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Merge tag 'platform-drivers-x86-v6.11-4' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-block.git] / fs / gfs2 / file.c
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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
4 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
5 */
6
7#include <linux/slab.h>
8#include <linux/spinlock.h>
9#include <linux/compat.h>
10#include <linux/completion.h>
11#include <linux/buffer_head.h>
12#include <linux/pagemap.h>
13#include <linux/uio.h>
14#include <linux/blkdev.h>
15#include <linux/mm.h>
16#include <linux/mount.h>
17#include <linux/fs.h>
18#include <linux/filelock.h>
19#include <linux/gfs2_ondisk.h>
20#include <linux/falloc.h>
21#include <linux/swap.h>
22#include <linux/crc32.h>
23#include <linux/writeback.h>
24#include <linux/uaccess.h>
25#include <linux/dlm.h>
26#include <linux/dlm_plock.h>
27#include <linux/delay.h>
28#include <linux/backing-dev.h>
29#include <linux/fileattr.h>
30
31#include "gfs2.h"
32#include "incore.h"
33#include "bmap.h"
34#include "aops.h"
35#include "dir.h"
36#include "glock.h"
37#include "glops.h"
38#include "inode.h"
39#include "log.h"
40#include "meta_io.h"
41#include "quota.h"
42#include "rgrp.h"
43#include "trans.h"
44#include "util.h"
45
46/**
47 * gfs2_llseek - seek to a location in a file
48 * @file: the file
49 * @offset: the offset
50 * @whence: Where to seek from (SEEK_SET, SEEK_CUR, or SEEK_END)
51 *
52 * SEEK_END requires the glock for the file because it references the
53 * file's size.
54 *
55 * Returns: The new offset, or errno
56 */
57
58static loff_t gfs2_llseek(struct file *file, loff_t offset, int whence)
59{
60 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
61 struct gfs2_holder i_gh;
62 loff_t error;
63
64 switch (whence) {
65 case SEEK_END:
66 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
67 &i_gh);
68 if (!error) {
69 error = generic_file_llseek(file, offset, whence);
70 gfs2_glock_dq_uninit(&i_gh);
71 }
72 break;
73
74 case SEEK_DATA:
75 error = gfs2_seek_data(file, offset);
76 break;
77
78 case SEEK_HOLE:
79 error = gfs2_seek_hole(file, offset);
80 break;
81
82 case SEEK_CUR:
83 case SEEK_SET:
84 /*
85 * These don't reference inode->i_size and don't depend on the
86 * block mapping, so we don't need the glock.
87 */
88 error = generic_file_llseek(file, offset, whence);
89 break;
90 default:
91 error = -EINVAL;
92 }
93
94 return error;
95}
96
97/**
98 * gfs2_readdir - Iterator for a directory
99 * @file: The directory to read from
100 * @ctx: What to feed directory entries to
101 *
102 * Returns: errno
103 */
104
105static int gfs2_readdir(struct file *file, struct dir_context *ctx)
106{
107 struct inode *dir = file->f_mapping->host;
108 struct gfs2_inode *dip = GFS2_I(dir);
109 struct gfs2_holder d_gh;
110 int error;
111
112 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
113 if (error)
114 return error;
115
116 error = gfs2_dir_read(dir, ctx, &file->f_ra);
117
118 gfs2_glock_dq_uninit(&d_gh);
119
120 return error;
121}
122
123/*
124 * struct fsflag_gfs2flag
125 *
126 * The FS_JOURNAL_DATA_FL flag maps to GFS2_DIF_INHERIT_JDATA for directories,
127 * and to GFS2_DIF_JDATA for non-directories.
128 */
129static struct {
130 u32 fsflag;
131 u32 gfsflag;
132} fsflag_gfs2flag[] = {
133 {FS_SYNC_FL, GFS2_DIF_SYNC},
134 {FS_IMMUTABLE_FL, GFS2_DIF_IMMUTABLE},
135 {FS_APPEND_FL, GFS2_DIF_APPENDONLY},
136 {FS_NOATIME_FL, GFS2_DIF_NOATIME},
137 {FS_INDEX_FL, GFS2_DIF_EXHASH},
138 {FS_TOPDIR_FL, GFS2_DIF_TOPDIR},
139 {FS_JOURNAL_DATA_FL, GFS2_DIF_JDATA | GFS2_DIF_INHERIT_JDATA},
140};
141
142static inline u32 gfs2_gfsflags_to_fsflags(struct inode *inode, u32 gfsflags)
143{
144 int i;
145 u32 fsflags = 0;
146
147 if (S_ISDIR(inode->i_mode))
148 gfsflags &= ~GFS2_DIF_JDATA;
149 else
150 gfsflags &= ~GFS2_DIF_INHERIT_JDATA;
151
152 for (i = 0; i < ARRAY_SIZE(fsflag_gfs2flag); i++)
153 if (gfsflags & fsflag_gfs2flag[i].gfsflag)
154 fsflags |= fsflag_gfs2flag[i].fsflag;
155 return fsflags;
156}
157
158int gfs2_fileattr_get(struct dentry *dentry, struct fileattr *fa)
159{
160 struct inode *inode = d_inode(dentry);
161 struct gfs2_inode *ip = GFS2_I(inode);
162 struct gfs2_holder gh;
163 int error;
164 u32 fsflags;
165
166 if (d_is_special(dentry))
167 return -ENOTTY;
168
169 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
170 error = gfs2_glock_nq(&gh);
171 if (error)
172 goto out_uninit;
173
174 fsflags = gfs2_gfsflags_to_fsflags(inode, ip->i_diskflags);
175
176 fileattr_fill_flags(fa, fsflags);
177
178 gfs2_glock_dq(&gh);
179out_uninit:
180 gfs2_holder_uninit(&gh);
181 return error;
182}
183
184void gfs2_set_inode_flags(struct inode *inode)
185{
186 struct gfs2_inode *ip = GFS2_I(inode);
187 unsigned int flags = inode->i_flags;
188
189 flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC|S_NOSEC);
190 if ((ip->i_eattr == 0) && !is_sxid(inode->i_mode))
191 flags |= S_NOSEC;
192 if (ip->i_diskflags & GFS2_DIF_IMMUTABLE)
193 flags |= S_IMMUTABLE;
194 if (ip->i_diskflags & GFS2_DIF_APPENDONLY)
195 flags |= S_APPEND;
196 if (ip->i_diskflags & GFS2_DIF_NOATIME)
197 flags |= S_NOATIME;
198 if (ip->i_diskflags & GFS2_DIF_SYNC)
199 flags |= S_SYNC;
200 inode->i_flags = flags;
201}
202
203/* Flags that can be set by user space */
204#define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA| \
205 GFS2_DIF_IMMUTABLE| \
206 GFS2_DIF_APPENDONLY| \
207 GFS2_DIF_NOATIME| \
208 GFS2_DIF_SYNC| \
209 GFS2_DIF_TOPDIR| \
210 GFS2_DIF_INHERIT_JDATA)
211
212/**
213 * do_gfs2_set_flags - set flags on an inode
214 * @inode: The inode
215 * @reqflags: The flags to set
216 * @mask: Indicates which flags are valid
217 *
218 */
219static int do_gfs2_set_flags(struct inode *inode, u32 reqflags, u32 mask)
220{
221 struct gfs2_inode *ip = GFS2_I(inode);
222 struct gfs2_sbd *sdp = GFS2_SB(inode);
223 struct buffer_head *bh;
224 struct gfs2_holder gh;
225 int error;
226 u32 new_flags, flags;
227
228 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
229 if (error)
230 return error;
231
232 error = 0;
233 flags = ip->i_diskflags;
234 new_flags = (flags & ~mask) | (reqflags & mask);
235 if ((new_flags ^ flags) == 0)
236 goto out;
237
238 if (!IS_IMMUTABLE(inode)) {
239 error = gfs2_permission(&nop_mnt_idmap, inode, MAY_WRITE);
240 if (error)
241 goto out;
242 }
243 if ((flags ^ new_flags) & GFS2_DIF_JDATA) {
244 if (new_flags & GFS2_DIF_JDATA)
245 gfs2_log_flush(sdp, ip->i_gl,
246 GFS2_LOG_HEAD_FLUSH_NORMAL |
247 GFS2_LFC_SET_FLAGS);
248 error = filemap_fdatawrite(inode->i_mapping);
249 if (error)
250 goto out;
251 error = filemap_fdatawait(inode->i_mapping);
252 if (error)
253 goto out;
254 if (new_flags & GFS2_DIF_JDATA)
255 gfs2_ordered_del_inode(ip);
256 }
257 error = gfs2_trans_begin(sdp, RES_DINODE, 0);
258 if (error)
259 goto out;
260 error = gfs2_meta_inode_buffer(ip, &bh);
261 if (error)
262 goto out_trans_end;
263 inode_set_ctime_current(inode);
264 gfs2_trans_add_meta(ip->i_gl, bh);
265 ip->i_diskflags = new_flags;
266 gfs2_dinode_out(ip, bh->b_data);
267 brelse(bh);
268 gfs2_set_inode_flags(inode);
269 gfs2_set_aops(inode);
270out_trans_end:
271 gfs2_trans_end(sdp);
272out:
273 gfs2_glock_dq_uninit(&gh);
274 return error;
275}
276
277int gfs2_fileattr_set(struct mnt_idmap *idmap,
278 struct dentry *dentry, struct fileattr *fa)
279{
280 struct inode *inode = d_inode(dentry);
281 u32 fsflags = fa->flags, gfsflags = 0;
282 u32 mask;
283 int i;
284
285 if (d_is_special(dentry))
286 return -ENOTTY;
287
288 if (fileattr_has_fsx(fa))
289 return -EOPNOTSUPP;
290
291 for (i = 0; i < ARRAY_SIZE(fsflag_gfs2flag); i++) {
292 if (fsflags & fsflag_gfs2flag[i].fsflag) {
293 fsflags &= ~fsflag_gfs2flag[i].fsflag;
294 gfsflags |= fsflag_gfs2flag[i].gfsflag;
295 }
296 }
297 if (fsflags || gfsflags & ~GFS2_FLAGS_USER_SET)
298 return -EINVAL;
299
300 mask = GFS2_FLAGS_USER_SET;
301 if (S_ISDIR(inode->i_mode)) {
302 mask &= ~GFS2_DIF_JDATA;
303 } else {
304 /* The GFS2_DIF_TOPDIR flag is only valid for directories. */
305 if (gfsflags & GFS2_DIF_TOPDIR)
306 return -EINVAL;
307 mask &= ~(GFS2_DIF_TOPDIR | GFS2_DIF_INHERIT_JDATA);
308 }
309
310 return do_gfs2_set_flags(inode, gfsflags, mask);
311}
312
313static int gfs2_getlabel(struct file *filp, char __user *label)
314{
315 struct inode *inode = file_inode(filp);
316 struct gfs2_sbd *sdp = GFS2_SB(inode);
317
318 if (copy_to_user(label, sdp->sd_sb.sb_locktable, GFS2_LOCKNAME_LEN))
319 return -EFAULT;
320
321 return 0;
322}
323
324static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
325{
326 switch(cmd) {
327 case FITRIM:
328 return gfs2_fitrim(filp, (void __user *)arg);
329 case FS_IOC_GETFSLABEL:
330 return gfs2_getlabel(filp, (char __user *)arg);
331 }
332
333 return -ENOTTY;
334}
335
336#ifdef CONFIG_COMPAT
337static long gfs2_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
338{
339 switch(cmd) {
340 /* Keep this list in sync with gfs2_ioctl */
341 case FITRIM:
342 case FS_IOC_GETFSLABEL:
343 break;
344 default:
345 return -ENOIOCTLCMD;
346 }
347
348 return gfs2_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
349}
350#else
351#define gfs2_compat_ioctl NULL
352#endif
353
354/**
355 * gfs2_size_hint - Give a hint to the size of a write request
356 * @filep: The struct file
357 * @offset: The file offset of the write
358 * @size: The length of the write
359 *
360 * When we are about to do a write, this function records the total
361 * write size in order to provide a suitable hint to the lower layers
362 * about how many blocks will be required.
363 *
364 */
365
366static void gfs2_size_hint(struct file *filep, loff_t offset, size_t size)
367{
368 struct inode *inode = file_inode(filep);
369 struct gfs2_sbd *sdp = GFS2_SB(inode);
370 struct gfs2_inode *ip = GFS2_I(inode);
371 size_t blks = (size + sdp->sd_sb.sb_bsize - 1) >> sdp->sd_sb.sb_bsize_shift;
372 int hint = min_t(size_t, INT_MAX, blks);
373
374 if (hint > atomic_read(&ip->i_sizehint))
375 atomic_set(&ip->i_sizehint, hint);
376}
377
378/**
379 * gfs2_allocate_folio_backing - Allocate blocks for a write fault
380 * @folio: The (locked) folio to allocate backing for
381 * @length: Size of the allocation
382 *
383 * We try to allocate all the blocks required for the folio in one go. This
384 * might fail for various reasons, so we keep trying until all the blocks to
385 * back this folio are allocated. If some of the blocks are already allocated,
386 * that is ok too.
387 */
388static int gfs2_allocate_folio_backing(struct folio *folio, size_t length)
389{
390 u64 pos = folio_pos(folio);
391
392 do {
393 struct iomap iomap = { };
394
395 if (gfs2_iomap_alloc(folio->mapping->host, pos, length, &iomap))
396 return -EIO;
397
398 if (length < iomap.length)
399 iomap.length = length;
400 length -= iomap.length;
401 pos += iomap.length;
402 } while (length > 0);
403
404 return 0;
405}
406
407/**
408 * gfs2_page_mkwrite - Make a shared, mmap()ed, page writable
409 * @vmf: The virtual memory fault containing the page to become writable
410 *
411 * When the page becomes writable, we need to ensure that we have
412 * blocks allocated on disk to back that page.
413 */
414
415static vm_fault_t gfs2_page_mkwrite(struct vm_fault *vmf)
416{
417 struct folio *folio = page_folio(vmf->page);
418 struct inode *inode = file_inode(vmf->vma->vm_file);
419 struct gfs2_inode *ip = GFS2_I(inode);
420 struct gfs2_sbd *sdp = GFS2_SB(inode);
421 struct gfs2_alloc_parms ap = {};
422 u64 pos = folio_pos(folio);
423 unsigned int data_blocks, ind_blocks, rblocks;
424 vm_fault_t ret = VM_FAULT_LOCKED;
425 struct gfs2_holder gh;
426 size_t length;
427 loff_t size;
428 int err;
429
430 sb_start_pagefault(inode->i_sb);
431
432 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
433 err = gfs2_glock_nq(&gh);
434 if (err) {
435 ret = vmf_fs_error(err);
436 goto out_uninit;
437 }
438
439 /* Check folio index against inode size */
440 size = i_size_read(inode);
441 if (pos >= size) {
442 ret = VM_FAULT_SIGBUS;
443 goto out_unlock;
444 }
445
446 /* Update file times before taking folio lock */
447 file_update_time(vmf->vma->vm_file);
448
449 /* folio is wholly or partially inside EOF */
450 if (size - pos < folio_size(folio))
451 length = size - pos;
452 else
453 length = folio_size(folio);
454
455 gfs2_size_hint(vmf->vma->vm_file, pos, length);
456
457 set_bit(GLF_DIRTY, &ip->i_gl->gl_flags);
458 set_bit(GIF_SW_PAGED, &ip->i_flags);
459
460 /*
461 * iomap_writepage / iomap_writepages currently don't support inline
462 * files, so always unstuff here.
463 */
464
465 if (!gfs2_is_stuffed(ip) &&
466 !gfs2_write_alloc_required(ip, pos, length)) {
467 folio_lock(folio);
468 if (!folio_test_uptodate(folio) ||
469 folio->mapping != inode->i_mapping) {
470 ret = VM_FAULT_NOPAGE;
471 folio_unlock(folio);
472 }
473 goto out_unlock;
474 }
475
476 err = gfs2_rindex_update(sdp);
477 if (err) {
478 ret = vmf_fs_error(err);
479 goto out_unlock;
480 }
481
482 gfs2_write_calc_reserv(ip, length, &data_blocks, &ind_blocks);
483 ap.target = data_blocks + ind_blocks;
484 err = gfs2_quota_lock_check(ip, &ap);
485 if (err) {
486 ret = vmf_fs_error(err);
487 goto out_unlock;
488 }
489 err = gfs2_inplace_reserve(ip, &ap);
490 if (err) {
491 ret = vmf_fs_error(err);
492 goto out_quota_unlock;
493 }
494
495 rblocks = RES_DINODE + ind_blocks;
496 if (gfs2_is_jdata(ip))
497 rblocks += data_blocks ? data_blocks : 1;
498 if (ind_blocks || data_blocks) {
499 rblocks += RES_STATFS + RES_QUOTA;
500 rblocks += gfs2_rg_blocks(ip, data_blocks + ind_blocks);
501 }
502 err = gfs2_trans_begin(sdp, rblocks, 0);
503 if (err) {
504 ret = vmf_fs_error(err);
505 goto out_trans_fail;
506 }
507
508 /* Unstuff, if required, and allocate backing blocks for folio */
509 if (gfs2_is_stuffed(ip)) {
510 err = gfs2_unstuff_dinode(ip);
511 if (err) {
512 ret = vmf_fs_error(err);
513 goto out_trans_end;
514 }
515 }
516
517 folio_lock(folio);
518 /* If truncated, we must retry the operation, we may have raced
519 * with the glock demotion code.
520 */
521 if (!folio_test_uptodate(folio) || folio->mapping != inode->i_mapping) {
522 ret = VM_FAULT_NOPAGE;
523 goto out_page_locked;
524 }
525
526 err = gfs2_allocate_folio_backing(folio, length);
527 if (err)
528 ret = vmf_fs_error(err);
529
530out_page_locked:
531 if (ret != VM_FAULT_LOCKED)
532 folio_unlock(folio);
533out_trans_end:
534 gfs2_trans_end(sdp);
535out_trans_fail:
536 gfs2_inplace_release(ip);
537out_quota_unlock:
538 gfs2_quota_unlock(ip);
539out_unlock:
540 gfs2_glock_dq(&gh);
541out_uninit:
542 gfs2_holder_uninit(&gh);
543 if (ret == VM_FAULT_LOCKED) {
544 folio_mark_dirty(folio);
545 folio_wait_stable(folio);
546 }
547 sb_end_pagefault(inode->i_sb);
548 return ret;
549}
550
551static vm_fault_t gfs2_fault(struct vm_fault *vmf)
552{
553 struct inode *inode = file_inode(vmf->vma->vm_file);
554 struct gfs2_inode *ip = GFS2_I(inode);
555 struct gfs2_holder gh;
556 vm_fault_t ret;
557 int err;
558
559 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
560 err = gfs2_glock_nq(&gh);
561 if (err) {
562 ret = vmf_fs_error(err);
563 goto out_uninit;
564 }
565 ret = filemap_fault(vmf);
566 gfs2_glock_dq(&gh);
567out_uninit:
568 gfs2_holder_uninit(&gh);
569 return ret;
570}
571
572static const struct vm_operations_struct gfs2_vm_ops = {
573 .fault = gfs2_fault,
574 .map_pages = filemap_map_pages,
575 .page_mkwrite = gfs2_page_mkwrite,
576};
577
578/**
579 * gfs2_mmap
580 * @file: The file to map
581 * @vma: The VMA which described the mapping
582 *
583 * There is no need to get a lock here unless we should be updating
584 * atime. We ignore any locking errors since the only consequence is
585 * a missed atime update (which will just be deferred until later).
586 *
587 * Returns: 0
588 */
589
590static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
591{
592 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
593
594 if (!(file->f_flags & O_NOATIME) &&
595 !IS_NOATIME(&ip->i_inode)) {
596 struct gfs2_holder i_gh;
597 int error;
598
599 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
600 &i_gh);
601 if (error)
602 return error;
603 /* grab lock to update inode */
604 gfs2_glock_dq_uninit(&i_gh);
605 file_accessed(file);
606 }
607 vma->vm_ops = &gfs2_vm_ops;
608
609 return 0;
610}
611
612/**
613 * gfs2_open_common - This is common to open and atomic_open
614 * @inode: The inode being opened
615 * @file: The file being opened
616 *
617 * This maybe called under a glock or not depending upon how it has
618 * been called. We must always be called under a glock for regular
619 * files, however. For other file types, it does not matter whether
620 * we hold the glock or not.
621 *
622 * Returns: Error code or 0 for success
623 */
624
625int gfs2_open_common(struct inode *inode, struct file *file)
626{
627 struct gfs2_file *fp;
628 int ret;
629
630 if (S_ISREG(inode->i_mode)) {
631 ret = generic_file_open(inode, file);
632 if (ret)
633 return ret;
634
635 if (!gfs2_is_jdata(GFS2_I(inode)))
636 file->f_mode |= FMODE_CAN_ODIRECT;
637 }
638
639 fp = kzalloc(sizeof(struct gfs2_file), GFP_NOFS);
640 if (!fp)
641 return -ENOMEM;
642
643 mutex_init(&fp->f_fl_mutex);
644
645 gfs2_assert_warn(GFS2_SB(inode), !file->private_data);
646 file->private_data = fp;
647 if (file->f_mode & FMODE_WRITE) {
648 ret = gfs2_qa_get(GFS2_I(inode));
649 if (ret)
650 goto fail;
651 }
652 return 0;
653
654fail:
655 kfree(file->private_data);
656 file->private_data = NULL;
657 return ret;
658}
659
660/**
661 * gfs2_open - open a file
662 * @inode: the inode to open
663 * @file: the struct file for this opening
664 *
665 * After atomic_open, this function is only used for opening files
666 * which are already cached. We must still get the glock for regular
667 * files to ensure that we have the file size uptodate for the large
668 * file check which is in the common code. That is only an issue for
669 * regular files though.
670 *
671 * Returns: errno
672 */
673
674static int gfs2_open(struct inode *inode, struct file *file)
675{
676 struct gfs2_inode *ip = GFS2_I(inode);
677 struct gfs2_holder i_gh;
678 int error;
679 bool need_unlock = false;
680
681 if (S_ISREG(ip->i_inode.i_mode)) {
682 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
683 &i_gh);
684 if (error)
685 return error;
686 need_unlock = true;
687 }
688
689 error = gfs2_open_common(inode, file);
690
691 if (need_unlock)
692 gfs2_glock_dq_uninit(&i_gh);
693
694 return error;
695}
696
697/**
698 * gfs2_release - called to close a struct file
699 * @inode: the inode the struct file belongs to
700 * @file: the struct file being closed
701 *
702 * Returns: errno
703 */
704
705static int gfs2_release(struct inode *inode, struct file *file)
706{
707 struct gfs2_inode *ip = GFS2_I(inode);
708
709 kfree(file->private_data);
710 file->private_data = NULL;
711
712 if (file->f_mode & FMODE_WRITE) {
713 if (gfs2_rs_active(&ip->i_res))
714 gfs2_rs_delete(ip);
715 gfs2_qa_put(ip);
716 }
717 return 0;
718}
719
720/**
721 * gfs2_fsync - sync the dirty data for a file (across the cluster)
722 * @file: the file that points to the dentry
723 * @start: the start position in the file to sync
724 * @end: the end position in the file to sync
725 * @datasync: set if we can ignore timestamp changes
726 *
727 * We split the data flushing here so that we don't wait for the data
728 * until after we've also sent the metadata to disk. Note that for
729 * data=ordered, we will write & wait for the data at the log flush
730 * stage anyway, so this is unlikely to make much of a difference
731 * except in the data=writeback case.
732 *
733 * If the fdatawrite fails due to any reason except -EIO, we will
734 * continue the remainder of the fsync, although we'll still report
735 * the error at the end. This is to match filemap_write_and_wait_range()
736 * behaviour.
737 *
738 * Returns: errno
739 */
740
741static int gfs2_fsync(struct file *file, loff_t start, loff_t end,
742 int datasync)
743{
744 struct address_space *mapping = file->f_mapping;
745 struct inode *inode = mapping->host;
746 int sync_state = inode->i_state & I_DIRTY;
747 struct gfs2_inode *ip = GFS2_I(inode);
748 int ret = 0, ret1 = 0;
749
750 if (mapping->nrpages) {
751 ret1 = filemap_fdatawrite_range(mapping, start, end);
752 if (ret1 == -EIO)
753 return ret1;
754 }
755
756 if (!gfs2_is_jdata(ip))
757 sync_state &= ~I_DIRTY_PAGES;
758 if (datasync)
759 sync_state &= ~I_DIRTY_SYNC;
760
761 if (sync_state) {
762 ret = sync_inode_metadata(inode, 1);
763 if (ret)
764 return ret;
765 if (gfs2_is_jdata(ip))
766 ret = file_write_and_wait(file);
767 if (ret)
768 return ret;
769 gfs2_ail_flush(ip->i_gl, 1);
770 }
771
772 if (mapping->nrpages)
773 ret = file_fdatawait_range(file, start, end);
774
775 return ret ? ret : ret1;
776}
777
778static inline bool should_fault_in_pages(struct iov_iter *i,
779 struct kiocb *iocb,
780 size_t *prev_count,
781 size_t *window_size)
782{
783 size_t count = iov_iter_count(i);
784 size_t size, offs;
785
786 if (!count)
787 return false;
788 if (!user_backed_iter(i))
789 return false;
790
791 /*
792 * Try to fault in multiple pages initially. When that doesn't result
793 * in any progress, fall back to a single page.
794 */
795 size = PAGE_SIZE;
796 offs = offset_in_page(iocb->ki_pos);
797 if (*prev_count != count) {
798 size_t nr_dirtied;
799
800 nr_dirtied = max(current->nr_dirtied_pause -
801 current->nr_dirtied, 8);
802 size = min_t(size_t, SZ_1M, nr_dirtied << PAGE_SHIFT);
803 }
804
805 *prev_count = count;
806 *window_size = size - offs;
807 return true;
808}
809
810static ssize_t gfs2_file_direct_read(struct kiocb *iocb, struct iov_iter *to,
811 struct gfs2_holder *gh)
812{
813 struct file *file = iocb->ki_filp;
814 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
815 size_t prev_count = 0, window_size = 0;
816 size_t read = 0;
817 ssize_t ret;
818
819 /*
820 * In this function, we disable page faults when we're holding the
821 * inode glock while doing I/O. If a page fault occurs, we indicate
822 * that the inode glock may be dropped, fault in the pages manually,
823 * and retry.
824 *
825 * Unlike generic_file_read_iter, for reads, iomap_dio_rw can trigger
826 * physical as well as manual page faults, and we need to disable both
827 * kinds.
828 *
829 * For direct I/O, gfs2 takes the inode glock in deferred mode. This
830 * locking mode is compatible with other deferred holders, so multiple
831 * processes and nodes can do direct I/O to a file at the same time.
832 * There's no guarantee that reads or writes will be atomic. Any
833 * coordination among readers and writers needs to happen externally.
834 */
835
836 if (!iov_iter_count(to))
837 return 0; /* skip atime */
838
839 gfs2_holder_init(ip->i_gl, LM_ST_DEFERRED, 0, gh);
840retry:
841 ret = gfs2_glock_nq(gh);
842 if (ret)
843 goto out_uninit;
844 pagefault_disable();
845 to->nofault = true;
846 ret = iomap_dio_rw(iocb, to, &gfs2_iomap_ops, NULL,
847 IOMAP_DIO_PARTIAL, NULL, read);
848 to->nofault = false;
849 pagefault_enable();
850 if (ret <= 0 && ret != -EFAULT)
851 goto out_unlock;
852 /* No increment (+=) because iomap_dio_rw returns a cumulative value. */
853 if (ret > 0)
854 read = ret;
855
856 if (should_fault_in_pages(to, iocb, &prev_count, &window_size)) {
857 gfs2_glock_dq(gh);
858 window_size -= fault_in_iov_iter_writeable(to, window_size);
859 if (window_size)
860 goto retry;
861 }
862out_unlock:
863 if (gfs2_holder_queued(gh))
864 gfs2_glock_dq(gh);
865out_uninit:
866 gfs2_holder_uninit(gh);
867 /* User space doesn't expect partial success. */
868 if (ret < 0)
869 return ret;
870 return read;
871}
872
873static ssize_t gfs2_file_direct_write(struct kiocb *iocb, struct iov_iter *from,
874 struct gfs2_holder *gh)
875{
876 struct file *file = iocb->ki_filp;
877 struct inode *inode = file->f_mapping->host;
878 struct gfs2_inode *ip = GFS2_I(inode);
879 size_t prev_count = 0, window_size = 0;
880 size_t written = 0;
881 bool enough_retries;
882 ssize_t ret;
883
884 /*
885 * In this function, we disable page faults when we're holding the
886 * inode glock while doing I/O. If a page fault occurs, we indicate
887 * that the inode glock may be dropped, fault in the pages manually,
888 * and retry.
889 *
890 * For writes, iomap_dio_rw only triggers manual page faults, so we
891 * don't need to disable physical ones.
892 */
893
894 /*
895 * Deferred lock, even if its a write, since we do no allocation on
896 * this path. All we need to change is the atime, and this lock mode
897 * ensures that other nodes have flushed their buffered read caches
898 * (i.e. their page cache entries for this inode). We do not,
899 * unfortunately, have the option of only flushing a range like the
900 * VFS does.
901 */
902 gfs2_holder_init(ip->i_gl, LM_ST_DEFERRED, 0, gh);
903retry:
904 ret = gfs2_glock_nq(gh);
905 if (ret)
906 goto out_uninit;
907 /* Silently fall back to buffered I/O when writing beyond EOF */
908 if (iocb->ki_pos + iov_iter_count(from) > i_size_read(&ip->i_inode))
909 goto out_unlock;
910
911 from->nofault = true;
912 ret = iomap_dio_rw(iocb, from, &gfs2_iomap_ops, NULL,
913 IOMAP_DIO_PARTIAL, NULL, written);
914 from->nofault = false;
915 if (ret <= 0) {
916 if (ret == -ENOTBLK)
917 ret = 0;
918 if (ret != -EFAULT)
919 goto out_unlock;
920 }
921 /* No increment (+=) because iomap_dio_rw returns a cumulative value. */
922 if (ret > 0)
923 written = ret;
924
925 enough_retries = prev_count == iov_iter_count(from) &&
926 window_size <= PAGE_SIZE;
927 if (should_fault_in_pages(from, iocb, &prev_count, &window_size)) {
928 gfs2_glock_dq(gh);
929 window_size -= fault_in_iov_iter_readable(from, window_size);
930 if (window_size) {
931 if (!enough_retries)
932 goto retry;
933 /* fall back to buffered I/O */
934 ret = 0;
935 }
936 }
937out_unlock:
938 if (gfs2_holder_queued(gh))
939 gfs2_glock_dq(gh);
940out_uninit:
941 gfs2_holder_uninit(gh);
942 /* User space doesn't expect partial success. */
943 if (ret < 0)
944 return ret;
945 return written;
946}
947
948static ssize_t gfs2_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
949{
950 struct gfs2_inode *ip;
951 struct gfs2_holder gh;
952 size_t prev_count = 0, window_size = 0;
953 size_t read = 0;
954 ssize_t ret;
955
956 /*
957 * In this function, we disable page faults when we're holding the
958 * inode glock while doing I/O. If a page fault occurs, we indicate
959 * that the inode glock may be dropped, fault in the pages manually,
960 * and retry.
961 */
962
963 if (iocb->ki_flags & IOCB_DIRECT)
964 return gfs2_file_direct_read(iocb, to, &gh);
965
966 pagefault_disable();
967 iocb->ki_flags |= IOCB_NOIO;
968 ret = generic_file_read_iter(iocb, to);
969 iocb->ki_flags &= ~IOCB_NOIO;
970 pagefault_enable();
971 if (ret >= 0) {
972 if (!iov_iter_count(to))
973 return ret;
974 read = ret;
975 } else if (ret != -EFAULT) {
976 if (ret != -EAGAIN)
977 return ret;
978 if (iocb->ki_flags & IOCB_NOWAIT)
979 return ret;
980 }
981 ip = GFS2_I(iocb->ki_filp->f_mapping->host);
982 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
983retry:
984 ret = gfs2_glock_nq(&gh);
985 if (ret)
986 goto out_uninit;
987 pagefault_disable();
988 ret = generic_file_read_iter(iocb, to);
989 pagefault_enable();
990 if (ret <= 0 && ret != -EFAULT)
991 goto out_unlock;
992 if (ret > 0)
993 read += ret;
994
995 if (should_fault_in_pages(to, iocb, &prev_count, &window_size)) {
996 gfs2_glock_dq(&gh);
997 window_size -= fault_in_iov_iter_writeable(to, window_size);
998 if (window_size)
999 goto retry;
1000 }
1001out_unlock:
1002 if (gfs2_holder_queued(&gh))
1003 gfs2_glock_dq(&gh);
1004out_uninit:
1005 gfs2_holder_uninit(&gh);
1006 return read ? read : ret;
1007}
1008
1009static ssize_t gfs2_file_buffered_write(struct kiocb *iocb,
1010 struct iov_iter *from,
1011 struct gfs2_holder *gh)
1012{
1013 struct file *file = iocb->ki_filp;
1014 struct inode *inode = file_inode(file);
1015 struct gfs2_inode *ip = GFS2_I(inode);
1016 struct gfs2_sbd *sdp = GFS2_SB(inode);
1017 struct gfs2_holder *statfs_gh = NULL;
1018 size_t prev_count = 0, window_size = 0;
1019 size_t orig_count = iov_iter_count(from);
1020 size_t written = 0;
1021 ssize_t ret;
1022
1023 /*
1024 * In this function, we disable page faults when we're holding the
1025 * inode glock while doing I/O. If a page fault occurs, we indicate
1026 * that the inode glock may be dropped, fault in the pages manually,
1027 * and retry.
1028 */
1029
1030 if (inode == sdp->sd_rindex) {
1031 statfs_gh = kmalloc(sizeof(*statfs_gh), GFP_NOFS);
1032 if (!statfs_gh)
1033 return -ENOMEM;
1034 }
1035
1036 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, gh);
1037 if (should_fault_in_pages(from, iocb, &prev_count, &window_size)) {
1038retry:
1039 window_size -= fault_in_iov_iter_readable(from, window_size);
1040 if (!window_size) {
1041 ret = -EFAULT;
1042 goto out_uninit;
1043 }
1044 from->count = min(from->count, window_size);
1045 }
1046 ret = gfs2_glock_nq(gh);
1047 if (ret)
1048 goto out_uninit;
1049
1050 if (inode == sdp->sd_rindex) {
1051 struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
1052
1053 ret = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE,
1054 GL_NOCACHE, statfs_gh);
1055 if (ret)
1056 goto out_unlock;
1057 }
1058
1059 pagefault_disable();
1060 ret = iomap_file_buffered_write(iocb, from, &gfs2_iomap_ops);
1061 pagefault_enable();
1062 if (ret > 0)
1063 written += ret;
1064
1065 if (inode == sdp->sd_rindex)
1066 gfs2_glock_dq_uninit(statfs_gh);
1067
1068 if (ret <= 0 && ret != -EFAULT)
1069 goto out_unlock;
1070
1071 from->count = orig_count - written;
1072 if (should_fault_in_pages(from, iocb, &prev_count, &window_size)) {
1073 gfs2_glock_dq(gh);
1074 goto retry;
1075 }
1076out_unlock:
1077 if (gfs2_holder_queued(gh))
1078 gfs2_glock_dq(gh);
1079out_uninit:
1080 gfs2_holder_uninit(gh);
1081 kfree(statfs_gh);
1082 from->count = orig_count - written;
1083 return written ? written : ret;
1084}
1085
1086/**
1087 * gfs2_file_write_iter - Perform a write to a file
1088 * @iocb: The io context
1089 * @from: The data to write
1090 *
1091 * We have to do a lock/unlock here to refresh the inode size for
1092 * O_APPEND writes, otherwise we can land up writing at the wrong
1093 * offset. There is still a race, but provided the app is using its
1094 * own file locking, this will make O_APPEND work as expected.
1095 *
1096 */
1097
1098static ssize_t gfs2_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
1099{
1100 struct file *file = iocb->ki_filp;
1101 struct inode *inode = file_inode(file);
1102 struct gfs2_inode *ip = GFS2_I(inode);
1103 struct gfs2_holder gh;
1104 ssize_t ret;
1105
1106 gfs2_size_hint(file, iocb->ki_pos, iov_iter_count(from));
1107
1108 if (iocb->ki_flags & IOCB_APPEND) {
1109 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
1110 if (ret)
1111 return ret;
1112 gfs2_glock_dq_uninit(&gh);
1113 }
1114
1115 inode_lock(inode);
1116 ret = generic_write_checks(iocb, from);
1117 if (ret <= 0)
1118 goto out_unlock;
1119
1120 ret = file_remove_privs(file);
1121 if (ret)
1122 goto out_unlock;
1123
1124 if (iocb->ki_flags & IOCB_DIRECT) {
1125 struct address_space *mapping = file->f_mapping;
1126 ssize_t buffered, ret2;
1127
1128 /*
1129 * Note that under direct I/O, we don't allow and inode
1130 * timestamp updates, so we're not calling file_update_time()
1131 * here.
1132 */
1133
1134 ret = gfs2_file_direct_write(iocb, from, &gh);
1135 if (ret < 0 || !iov_iter_count(from))
1136 goto out_unlock;
1137
1138 iocb->ki_flags |= IOCB_DSYNC;
1139 buffered = gfs2_file_buffered_write(iocb, from, &gh);
1140 if (unlikely(buffered <= 0)) {
1141 if (!ret)
1142 ret = buffered;
1143 goto out_unlock;
1144 }
1145
1146 /*
1147 * We need to ensure that the page cache pages are written to
1148 * disk and invalidated to preserve the expected O_DIRECT
1149 * semantics. If the writeback or invalidate fails, only report
1150 * the direct I/O range as we don't know if the buffered pages
1151 * made it to disk.
1152 */
1153 ret2 = generic_write_sync(iocb, buffered);
1154 invalidate_mapping_pages(mapping,
1155 (iocb->ki_pos - buffered) >> PAGE_SHIFT,
1156 (iocb->ki_pos - 1) >> PAGE_SHIFT);
1157 if (!ret || ret2 > 0)
1158 ret += ret2;
1159 } else {
1160 ret = file_update_time(file);
1161 if (ret)
1162 goto out_unlock;
1163
1164 ret = gfs2_file_buffered_write(iocb, from, &gh);
1165 if (likely(ret > 0))
1166 ret = generic_write_sync(iocb, ret);
1167 }
1168
1169out_unlock:
1170 inode_unlock(inode);
1171 return ret;
1172}
1173
1174static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len,
1175 int mode)
1176{
1177 struct super_block *sb = inode->i_sb;
1178 struct gfs2_inode *ip = GFS2_I(inode);
1179 loff_t end = offset + len;
1180 struct buffer_head *dibh;
1181 int error;
1182
1183 error = gfs2_meta_inode_buffer(ip, &dibh);
1184 if (unlikely(error))
1185 return error;
1186
1187 gfs2_trans_add_meta(ip->i_gl, dibh);
1188
1189 if (gfs2_is_stuffed(ip)) {
1190 error = gfs2_unstuff_dinode(ip);
1191 if (unlikely(error))
1192 goto out;
1193 }
1194
1195 while (offset < end) {
1196 struct iomap iomap = { };
1197
1198 error = gfs2_iomap_alloc(inode, offset, end - offset, &iomap);
1199 if (error)
1200 goto out;
1201 offset = iomap.offset + iomap.length;
1202 if (!(iomap.flags & IOMAP_F_NEW))
1203 continue;
1204 error = sb_issue_zeroout(sb, iomap.addr >> inode->i_blkbits,
1205 iomap.length >> inode->i_blkbits,
1206 GFP_NOFS);
1207 if (error) {
1208 fs_err(GFS2_SB(inode), "Failed to zero data buffers\n");
1209 goto out;
1210 }
1211 }
1212out:
1213 brelse(dibh);
1214 return error;
1215}
1216
1217/**
1218 * calc_max_reserv() - Reverse of write_calc_reserv. Given a number of
1219 * blocks, determine how many bytes can be written.
1220 * @ip: The inode in question.
1221 * @len: Max cap of bytes. What we return in *len must be <= this.
1222 * @data_blocks: Compute and return the number of data blocks needed
1223 * @ind_blocks: Compute and return the number of indirect blocks needed
1224 * @max_blocks: The total blocks available to work with.
1225 *
1226 * Returns: void, but @len, @data_blocks and @ind_blocks are filled in.
1227 */
1228static void calc_max_reserv(struct gfs2_inode *ip, loff_t *len,
1229 unsigned int *data_blocks, unsigned int *ind_blocks,
1230 unsigned int max_blocks)
1231{
1232 loff_t max = *len;
1233 const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1234 unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1);
1235
1236 for (tmp = max_data; tmp > sdp->sd_diptrs;) {
1237 tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
1238 max_data -= tmp;
1239 }
1240
1241 *data_blocks = max_data;
1242 *ind_blocks = max_blocks - max_data;
1243 *len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift;
1244 if (*len > max) {
1245 *len = max;
1246 gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks);
1247 }
1248}
1249
1250static long __gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
1251{
1252 struct inode *inode = file_inode(file);
1253 struct gfs2_sbd *sdp = GFS2_SB(inode);
1254 struct gfs2_inode *ip = GFS2_I(inode);
1255 struct gfs2_alloc_parms ap = {};
1256 unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
1257 loff_t bytes, max_bytes, max_blks;
1258 int error;
1259 const loff_t pos = offset;
1260 const loff_t count = len;
1261 loff_t bsize_mask = ~((loff_t)sdp->sd_sb.sb_bsize - 1);
1262 loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift;
1263 loff_t max_chunk_size = UINT_MAX & bsize_mask;
1264
1265 next = (next + 1) << sdp->sd_sb.sb_bsize_shift;
1266
1267 offset &= bsize_mask;
1268
1269 len = next - offset;
1270 bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2;
1271 if (!bytes)
1272 bytes = UINT_MAX;
1273 bytes &= bsize_mask;
1274 if (bytes == 0)
1275 bytes = sdp->sd_sb.sb_bsize;
1276
1277 gfs2_size_hint(file, offset, len);
1278
1279 gfs2_write_calc_reserv(ip, PAGE_SIZE, &data_blocks, &ind_blocks);
1280 ap.min_target = data_blocks + ind_blocks;
1281
1282 while (len > 0) {
1283 if (len < bytes)
1284 bytes = len;
1285 if (!gfs2_write_alloc_required(ip, offset, bytes)) {
1286 len -= bytes;
1287 offset += bytes;
1288 continue;
1289 }
1290
1291 /* We need to determine how many bytes we can actually
1292 * fallocate without exceeding quota or going over the
1293 * end of the fs. We start off optimistically by assuming
1294 * we can write max_bytes */
1295 max_bytes = (len > max_chunk_size) ? max_chunk_size : len;
1296
1297 /* Since max_bytes is most likely a theoretical max, we
1298 * calculate a more realistic 'bytes' to serve as a good
1299 * starting point for the number of bytes we may be able
1300 * to write */
1301 gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks);
1302 ap.target = data_blocks + ind_blocks;
1303
1304 error = gfs2_quota_lock_check(ip, &ap);
1305 if (error)
1306 return error;
1307 /* ap.allowed tells us how many blocks quota will allow
1308 * us to write. Check if this reduces max_blks */
1309 max_blks = UINT_MAX;
1310 if (ap.allowed)
1311 max_blks = ap.allowed;
1312
1313 error = gfs2_inplace_reserve(ip, &ap);
1314 if (error)
1315 goto out_qunlock;
1316
1317 /* check if the selected rgrp limits our max_blks further */
1318 if (ip->i_res.rs_reserved < max_blks)
1319 max_blks = ip->i_res.rs_reserved;
1320
1321 /* Almost done. Calculate bytes that can be written using
1322 * max_blks. We also recompute max_bytes, data_blocks and
1323 * ind_blocks */
1324 calc_max_reserv(ip, &max_bytes, &data_blocks,
1325 &ind_blocks, max_blks);
1326
1327 rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA +
1328 RES_RG_HDR + gfs2_rg_blocks(ip, data_blocks + ind_blocks);
1329 if (gfs2_is_jdata(ip))
1330 rblocks += data_blocks ? data_blocks : 1;
1331
1332 error = gfs2_trans_begin(sdp, rblocks,
1333 PAGE_SIZE >> inode->i_blkbits);
1334 if (error)
1335 goto out_trans_fail;
1336
1337 error = fallocate_chunk(inode, offset, max_bytes, mode);
1338 gfs2_trans_end(sdp);
1339
1340 if (error)
1341 goto out_trans_fail;
1342
1343 len -= max_bytes;
1344 offset += max_bytes;
1345 gfs2_inplace_release(ip);
1346 gfs2_quota_unlock(ip);
1347 }
1348
1349 if (!(mode & FALLOC_FL_KEEP_SIZE) && (pos + count) > inode->i_size)
1350 i_size_write(inode, pos + count);
1351 file_update_time(file);
1352 mark_inode_dirty(inode);
1353
1354 if ((file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host))
1355 return vfs_fsync_range(file, pos, pos + count - 1,
1356 (file->f_flags & __O_SYNC) ? 0 : 1);
1357 return 0;
1358
1359out_trans_fail:
1360 gfs2_inplace_release(ip);
1361out_qunlock:
1362 gfs2_quota_unlock(ip);
1363 return error;
1364}
1365
1366static long gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
1367{
1368 struct inode *inode = file_inode(file);
1369 struct gfs2_sbd *sdp = GFS2_SB(inode);
1370 struct gfs2_inode *ip = GFS2_I(inode);
1371 struct gfs2_holder gh;
1372 int ret;
1373
1374 if (mode & ~(FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE))
1375 return -EOPNOTSUPP;
1376 /* fallocate is needed by gfs2_grow to reserve space in the rindex */
1377 if (gfs2_is_jdata(ip) && inode != sdp->sd_rindex)
1378 return -EOPNOTSUPP;
1379
1380 inode_lock(inode);
1381
1382 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
1383 ret = gfs2_glock_nq(&gh);
1384 if (ret)
1385 goto out_uninit;
1386
1387 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
1388 (offset + len) > inode->i_size) {
1389 ret = inode_newsize_ok(inode, offset + len);
1390 if (ret)
1391 goto out_unlock;
1392 }
1393
1394 ret = get_write_access(inode);
1395 if (ret)
1396 goto out_unlock;
1397
1398 if (mode & FALLOC_FL_PUNCH_HOLE) {
1399 ret = __gfs2_punch_hole(file, offset, len);
1400 } else {
1401 ret = __gfs2_fallocate(file, mode, offset, len);
1402 if (ret)
1403 gfs2_rs_deltree(&ip->i_res);
1404 }
1405
1406 put_write_access(inode);
1407out_unlock:
1408 gfs2_glock_dq(&gh);
1409out_uninit:
1410 gfs2_holder_uninit(&gh);
1411 inode_unlock(inode);
1412 return ret;
1413}
1414
1415static ssize_t gfs2_file_splice_write(struct pipe_inode_info *pipe,
1416 struct file *out, loff_t *ppos,
1417 size_t len, unsigned int flags)
1418{
1419 ssize_t ret;
1420
1421 gfs2_size_hint(out, *ppos, len);
1422
1423 ret = iter_file_splice_write(pipe, out, ppos, len, flags);
1424 return ret;
1425}
1426
1427#ifdef CONFIG_GFS2_FS_LOCKING_DLM
1428
1429/**
1430 * gfs2_lock - acquire/release a posix lock on a file
1431 * @file: the file pointer
1432 * @cmd: either modify or retrieve lock state, possibly wait
1433 * @fl: type and range of lock
1434 *
1435 * Returns: errno
1436 */
1437
1438static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
1439{
1440 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
1441 struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
1442 struct lm_lockstruct *ls = &sdp->sd_lockstruct;
1443
1444 if (!(fl->c.flc_flags & FL_POSIX))
1445 return -ENOLCK;
1446 if (gfs2_withdrawing_or_withdrawn(sdp)) {
1447 if (lock_is_unlock(fl))
1448 locks_lock_file_wait(file, fl);
1449 return -EIO;
1450 }
1451 if (cmd == F_CANCELLK)
1452 return dlm_posix_cancel(ls->ls_dlm, ip->i_no_addr, file, fl);
1453 else if (IS_GETLK(cmd))
1454 return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl);
1455 else if (lock_is_unlock(fl))
1456 return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl);
1457 else
1458 return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl);
1459}
1460
1461static void __flock_holder_uninit(struct file *file, struct gfs2_holder *fl_gh)
1462{
1463 struct gfs2_glock *gl = gfs2_glock_hold(fl_gh->gh_gl);
1464
1465 /*
1466 * Make sure gfs2_glock_put() won't sleep under the file->f_lock
1467 * spinlock.
1468 */
1469
1470 spin_lock(&file->f_lock);
1471 gfs2_holder_uninit(fl_gh);
1472 spin_unlock(&file->f_lock);
1473 gfs2_glock_put(gl);
1474}
1475
1476static int do_flock(struct file *file, int cmd, struct file_lock *fl)
1477{
1478 struct gfs2_file *fp = file->private_data;
1479 struct gfs2_holder *fl_gh = &fp->f_fl_gh;
1480 struct gfs2_inode *ip = GFS2_I(file_inode(file));
1481 struct gfs2_glock *gl;
1482 unsigned int state;
1483 u16 flags;
1484 int error = 0;
1485 int sleeptime;
1486
1487 state = lock_is_write(fl) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
1488 flags = GL_EXACT | GL_NOPID;
1489 if (!IS_SETLKW(cmd))
1490 flags |= LM_FLAG_TRY_1CB;
1491
1492 mutex_lock(&fp->f_fl_mutex);
1493
1494 if (gfs2_holder_initialized(fl_gh)) {
1495 struct file_lock request;
1496 if (fl_gh->gh_state == state)
1497 goto out;
1498 locks_init_lock(&request);
1499 request.c.flc_type = F_UNLCK;
1500 request.c.flc_flags = FL_FLOCK;
1501 locks_lock_file_wait(file, &request);
1502 gfs2_glock_dq(fl_gh);
1503 gfs2_holder_reinit(state, flags, fl_gh);
1504 } else {
1505 error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr,
1506 &gfs2_flock_glops, CREATE, &gl);
1507 if (error)
1508 goto out;
1509 spin_lock(&file->f_lock);
1510 gfs2_holder_init(gl, state, flags, fl_gh);
1511 spin_unlock(&file->f_lock);
1512 gfs2_glock_put(gl);
1513 }
1514 for (sleeptime = 1; sleeptime <= 4; sleeptime <<= 1) {
1515 error = gfs2_glock_nq(fl_gh);
1516 if (error != GLR_TRYFAILED)
1517 break;
1518 fl_gh->gh_flags &= ~LM_FLAG_TRY_1CB;
1519 fl_gh->gh_flags |= LM_FLAG_TRY;
1520 msleep(sleeptime);
1521 }
1522 if (error) {
1523 __flock_holder_uninit(file, fl_gh);
1524 if (error == GLR_TRYFAILED)
1525 error = -EAGAIN;
1526 } else {
1527 error = locks_lock_file_wait(file, fl);
1528 gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error);
1529 }
1530
1531out:
1532 mutex_unlock(&fp->f_fl_mutex);
1533 return error;
1534}
1535
1536static void do_unflock(struct file *file, struct file_lock *fl)
1537{
1538 struct gfs2_file *fp = file->private_data;
1539 struct gfs2_holder *fl_gh = &fp->f_fl_gh;
1540
1541 mutex_lock(&fp->f_fl_mutex);
1542 locks_lock_file_wait(file, fl);
1543 if (gfs2_holder_initialized(fl_gh)) {
1544 gfs2_glock_dq(fl_gh);
1545 __flock_holder_uninit(file, fl_gh);
1546 }
1547 mutex_unlock(&fp->f_fl_mutex);
1548}
1549
1550/**
1551 * gfs2_flock - acquire/release a flock lock on a file
1552 * @file: the file pointer
1553 * @cmd: either modify or retrieve lock state, possibly wait
1554 * @fl: type and range of lock
1555 *
1556 * Returns: errno
1557 */
1558
1559static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl)
1560{
1561 if (!(fl->c.flc_flags & FL_FLOCK))
1562 return -ENOLCK;
1563
1564 if (lock_is_unlock(fl)) {
1565 do_unflock(file, fl);
1566 return 0;
1567 } else {
1568 return do_flock(file, cmd, fl);
1569 }
1570}
1571
1572const struct file_operations gfs2_file_fops = {
1573 .llseek = gfs2_llseek,
1574 .read_iter = gfs2_file_read_iter,
1575 .write_iter = gfs2_file_write_iter,
1576 .iopoll = iocb_bio_iopoll,
1577 .unlocked_ioctl = gfs2_ioctl,
1578 .compat_ioctl = gfs2_compat_ioctl,
1579 .mmap = gfs2_mmap,
1580 .open = gfs2_open,
1581 .release = gfs2_release,
1582 .fsync = gfs2_fsync,
1583 .lock = gfs2_lock,
1584 .flock = gfs2_flock,
1585 .splice_read = copy_splice_read,
1586 .splice_write = gfs2_file_splice_write,
1587 .setlease = simple_nosetlease,
1588 .fallocate = gfs2_fallocate,
1589};
1590
1591const struct file_operations gfs2_dir_fops = {
1592 .iterate_shared = gfs2_readdir,
1593 .unlocked_ioctl = gfs2_ioctl,
1594 .compat_ioctl = gfs2_compat_ioctl,
1595 .open = gfs2_open,
1596 .release = gfs2_release,
1597 .fsync = gfs2_fsync,
1598 .lock = gfs2_lock,
1599 .flock = gfs2_flock,
1600 .llseek = default_llseek,
1601};
1602
1603#endif /* CONFIG_GFS2_FS_LOCKING_DLM */
1604
1605const struct file_operations gfs2_file_fops_nolock = {
1606 .llseek = gfs2_llseek,
1607 .read_iter = gfs2_file_read_iter,
1608 .write_iter = gfs2_file_write_iter,
1609 .iopoll = iocb_bio_iopoll,
1610 .unlocked_ioctl = gfs2_ioctl,
1611 .compat_ioctl = gfs2_compat_ioctl,
1612 .mmap = gfs2_mmap,
1613 .open = gfs2_open,
1614 .release = gfs2_release,
1615 .fsync = gfs2_fsync,
1616 .splice_read = copy_splice_read,
1617 .splice_write = gfs2_file_splice_write,
1618 .setlease = generic_setlease,
1619 .fallocate = gfs2_fallocate,
1620};
1621
1622const struct file_operations gfs2_dir_fops_nolock = {
1623 .iterate_shared = gfs2_readdir,
1624 .unlocked_ioctl = gfs2_ioctl,
1625 .compat_ioctl = gfs2_compat_ioctl,
1626 .open = gfs2_open,
1627 .release = gfs2_release,
1628 .fsync = gfs2_fsync,
1629 .llseek = default_llseek,
1630};
1631
Linux 6.x block layer and io_uring tree(s)