?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
update checkpatch.pl to version 0.15
[wrt350n-kernel.git] / fs / gfs2 / ops_file.c
blobf4842f2548cdb8c55346836aab9f287370e4e9f1
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/fs.h>
19 #include <linux/gfs2_ondisk.h>
20 #include <linux/ext2_fs.h>
21 #include <linux/crc32.h>
22 #include <linux/lm_interface.h>
23 #include <linux/writeback.h>
24 #include <asm/uaccess.h>
25
26 #include "gfs2.h"
27 #include "incore.h"
28 #include "bmap.h"
29 #include "dir.h"
30 #include "glock.h"
31 #include "glops.h"
32 #include "inode.h"
33 #include "lm.h"
34 #include "log.h"
35 #include "meta_io.h"
36 #include "quota.h"
37 #include "rgrp.h"
38 #include "trans.h"
39 #include "util.h"
40 #include "eaops.h"
41 #include "ops_address.h"
42
43 /**
44 * gfs2_llseek - seek to a location in a file
45 * @file: the file
46 * @offset: the offset
47 * @origin: 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 origin)
56 {
57 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
58 struct gfs2_holder i_gh;
59 loff_t error;
60
61 if (origin == 2) {
62 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
63 &i_gh);
64 if (!error) {
65 error = remote_llseek(file, offset, origin);
66 gfs2_glock_dq_uninit(&i_gh);
67 }
68 } else
69 error = remote_llseek(file, offset, origin);
70
71 return error;
72 }
73
74 /**
75 * gfs2_readdir - Read directory entries from a directory
76 * @file: The directory to read from
77 * @dirent: Buffer for dirents
78 * @filldir: Function used to do the copying
79 *
80 * Returns: errno
81 */
82
83 static int gfs2_readdir(struct file *file, void *dirent, filldir_t filldir)
84 {
85 struct inode *dir = file->f_mapping->host;
86 struct gfs2_inode *dip = GFS2_I(dir);
87 struct gfs2_holder d_gh;
88 u64 offset = file->f_pos;
89 int error;
90
91 gfs2_holder_init(dip->i_gl, LM_ST_SHARED, GL_ATIME, &d_gh);
92 error = gfs2_glock_nq_atime(&d_gh);
93 if (error) {
94 gfs2_holder_uninit(&d_gh);
95 return error;
96 }
97
98 error = gfs2_dir_read(dir, &offset, dirent, filldir);
99
100 gfs2_glock_dq_uninit(&d_gh);
101
102 file->f_pos = offset;
103
104 return error;
105 }
106
107 /**
108 * fsflags_cvt
109 * @table: A table of 32 u32 flags
110 * @val: a 32 bit value to convert
111 *
112 * This function can be used to convert between fsflags values and
113 * GFS2's own flags values.
114 *
115 * Returns: the converted flags
116 */
117 static u32 fsflags_cvt(const u32 *table, u32 val)
118 {
119 u32 res = 0;
120 while(val) {
121 if (val & 1)
122 res |= *table;
123 table++;
124 val >>= 1;
125 }
126 return res;
127 }
128
129 static const u32 fsflags_to_gfs2[32] = {
130 [3] = GFS2_DIF_SYNC,
131 [4] = GFS2_DIF_IMMUTABLE,
132 [5] = GFS2_DIF_APPENDONLY,
133 [7] = GFS2_DIF_NOATIME,
134 [12] = GFS2_DIF_EXHASH,
135 [14] = GFS2_DIF_INHERIT_JDATA,
136 [20] = GFS2_DIF_INHERIT_DIRECTIO,
137 };
138
139 static const u32 gfs2_to_fsflags[32] = {
140 [gfs2fl_Sync] = FS_SYNC_FL,
141 [gfs2fl_Immutable] = FS_IMMUTABLE_FL,
142 [gfs2fl_AppendOnly] = FS_APPEND_FL,
143 [gfs2fl_NoAtime] = FS_NOATIME_FL,
144 [gfs2fl_ExHash] = FS_INDEX_FL,
145 [gfs2fl_InheritDirectio] = FS_DIRECTIO_FL,
146 [gfs2fl_InheritJdata] = FS_JOURNAL_DATA_FL,
147 };
148
149 static int gfs2_get_flags(struct file *filp, u32 __user *ptr)
150 {
151 struct inode *inode = filp->f_path.dentry->d_inode;
152 struct gfs2_inode *ip = GFS2_I(inode);
153 struct gfs2_holder gh;
154 int error;
155 u32 fsflags;
156
157 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh);
158 error = gfs2_glock_nq_atime(&gh);
159 if (error)
160 return error;
161
162 fsflags = fsflags_cvt(gfs2_to_fsflags, ip->i_di.di_flags);
163 if (!S_ISDIR(inode->i_mode)) {
164 if (ip->i_di.di_flags & GFS2_DIF_JDATA)
165 fsflags |= FS_JOURNAL_DATA_FL;
166 if (ip->i_di.di_flags & GFS2_DIF_DIRECTIO)
167 fsflags |= FS_DIRECTIO_FL;
168 }
169 if (put_user(fsflags, ptr))
170 error = -EFAULT;
171
172 gfs2_glock_dq(&gh);
173 gfs2_holder_uninit(&gh);
174 return error;
175 }
176
177 void gfs2_set_inode_flags(struct inode *inode)
178 {
179 struct gfs2_inode *ip = GFS2_I(inode);
180 struct gfs2_dinode_host *di = &ip->i_di;
181 unsigned int flags = inode->i_flags;
182
183 flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
184 if (di->di_flags & GFS2_DIF_IMMUTABLE)
185 flags |= S_IMMUTABLE;
186 if (di->di_flags & GFS2_DIF_APPENDONLY)
187 flags |= S_APPEND;
188 if (di->di_flags & GFS2_DIF_NOATIME)
189 flags |= S_NOATIME;
190 if (di->di_flags & GFS2_DIF_SYNC)
191 flags |= S_SYNC;
192 inode->i_flags = flags;
193 }
194
195 /* Flags that can be set by user space */
196 #define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA| \
197 GFS2_DIF_DIRECTIO| \
198 GFS2_DIF_IMMUTABLE| \
199 GFS2_DIF_APPENDONLY| \
200 GFS2_DIF_NOATIME| \
201 GFS2_DIF_SYNC| \
202 GFS2_DIF_SYSTEM| \
203 GFS2_DIF_INHERIT_DIRECTIO| \
204 GFS2_DIF_INHERIT_JDATA)
205
206 /**
207 * gfs2_set_flags - set flags on an inode
208 * @inode: The inode
209 * @flags: The flags to set
210 * @mask: Indicates which flags are valid
211 *
212 */
213 static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask)
214 {
215 struct inode *inode = filp->f_path.dentry->d_inode;
216 struct gfs2_inode *ip = GFS2_I(inode);
217 struct gfs2_sbd *sdp = GFS2_SB(inode);
218 struct buffer_head *bh;
219 struct gfs2_holder gh;
220 int error;
221 u32 new_flags, flags;
222
223 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
224 if (error)
225 return error;
226
227 flags = ip->i_di.di_flags;
228 new_flags = (flags & ~mask) | (reqflags & mask);
229 if ((new_flags ^ flags) == 0)
230 goto out;
231
232 error = -EINVAL;
233 if ((new_flags ^ flags) & ~GFS2_FLAGS_USER_SET)
234 goto out;
235
236 error = -EPERM;
237 if (IS_IMMUTABLE(inode) && (new_flags & GFS2_DIF_IMMUTABLE))
238 goto out;
239 if (IS_APPEND(inode) && (new_flags & GFS2_DIF_APPENDONLY))
240 goto out;
241 if (((new_flags ^ flags) & GFS2_DIF_IMMUTABLE) &&
242 !capable(CAP_LINUX_IMMUTABLE))
243 goto out;
244 if (!IS_IMMUTABLE(inode)) {
245 error = permission(inode, MAY_WRITE, NULL);
246 if (error)
247 goto out;
248 }
249 if ((flags ^ new_flags) & GFS2_DIF_JDATA) {
250 if (flags & GFS2_DIF_JDATA)
251 gfs2_log_flush(sdp, ip->i_gl);
252 error = filemap_fdatawrite(inode->i_mapping);
253 if (error)
254 goto out;
255 error = filemap_fdatawait(inode->i_mapping);
256 if (error)
257 goto out;
258 }
259 error = gfs2_trans_begin(sdp, RES_DINODE, 0);
260 if (error)
261 goto out;
262 error = gfs2_meta_inode_buffer(ip, &bh);
263 if (error)
264 goto out_trans_end;
265 gfs2_trans_add_bh(ip->i_gl, bh, 1);
266 ip->i_di.di_flags = new_flags;
267 gfs2_dinode_out(ip, bh->b_data);
268 brelse(bh);
269 gfs2_set_inode_flags(inode);
270 gfs2_set_aops(inode);
271 out_trans_end:
272 gfs2_trans_end(sdp);
273 out:
274 gfs2_glock_dq_uninit(&gh);
275 return error;
276 }
277
278 static int gfs2_set_flags(struct file *filp, u32 __user *ptr)
279 {
280 struct inode *inode = filp->f_path.dentry->d_inode;
281 u32 fsflags, gfsflags;
282 if (get_user(fsflags, ptr))
283 return -EFAULT;
284 gfsflags = fsflags_cvt(fsflags_to_gfs2, fsflags);
285 if (!S_ISDIR(inode->i_mode)) {
286 if (gfsflags & GFS2_DIF_INHERIT_JDATA)
287 gfsflags ^= (GFS2_DIF_JDATA | GFS2_DIF_INHERIT_JDATA);
288 if (gfsflags & GFS2_DIF_INHERIT_DIRECTIO)
289 gfsflags ^= (GFS2_DIF_DIRECTIO | GFS2_DIF_INHERIT_DIRECTIO);
290 return do_gfs2_set_flags(filp, gfsflags, ~0);
291 }
292 return do_gfs2_set_flags(filp, gfsflags, ~GFS2_DIF_JDATA);
293 }
294
295 static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
296 {
297 switch(cmd) {
298 case FS_IOC_GETFLAGS:
299 return gfs2_get_flags(filp, (u32 __user *)arg);
300 case FS_IOC_SETFLAGS:
301 return gfs2_set_flags(filp, (u32 __user *)arg);
302 }
303 return -ENOTTY;
304 }
305
306 /**
307 * gfs2_allocate_page_backing - Use bmap to allocate blocks
308 * @page: The (locked) page to allocate backing for
309 *
310 * We try to allocate all the blocks required for the page in
311 * one go. This might fail for various reasons, so we keep
312 * trying until all the blocks to back this page are allocated.
313 * If some of the blocks are already allocated, thats ok too.
314 */
315
316 static int gfs2_allocate_page_backing(struct page *page)
317 {
318 struct inode *inode = page->mapping->host;
319 struct buffer_head bh;
320 unsigned long size = PAGE_CACHE_SIZE;
321 u64 lblock = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
322
323 do {
324 bh.b_state = 0;
325 bh.b_size = size;
326 gfs2_block_map(inode, lblock, &bh, 1);
327 if (!buffer_mapped(&bh))
328 return -EIO;
329 size -= bh.b_size;
330 lblock += (bh.b_size >> inode->i_blkbits);
331 } while(size > 0);
332 return 0;
333 }
334
335 /**
336 * gfs2_page_mkwrite - Make a shared, mmap()ed, page writable
337 * @vma: The virtual memory area
338 * @page: The page which is about to become writable
339 *
340 * When the page becomes writable, we need to ensure that we have
341 * blocks allocated on disk to back that page.
342 */
343
344 static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct page *page)
345 {
346 struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
347 struct gfs2_inode *ip = GFS2_I(inode);
348 struct gfs2_sbd *sdp = GFS2_SB(inode);
349 unsigned long last_index;
350 u64 pos = page->index << (PAGE_CACHE_SIZE - inode->i_blkbits);
351 unsigned int data_blocks, ind_blocks, rblocks;
352 int alloc_required = 0;
353 struct gfs2_holder gh;
354 struct gfs2_alloc *al;
355 int ret;
356
357 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ATIME, &gh);
358 ret = gfs2_glock_nq_atime(&gh);
359 if (ret)
360 goto out;
361
362 set_bit(GIF_SW_PAGED, &ip->i_flags);
363 gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks);
364 ret = gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE, &alloc_required);
365 if (ret || !alloc_required)
366 goto out_unlock;
367 ret = -ENOMEM;
368 al = gfs2_alloc_get(ip);
369 if (al == NULL)
370 goto out_unlock;
371
372 ret = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
373 if (ret)
374 goto out_alloc_put;
375 ret = gfs2_quota_check(ip, ip->i_inode.i_uid, ip->i_inode.i_gid);
376 if (ret)
377 goto out_quota_unlock;
378 al->al_requested = data_blocks + ind_blocks;
379 ret = gfs2_inplace_reserve(ip);
380 if (ret)
381 goto out_quota_unlock;
382
383 rblocks = RES_DINODE + ind_blocks;
384 if (gfs2_is_jdata(ip))
385 rblocks += data_blocks ? data_blocks : 1;
386 if (ind_blocks || data_blocks)
387 rblocks += RES_STATFS + RES_QUOTA;
388 ret = gfs2_trans_begin(sdp, rblocks, 0);
389 if (ret)
390 goto out_trans_fail;
391
392 lock_page(page);
393 ret = -EINVAL;
394 last_index = ip->i_inode.i_size >> PAGE_CACHE_SHIFT;
395 if (page->index > last_index)
396 goto out_unlock_page;
397 ret = 0;
398 if (!PageUptodate(page) || page->mapping != ip->i_inode.i_mapping)
399 goto out_unlock_page;
400 if (gfs2_is_stuffed(ip)) {
401 ret = gfs2_unstuff_dinode(ip, page);
402 if (ret)
403 goto out_unlock_page;
404 }
405 ret = gfs2_allocate_page_backing(page);
406
407 out_unlock_page:
408 unlock_page(page);
409 gfs2_trans_end(sdp);
410 out_trans_fail:
411 gfs2_inplace_release(ip);
412 out_quota_unlock:
413 gfs2_quota_unlock(ip);
414 out_alloc_put:
415 gfs2_alloc_put(ip);
416 out_unlock:
417 gfs2_glock_dq(&gh);
418 out:
419 gfs2_holder_uninit(&gh);
420 return ret;
421 }
422
423 static struct vm_operations_struct gfs2_vm_ops = {
424 .fault = filemap_fault,
425 .page_mkwrite = gfs2_page_mkwrite,
426 };
427
428
429 /**
430 * gfs2_mmap -
431 * @file: The file to map
432 * @vma: The VMA which described the mapping
433 *
434 * Returns: 0 or error code
435 */
436
437 static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
438 {
439 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
440 struct gfs2_holder i_gh;
441 int error;
442
443 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &i_gh);
444 error = gfs2_glock_nq_atime(&i_gh);
445 if (error) {
446 gfs2_holder_uninit(&i_gh);
447 return error;
448 }
449
450 vma->vm_ops = &gfs2_vm_ops;
451
452 gfs2_glock_dq_uninit(&i_gh);
453
454 return error;
455 }
456
457 /**
458 * gfs2_open - open a file
459 * @inode: the inode to open
460 * @file: the struct file for this opening
461 *
462 * Returns: errno
463 */
464
465 static int gfs2_open(struct inode *inode, struct file *file)
466 {
467 struct gfs2_inode *ip = GFS2_I(inode);
468 struct gfs2_holder i_gh;
469 struct gfs2_file *fp;
470 int error;
471
472 fp = kzalloc(sizeof(struct gfs2_file), GFP_KERNEL);
473 if (!fp)
474 return -ENOMEM;
475
476 mutex_init(&fp->f_fl_mutex);
477
478 gfs2_assert_warn(GFS2_SB(inode), !file->private_data);
479 file->private_data = fp;
480
481 if (S_ISREG(ip->i_inode.i_mode)) {
482 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
483 &i_gh);
484 if (error)
485 goto fail;
486
487 if (!(file->f_flags & O_LARGEFILE) &&
488 ip->i_di.di_size > MAX_NON_LFS) {
489 error = -EOVERFLOW;
490 goto fail_gunlock;
491 }
492
493 /* Listen to the Direct I/O flag */
494
495 if (ip->i_di.di_flags & GFS2_DIF_DIRECTIO)
496 file->f_flags |= O_DIRECT;
497
498 gfs2_glock_dq_uninit(&i_gh);
499 }
500
501 return 0;
502
503 fail_gunlock:
504 gfs2_glock_dq_uninit(&i_gh);
505 fail:
506 file->private_data = NULL;
507 kfree(fp);
508 return error;
509 }
510
511 /**
512 * gfs2_close - called to close a struct file
513 * @inode: the inode the struct file belongs to
514 * @file: the struct file being closed
515 *
516 * Returns: errno
517 */
518
519 static int gfs2_close(struct inode *inode, struct file *file)
520 {
521 struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
522 struct gfs2_file *fp;
523
524 fp = file->private_data;
525 file->private_data = NULL;
526
527 if (gfs2_assert_warn(sdp, fp))
528 return -EIO;
529
530 kfree(fp);
531
532 return 0;
533 }
534
535 /**
536 * gfs2_fsync - sync the dirty data for a file (across the cluster)
537 * @file: the file that points to the dentry (we ignore this)
538 * @dentry: the dentry that points to the inode to sync
539 *
540 * The VFS will flush "normal" data for us. We only need to worry
541 * about metadata here. For journaled data, we just do a log flush
542 * as we can't avoid it. Otherwise we can just bale out if datasync
543 * is set. For stuffed inodes we must flush the log in order to
544 * ensure that all data is on disk.
545 *
546 * The call to write_inode_now() is there to write back metadata and
547 * the inode itself. It does also try and write the data, but thats
548 * (hopefully) a no-op due to the VFS having already called filemap_fdatawrite()
549 * for us.
550 *
551 * Returns: errno
552 */
553
554 static int gfs2_fsync(struct file *file, struct dentry *dentry, int datasync)
555 {
556 struct inode *inode = dentry->d_inode;
557 int sync_state = inode->i_state & (I_DIRTY_SYNC|I_DIRTY_DATASYNC);
558 int ret = 0;
559
560 if (gfs2_is_jdata(GFS2_I(inode))) {
561 gfs2_log_flush(GFS2_SB(inode), GFS2_I(inode)->i_gl);
562 return 0;
563 }
564
565 if (sync_state != 0) {
566 if (!datasync)
567 ret = write_inode_now(inode, 0);
568
569 if (gfs2_is_stuffed(GFS2_I(inode)))
570 gfs2_log_flush(GFS2_SB(inode), GFS2_I(inode)->i_gl);
571 }
572
573 return ret;
574 }
575
576 /**
577 * gfs2_setlease - acquire/release a file lease
578 * @file: the file pointer
579 * @arg: lease type
580 * @fl: file lock
581 *
582 * Returns: errno
583 */
584
585 static int gfs2_setlease(struct file *file, long arg, struct file_lock **fl)
586 {
587 struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
588
589 /*
590 * We don't currently have a way to enforce a lease across the whole
591 * cluster; until we do, disable leases (by just returning -EINVAL),
592 * unless the administrator has requested purely local locking.
593 */
594 if (!sdp->sd_args.ar_localflocks)
595 return -EINVAL;
596 return generic_setlease(file, arg, fl);
597 }
598
599 /**
600 * gfs2_lock - acquire/release a posix lock on a file
601 * @file: the file pointer
602 * @cmd: either modify or retrieve lock state, possibly wait
603 * @fl: type and range of lock
604 *
605 * Returns: errno
606 */
607
608 static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
609 {
610 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
611 struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
612 struct lm_lockname name =
613 { .ln_number = ip->i_no_addr,
614 .ln_type = LM_TYPE_PLOCK };
615
616 if (!(fl->fl_flags & FL_POSIX))
617 return -ENOLCK;
618 if (__mandatory_lock(&ip->i_inode))
619 return -ENOLCK;
620
621 if (cmd == F_CANCELLK) {
622 /* Hack: */
623 cmd = F_SETLK;
624 fl->fl_type = F_UNLCK;
625 }
626 if (IS_GETLK(cmd))
627 return gfs2_lm_plock_get(sdp, &name, file, fl);
628 else if (fl->fl_type == F_UNLCK)
629 return gfs2_lm_punlock(sdp, &name, file, fl);
630 else
631 return gfs2_lm_plock(sdp, &name, file, cmd, fl);
632 }
633
634 static int do_flock(struct file *file, int cmd, struct file_lock *fl)
635 {
636 struct gfs2_file *fp = file->private_data;
637 struct gfs2_holder *fl_gh = &fp->f_fl_gh;
638 struct gfs2_inode *ip = GFS2_I(file->f_path.dentry->d_inode);
639 struct gfs2_glock *gl;
640 unsigned int state;
641 int flags;
642 int error = 0;
643
644 state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
645 flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE
646 | GL_FLOCK;
647
648 mutex_lock(&fp->f_fl_mutex);
649
650 gl = fl_gh->gh_gl;
651 if (gl) {
652 if (fl_gh->gh_state == state)
653 goto out;
654 flock_lock_file_wait(file,
655 &(struct file_lock){.fl_type = F_UNLCK});
656 gfs2_glock_dq_wait(fl_gh);
657 gfs2_holder_reinit(state, flags, fl_gh);
658 } else {
659 error = gfs2_glock_get(GFS2_SB(&ip->i_inode),
660 ip->i_no_addr, &gfs2_flock_glops,
661 CREATE, &gl);
662 if (error)
663 goto out;
664 gfs2_holder_init(gl, state, flags, fl_gh);
665 gfs2_glock_put(gl);
666 }
667 error = gfs2_glock_nq(fl_gh);
668 if (error) {
669 gfs2_holder_uninit(fl_gh);
670 if (error == GLR_TRYFAILED)
671 error = -EAGAIN;
672 } else {
673 error = flock_lock_file_wait(file, fl);
674 gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error);
675 }
676
677 out:
678 mutex_unlock(&fp->f_fl_mutex);
679 return error;
680 }
681
682 static void do_unflock(struct file *file, struct file_lock *fl)
683 {
684 struct gfs2_file *fp = file->private_data;
685 struct gfs2_holder *fl_gh = &fp->f_fl_gh;
686
687 mutex_lock(&fp->f_fl_mutex);
688 flock_lock_file_wait(file, fl);
689 if (fl_gh->gh_gl)
690 gfs2_glock_dq_uninit(fl_gh);
691 mutex_unlock(&fp->f_fl_mutex);
692 }
693
694 /**
695 * gfs2_flock - acquire/release a flock lock on a file
696 * @file: the file pointer
697 * @cmd: either modify or retrieve lock state, possibly wait
698 * @fl: type and range of lock
699 *
700 * Returns: errno
701 */
702
703 static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl)
704 {
705 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
706
707 if (!(fl->fl_flags & FL_FLOCK))
708 return -ENOLCK;
709 if (__mandatory_lock(&ip->i_inode))
710 return -ENOLCK;
711
712 if (fl->fl_type == F_UNLCK) {
713 do_unflock(file, fl);
714 return 0;
715 } else {
716 return do_flock(file, cmd, fl);
717 }
718 }
719
720 const struct file_operations gfs2_file_fops = {
721 .llseek = gfs2_llseek,
722 .read = do_sync_read,
723 .aio_read = generic_file_aio_read,
724 .write = do_sync_write,
725 .aio_write = generic_file_aio_write,
726 .unlocked_ioctl = gfs2_ioctl,
727 .mmap = gfs2_mmap,
728 .open = gfs2_open,
729 .release = gfs2_close,
730 .fsync = gfs2_fsync,
731 .lock = gfs2_lock,
732 .flock = gfs2_flock,
733 .splice_read = generic_file_splice_read,
734 .splice_write = generic_file_splice_write,
735 .setlease = gfs2_setlease,
736 };
737
738 const struct file_operations gfs2_dir_fops = {
739 .readdir = gfs2_readdir,
740 .unlocked_ioctl = gfs2_ioctl,
741 .open = gfs2_open,
742 .release = gfs2_close,
743 .fsync = gfs2_fsync,
744 .lock = gfs2_lock,
745 .flock = gfs2_flock,
746 };
747
748 const struct file_operations gfs2_file_fops_nolock = {
749 .llseek = gfs2_llseek,
750 .read = do_sync_read,
751 .aio_read = generic_file_aio_read,
752 .write = do_sync_write,
753 .aio_write = generic_file_aio_write,
754 .unlocked_ioctl = gfs2_ioctl,
755 .mmap = gfs2_mmap,
756 .open = gfs2_open,
757 .release = gfs2_close,
758 .fsync = gfs2_fsync,
759 .splice_read = generic_file_splice_read,
760 .splice_write = generic_file_splice_write,
761 .setlease = gfs2_setlease,
762 };
763
764 const struct file_operations gfs2_dir_fops_nolock = {
765 .readdir = gfs2_readdir,
766 .unlocked_ioctl = gfs2_ioctl,
767 .open = gfs2_open,
768 .release = gfs2_close,
769 .fsync = gfs2_fsync,
770 };
771
WRT350N Kernel Patches