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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/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 | |
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, 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 | */ |
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, 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 | |
172 | void 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); |
178 | if (ip->i_diskflags & GFS2_DIF_IMMUTABLE) |
179 | flags |= S_IMMUTABLE; |
180 | if (ip->i_diskflags & GFS2_DIF_APPENDONLY) |
181 | flags |= S_APPEND; |
182 | if (ip->i_diskflags & GFS2_DIF_NOATIME) |
183 | flags |= S_NOATIME; |
184 | if (ip->i_diskflags & GFS2_DIF_SYNC) |
185 | flags |= S_SYNC; |
186 | inode->i_flags = flags; |
187 | } |
188 | |
189 | /* Flags that can be set by user space */ |
190 | #define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA| \ |
191 | GFS2_DIF_IMMUTABLE| \ |
192 | GFS2_DIF_APPENDONLY| \ |
193 | GFS2_DIF_NOATIME| \ |
194 | GFS2_DIF_SYNC| \ |
195 | GFS2_DIF_SYSTEM| \ |
196 | GFS2_DIF_INHERIT_JDATA) |
197 | |
198 | /** |
199 | * gfs2_set_flags - set flags on an inode |
200 | * @inode: The inode |
201 | * @flags: The flags to set |
202 | * @mask: Indicates which flags are valid |
203 | * |
204 | */ |
205 | static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask) |
206 | { |
207 | struct inode *inode = filp->f_path.dentry->d_inode; |
208 | struct gfs2_inode *ip = GFS2_I(inode); |
209 | struct gfs2_sbd *sdp = GFS2_SB(inode); |
210 | struct buffer_head *bh; |
211 | struct gfs2_holder gh; |
212 | int error; |
213 | u32 new_flags, flags; |
214 | |
215 | error = mnt_want_write(filp->f_path.mnt); |
216 | if (error) |
217 | return error; |
218 | |
219 | error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); |
220 | if (error) |
221 | goto out_drop_write; |
222 | |
223 | error = -EACCES; |
224 | if (!inode_owner_or_capable(inode)) |
225 | goto out; |
226 | |
227 | error = 0; |
228 | flags = ip->i_diskflags; |
229 | new_flags = (flags & ~mask) | (reqflags & mask); |
230 | if ((new_flags ^ flags) == 0) |
231 | goto out; |
232 | |
233 | error = -EINVAL; |
234 | if ((new_flags ^ flags) & ~GFS2_FLAGS_USER_SET) |
235 | goto out; |
236 | |
237 | error = -EPERM; |
238 | if (IS_IMMUTABLE(inode) && (new_flags & GFS2_DIF_IMMUTABLE)) |
239 | goto out; |
240 | if (IS_APPEND(inode) && (new_flags & GFS2_DIF_APPENDONLY)) |
241 | goto out; |
242 | if (((new_flags ^ flags) & GFS2_DIF_IMMUTABLE) && |
243 | !capable(CAP_LINUX_IMMUTABLE)) |
244 | goto out; |
245 | if (!IS_IMMUTABLE(inode)) { |
246 | error = gfs2_permission(inode, MAY_WRITE, 0); |
247 | if (error) |
248 | goto out; |
249 | } |
250 | if ((flags ^ new_flags) & GFS2_DIF_JDATA) { |
251 | if (flags & GFS2_DIF_JDATA) |
252 | gfs2_log_flush(sdp, ip->i_gl); |
253 | error = filemap_fdatawrite(inode->i_mapping); |
254 | if (error) |
255 | goto out; |
256 | error = filemap_fdatawait(inode->i_mapping); |
257 | if (error) |
258 | goto out; |
259 | } |
260 | error = gfs2_trans_begin(sdp, RES_DINODE, 0); |
261 | if (error) |
262 | goto out; |
263 | error = gfs2_meta_inode_buffer(ip, &bh); |
264 | if (error) |
265 | goto out_trans_end; |
266 | gfs2_trans_add_bh(ip->i_gl, bh, 1); |
267 | ip->i_diskflags = new_flags; |
268 | gfs2_dinode_out(ip, bh->b_data); |
269 | brelse(bh); |
270 | gfs2_set_inode_flags(inode); |
271 | gfs2_set_aops(inode); |
272 | out_trans_end: |
273 | gfs2_trans_end(sdp); |
274 | out: |
275 | gfs2_glock_dq_uninit(&gh); |
276 | out_drop_write: |
277 | mnt_drop_write(filp->f_path.mnt); |
278 | return error; |
279 | } |
280 | |
281 | static int gfs2_set_flags(struct file *filp, u32 __user *ptr) |
282 | { |
283 | struct inode *inode = filp->f_path.dentry->d_inode; |
284 | u32 fsflags, gfsflags; |
285 | |
286 | if (get_user(fsflags, ptr)) |
287 | return -EFAULT; |
288 | |
289 | gfsflags = fsflags_cvt(fsflags_to_gfs2, fsflags); |
290 | if (!S_ISDIR(inode->i_mode)) { |
291 | if (gfsflags & GFS2_DIF_INHERIT_JDATA) |
292 | gfsflags ^= (GFS2_DIF_JDATA | GFS2_DIF_INHERIT_JDATA); |
293 | return do_gfs2_set_flags(filp, gfsflags, ~0); |
294 | } |
295 | return do_gfs2_set_flags(filp, gfsflags, ~GFS2_DIF_JDATA); |
296 | } |
297 | |
298 | static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) |
299 | { |
300 | switch(cmd) { |
301 | case FS_IOC_GETFLAGS: |
302 | return gfs2_get_flags(filp, (u32 __user *)arg); |
303 | case FS_IOC_SETFLAGS: |
304 | return gfs2_set_flags(filp, (u32 __user *)arg); |
305 | } |
306 | return -ENOTTY; |
307 | } |
308 | |
309 | /** |
310 | * gfs2_allocate_page_backing - Use bmap to allocate blocks |
311 | * @page: The (locked) page to allocate backing for |
312 | * |
313 | * We try to allocate all the blocks required for the page in |
314 | * one go. This might fail for various reasons, so we keep |
315 | * trying until all the blocks to back this page are allocated. |
316 | * If some of the blocks are already allocated, thats ok too. |
317 | */ |
318 | |
319 | static int gfs2_allocate_page_backing(struct page *page) |
320 | { |
321 | struct inode *inode = page->mapping->host; |
322 | struct buffer_head bh; |
323 | unsigned long size = PAGE_CACHE_SIZE; |
324 | u64 lblock = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits); |
325 | |
326 | do { |
327 | bh.b_state = 0; |
328 | bh.b_size = size; |
329 | gfs2_block_map(inode, lblock, &bh, 1); |
330 | if (!buffer_mapped(&bh)) |
331 | return -EIO; |
332 | size -= bh.b_size; |
333 | lblock += (bh.b_size >> inode->i_blkbits); |
334 | } while(size > 0); |
335 | return 0; |
336 | } |
337 | |
338 | /** |
339 | * gfs2_page_mkwrite - Make a shared, mmap()ed, page writable |
340 | * @vma: The virtual memory area |
341 | * @page: The page which is about to become writable |
342 | * |
343 | * When the page becomes writable, we need to ensure that we have |
344 | * blocks allocated on disk to back that page. |
345 | */ |
346 | |
347 | static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) |
348 | { |
349 | struct page *page = vmf->page; |
350 | struct inode *inode = vma->vm_file->f_path.dentry->d_inode; |
351 | struct gfs2_inode *ip = GFS2_I(inode); |
352 | struct gfs2_sbd *sdp = GFS2_SB(inode); |
353 | unsigned long last_index; |
354 | u64 pos = page->index << PAGE_CACHE_SHIFT; |
355 | unsigned int data_blocks, ind_blocks, rblocks; |
356 | struct gfs2_holder gh; |
357 | struct gfs2_alloc *al; |
358 | int ret; |
359 | |
360 | gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); |
361 | ret = gfs2_glock_nq(&gh); |
362 | if (ret) |
363 | goto out; |
364 | |
365 | set_bit(GLF_DIRTY, &ip->i_gl->gl_flags); |
366 | set_bit(GIF_SW_PAGED, &ip->i_flags); |
367 | |
368 | if (!gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE)) |
369 | goto out_unlock; |
370 | ret = -ENOMEM; |
371 | al = gfs2_alloc_get(ip); |
372 | if (al == NULL) |
373 | goto out_unlock; |
374 | |
375 | ret = gfs2_quota_lock_check(ip); |
376 | if (ret) |
377 | goto out_alloc_put; |
378 | gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks); |
379 | al->al_requested = data_blocks + ind_blocks; |
380 | ret = gfs2_inplace_reserve(ip); |
381 | if (ret) |
382 | goto out_quota_unlock; |
383 | |
384 | rblocks = RES_DINODE + ind_blocks; |
385 | if (gfs2_is_jdata(ip)) |
386 | rblocks += data_blocks ? data_blocks : 1; |
387 | if (ind_blocks || data_blocks) { |
388 | rblocks += RES_STATFS + RES_QUOTA; |
389 | rblocks += gfs2_rg_blocks(al); |
390 | } |
391 | ret = gfs2_trans_begin(sdp, rblocks, 0); |
392 | if (ret) |
393 | goto out_trans_fail; |
394 | |
395 | lock_page(page); |
396 | ret = -EINVAL; |
397 | last_index = ip->i_inode.i_size >> PAGE_CACHE_SHIFT; |
398 | if (page->index > last_index) |
399 | goto out_unlock_page; |
400 | ret = 0; |
401 | if (!PageUptodate(page) || page->mapping != ip->i_inode.i_mapping) |
402 | goto out_unlock_page; |
403 | if (gfs2_is_stuffed(ip)) { |
404 | ret = gfs2_unstuff_dinode(ip, page); |
405 | if (ret) |
406 | goto out_unlock_page; |
407 | } |
408 | ret = gfs2_allocate_page_backing(page); |
409 | |
410 | out_unlock_page: |
411 | unlock_page(page); |
412 | gfs2_trans_end(sdp); |
413 | out_trans_fail: |
414 | gfs2_inplace_release(ip); |
415 | out_quota_unlock: |
416 | gfs2_quota_unlock(ip); |
417 | out_alloc_put: |
418 | gfs2_alloc_put(ip); |
419 | out_unlock: |
420 | gfs2_glock_dq(&gh); |
421 | out: |
422 | gfs2_holder_uninit(&gh); |
423 | if (ret == -ENOMEM) |
424 | ret = VM_FAULT_OOM; |
425 | else if (ret) |
426 | ret = VM_FAULT_SIGBUS; |
427 | return ret; |
428 | } |
429 | |
430 | static const struct vm_operations_struct gfs2_vm_ops = { |
431 | .fault = filemap_fault, |
432 | .page_mkwrite = gfs2_page_mkwrite, |
433 | }; |
434 | |
435 | /** |
436 | * gfs2_mmap - |
437 | * @file: The file to map |
438 | * @vma: The VMA which described the mapping |
439 | * |
440 | * There is no need to get a lock here unless we should be updating |
441 | * atime. We ignore any locking errors since the only consequence is |
442 | * a missed atime update (which will just be deferred until later). |
443 | * |
444 | * Returns: 0 |
445 | */ |
446 | |
447 | static int gfs2_mmap(struct file *file, struct vm_area_struct *vma) |
448 | { |
449 | struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); |
450 | |
451 | if (!(file->f_flags & O_NOATIME) && |
452 | !IS_NOATIME(&ip->i_inode)) { |
453 | struct gfs2_holder i_gh; |
454 | int error; |
455 | |
456 | gfs2_holder_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh); |
457 | error = gfs2_glock_nq(&i_gh); |
458 | if (error == 0) { |
459 | file_accessed(file); |
460 | gfs2_glock_dq(&i_gh); |
461 | } |
462 | gfs2_holder_uninit(&i_gh); |
463 | if (error) |
464 | return error; |
465 | } |
466 | vma->vm_ops = &gfs2_vm_ops; |
467 | vma->vm_flags |= VM_CAN_NONLINEAR; |
468 | |
469 | return 0; |
470 | } |
471 | |
472 | /** |
473 | * gfs2_open - open a file |
474 | * @inode: the inode to open |
475 | * @file: the struct file for this opening |
476 | * |
477 | * Returns: errno |
478 | */ |
479 | |
480 | static int gfs2_open(struct inode *inode, struct file *file) |
481 | { |
482 | struct gfs2_inode *ip = GFS2_I(inode); |
483 | struct gfs2_holder i_gh; |
484 | struct gfs2_file *fp; |
485 | int error; |
486 | |
487 | fp = kzalloc(sizeof(struct gfs2_file), GFP_KERNEL); |
488 | if (!fp) |
489 | return -ENOMEM; |
490 | |
491 | mutex_init(&fp->f_fl_mutex); |
492 | |
493 | gfs2_assert_warn(GFS2_SB(inode), !file->private_data); |
494 | file->private_data = fp; |
495 | |
496 | if (S_ISREG(ip->i_inode.i_mode)) { |
497 | error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, |
498 | &i_gh); |
499 | if (error) |
500 | goto fail; |
501 | |
502 | if (!(file->f_flags & O_LARGEFILE) && |
503 | i_size_read(inode) > MAX_NON_LFS) { |
504 | error = -EOVERFLOW; |
505 | goto fail_gunlock; |
506 | } |
507 | |
508 | gfs2_glock_dq_uninit(&i_gh); |
509 | } |
510 | |
511 | return 0; |
512 | |
513 | fail_gunlock: |
514 | gfs2_glock_dq_uninit(&i_gh); |
515 | fail: |
516 | file->private_data = NULL; |
517 | kfree(fp); |
518 | return error; |
519 | } |
520 | |
521 | /** |
522 | * gfs2_close - called to close a struct file |
523 | * @inode: the inode the struct file belongs to |
524 | * @file: the struct file being closed |
525 | * |
526 | * Returns: errno |
527 | */ |
528 | |
529 | static int gfs2_close(struct inode *inode, struct file *file) |
530 | { |
531 | struct gfs2_sbd *sdp = inode->i_sb->s_fs_info; |
532 | struct gfs2_file *fp; |
533 | |
534 | fp = file->private_data; |
535 | file->private_data = NULL; |
536 | |
537 | if (gfs2_assert_warn(sdp, fp)) |
538 | return -EIO; |
539 | |
540 | kfree(fp); |
541 | |
542 | return 0; |
543 | } |
544 | |
545 | /** |
546 | * gfs2_fsync - sync the dirty data for a file (across the cluster) |
547 | * @file: the file that points to the dentry (we ignore this) |
548 | * @datasync: set if we can ignore timestamp changes |
549 | * |
550 | * The VFS will flush data for us. We only need to worry |
551 | * about metadata here. |
552 | * |
553 | * Returns: errno |
554 | */ |
555 | |
556 | static int gfs2_fsync(struct file *file, int datasync) |
557 | { |
558 | struct inode *inode = file->f_mapping->host; |
559 | int sync_state = inode->i_state & (I_DIRTY_SYNC|I_DIRTY_DATASYNC); |
560 | struct gfs2_inode *ip = GFS2_I(inode); |
561 | int ret; |
562 | |
563 | if (datasync) |
564 | sync_state &= ~I_DIRTY_SYNC; |
565 | |
566 | if (sync_state) { |
567 | ret = sync_inode_metadata(inode, 1); |
568 | if (ret) |
569 | return ret; |
570 | gfs2_ail_flush(ip->i_gl); |
571 | } |
572 | |
573 | return 0; |
574 | } |
575 | |
576 | /** |
577 | * gfs2_file_aio_write - Perform a write to a file |
578 | * @iocb: The io context |
579 | * @iov: The data to write |
580 | * @nr_segs: Number of @iov segments |
581 | * @pos: The file position |
582 | * |
583 | * We have to do a lock/unlock here to refresh the inode size for |
584 | * O_APPEND writes, otherwise we can land up writing at the wrong |
585 | * offset. There is still a race, but provided the app is using its |
586 | * own file locking, this will make O_APPEND work as expected. |
587 | * |
588 | */ |
589 | |
590 | static ssize_t gfs2_file_aio_write(struct kiocb *iocb, const struct iovec *iov, |
591 | unsigned long nr_segs, loff_t pos) |
592 | { |
593 | struct file *file = iocb->ki_filp; |
594 | |
595 | if (file->f_flags & O_APPEND) { |
596 | struct dentry *dentry = file->f_dentry; |
597 | struct gfs2_inode *ip = GFS2_I(dentry->d_inode); |
598 | struct gfs2_holder gh; |
599 | int ret; |
600 | |
601 | ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh); |
602 | if (ret) |
603 | return ret; |
604 | gfs2_glock_dq_uninit(&gh); |
605 | } |
606 | |
607 | return generic_file_aio_write(iocb, iov, nr_segs, pos); |
608 | } |
609 | |
610 | static int empty_write_end(struct page *page, unsigned from, |
611 | unsigned to, int mode) |
612 | { |
613 | struct inode *inode = page->mapping->host; |
614 | struct gfs2_inode *ip = GFS2_I(inode); |
615 | struct buffer_head *bh; |
616 | unsigned offset, blksize = 1 << inode->i_blkbits; |
617 | pgoff_t end_index = i_size_read(inode) >> PAGE_CACHE_SHIFT; |
618 | |
619 | zero_user(page, from, to-from); |
620 | mark_page_accessed(page); |
621 | |
622 | if (page->index < end_index || !(mode & FALLOC_FL_KEEP_SIZE)) { |
623 | if (!gfs2_is_writeback(ip)) |
624 | gfs2_page_add_databufs(ip, page, from, to); |
625 | |
626 | block_commit_write(page, from, to); |
627 | return 0; |
628 | } |
629 | |
630 | offset = 0; |
631 | bh = page_buffers(page); |
632 | while (offset < to) { |
633 | if (offset >= from) { |
634 | set_buffer_uptodate(bh); |
635 | mark_buffer_dirty(bh); |
636 | clear_buffer_new(bh); |
637 | write_dirty_buffer(bh, WRITE); |
638 | } |
639 | offset += blksize; |
640 | bh = bh->b_this_page; |
641 | } |
642 | |
643 | offset = 0; |
644 | bh = page_buffers(page); |
645 | while (offset < to) { |
646 | if (offset >= from) { |
647 | wait_on_buffer(bh); |
648 | if (!buffer_uptodate(bh)) |
649 | return -EIO; |
650 | } |
651 | offset += blksize; |
652 | bh = bh->b_this_page; |
653 | } |
654 | return 0; |
655 | } |
656 | |
657 | static int needs_empty_write(sector_t block, struct inode *inode) |
658 | { |
659 | int error; |
660 | struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 }; |
661 | |
662 | bh_map.b_size = 1 << inode->i_blkbits; |
663 | error = gfs2_block_map(inode, block, &bh_map, 0); |
664 | if (unlikely(error)) |
665 | return error; |
666 | return !buffer_mapped(&bh_map); |
667 | } |
668 | |
669 | static int write_empty_blocks(struct page *page, unsigned from, unsigned to, |
670 | int mode) |
671 | { |
672 | struct inode *inode = page->mapping->host; |
673 | unsigned start, end, next, blksize; |
674 | sector_t block = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits); |
675 | int ret; |
676 | |
677 | blksize = 1 << inode->i_blkbits; |
678 | next = end = 0; |
679 | while (next < from) { |
680 | next += blksize; |
681 | block++; |
682 | } |
683 | start = next; |
684 | do { |
685 | next += blksize; |
686 | ret = needs_empty_write(block, inode); |
687 | if (unlikely(ret < 0)) |
688 | return ret; |
689 | if (ret == 0) { |
690 | if (end) { |
691 | ret = __block_write_begin(page, start, end - start, |
692 | gfs2_block_map); |
693 | if (unlikely(ret)) |
694 | return ret; |
695 | ret = empty_write_end(page, start, end, mode); |
696 | if (unlikely(ret)) |
697 | return ret; |
698 | end = 0; |
699 | } |
700 | start = next; |
701 | } |
702 | else |
703 | end = next; |
704 | block++; |
705 | } while (next < to); |
706 | |
707 | if (end) { |
708 | ret = __block_write_begin(page, start, end - start, gfs2_block_map); |
709 | if (unlikely(ret)) |
710 | return ret; |
711 | ret = empty_write_end(page, start, end, mode); |
712 | if (unlikely(ret)) |
713 | return ret; |
714 | } |
715 | |
716 | return 0; |
717 | } |
718 | |
719 | static 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 | u64 start = offset >> PAGE_CACHE_SHIFT; |
726 | unsigned int start_offset = offset & ~PAGE_CACHE_MASK; |
727 | u64 end = (offset + len - 1) >> PAGE_CACHE_SHIFT; |
728 | pgoff_t curr; |
729 | struct page *page; |
730 | unsigned int end_offset = (offset + len) & ~PAGE_CACHE_MASK; |
731 | unsigned int from, to; |
732 | |
733 | if (!end_offset) |
734 | end_offset = PAGE_CACHE_SIZE; |
735 | |
736 | error = gfs2_meta_inode_buffer(ip, &dibh); |
737 | if (unlikely(error)) |
738 | goto out; |
739 | |
740 | gfs2_trans_add_bh(ip->i_gl, dibh, 1); |
741 | |
742 | if (gfs2_is_stuffed(ip)) { |
743 | error = gfs2_unstuff_dinode(ip, NULL); |
744 | if (unlikely(error)) |
745 | goto out; |
746 | } |
747 | |
748 | curr = start; |
749 | offset = start << PAGE_CACHE_SHIFT; |
750 | from = start_offset; |
751 | to = PAGE_CACHE_SIZE; |
752 | while (curr <= end) { |
753 | page = grab_cache_page_write_begin(inode->i_mapping, curr, |
754 | AOP_FLAG_NOFS); |
755 | if (unlikely(!page)) { |
756 | error = -ENOMEM; |
757 | goto out; |
758 | } |
759 | |
760 | if (curr == end) |
761 | to = end_offset; |
762 | error = write_empty_blocks(page, from, to, mode); |
763 | if (!error && offset + to > inode->i_size && |
764 | !(mode & FALLOC_FL_KEEP_SIZE)) { |
765 | i_size_write(inode, offset + to); |
766 | } |
767 | unlock_page(page); |
768 | page_cache_release(page); |
769 | if (error) |
770 | goto out; |
771 | curr++; |
772 | offset += PAGE_CACHE_SIZE; |
773 | from = 0; |
774 | } |
775 | |
776 | gfs2_dinode_out(ip, dibh->b_data); |
777 | mark_inode_dirty(inode); |
778 | |
779 | brelse(dibh); |
780 | |
781 | out: |
782 | return error; |
783 | } |
784 | |
785 | static void calc_max_reserv(struct gfs2_inode *ip, loff_t max, loff_t *len, |
786 | unsigned int *data_blocks, unsigned int *ind_blocks) |
787 | { |
788 | const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); |
789 | unsigned int max_blocks = ip->i_alloc->al_rgd->rd_free_clone; |
790 | unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1); |
791 | |
792 | for (tmp = max_data; tmp > sdp->sd_diptrs;) { |
793 | tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs); |
794 | max_data -= tmp; |
795 | } |
796 | /* This calculation isn't the exact reverse of gfs2_write_calc_reserve, |
797 | so it might end up with fewer data blocks */ |
798 | if (max_data <= *data_blocks) |
799 | return; |
800 | *data_blocks = max_data; |
801 | *ind_blocks = max_blocks - max_data; |
802 | *len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift; |
803 | if (*len > max) { |
804 | *len = max; |
805 | gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks); |
806 | } |
807 | } |
808 | |
809 | static long gfs2_fallocate(struct file *file, int mode, loff_t offset, |
810 | loff_t len) |
811 | { |
812 | struct inode *inode = file->f_path.dentry->d_inode; |
813 | struct gfs2_sbd *sdp = GFS2_SB(inode); |
814 | struct gfs2_inode *ip = GFS2_I(inode); |
815 | unsigned int data_blocks = 0, ind_blocks = 0, rblocks; |
816 | loff_t bytes, max_bytes; |
817 | struct gfs2_alloc *al; |
818 | int error; |
819 | loff_t bsize_mask = ~((loff_t)sdp->sd_sb.sb_bsize - 1); |
820 | loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift; |
821 | next = (next + 1) << sdp->sd_sb.sb_bsize_shift; |
822 | |
823 | /* We only support the FALLOC_FL_KEEP_SIZE mode */ |
824 | if (mode & ~FALLOC_FL_KEEP_SIZE) |
825 | return -EOPNOTSUPP; |
826 | |
827 | offset &= bsize_mask; |
828 | |
829 | len = next - offset; |
830 | bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2; |
831 | if (!bytes) |
832 | bytes = UINT_MAX; |
833 | bytes &= bsize_mask; |
834 | if (bytes == 0) |
835 | bytes = sdp->sd_sb.sb_bsize; |
836 | |
837 | gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ip->i_gh); |
838 | error = gfs2_glock_nq(&ip->i_gh); |
839 | if (unlikely(error)) |
840 | goto out_uninit; |
841 | |
842 | if (!gfs2_write_alloc_required(ip, offset, len)) |
843 | goto out_unlock; |
844 | |
845 | while (len > 0) { |
846 | if (len < bytes) |
847 | bytes = len; |
848 | al = gfs2_alloc_get(ip); |
849 | if (!al) { |
850 | error = -ENOMEM; |
851 | goto out_unlock; |
852 | } |
853 | |
854 | error = gfs2_quota_lock_check(ip); |
855 | if (error) |
856 | goto out_alloc_put; |
857 | |
858 | retry: |
859 | gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks); |
860 | |
861 | al->al_requested = data_blocks + ind_blocks; |
862 | error = gfs2_inplace_reserve(ip); |
863 | if (error) { |
864 | if (error == -ENOSPC && bytes > sdp->sd_sb.sb_bsize) { |
865 | bytes >>= 1; |
866 | bytes &= bsize_mask; |
867 | if (bytes == 0) |
868 | bytes = sdp->sd_sb.sb_bsize; |
869 | goto retry; |
870 | } |
871 | goto out_qunlock; |
872 | } |
873 | max_bytes = bytes; |
874 | calc_max_reserv(ip, len, &max_bytes, &data_blocks, &ind_blocks); |
875 | al->al_requested = data_blocks + ind_blocks; |
876 | |
877 | rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA + |
878 | RES_RG_HDR + gfs2_rg_blocks(al); |
879 | if (gfs2_is_jdata(ip)) |
880 | rblocks += data_blocks ? data_blocks : 1; |
881 | |
882 | error = gfs2_trans_begin(sdp, rblocks, |
883 | PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize); |
884 | if (error) |
885 | goto out_trans_fail; |
886 | |
887 | error = fallocate_chunk(inode, offset, max_bytes, mode); |
888 | gfs2_trans_end(sdp); |
889 | |
890 | if (error) |
891 | goto out_trans_fail; |
892 | |
893 | len -= max_bytes; |
894 | offset += max_bytes; |
895 | gfs2_inplace_release(ip); |
896 | gfs2_quota_unlock(ip); |
897 | gfs2_alloc_put(ip); |
898 | } |
899 | goto out_unlock; |
900 | |
901 | out_trans_fail: |
902 | gfs2_inplace_release(ip); |
903 | out_qunlock: |
904 | gfs2_quota_unlock(ip); |
905 | out_alloc_put: |
906 | gfs2_alloc_put(ip); |
907 | out_unlock: |
908 | gfs2_glock_dq(&ip->i_gh); |
909 | out_uninit: |
910 | gfs2_holder_uninit(&ip->i_gh); |
911 | return error; |
912 | } |
913 | |
914 | #ifdef CONFIG_GFS2_FS_LOCKING_DLM |
915 | |
916 | /** |
917 | * gfs2_setlease - acquire/release a file lease |
918 | * @file: the file pointer |
919 | * @arg: lease type |
920 | * @fl: file lock |
921 | * |
922 | * We don't currently have a way to enforce a lease across the whole |
923 | * cluster; until we do, disable leases (by just returning -EINVAL), |
924 | * unless the administrator has requested purely local locking. |
925 | * |
926 | * Locking: called under lock_flocks |
927 | * |
928 | * Returns: errno |
929 | */ |
930 | |
931 | static int gfs2_setlease(struct file *file, long arg, struct file_lock **fl) |
932 | { |
933 | return -EINVAL; |
934 | } |
935 | |
936 | /** |
937 | * gfs2_lock - acquire/release a posix lock on a file |
938 | * @file: the file pointer |
939 | * @cmd: either modify or retrieve lock state, possibly wait |
940 | * @fl: type and range of lock |
941 | * |
942 | * Returns: errno |
943 | */ |
944 | |
945 | static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl) |
946 | { |
947 | struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); |
948 | struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host); |
949 | struct lm_lockstruct *ls = &sdp->sd_lockstruct; |
950 | |
951 | if (!(fl->fl_flags & FL_POSIX)) |
952 | return -ENOLCK; |
953 | if (__mandatory_lock(&ip->i_inode) && fl->fl_type != F_UNLCK) |
954 | return -ENOLCK; |
955 | |
956 | if (cmd == F_CANCELLK) { |
957 | /* Hack: */ |
958 | cmd = F_SETLK; |
959 | fl->fl_type = F_UNLCK; |
960 | } |
961 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) |
962 | return -EIO; |
963 | if (IS_GETLK(cmd)) |
964 | return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl); |
965 | else if (fl->fl_type == F_UNLCK) |
966 | return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl); |
967 | else |
968 | return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl); |
969 | } |
970 | |
971 | static int do_flock(struct file *file, int cmd, struct file_lock *fl) |
972 | { |
973 | struct gfs2_file *fp = file->private_data; |
974 | struct gfs2_holder *fl_gh = &fp->f_fl_gh; |
975 | struct gfs2_inode *ip = GFS2_I(file->f_path.dentry->d_inode); |
976 | struct gfs2_glock *gl; |
977 | unsigned int state; |
978 | int flags; |
979 | int error = 0; |
980 | |
981 | state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED; |
982 | flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE; |
983 | |
984 | mutex_lock(&fp->f_fl_mutex); |
985 | |
986 | gl = fl_gh->gh_gl; |
987 | if (gl) { |
988 | if (fl_gh->gh_state == state) |
989 | goto out; |
990 | flock_lock_file_wait(file, |
991 | &(struct file_lock){.fl_type = F_UNLCK}); |
992 | gfs2_glock_dq_wait(fl_gh); |
993 | gfs2_holder_reinit(state, flags, fl_gh); |
994 | } else { |
995 | error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr, |
996 | &gfs2_flock_glops, CREATE, &gl); |
997 | if (error) |
998 | goto out; |
999 | gfs2_holder_init(gl, state, flags, fl_gh); |
1000 | gfs2_glock_put(gl); |
1001 | } |
1002 | error = gfs2_glock_nq(fl_gh); |
1003 | if (error) { |
1004 | gfs2_holder_uninit(fl_gh); |
1005 | if (error == GLR_TRYFAILED) |
1006 | error = -EAGAIN; |
1007 | } else { |
1008 | error = flock_lock_file_wait(file, fl); |
1009 | gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error); |
1010 | } |
1011 | |
1012 | out: |
1013 | mutex_unlock(&fp->f_fl_mutex); |
1014 | return error; |
1015 | } |
1016 | |
1017 | static void do_unflock(struct file *file, struct file_lock *fl) |
1018 | { |
1019 | struct gfs2_file *fp = file->private_data; |
1020 | struct gfs2_holder *fl_gh = &fp->f_fl_gh; |
1021 | |
1022 | mutex_lock(&fp->f_fl_mutex); |
1023 | flock_lock_file_wait(file, fl); |
1024 | if (fl_gh->gh_gl) { |
1025 | gfs2_glock_dq_wait(fl_gh); |
1026 | gfs2_holder_uninit(fl_gh); |
1027 | } |
1028 | mutex_unlock(&fp->f_fl_mutex); |
1029 | } |
1030 | |
1031 | /** |
1032 | * gfs2_flock - acquire/release a flock lock on a file |
1033 | * @file: the file pointer |
1034 | * @cmd: either modify or retrieve lock state, possibly wait |
1035 | * @fl: type and range of lock |
1036 | * |
1037 | * Returns: errno |
1038 | */ |
1039 | |
1040 | static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl) |
1041 | { |
1042 | if (!(fl->fl_flags & FL_FLOCK)) |
1043 | return -ENOLCK; |
1044 | if (fl->fl_type & LOCK_MAND) |
1045 | return -EOPNOTSUPP; |
1046 | |
1047 | if (fl->fl_type == F_UNLCK) { |
1048 | do_unflock(file, fl); |
1049 | return 0; |
1050 | } else { |
1051 | return do_flock(file, cmd, fl); |
1052 | } |
1053 | } |
1054 | |
1055 | const struct file_operations gfs2_file_fops = { |
1056 | .llseek = gfs2_llseek, |
1057 | .read = do_sync_read, |
1058 | .aio_read = generic_file_aio_read, |
1059 | .write = do_sync_write, |
1060 | .aio_write = gfs2_file_aio_write, |
1061 | .unlocked_ioctl = gfs2_ioctl, |
1062 | .mmap = gfs2_mmap, |
1063 | .open = gfs2_open, |
1064 | .release = gfs2_close, |
1065 | .fsync = gfs2_fsync, |
1066 | .lock = gfs2_lock, |
1067 | .flock = gfs2_flock, |
1068 | .splice_read = generic_file_splice_read, |
1069 | .splice_write = generic_file_splice_write, |
1070 | .setlease = gfs2_setlease, |
1071 | .fallocate = gfs2_fallocate, |
1072 | }; |
1073 | |
1074 | const struct file_operations gfs2_dir_fops = { |
1075 | .readdir = gfs2_readdir, |
1076 | .unlocked_ioctl = gfs2_ioctl, |
1077 | .open = gfs2_open, |
1078 | .release = gfs2_close, |
1079 | .fsync = gfs2_fsync, |
1080 | .lock = gfs2_lock, |
1081 | .flock = gfs2_flock, |
1082 | .llseek = default_llseek, |
1083 | }; |
1084 | |
1085 | #endif /* CONFIG_GFS2_FS_LOCKING_DLM */ |
1086 | |
1087 | const struct file_operations gfs2_file_fops_nolock = { |
1088 | .llseek = gfs2_llseek, |
1089 | .read = do_sync_read, |
1090 | .aio_read = generic_file_aio_read, |
1091 | .write = do_sync_write, |
1092 | .aio_write = gfs2_file_aio_write, |
1093 | .unlocked_ioctl = gfs2_ioctl, |
1094 | .mmap = gfs2_mmap, |
1095 | .open = gfs2_open, |
1096 | .release = gfs2_close, |
1097 | .fsync = gfs2_fsync, |
1098 | .splice_read = generic_file_splice_read, |
1099 | .splice_write = generic_file_splice_write, |
1100 | .setlease = generic_setlease, |
1101 | .fallocate = gfs2_fallocate, |
1102 | }; |
1103 | |
1104 | const struct file_operations gfs2_dir_fops_nolock = { |
1105 | .readdir = gfs2_readdir, |
1106 | .unlocked_ioctl = gfs2_ioctl, |
1107 | .open = gfs2_open, |
1108 | .release = gfs2_close, |
1109 | .fsync = gfs2_fsync, |
1110 | .llseek = default_llseek, |
1111 | }; |
1112 | |
1113 |
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