?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Ath5k: lock beacons
[linux-2.6/mini2440.git] / fs / gfs2 / ops_file.c
blobe9a366d4411cf2412e82d9e645609c69c0dfcd7d
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/lm_interface.h>
24 #include <linux/writeback.h>
25 #include <asm/uaccess.h>
26
27 #include "gfs2.h"
28 #include "incore.h"
29 #include "bmap.h"
30 #include "dir.h"
31 #include "glock.h"
32 #include "glops.h"
33 #include "inode.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 #include "ops_inode.h"
43
44 /**
45 * gfs2_llseek - seek to a location in a file
46 * @file: the file
47 * @offset: the offset
48 * @origin: Where to seek from (SEEK_SET, SEEK_CUR, or SEEK_END)
49 *
50 * SEEK_END requires the glock for the file because it references the
51 * file's size.
52 *
53 * Returns: The new offset, or errno
54 */
55
56 static loff_t gfs2_llseek(struct file *file, loff_t offset, int origin)
57 {
58 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
59 struct gfs2_holder i_gh;
60 loff_t error;
61
62 if (origin == 2) {
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_unlocked(file, offset, origin);
67 gfs2_glock_dq_uninit(&i_gh);
68 }
69 } else
70 error = generic_file_llseek_unlocked(file, offset, origin);
71
72 return error;
73 }
74
75 /**
76 * gfs2_readdir - Read directory entries from a directory
77 * @file: The directory to read from
78 * @dirent: Buffer for dirents
79 * @filldir: Function used to do the copying
80 *
81 * Returns: errno
82 */
83
84 static int gfs2_readdir(struct file *file, void *dirent, filldir_t filldir)
85 {
86 struct inode *dir = file->f_mapping->host;
87 struct gfs2_inode *dip = GFS2_I(dir);
88 struct gfs2_holder d_gh;
89 u64 offset = file->f_pos;
90 int error;
91
92 gfs2_holder_init(dip->i_gl, LM_ST_SHARED, GL_ATIME, &d_gh);
93 error = gfs2_glock_nq_atime(&d_gh);
94 if (error) {
95 gfs2_holder_uninit(&d_gh);
96 return error;
97 }
98
99 error = gfs2_dir_read(dir, &offset, dirent, filldir);
100
101 gfs2_glock_dq_uninit(&d_gh);
102
103 file->f_pos = offset;
104
105 return error;
106 }
107
108 /**
109 * fsflags_cvt
110 * @table: A table of 32 u32 flags
111 * @val: a 32 bit value to convert
112 *
113 * This function can be used to convert between fsflags values and
114 * GFS2's own flags values.
115 *
116 * Returns: the converted flags
117 */
118 static u32 fsflags_cvt(const u32 *table, u32 val)
119 {
120 u32 res = 0;
121 while(val) {
122 if (val & 1)
123 res |= *table;
124 table++;
125 val >>= 1;
126 }
127 return res;
128 }
129
130 static const u32 fsflags_to_gfs2[32] = {
131 [3] = GFS2_DIF_SYNC,
132 [4] = GFS2_DIF_IMMUTABLE,
133 [5] = GFS2_DIF_APPENDONLY,
134 [7] = GFS2_DIF_NOATIME,
135 [12] = GFS2_DIF_EXHASH,
136 [14] = GFS2_DIF_INHERIT_JDATA,
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_InheritJdata] = FS_JOURNAL_DATA_FL,
146 };
147
148 static int gfs2_get_flags(struct file *filp, u32 __user *ptr)
149 {
150 struct inode *inode = filp->f_path.dentry->d_inode;
151 struct gfs2_inode *ip = GFS2_I(inode);
152 struct gfs2_holder gh;
153 int error;
154 u32 fsflags;
155
156 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh);
157 error = gfs2_glock_nq_atime(&gh);
158 if (error)
159 return error;
160
161 fsflags = fsflags_cvt(gfs2_to_fsflags, ip->i_di.di_flags);
162 if (!S_ISDIR(inode->i_mode) && ip->i_di.di_flags & GFS2_DIF_JDATA)
163 fsflags |= FS_JOURNAL_DATA_FL;
164 if (put_user(fsflags, ptr))
165 error = -EFAULT;
166
167 gfs2_glock_dq(&gh);
168 gfs2_holder_uninit(&gh);
169 return error;
170 }
171
172 void gfs2_set_inode_flags(struct inode *inode)
173 {
174 struct gfs2_inode *ip = GFS2_I(inode);
175 struct gfs2_dinode_host *di = &ip->i_di;
176 unsigned int flags = inode->i_flags;
177
178 flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
179 if (di->di_flags & GFS2_DIF_IMMUTABLE)
180 flags |= S_IMMUTABLE;
181 if (di->di_flags & GFS2_DIF_APPENDONLY)
182 flags |= S_APPEND;
183 if (di->di_flags & GFS2_DIF_NOATIME)
184 flags |= S_NOATIME;
185 if (di->di_flags & GFS2_DIF_SYNC)
186 flags |= S_SYNC;
187 inode->i_flags = flags;
188 }
189
190 /* Flags that can be set by user space */
191 #define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA| \
192 GFS2_DIF_IMMUTABLE| \
193 GFS2_DIF_APPENDONLY| \
194 GFS2_DIF_NOATIME| \
195 GFS2_DIF_SYNC| \
196 GFS2_DIF_SYSTEM| \
197 GFS2_DIF_INHERIT_JDATA)
198
199 /**
200 * gfs2_set_flags - set flags on an inode
201 * @inode: The inode
202 * @flags: The flags to set
203 * @mask: Indicates which flags are valid
204 *
205 */
206 static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask)
207 {
208 struct inode *inode = filp->f_path.dentry->d_inode;
209 struct gfs2_inode *ip = GFS2_I(inode);
210 struct gfs2_sbd *sdp = GFS2_SB(inode);
211 struct buffer_head *bh;
212 struct gfs2_holder gh;
213 int error;
214 u32 new_flags, flags;
215
216 error = mnt_want_write(filp->f_path.mnt);
217 if (error)
218 return error;
219
220 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
221 if (error)
222 goto out_drop_write;
223
224 flags = ip->i_di.di_flags;
225 new_flags = (flags & ~mask) | (reqflags & mask);
226 if ((new_flags ^ flags) == 0)
227 goto out;
228
229 error = -EINVAL;
230 if ((new_flags ^ flags) & ~GFS2_FLAGS_USER_SET)
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 (flags & GFS2_DIF_JDATA)
248 gfs2_log_flush(sdp, ip->i_gl);
249 error = filemap_fdatawrite(inode->i_mapping);
250 if (error)
251 goto out;
252 error = filemap_fdatawait(inode->i_mapping);
253 if (error)
254 goto out;
255 }
256 error = gfs2_trans_begin(sdp, RES_DINODE, 0);
257 if (error)
258 goto out;
259 error = gfs2_meta_inode_buffer(ip, &bh);
260 if (error)
261 goto out_trans_end;
262 gfs2_trans_add_bh(ip->i_gl, bh, 1);
263 ip->i_di.di_flags = new_flags;
264 gfs2_dinode_out(ip, bh->b_data);
265 brelse(bh);
266 gfs2_set_inode_flags(inode);
267 gfs2_set_aops(inode);
268 out_trans_end:
269 gfs2_trans_end(sdp);
270 out:
271 gfs2_glock_dq_uninit(&gh);
272 out_drop_write:
273 mnt_drop_write(filp->f_path.mnt);
274 return error;
275 }
276
277 static int gfs2_set_flags(struct file *filp, u32 __user *ptr)
278 {
279 struct inode *inode = filp->f_path.dentry->d_inode;
280 u32 fsflags, gfsflags;
281 if (get_user(fsflags, ptr))
282 return -EFAULT;
283 gfsflags = fsflags_cvt(fsflags_to_gfs2, fsflags);
284 if (!S_ISDIR(inode->i_mode)) {
285 if (gfsflags & GFS2_DIF_INHERIT_JDATA)
286 gfsflags ^= (GFS2_DIF_JDATA | GFS2_DIF_INHERIT_JDATA);
287 return do_gfs2_set_flags(filp, gfsflags, ~0);
288 }
289 return do_gfs2_set_flags(filp, gfsflags, ~GFS2_DIF_JDATA);
290 }
291
292 static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
293 {
294 switch(cmd) {
295 case FS_IOC_GETFLAGS:
296 return gfs2_get_flags(filp, (u32 __user *)arg);
297 case FS_IOC_SETFLAGS:
298 return gfs2_set_flags(filp, (u32 __user *)arg);
299 }
300 return -ENOTTY;
301 }
302
303 /**
304 * gfs2_allocate_page_backing - Use bmap to allocate blocks
305 * @page: The (locked) page to allocate backing for
306 *
307 * We try to allocate all the blocks required for the page in
308 * one go. This might fail for various reasons, so we keep
309 * trying until all the blocks to back this page are allocated.
310 * If some of the blocks are already allocated, thats ok too.
311 */
312
313 static int gfs2_allocate_page_backing(struct page *page)
314 {
315 struct inode *inode = page->mapping->host;
316 struct buffer_head bh;
317 unsigned long size = PAGE_CACHE_SIZE;
318 u64 lblock = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
319
320 do {
321 bh.b_state = 0;
322 bh.b_size = size;
323 gfs2_block_map(inode, lblock, &bh, 1);
324 if (!buffer_mapped(&bh))
325 return -EIO;
326 size -= bh.b_size;
327 lblock += (bh.b_size >> inode->i_blkbits);
328 } while(size > 0);
329 return 0;
330 }
331
332 /**
333 * gfs2_page_mkwrite - Make a shared, mmap()ed, page writable
334 * @vma: The virtual memory area
335 * @page: The page which is about to become writable
336 *
337 * When the page becomes writable, we need to ensure that we have
338 * blocks allocated on disk to back that page.
339 */
340
341 static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct page *page)
342 {
343 struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
344 struct gfs2_inode *ip = GFS2_I(inode);
345 struct gfs2_sbd *sdp = GFS2_SB(inode);
346 unsigned long last_index;
347 u64 pos = page->index << (PAGE_CACHE_SIZE - inode->i_blkbits);
348 unsigned int data_blocks, ind_blocks, rblocks;
349 int alloc_required = 0;
350 struct gfs2_holder gh;
351 struct gfs2_alloc *al;
352 int ret;
353
354 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ATIME, &gh);
355 ret = gfs2_glock_nq_atime(&gh);
356 if (ret)
357 goto out;
358
359 set_bit(GIF_SW_PAGED, &ip->i_flags);
360 gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks);
361 ret = gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE, &alloc_required);
362 if (ret || !alloc_required)
363 goto out_unlock;
364 ret = -ENOMEM;
365 al = gfs2_alloc_get(ip);
366 if (al == NULL)
367 goto out_unlock;
368
369 ret = gfs2_quota_lock_check(ip);
370 if (ret)
371 goto out_alloc_put;
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 return ret;
415 }
416
417 static struct vm_operations_struct gfs2_vm_ops = {
418 .fault = filemap_fault,
419 .page_mkwrite = gfs2_page_mkwrite,
420 };
421
422
423 /**
424 * gfs2_mmap -
425 * @file: The file to map
426 * @vma: The VMA which described the mapping
427 *
428 * Returns: 0 or error code
429 */
430
431 static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
432 {
433 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
434 struct gfs2_holder i_gh;
435 int error;
436
437 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &i_gh);
438 error = gfs2_glock_nq_atime(&i_gh);
439 if (error) {
440 gfs2_holder_uninit(&i_gh);
441 return error;
442 }
443
444 vma->vm_ops = &gfs2_vm_ops;
445
446 gfs2_glock_dq_uninit(&i_gh);
447
448 return error;
449 }
450
451 /**
452 * gfs2_open - open a file
453 * @inode: the inode to open
454 * @file: the struct file for this opening
455 *
456 * Returns: errno
457 */
458
459 static int gfs2_open(struct inode *inode, struct file *file)
460 {
461 struct gfs2_inode *ip = GFS2_I(inode);
462 struct gfs2_holder i_gh;
463 struct gfs2_file *fp;
464 int error;
465
466 fp = kzalloc(sizeof(struct gfs2_file), GFP_KERNEL);
467 if (!fp)
468 return -ENOMEM;
469
470 mutex_init(&fp->f_fl_mutex);
471
472 gfs2_assert_warn(GFS2_SB(inode), !file->private_data);
473 file->private_data = fp;
474
475 if (S_ISREG(ip->i_inode.i_mode)) {
476 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
477 &i_gh);
478 if (error)
479 goto fail;
480
481 if (!(file->f_flags & O_LARGEFILE) &&
482 ip->i_di.di_size > MAX_NON_LFS) {
483 error = -EOVERFLOW;
484 goto fail_gunlock;
485 }
486
487 gfs2_glock_dq_uninit(&i_gh);
488 }
489
490 return 0;
491
492 fail_gunlock:
493 gfs2_glock_dq_uninit(&i_gh);
494 fail:
495 file->private_data = NULL;
496 kfree(fp);
497 return error;
498 }
499
500 /**
501 * gfs2_close - called to close a struct file
502 * @inode: the inode the struct file belongs to
503 * @file: the struct file being closed
504 *
505 * Returns: errno
506 */
507
508 static int gfs2_close(struct inode *inode, struct file *file)
509 {
510 struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
511 struct gfs2_file *fp;
512
513 fp = file->private_data;
514 file->private_data = NULL;
515
516 if (gfs2_assert_warn(sdp, fp))
517 return -EIO;
518
519 kfree(fp);
520
521 return 0;
522 }
523
524 /**
525 * gfs2_fsync - sync the dirty data for a file (across the cluster)
526 * @file: the file that points to the dentry (we ignore this)
527 * @dentry: the dentry that points to the inode to sync
528 *
529 * The VFS will flush "normal" data for us. We only need to worry
530 * about metadata here. For journaled data, we just do a log flush
531 * as we can't avoid it. Otherwise we can just bale out if datasync
532 * is set. For stuffed inodes we must flush the log in order to
533 * ensure that all data is on disk.
534 *
535 * The call to write_inode_now() is there to write back metadata and
536 * the inode itself. It does also try and write the data, but thats
537 * (hopefully) a no-op due to the VFS having already called filemap_fdatawrite()
538 * for us.
539 *
540 * Returns: errno
541 */
542
543 static int gfs2_fsync(struct file *file, struct dentry *dentry, int datasync)
544 {
545 struct inode *inode = dentry->d_inode;
546 int sync_state = inode->i_state & (I_DIRTY_SYNC|I_DIRTY_DATASYNC);
547 int ret = 0;
548
549 if (gfs2_is_jdata(GFS2_I(inode))) {
550 gfs2_log_flush(GFS2_SB(inode), GFS2_I(inode)->i_gl);
551 return 0;
552 }
553
554 if (sync_state != 0) {
555 if (!datasync)
556 ret = write_inode_now(inode, 0);
557
558 if (gfs2_is_stuffed(GFS2_I(inode)))
559 gfs2_log_flush(GFS2_SB(inode), GFS2_I(inode)->i_gl);
560 }
561
562 return ret;
563 }
564
565 /**
566 * gfs2_setlease - acquire/release a file lease
567 * @file: the file pointer
568 * @arg: lease type
569 * @fl: file lock
570 *
571 * Returns: errno
572 */
573
574 static int gfs2_setlease(struct file *file, long arg, struct file_lock **fl)
575 {
576 struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
577
578 /*
579 * We don't currently have a way to enforce a lease across the whole
580 * cluster; until we do, disable leases (by just returning -EINVAL),
581 * unless the administrator has requested purely local locking.
582 */
583 if (!sdp->sd_args.ar_localflocks)
584 return -EINVAL;
585 return generic_setlease(file, arg, fl);
586 }
587
588 static int gfs2_lm_plock_get(struct gfs2_sbd *sdp, struct lm_lockname *name,
589 struct file *file, struct file_lock *fl)
590 {
591 int error = -EIO;
592 if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
593 error = sdp->sd_lockstruct.ls_ops->lm_plock_get(
594 sdp->sd_lockstruct.ls_lockspace, name, file, fl);
595 return error;
596 }
597
598 static int gfs2_lm_plock(struct gfs2_sbd *sdp, struct lm_lockname *name,
599 struct file *file, int cmd, struct file_lock *fl)
600 {
601 int error = -EIO;
602 if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
603 error = sdp->sd_lockstruct.ls_ops->lm_plock(
604 sdp->sd_lockstruct.ls_lockspace, name, file, cmd, fl);
605 return error;
606 }
607
608 static int gfs2_lm_punlock(struct gfs2_sbd *sdp, struct lm_lockname *name,
609 struct file *file, struct file_lock *fl)
610 {
611 int error = -EIO;
612 if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
613 error = sdp->sd_lockstruct.ls_ops->lm_punlock(
614 sdp->sd_lockstruct.ls_lockspace, name, file, fl);
615 return error;
616 }
617
618 /**
619 * gfs2_lock - acquire/release a posix lock on a file
620 * @file: the file pointer
621 * @cmd: either modify or retrieve lock state, possibly wait
622 * @fl: type and range of lock
623 *
624 * Returns: errno
625 */
626
627 static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
628 {
629 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
630 struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
631 struct lm_lockname name =
632 { .ln_number = ip->i_no_addr,
633 .ln_type = LM_TYPE_PLOCK };
634
635 if (!(fl->fl_flags & FL_POSIX))
636 return -ENOLCK;
637 if (__mandatory_lock(&ip->i_inode))
638 return -ENOLCK;
639
640 if (cmd == F_CANCELLK) {
641 /* Hack: */
642 cmd = F_SETLK;
643 fl->fl_type = F_UNLCK;
644 }
645 if (IS_GETLK(cmd))
646 return gfs2_lm_plock_get(sdp, &name, file, fl);
647 else if (fl->fl_type == F_UNLCK)
648 return gfs2_lm_punlock(sdp, &name, file, fl);
649 else
650 return gfs2_lm_plock(sdp, &name, file, cmd, fl);
651 }
652
653 static int do_flock(struct file *file, int cmd, struct file_lock *fl)
654 {
655 struct gfs2_file *fp = file->private_data;
656 struct gfs2_holder *fl_gh = &fp->f_fl_gh;
657 struct gfs2_inode *ip = GFS2_I(file->f_path.dentry->d_inode);
658 struct gfs2_glock *gl;
659 unsigned int state;
660 int flags;
661 int error = 0;
662
663 state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
664 flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE;
665
666 mutex_lock(&fp->f_fl_mutex);
667
668 gl = fl_gh->gh_gl;
669 if (gl) {
670 if (fl_gh->gh_state == state)
671 goto out;
672 flock_lock_file_wait(file,
673 &(struct file_lock){.fl_type = F_UNLCK});
674 gfs2_glock_dq_wait(fl_gh);
675 gfs2_holder_reinit(state, flags, fl_gh);
676 } else {
677 error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr,
678 &gfs2_flock_glops, CREATE, &gl);
679 if (error)
680 goto out;
681 gfs2_holder_init(gl, state, flags, fl_gh);
682 gfs2_glock_put(gl);
683 }
684 error = gfs2_glock_nq(fl_gh);
685 if (error) {
686 gfs2_holder_uninit(fl_gh);
687 if (error == GLR_TRYFAILED)
688 error = -EAGAIN;
689 } else {
690 error = flock_lock_file_wait(file, fl);
691 gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error);
692 }
693
694 out:
695 mutex_unlock(&fp->f_fl_mutex);
696 return error;
697 }
698
699 static void do_unflock(struct file *file, struct file_lock *fl)
700 {
701 struct gfs2_file *fp = file->private_data;
702 struct gfs2_holder *fl_gh = &fp->f_fl_gh;
703
704 mutex_lock(&fp->f_fl_mutex);
705 flock_lock_file_wait(file, fl);
706 if (fl_gh->gh_gl)
707 gfs2_glock_dq_uninit(fl_gh);
708 mutex_unlock(&fp->f_fl_mutex);
709 }
710
711 /**
712 * gfs2_flock - acquire/release a flock lock on a file
713 * @file: the file pointer
714 * @cmd: either modify or retrieve lock state, possibly wait
715 * @fl: type and range of lock
716 *
717 * Returns: errno
718 */
719
720 static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl)
721 {
722 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
723
724 if (!(fl->fl_flags & FL_FLOCK))
725 return -ENOLCK;
726 if (__mandatory_lock(&ip->i_inode))
727 return -ENOLCK;
728
729 if (fl->fl_type == F_UNLCK) {
730 do_unflock(file, fl);
731 return 0;
732 } else {
733 return do_flock(file, cmd, fl);
734 }
735 }
736
737 const struct file_operations gfs2_file_fops = {
738 .llseek = gfs2_llseek,
739 .read = do_sync_read,
740 .aio_read = generic_file_aio_read,
741 .write = do_sync_write,
742 .aio_write = generic_file_aio_write,
743 .unlocked_ioctl = gfs2_ioctl,
744 .mmap = gfs2_mmap,
745 .open = gfs2_open,
746 .release = gfs2_close,
747 .fsync = gfs2_fsync,
748 .lock = gfs2_lock,
749 .flock = gfs2_flock,
750 .splice_read = generic_file_splice_read,
751 .splice_write = generic_file_splice_write,
752 .setlease = gfs2_setlease,
753 };
754
755 const struct file_operations gfs2_dir_fops = {
756 .readdir = gfs2_readdir,
757 .unlocked_ioctl = gfs2_ioctl,
758 .open = gfs2_open,
759 .release = gfs2_close,
760 .fsync = gfs2_fsync,
761 .lock = gfs2_lock,
762 .flock = gfs2_flock,
763 };
764
765 const struct file_operations gfs2_file_fops_nolock = {
766 .llseek = gfs2_llseek,
767 .read = do_sync_read,
768 .aio_read = generic_file_aio_read,
769 .write = do_sync_write,
770 .aio_write = generic_file_aio_write,
771 .unlocked_ioctl = gfs2_ioctl,
772 .mmap = gfs2_mmap,
773 .open = gfs2_open,
774 .release = gfs2_close,
775 .fsync = gfs2_fsync,
776 .splice_read = generic_file_splice_read,
777 .splice_write = generic_file_splice_write,
778 .setlease = gfs2_setlease,
779 };
780
781 const struct file_operations gfs2_dir_fops_nolock = {
782 .readdir = gfs2_readdir,
783 .unlocked_ioctl = gfs2_ioctl,
784 .open = gfs2_open,
785 .release = gfs2_close,
786 .fsync = gfs2_fsync,
787 };
788
Support for the Chinese Samsung S3C2440 based development boards