
740 };
741
742 const struct inode_operations ext4_file_inode_operations = {
743 .setattr = ext4_setattr,
744 .getattr = ext4_getattr,
745 .setxattr = generic_setxattr,
746 .getxattr = generic_getxattr,
747 .listxattr = ext4_listxattr,
748 .removexattr = generic_removexattr,
749 .get_acl = ext4_get_acl,
750 .set_acl = ext4_set_acl,
751 .fiemap = ext4_fiemap,
752 };
753
754
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