Merge remote branch 'alsa/fixes' into for-linus
[deliverable/linux.git] / fs / gfs2 / file.c
1 /*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
4 *
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
7 * of the GNU General Public License version 2.
8 */
9
10 #include <linux/slab.h>
11 #include <linux/spinlock.h>
12 #include <linux/completion.h>
13 #include <linux/buffer_head.h>
14 #include <linux/pagemap.h>
15 #include <linux/uio.h>
16 #include <linux/blkdev.h>
17 #include <linux/mm.h>
18 #include <linux/mount.h>
19 #include <linux/fs.h>
20 #include <linux/gfs2_ondisk.h>
21 #include <linux/ext2_fs.h>
22 #include <linux/crc32.h>
23 #include <linux/writeback.h>
24 #include <asm/uaccess.h>
25 #include <linux/dlm.h>
26 #include <linux/dlm_plock.h>
27
28 #include "gfs2.h"
29 #include "incore.h"
30 #include "bmap.h"
31 #include "dir.h"
32 #include "glock.h"
33 #include "glops.h"
34 #include "inode.h"
35 #include "log.h"
36 #include "meta_io.h"
37 #include "quota.h"
38 #include "rgrp.h"
39 #include "trans.h"
40 #include "util.h"
41
42 /**
43 * gfs2_llseek - seek to a location in a file
44 * @file: the file
45 * @offset: the offset
46 * @origin: Where to seek from (SEEK_SET, SEEK_CUR, or SEEK_END)
47 *
48 * SEEK_END requires the glock for the file because it references the
49 * file's size.
50 *
51 * Returns: The new offset, or errno
52 */
53
54 static loff_t gfs2_llseek(struct file *file, loff_t offset, int origin)
55 {
56 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
57 struct gfs2_holder i_gh;
58 loff_t error;
59
60 if (origin == 2) {
61 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
62 &i_gh);
63 if (!error) {
64 error = generic_file_llseek_unlocked(file, offset, origin);
65 gfs2_glock_dq_uninit(&i_gh);
66 }
67 } else
68 error = generic_file_llseek_unlocked(file, offset, origin);
69
70 return error;
71 }
72
73 /**
74 * gfs2_readdir - Read directory entries from a directory
75 * @file: The directory to read from
76 * @dirent: Buffer for dirents
77 * @filldir: Function used to do the copying
78 *
79 * Returns: errno
80 */
81
82 static int gfs2_readdir(struct file *file, void *dirent, filldir_t filldir)
83 {
84 struct inode *dir = file->f_mapping->host;
85 struct gfs2_inode *dip = GFS2_I(dir);
86 struct gfs2_holder d_gh;
87 u64 offset = file->f_pos;
88 int error;
89
90 gfs2_holder_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
91 error = gfs2_glock_nq(&d_gh);
92 if (error) {
93 gfs2_holder_uninit(&d_gh);
94 return error;
95 }
96
97 error = gfs2_dir_read(dir, &offset, dirent, filldir);
98
99 gfs2_glock_dq_uninit(&d_gh);
100
101 file->f_pos = offset;
102
103 return error;
104 }
105
106 /**
107 * fsflags_cvt
108 * @table: A table of 32 u32 flags
109 * @val: a 32 bit value to convert
110 *
111 * This function can be used to convert between fsflags values and
112 * GFS2's own flags values.
113 *
114 * Returns: the converted flags
115 */
116 static u32 fsflags_cvt(const u32 *table, u32 val)
117 {
118 u32 res = 0;
119 while(val) {
120 if (val & 1)
121 res |= *table;
122 table++;
123 val >>= 1;
124 }
125 return res;
126 }
127
128 static const u32 fsflags_to_gfs2[32] = {
129 [3] = GFS2_DIF_SYNC,
130 [4] = GFS2_DIF_IMMUTABLE,
131 [5] = GFS2_DIF_APPENDONLY,
132 [7] = GFS2_DIF_NOATIME,
133 [12] = GFS2_DIF_EXHASH,
134 [14] = GFS2_DIF_INHERIT_JDATA,
135 };
136
137 static const u32 gfs2_to_fsflags[32] = {
138 [gfs2fl_Sync] = FS_SYNC_FL,
139 [gfs2fl_Immutable] = FS_IMMUTABLE_FL,
140 [gfs2fl_AppendOnly] = FS_APPEND_FL,
141 [gfs2fl_NoAtime] = FS_NOATIME_FL,
142 [gfs2fl_ExHash] = FS_INDEX_FL,
143 [gfs2fl_InheritJdata] = FS_JOURNAL_DATA_FL,
144 };
145
146 static int gfs2_get_flags(struct file *filp, u32 __user *ptr)
147 {
148 struct inode *inode = filp->f_path.dentry->d_inode;
149 struct gfs2_inode *ip = GFS2_I(inode);
150 struct gfs2_holder gh;
151 int error;
152 u32 fsflags;
153
154 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
155 error = gfs2_glock_nq(&gh);
156 if (error)
157 return error;
158
159 fsflags = fsflags_cvt(gfs2_to_fsflags, ip->i_diskflags);
160 if (!S_ISDIR(inode->i_mode) && ip->i_diskflags & GFS2_DIF_JDATA)
161 fsflags |= FS_JOURNAL_DATA_FL;
162 if (put_user(fsflags, ptr))
163 error = -EFAULT;
164
165 gfs2_glock_dq(&gh);
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);
176 if (ip->i_diskflags & GFS2_DIF_IMMUTABLE)
177 flags |= S_IMMUTABLE;
178 if (ip->i_diskflags & GFS2_DIF_APPENDONLY)
179 flags |= S_APPEND;
180 if (ip->i_diskflags & GFS2_DIF_NOATIME)
181 flags |= S_NOATIME;
182 if (ip->i_diskflags & GFS2_DIF_SYNC)
183 flags |= S_SYNC;
184 inode->i_flags = flags;
185 }
186
187 /* Flags that can be set by user space */
188 #define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA| \
189 GFS2_DIF_IMMUTABLE| \
190 GFS2_DIF_APPENDONLY| \
191 GFS2_DIF_NOATIME| \
192 GFS2_DIF_SYNC| \
193 GFS2_DIF_SYSTEM| \
194 GFS2_DIF_INHERIT_JDATA)
195
196 /**
197 * gfs2_set_flags - set flags on an inode
198 * @inode: The inode
199 * @flags: The flags to set
200 * @mask: Indicates which flags are valid
201 *
202 */
203 static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask)
204 {
205 struct inode *inode = filp->f_path.dentry->d_inode;
206 struct gfs2_inode *ip = GFS2_I(inode);
207 struct gfs2_sbd *sdp = GFS2_SB(inode);
208 struct buffer_head *bh;
209 struct gfs2_holder gh;
210 int error;
211 u32 new_flags, flags;
212
213 error = mnt_want_write(filp->f_path.mnt);
214 if (error)
215 return error;
216
217 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
218 if (error)
219 goto out_drop_write;
220
221 flags = ip->i_diskflags;
222 new_flags = (flags & ~mask) | (reqflags & mask);
223 if ((new_flags ^ flags) == 0)
224 goto out;
225
226 error = -EINVAL;
227 if ((new_flags ^ flags) & ~GFS2_FLAGS_USER_SET)
228 goto out;
229
230 error = -EPERM;
231 if (IS_IMMUTABLE(inode) && (new_flags & GFS2_DIF_IMMUTABLE))
232 goto out;
233 if (IS_APPEND(inode) && (new_flags & GFS2_DIF_APPENDONLY))
234 goto out;
235 if (((new_flags ^ flags) & GFS2_DIF_IMMUTABLE) &&
236 !capable(CAP_LINUX_IMMUTABLE))
237 goto out;
238 if (!IS_IMMUTABLE(inode)) {
239 error = gfs2_permission(inode, MAY_WRITE);
240 if (error)
241 goto out;
242 }
243 if ((flags ^ new_flags) & GFS2_DIF_JDATA) {
244 if (flags & GFS2_DIF_JDATA)
245 gfs2_log_flush(sdp, ip->i_gl);
246 error = filemap_fdatawrite(inode->i_mapping);
247 if (error)
248 goto out;
249 error = filemap_fdatawait(inode->i_mapping);
250 if (error)
251 goto out;
252 }
253 error = gfs2_trans_begin(sdp, RES_DINODE, 0);
254 if (error)
255 goto out;
256 error = gfs2_meta_inode_buffer(ip, &bh);
257 if (error)
258 goto out_trans_end;
259 gfs2_trans_add_bh(ip->i_gl, bh, 1);
260 ip->i_diskflags = new_flags;
261 gfs2_dinode_out(ip, bh->b_data);
262 brelse(bh);
263 gfs2_set_inode_flags(inode);
264 gfs2_set_aops(inode);
265 out_trans_end:
266 gfs2_trans_end(sdp);
267 out:
268 gfs2_glock_dq_uninit(&gh);
269 out_drop_write:
270 mnt_drop_write(filp->f_path.mnt);
271 return error;
272 }
273
274 static int gfs2_set_flags(struct file *filp, u32 __user *ptr)
275 {
276 struct inode *inode = filp->f_path.dentry->d_inode;
277 u32 fsflags, gfsflags;
278 if (get_user(fsflags, ptr))
279 return -EFAULT;
280 gfsflags = fsflags_cvt(fsflags_to_gfs2, fsflags);
281 if (!S_ISDIR(inode->i_mode)) {
282 if (gfsflags & GFS2_DIF_INHERIT_JDATA)
283 gfsflags ^= (GFS2_DIF_JDATA | GFS2_DIF_INHERIT_JDATA);
284 return do_gfs2_set_flags(filp, gfsflags, ~0);
285 }
286 return do_gfs2_set_flags(filp, gfsflags, ~GFS2_DIF_JDATA);
287 }
288
289 static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
290 {
291 switch(cmd) {
292 case FS_IOC_GETFLAGS:
293 return gfs2_get_flags(filp, (u32 __user *)arg);
294 case FS_IOC_SETFLAGS:
295 return gfs2_set_flags(filp, (u32 __user *)arg);
296 }
297 return -ENOTTY;
298 }
299
300 /**
301 * gfs2_allocate_page_backing - Use bmap to allocate blocks
302 * @page: The (locked) page to allocate backing for
303 *
304 * We try to allocate all the blocks required for the page in
305 * one go. This might fail for various reasons, so we keep
306 * trying until all the blocks to back this page are allocated.
307 * If some of the blocks are already allocated, thats ok too.
308 */
309
310 static int gfs2_allocate_page_backing(struct page *page)
311 {
312 struct inode *inode = page->mapping->host;
313 struct buffer_head bh;
314 unsigned long size = PAGE_CACHE_SIZE;
315 u64 lblock = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
316
317 do {
318 bh.b_state = 0;
319 bh.b_size = size;
320 gfs2_block_map(inode, lblock, &bh, 1);
321 if (!buffer_mapped(&bh))
322 return -EIO;
323 size -= bh.b_size;
324 lblock += (bh.b_size >> inode->i_blkbits);
325 } while(size > 0);
326 return 0;
327 }
328
329 /**
330 * gfs2_page_mkwrite - Make a shared, mmap()ed, page writable
331 * @vma: The virtual memory area
332 * @page: The page which is about to become writable
333 *
334 * When the page becomes writable, we need to ensure that we have
335 * blocks allocated on disk to back that page.
336 */
337
338 static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
339 {
340 struct page *page = vmf->page;
341 struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
342 struct gfs2_inode *ip = GFS2_I(inode);
343 struct gfs2_sbd *sdp = GFS2_SB(inode);
344 unsigned long last_index;
345 u64 pos = page->index << PAGE_CACHE_SHIFT;
346 unsigned int data_blocks, ind_blocks, rblocks;
347 int alloc_required = 0;
348 struct gfs2_holder gh;
349 struct gfs2_alloc *al;
350 int ret;
351
352 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
353 ret = gfs2_glock_nq(&gh);
354 if (ret)
355 goto out;
356
357 set_bit(GLF_DIRTY, &ip->i_gl->gl_flags);
358 set_bit(GIF_SW_PAGED, &ip->i_flags);
359
360 ret = gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE, &alloc_required);
361 if (ret || !alloc_required)
362 goto out_unlock;
363 ret = -ENOMEM;
364 al = gfs2_alloc_get(ip);
365 if (al == NULL)
366 goto out_unlock;
367
368 ret = gfs2_quota_lock_check(ip);
369 if (ret)
370 goto out_alloc_put;
371 gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks);
372 al->al_requested = data_blocks + ind_blocks;
373 ret = gfs2_inplace_reserve(ip);
374 if (ret)
375 goto out_quota_unlock;
376
377 rblocks = RES_DINODE + ind_blocks;
378 if (gfs2_is_jdata(ip))
379 rblocks += data_blocks ? data_blocks : 1;
380 if (ind_blocks || data_blocks)
381 rblocks += RES_STATFS + RES_QUOTA;
382 ret = gfs2_trans_begin(sdp, rblocks, 0);
383 if (ret)
384 goto out_trans_fail;
385
386 lock_page(page);
387 ret = -EINVAL;
388 last_index = ip->i_inode.i_size >> PAGE_CACHE_SHIFT;
389 if (page->index > last_index)
390 goto out_unlock_page;
391 ret = 0;
392 if (!PageUptodate(page) || page->mapping != ip->i_inode.i_mapping)
393 goto out_unlock_page;
394 if (gfs2_is_stuffed(ip)) {
395 ret = gfs2_unstuff_dinode(ip, page);
396 if (ret)
397 goto out_unlock_page;
398 }
399 ret = gfs2_allocate_page_backing(page);
400
401 out_unlock_page:
402 unlock_page(page);
403 gfs2_trans_end(sdp);
404 out_trans_fail:
405 gfs2_inplace_release(ip);
406 out_quota_unlock:
407 gfs2_quota_unlock(ip);
408 out_alloc_put:
409 gfs2_alloc_put(ip);
410 out_unlock:
411 gfs2_glock_dq(&gh);
412 out:
413 gfs2_holder_uninit(&gh);
414 if (ret == -ENOMEM)
415 ret = VM_FAULT_OOM;
416 else if (ret)
417 ret = VM_FAULT_SIGBUS;
418 return ret;
419 }
420
421 static const struct vm_operations_struct gfs2_vm_ops = {
422 .fault = filemap_fault,
423 .page_mkwrite = gfs2_page_mkwrite,
424 };
425
426 /**
427 * gfs2_mmap -
428 * @file: The file to map
429 * @vma: The VMA which described the mapping
430 *
431 * There is no need to get a lock here unless we should be updating
432 * atime. We ignore any locking errors since the only consequence is
433 * a missed atime update (which will just be deferred until later).
434 *
435 * Returns: 0
436 */
437
438 static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
439 {
440 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
441
442 if (!(file->f_flags & O_NOATIME)) {
443 struct gfs2_holder i_gh;
444 int error;
445
446 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
447 error = gfs2_glock_nq(&i_gh);
448 file_accessed(file);
449 if (error == 0)
450 gfs2_glock_dq_uninit(&i_gh);
451 }
452 vma->vm_ops = &gfs2_vm_ops;
453 vma->vm_flags |= VM_CAN_NONLINEAR;
454
455 return 0;
456 }
457
458 /**
459 * gfs2_open - open a file
460 * @inode: the inode to open
461 * @file: the struct file for this opening
462 *
463 * Returns: errno
464 */
465
466 static int gfs2_open(struct inode *inode, struct file *file)
467 {
468 struct gfs2_inode *ip = GFS2_I(inode);
469 struct gfs2_holder i_gh;
470 struct gfs2_file *fp;
471 int error;
472
473 fp = kzalloc(sizeof(struct gfs2_file), GFP_KERNEL);
474 if (!fp)
475 return -ENOMEM;
476
477 mutex_init(&fp->f_fl_mutex);
478
479 gfs2_assert_warn(GFS2_SB(inode), !file->private_data);
480 file->private_data = fp;
481
482 if (S_ISREG(ip->i_inode.i_mode)) {
483 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
484 &i_gh);
485 if (error)
486 goto fail;
487
488 if (!(file->f_flags & O_LARGEFILE) &&
489 ip->i_disksize > MAX_NON_LFS) {
490 error = -EOVERFLOW;
491 goto fail_gunlock;
492 }
493
494 gfs2_glock_dq_uninit(&i_gh);
495 }
496
497 return 0;
498
499 fail_gunlock:
500 gfs2_glock_dq_uninit(&i_gh);
501 fail:
502 file->private_data = NULL;
503 kfree(fp);
504 return error;
505 }
506
507 /**
508 * gfs2_close - called to close a struct file
509 * @inode: the inode the struct file belongs to
510 * @file: the struct file being closed
511 *
512 * Returns: errno
513 */
514
515 static int gfs2_close(struct inode *inode, struct file *file)
516 {
517 struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
518 struct gfs2_file *fp;
519
520 fp = file->private_data;
521 file->private_data = NULL;
522
523 if (gfs2_assert_warn(sdp, fp))
524 return -EIO;
525
526 kfree(fp);
527
528 return 0;
529 }
530
531 /**
532 * gfs2_fsync - sync the dirty data for a file (across the cluster)
533 * @file: the file that points to the dentry (we ignore this)
534 * @dentry: the dentry that points to the inode to sync
535 *
536 * The VFS will flush "normal" data for us. We only need to worry
537 * about metadata here. For journaled data, we just do a log flush
538 * as we can't avoid it. Otherwise we can just bale out if datasync
539 * is set. For stuffed inodes we must flush the log in order to
540 * ensure that all data is on disk.
541 *
542 * The call to write_inode_now() is there to write back metadata and
543 * the inode itself. It does also try and write the data, but thats
544 * (hopefully) a no-op due to the VFS having already called filemap_fdatawrite()
545 * for us.
546 *
547 * Returns: errno
548 */
549
550 static int gfs2_fsync(struct file *file, struct dentry *dentry, int datasync)
551 {
552 struct inode *inode = dentry->d_inode;
553 int sync_state = inode->i_state & (I_DIRTY_SYNC|I_DIRTY_DATASYNC);
554 int ret = 0;
555
556 if (gfs2_is_jdata(GFS2_I(inode))) {
557 gfs2_log_flush(GFS2_SB(inode), GFS2_I(inode)->i_gl);
558 return 0;
559 }
560
561 if (sync_state != 0) {
562 if (!datasync)
563 ret = write_inode_now(inode, 0);
564
565 if (gfs2_is_stuffed(GFS2_I(inode)))
566 gfs2_log_flush(GFS2_SB(inode), GFS2_I(inode)->i_gl);
567 }
568
569 return ret;
570 }
571
572 /**
573 * gfs2_file_aio_write - Perform a write to a file
574 * @iocb: The io context
575 * @iov: The data to write
576 * @nr_segs: Number of @iov segments
577 * @pos: The file position
578 *
579 * We have to do a lock/unlock here to refresh the inode size for
580 * O_APPEND writes, otherwise we can land up writing at the wrong
581 * offset. There is still a race, but provided the app is using its
582 * own file locking, this will make O_APPEND work as expected.
583 *
584 */
585
586 static ssize_t gfs2_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
587 unsigned long nr_segs, loff_t pos)
588 {
589 struct file *file = iocb->ki_filp;
590
591 if (file->f_flags & O_APPEND) {
592 struct dentry *dentry = file->f_dentry;
593 struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
594 struct gfs2_holder gh;
595 int ret;
596
597 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
598 if (ret)
599 return ret;
600 gfs2_glock_dq_uninit(&gh);
601 }
602
603 return generic_file_aio_write(iocb, iov, nr_segs, pos);
604 }
605
606 #ifdef CONFIG_GFS2_FS_LOCKING_DLM
607
608 /**
609 * gfs2_setlease - acquire/release a file lease
610 * @file: the file pointer
611 * @arg: lease type
612 * @fl: file lock
613 *
614 * We don't currently have a way to enforce a lease across the whole
615 * cluster; until we do, disable leases (by just returning -EINVAL),
616 * unless the administrator has requested purely local locking.
617 *
618 * Returns: errno
619 */
620
621 static int gfs2_setlease(struct file *file, long arg, struct file_lock **fl)
622 {
623 return -EINVAL;
624 }
625
626 /**
627 * gfs2_lock - acquire/release a posix lock on a file
628 * @file: the file pointer
629 * @cmd: either modify or retrieve lock state, possibly wait
630 * @fl: type and range of lock
631 *
632 * Returns: errno
633 */
634
635 static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
636 {
637 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
638 struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
639 struct lm_lockstruct *ls = &sdp->sd_lockstruct;
640
641 if (!(fl->fl_flags & FL_POSIX))
642 return -ENOLCK;
643 if (__mandatory_lock(&ip->i_inode))
644 return -ENOLCK;
645
646 if (cmd == F_CANCELLK) {
647 /* Hack: */
648 cmd = F_SETLK;
649 fl->fl_type = F_UNLCK;
650 }
651 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
652 return -EIO;
653 if (IS_GETLK(cmd))
654 return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl);
655 else if (fl->fl_type == F_UNLCK)
656 return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl);
657 else
658 return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl);
659 }
660
661 static int do_flock(struct file *file, int cmd, struct file_lock *fl)
662 {
663 struct gfs2_file *fp = file->private_data;
664 struct gfs2_holder *fl_gh = &fp->f_fl_gh;
665 struct gfs2_inode *ip = GFS2_I(file->f_path.dentry->d_inode);
666 struct gfs2_glock *gl;
667 unsigned int state;
668 int flags;
669 int error = 0;
670
671 state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
672 flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE;
673
674 mutex_lock(&fp->f_fl_mutex);
675
676 gl = fl_gh->gh_gl;
677 if (gl) {
678 if (fl_gh->gh_state == state)
679 goto out;
680 flock_lock_file_wait(file,
681 &(struct file_lock){.fl_type = F_UNLCK});
682 gfs2_glock_dq_wait(fl_gh);
683 gfs2_holder_reinit(state, flags, fl_gh);
684 } else {
685 error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr,
686 &gfs2_flock_glops, CREATE, &gl);
687 if (error)
688 goto out;
689 gfs2_holder_init(gl, state, flags, fl_gh);
690 gfs2_glock_put(gl);
691 }
692 error = gfs2_glock_nq(fl_gh);
693 if (error) {
694 gfs2_holder_uninit(fl_gh);
695 if (error == GLR_TRYFAILED)
696 error = -EAGAIN;
697 } else {
698 error = flock_lock_file_wait(file, fl);
699 gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error);
700 }
701
702 out:
703 mutex_unlock(&fp->f_fl_mutex);
704 return error;
705 }
706
707 static void do_unflock(struct file *file, struct file_lock *fl)
708 {
709 struct gfs2_file *fp = file->private_data;
710 struct gfs2_holder *fl_gh = &fp->f_fl_gh;
711
712 mutex_lock(&fp->f_fl_mutex);
713 flock_lock_file_wait(file, fl);
714 if (fl_gh->gh_gl)
715 gfs2_glock_dq_uninit(fl_gh);
716 mutex_unlock(&fp->f_fl_mutex);
717 }
718
719 /**
720 * gfs2_flock - acquire/release a flock lock on a file
721 * @file: the file pointer
722 * @cmd: either modify or retrieve lock state, possibly wait
723 * @fl: type and range of lock
724 *
725 * Returns: errno
726 */
727
728 static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl)
729 {
730 if (!(fl->fl_flags & FL_FLOCK))
731 return -ENOLCK;
732 if (fl->fl_type & LOCK_MAND)
733 return -EOPNOTSUPP;
734
735 if (fl->fl_type == F_UNLCK) {
736 do_unflock(file, fl);
737 return 0;
738 } else {
739 return do_flock(file, cmd, fl);
740 }
741 }
742
743 const struct file_operations gfs2_file_fops = {
744 .llseek = gfs2_llseek,
745 .read = do_sync_read,
746 .aio_read = generic_file_aio_read,
747 .write = do_sync_write,
748 .aio_write = gfs2_file_aio_write,
749 .unlocked_ioctl = gfs2_ioctl,
750 .mmap = gfs2_mmap,
751 .open = gfs2_open,
752 .release = gfs2_close,
753 .fsync = gfs2_fsync,
754 .lock = gfs2_lock,
755 .flock = gfs2_flock,
756 .splice_read = generic_file_splice_read,
757 .splice_write = generic_file_splice_write,
758 .setlease = gfs2_setlease,
759 };
760
761 const struct file_operations gfs2_dir_fops = {
762 .readdir = gfs2_readdir,
763 .unlocked_ioctl = gfs2_ioctl,
764 .open = gfs2_open,
765 .release = gfs2_close,
766 .fsync = gfs2_fsync,
767 .lock = gfs2_lock,
768 .flock = gfs2_flock,
769 };
770
771 #endif /* CONFIG_GFS2_FS_LOCKING_DLM */
772
773 const struct file_operations gfs2_file_fops_nolock = {
774 .llseek = gfs2_llseek,
775 .read = do_sync_read,
776 .aio_read = generic_file_aio_read,
777 .write = do_sync_write,
778 .aio_write = gfs2_file_aio_write,
779 .unlocked_ioctl = gfs2_ioctl,
780 .mmap = gfs2_mmap,
781 .open = gfs2_open,
782 .release = gfs2_close,
783 .fsync = gfs2_fsync,
784 .splice_read = generic_file_splice_read,
785 .splice_write = generic_file_splice_write,
786 .setlease = generic_setlease,
787 };
788
789 const struct file_operations gfs2_dir_fops_nolock = {
790 .readdir = gfs2_readdir,
791 .unlocked_ioctl = gfs2_ioctl,
792 .open = gfs2_open,
793 .release = gfs2_close,
794 .fsync = gfs2_fsync,
795 };
796
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