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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/falloc.h>
22#include <linux/swap.h>
23#include <linux/crc32.h>
24#include <linux/writeback.h>
25#include <linux/uaccess.h>
26#include <linux/dlm.h>
27#include <linux/dlm_plock.h>
28#include <linux/delay.h>
29
30#include "gfs2.h"
31#include "incore.h"
32#include "bmap.h"
33#include "dir.h"
34#include "glock.h"
35#include "glops.h"
36#include "inode.h"
37#include "log.h"
38#include "meta_io.h"
39#include "quota.h"
40#include "rgrp.h"
41#include "trans.h"
42#include "util.h"
43
44/**
45 * gfs2_llseek - seek to a location in a file
46 * @file: the file
47 * @offset: the offset
48 * @whence: 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
56static loff_t gfs2_llseek(struct file *file, loff_t offset, int whence)
57{
58 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
59 struct gfs2_holder i_gh;
60 loff_t error;
61
62 switch (whence) {
63 case SEEK_END: /* These reference inode->i_size */
64 case SEEK_DATA:
65 case SEEK_HOLE:
66 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
67 &i_gh);
68 if (!error) {
69 error = generic_file_llseek(file, offset, whence);
70 gfs2_glock_dq_uninit(&i_gh);
71 }
72 break;
73 case SEEK_CUR:
74 case SEEK_SET:
75 error = generic_file_llseek(file, offset, whence);
76 break;
77 default:
78 error = -EINVAL;
79 }
80
81 return error;
82}
83
84/**
85 * gfs2_readdir - Iterator for a directory
86 * @file: The directory to read from
87 * @ctx: What to feed directory entries to
88 *
89 * Returns: errno
90 */
91
92static int gfs2_readdir(struct file *file, struct dir_context *ctx)
93{
94 struct inode *dir = file->f_mapping->host;
95 struct gfs2_inode *dip = GFS2_I(dir);
96 struct gfs2_holder d_gh;
97 int error;
98
99 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
100 if (error)
101 return error;
102
103 error = gfs2_dir_read(dir, ctx, &file->f_ra);
104
105 gfs2_glock_dq_uninit(&d_gh);
106
107 return error;
108}
109
110/**
111 * fsflags_cvt
112 * @table: A table of 32 u32 flags
113 * @val: a 32 bit value to convert
114 *
115 * This function can be used to convert between fsflags values and
116 * GFS2's own flags values.
117 *
118 * Returns: the converted flags
119 */
120static u32 fsflags_cvt(const u32 *table, u32 val)
121{
122 u32 res = 0;
123 while(val) {
124 if (val & 1)
125 res |= *table;
126 table++;
127 val >>= 1;
128 }
129 return res;
130}
131
132static const u32 fsflags_to_gfs2[32] = {
133 [3] = GFS2_DIF_SYNC,
134 [4] = GFS2_DIF_IMMUTABLE,
135 [5] = GFS2_DIF_APPENDONLY,
136 [7] = GFS2_DIF_NOATIME,
137 [12] = GFS2_DIF_EXHASH,
138 [14] = GFS2_DIF_INHERIT_JDATA,
139 [17] = GFS2_DIF_TOPDIR,
140};
141
142static const u32 gfs2_to_fsflags[32] = {
143 [gfs2fl_Sync] = FS_SYNC_FL,
144 [gfs2fl_Immutable] = FS_IMMUTABLE_FL,
145 [gfs2fl_AppendOnly] = FS_APPEND_FL,
146 [gfs2fl_NoAtime] = FS_NOATIME_FL,
147 [gfs2fl_ExHash] = FS_INDEX_FL,
148 [gfs2fl_TopLevel] = FS_TOPDIR_FL,
149 [gfs2fl_InheritJdata] = FS_JOURNAL_DATA_FL,
150};
151
152static int gfs2_get_flags(struct file *filp, u32 __user *ptr)
153{
154 struct inode *inode = file_inode(filp);
155 struct gfs2_inode *ip = GFS2_I(inode);
156 struct gfs2_holder gh;
157 int error;
158 u32 fsflags;
159
160 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
161 error = gfs2_glock_nq(&gh);
162 if (error)
163 goto out_uninit;
164
165 fsflags = fsflags_cvt(gfs2_to_fsflags, ip->i_diskflags);
166 if (!S_ISDIR(inode->i_mode) && ip->i_diskflags & GFS2_DIF_JDATA)
167 fsflags |= FS_JOURNAL_DATA_FL;
168 if (put_user(fsflags, ptr))
169 error = -EFAULT;
170
171 gfs2_glock_dq(&gh);
172out_uninit:
173 gfs2_holder_uninit(&gh);
174 return error;
175}
176
177void gfs2_set_inode_flags(struct inode *inode)
178{
179 struct gfs2_inode *ip = GFS2_I(inode);
180 unsigned int flags = inode->i_flags;
181
182 flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC|S_NOSEC);
183 if ((ip->i_eattr == 0) && !is_sxid(inode->i_mode))
184 flags |= S_NOSEC;
185 if (ip->i_diskflags & GFS2_DIF_IMMUTABLE)
186 flags |= S_IMMUTABLE;
187 if (ip->i_diskflags & GFS2_DIF_APPENDONLY)
188 flags |= S_APPEND;
189 if (ip->i_diskflags & GFS2_DIF_NOATIME)
190 flags |= S_NOATIME;
191 if (ip->i_diskflags & GFS2_DIF_SYNC)
192 flags |= S_SYNC;
193 inode->i_flags = flags;
194}
195
196/* Flags that can be set by user space */
197#define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA| \
198 GFS2_DIF_IMMUTABLE| \
199 GFS2_DIF_APPENDONLY| \
200 GFS2_DIF_NOATIME| \
201 GFS2_DIF_SYNC| \
202 GFS2_DIF_SYSTEM| \
203 GFS2_DIF_TOPDIR| \
204 GFS2_DIF_INHERIT_JDATA)
205
206/**
207 * do_gfs2_set_flags - set flags on an inode
208 * @filp: file pointer
209 * @reqflags: The flags to set
210 * @mask: Indicates which flags are valid
211 *
212 */
213static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask)
214{
215 struct inode *inode = file_inode(filp);
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 = mnt_want_write_file(filp);
224 if (error)
225 return error;
226
227 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
228 if (error)
229 goto out_drop_write;
230
231 error = -EACCES;
232 if (!inode_owner_or_capable(inode))
233 goto out;
234
235 error = 0;
236 flags = ip->i_diskflags;
237 new_flags = (flags & ~mask) | (reqflags & mask);
238 if ((new_flags ^ flags) == 0)
239 goto out;
240
241 error = -EINVAL;
242 if ((new_flags ^ flags) & ~GFS2_FLAGS_USER_SET)
243 goto out;
244
245 error = -EPERM;
246 if (IS_IMMUTABLE(inode) && (new_flags & GFS2_DIF_IMMUTABLE))
247 goto out;
248 if (IS_APPEND(inode) && (new_flags & GFS2_DIF_APPENDONLY))
249 goto out;
250 if (((new_flags ^ flags) & GFS2_DIF_IMMUTABLE) &&
251 !capable(CAP_LINUX_IMMUTABLE))
252 goto out;
253 if (!IS_IMMUTABLE(inode)) {
254 error = gfs2_permission(inode, MAY_WRITE);
255 if (error)
256 goto out;
257 }
258 if ((flags ^ new_flags) & GFS2_DIF_JDATA) {
259 if (flags & GFS2_DIF_JDATA)
260 gfs2_log_flush(sdp, ip->i_gl, NORMAL_FLUSH);
261 error = filemap_fdatawrite(inode->i_mapping);
262 if (error)
263 goto out;
264 error = filemap_fdatawait(inode->i_mapping);
265 if (error)
266 goto out;
267 }
268 error = gfs2_trans_begin(sdp, RES_DINODE, 0);
269 if (error)
270 goto out;
271 error = gfs2_meta_inode_buffer(ip, &bh);
272 if (error)
273 goto out_trans_end;
274 gfs2_trans_add_meta(ip->i_gl, bh);
275 ip->i_diskflags = new_flags;
276 gfs2_dinode_out(ip, bh->b_data);
277 brelse(bh);
278 gfs2_set_inode_flags(inode);
279 gfs2_set_aops(inode);
280out_trans_end:
281 gfs2_trans_end(sdp);
282out:
283 gfs2_glock_dq_uninit(&gh);
284out_drop_write:
285 mnt_drop_write_file(filp);
286 return error;
287}
288
289static int gfs2_set_flags(struct file *filp, u32 __user *ptr)
290{
291 struct inode *inode = file_inode(filp);
292 u32 fsflags, gfsflags;
293
294 if (get_user(fsflags, ptr))
295 return -EFAULT;
296
297 gfsflags = fsflags_cvt(fsflags_to_gfs2, fsflags);
298 if (!S_ISDIR(inode->i_mode)) {
299 gfsflags &= ~GFS2_DIF_TOPDIR;
300 if (gfsflags & GFS2_DIF_INHERIT_JDATA)
301 gfsflags ^= (GFS2_DIF_JDATA | GFS2_DIF_INHERIT_JDATA);
302 return do_gfs2_set_flags(filp, gfsflags, ~GFS2_DIF_SYSTEM);
303 }
304 return do_gfs2_set_flags(filp, gfsflags, ~(GFS2_DIF_SYSTEM | GFS2_DIF_JDATA));
305}
306
307static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
308{
309 switch(cmd) {
310 case FS_IOC_GETFLAGS:
311 return gfs2_get_flags(filp, (u32 __user *)arg);
312 case FS_IOC_SETFLAGS:
313 return gfs2_set_flags(filp, (u32 __user *)arg);
314 case FITRIM:
315 return gfs2_fitrim(filp, (void __user *)arg);
316 }
317 return -ENOTTY;
318}
319
320/**
321 * gfs2_size_hint - Give a hint to the size of a write request
322 * @filep: The struct file
323 * @offset: The file offset of the write
324 * @size: The length of the write
325 *
326 * When we are about to do a write, this function records the total
327 * write size in order to provide a suitable hint to the lower layers
328 * about how many blocks will be required.
329 *
330 */
331
332static void gfs2_size_hint(struct file *filep, loff_t offset, size_t size)
333{
334 struct inode *inode = file_inode(filep);
335 struct gfs2_sbd *sdp = GFS2_SB(inode);
336 struct gfs2_inode *ip = GFS2_I(inode);
337 size_t blks = (size + sdp->sd_sb.sb_bsize - 1) >> sdp->sd_sb.sb_bsize_shift;
338 int hint = min_t(size_t, INT_MAX, blks);
339
340 if (hint > atomic_read(&ip->i_res.rs_sizehint))
341 atomic_set(&ip->i_res.rs_sizehint, hint);
342}
343
344/**
345 * gfs2_allocate_page_backing - Use bmap to allocate blocks
346 * @page: The (locked) page to allocate backing for
347 *
348 * We try to allocate all the blocks required for the page in
349 * one go. This might fail for various reasons, so we keep
350 * trying until all the blocks to back this page are allocated.
351 * If some of the blocks are already allocated, thats ok too.
352 */
353
354static int gfs2_allocate_page_backing(struct page *page)
355{
356 struct inode *inode = page->mapping->host;
357 struct buffer_head bh;
358 unsigned long size = PAGE_SIZE;
359 u64 lblock = page->index << (PAGE_SHIFT - inode->i_blkbits);
360
361 do {
362 bh.b_state = 0;
363 bh.b_size = size;
364 gfs2_block_map(inode, lblock, &bh, 1);
365 if (!buffer_mapped(&bh))
366 return -EIO;
367 size -= bh.b_size;
368 lblock += (bh.b_size >> inode->i_blkbits);
369 } while(size > 0);
370 return 0;
371}
372
373/**
374 * gfs2_page_mkwrite - Make a shared, mmap()ed, page writable
375 * @vma: The virtual memory area
376 * @vmf: The virtual memory fault containing the page to become writable
377 *
378 * When the page becomes writable, we need to ensure that we have
379 * blocks allocated on disk to back that page.
380 */
381
382static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
383{
384 struct page *page = vmf->page;
385 struct inode *inode = file_inode(vma->vm_file);
386 struct gfs2_inode *ip = GFS2_I(inode);
387 struct gfs2_sbd *sdp = GFS2_SB(inode);
388 struct gfs2_alloc_parms ap = { .aflags = 0, };
389 unsigned long last_index;
390 u64 pos = page->index << PAGE_SHIFT;
391 unsigned int data_blocks, ind_blocks, rblocks;
392 struct gfs2_holder gh;
393 loff_t size;
394 int ret;
395
396 sb_start_pagefault(inode->i_sb);
397
398 ret = gfs2_rsqa_alloc(ip);
399 if (ret)
400 goto out;
401
402 gfs2_size_hint(vma->vm_file, pos, PAGE_SIZE);
403
404 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
405 ret = gfs2_glock_nq(&gh);
406 if (ret)
407 goto out_uninit;
408
409 /* Update file times before taking page lock */
410 file_update_time(vma->vm_file);
411
412 set_bit(GLF_DIRTY, &ip->i_gl->gl_flags);
413 set_bit(GIF_SW_PAGED, &ip->i_flags);
414
415 if (!gfs2_write_alloc_required(ip, pos, PAGE_SIZE)) {
416 lock_page(page);
417 if (!PageUptodate(page) || page->mapping != inode->i_mapping) {
418 ret = -EAGAIN;
419 unlock_page(page);
420 }
421 goto out_unlock;
422 }
423
424 ret = gfs2_rindex_update(sdp);
425 if (ret)
426 goto out_unlock;
427
428 gfs2_write_calc_reserv(ip, PAGE_SIZE, &data_blocks, &ind_blocks);
429 ap.target = data_blocks + ind_blocks;
430 ret = gfs2_quota_lock_check(ip, &ap);
431 if (ret)
432 goto out_unlock;
433 ret = gfs2_inplace_reserve(ip, &ap);
434 if (ret)
435 goto out_quota_unlock;
436
437 rblocks = RES_DINODE + ind_blocks;
438 if (gfs2_is_jdata(ip))
439 rblocks += data_blocks ? data_blocks : 1;
440 if (ind_blocks || data_blocks) {
441 rblocks += RES_STATFS + RES_QUOTA;
442 rblocks += gfs2_rg_blocks(ip, data_blocks + ind_blocks);
443 }
444 ret = gfs2_trans_begin(sdp, rblocks, 0);
445 if (ret)
446 goto out_trans_fail;
447
448 lock_page(page);
449 ret = -EINVAL;
450 size = i_size_read(inode);
451 last_index = (size - 1) >> PAGE_SHIFT;
452 /* Check page index against inode size */
453 if (size == 0 || (page->index > last_index))
454 goto out_trans_end;
455
456 ret = -EAGAIN;
457 /* If truncated, we must retry the operation, we may have raced
458 * with the glock demotion code.
459 */
460 if (!PageUptodate(page) || page->mapping != inode->i_mapping)
461 goto out_trans_end;
462
463 /* Unstuff, if required, and allocate backing blocks for page */
464 ret = 0;
465 if (gfs2_is_stuffed(ip))
466 ret = gfs2_unstuff_dinode(ip, page);
467 if (ret == 0)
468 ret = gfs2_allocate_page_backing(page);
469
470out_trans_end:
471 if (ret)
472 unlock_page(page);
473 gfs2_trans_end(sdp);
474out_trans_fail:
475 gfs2_inplace_release(ip);
476out_quota_unlock:
477 gfs2_quota_unlock(ip);
478out_unlock:
479 gfs2_glock_dq(&gh);
480out_uninit:
481 gfs2_holder_uninit(&gh);
482 if (ret == 0) {
483 set_page_dirty(page);
484 wait_for_stable_page(page);
485 }
486out:
487 sb_end_pagefault(inode->i_sb);
488 return block_page_mkwrite_return(ret);
489}
490
491static const struct vm_operations_struct gfs2_vm_ops = {
492 .fault = filemap_fault,
493 .map_pages = filemap_map_pages,
494 .page_mkwrite = gfs2_page_mkwrite,
495};
496
497/**
498 * gfs2_mmap -
499 * @file: The file to map
500 * @vma: The VMA which described the mapping
501 *
502 * There is no need to get a lock here unless we should be updating
503 * atime. We ignore any locking errors since the only consequence is
504 * a missed atime update (which will just be deferred until later).
505 *
506 * Returns: 0
507 */
508
509static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
510{
511 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
512
513 if (!(file->f_flags & O_NOATIME) &&
514 !IS_NOATIME(&ip->i_inode)) {
515 struct gfs2_holder i_gh;
516 int error;
517
518 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
519 &i_gh);
520 if (error)
521 return error;
522 /* grab lock to update inode */
523 gfs2_glock_dq_uninit(&i_gh);
524 file_accessed(file);
525 }
526 vma->vm_ops = &gfs2_vm_ops;
527
528 return 0;
529}
530
531/**
532 * gfs2_open_common - This is common to open and atomic_open
533 * @inode: The inode being opened
534 * @file: The file being opened
535 *
536 * This maybe called under a glock or not depending upon how it has
537 * been called. We must always be called under a glock for regular
538 * files, however. For other file types, it does not matter whether
539 * we hold the glock or not.
540 *
541 * Returns: Error code or 0 for success
542 */
543
544int gfs2_open_common(struct inode *inode, struct file *file)
545{
546 struct gfs2_file *fp;
547 int ret;
548
549 if (S_ISREG(inode->i_mode)) {
550 ret = generic_file_open(inode, file);
551 if (ret)
552 return ret;
553 }
554
555 fp = kzalloc(sizeof(struct gfs2_file), GFP_NOFS);
556 if (!fp)
557 return -ENOMEM;
558
559 mutex_init(&fp->f_fl_mutex);
560
561 gfs2_assert_warn(GFS2_SB(inode), !file->private_data);
562 file->private_data = fp;
563 return 0;
564}
565
566/**
567 * gfs2_open - open a file
568 * @inode: the inode to open
569 * @file: the struct file for this opening
570 *
571 * After atomic_open, this function is only used for opening files
572 * which are already cached. We must still get the glock for regular
573 * files to ensure that we have the file size uptodate for the large
574 * file check which is in the common code. That is only an issue for
575 * regular files though.
576 *
577 * Returns: errno
578 */
579
580static int gfs2_open(struct inode *inode, struct file *file)
581{
582 struct gfs2_inode *ip = GFS2_I(inode);
583 struct gfs2_holder i_gh;
584 int error;
585 bool need_unlock = false;
586
587 if (S_ISREG(ip->i_inode.i_mode)) {
588 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
589 &i_gh);
590 if (error)
591 return error;
592 need_unlock = true;
593 }
594
595 error = gfs2_open_common(inode, file);
596
597 if (need_unlock)
598 gfs2_glock_dq_uninit(&i_gh);
599
600 return error;
601}
602
603/**
604 * gfs2_release - called to close a struct file
605 * @inode: the inode the struct file belongs to
606 * @file: the struct file being closed
607 *
608 * Returns: errno
609 */
610
611static int gfs2_release(struct inode *inode, struct file *file)
612{
613 struct gfs2_inode *ip = GFS2_I(inode);
614
615 kfree(file->private_data);
616 file->private_data = NULL;
617
618 if (!(file->f_mode & FMODE_WRITE))
619 return 0;
620
621 gfs2_rsqa_delete(ip, &inode->i_writecount);
622 return 0;
623}
624
625/**
626 * gfs2_fsync - sync the dirty data for a file (across the cluster)
627 * @file: the file that points to the dentry
628 * @start: the start position in the file to sync
629 * @end: the end position in the file to sync
630 * @datasync: set if we can ignore timestamp changes
631 *
632 * We split the data flushing here so that we don't wait for the data
633 * until after we've also sent the metadata to disk. Note that for
634 * data=ordered, we will write & wait for the data at the log flush
635 * stage anyway, so this is unlikely to make much of a difference
636 * except in the data=writeback case.
637 *
638 * If the fdatawrite fails due to any reason except -EIO, we will
639 * continue the remainder of the fsync, although we'll still report
640 * the error at the end. This is to match filemap_write_and_wait_range()
641 * behaviour.
642 *
643 * Returns: errno
644 */
645
646static int gfs2_fsync(struct file *file, loff_t start, loff_t end,
647 int datasync)
648{
649 struct address_space *mapping = file->f_mapping;
650 struct inode *inode = mapping->host;
651 int sync_state = inode->i_state & I_DIRTY_ALL;
652 struct gfs2_inode *ip = GFS2_I(inode);
653 int ret = 0, ret1 = 0;
654
655 if (mapping->nrpages) {
656 ret1 = filemap_fdatawrite_range(mapping, start, end);
657 if (ret1 == -EIO)
658 return ret1;
659 }
660
661 if (!gfs2_is_jdata(ip))
662 sync_state &= ~I_DIRTY_PAGES;
663 if (datasync)
664 sync_state &= ~(I_DIRTY_SYNC | I_DIRTY_TIME);
665
666 if (sync_state) {
667 ret = sync_inode_metadata(inode, 1);
668 if (ret)
669 return ret;
670 if (gfs2_is_jdata(ip))
671 filemap_write_and_wait(mapping);
672 gfs2_ail_flush(ip->i_gl, 1);
673 }
674
675 if (mapping->nrpages)
676 ret = filemap_fdatawait_range(mapping, start, end);
677
678 return ret ? ret : ret1;
679}
680
681/**
682 * gfs2_file_write_iter - Perform a write to a file
683 * @iocb: The io context
684 * @iov: The data to write
685 * @nr_segs: Number of @iov segments
686 * @pos: The file position
687 *
688 * We have to do a lock/unlock here to refresh the inode size for
689 * O_APPEND writes, otherwise we can land up writing at the wrong
690 * offset. There is still a race, but provided the app is using its
691 * own file locking, this will make O_APPEND work as expected.
692 *
693 */
694
695static ssize_t gfs2_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
696{
697 struct file *file = iocb->ki_filp;
698 struct gfs2_inode *ip = GFS2_I(file_inode(file));
699 int ret;
700
701 ret = gfs2_rsqa_alloc(ip);
702 if (ret)
703 return ret;
704
705 gfs2_size_hint(file, iocb->ki_pos, iov_iter_count(from));
706
707 if (iocb->ki_flags & IOCB_APPEND) {
708 struct gfs2_holder gh;
709
710 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
711 if (ret)
712 return ret;
713 gfs2_glock_dq_uninit(&gh);
714 }
715
716 return generic_file_write_iter(iocb, from);
717}
718
719static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len,
720 int mode)
721{
722 struct gfs2_inode *ip = GFS2_I(inode);
723 struct buffer_head *dibh;
724 int error;
725 unsigned int nr_blks;
726 sector_t lblock = offset >> inode->i_blkbits;
727
728 error = gfs2_meta_inode_buffer(ip, &dibh);
729 if (unlikely(error))
730 return error;
731
732 gfs2_trans_add_meta(ip->i_gl, dibh);
733
734 if (gfs2_is_stuffed(ip)) {
735 error = gfs2_unstuff_dinode(ip, NULL);
736 if (unlikely(error))
737 goto out;
738 }
739
740 while (len) {
741 struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
742 bh_map.b_size = len;
743 set_buffer_zeronew(&bh_map);
744
745 error = gfs2_block_map(inode, lblock, &bh_map, 1);
746 if (unlikely(error))
747 goto out;
748 len -= bh_map.b_size;
749 nr_blks = bh_map.b_size >> inode->i_blkbits;
750 lblock += nr_blks;
751 if (!buffer_new(&bh_map))
752 continue;
753 if (unlikely(!buffer_zeronew(&bh_map))) {
754 error = -EIO;
755 goto out;
756 }
757 }
758out:
759 brelse(dibh);
760 return error;
761}
762/**
763 * calc_max_reserv() - Reverse of write_calc_reserv. Given a number of
764 * blocks, determine how many bytes can be written.
765 * @ip: The inode in question.
766 * @len: Max cap of bytes. What we return in *len must be <= this.
767 * @data_blocks: Compute and return the number of data blocks needed
768 * @ind_blocks: Compute and return the number of indirect blocks needed
769 * @max_blocks: The total blocks available to work with.
770 *
771 * Returns: void, but @len, @data_blocks and @ind_blocks are filled in.
772 */
773static void calc_max_reserv(struct gfs2_inode *ip, loff_t *len,
774 unsigned int *data_blocks, unsigned int *ind_blocks,
775 unsigned int max_blocks)
776{
777 loff_t max = *len;
778 const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
779 unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1);
780
781 for (tmp = max_data; tmp > sdp->sd_diptrs;) {
782 tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
783 max_data -= tmp;
784 }
785
786 *data_blocks = max_data;
787 *ind_blocks = max_blocks - max_data;
788 *len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift;
789 if (*len > max) {
790 *len = max;
791 gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks);
792 }
793}
794
795static long __gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
796{
797 struct inode *inode = file_inode(file);
798 struct gfs2_sbd *sdp = GFS2_SB(inode);
799 struct gfs2_inode *ip = GFS2_I(inode);
800 struct gfs2_alloc_parms ap = { .aflags = 0, };
801 unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
802 loff_t bytes, max_bytes, max_blks = UINT_MAX;
803 int error;
804 const loff_t pos = offset;
805 const loff_t count = len;
806 loff_t bsize_mask = ~((loff_t)sdp->sd_sb.sb_bsize - 1);
807 loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift;
808 loff_t max_chunk_size = UINT_MAX & bsize_mask;
809
810 next = (next + 1) << sdp->sd_sb.sb_bsize_shift;
811
812 offset &= bsize_mask;
813
814 len = next - offset;
815 bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2;
816 if (!bytes)
817 bytes = UINT_MAX;
818 bytes &= bsize_mask;
819 if (bytes == 0)
820 bytes = sdp->sd_sb.sb_bsize;
821
822 gfs2_size_hint(file, offset, len);
823
824 gfs2_write_calc_reserv(ip, PAGE_SIZE, &data_blocks, &ind_blocks);
825 ap.min_target = data_blocks + ind_blocks;
826
827 while (len > 0) {
828 if (len < bytes)
829 bytes = len;
830 if (!gfs2_write_alloc_required(ip, offset, bytes)) {
831 len -= bytes;
832 offset += bytes;
833 continue;
834 }
835
836 /* We need to determine how many bytes we can actually
837 * fallocate without exceeding quota or going over the
838 * end of the fs. We start off optimistically by assuming
839 * we can write max_bytes */
840 max_bytes = (len > max_chunk_size) ? max_chunk_size : len;
841
842 /* Since max_bytes is most likely a theoretical max, we
843 * calculate a more realistic 'bytes' to serve as a good
844 * starting point for the number of bytes we may be able
845 * to write */
846 gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks);
847 ap.target = data_blocks + ind_blocks;
848
849 error = gfs2_quota_lock_check(ip, &ap);
850 if (error)
851 return error;
852 /* ap.allowed tells us how many blocks quota will allow
853 * us to write. Check if this reduces max_blks */
854 if (ap.allowed && ap.allowed < max_blks)
855 max_blks = ap.allowed;
856
857 error = gfs2_inplace_reserve(ip, &ap);
858 if (error)
859 goto out_qunlock;
860
861 /* check if the selected rgrp limits our max_blks further */
862 if (ap.allowed && ap.allowed < max_blks)
863 max_blks = ap.allowed;
864
865 /* Almost done. Calculate bytes that can be written using
866 * max_blks. We also recompute max_bytes, data_blocks and
867 * ind_blocks */
868 calc_max_reserv(ip, &max_bytes, &data_blocks,
869 &ind_blocks, max_blks);
870
871 rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA +
872 RES_RG_HDR + gfs2_rg_blocks(ip, data_blocks + ind_blocks);
873 if (gfs2_is_jdata(ip))
874 rblocks += data_blocks ? data_blocks : 1;
875
876 error = gfs2_trans_begin(sdp, rblocks,
877 PAGE_SIZE/sdp->sd_sb.sb_bsize);
878 if (error)
879 goto out_trans_fail;
880
881 error = fallocate_chunk(inode, offset, max_bytes, mode);
882 gfs2_trans_end(sdp);
883
884 if (error)
885 goto out_trans_fail;
886
887 len -= max_bytes;
888 offset += max_bytes;
889 gfs2_inplace_release(ip);
890 gfs2_quota_unlock(ip);
891 }
892
893 if (!(mode & FALLOC_FL_KEEP_SIZE) && (pos + count) > inode->i_size) {
894 i_size_write(inode, pos + count);
895 file_update_time(file);
896 mark_inode_dirty(inode);
897 }
898
899 if ((file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host))
900 return vfs_fsync_range(file, pos, pos + count - 1,
901 (file->f_flags & __O_SYNC) ? 0 : 1);
902 return 0;
903
904out_trans_fail:
905 gfs2_inplace_release(ip);
906out_qunlock:
907 gfs2_quota_unlock(ip);
908 return error;
909}
910
911static long gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
912{
913 struct inode *inode = file_inode(file);
914 struct gfs2_inode *ip = GFS2_I(inode);
915 struct gfs2_holder gh;
916 int ret;
917
918 if ((mode & ~FALLOC_FL_KEEP_SIZE) || gfs2_is_jdata(ip))
919 return -EOPNOTSUPP;
920
921 inode_lock(inode);
922
923 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
924 ret = gfs2_glock_nq(&gh);
925 if (ret)
926 goto out_uninit;
927
928 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
929 (offset + len) > inode->i_size) {
930 ret = inode_newsize_ok(inode, offset + len);
931 if (ret)
932 goto out_unlock;
933 }
934
935 ret = get_write_access(inode);
936 if (ret)
937 goto out_unlock;
938
939 ret = gfs2_rsqa_alloc(ip);
940 if (ret)
941 goto out_putw;
942
943 ret = __gfs2_fallocate(file, mode, offset, len);
944 if (ret)
945 gfs2_rs_deltree(&ip->i_res);
946
947out_putw:
948 put_write_access(inode);
949out_unlock:
950 gfs2_glock_dq(&gh);
951out_uninit:
952 gfs2_holder_uninit(&gh);
953 inode_unlock(inode);
954 return ret;
955}
956
957static ssize_t gfs2_file_splice_write(struct pipe_inode_info *pipe,
958 struct file *out, loff_t *ppos,
959 size_t len, unsigned int flags)
960{
961 int error;
962 struct gfs2_inode *ip = GFS2_I(out->f_mapping->host);
963
964 error = gfs2_rsqa_alloc(ip);
965 if (error)
966 return (ssize_t)error;
967
968 gfs2_size_hint(out, *ppos, len);
969
970 return iter_file_splice_write(pipe, out, ppos, len, flags);
971}
972
973#ifdef CONFIG_GFS2_FS_LOCKING_DLM
974
975/**
976 * gfs2_lock - acquire/release a posix lock on a file
977 * @file: the file pointer
978 * @cmd: either modify or retrieve lock state, possibly wait
979 * @fl: type and range of lock
980 *
981 * Returns: errno
982 */
983
984static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
985{
986 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
987 struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
988 struct lm_lockstruct *ls = &sdp->sd_lockstruct;
989
990 if (!(fl->fl_flags & FL_POSIX))
991 return -ENOLCK;
992 if (__mandatory_lock(&ip->i_inode) && fl->fl_type != F_UNLCK)
993 return -ENOLCK;
994
995 if (cmd == F_CANCELLK) {
996 /* Hack: */
997 cmd = F_SETLK;
998 fl->fl_type = F_UNLCK;
999 }
1000 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) {
1001 if (fl->fl_type == F_UNLCK)
1002 locks_lock_file_wait(file, fl);
1003 return -EIO;
1004 }
1005 if (IS_GETLK(cmd))
1006 return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl);
1007 else if (fl->fl_type == F_UNLCK)
1008 return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl);
1009 else
1010 return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl);
1011}
1012
1013static int do_flock(struct file *file, int cmd, struct file_lock *fl)
1014{
1015 struct gfs2_file *fp = file->private_data;
1016 struct gfs2_holder *fl_gh = &fp->f_fl_gh;
1017 struct gfs2_inode *ip = GFS2_I(file_inode(file));
1018 struct gfs2_glock *gl;
1019 unsigned int state;
1020 u16 flags;
1021 int error = 0;
1022 int sleeptime;
1023
1024 state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
1025 flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY_1CB) | GL_EXACT;
1026
1027 mutex_lock(&fp->f_fl_mutex);
1028
1029 gl = fl_gh->gh_gl;
1030 if (gl) {
1031 if (fl_gh->gh_state == state)
1032 goto out;
1033 locks_lock_file_wait(file,
1034 &(struct file_lock) {
1035 .fl_type = F_UNLCK,
1036 .fl_flags = FL_FLOCK
1037 });
1038 gfs2_glock_dq(fl_gh);
1039 gfs2_holder_reinit(state, flags, fl_gh);
1040 } else {
1041 error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr,
1042 &gfs2_flock_glops, CREATE, &gl);
1043 if (error)
1044 goto out;
1045 gfs2_holder_init(gl, state, flags, fl_gh);
1046 gfs2_glock_put(gl);
1047 }
1048 for (sleeptime = 1; sleeptime <= 4; sleeptime <<= 1) {
1049 error = gfs2_glock_nq(fl_gh);
1050 if (error != GLR_TRYFAILED)
1051 break;
1052 fl_gh->gh_flags = LM_FLAG_TRY | GL_EXACT;
1053 fl_gh->gh_error = 0;
1054 msleep(sleeptime);
1055 }
1056 if (error) {
1057 gfs2_holder_uninit(fl_gh);
1058 if (error == GLR_TRYFAILED)
1059 error = -EAGAIN;
1060 } else {
1061 error = locks_lock_file_wait(file, fl);
1062 gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error);
1063 }
1064
1065out:
1066 mutex_unlock(&fp->f_fl_mutex);
1067 return error;
1068}
1069
1070static void do_unflock(struct file *file, struct file_lock *fl)
1071{
1072 struct gfs2_file *fp = file->private_data;
1073 struct gfs2_holder *fl_gh = &fp->f_fl_gh;
1074
1075 mutex_lock(&fp->f_fl_mutex);
1076 locks_lock_file_wait(file, fl);
1077 if (gfs2_holder_initialized(fl_gh)) {
1078 gfs2_glock_dq(fl_gh);
1079 gfs2_holder_uninit(fl_gh);
1080 }
1081 mutex_unlock(&fp->f_fl_mutex);
1082}
1083
1084/**
1085 * gfs2_flock - acquire/release a flock lock on a file
1086 * @file: the file pointer
1087 * @cmd: either modify or retrieve lock state, possibly wait
1088 * @fl: type and range of lock
1089 *
1090 * Returns: errno
1091 */
1092
1093static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl)
1094{
1095 if (!(fl->fl_flags & FL_FLOCK))
1096 return -ENOLCK;
1097 if (fl->fl_type & LOCK_MAND)
1098 return -EOPNOTSUPP;
1099
1100 if (fl->fl_type == F_UNLCK) {
1101 do_unflock(file, fl);
1102 return 0;
1103 } else {
1104 return do_flock(file, cmd, fl);
1105 }
1106}
1107
1108const struct file_operations gfs2_file_fops = {
1109 .llseek = gfs2_llseek,
1110 .read_iter = generic_file_read_iter,
1111 .write_iter = gfs2_file_write_iter,
1112 .unlocked_ioctl = gfs2_ioctl,
1113 .mmap = gfs2_mmap,
1114 .open = gfs2_open,
1115 .release = gfs2_release,
1116 .fsync = gfs2_fsync,
1117 .lock = gfs2_lock,
1118 .flock = gfs2_flock,
1119 .splice_read = generic_file_splice_read,
1120 .splice_write = gfs2_file_splice_write,
1121 .setlease = simple_nosetlease,
1122 .fallocate = gfs2_fallocate,
1123};
1124
1125const struct file_operations gfs2_dir_fops = {
1126 .iterate_shared = gfs2_readdir,
1127 .unlocked_ioctl = gfs2_ioctl,
1128 .open = gfs2_open,
1129 .release = gfs2_release,
1130 .fsync = gfs2_fsync,
1131 .lock = gfs2_lock,
1132 .flock = gfs2_flock,
1133 .llseek = default_llseek,
1134};
1135
1136#endif /* CONFIG_GFS2_FS_LOCKING_DLM */
1137
1138const struct file_operations gfs2_file_fops_nolock = {
1139 .llseek = gfs2_llseek,
1140 .read_iter = generic_file_read_iter,
1141 .write_iter = gfs2_file_write_iter,
1142 .unlocked_ioctl = gfs2_ioctl,
1143 .mmap = gfs2_mmap,
1144 .open = gfs2_open,
1145 .release = gfs2_release,
1146 .fsync = gfs2_fsync,
1147 .splice_read = generic_file_splice_read,
1148 .splice_write = gfs2_file_splice_write,
1149 .setlease = generic_setlease,
1150 .fallocate = gfs2_fallocate,
1151};
1152
1153const struct file_operations gfs2_dir_fops_nolock = {
1154 .iterate_shared = gfs2_readdir,
1155 .unlocked_ioctl = gfs2_ioctl,
1156 .open = gfs2_open,
1157 .release = gfs2_release,
1158 .fsync = gfs2_fsync,
1159 .llseek = default_llseek,
1160};
1161
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/falloc.h>
23#include <linux/swap.h>
24#include <linux/crc32.h>
25#include <linux/writeback.h>
26#include <asm/uaccess.h>
27#include <linux/dlm.h>
28#include <linux/dlm_plock.h>
29
30#include "gfs2.h"
31#include "incore.h"
32#include "bmap.h"
33#include "dir.h"
34#include "glock.h"
35#include "glops.h"
36#include "inode.h"
37#include "log.h"
38#include "meta_io.h"
39#include "quota.h"
40#include "rgrp.h"
41#include "trans.h"
42#include "util.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
56static 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
84static 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, 0, &d_gh);
93 error = gfs2_glock_nq(&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 */
118static 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
130static 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
139static 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
148static 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, 0, &gh);
157 error = gfs2_glock_nq(&gh);
158 if (error)
159 return error;
160
161 fsflags = fsflags_cvt(gfs2_to_fsflags, ip->i_diskflags);
162 if (!S_ISDIR(inode->i_mode) && ip->i_diskflags & 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
172void gfs2_set_inode_flags(struct inode *inode)
173{
174 struct gfs2_inode *ip = GFS2_I(inode);
175 unsigned int flags = inode->i_flags;
176
177 flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC|S_NOSEC);
178 if ((ip->i_eattr == 0) && !is_sxid(inode->i_mode))
179 inode->i_flags |= S_NOSEC;
180 if (ip->i_diskflags & GFS2_DIF_IMMUTABLE)
181 flags |= S_IMMUTABLE;
182 if (ip->i_diskflags & GFS2_DIF_APPENDONLY)
183 flags |= S_APPEND;
184 if (ip->i_diskflags & GFS2_DIF_NOATIME)
185 flags |= S_NOATIME;
186 if (ip->i_diskflags & GFS2_DIF_SYNC)
187 flags |= S_SYNC;
188 inode->i_flags = flags;
189}
190
191/* Flags that can be set by user space */
192#define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA| \
193 GFS2_DIF_IMMUTABLE| \
194 GFS2_DIF_APPENDONLY| \
195 GFS2_DIF_NOATIME| \
196 GFS2_DIF_SYNC| \
197 GFS2_DIF_SYSTEM| \
198 GFS2_DIF_INHERIT_JDATA)
199
200/**
201 * gfs2_set_flags - set flags on an inode
202 * @inode: The inode
203 * @flags: The flags to set
204 * @mask: Indicates which flags are valid
205 *
206 */
207static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask)
208{
209 struct inode *inode = filp->f_path.dentry->d_inode;
210 struct gfs2_inode *ip = GFS2_I(inode);
211 struct gfs2_sbd *sdp = GFS2_SB(inode);
212 struct buffer_head *bh;
213 struct gfs2_holder gh;
214 int error;
215 u32 new_flags, flags;
216
217 error = mnt_want_write(filp->f_path.mnt);
218 if (error)
219 return error;
220
221 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
222 if (error)
223 goto out_drop_write;
224
225 error = -EACCES;
226 if (!inode_owner_or_capable(inode))
227 goto out;
228
229 error = 0;
230 flags = ip->i_diskflags;
231 new_flags = (flags & ~mask) | (reqflags & mask);
232 if ((new_flags ^ flags) == 0)
233 goto out;
234
235 error = -EINVAL;
236 if ((new_flags ^ flags) & ~GFS2_FLAGS_USER_SET)
237 goto out;
238
239 error = -EPERM;
240 if (IS_IMMUTABLE(inode) && (new_flags & GFS2_DIF_IMMUTABLE))
241 goto out;
242 if (IS_APPEND(inode) && (new_flags & GFS2_DIF_APPENDONLY))
243 goto out;
244 if (((new_flags ^ flags) & GFS2_DIF_IMMUTABLE) &&
245 !capable(CAP_LINUX_IMMUTABLE))
246 goto out;
247 if (!IS_IMMUTABLE(inode)) {
248 error = gfs2_permission(inode, MAY_WRITE);
249 if (error)
250 goto out;
251 }
252 if ((flags ^ new_flags) & GFS2_DIF_JDATA) {
253 if (flags & GFS2_DIF_JDATA)
254 gfs2_log_flush(sdp, ip->i_gl);
255 error = filemap_fdatawrite(inode->i_mapping);
256 if (error)
257 goto out;
258 error = filemap_fdatawait(inode->i_mapping);
259 if (error)
260 goto out;
261 }
262 error = gfs2_trans_begin(sdp, RES_DINODE, 0);
263 if (error)
264 goto out;
265 error = gfs2_meta_inode_buffer(ip, &bh);
266 if (error)
267 goto out_trans_end;
268 gfs2_trans_add_bh(ip->i_gl, bh, 1);
269 ip->i_diskflags = new_flags;
270 gfs2_dinode_out(ip, bh->b_data);
271 brelse(bh);
272 gfs2_set_inode_flags(inode);
273 gfs2_set_aops(inode);
274out_trans_end:
275 gfs2_trans_end(sdp);
276out:
277 gfs2_glock_dq_uninit(&gh);
278out_drop_write:
279 mnt_drop_write(filp->f_path.mnt);
280 return error;
281}
282
283static int gfs2_set_flags(struct file *filp, u32 __user *ptr)
284{
285 struct inode *inode = filp->f_path.dentry->d_inode;
286 u32 fsflags, gfsflags;
287
288 if (get_user(fsflags, ptr))
289 return -EFAULT;
290
291 gfsflags = fsflags_cvt(fsflags_to_gfs2, fsflags);
292 if (!S_ISDIR(inode->i_mode)) {
293 if (gfsflags & GFS2_DIF_INHERIT_JDATA)
294 gfsflags ^= (GFS2_DIF_JDATA | GFS2_DIF_INHERIT_JDATA);
295 return do_gfs2_set_flags(filp, gfsflags, ~0);
296 }
297 return do_gfs2_set_flags(filp, gfsflags, ~GFS2_DIF_JDATA);
298}
299
300static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
301{
302 switch(cmd) {
303 case FS_IOC_GETFLAGS:
304 return gfs2_get_flags(filp, (u32 __user *)arg);
305 case FS_IOC_SETFLAGS:
306 return gfs2_set_flags(filp, (u32 __user *)arg);
307 }
308 return -ENOTTY;
309}
310
311/**
312 * gfs2_allocate_page_backing - Use bmap to allocate blocks
313 * @page: The (locked) page to allocate backing for
314 *
315 * We try to allocate all the blocks required for the page in
316 * one go. This might fail for various reasons, so we keep
317 * trying until all the blocks to back this page are allocated.
318 * If some of the blocks are already allocated, thats ok too.
319 */
320
321static int gfs2_allocate_page_backing(struct page *page)
322{
323 struct inode *inode = page->mapping->host;
324 struct buffer_head bh;
325 unsigned long size = PAGE_CACHE_SIZE;
326 u64 lblock = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
327
328 do {
329 bh.b_state = 0;
330 bh.b_size = size;
331 gfs2_block_map(inode, lblock, &bh, 1);
332 if (!buffer_mapped(&bh))
333 return -EIO;
334 size -= bh.b_size;
335 lblock += (bh.b_size >> inode->i_blkbits);
336 } while(size > 0);
337 return 0;
338}
339
340/**
341 * gfs2_page_mkwrite - Make a shared, mmap()ed, page writable
342 * @vma: The virtual memory area
343 * @page: The page which is about to become writable
344 *
345 * When the page becomes writable, we need to ensure that we have
346 * blocks allocated on disk to back that page.
347 */
348
349static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
350{
351 struct page *page = vmf->page;
352 struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
353 struct gfs2_inode *ip = GFS2_I(inode);
354 struct gfs2_sbd *sdp = GFS2_SB(inode);
355 unsigned long last_index;
356 u64 pos = page->index << PAGE_CACHE_SHIFT;
357 unsigned int data_blocks, ind_blocks, rblocks;
358 struct gfs2_holder gh;
359 struct gfs2_alloc *al;
360 int ret;
361
362 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
363 ret = gfs2_glock_nq(&gh);
364 if (ret)
365 goto out;
366
367 set_bit(GLF_DIRTY, &ip->i_gl->gl_flags);
368 set_bit(GIF_SW_PAGED, &ip->i_flags);
369
370 if (!gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE))
371 goto out_unlock;
372 ret = -ENOMEM;
373 al = gfs2_alloc_get(ip);
374 if (al == NULL)
375 goto out_unlock;
376
377 ret = gfs2_quota_lock_check(ip);
378 if (ret)
379 goto out_alloc_put;
380 gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks);
381 al->al_requested = data_blocks + ind_blocks;
382 ret = gfs2_inplace_reserve(ip);
383 if (ret)
384 goto out_quota_unlock;
385
386 rblocks = RES_DINODE + ind_blocks;
387 if (gfs2_is_jdata(ip))
388 rblocks += data_blocks ? data_blocks : 1;
389 if (ind_blocks || data_blocks) {
390 rblocks += RES_STATFS + RES_QUOTA;
391 rblocks += gfs2_rg_blocks(al);
392 }
393 ret = gfs2_trans_begin(sdp, rblocks, 0);
394 if (ret)
395 goto out_trans_fail;
396
397 lock_page(page);
398 ret = -EINVAL;
399 last_index = ip->i_inode.i_size >> PAGE_CACHE_SHIFT;
400 if (page->index > last_index)
401 goto out_unlock_page;
402 ret = 0;
403 if (!PageUptodate(page) || page->mapping != ip->i_inode.i_mapping)
404 goto out_unlock_page;
405 if (gfs2_is_stuffed(ip)) {
406 ret = gfs2_unstuff_dinode(ip, page);
407 if (ret)
408 goto out_unlock_page;
409 }
410 ret = gfs2_allocate_page_backing(page);
411
412out_unlock_page:
413 unlock_page(page);
414 gfs2_trans_end(sdp);
415out_trans_fail:
416 gfs2_inplace_release(ip);
417out_quota_unlock:
418 gfs2_quota_unlock(ip);
419out_alloc_put:
420 gfs2_alloc_put(ip);
421out_unlock:
422 gfs2_glock_dq(&gh);
423out:
424 gfs2_holder_uninit(&gh);
425 if (ret == -ENOMEM)
426 ret = VM_FAULT_OOM;
427 else if (ret)
428 ret = VM_FAULT_SIGBUS;
429 return ret;
430}
431
432static const struct vm_operations_struct gfs2_vm_ops = {
433 .fault = filemap_fault,
434 .page_mkwrite = gfs2_page_mkwrite,
435};
436
437/**
438 * gfs2_mmap -
439 * @file: The file to map
440 * @vma: The VMA which described the mapping
441 *
442 * There is no need to get a lock here unless we should be updating
443 * atime. We ignore any locking errors since the only consequence is
444 * a missed atime update (which will just be deferred until later).
445 *
446 * Returns: 0
447 */
448
449static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
450{
451 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
452
453 if (!(file->f_flags & O_NOATIME) &&
454 !IS_NOATIME(&ip->i_inode)) {
455 struct gfs2_holder i_gh;
456 int error;
457
458 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
459 error = gfs2_glock_nq(&i_gh);
460 if (error == 0) {
461 file_accessed(file);
462 gfs2_glock_dq(&i_gh);
463 }
464 gfs2_holder_uninit(&i_gh);
465 if (error)
466 return error;
467 }
468 vma->vm_ops = &gfs2_vm_ops;
469 vma->vm_flags |= VM_CAN_NONLINEAR;
470
471 return 0;
472}
473
474/**
475 * gfs2_open - open a file
476 * @inode: the inode to open
477 * @file: the struct file for this opening
478 *
479 * Returns: errno
480 */
481
482static int gfs2_open(struct inode *inode, struct file *file)
483{
484 struct gfs2_inode *ip = GFS2_I(inode);
485 struct gfs2_holder i_gh;
486 struct gfs2_file *fp;
487 int error;
488
489 fp = kzalloc(sizeof(struct gfs2_file), GFP_KERNEL);
490 if (!fp)
491 return -ENOMEM;
492
493 mutex_init(&fp->f_fl_mutex);
494
495 gfs2_assert_warn(GFS2_SB(inode), !file->private_data);
496 file->private_data = fp;
497
498 if (S_ISREG(ip->i_inode.i_mode)) {
499 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
500 &i_gh);
501 if (error)
502 goto fail;
503
504 if (!(file->f_flags & O_LARGEFILE) &&
505 i_size_read(inode) > MAX_NON_LFS) {
506 error = -EOVERFLOW;
507 goto fail_gunlock;
508 }
509
510 gfs2_glock_dq_uninit(&i_gh);
511 }
512
513 return 0;
514
515fail_gunlock:
516 gfs2_glock_dq_uninit(&i_gh);
517fail:
518 file->private_data = NULL;
519 kfree(fp);
520 return error;
521}
522
523/**
524 * gfs2_close - called to close a struct file
525 * @inode: the inode the struct file belongs to
526 * @file: the struct file being closed
527 *
528 * Returns: errno
529 */
530
531static int gfs2_close(struct inode *inode, struct file *file)
532{
533 struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
534 struct gfs2_file *fp;
535
536 fp = file->private_data;
537 file->private_data = NULL;
538
539 if (gfs2_assert_warn(sdp, fp))
540 return -EIO;
541
542 kfree(fp);
543
544 return 0;
545}
546
547/**
548 * gfs2_fsync - sync the dirty data for a file (across the cluster)
549 * @file: the file that points to the dentry
550 * @start: the start position in the file to sync
551 * @end: the end position in the file to sync
552 * @datasync: set if we can ignore timestamp changes
553 *
554 * The VFS will flush data for us. We only need to worry
555 * about metadata here.
556 *
557 * Returns: errno
558 */
559
560static int gfs2_fsync(struct file *file, loff_t start, loff_t end,
561 int datasync)
562{
563 struct inode *inode = file->f_mapping->host;
564 int sync_state = inode->i_state & (I_DIRTY_SYNC|I_DIRTY_DATASYNC);
565 struct gfs2_inode *ip = GFS2_I(inode);
566 int ret;
567
568 ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
569 if (ret)
570 return ret;
571 mutex_lock(&inode->i_mutex);
572
573 if (datasync)
574 sync_state &= ~I_DIRTY_SYNC;
575
576 if (sync_state) {
577 ret = sync_inode_metadata(inode, 1);
578 if (ret) {
579 mutex_unlock(&inode->i_mutex);
580 return ret;
581 }
582 gfs2_ail_flush(ip->i_gl);
583 }
584
585 mutex_unlock(&inode->i_mutex);
586 return 0;
587}
588
589/**
590 * gfs2_file_aio_write - Perform a write to a file
591 * @iocb: The io context
592 * @iov: The data to write
593 * @nr_segs: Number of @iov segments
594 * @pos: The file position
595 *
596 * We have to do a lock/unlock here to refresh the inode size for
597 * O_APPEND writes, otherwise we can land up writing at the wrong
598 * offset. There is still a race, but provided the app is using its
599 * own file locking, this will make O_APPEND work as expected.
600 *
601 */
602
603static ssize_t gfs2_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
604 unsigned long nr_segs, loff_t pos)
605{
606 struct file *file = iocb->ki_filp;
607
608 if (file->f_flags & O_APPEND) {
609 struct dentry *dentry = file->f_dentry;
610 struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
611 struct gfs2_holder gh;
612 int ret;
613
614 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
615 if (ret)
616 return ret;
617 gfs2_glock_dq_uninit(&gh);
618 }
619
620 return generic_file_aio_write(iocb, iov, nr_segs, pos);
621}
622
623static int empty_write_end(struct page *page, unsigned from,
624 unsigned to, int mode)
625{
626 struct inode *inode = page->mapping->host;
627 struct gfs2_inode *ip = GFS2_I(inode);
628 struct buffer_head *bh;
629 unsigned offset, blksize = 1 << inode->i_blkbits;
630 pgoff_t end_index = i_size_read(inode) >> PAGE_CACHE_SHIFT;
631
632 zero_user(page, from, to-from);
633 mark_page_accessed(page);
634
635 if (page->index < end_index || !(mode & FALLOC_FL_KEEP_SIZE)) {
636 if (!gfs2_is_writeback(ip))
637 gfs2_page_add_databufs(ip, page, from, to);
638
639 block_commit_write(page, from, to);
640 return 0;
641 }
642
643 offset = 0;
644 bh = page_buffers(page);
645 while (offset < to) {
646 if (offset >= from) {
647 set_buffer_uptodate(bh);
648 mark_buffer_dirty(bh);
649 clear_buffer_new(bh);
650 write_dirty_buffer(bh, WRITE);
651 }
652 offset += blksize;
653 bh = bh->b_this_page;
654 }
655
656 offset = 0;
657 bh = page_buffers(page);
658 while (offset < to) {
659 if (offset >= from) {
660 wait_on_buffer(bh);
661 if (!buffer_uptodate(bh))
662 return -EIO;
663 }
664 offset += blksize;
665 bh = bh->b_this_page;
666 }
667 return 0;
668}
669
670static int needs_empty_write(sector_t block, struct inode *inode)
671{
672 int error;
673 struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
674
675 bh_map.b_size = 1 << inode->i_blkbits;
676 error = gfs2_block_map(inode, block, &bh_map, 0);
677 if (unlikely(error))
678 return error;
679 return !buffer_mapped(&bh_map);
680}
681
682static int write_empty_blocks(struct page *page, unsigned from, unsigned to,
683 int mode)
684{
685 struct inode *inode = page->mapping->host;
686 unsigned start, end, next, blksize;
687 sector_t block = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
688 int ret;
689
690 blksize = 1 << inode->i_blkbits;
691 next = end = 0;
692 while (next < from) {
693 next += blksize;
694 block++;
695 }
696 start = next;
697 do {
698 next += blksize;
699 ret = needs_empty_write(block, inode);
700 if (unlikely(ret < 0))
701 return ret;
702 if (ret == 0) {
703 if (end) {
704 ret = __block_write_begin(page, start, end - start,
705 gfs2_block_map);
706 if (unlikely(ret))
707 return ret;
708 ret = empty_write_end(page, start, end, mode);
709 if (unlikely(ret))
710 return ret;
711 end = 0;
712 }
713 start = next;
714 }
715 else
716 end = next;
717 block++;
718 } while (next < to);
719
720 if (end) {
721 ret = __block_write_begin(page, start, end - start, gfs2_block_map);
722 if (unlikely(ret))
723 return ret;
724 ret = empty_write_end(page, start, end, mode);
725 if (unlikely(ret))
726 return ret;
727 }
728
729 return 0;
730}
731
732static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len,
733 int mode)
734{
735 struct gfs2_inode *ip = GFS2_I(inode);
736 struct buffer_head *dibh;
737 int error;
738 u64 start = offset >> PAGE_CACHE_SHIFT;
739 unsigned int start_offset = offset & ~PAGE_CACHE_MASK;
740 u64 end = (offset + len - 1) >> PAGE_CACHE_SHIFT;
741 pgoff_t curr;
742 struct page *page;
743 unsigned int end_offset = (offset + len) & ~PAGE_CACHE_MASK;
744 unsigned int from, to;
745
746 if (!end_offset)
747 end_offset = PAGE_CACHE_SIZE;
748
749 error = gfs2_meta_inode_buffer(ip, &dibh);
750 if (unlikely(error))
751 goto out;
752
753 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
754
755 if (gfs2_is_stuffed(ip)) {
756 error = gfs2_unstuff_dinode(ip, NULL);
757 if (unlikely(error))
758 goto out;
759 }
760
761 curr = start;
762 offset = start << PAGE_CACHE_SHIFT;
763 from = start_offset;
764 to = PAGE_CACHE_SIZE;
765 while (curr <= end) {
766 page = grab_cache_page_write_begin(inode->i_mapping, curr,
767 AOP_FLAG_NOFS);
768 if (unlikely(!page)) {
769 error = -ENOMEM;
770 goto out;
771 }
772
773 if (curr == end)
774 to = end_offset;
775 error = write_empty_blocks(page, from, to, mode);
776 if (!error && offset + to > inode->i_size &&
777 !(mode & FALLOC_FL_KEEP_SIZE)) {
778 i_size_write(inode, offset + to);
779 }
780 unlock_page(page);
781 page_cache_release(page);
782 if (error)
783 goto out;
784 curr++;
785 offset += PAGE_CACHE_SIZE;
786 from = 0;
787 }
788
789 gfs2_dinode_out(ip, dibh->b_data);
790 mark_inode_dirty(inode);
791
792 brelse(dibh);
793
794out:
795 return error;
796}
797
798static void calc_max_reserv(struct gfs2_inode *ip, loff_t max, loff_t *len,
799 unsigned int *data_blocks, unsigned int *ind_blocks)
800{
801 const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
802 unsigned int max_blocks = ip->i_alloc->al_rgd->rd_free_clone;
803 unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1);
804
805 for (tmp = max_data; tmp > sdp->sd_diptrs;) {
806 tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
807 max_data -= tmp;
808 }
809 /* This calculation isn't the exact reverse of gfs2_write_calc_reserve,
810 so it might end up with fewer data blocks */
811 if (max_data <= *data_blocks)
812 return;
813 *data_blocks = max_data;
814 *ind_blocks = max_blocks - max_data;
815 *len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift;
816 if (*len > max) {
817 *len = max;
818 gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks);
819 }
820}
821
822static long gfs2_fallocate(struct file *file, int mode, loff_t offset,
823 loff_t len)
824{
825 struct inode *inode = file->f_path.dentry->d_inode;
826 struct gfs2_sbd *sdp = GFS2_SB(inode);
827 struct gfs2_inode *ip = GFS2_I(inode);
828 unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
829 loff_t bytes, max_bytes;
830 struct gfs2_alloc *al;
831 int error;
832 loff_t bsize_mask = ~((loff_t)sdp->sd_sb.sb_bsize - 1);
833 loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift;
834 next = (next + 1) << sdp->sd_sb.sb_bsize_shift;
835
836 /* We only support the FALLOC_FL_KEEP_SIZE mode */
837 if (mode & ~FALLOC_FL_KEEP_SIZE)
838 return -EOPNOTSUPP;
839
840 offset &= bsize_mask;
841
842 len = next - offset;
843 bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2;
844 if (!bytes)
845 bytes = UINT_MAX;
846 bytes &= bsize_mask;
847 if (bytes == 0)
848 bytes = sdp->sd_sb.sb_bsize;
849
850 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ip->i_gh);
851 error = gfs2_glock_nq(&ip->i_gh);
852 if (unlikely(error))
853 goto out_uninit;
854
855 if (!gfs2_write_alloc_required(ip, offset, len))
856 goto out_unlock;
857
858 while (len > 0) {
859 if (len < bytes)
860 bytes = len;
861 al = gfs2_alloc_get(ip);
862 if (!al) {
863 error = -ENOMEM;
864 goto out_unlock;
865 }
866
867 error = gfs2_quota_lock_check(ip);
868 if (error)
869 goto out_alloc_put;
870
871retry:
872 gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks);
873
874 al->al_requested = data_blocks + ind_blocks;
875 error = gfs2_inplace_reserve(ip);
876 if (error) {
877 if (error == -ENOSPC && bytes > sdp->sd_sb.sb_bsize) {
878 bytes >>= 1;
879 bytes &= bsize_mask;
880 if (bytes == 0)
881 bytes = sdp->sd_sb.sb_bsize;
882 goto retry;
883 }
884 goto out_qunlock;
885 }
886 max_bytes = bytes;
887 calc_max_reserv(ip, len, &max_bytes, &data_blocks, &ind_blocks);
888 al->al_requested = data_blocks + ind_blocks;
889
890 rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA +
891 RES_RG_HDR + gfs2_rg_blocks(al);
892 if (gfs2_is_jdata(ip))
893 rblocks += data_blocks ? data_blocks : 1;
894
895 error = gfs2_trans_begin(sdp, rblocks,
896 PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize);
897 if (error)
898 goto out_trans_fail;
899
900 error = fallocate_chunk(inode, offset, max_bytes, mode);
901 gfs2_trans_end(sdp);
902
903 if (error)
904 goto out_trans_fail;
905
906 len -= max_bytes;
907 offset += max_bytes;
908 gfs2_inplace_release(ip);
909 gfs2_quota_unlock(ip);
910 gfs2_alloc_put(ip);
911 }
912 goto out_unlock;
913
914out_trans_fail:
915 gfs2_inplace_release(ip);
916out_qunlock:
917 gfs2_quota_unlock(ip);
918out_alloc_put:
919 gfs2_alloc_put(ip);
920out_unlock:
921 gfs2_glock_dq(&ip->i_gh);
922out_uninit:
923 gfs2_holder_uninit(&ip->i_gh);
924 return error;
925}
926
927#ifdef CONFIG_GFS2_FS_LOCKING_DLM
928
929/**
930 * gfs2_setlease - acquire/release a file lease
931 * @file: the file pointer
932 * @arg: lease type
933 * @fl: file lock
934 *
935 * We don't currently have a way to enforce a lease across the whole
936 * cluster; until we do, disable leases (by just returning -EINVAL),
937 * unless the administrator has requested purely local locking.
938 *
939 * Locking: called under lock_flocks
940 *
941 * Returns: errno
942 */
943
944static int gfs2_setlease(struct file *file, long arg, struct file_lock **fl)
945{
946 return -EINVAL;
947}
948
949/**
950 * gfs2_lock - acquire/release a posix lock on a file
951 * @file: the file pointer
952 * @cmd: either modify or retrieve lock state, possibly wait
953 * @fl: type and range of lock
954 *
955 * Returns: errno
956 */
957
958static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
959{
960 struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
961 struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
962 struct lm_lockstruct *ls = &sdp->sd_lockstruct;
963
964 if (!(fl->fl_flags & FL_POSIX))
965 return -ENOLCK;
966 if (__mandatory_lock(&ip->i_inode) && fl->fl_type != F_UNLCK)
967 return -ENOLCK;
968
969 if (cmd == F_CANCELLK) {
970 /* Hack: */
971 cmd = F_SETLK;
972 fl->fl_type = F_UNLCK;
973 }
974 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
975 return -EIO;
976 if (IS_GETLK(cmd))
977 return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl);
978 else if (fl->fl_type == F_UNLCK)
979 return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl);
980 else
981 return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl);
982}
983
984static int do_flock(struct file *file, int cmd, struct file_lock *fl)
985{
986 struct gfs2_file *fp = file->private_data;
987 struct gfs2_holder *fl_gh = &fp->f_fl_gh;
988 struct gfs2_inode *ip = GFS2_I(file->f_path.dentry->d_inode);
989 struct gfs2_glock *gl;
990 unsigned int state;
991 int flags;
992 int error = 0;
993
994 state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
995 flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE;
996
997 mutex_lock(&fp->f_fl_mutex);
998
999 gl = fl_gh->gh_gl;
1000 if (gl) {
1001 if (fl_gh->gh_state == state)
1002 goto out;
1003 flock_lock_file_wait(file,
1004 &(struct file_lock){.fl_type = F_UNLCK});
1005 gfs2_glock_dq_wait(fl_gh);
1006 gfs2_holder_reinit(state, flags, fl_gh);
1007 } else {
1008 error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr,
1009 &gfs2_flock_glops, CREATE, &gl);
1010 if (error)
1011 goto out;
1012 gfs2_holder_init(gl, state, flags, fl_gh);
1013 gfs2_glock_put(gl);
1014 }
1015 error = gfs2_glock_nq(fl_gh);
1016 if (error) {
1017 gfs2_holder_uninit(fl_gh);
1018 if (error == GLR_TRYFAILED)
1019 error = -EAGAIN;
1020 } else {
1021 error = flock_lock_file_wait(file, fl);
1022 gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error);
1023 }
1024
1025out:
1026 mutex_unlock(&fp->f_fl_mutex);
1027 return error;
1028}
1029
1030static void do_unflock(struct file *file, struct file_lock *fl)
1031{
1032 struct gfs2_file *fp = file->private_data;
1033 struct gfs2_holder *fl_gh = &fp->f_fl_gh;
1034
1035 mutex_lock(&fp->f_fl_mutex);
1036 flock_lock_file_wait(file, fl);
1037 if (fl_gh->gh_gl) {
1038 gfs2_glock_dq_wait(fl_gh);
1039 gfs2_holder_uninit(fl_gh);
1040 }
1041 mutex_unlock(&fp->f_fl_mutex);
1042}
1043
1044/**
1045 * gfs2_flock - acquire/release a flock lock on a file
1046 * @file: the file pointer
1047 * @cmd: either modify or retrieve lock state, possibly wait
1048 * @fl: type and range of lock
1049 *
1050 * Returns: errno
1051 */
1052
1053static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl)
1054{
1055 if (!(fl->fl_flags & FL_FLOCK))
1056 return -ENOLCK;
1057 if (fl->fl_type & LOCK_MAND)
1058 return -EOPNOTSUPP;
1059
1060 if (fl->fl_type == F_UNLCK) {
1061 do_unflock(file, fl);
1062 return 0;
1063 } else {
1064 return do_flock(file, cmd, fl);
1065 }
1066}
1067
1068const struct file_operations gfs2_file_fops = {
1069 .llseek = gfs2_llseek,
1070 .read = do_sync_read,
1071 .aio_read = generic_file_aio_read,
1072 .write = do_sync_write,
1073 .aio_write = gfs2_file_aio_write,
1074 .unlocked_ioctl = gfs2_ioctl,
1075 .mmap = gfs2_mmap,
1076 .open = gfs2_open,
1077 .release = gfs2_close,
1078 .fsync = gfs2_fsync,
1079 .lock = gfs2_lock,
1080 .flock = gfs2_flock,
1081 .splice_read = generic_file_splice_read,
1082 .splice_write = generic_file_splice_write,
1083 .setlease = gfs2_setlease,
1084 .fallocate = gfs2_fallocate,
1085};
1086
1087const struct file_operations gfs2_dir_fops = {
1088 .readdir = gfs2_readdir,
1089 .unlocked_ioctl = gfs2_ioctl,
1090 .open = gfs2_open,
1091 .release = gfs2_close,
1092 .fsync = gfs2_fsync,
1093 .lock = gfs2_lock,
1094 .flock = gfs2_flock,
1095 .llseek = default_llseek,
1096};
1097
1098#endif /* CONFIG_GFS2_FS_LOCKING_DLM */
1099
1100const struct file_operations gfs2_file_fops_nolock = {
1101 .llseek = gfs2_llseek,
1102 .read = do_sync_read,
1103 .aio_read = generic_file_aio_read,
1104 .write = do_sync_write,
1105 .aio_write = gfs2_file_aio_write,
1106 .unlocked_ioctl = gfs2_ioctl,
1107 .mmap = gfs2_mmap,
1108 .open = gfs2_open,
1109 .release = gfs2_close,
1110 .fsync = gfs2_fsync,
1111 .splice_read = generic_file_splice_read,
1112 .splice_write = generic_file_splice_write,
1113 .setlease = generic_setlease,
1114 .fallocate = gfs2_fallocate,
1115};
1116
1117const struct file_operations gfs2_dir_fops_nolock = {
1118 .readdir = gfs2_readdir,
1119 .unlocked_ioctl = gfs2_ioctl,
1120 .open = gfs2_open,
1121 .release = gfs2_close,
1122 .fsync = gfs2_fsync,
1123 .llseek = default_llseek,
1124};
1125