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(inode: 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(gl: ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
67 gh: &i_gh);
68 if (!error) {
69 error = generic_file_llseek(file, offset, whence);
70 gfs2_glock_dq_uninit(gh: &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(inode: dir);
109 struct gfs2_holder d_gh;
110 int error;
111
112 error = gfs2_glock_nq_init(gl: dip->i_gl, LM_ST_SHARED, flags: 0, gh: &d_gh);
113 if (error)
114 return error;
115
116 error = gfs2_dir_read(inode: dir, ctx, f_ra: &file->f_ra);
117
118 gfs2_glock_dq_uninit(gh: &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(gl: ip->i_gl, LM_ST_SHARED, flags: 0, gh: &gh);
170 error = gfs2_glock_nq(gh: &gh);
171 if (error)
172 goto out_uninit;
173
174 fsflags = gfs2_gfsflags_to_fsflags(inode, gfsflags: ip->i_diskflags);
175
176 fileattr_fill_flags(fa, flags: fsflags);
177
178 gfs2_glock_dq(gh: &gh);
179out_uninit:
180 gfs2_holder_uninit(gh: &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(mode: 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(gl: ip->i_gl, LM_ST_EXCLUSIVE, flags: 0, gh: &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(idmap: &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, gl: 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(mapping: 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, revokes: 0);
258 if (error)
259 goto out;
260 error = gfs2_meta_inode_buffer(ip, bhp: &bh);
261 if (error)
262 goto out_trans_end;
263 inode_set_ctime_current(inode);
264 gfs2_trans_add_meta(gl: ip->i_gl, bh);
265 ip->i_diskflags = new_flags;
266 gfs2_dinode_out(ip, buf: 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: &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, reqflags: gfsflags, mask);
311}
312
313static int gfs2_getlabel(struct file *filp, char __user *label)
314{
315 struct inode *inode = file_inode(f: filp);
316 struct gfs2_sbd *sdp = GFS2_SB(inode);
317
318 if (copy_to_user(to: label, from: 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, argp: (void __user *)arg);
329 case FS_IOC_GETFSLABEL:
330 return gfs2_getlabel(filp, label: (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, arg: (unsigned long)compat_ptr(uptr: 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(f: 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(v: &ip->i_sizehint))
375 atomic_set(v: &ip->i_sizehint, i: hint);
376}
377
378/**
379 * gfs2_allocate_page_backing - Allocate blocks for a write fault
380 * @page: The (locked) page to allocate backing for
381 * @length: Size of the allocation
382 *
383 * We try to allocate all the blocks required for the page in one go. This
384 * might fail for various reasons, so we keep trying until all the blocks to
385 * back this page are allocated. If some of the blocks are already allocated,
386 * that is ok too.
387 */
388static int gfs2_allocate_page_backing(struct page *page, unsigned int length)
389{
390 u64 pos = page_offset(page);
391
392 do {
393 struct iomap iomap = { };
394
395 if (gfs2_iomap_alloc(inode: page->mapping->host, pos, length, iomap: &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 page *page = vmf->page;
418 struct inode *inode = file_inode(f: 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 offset = page_offset(page);
423 unsigned int data_blocks, ind_blocks, rblocks;
424 vm_fault_t ret = VM_FAULT_LOCKED;
425 struct gfs2_holder gh;
426 unsigned int length;
427 loff_t size;
428 int err;
429
430 sb_start_pagefault(sb: inode->i_sb);
431
432 gfs2_holder_init(gl: ip->i_gl, LM_ST_EXCLUSIVE, flags: 0, gh: &gh);
433 err = gfs2_glock_nq(gh: &gh);
434 if (err) {
435 ret = vmf_fs_error(err);
436 goto out_uninit;
437 }
438
439 /* Check page index against inode size */
440 size = i_size_read(inode);
441 if (offset >= size) {
442 ret = VM_FAULT_SIGBUS;
443 goto out_unlock;
444 }
445
446 /* Update file times before taking page lock */
447 file_update_time(file: vmf->vma->vm_file);
448
449 /* page is wholly or partially inside EOF */
450 if (size - offset < PAGE_SIZE)
451 length = size - offset;
452 else
453 length = PAGE_SIZE;
454
455 gfs2_size_hint(filep: vmf->vma->vm_file, offset, size: length);
456
457 set_bit(nr: GLF_DIRTY, addr: &ip->i_gl->gl_flags);
458 set_bit(nr: GIF_SW_PAGED, addr: &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, offset, len: length)) {
467 lock_page(page);
468 if (!PageUptodate(page) || page->mapping != inode->i_mapping) {
469 ret = VM_FAULT_NOPAGE;
470 unlock_page(page);
471 }
472 goto out_unlock;
473 }
474
475 err = gfs2_rindex_update(sdp);
476 if (err) {
477 ret = vmf_fs_error(err);
478 goto out_unlock;
479 }
480
481 gfs2_write_calc_reserv(ip, len: length, data_blocks: &data_blocks, ind_blocks: &ind_blocks);
482 ap.target = data_blocks + ind_blocks;
483 err = gfs2_quota_lock_check(ip, ap: &ap);
484 if (err) {
485 ret = vmf_fs_error(err);
486 goto out_unlock;
487 }
488 err = gfs2_inplace_reserve(ip, ap: &ap);
489 if (err) {
490 ret = vmf_fs_error(err);
491 goto out_quota_unlock;
492 }
493
494 rblocks = RES_DINODE + ind_blocks;
495 if (gfs2_is_jdata(ip))
496 rblocks += data_blocks ? data_blocks : 1;
497 if (ind_blocks || data_blocks) {
498 rblocks += RES_STATFS + RES_QUOTA;
499 rblocks += gfs2_rg_blocks(ip, requested: data_blocks + ind_blocks);
500 }
501 err = gfs2_trans_begin(sdp, blocks: rblocks, revokes: 0);
502 if (err) {
503 ret = vmf_fs_error(err);
504 goto out_trans_fail;
505 }
506
507 /* Unstuff, if required, and allocate backing blocks for page */
508 if (gfs2_is_stuffed(ip)) {
509 err = gfs2_unstuff_dinode(ip);
510 if (err) {
511 ret = vmf_fs_error(err);
512 goto out_trans_end;
513 }
514 }
515
516 lock_page(page);
517 /* If truncated, we must retry the operation, we may have raced
518 * with the glock demotion code.
519 */
520 if (!PageUptodate(page) || page->mapping != inode->i_mapping) {
521 ret = VM_FAULT_NOPAGE;
522 goto out_page_locked;
523 }
524
525 err = gfs2_allocate_page_backing(page, length);
526 if (err)
527 ret = vmf_fs_error(err);
528
529out_page_locked:
530 if (ret != VM_FAULT_LOCKED)
531 unlock_page(page);
532out_trans_end:
533 gfs2_trans_end(sdp);
534out_trans_fail:
535 gfs2_inplace_release(ip);
536out_quota_unlock:
537 gfs2_quota_unlock(ip);
538out_unlock:
539 gfs2_glock_dq(gh: &gh);
540out_uninit:
541 gfs2_holder_uninit(gh: &gh);
542 if (ret == VM_FAULT_LOCKED) {
543 set_page_dirty(page);
544 wait_for_stable_page(page);
545 }
546 sb_end_pagefault(sb: inode->i_sb);
547 return ret;
548}
549
550static vm_fault_t gfs2_fault(struct vm_fault *vmf)
551{
552 struct inode *inode = file_inode(f: vmf->vma->vm_file);
553 struct gfs2_inode *ip = GFS2_I(inode);
554 struct gfs2_holder gh;
555 vm_fault_t ret;
556 int err;
557
558 gfs2_holder_init(gl: ip->i_gl, LM_ST_SHARED, flags: 0, gh: &gh);
559 err = gfs2_glock_nq(gh: &gh);
560 if (err) {
561 ret = vmf_fs_error(err);
562 goto out_uninit;
563 }
564 ret = filemap_fault(vmf);
565 gfs2_glock_dq(gh: &gh);
566out_uninit:
567 gfs2_holder_uninit(gh: &gh);
568 return ret;
569}
570
571static const struct vm_operations_struct gfs2_vm_ops = {
572 .fault = gfs2_fault,
573 .map_pages = filemap_map_pages,
574 .page_mkwrite = gfs2_page_mkwrite,
575};
576
577/**
578 * gfs2_mmap
579 * @file: The file to map
580 * @vma: The VMA which described the mapping
581 *
582 * There is no need to get a lock here unless we should be updating
583 * atime. We ignore any locking errors since the only consequence is
584 * a missed atime update (which will just be deferred until later).
585 *
586 * Returns: 0
587 */
588
589static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
590{
591 struct gfs2_inode *ip = GFS2_I(inode: file->f_mapping->host);
592
593 if (!(file->f_flags & O_NOATIME) &&
594 !IS_NOATIME(&ip->i_inode)) {
595 struct gfs2_holder i_gh;
596 int error;
597
598 error = gfs2_glock_nq_init(gl: ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
599 gh: &i_gh);
600 if (error)
601 return error;
602 /* grab lock to update inode */
603 gfs2_glock_dq_uninit(gh: &i_gh);
604 file_accessed(file);
605 }
606 vma->vm_ops = &gfs2_vm_ops;
607
608 return 0;
609}
610
611/**
612 * gfs2_open_common - This is common to open and atomic_open
613 * @inode: The inode being opened
614 * @file: The file being opened
615 *
616 * This maybe called under a glock or not depending upon how it has
617 * been called. We must always be called under a glock for regular
618 * files, however. For other file types, it does not matter whether
619 * we hold the glock or not.
620 *
621 * Returns: Error code or 0 for success
622 */
623
624int gfs2_open_common(struct inode *inode, struct file *file)
625{
626 struct gfs2_file *fp;
627 int ret;
628
629 if (S_ISREG(inode->i_mode)) {
630 ret = generic_file_open(inode, filp: file);
631 if (ret)
632 return ret;
633
634 if (!gfs2_is_jdata(ip: GFS2_I(inode)))
635 file->f_mode |= FMODE_CAN_ODIRECT;
636 }
637
638 fp = kzalloc(size: sizeof(struct gfs2_file), GFP_NOFS);
639 if (!fp)
640 return -ENOMEM;
641
642 mutex_init(&fp->f_fl_mutex);
643
644 gfs2_assert_warn(GFS2_SB(inode), !file->private_data);
645 file->private_data = fp;
646 if (file->f_mode & FMODE_WRITE) {
647 ret = gfs2_qa_get(ip: GFS2_I(inode));
648 if (ret)
649 goto fail;
650 }
651 return 0;
652
653fail:
654 kfree(objp: file->private_data);
655 file->private_data = NULL;
656 return ret;
657}
658
659/**
660 * gfs2_open - open a file
661 * @inode: the inode to open
662 * @file: the struct file for this opening
663 *
664 * After atomic_open, this function is only used for opening files
665 * which are already cached. We must still get the glock for regular
666 * files to ensure that we have the file size uptodate for the large
667 * file check which is in the common code. That is only an issue for
668 * regular files though.
669 *
670 * Returns: errno
671 */
672
673static int gfs2_open(struct inode *inode, struct file *file)
674{
675 struct gfs2_inode *ip = GFS2_I(inode);
676 struct gfs2_holder i_gh;
677 int error;
678 bool need_unlock = false;
679
680 if (S_ISREG(ip->i_inode.i_mode)) {
681 error = gfs2_glock_nq_init(gl: ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
682 gh: &i_gh);
683 if (error)
684 return error;
685 need_unlock = true;
686 }
687
688 error = gfs2_open_common(inode, file);
689
690 if (need_unlock)
691 gfs2_glock_dq_uninit(gh: &i_gh);
692
693 return error;
694}
695
696/**
697 * gfs2_release - called to close a struct file
698 * @inode: the inode the struct file belongs to
699 * @file: the struct file being closed
700 *
701 * Returns: errno
702 */
703
704static int gfs2_release(struct inode *inode, struct file *file)
705{
706 struct gfs2_inode *ip = GFS2_I(inode);
707
708 kfree(objp: file->private_data);
709 file->private_data = NULL;
710
711 if (file->f_mode & FMODE_WRITE) {
712 if (gfs2_rs_active(rs: &ip->i_res))
713 gfs2_rs_delete(ip);
714 gfs2_qa_put(ip);
715 }
716 return 0;
717}
718
719/**
720 * gfs2_fsync - sync the dirty data for a file (across the cluster)
721 * @file: the file that points to the dentry
722 * @start: the start position in the file to sync
723 * @end: the end position in the file to sync
724 * @datasync: set if we can ignore timestamp changes
725 *
726 * We split the data flushing here so that we don't wait for the data
727 * until after we've also sent the metadata to disk. Note that for
728 * data=ordered, we will write & wait for the data at the log flush
729 * stage anyway, so this is unlikely to make much of a difference
730 * except in the data=writeback case.
731 *
732 * If the fdatawrite fails due to any reason except -EIO, we will
733 * continue the remainder of the fsync, although we'll still report
734 * the error at the end. This is to match filemap_write_and_wait_range()
735 * behaviour.
736 *
737 * Returns: errno
738 */
739
740static int gfs2_fsync(struct file *file, loff_t start, loff_t end,
741 int datasync)
742{
743 struct address_space *mapping = file->f_mapping;
744 struct inode *inode = mapping->host;
745 int sync_state = inode->i_state & I_DIRTY;
746 struct gfs2_inode *ip = GFS2_I(inode);
747 int ret = 0, ret1 = 0;
748
749 if (mapping->nrpages) {
750 ret1 = filemap_fdatawrite_range(mapping, start, end);
751 if (ret1 == -EIO)
752 return ret1;
753 }
754
755 if (!gfs2_is_jdata(ip))
756 sync_state &= ~I_DIRTY_PAGES;
757 if (datasync)
758 sync_state &= ~I_DIRTY_SYNC;
759
760 if (sync_state) {
761 ret = sync_inode_metadata(inode, wait: 1);
762 if (ret)
763 return ret;
764 if (gfs2_is_jdata(ip))
765 ret = file_write_and_wait(file);
766 if (ret)
767 return ret;
768 gfs2_ail_flush(gl: ip->i_gl, fsync: 1);
769 }
770
771 if (mapping->nrpages)
772 ret = file_fdatawait_range(file, lstart: start, lend: end);
773
774 return ret ? ret : ret1;
775}
776
777static inline bool should_fault_in_pages(struct iov_iter *i,
778 struct kiocb *iocb,
779 size_t *prev_count,
780 size_t *window_size)
781{
782 size_t count = iov_iter_count(i);
783 size_t size, offs;
784
785 if (!count)
786 return false;
787 if (!user_backed_iter(i))
788 return false;
789
790 /*
791 * Try to fault in multiple pages initially. When that doesn't result
792 * in any progress, fall back to a single page.
793 */
794 size = PAGE_SIZE;
795 offs = offset_in_page(iocb->ki_pos);
796 if (*prev_count != count) {
797 size_t nr_dirtied;
798
799 nr_dirtied = max(current->nr_dirtied_pause -
800 current->nr_dirtied, 8);
801 size = min_t(size_t, SZ_1M, nr_dirtied << PAGE_SHIFT);
802 }
803
804 *prev_count = count;
805 *window_size = size - offs;
806 return true;
807}
808
809static ssize_t gfs2_file_direct_read(struct kiocb *iocb, struct iov_iter *to,
810 struct gfs2_holder *gh)
811{
812 struct file *file = iocb->ki_filp;
813 struct gfs2_inode *ip = GFS2_I(inode: file->f_mapping->host);
814 size_t prev_count = 0, window_size = 0;
815 size_t read = 0;
816 ssize_t ret;
817
818 /*
819 * In this function, we disable page faults when we're holding the
820 * inode glock while doing I/O. If a page fault occurs, we indicate
821 * that the inode glock may be dropped, fault in the pages manually,
822 * and retry.
823 *
824 * Unlike generic_file_read_iter, for reads, iomap_dio_rw can trigger
825 * physical as well as manual page faults, and we need to disable both
826 * kinds.
827 *
828 * For direct I/O, gfs2 takes the inode glock in deferred mode. This
829 * locking mode is compatible with other deferred holders, so multiple
830 * processes and nodes can do direct I/O to a file at the same time.
831 * There's no guarantee that reads or writes will be atomic. Any
832 * coordination among readers and writers needs to happen externally.
833 */
834
835 if (!iov_iter_count(i: to))
836 return 0; /* skip atime */
837
838 gfs2_holder_init(gl: ip->i_gl, LM_ST_DEFERRED, flags: 0, gh);
839retry:
840 ret = gfs2_glock_nq(gh);
841 if (ret)
842 goto out_uninit;
843 pagefault_disable();
844 to->nofault = true;
845 ret = iomap_dio_rw(iocb, iter: to, ops: &gfs2_iomap_ops, NULL,
846 IOMAP_DIO_PARTIAL, NULL, done_before: read);
847 to->nofault = false;
848 pagefault_enable();
849 if (ret <= 0 && ret != -EFAULT)
850 goto out_unlock;
851 /* No increment (+=) because iomap_dio_rw returns a cumulative value. */
852 if (ret > 0)
853 read = ret;
854
855 if (should_fault_in_pages(i: to, iocb, prev_count: &prev_count, window_size: &window_size)) {
856 gfs2_glock_dq(gh);
857 window_size -= fault_in_iov_iter_writeable(i: to, bytes: window_size);
858 if (window_size)
859 goto retry;
860 }
861out_unlock:
862 if (gfs2_holder_queued(gh))
863 gfs2_glock_dq(gh);
864out_uninit:
865 gfs2_holder_uninit(gh);
866 /* User space doesn't expect partial success. */
867 if (ret < 0)
868 return ret;
869 return read;
870}
871
872static ssize_t gfs2_file_direct_write(struct kiocb *iocb, struct iov_iter *from,
873 struct gfs2_holder *gh)
874{
875 struct file *file = iocb->ki_filp;
876 struct inode *inode = file->f_mapping->host;
877 struct gfs2_inode *ip = GFS2_I(inode);
878 size_t prev_count = 0, window_size = 0;
879 size_t written = 0;
880 bool enough_retries;
881 ssize_t ret;
882
883 /*
884 * In this function, we disable page faults when we're holding the
885 * inode glock while doing I/O. If a page fault occurs, we indicate
886 * that the inode glock may be dropped, fault in the pages manually,
887 * and retry.
888 *
889 * For writes, iomap_dio_rw only triggers manual page faults, so we
890 * don't need to disable physical ones.
891 */
892
893 /*
894 * Deferred lock, even if its a write, since we do no allocation on
895 * this path. All we need to change is the atime, and this lock mode
896 * ensures that other nodes have flushed their buffered read caches
897 * (i.e. their page cache entries for this inode). We do not,
898 * unfortunately, have the option of only flushing a range like the
899 * VFS does.
900 */
901 gfs2_holder_init(gl: ip->i_gl, LM_ST_DEFERRED, flags: 0, gh);
902retry:
903 ret = gfs2_glock_nq(gh);
904 if (ret)
905 goto out_uninit;
906 /* Silently fall back to buffered I/O when writing beyond EOF */
907 if (iocb->ki_pos + iov_iter_count(i: from) > i_size_read(inode: &ip->i_inode))
908 goto out_unlock;
909
910 from->nofault = true;
911 ret = iomap_dio_rw(iocb, iter: from, ops: &gfs2_iomap_ops, NULL,
912 IOMAP_DIO_PARTIAL, NULL, done_before: written);
913 from->nofault = false;
914 if (ret <= 0) {
915 if (ret == -ENOTBLK)
916 ret = 0;
917 if (ret != -EFAULT)
918 goto out_unlock;
919 }
920 /* No increment (+=) because iomap_dio_rw returns a cumulative value. */
921 if (ret > 0)
922 written = ret;
923
924 enough_retries = prev_count == iov_iter_count(i: from) &&
925 window_size <= PAGE_SIZE;
926 if (should_fault_in_pages(i: from, iocb, prev_count: &prev_count, window_size: &window_size)) {
927 gfs2_glock_dq(gh);
928 window_size -= fault_in_iov_iter_readable(i: from, bytes: window_size);
929 if (window_size) {
930 if (!enough_retries)
931 goto retry;
932 /* fall back to buffered I/O */
933 ret = 0;
934 }
935 }
936out_unlock:
937 if (gfs2_holder_queued(gh))
938 gfs2_glock_dq(gh);
939out_uninit:
940 gfs2_holder_uninit(gh);
941 /* User space doesn't expect partial success. */
942 if (ret < 0)
943 return ret;
944 return written;
945}
946
947static ssize_t gfs2_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
948{
949 struct gfs2_inode *ip;
950 struct gfs2_holder gh;
951 size_t prev_count = 0, window_size = 0;
952 size_t read = 0;
953 ssize_t ret;
954
955 /*
956 * In this function, we disable page faults when we're holding the
957 * inode glock while doing I/O. If a page fault occurs, we indicate
958 * that the inode glock may be dropped, fault in the pages manually,
959 * and retry.
960 */
961
962 if (iocb->ki_flags & IOCB_DIRECT)
963 return gfs2_file_direct_read(iocb, to, gh: &gh);
964
965 pagefault_disable();
966 iocb->ki_flags |= IOCB_NOIO;
967 ret = generic_file_read_iter(iocb, to);
968 iocb->ki_flags &= ~IOCB_NOIO;
969 pagefault_enable();
970 if (ret >= 0) {
971 if (!iov_iter_count(i: to))
972 return ret;
973 read = ret;
974 } else if (ret != -EFAULT) {
975 if (ret != -EAGAIN)
976 return ret;
977 if (iocb->ki_flags & IOCB_NOWAIT)
978 return ret;
979 }
980 ip = GFS2_I(inode: iocb->ki_filp->f_mapping->host);
981 gfs2_holder_init(gl: ip->i_gl, LM_ST_SHARED, flags: 0, gh: &gh);
982retry:
983 ret = gfs2_glock_nq(gh: &gh);
984 if (ret)
985 goto out_uninit;
986 pagefault_disable();
987 ret = generic_file_read_iter(iocb, to);
988 pagefault_enable();
989 if (ret <= 0 && ret != -EFAULT)
990 goto out_unlock;
991 if (ret > 0)
992 read += ret;
993
994 if (should_fault_in_pages(i: to, iocb, prev_count: &prev_count, window_size: &window_size)) {
995 gfs2_glock_dq(gh: &gh);
996 window_size -= fault_in_iov_iter_writeable(i: to, bytes: window_size);
997 if (window_size)
998 goto retry;
999 }
1000out_unlock:
1001 if (gfs2_holder_queued(gh: &gh))
1002 gfs2_glock_dq(gh: &gh);
1003out_uninit:
1004 gfs2_holder_uninit(gh: &gh);
1005 return read ? read : ret;
1006}
1007
1008static ssize_t gfs2_file_buffered_write(struct kiocb *iocb,
1009 struct iov_iter *from,
1010 struct gfs2_holder *gh)
1011{
1012 struct file *file = iocb->ki_filp;
1013 struct inode *inode = file_inode(f: file);
1014 struct gfs2_inode *ip = GFS2_I(inode);
1015 struct gfs2_sbd *sdp = GFS2_SB(inode);
1016 struct gfs2_holder *statfs_gh = NULL;
1017 size_t prev_count = 0, window_size = 0;
1018 size_t orig_count = iov_iter_count(i: from);
1019 size_t written = 0;
1020 ssize_t ret;
1021
1022 /*
1023 * In this function, we disable page faults when we're holding the
1024 * inode glock while doing I/O. If a page fault occurs, we indicate
1025 * that the inode glock may be dropped, fault in the pages manually,
1026 * and retry.
1027 */
1028
1029 if (inode == sdp->sd_rindex) {
1030 statfs_gh = kmalloc(size: sizeof(*statfs_gh), GFP_NOFS);
1031 if (!statfs_gh)
1032 return -ENOMEM;
1033 }
1034
1035 gfs2_holder_init(gl: ip->i_gl, LM_ST_EXCLUSIVE, flags: 0, gh);
1036 if (should_fault_in_pages(i: from, iocb, prev_count: &prev_count, window_size: &window_size)) {
1037retry:
1038 window_size -= fault_in_iov_iter_readable(i: from, bytes: window_size);
1039 if (!window_size) {
1040 ret = -EFAULT;
1041 goto out_uninit;
1042 }
1043 from->count = min(from->count, window_size);
1044 }
1045 ret = gfs2_glock_nq(gh);
1046 if (ret)
1047 goto out_uninit;
1048
1049 if (inode == sdp->sd_rindex) {
1050 struct gfs2_inode *m_ip = GFS2_I(inode: sdp->sd_statfs_inode);
1051
1052 ret = gfs2_glock_nq_init(gl: m_ip->i_gl, LM_ST_EXCLUSIVE,
1053 GL_NOCACHE, gh: statfs_gh);
1054 if (ret)
1055 goto out_unlock;
1056 }
1057
1058 pagefault_disable();
1059 ret = iomap_file_buffered_write(iocb, from, ops: &gfs2_iomap_ops);
1060 pagefault_enable();
1061 if (ret > 0)
1062 written += ret;
1063
1064 if (inode == sdp->sd_rindex)
1065 gfs2_glock_dq_uninit(gh: statfs_gh);
1066
1067 if (ret <= 0 && ret != -EFAULT)
1068 goto out_unlock;
1069
1070 from->count = orig_count - written;
1071 if (should_fault_in_pages(i: from, iocb, prev_count: &prev_count, window_size: &window_size)) {
1072 gfs2_glock_dq(gh);
1073 goto retry;
1074 }
1075out_unlock:
1076 if (gfs2_holder_queued(gh))
1077 gfs2_glock_dq(gh);
1078out_uninit:
1079 gfs2_holder_uninit(gh);
1080 kfree(objp: statfs_gh);
1081 from->count = orig_count - written;
1082 return written ? written : ret;
1083}
1084
1085/**
1086 * gfs2_file_write_iter - Perform a write to a file
1087 * @iocb: The io context
1088 * @from: The data to write
1089 *
1090 * We have to do a lock/unlock here to refresh the inode size for
1091 * O_APPEND writes, otherwise we can land up writing at the wrong
1092 * offset. There is still a race, but provided the app is using its
1093 * own file locking, this will make O_APPEND work as expected.
1094 *
1095 */
1096
1097static ssize_t gfs2_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
1098{
1099 struct file *file = iocb->ki_filp;
1100 struct inode *inode = file_inode(f: file);
1101 struct gfs2_inode *ip = GFS2_I(inode);
1102 struct gfs2_holder gh;
1103 ssize_t ret;
1104
1105 gfs2_size_hint(filep: file, offset: iocb->ki_pos, size: iov_iter_count(i: from));
1106
1107 if (iocb->ki_flags & IOCB_APPEND) {
1108 ret = gfs2_glock_nq_init(gl: ip->i_gl, LM_ST_SHARED, flags: 0, gh: &gh);
1109 if (ret)
1110 return ret;
1111 gfs2_glock_dq_uninit(gh: &gh);
1112 }
1113
1114 inode_lock(inode);
1115 ret = generic_write_checks(iocb, from);
1116 if (ret <= 0)
1117 goto out_unlock;
1118
1119 ret = file_remove_privs(file);
1120 if (ret)
1121 goto out_unlock;
1122
1123 if (iocb->ki_flags & IOCB_DIRECT) {
1124 struct address_space *mapping = file->f_mapping;
1125 ssize_t buffered, ret2;
1126
1127 /*
1128 * Note that under direct I/O, we don't allow and inode
1129 * timestamp updates, so we're not calling file_update_time()
1130 * here.
1131 */
1132
1133 ret = gfs2_file_direct_write(iocb, from, gh: &gh);
1134 if (ret < 0 || !iov_iter_count(i: from))
1135 goto out_unlock;
1136
1137 iocb->ki_flags |= IOCB_DSYNC;
1138 buffered = gfs2_file_buffered_write(iocb, from, gh: &gh);
1139 if (unlikely(buffered <= 0)) {
1140 if (!ret)
1141 ret = buffered;
1142 goto out_unlock;
1143 }
1144
1145 /*
1146 * We need to ensure that the page cache pages are written to
1147 * disk and invalidated to preserve the expected O_DIRECT
1148 * semantics. If the writeback or invalidate fails, only report
1149 * the direct I/O range as we don't know if the buffered pages
1150 * made it to disk.
1151 */
1152 ret2 = generic_write_sync(iocb, count: buffered);
1153 invalidate_mapping_pages(mapping,
1154 start: (iocb->ki_pos - buffered) >> PAGE_SHIFT,
1155 end: (iocb->ki_pos - 1) >> PAGE_SHIFT);
1156 if (!ret || ret2 > 0)
1157 ret += ret2;
1158 } else {
1159 ret = file_update_time(file);
1160 if (ret)
1161 goto out_unlock;
1162
1163 ret = gfs2_file_buffered_write(iocb, from, gh: &gh);
1164 if (likely(ret > 0))
1165 ret = generic_write_sync(iocb, count: ret);
1166 }
1167
1168out_unlock:
1169 inode_unlock(inode);
1170 return ret;
1171}
1172
1173static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len,
1174 int mode)
1175{
1176 struct super_block *sb = inode->i_sb;
1177 struct gfs2_inode *ip = GFS2_I(inode);
1178 loff_t end = offset + len;
1179 struct buffer_head *dibh;
1180 int error;
1181
1182 error = gfs2_meta_inode_buffer(ip, bhp: &dibh);
1183 if (unlikely(error))
1184 return error;
1185
1186 gfs2_trans_add_meta(gl: ip->i_gl, bh: dibh);
1187
1188 if (gfs2_is_stuffed(ip)) {
1189 error = gfs2_unstuff_dinode(ip);
1190 if (unlikely(error))
1191 goto out;
1192 }
1193
1194 while (offset < end) {
1195 struct iomap iomap = { };
1196
1197 error = gfs2_iomap_alloc(inode, pos: offset, length: end - offset, iomap: &iomap);
1198 if (error)
1199 goto out;
1200 offset = iomap.offset + iomap.length;
1201 if (!(iomap.flags & IOMAP_F_NEW))
1202 continue;
1203 error = sb_issue_zeroout(sb, block: iomap.addr >> inode->i_blkbits,
1204 nr_blocks: iomap.length >> inode->i_blkbits,
1205 GFP_NOFS);
1206 if (error) {
1207 fs_err(GFS2_SB(inode), "Failed to zero data buffers\n");
1208 goto out;
1209 }
1210 }
1211out:
1212 brelse(bh: dibh);
1213 return error;
1214}
1215
1216/**
1217 * calc_max_reserv() - Reverse of write_calc_reserv. Given a number of
1218 * blocks, determine how many bytes can be written.
1219 * @ip: The inode in question.
1220 * @len: Max cap of bytes. What we return in *len must be <= this.
1221 * @data_blocks: Compute and return the number of data blocks needed
1222 * @ind_blocks: Compute and return the number of indirect blocks needed
1223 * @max_blocks: The total blocks available to work with.
1224 *
1225 * Returns: void, but @len, @data_blocks and @ind_blocks are filled in.
1226 */
1227static void calc_max_reserv(struct gfs2_inode *ip, loff_t *len,
1228 unsigned int *data_blocks, unsigned int *ind_blocks,
1229 unsigned int max_blocks)
1230{
1231 loff_t max = *len;
1232 const struct gfs2_sbd *sdp = GFS2_SB(inode: &ip->i_inode);
1233 unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1);
1234
1235 for (tmp = max_data; tmp > sdp->sd_diptrs;) {
1236 tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
1237 max_data -= tmp;
1238 }
1239
1240 *data_blocks = max_data;
1241 *ind_blocks = max_blocks - max_data;
1242 *len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift;
1243 if (*len > max) {
1244 *len = max;
1245 gfs2_write_calc_reserv(ip, len: max, data_blocks, ind_blocks);
1246 }
1247}
1248
1249static long __gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
1250{
1251 struct inode *inode = file_inode(f: file);
1252 struct gfs2_sbd *sdp = GFS2_SB(inode);
1253 struct gfs2_inode *ip = GFS2_I(inode);
1254 struct gfs2_alloc_parms ap = {};
1255 unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
1256 loff_t bytes, max_bytes, max_blks;
1257 int error;
1258 const loff_t pos = offset;
1259 const loff_t count = len;
1260 loff_t bsize_mask = ~((loff_t)sdp->sd_sb.sb_bsize - 1);
1261 loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift;
1262 loff_t max_chunk_size = UINT_MAX & bsize_mask;
1263
1264 next = (next + 1) << sdp->sd_sb.sb_bsize_shift;
1265
1266 offset &= bsize_mask;
1267
1268 len = next - offset;
1269 bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2;
1270 if (!bytes)
1271 bytes = UINT_MAX;
1272 bytes &= bsize_mask;
1273 if (bytes == 0)
1274 bytes = sdp->sd_sb.sb_bsize;
1275
1276 gfs2_size_hint(filep: file, offset, size: len);
1277
1278 gfs2_write_calc_reserv(ip, PAGE_SIZE, data_blocks: &data_blocks, ind_blocks: &ind_blocks);
1279 ap.min_target = data_blocks + ind_blocks;
1280
1281 while (len > 0) {
1282 if (len < bytes)
1283 bytes = len;
1284 if (!gfs2_write_alloc_required(ip, offset, len: bytes)) {
1285 len -= bytes;
1286 offset += bytes;
1287 continue;
1288 }
1289
1290 /* We need to determine how many bytes we can actually
1291 * fallocate without exceeding quota or going over the
1292 * end of the fs. We start off optimistically by assuming
1293 * we can write max_bytes */
1294 max_bytes = (len > max_chunk_size) ? max_chunk_size : len;
1295
1296 /* Since max_bytes is most likely a theoretical max, we
1297 * calculate a more realistic 'bytes' to serve as a good
1298 * starting point for the number of bytes we may be able
1299 * to write */
1300 gfs2_write_calc_reserv(ip, len: bytes, data_blocks: &data_blocks, ind_blocks: &ind_blocks);
1301 ap.target = data_blocks + ind_blocks;
1302
1303 error = gfs2_quota_lock_check(ip, ap: &ap);
1304 if (error)
1305 return error;
1306 /* ap.allowed tells us how many blocks quota will allow
1307 * us to write. Check if this reduces max_blks */
1308 max_blks = UINT_MAX;
1309 if (ap.allowed)
1310 max_blks = ap.allowed;
1311
1312 error = gfs2_inplace_reserve(ip, ap: &ap);
1313 if (error)
1314 goto out_qunlock;
1315
1316 /* check if the selected rgrp limits our max_blks further */
1317 if (ip->i_res.rs_reserved < max_blks)
1318 max_blks = ip->i_res.rs_reserved;
1319
1320 /* Almost done. Calculate bytes that can be written using
1321 * max_blks. We also recompute max_bytes, data_blocks and
1322 * ind_blocks */
1323 calc_max_reserv(ip, len: &max_bytes, data_blocks: &data_blocks,
1324 ind_blocks: &ind_blocks, max_blocks: max_blks);
1325
1326 rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA +
1327 RES_RG_HDR + gfs2_rg_blocks(ip, requested: data_blocks + ind_blocks);
1328 if (gfs2_is_jdata(ip))
1329 rblocks += data_blocks ? data_blocks : 1;
1330
1331 error = gfs2_trans_begin(sdp, blocks: rblocks,
1332 PAGE_SIZE >> inode->i_blkbits);
1333 if (error)
1334 goto out_trans_fail;
1335
1336 error = fallocate_chunk(inode, offset, len: max_bytes, mode);
1337 gfs2_trans_end(sdp);
1338
1339 if (error)
1340 goto out_trans_fail;
1341
1342 len -= max_bytes;
1343 offset += max_bytes;
1344 gfs2_inplace_release(ip);
1345 gfs2_quota_unlock(ip);
1346 }
1347
1348 if (!(mode & FALLOC_FL_KEEP_SIZE) && (pos + count) > inode->i_size)
1349 i_size_write(inode, i_size: pos + count);
1350 file_update_time(file);
1351 mark_inode_dirty(inode);
1352
1353 if ((file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host))
1354 return vfs_fsync_range(file, start: pos, end: pos + count - 1,
1355 datasync: (file->f_flags & __O_SYNC) ? 0 : 1);
1356 return 0;
1357
1358out_trans_fail:
1359 gfs2_inplace_release(ip);
1360out_qunlock:
1361 gfs2_quota_unlock(ip);
1362 return error;
1363}
1364
1365static long gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
1366{
1367 struct inode *inode = file_inode(f: file);
1368 struct gfs2_sbd *sdp = GFS2_SB(inode);
1369 struct gfs2_inode *ip = GFS2_I(inode);
1370 struct gfs2_holder gh;
1371 int ret;
1372
1373 if (mode & ~(FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE))
1374 return -EOPNOTSUPP;
1375 /* fallocate is needed by gfs2_grow to reserve space in the rindex */
1376 if (gfs2_is_jdata(ip) && inode != sdp->sd_rindex)
1377 return -EOPNOTSUPP;
1378
1379 inode_lock(inode);
1380
1381 gfs2_holder_init(gl: ip->i_gl, LM_ST_EXCLUSIVE, flags: 0, gh: &gh);
1382 ret = gfs2_glock_nq(gh: &gh);
1383 if (ret)
1384 goto out_uninit;
1385
1386 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
1387 (offset + len) > inode->i_size) {
1388 ret = inode_newsize_ok(inode, offset: offset + len);
1389 if (ret)
1390 goto out_unlock;
1391 }
1392
1393 ret = get_write_access(inode);
1394 if (ret)
1395 goto out_unlock;
1396
1397 if (mode & FALLOC_FL_PUNCH_HOLE) {
1398 ret = __gfs2_punch_hole(file, offset, length: len);
1399 } else {
1400 ret = __gfs2_fallocate(file, mode, offset, len);
1401 if (ret)
1402 gfs2_rs_deltree(rs: &ip->i_res);
1403 }
1404
1405 put_write_access(inode);
1406out_unlock:
1407 gfs2_glock_dq(gh: &gh);
1408out_uninit:
1409 gfs2_holder_uninit(gh: &gh);
1410 inode_unlock(inode);
1411 return ret;
1412}
1413
1414static ssize_t gfs2_file_splice_write(struct pipe_inode_info *pipe,
1415 struct file *out, loff_t *ppos,
1416 size_t len, unsigned int flags)
1417{
1418 ssize_t ret;
1419
1420 gfs2_size_hint(filep: out, offset: *ppos, size: len);
1421
1422 ret = iter_file_splice_write(pipe, out, ppos, len, flags);
1423 return ret;
1424}
1425
1426#ifdef CONFIG_GFS2_FS_LOCKING_DLM
1427
1428/**
1429 * gfs2_lock - acquire/release a posix lock on a file
1430 * @file: the file pointer
1431 * @cmd: either modify or retrieve lock state, possibly wait
1432 * @fl: type and range of lock
1433 *
1434 * Returns: errno
1435 */
1436
1437static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
1438{
1439 struct gfs2_inode *ip = GFS2_I(inode: file->f_mapping->host);
1440 struct gfs2_sbd *sdp = GFS2_SB(inode: file->f_mapping->host);
1441 struct lm_lockstruct *ls = &sdp->sd_lockstruct;
1442
1443 if (!(fl->c.flc_flags & FL_POSIX))
1444 return -ENOLCK;
1445 if (gfs2_withdrawing_or_withdrawn(sdp)) {
1446 if (lock_is_unlock(fl))
1447 locks_lock_file_wait(filp: file, fl);
1448 return -EIO;
1449 }
1450 if (cmd == F_CANCELLK)
1451 return dlm_posix_cancel(lockspace: ls->ls_dlm, number: ip->i_no_addr, file, fl);
1452 else if (IS_GETLK(cmd))
1453 return dlm_posix_get(lockspace: ls->ls_dlm, number: ip->i_no_addr, file, fl);
1454 else if (lock_is_unlock(fl))
1455 return dlm_posix_unlock(lockspace: ls->ls_dlm, number: ip->i_no_addr, file, fl);
1456 else
1457 return dlm_posix_lock(lockspace: ls->ls_dlm, number: ip->i_no_addr, file, cmd, fl);
1458}
1459
1460static void __flock_holder_uninit(struct file *file, struct gfs2_holder *fl_gh)
1461{
1462 struct gfs2_glock *gl = gfs2_glock_hold(gl: fl_gh->gh_gl);
1463
1464 /*
1465 * Make sure gfs2_glock_put() won't sleep under the file->f_lock
1466 * spinlock.
1467 */
1468
1469 spin_lock(lock: &file->f_lock);
1470 gfs2_holder_uninit(gh: fl_gh);
1471 spin_unlock(lock: &file->f_lock);
1472 gfs2_glock_put(gl);
1473}
1474
1475static int do_flock(struct file *file, int cmd, struct file_lock *fl)
1476{
1477 struct gfs2_file *fp = file->private_data;
1478 struct gfs2_holder *fl_gh = &fp->f_fl_gh;
1479 struct gfs2_inode *ip = GFS2_I(inode: file_inode(f: file));
1480 struct gfs2_glock *gl;
1481 unsigned int state;
1482 u16 flags;
1483 int error = 0;
1484 int sleeptime;
1485
1486 state = lock_is_write(fl) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
1487 flags = GL_EXACT | GL_NOPID;
1488 if (!IS_SETLKW(cmd))
1489 flags |= LM_FLAG_TRY_1CB;
1490
1491 mutex_lock(&fp->f_fl_mutex);
1492
1493 if (gfs2_holder_initialized(gh: fl_gh)) {
1494 struct file_lock request;
1495 if (fl_gh->gh_state == state)
1496 goto out;
1497 locks_init_lock(&request);
1498 request.c.flc_type = F_UNLCK;
1499 request.c.flc_flags = FL_FLOCK;
1500 locks_lock_file_wait(filp: file, fl: &request);
1501 gfs2_glock_dq(gh: fl_gh);
1502 gfs2_holder_reinit(state, flags, gh: fl_gh);
1503 } else {
1504 error = gfs2_glock_get(sdp: GFS2_SB(inode: &ip->i_inode), number: ip->i_no_addr,
1505 glops: &gfs2_flock_glops, create: CREATE, glp: &gl);
1506 if (error)
1507 goto out;
1508 spin_lock(lock: &file->f_lock);
1509 gfs2_holder_init(gl, state, flags, gh: fl_gh);
1510 spin_unlock(lock: &file->f_lock);
1511 gfs2_glock_put(gl);
1512 }
1513 for (sleeptime = 1; sleeptime <= 4; sleeptime <<= 1) {
1514 error = gfs2_glock_nq(gh: fl_gh);
1515 if (error != GLR_TRYFAILED)
1516 break;
1517 fl_gh->gh_flags &= ~LM_FLAG_TRY_1CB;
1518 fl_gh->gh_flags |= LM_FLAG_TRY;
1519 msleep(msecs: sleeptime);
1520 }
1521 if (error) {
1522 __flock_holder_uninit(file, fl_gh);
1523 if (error == GLR_TRYFAILED)
1524 error = -EAGAIN;
1525 } else {
1526 error = locks_lock_file_wait(filp: file, fl);
1527 gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error);
1528 }
1529
1530out:
1531 mutex_unlock(lock: &fp->f_fl_mutex);
1532 return error;
1533}
1534
1535static void do_unflock(struct file *file, struct file_lock *fl)
1536{
1537 struct gfs2_file *fp = file->private_data;
1538 struct gfs2_holder *fl_gh = &fp->f_fl_gh;
1539
1540 mutex_lock(&fp->f_fl_mutex);
1541 locks_lock_file_wait(filp: file, fl);
1542 if (gfs2_holder_initialized(gh: fl_gh)) {
1543 gfs2_glock_dq(gh: fl_gh);
1544 __flock_holder_uninit(file, fl_gh);
1545 }
1546 mutex_unlock(lock: &fp->f_fl_mutex);
1547}
1548
1549/**
1550 * gfs2_flock - acquire/release a flock lock on a file
1551 * @file: the file pointer
1552 * @cmd: either modify or retrieve lock state, possibly wait
1553 * @fl: type and range of lock
1554 *
1555 * Returns: errno
1556 */
1557
1558static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl)
1559{
1560 if (!(fl->c.flc_flags & FL_FLOCK))
1561 return -ENOLCK;
1562
1563 if (lock_is_unlock(fl)) {
1564 do_unflock(file, fl);
1565 return 0;
1566 } else {
1567 return do_flock(file, cmd, fl);
1568 }
1569}
1570
1571const struct file_operations gfs2_file_fops = {
1572 .llseek = gfs2_llseek,
1573 .read_iter = gfs2_file_read_iter,
1574 .write_iter = gfs2_file_write_iter,
1575 .iopoll = iocb_bio_iopoll,
1576 .unlocked_ioctl = gfs2_ioctl,
1577 .compat_ioctl = gfs2_compat_ioctl,
1578 .mmap = gfs2_mmap,
1579 .open = gfs2_open,
1580 .release = gfs2_release,
1581 .fsync = gfs2_fsync,
1582 .lock = gfs2_lock,
1583 .flock = gfs2_flock,
1584 .splice_read = copy_splice_read,
1585 .splice_write = gfs2_file_splice_write,
1586 .setlease = simple_nosetlease,
1587 .fallocate = gfs2_fallocate,
1588};
1589
1590const struct file_operations gfs2_dir_fops = {
1591 .iterate_shared = gfs2_readdir,
1592 .unlocked_ioctl = gfs2_ioctl,
1593 .compat_ioctl = gfs2_compat_ioctl,
1594 .open = gfs2_open,
1595 .release = gfs2_release,
1596 .fsync = gfs2_fsync,
1597 .lock = gfs2_lock,
1598 .flock = gfs2_flock,
1599 .llseek = default_llseek,
1600};
1601
1602#endif /* CONFIG_GFS2_FS_LOCKING_DLM */
1603
1604const struct file_operations gfs2_file_fops_nolock = {
1605 .llseek = gfs2_llseek,
1606 .read_iter = gfs2_file_read_iter,
1607 .write_iter = gfs2_file_write_iter,
1608 .iopoll = iocb_bio_iopoll,
1609 .unlocked_ioctl = gfs2_ioctl,
1610 .compat_ioctl = gfs2_compat_ioctl,
1611 .mmap = gfs2_mmap,
1612 .open = gfs2_open,
1613 .release = gfs2_release,
1614 .fsync = gfs2_fsync,
1615 .splice_read = copy_splice_read,
1616 .splice_write = gfs2_file_splice_write,
1617 .setlease = generic_setlease,
1618 .fallocate = gfs2_fallocate,
1619};
1620
1621const struct file_operations gfs2_dir_fops_nolock = {
1622 .iterate_shared = gfs2_readdir,
1623 .unlocked_ioctl = gfs2_ioctl,
1624 .compat_ioctl = gfs2_compat_ioctl,
1625 .open = gfs2_open,
1626 .release = gfs2_release,
1627 .fsync = gfs2_fsync,
1628 .llseek = default_llseek,
1629};
1630
1631

source code of linux/fs/gfs2/file.c