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Linux/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/completion.h>
 10 #include <linux/buffer_head.h>
 11 #include <linux/pagemap.h>
 12 #include <linux/uio.h>
 13 #include <linux/blkdev.h>
 14 #include <linux/mm.h>
 15 #include <linux/mount.h>
 16 #include <linux/fs.h>
 17 #include <linux/gfs2_ondisk.h>
 18 #include <linux/falloc.h>
 19 #include <linux/swap.h>
 20 #include <linux/crc32.h>
 21 #include <linux/writeback.h>
 22 #include <linux/uaccess.h>
 23 #include <linux/dlm.h>
 24 #include <linux/dlm_plock.h>
 25 #include <linux/delay.h>
 26 #include <linux/backing-dev.h>
 27 
 28 #include "gfs2.h"
 29 #include "incore.h"
 30 #include "bmap.h"
 31 #include "aops.h"
 32 #include "dir.h"
 33 #include "glock.h"
 34 #include "glops.h"
 35 #include "inode.h"
 36 #include "log.h"
 37 #include "meta_io.h"
 38 #include "quota.h"
 39 #include "rgrp.h"
 40 #include "trans.h"
 41 #include "util.h"
 42 
 43 /**
 44  * gfs2_llseek - seek to a location in a file
 45  * @file: the file
 46  * @offset: the offset
 47  * @whence: Where to seek from (SEEK_SET, SEEK_CUR, or SEEK_END)
 48  *
 49  * SEEK_END requires the glock for the file because it references the
 50  * file's size.
 51  *
 52  * Returns: The new offset, or errno
 53  */
 54 
 55 static loff_t gfs2_llseek(struct file *file, loff_t offset, int whence)
 56 {
 57         struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
 58         struct gfs2_holder i_gh;
 59         loff_t error;
 60 
 61         switch (whence) {
 62         case SEEK_END:
 63                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
 64                                            &i_gh);
 65                 if (!error) {
 66                         error = generic_file_llseek(file, offset, whence);
 67                         gfs2_glock_dq_uninit(&i_gh);
 68                 }
 69                 break;
 70 
 71         case SEEK_DATA:
 72                 error = gfs2_seek_data(file, offset);
 73                 break;
 74 
 75         case SEEK_HOLE:
 76                 error = gfs2_seek_hole(file, offset);
 77                 break;
 78 
 79         case SEEK_CUR:
 80         case SEEK_SET:
 81                 /*
 82                  * These don't reference inode->i_size and don't depend on the
 83                  * block mapping, so we don't need the glock.
 84                  */
 85                 error = generic_file_llseek(file, offset, whence);
 86                 break;
 87         default:
 88                 error = -EINVAL;
 89         }
 90 
 91         return error;
 92 }
 93 
 94 /**
 95  * gfs2_readdir - Iterator for a directory
 96  * @file: The directory to read from
 97  * @ctx: What to feed directory entries to
 98  *
 99  * Returns: errno
100  */
101 
102 static int gfs2_readdir(struct file *file, struct dir_context *ctx)
103 {
104         struct inode *dir = file->f_mapping->host;
105         struct gfs2_inode *dip = GFS2_I(dir);
106         struct gfs2_holder d_gh;
107         int error;
108 
109         error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
110         if (error)
111                 return error;
112 
113         error = gfs2_dir_read(dir, ctx, &file->f_ra);
114 
115         gfs2_glock_dq_uninit(&d_gh);
116 
117         return error;
118 }
119 
120 /**
121  * fsflag_gfs2flag
122  *
123  * The FS_JOURNAL_DATA_FL flag maps to GFS2_DIF_INHERIT_JDATA for directories,
124  * and to GFS2_DIF_JDATA for non-directories.
125  */
126 static struct {
127         u32 fsflag;
128         u32 gfsflag;
129 } fsflag_gfs2flag[] = {
130         {FS_SYNC_FL, GFS2_DIF_SYNC},
131         {FS_IMMUTABLE_FL, GFS2_DIF_IMMUTABLE},
132         {FS_APPEND_FL, GFS2_DIF_APPENDONLY},
133         {FS_NOATIME_FL, GFS2_DIF_NOATIME},
134         {FS_INDEX_FL, GFS2_DIF_EXHASH},
135         {FS_TOPDIR_FL, GFS2_DIF_TOPDIR},
136         {FS_JOURNAL_DATA_FL, GFS2_DIF_JDATA | GFS2_DIF_INHERIT_JDATA},
137 };
138 
139 static int gfs2_get_flags(struct file *filp, u32 __user *ptr)
140 {
141         struct inode *inode = file_inode(filp);
142         struct gfs2_inode *ip = GFS2_I(inode);
143         struct gfs2_holder gh;
144         int i, error;
145         u32 gfsflags, fsflags = 0;
146 
147         gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
148         error = gfs2_glock_nq(&gh);
149         if (error)
150                 goto out_uninit;
151 
152         gfsflags = ip->i_diskflags;
153         if (S_ISDIR(inode->i_mode))
154                 gfsflags &= ~GFS2_DIF_JDATA;
155         else
156                 gfsflags &= ~GFS2_DIF_INHERIT_JDATA;
157         for (i = 0; i < ARRAY_SIZE(fsflag_gfs2flag); i++)
158                 if (gfsflags & fsflag_gfs2flag[i].gfsflag)
159                         fsflags |= fsflag_gfs2flag[i].fsflag;
160 
161         if (put_user(fsflags, ptr))
162                 error = -EFAULT;
163 
164         gfs2_glock_dq(&gh);
165 out_uninit:
166         gfs2_holder_uninit(&gh);
167         return error;
168 }
169 
170 void gfs2_set_inode_flags(struct inode *inode)
171 {
172         struct gfs2_inode *ip = GFS2_I(inode);
173         unsigned int flags = inode->i_flags;
174 
175         flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC|S_NOSEC);
176         if ((ip->i_eattr == 0) && !is_sxid(inode->i_mode))
177                 flags |= S_NOSEC;
178         if (ip->i_diskflags & GFS2_DIF_IMMUTABLE)
179                 flags |= S_IMMUTABLE;
180         if (ip->i_diskflags & GFS2_DIF_APPENDONLY)
181                 flags |= S_APPEND;
182         if (ip->i_diskflags & GFS2_DIF_NOATIME)
183                 flags |= S_NOATIME;
184         if (ip->i_diskflags & GFS2_DIF_SYNC)
185                 flags |= S_SYNC;
186         inode->i_flags = flags;
187 }
188 
189 /* Flags that can be set by user space */
190 #define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA|                    \
191                              GFS2_DIF_IMMUTABLE|                \
192                              GFS2_DIF_APPENDONLY|               \
193                              GFS2_DIF_NOATIME|                  \
194                              GFS2_DIF_SYNC|                     \
195                              GFS2_DIF_TOPDIR|                   \
196                              GFS2_DIF_INHERIT_JDATA)
197 
198 /**
199  * do_gfs2_set_flags - set flags on an inode
200  * @filp: file pointer
201  * @reqflags: The flags to set
202  * @mask: Indicates which flags are valid
203  *
204  */
205 static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask)
206 {
207         struct inode *inode = file_inode(filp);
208         struct gfs2_inode *ip = GFS2_I(inode);
209         struct gfs2_sbd *sdp = GFS2_SB(inode);
210         struct buffer_head *bh;
211         struct gfs2_holder gh;
212         int error;
213         u32 new_flags, flags;
214 
215         error = mnt_want_write_file(filp);
216         if (error)
217                 return error;
218 
219         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
220         if (error)
221                 goto out_drop_write;
222 
223         error = -EACCES;
224         if (!inode_owner_or_capable(inode))
225                 goto out;
226 
227         error = 0;
228         flags = ip->i_diskflags;
229         new_flags = (flags & ~mask) | (reqflags & mask);
230         if ((new_flags ^ flags) == 0)
231                 goto out;
232 
233         error = -EPERM;
234         if (IS_IMMUTABLE(inode) && (new_flags & GFS2_DIF_IMMUTABLE))
235                 goto out;
236         if (IS_APPEND(inode) && (new_flags & GFS2_DIF_APPENDONLY))
237                 goto out;
238         if (((new_flags ^ flags) & GFS2_DIF_IMMUTABLE) &&
239             !capable(CAP_LINUX_IMMUTABLE))
240                 goto out;
241         if (!IS_IMMUTABLE(inode)) {
242                 error = gfs2_permission(inode, MAY_WRITE);
243                 if (error)
244                         goto out;
245         }
246         if ((flags ^ new_flags) & GFS2_DIF_JDATA) {
247                 if (new_flags & GFS2_DIF_JDATA)
248                         gfs2_log_flush(sdp, ip->i_gl,
249                                        GFS2_LOG_HEAD_FLUSH_NORMAL |
250                                        GFS2_LFC_SET_FLAGS);
251                 error = filemap_fdatawrite(inode->i_mapping);
252                 if (error)
253                         goto out;
254                 error = filemap_fdatawait(inode->i_mapping);
255                 if (error)
256                         goto out;
257                 if (new_flags & GFS2_DIF_JDATA)
258                         gfs2_ordered_del_inode(ip);
259         }
260         error = gfs2_trans_begin(sdp, RES_DINODE, 0);
261         if (error)
262                 goto out;
263         error = gfs2_meta_inode_buffer(ip, &bh);
264         if (error)
265                 goto out_trans_end;
266         inode->i_ctime = current_time(inode);
267         gfs2_trans_add_meta(ip->i_gl, bh);
268         ip->i_diskflags = new_flags;
269         gfs2_dinode_out(ip, bh->b_data);
270         brelse(bh);
271         gfs2_set_inode_flags(inode);
272         gfs2_set_aops(inode);
273 out_trans_end:
274         gfs2_trans_end(sdp);
275 out:
276         gfs2_glock_dq_uninit(&gh);
277 out_drop_write:
278         mnt_drop_write_file(filp);
279         return error;
280 }
281 
282 static int gfs2_set_flags(struct file *filp, u32 __user *ptr)
283 {
284         struct inode *inode = file_inode(filp);
285         u32 fsflags, gfsflags = 0;
286         u32 mask;
287         int i;
288 
289         if (get_user(fsflags, ptr))
290                 return -EFAULT;
291 
292         for (i = 0; i < ARRAY_SIZE(fsflag_gfs2flag); i++) {
293                 if (fsflags & fsflag_gfs2flag[i].fsflag) {
294                         fsflags &= ~fsflag_gfs2flag[i].fsflag;
295                         gfsflags |= fsflag_gfs2flag[i].gfsflag;
296                 }
297         }
298         if (fsflags || gfsflags & ~GFS2_FLAGS_USER_SET)
299                 return -EINVAL;
300 
301         mask = GFS2_FLAGS_USER_SET;
302         if (S_ISDIR(inode->i_mode)) {
303                 mask &= ~GFS2_DIF_JDATA;
304         } else {
305                 /* The GFS2_DIF_TOPDIR flag is only valid for directories. */
306                 if (gfsflags & GFS2_DIF_TOPDIR)
307                         return -EINVAL;
308                 mask &= ~(GFS2_DIF_TOPDIR | GFS2_DIF_INHERIT_JDATA);
309         }
310 
311         return do_gfs2_set_flags(filp, gfsflags, mask);
312 }
313 
314 static int gfs2_getlabel(struct file *filp, char __user *label)
315 {
316         struct inode *inode = file_inode(filp);
317         struct gfs2_sbd *sdp = GFS2_SB(inode);
318 
319         if (copy_to_user(label, sdp->sd_sb.sb_locktable, GFS2_LOCKNAME_LEN))
320                 return -EFAULT;
321 
322         return 0;
323 }
324 
325 static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
326 {
327         switch(cmd) {
328         case FS_IOC_GETFLAGS:
329                 return gfs2_get_flags(filp, (u32 __user *)arg);
330         case FS_IOC_SETFLAGS:
331                 return gfs2_set_flags(filp, (u32 __user *)arg);
332         case FITRIM:
333                 return gfs2_fitrim(filp, (void __user *)arg);
334         case FS_IOC_GETFSLABEL:
335                 return gfs2_getlabel(filp, (char __user *)arg);
336         }
337 
338         return -ENOTTY;
339 }
340 
341 /**
342  * gfs2_size_hint - Give a hint to the size of a write request
343  * @filep: The struct file
344  * @offset: The file offset of the write
345  * @size: The length of the write
346  *
347  * When we are about to do a write, this function records the total
348  * write size in order to provide a suitable hint to the lower layers
349  * about how many blocks will be required.
350  *
351  */
352 
353 static void gfs2_size_hint(struct file *filep, loff_t offset, size_t size)
354 {
355         struct inode *inode = file_inode(filep);
356         struct gfs2_sbd *sdp = GFS2_SB(inode);
357         struct gfs2_inode *ip = GFS2_I(inode);
358         size_t blks = (size + sdp->sd_sb.sb_bsize - 1) >> sdp->sd_sb.sb_bsize_shift;
359         int hint = min_t(size_t, INT_MAX, blks);
360 
361         if (hint > atomic_read(&ip->i_sizehint))
362                 atomic_set(&ip->i_sizehint, hint);
363 }
364 
365 /**
366  * gfs2_allocate_page_backing - Use bmap to allocate blocks
367  * @page: The (locked) page to allocate backing for
368  *
369  * We try to allocate all the blocks required for the page in
370  * one go. This might fail for various reasons, so we keep
371  * trying until all the blocks to back this page are allocated.
372  * If some of the blocks are already allocated, thats ok too.
373  */
374 
375 static int gfs2_allocate_page_backing(struct page *page)
376 {
377         struct inode *inode = page->mapping->host;
378         struct buffer_head bh;
379         unsigned long size = PAGE_SIZE;
380         u64 lblock = page->index << (PAGE_SHIFT - inode->i_blkbits);
381 
382         do {
383                 bh.b_state = 0;
384                 bh.b_size = size;
385                 gfs2_block_map(inode, lblock, &bh, 1);
386                 if (!buffer_mapped(&bh))
387                         return -EIO;
388                 size -= bh.b_size;
389                 lblock += (bh.b_size >> inode->i_blkbits);
390         } while(size > 0);
391         return 0;
392 }
393 
394 /**
395  * gfs2_page_mkwrite - Make a shared, mmap()ed, page writable
396  * @vma: The virtual memory area
397  * @vmf: The virtual memory fault containing the page to become writable
398  *
399  * When the page becomes writable, we need to ensure that we have
400  * blocks allocated on disk to back that page.
401  */
402 
403 static vm_fault_t gfs2_page_mkwrite(struct vm_fault *vmf)
404 {
405         struct page *page = vmf->page;
406         struct inode *inode = file_inode(vmf->vma->vm_file);
407         struct gfs2_inode *ip = GFS2_I(inode);
408         struct gfs2_sbd *sdp = GFS2_SB(inode);
409         struct gfs2_alloc_parms ap = { .aflags = 0, };
410         unsigned long last_index;
411         u64 pos = page->index << PAGE_SHIFT;
412         unsigned int data_blocks, ind_blocks, rblocks;
413         struct gfs2_holder gh;
414         loff_t size;
415         int ret;
416 
417         sb_start_pagefault(inode->i_sb);
418 
419         ret = gfs2_rsqa_alloc(ip);
420         if (ret)
421                 goto out;
422 
423         gfs2_size_hint(vmf->vma->vm_file, pos, PAGE_SIZE);
424 
425         gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
426         ret = gfs2_glock_nq(&gh);
427         if (ret)
428                 goto out_uninit;
429 
430         /* Update file times before taking page lock */
431         file_update_time(vmf->vma->vm_file);
432 
433         set_bit(GLF_DIRTY, &ip->i_gl->gl_flags);
434         set_bit(GIF_SW_PAGED, &ip->i_flags);
435 
436         if (!gfs2_write_alloc_required(ip, pos, PAGE_SIZE)) {
437                 lock_page(page);
438                 if (!PageUptodate(page) || page->mapping != inode->i_mapping) {
439                         ret = -EAGAIN;
440                         unlock_page(page);
441                 }
442                 goto out_unlock;
443         }
444 
445         ret = gfs2_rindex_update(sdp);
446         if (ret)
447                 goto out_unlock;
448 
449         gfs2_write_calc_reserv(ip, PAGE_SIZE, &data_blocks, &ind_blocks);
450         ap.target = data_blocks + ind_blocks;
451         ret = gfs2_quota_lock_check(ip, &ap);
452         if (ret)
453                 goto out_unlock;
454         ret = gfs2_inplace_reserve(ip, &ap);
455         if (ret)
456                 goto out_quota_unlock;
457 
458         rblocks = RES_DINODE + ind_blocks;
459         if (gfs2_is_jdata(ip))
460                 rblocks += data_blocks ? data_blocks : 1;
461         if (ind_blocks || data_blocks) {
462                 rblocks += RES_STATFS + RES_QUOTA;
463                 rblocks += gfs2_rg_blocks(ip, data_blocks + ind_blocks);
464         }
465         ret = gfs2_trans_begin(sdp, rblocks, 0);
466         if (ret)
467                 goto out_trans_fail;
468 
469         lock_page(page);
470         ret = -EINVAL;
471         size = i_size_read(inode);
472         last_index = (size - 1) >> PAGE_SHIFT;
473         /* Check page index against inode size */
474         if (size == 0 || (page->index > last_index))
475                 goto out_trans_end;
476 
477         ret = -EAGAIN;
478         /* If truncated, we must retry the operation, we may have raced
479          * with the glock demotion code.
480          */
481         if (!PageUptodate(page) || page->mapping != inode->i_mapping)
482                 goto out_trans_end;
483 
484         /* Unstuff, if required, and allocate backing blocks for page */
485         ret = 0;
486         if (gfs2_is_stuffed(ip))
487                 ret = gfs2_unstuff_dinode(ip, page);
488         if (ret == 0)
489                 ret = gfs2_allocate_page_backing(page);
490 
491 out_trans_end:
492         if (ret)
493                 unlock_page(page);
494         gfs2_trans_end(sdp);
495 out_trans_fail:
496         gfs2_inplace_release(ip);
497 out_quota_unlock:
498         gfs2_quota_unlock(ip);
499 out_unlock:
500         gfs2_glock_dq(&gh);
501 out_uninit:
502         gfs2_holder_uninit(&gh);
503         if (ret == 0) {
504                 set_page_dirty(page);
505                 wait_for_stable_page(page);
506         }
507 out:
508         sb_end_pagefault(inode->i_sb);
509         return block_page_mkwrite_return(ret);
510 }
511 
512 static const struct vm_operations_struct gfs2_vm_ops = {
513         .fault = filemap_fault,
514         .map_pages = filemap_map_pages,
515         .page_mkwrite = gfs2_page_mkwrite,
516 };
517 
518 /**
519  * gfs2_mmap -
520  * @file: The file to map
521  * @vma: The VMA which described the mapping
522  *
523  * There is no need to get a lock here unless we should be updating
524  * atime. We ignore any locking errors since the only consequence is
525  * a missed atime update (which will just be deferred until later).
526  *
527  * Returns: 0
528  */
529 
530 static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
531 {
532         struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
533 
534         if (!(file->f_flags & O_NOATIME) &&
535             !IS_NOATIME(&ip->i_inode)) {
536                 struct gfs2_holder i_gh;
537                 int error;
538 
539                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
540                                            &i_gh);
541                 if (error)
542                         return error;
543                 /* grab lock to update inode */
544                 gfs2_glock_dq_uninit(&i_gh);
545                 file_accessed(file);
546         }
547         vma->vm_ops = &gfs2_vm_ops;
548 
549         return 0;
550 }
551 
552 /**
553  * gfs2_open_common - This is common to open and atomic_open
554  * @inode: The inode being opened
555  * @file: The file being opened
556  *
557  * This maybe called under a glock or not depending upon how it has
558  * been called. We must always be called under a glock for regular
559  * files, however. For other file types, it does not matter whether
560  * we hold the glock or not.
561  *
562  * Returns: Error code or 0 for success
563  */
564 
565 int gfs2_open_common(struct inode *inode, struct file *file)
566 {
567         struct gfs2_file *fp;
568         int ret;
569 
570         if (S_ISREG(inode->i_mode)) {
571                 ret = generic_file_open(inode, file);
572                 if (ret)
573                         return ret;
574         }
575 
576         fp = kzalloc(sizeof(struct gfs2_file), GFP_NOFS);
577         if (!fp)
578                 return -ENOMEM;
579 
580         mutex_init(&fp->f_fl_mutex);
581 
582         gfs2_assert_warn(GFS2_SB(inode), !file->private_data);
583         file->private_data = fp;
584         return 0;
585 }
586 
587 /**
588  * gfs2_open - open a file
589  * @inode: the inode to open
590  * @file: the struct file for this opening
591  *
592  * After atomic_open, this function is only used for opening files
593  * which are already cached. We must still get the glock for regular
594  * files to ensure that we have the file size uptodate for the large
595  * file check which is in the common code. That is only an issue for
596  * regular files though.
597  *
598  * Returns: errno
599  */
600 
601 static int gfs2_open(struct inode *inode, struct file *file)
602 {
603         struct gfs2_inode *ip = GFS2_I(inode);
604         struct gfs2_holder i_gh;
605         int error;
606         bool need_unlock = false;
607 
608         if (S_ISREG(ip->i_inode.i_mode)) {
609                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
610                                            &i_gh);
611                 if (error)
612                         return error;
613                 need_unlock = true;
614         }
615 
616         error = gfs2_open_common(inode, file);
617 
618         if (need_unlock)
619                 gfs2_glock_dq_uninit(&i_gh);
620 
621         return error;
622 }
623 
624 /**
625  * gfs2_release - called to close a struct file
626  * @inode: the inode the struct file belongs to
627  * @file: the struct file being closed
628  *
629  * Returns: errno
630  */
631 
632 static int gfs2_release(struct inode *inode, struct file *file)
633 {
634         struct gfs2_inode *ip = GFS2_I(inode);
635 
636         kfree(file->private_data);
637         file->private_data = NULL;
638 
639         if (!(file->f_mode & FMODE_WRITE))
640                 return 0;
641 
642         gfs2_rsqa_delete(ip, &inode->i_writecount);
643         return 0;
644 }
645 
646 /**
647  * gfs2_fsync - sync the dirty data for a file (across the cluster)
648  * @file: the file that points to the dentry
649  * @start: the start position in the file to sync
650  * @end: the end position in the file to sync
651  * @datasync: set if we can ignore timestamp changes
652  *
653  * We split the data flushing here so that we don't wait for the data
654  * until after we've also sent the metadata to disk. Note that for
655  * data=ordered, we will write & wait for the data at the log flush
656  * stage anyway, so this is unlikely to make much of a difference
657  * except in the data=writeback case.
658  *
659  * If the fdatawrite fails due to any reason except -EIO, we will
660  * continue the remainder of the fsync, although we'll still report
661  * the error at the end. This is to match filemap_write_and_wait_range()
662  * behaviour.
663  *
664  * Returns: errno
665  */
666 
667 static int gfs2_fsync(struct file *file, loff_t start, loff_t end,
668                       int datasync)
669 {
670         struct address_space *mapping = file->f_mapping;
671         struct inode *inode = mapping->host;
672         int sync_state = inode->i_state & I_DIRTY_ALL;
673         struct gfs2_inode *ip = GFS2_I(inode);
674         int ret = 0, ret1 = 0;
675 
676         if (mapping->nrpages) {
677                 ret1 = filemap_fdatawrite_range(mapping, start, end);
678                 if (ret1 == -EIO)
679                         return ret1;
680         }
681 
682         if (!gfs2_is_jdata(ip))
683                 sync_state &= ~I_DIRTY_PAGES;
684         if (datasync)
685                 sync_state &= ~(I_DIRTY_SYNC | I_DIRTY_TIME);
686 
687         if (sync_state) {
688                 ret = sync_inode_metadata(inode, 1);
689                 if (ret)
690                         return ret;
691                 if (gfs2_is_jdata(ip))
692                         ret = file_write_and_wait(file);
693                 if (ret)
694                         return ret;
695                 gfs2_ail_flush(ip->i_gl, 1);
696         }
697 
698         if (mapping->nrpages)
699                 ret = file_fdatawait_range(file, start, end);
700 
701         return ret ? ret : ret1;
702 }
703 
704 static ssize_t gfs2_file_direct_read(struct kiocb *iocb, struct iov_iter *to)
705 {
706         struct file *file = iocb->ki_filp;
707         struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
708         size_t count = iov_iter_count(to);
709         struct gfs2_holder gh;
710         ssize_t ret;
711 
712         if (!count)
713                 return 0; /* skip atime */
714 
715         gfs2_holder_init(ip->i_gl, LM_ST_DEFERRED, 0, &gh);
716         ret = gfs2_glock_nq(&gh);
717         if (ret)
718                 goto out_uninit;
719 
720         ret = iomap_dio_rw(iocb, to, &gfs2_iomap_ops, NULL);
721 
722         gfs2_glock_dq(&gh);
723 out_uninit:
724         gfs2_holder_uninit(&gh);
725         return ret;
726 }
727 
728 static ssize_t gfs2_file_direct_write(struct kiocb *iocb, struct iov_iter *from)
729 {
730         struct file *file = iocb->ki_filp;
731         struct inode *inode = file->f_mapping->host;
732         struct gfs2_inode *ip = GFS2_I(inode);
733         size_t len = iov_iter_count(from);
734         loff_t offset = iocb->ki_pos;
735         struct gfs2_holder gh;
736         ssize_t ret;
737 
738         /*
739          * Deferred lock, even if its a write, since we do no allocation on
740          * this path. All we need to change is the atime, and this lock mode
741          * ensures that other nodes have flushed their buffered read caches
742          * (i.e. their page cache entries for this inode). We do not,
743          * unfortunately, have the option of only flushing a range like the
744          * VFS does.
745          */
746         gfs2_holder_init(ip->i_gl, LM_ST_DEFERRED, 0, &gh);
747         ret = gfs2_glock_nq(&gh);
748         if (ret)
749                 goto out_uninit;
750 
751         /* Silently fall back to buffered I/O when writing beyond EOF */
752         if (offset + len > i_size_read(&ip->i_inode))
753                 goto out;
754 
755         ret = iomap_dio_rw(iocb, from, &gfs2_iomap_ops, NULL);
756 
757 out:
758         gfs2_glock_dq(&gh);
759 out_uninit:
760         gfs2_holder_uninit(&gh);
761         return ret;
762 }
763 
764 static ssize_t gfs2_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
765 {
766         ssize_t ret;
767 
768         if (iocb->ki_flags & IOCB_DIRECT) {
769                 ret = gfs2_file_direct_read(iocb, to);
770                 if (likely(ret != -ENOTBLK))
771                         return ret;
772                 iocb->ki_flags &= ~IOCB_DIRECT;
773         }
774         return generic_file_read_iter(iocb, to);
775 }
776 
777 /**
778  * gfs2_file_write_iter - Perform a write to a file
779  * @iocb: The io context
780  * @from: The data to write
781  *
782  * We have to do a lock/unlock here to refresh the inode size for
783  * O_APPEND writes, otherwise we can land up writing at the wrong
784  * offset. There is still a race, but provided the app is using its
785  * own file locking, this will make O_APPEND work as expected.
786  *
787  */
788 
789 static ssize_t gfs2_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
790 {
791         struct file *file = iocb->ki_filp;
792         struct inode *inode = file_inode(file);
793         struct gfs2_inode *ip = GFS2_I(inode);
794         ssize_t written = 0, ret;
795 
796         ret = gfs2_rsqa_alloc(ip);
797         if (ret)
798                 return ret;
799 
800         gfs2_size_hint(file, iocb->ki_pos, iov_iter_count(from));
801 
802         if (iocb->ki_flags & IOCB_APPEND) {
803                 struct gfs2_holder gh;
804 
805                 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
806                 if (ret)
807                         return ret;
808                 gfs2_glock_dq_uninit(&gh);
809         }
810 
811         inode_lock(inode);
812         ret = generic_write_checks(iocb, from);
813         if (ret <= 0)
814                 goto out;
815 
816         /* We can write back this queue in page reclaim */
817         current->backing_dev_info = inode_to_bdi(inode);
818 
819         ret = file_remove_privs(file);
820         if (ret)
821                 goto out2;
822 
823         ret = file_update_time(file);
824         if (ret)
825                 goto out2;
826 
827         if (iocb->ki_flags & IOCB_DIRECT) {
828                 struct address_space *mapping = file->f_mapping;
829                 loff_t pos, endbyte;
830                 ssize_t buffered;
831 
832                 written = gfs2_file_direct_write(iocb, from);
833                 if (written < 0 || !iov_iter_count(from))
834                         goto out2;
835 
836                 ret = iomap_file_buffered_write(iocb, from, &gfs2_iomap_ops);
837                 if (unlikely(ret < 0))
838                         goto out2;
839                 buffered = ret;
840 
841                 /*
842                  * We need to ensure that the page cache pages are written to
843                  * disk and invalidated to preserve the expected O_DIRECT
844                  * semantics.
845                  */
846                 pos = iocb->ki_pos;
847                 endbyte = pos + buffered - 1;
848                 ret = filemap_write_and_wait_range(mapping, pos, endbyte);
849                 if (!ret) {
850                         iocb->ki_pos += buffered;
851                         written += buffered;
852                         invalidate_mapping_pages(mapping,
853                                                  pos >> PAGE_SHIFT,
854                                                  endbyte >> PAGE_SHIFT);
855                 } else {
856                         /*
857                          * We don't know how much we wrote, so just return
858                          * the number of bytes which were direct-written
859                          */
860                 }
861         } else {
862                 ret = iomap_file_buffered_write(iocb, from, &gfs2_iomap_ops);
863                 if (likely(ret > 0))
864                         iocb->ki_pos += ret;
865         }
866 
867 out2:
868         current->backing_dev_info = NULL;
869 out:
870         inode_unlock(inode);
871         if (likely(ret > 0)) {
872                 /* Handle various SYNC-type writes */
873                 ret = generic_write_sync(iocb, ret);
874         }
875         return written ? written : ret;
876 }
877 
878 static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len,
879                            int mode)
880 {
881         struct super_block *sb = inode->i_sb;
882         struct gfs2_inode *ip = GFS2_I(inode);
883         loff_t end = offset + len;
884         struct buffer_head *dibh;
885         int error;
886 
887         error = gfs2_meta_inode_buffer(ip, &dibh);
888         if (unlikely(error))
889                 return error;
890 
891         gfs2_trans_add_meta(ip->i_gl, dibh);
892 
893         if (gfs2_is_stuffed(ip)) {
894                 error = gfs2_unstuff_dinode(ip, NULL);
895                 if (unlikely(error))
896                         goto out;
897         }
898 
899         while (offset < end) {
900                 struct iomap iomap = { };
901 
902                 error = gfs2_iomap_get_alloc(inode, offset, end - offset,
903                                              &iomap);
904                 if (error)
905                         goto out;
906                 offset = iomap.offset + iomap.length;
907                 if (!(iomap.flags & IOMAP_F_NEW))
908                         continue;
909                 error = sb_issue_zeroout(sb, iomap.addr >> inode->i_blkbits,
910                                          iomap.length >> inode->i_blkbits,
911                                          GFP_NOFS);
912                 if (error) {
913                         fs_err(GFS2_SB(inode), "Failed to zero data buffers\n");
914                         goto out;
915                 }
916         }
917 out:
918         brelse(dibh);
919         return error;
920 }
921 /**
922  * calc_max_reserv() - Reverse of write_calc_reserv. Given a number of
923  *                     blocks, determine how many bytes can be written.
924  * @ip:          The inode in question.
925  * @len:         Max cap of bytes. What we return in *len must be <= this.
926  * @data_blocks: Compute and return the number of data blocks needed
927  * @ind_blocks:  Compute and return the number of indirect blocks needed
928  * @max_blocks:  The total blocks available to work with.
929  *
930  * Returns: void, but @len, @data_blocks and @ind_blocks are filled in.
931  */
932 static void calc_max_reserv(struct gfs2_inode *ip, loff_t *len,
933                             unsigned int *data_blocks, unsigned int *ind_blocks,
934                             unsigned int max_blocks)
935 {
936         loff_t max = *len;
937         const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
938         unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1);
939 
940         for (tmp = max_data; tmp > sdp->sd_diptrs;) {
941                 tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
942                 max_data -= tmp;
943         }
944 
945         *data_blocks = max_data;
946         *ind_blocks = max_blocks - max_data;
947         *len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift;
948         if (*len > max) {
949                 *len = max;
950                 gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks);
951         }
952 }
953 
954 static long __gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
955 {
956         struct inode *inode = file_inode(file);
957         struct gfs2_sbd *sdp = GFS2_SB(inode);
958         struct gfs2_inode *ip = GFS2_I(inode);
959         struct gfs2_alloc_parms ap = { .aflags = 0, };
960         unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
961         loff_t bytes, max_bytes, max_blks;
962         int error;
963         const loff_t pos = offset;
964         const loff_t count = len;
965         loff_t bsize_mask = ~((loff_t)sdp->sd_sb.sb_bsize - 1);
966         loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift;
967         loff_t max_chunk_size = UINT_MAX & bsize_mask;
968 
969         next = (next + 1) << sdp->sd_sb.sb_bsize_shift;
970 
971         offset &= bsize_mask;
972 
973         len = next - offset;
974         bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2;
975         if (!bytes)
976                 bytes = UINT_MAX;
977         bytes &= bsize_mask;
978         if (bytes == 0)
979                 bytes = sdp->sd_sb.sb_bsize;
980 
981         gfs2_size_hint(file, offset, len);
982 
983         gfs2_write_calc_reserv(ip, PAGE_SIZE, &data_blocks, &ind_blocks);
984         ap.min_target = data_blocks + ind_blocks;
985 
986         while (len > 0) {
987                 if (len < bytes)
988                         bytes = len;
989                 if (!gfs2_write_alloc_required(ip, offset, bytes)) {
990                         len -= bytes;
991                         offset += bytes;
992                         continue;
993                 }
994 
995                 /* We need to determine how many bytes we can actually
996                  * fallocate without exceeding quota or going over the
997                  * end of the fs. We start off optimistically by assuming
998                  * we can write max_bytes */
999                 max_bytes = (len > max_chunk_size) ? max_chunk_size : len;
1000 
1001                 /* Since max_bytes is most likely a theoretical max, we
1002                  * calculate a more realistic 'bytes' to serve as a good
1003                  * starting point for the number of bytes we may be able
1004                  * to write */
1005                 gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks);
1006                 ap.target = data_blocks + ind_blocks;
1007 
1008                 error = gfs2_quota_lock_check(ip, &ap);
1009                 if (error)
1010                         return error;
1011                 /* ap.allowed tells us how many blocks quota will allow
1012                  * us to write. Check if this reduces max_blks */
1013                 max_blks = UINT_MAX;
1014                 if (ap.allowed)
1015                         max_blks = ap.allowed;
1016 
1017                 error = gfs2_inplace_reserve(ip, &ap);
1018                 if (error)
1019                         goto out_qunlock;
1020 
1021                 /* check if the selected rgrp limits our max_blks further */
1022                 if (ap.allowed && ap.allowed < max_blks)
1023                         max_blks = ap.allowed;
1024 
1025                 /* Almost done. Calculate bytes that can be written using
1026                  * max_blks. We also recompute max_bytes, data_blocks and
1027                  * ind_blocks */
1028                 calc_max_reserv(ip, &max_bytes, &data_blocks,
1029                                 &ind_blocks, max_blks);
1030 
1031                 rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA +
1032                           RES_RG_HDR + gfs2_rg_blocks(ip, data_blocks + ind_blocks);
1033                 if (gfs2_is_jdata(ip))
1034                         rblocks += data_blocks ? data_blocks : 1;
1035 
1036                 error = gfs2_trans_begin(sdp, rblocks,
1037                                          PAGE_SIZE/sdp->sd_sb.sb_bsize);
1038                 if (error)
1039                         goto out_trans_fail;
1040 
1041                 error = fallocate_chunk(inode, offset, max_bytes, mode);
1042                 gfs2_trans_end(sdp);
1043 
1044                 if (error)
1045                         goto out_trans_fail;
1046 
1047                 len -= max_bytes;
1048                 offset += max_bytes;
1049                 gfs2_inplace_release(ip);
1050                 gfs2_quota_unlock(ip);
1051         }
1052 
1053         if (!(mode & FALLOC_FL_KEEP_SIZE) && (pos + count) > inode->i_size) {
1054                 i_size_write(inode, pos + count);
1055                 file_update_time(file);
1056                 mark_inode_dirty(inode);
1057         }
1058 
1059         if ((file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host))
1060                 return vfs_fsync_range(file, pos, pos + count - 1,
1061                                (file->f_flags & __O_SYNC) ? 0 : 1);
1062         return 0;
1063 
1064 out_trans_fail:
1065         gfs2_inplace_release(ip);
1066 out_qunlock:
1067         gfs2_quota_unlock(ip);
1068         return error;
1069 }
1070 
1071 static long gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
1072 {
1073         struct inode *inode = file_inode(file);
1074         struct gfs2_sbd *sdp = GFS2_SB(inode);
1075         struct gfs2_inode *ip = GFS2_I(inode);
1076         struct gfs2_holder gh;
1077         int ret;
1078 
1079         if (mode & ~(FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE))
1080                 return -EOPNOTSUPP;
1081         /* fallocate is needed by gfs2_grow to reserve space in the rindex */
1082         if (gfs2_is_jdata(ip) && inode != sdp->sd_rindex)
1083                 return -EOPNOTSUPP;
1084 
1085         inode_lock(inode);
1086 
1087         gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
1088         ret = gfs2_glock_nq(&gh);
1089         if (ret)
1090                 goto out_uninit;
1091 
1092         if (!(mode & FALLOC_FL_KEEP_SIZE) &&
1093             (offset + len) > inode->i_size) {
1094                 ret = inode_newsize_ok(inode, offset + len);
1095                 if (ret)
1096                         goto out_unlock;
1097         }
1098 
1099         ret = get_write_access(inode);
1100         if (ret)
1101                 goto out_unlock;
1102 
1103         if (mode & FALLOC_FL_PUNCH_HOLE) {
1104                 ret = __gfs2_punch_hole(file, offset, len);
1105         } else {
1106                 ret = gfs2_rsqa_alloc(ip);
1107                 if (ret)
1108                         goto out_putw;
1109 
1110                 ret = __gfs2_fallocate(file, mode, offset, len);
1111 
1112                 if (ret)
1113                         gfs2_rs_deltree(&ip->i_res);
1114         }
1115 
1116 out_putw:
1117         put_write_access(inode);
1118 out_unlock:
1119         gfs2_glock_dq(&gh);
1120 out_uninit:
1121         gfs2_holder_uninit(&gh);
1122         inode_unlock(inode);
1123         return ret;
1124 }
1125 
1126 static ssize_t gfs2_file_splice_write(struct pipe_inode_info *pipe,
1127                                       struct file *out, loff_t *ppos,
1128                                       size_t len, unsigned int flags)
1129 {
1130         int error;
1131         struct gfs2_inode *ip = GFS2_I(out->f_mapping->host);
1132 
1133         error = gfs2_rsqa_alloc(ip);
1134         if (error)
1135                 return (ssize_t)error;
1136 
1137         gfs2_size_hint(out, *ppos, len);
1138 
1139         return iter_file_splice_write(pipe, out, ppos, len, flags);
1140 }
1141 
1142 #ifdef CONFIG_GFS2_FS_LOCKING_DLM
1143 
1144 /**
1145  * gfs2_lock - acquire/release a posix lock on a file
1146  * @file: the file pointer
1147  * @cmd: either modify or retrieve lock state, possibly wait
1148  * @fl: type and range of lock
1149  *
1150  * Returns: errno
1151  */
1152 
1153 static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
1154 {
1155         struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
1156         struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
1157         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
1158 
1159         if (!(fl->fl_flags & FL_POSIX))
1160                 return -ENOLCK;
1161         if (__mandatory_lock(&ip->i_inode) && fl->fl_type != F_UNLCK)
1162                 return -ENOLCK;
1163 
1164         if (cmd == F_CANCELLK) {
1165                 /* Hack: */
1166                 cmd = F_SETLK;
1167                 fl->fl_type = F_UNLCK;
1168         }
1169         if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) {
1170                 if (fl->fl_type == F_UNLCK)
1171                         locks_lock_file_wait(file, fl);
1172                 return -EIO;
1173         }
1174         if (IS_GETLK(cmd))
1175                 return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl);
1176         else if (fl->fl_type == F_UNLCK)
1177                 return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl);
1178         else
1179                 return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl);
1180 }
1181 
1182 static int do_flock(struct file *file, int cmd, struct file_lock *fl)
1183 {
1184         struct gfs2_file *fp = file->private_data;
1185         struct gfs2_holder *fl_gh = &fp->f_fl_gh;
1186         struct gfs2_inode *ip = GFS2_I(file_inode(file));
1187         struct gfs2_glock *gl;
1188         unsigned int state;
1189         u16 flags;
1190         int error = 0;
1191         int sleeptime;
1192 
1193         state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
1194         flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY_1CB) | GL_EXACT;
1195 
1196         mutex_lock(&fp->f_fl_mutex);
1197 
1198         if (gfs2_holder_initialized(fl_gh)) {
1199                 struct file_lock request;
1200                 if (fl_gh->gh_state == state)
1201                         goto out;
1202                 locks_init_lock(&request);
1203                 request.fl_type = F_UNLCK;
1204                 request.fl_flags = FL_FLOCK;
1205                 locks_lock_file_wait(file, &request);
1206                 gfs2_glock_dq(fl_gh);
1207                 gfs2_holder_reinit(state, flags, fl_gh);
1208         } else {
1209                 error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr,
1210                                        &gfs2_flock_glops, CREATE, &gl);
1211                 if (error)
1212                         goto out;
1213                 gfs2_holder_init(gl, state, flags, fl_gh);
1214                 gfs2_glock_put(gl);
1215         }
1216         for (sleeptime = 1; sleeptime <= 4; sleeptime <<= 1) {
1217                 error = gfs2_glock_nq(fl_gh);
1218                 if (error != GLR_TRYFAILED)
1219                         break;
1220                 fl_gh->gh_flags = LM_FLAG_TRY | GL_EXACT;
1221                 fl_gh->gh_error = 0;
1222                 msleep(sleeptime);
1223         }
1224         if (error) {
1225                 gfs2_holder_uninit(fl_gh);
1226                 if (error == GLR_TRYFAILED)
1227                         error = -EAGAIN;
1228         } else {
1229                 error = locks_lock_file_wait(file, fl);
1230                 gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error);
1231         }
1232 
1233 out:
1234         mutex_unlock(&fp->f_fl_mutex);
1235         return error;
1236 }
1237 
1238 static void do_unflock(struct file *file, struct file_lock *fl)
1239 {
1240         struct gfs2_file *fp = file->private_data;
1241         struct gfs2_holder *fl_gh = &fp->f_fl_gh;
1242 
1243         mutex_lock(&fp->f_fl_mutex);
1244         locks_lock_file_wait(file, fl);
1245         if (gfs2_holder_initialized(fl_gh)) {
1246                 gfs2_glock_dq(fl_gh);
1247                 gfs2_holder_uninit(fl_gh);
1248         }
1249         mutex_unlock(&fp->f_fl_mutex);
1250 }
1251 
1252 /**
1253  * gfs2_flock - acquire/release a flock lock on a file
1254  * @file: the file pointer
1255  * @cmd: either modify or retrieve lock state, possibly wait
1256  * @fl: type and range of lock
1257  *
1258  * Returns: errno
1259  */
1260 
1261 static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl)
1262 {
1263         if (!(fl->fl_flags & FL_FLOCK))
1264                 return -ENOLCK;
1265         if (fl->fl_type & LOCK_MAND)
1266                 return -EOPNOTSUPP;
1267 
1268         if (fl->fl_type == F_UNLCK) {
1269                 do_unflock(file, fl);
1270                 return 0;
1271         } else {
1272                 return do_flock(file, cmd, fl);
1273         }
1274 }
1275 
1276 const struct file_operations gfs2_file_fops = {
1277         .llseek         = gfs2_llseek,
1278         .read_iter      = gfs2_file_read_iter,
1279         .write_iter     = gfs2_file_write_iter,
1280         .iopoll         = iomap_dio_iopoll,
1281         .unlocked_ioctl = gfs2_ioctl,
1282         .mmap           = gfs2_mmap,
1283         .open           = gfs2_open,
1284         .release        = gfs2_release,
1285         .fsync          = gfs2_fsync,
1286         .lock           = gfs2_lock,
1287         .flock          = gfs2_flock,
1288         .splice_read    = generic_file_splice_read,
1289         .splice_write   = gfs2_file_splice_write,
1290         .setlease       = simple_nosetlease,
1291         .fallocate      = gfs2_fallocate,
1292 };
1293 
1294 const struct file_operations gfs2_dir_fops = {
1295         .iterate_shared = gfs2_readdir,
1296         .unlocked_ioctl = gfs2_ioctl,
1297         .open           = gfs2_open,
1298         .release        = gfs2_release,
1299         .fsync          = gfs2_fsync,
1300         .lock           = gfs2_lock,
1301         .flock          = gfs2_flock,
1302         .llseek         = default_llseek,
1303 };
1304 
1305 #endif /* CONFIG_GFS2_FS_LOCKING_DLM */
1306 
1307 const struct file_operations gfs2_file_fops_nolock = {
1308         .llseek         = gfs2_llseek,
1309         .read_iter      = gfs2_file_read_iter,
1310         .write_iter     = gfs2_file_write_iter,
1311         .iopoll         = iomap_dio_iopoll,
1312         .unlocked_ioctl = gfs2_ioctl,
1313         .mmap           = gfs2_mmap,
1314         .open           = gfs2_open,
1315         .release        = gfs2_release,
1316         .fsync          = gfs2_fsync,
1317         .splice_read    = generic_file_splice_read,
1318         .splice_write   = gfs2_file_splice_write,
1319         .setlease       = generic_setlease,
1320         .fallocate      = gfs2_fallocate,
1321 };
1322 
1323 const struct file_operations gfs2_dir_fops_nolock = {
1324         .iterate_shared = gfs2_readdir,
1325         .unlocked_ioctl = gfs2_ioctl,
1326         .open           = gfs2_open,
1327         .release        = gfs2_release,
1328         .fsync          = gfs2_fsync,
1329         .llseek         = default_llseek,
1330 };
1331 
1332 

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