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GUI: Fix Tomato RAF theme for all builds. Compilation typo.
[tomato.git] / release / src-rt-6.x.4708 / linux / linux-2.6.36 / fs / gfs2 / dir.c
blob69d5939f2b50c07d5ce24ec519191749de69de61
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 /*
11 * Implements Extendible Hashing as described in:
12 * "Extendible Hashing" by Fagin, et al in
13 * __ACM Trans. on Database Systems__, Sept 1979.
14 *
15 *
16 * Here's the layout of dirents which is essentially the same as that of ext2
17 * within a single block. The field de_name_len is the number of bytes
18 * actually required for the name (no null terminator). The field de_rec_len
19 * is the number of bytes allocated to the dirent. The offset of the next
20 * dirent in the block is (dirent + dirent->de_rec_len). When a dirent is
21 * deleted, the preceding dirent inherits its allocated space, ie
22 * prev->de_rec_len += deleted->de_rec_len. Since the next dirent is obtained
23 * by adding de_rec_len to the current dirent, this essentially causes the
24 * deleted dirent to get jumped over when iterating through all the dirents.
25 *
26 * When deleting the first dirent in a block, there is no previous dirent so
27 * the field de_ino is set to zero to designate it as deleted. When allocating
28 * a dirent, gfs2_dirent_alloc iterates through the dirents in a block. If the
29 * first dirent has (de_ino == 0) and de_rec_len is large enough, this first
30 * dirent is allocated. Otherwise it must go through all the 'used' dirents
31 * searching for one in which the amount of total space minus the amount of
32 * used space will provide enough space for the new dirent.
33 *
34 * There are two types of blocks in which dirents reside. In a stuffed dinode,
35 * the dirents begin at offset sizeof(struct gfs2_dinode) from the beginning of
36 * the block. In leaves, they begin at offset sizeof(struct gfs2_leaf) from the
37 * beginning of the leaf block. The dirents reside in leaves when
38 *
39 * dip->i_diskflags & GFS2_DIF_EXHASH is true
40 *
41 * Otherwise, the dirents are "linear", within a single stuffed dinode block.
42 *
43 * When the dirents are in leaves, the actual contents of the directory file are
44 * used as an array of 64-bit block pointers pointing to the leaf blocks. The
45 * dirents are NOT in the directory file itself. There can be more than one
46 * block pointer in the array that points to the same leaf. In fact, when a
47 * directory is first converted from linear to exhash, all of the pointers
48 * point to the same leaf.
49 *
50 * When a leaf is completely full, the size of the hash table can be
51 * doubled unless it is already at the maximum size which is hard coded into
52 * GFS2_DIR_MAX_DEPTH. After that, leaves are chained together in a linked list,
53 * but never before the maximum hash table size has been reached.
54 */
55
56 #include <linux/slab.h>
57 #include <linux/spinlock.h>
58 #include <linux/buffer_head.h>
59 #include <linux/sort.h>
60 #include <linux/gfs2_ondisk.h>
61 #include <linux/crc32.h>
62 #include <linux/vmalloc.h>
63
64 #include "gfs2.h"
65 #include "incore.h"
66 #include "dir.h"
67 #include "glock.h"
68 #include "inode.h"
69 #include "meta_io.h"
70 #include "quota.h"
71 #include "rgrp.h"
72 #include "trans.h"
73 #include "bmap.h"
74 #include "util.h"
75
76 #define IS_LEAF 1 /* Hashed (leaf) directory */
77 #define IS_DINODE 2 /* Linear (stuffed dinode block) directory */
78
79 #define gfs2_disk_hash2offset(h) (((u64)(h)) >> 1)
80 #define gfs2_dir_offset2hash(p) ((u32)(((u64)(p)) << 1))
81
82 typedef int (*leaf_call_t) (struct gfs2_inode *dip, u32 index, u32 len,
83 u64 leaf_no, void *data);
84 typedef int (*gfs2_dscan_t)(const struct gfs2_dirent *dent,
85 const struct qstr *name, void *opaque);
86
87
88 int gfs2_dir_get_new_buffer(struct gfs2_inode *ip, u64 block,
89 struct buffer_head **bhp)
90 {
91 struct buffer_head *bh;
92
93 bh = gfs2_meta_new(ip->i_gl, block);
94 gfs2_trans_add_bh(ip->i_gl, bh, 1);
95 gfs2_metatype_set(bh, GFS2_METATYPE_JD, GFS2_FORMAT_JD);
96 gfs2_buffer_clear_tail(bh, sizeof(struct gfs2_meta_header));
97 *bhp = bh;
98 return 0;
99 }
100
101 static int gfs2_dir_get_existing_buffer(struct gfs2_inode *ip, u64 block,
102 struct buffer_head **bhp)
103 {
104 struct buffer_head *bh;
105 int error;
106
107 error = gfs2_meta_read(ip->i_gl, block, DIO_WAIT, &bh);
108 if (error)
109 return error;
110 if (gfs2_metatype_check(GFS2_SB(&ip->i_inode), bh, GFS2_METATYPE_JD)) {
111 brelse(bh);
112 return -EIO;
113 }
114 *bhp = bh;
115 return 0;
116 }
117
118 static int gfs2_dir_write_stuffed(struct gfs2_inode *ip, const char *buf,
119 unsigned int offset, unsigned int size)
120 {
121 struct buffer_head *dibh;
122 int error;
123
124 error = gfs2_meta_inode_buffer(ip, &dibh);
125 if (error)
126 return error;
127
128 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
129 memcpy(dibh->b_data + offset + sizeof(struct gfs2_dinode), buf, size);
130 if (ip->i_disksize < offset + size)
131 ip->i_disksize = offset + size;
132 ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
133 gfs2_dinode_out(ip, dibh->b_data);
134
135 brelse(dibh);
136
137 return size;
138 }
139
140
141
142 /**
143 * gfs2_dir_write_data - Write directory information to the inode
144 * @ip: The GFS2 inode
145 * @buf: The buffer containing information to be written
146 * @offset: The file offset to start writing at
147 * @size: The amount of data to write
148 *
149 * Returns: The number of bytes correctly written or error code
150 */
151 static int gfs2_dir_write_data(struct gfs2_inode *ip, const char *buf,
152 u64 offset, unsigned int size)
153 {
154 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
155 struct buffer_head *dibh;
156 u64 lblock, dblock;
157 u32 extlen = 0;
158 unsigned int o;
159 int copied = 0;
160 int error = 0;
161 int new = 0;
162
163 if (!size)
164 return 0;
165
166 if (gfs2_is_stuffed(ip) &&
167 offset + size <= sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode))
168 return gfs2_dir_write_stuffed(ip, buf, (unsigned int)offset,
169 size);
170
171 if (gfs2_assert_warn(sdp, gfs2_is_jdata(ip)))
172 return -EINVAL;
173
174 if (gfs2_is_stuffed(ip)) {
175 error = gfs2_unstuff_dinode(ip, NULL);
176 if (error)
177 return error;
178 }
179
180 lblock = offset;
181 o = do_div(lblock, sdp->sd_jbsize) + sizeof(struct gfs2_meta_header);
182
183 while (copied < size) {
184 unsigned int amount;
185 struct buffer_head *bh;
186
187 amount = size - copied;
188 if (amount > sdp->sd_sb.sb_bsize - o)
189 amount = sdp->sd_sb.sb_bsize - o;
190
191 if (!extlen) {
192 new = 1;
193 error = gfs2_extent_map(&ip->i_inode, lblock, &new,
194 &dblock, &extlen);
195 if (error)
196 goto fail;
197 error = -EIO;
198 if (gfs2_assert_withdraw(sdp, dblock))
199 goto fail;
200 }
201
202 if (amount == sdp->sd_jbsize || new)
203 error = gfs2_dir_get_new_buffer(ip, dblock, &bh);
204 else
205 error = gfs2_dir_get_existing_buffer(ip, dblock, &bh);
206
207 if (error)
208 goto fail;
209
210 gfs2_trans_add_bh(ip->i_gl, bh, 1);
211 memcpy(bh->b_data + o, buf, amount);
212 brelse(bh);
213
214 buf += amount;
215 copied += amount;
216 lblock++;
217 dblock++;
218 extlen--;
219
220 o = sizeof(struct gfs2_meta_header);
221 }
222
223 out:
224 error = gfs2_meta_inode_buffer(ip, &dibh);
225 if (error)
226 return error;
227
228 if (ip->i_disksize < offset + copied)
229 ip->i_disksize = offset + copied;
230 ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
231
232 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
233 gfs2_dinode_out(ip, dibh->b_data);
234 brelse(dibh);
235
236 return copied;
237 fail:
238 if (copied)
239 goto out;
240 return error;
241 }
242
243 static int gfs2_dir_read_stuffed(struct gfs2_inode *ip, char *buf,
244 u64 offset, unsigned int size)
245 {
246 struct buffer_head *dibh;
247 int error;
248
249 error = gfs2_meta_inode_buffer(ip, &dibh);
250 if (!error) {
251 offset += sizeof(struct gfs2_dinode);
252 memcpy(buf, dibh->b_data + offset, size);
253 brelse(dibh);
254 }
255
256 return (error) ? error : size;
257 }
258
259
260 /**
261 * gfs2_dir_read_data - Read a data from a directory inode
262 * @ip: The GFS2 Inode
263 * @buf: The buffer to place result into
264 * @offset: File offset to begin jdata_readng from
265 * @size: Amount of data to transfer
266 *
267 * Returns: The amount of data actually copied or the error
268 */
269 static int gfs2_dir_read_data(struct gfs2_inode *ip, char *buf, u64 offset,
270 unsigned int size, unsigned ra)
271 {
272 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
273 u64 lblock, dblock;
274 u32 extlen = 0;
275 unsigned int o;
276 int copied = 0;
277 int error = 0;
278
279 if (offset >= ip->i_disksize)
280 return 0;
281
282 if (offset + size > ip->i_disksize)
283 size = ip->i_disksize - offset;
284
285 if (!size)
286 return 0;
287
288 if (gfs2_is_stuffed(ip))
289 return gfs2_dir_read_stuffed(ip, buf, offset, size);
290
291 if (gfs2_assert_warn(sdp, gfs2_is_jdata(ip)))
292 return -EINVAL;
293
294 lblock = offset;
295 o = do_div(lblock, sdp->sd_jbsize) + sizeof(struct gfs2_meta_header);
296
297 while (copied < size) {
298 unsigned int amount;
299 struct buffer_head *bh;
300 int new;
301
302 amount = size - copied;
303 if (amount > sdp->sd_sb.sb_bsize - o)
304 amount = sdp->sd_sb.sb_bsize - o;
305
306 if (!extlen) {
307 new = 0;
308 error = gfs2_extent_map(&ip->i_inode, lblock, &new,
309 &dblock, &extlen);
310 if (error || !dblock)
311 goto fail;
312 BUG_ON(extlen < 1);
313 if (!ra)
314 extlen = 1;
315 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
316 } else {
317 error = gfs2_meta_read(ip->i_gl, dblock, DIO_WAIT, &bh);
318 if (error)
319 goto fail;
320 }
321 error = gfs2_metatype_check(sdp, bh, GFS2_METATYPE_JD);
322 if (error) {
323 brelse(bh);
324 goto fail;
325 }
326 dblock++;
327 extlen--;
328 memcpy(buf, bh->b_data + o, amount);
329 brelse(bh);
330 buf += amount;
331 copied += amount;
332 lblock++;
333 o = sizeof(struct gfs2_meta_header);
334 }
335
336 return copied;
337 fail:
338 return (copied) ? copied : error;
339 }
340
341 static inline int gfs2_dirent_sentinel(const struct gfs2_dirent *dent)
342 {
343 return dent->de_inum.no_addr == 0 || dent->de_inum.no_formal_ino == 0;
344 }
345
346 static inline int __gfs2_dirent_find(const struct gfs2_dirent *dent,
347 const struct qstr *name, int ret)
348 {
349 if (!gfs2_dirent_sentinel(dent) &&
350 be32_to_cpu(dent->de_hash) == name->hash &&
351 be16_to_cpu(dent->de_name_len) == name->len &&
352 memcmp(dent+1, name->name, name->len) == 0)
353 return ret;
354 return 0;
355 }
356
357 static int gfs2_dirent_find(const struct gfs2_dirent *dent,
358 const struct qstr *name,
359 void *opaque)
360 {
361 return __gfs2_dirent_find(dent, name, 1);
362 }
363
364 static int gfs2_dirent_prev(const struct gfs2_dirent *dent,
365 const struct qstr *name,
366 void *opaque)
367 {
368 return __gfs2_dirent_find(dent, name, 2);
369 }
370
371 /*
372 * name->name holds ptr to start of block.
373 * name->len holds size of block.
374 */
375 static int gfs2_dirent_last(const struct gfs2_dirent *dent,
376 const struct qstr *name,
377 void *opaque)
378 {
379 const char *start = name->name;
380 const char *end = (const char *)dent + be16_to_cpu(dent->de_rec_len);
381 if (name->len == (end - start))
382 return 1;
383 return 0;
384 }
385
386 static int gfs2_dirent_find_space(const struct gfs2_dirent *dent,
387 const struct qstr *name,
388 void *opaque)
389 {
390 unsigned required = GFS2_DIRENT_SIZE(name->len);
391 unsigned actual = GFS2_DIRENT_SIZE(be16_to_cpu(dent->de_name_len));
392 unsigned totlen = be16_to_cpu(dent->de_rec_len);
393
394 if (gfs2_dirent_sentinel(dent))
395 actual = 0;
396 if (totlen - actual >= required)
397 return 1;
398 return 0;
399 }
400
401 struct dirent_gather {
402 const struct gfs2_dirent **pdent;
403 unsigned offset;
404 };
405
406 static int gfs2_dirent_gather(const struct gfs2_dirent *dent,
407 const struct qstr *name,
408 void *opaque)
409 {
410 struct dirent_gather *g = opaque;
411 if (!gfs2_dirent_sentinel(dent)) {
412 g->pdent[g->offset++] = dent;
413 }
414 return 0;
415 }
416
417 /*
418 * Other possible things to check:
419 * - Inode located within filesystem size (and on valid block)
420 * - Valid directory entry type
421 * Not sure how heavy-weight we want to make this... could also check
422 * hash is correct for example, but that would take a lot of extra time.
423 * For now the most important thing is to check that the various sizes
424 * are correct.
425 */
426 static int gfs2_check_dirent(struct gfs2_dirent *dent, unsigned int offset,
427 unsigned int size, unsigned int len, int first)
428 {
429 const char *msg = "gfs2_dirent too small";
430 if (unlikely(size < sizeof(struct gfs2_dirent)))
431 goto error;
432 msg = "gfs2_dirent misaligned";
433 if (unlikely(offset & 0x7))
434 goto error;
435 msg = "gfs2_dirent points beyond end of block";
436 if (unlikely(offset + size > len))
437 goto error;
438 msg = "zero inode number";
439 if (unlikely(!first && gfs2_dirent_sentinel(dent)))
440 goto error;
441 msg = "name length is greater than space in dirent";
442 if (!gfs2_dirent_sentinel(dent) &&
443 unlikely(sizeof(struct gfs2_dirent)+be16_to_cpu(dent->de_name_len) >
444 size))
445 goto error;
446 return 0;
447 error:
448 printk(KERN_WARNING "gfs2_check_dirent: %s (%s)\n", msg,
449 first ? "first in block" : "not first in block");
450 return -EIO;
451 }
452
453 static int gfs2_dirent_offset(const void *buf)
454 {
455 const struct gfs2_meta_header *h = buf;
456 int offset;
457
458 BUG_ON(buf == NULL);
459
460 switch(be32_to_cpu(h->mh_type)) {
461 case GFS2_METATYPE_LF:
462 offset = sizeof(struct gfs2_leaf);
463 break;
464 case GFS2_METATYPE_DI:
465 offset = sizeof(struct gfs2_dinode);
466 break;
467 default:
468 goto wrong_type;
469 }
470 return offset;
471 wrong_type:
472 printk(KERN_WARNING "gfs2_scan_dirent: wrong block type %u\n",
473 be32_to_cpu(h->mh_type));
474 return -1;
475 }
476
477 static struct gfs2_dirent *gfs2_dirent_scan(struct inode *inode, void *buf,
478 unsigned int len, gfs2_dscan_t scan,
479 const struct qstr *name,
480 void *opaque)
481 {
482 struct gfs2_dirent *dent, *prev;
483 unsigned offset;
484 unsigned size;
485 int ret = 0;
486
487 ret = gfs2_dirent_offset(buf);
488 if (ret < 0)
489 goto consist_inode;
490
491 offset = ret;
492 prev = NULL;
493 dent = buf + offset;
494 size = be16_to_cpu(dent->de_rec_len);
495 if (gfs2_check_dirent(dent, offset, size, len, 1))
496 goto consist_inode;
497 do {
498 ret = scan(dent, name, opaque);
499 if (ret)
500 break;
501 offset += size;
502 if (offset == len)
503 break;
504 prev = dent;
505 dent = buf + offset;
506 size = be16_to_cpu(dent->de_rec_len);
507 if (gfs2_check_dirent(dent, offset, size, len, 0))
508 goto consist_inode;
509 } while(1);
510
511 switch(ret) {
512 case 0:
513 return NULL;
514 case 1:
515 return dent;
516 case 2:
517 return prev ? prev : dent;
518 default:
519 BUG_ON(ret > 0);
520 return ERR_PTR(ret);
521 }
522
523 consist_inode:
524 gfs2_consist_inode(GFS2_I(inode));
525 return ERR_PTR(-EIO);
526 }
527
528 static int dirent_check_reclen(struct gfs2_inode *dip,
529 const struct gfs2_dirent *d, const void *end_p)
530 {
531 const void *ptr = d;
532 u16 rec_len = be16_to_cpu(d->de_rec_len);
533
534 if (unlikely(rec_len < sizeof(struct gfs2_dirent)))
535 goto broken;
536 ptr += rec_len;
537 if (ptr < end_p)
538 return rec_len;
539 if (ptr == end_p)
540 return -ENOENT;
541 broken:
542 gfs2_consist_inode(dip);
543 return -EIO;
544 }
545
546 /**
547 * dirent_next - Next dirent
548 * @dip: the directory
549 * @bh: The buffer
550 * @dent: Pointer to list of dirents
551 *
552 * Returns: 0 on success, error code otherwise
553 */
554
555 static int dirent_next(struct gfs2_inode *dip, struct buffer_head *bh,
556 struct gfs2_dirent **dent)
557 {
558 struct gfs2_dirent *cur = *dent, *tmp;
559 char *bh_end = bh->b_data + bh->b_size;
560 int ret;
561
562 ret = dirent_check_reclen(dip, cur, bh_end);
563 if (ret < 0)
564 return ret;
565
566 tmp = (void *)cur + ret;
567 ret = dirent_check_reclen(dip, tmp, bh_end);
568 if (ret == -EIO)
569 return ret;
570
571 /* Only the first dent could ever have de_inum.no_addr == 0 */
572 if (gfs2_dirent_sentinel(tmp)) {
573 gfs2_consist_inode(dip);
574 return -EIO;
575 }
576
577 *dent = tmp;
578 return 0;
579 }
580
581 /**
582 * dirent_del - Delete a dirent
583 * @dip: The GFS2 inode
584 * @bh: The buffer
585 * @prev: The previous dirent
586 * @cur: The current dirent
587 *
588 */
589
590 static void dirent_del(struct gfs2_inode *dip, struct buffer_head *bh,
591 struct gfs2_dirent *prev, struct gfs2_dirent *cur)
592 {
593 u16 cur_rec_len, prev_rec_len;
594
595 if (gfs2_dirent_sentinel(cur)) {
596 gfs2_consist_inode(dip);
597 return;
598 }
599
600 gfs2_trans_add_bh(dip->i_gl, bh, 1);
601
602 /* If there is no prev entry, this is the first entry in the block.
603 The de_rec_len is already as big as it needs to be. Just zero
604 out the inode number and return. */
605
606 if (!prev) {
607 cur->de_inum.no_addr = 0;
608 cur->de_inum.no_formal_ino = 0;
609 return;
610 }
611
612 /* Combine this dentry with the previous one. */
613
614 prev_rec_len = be16_to_cpu(prev->de_rec_len);
615 cur_rec_len = be16_to_cpu(cur->de_rec_len);
616
617 if ((char *)prev + prev_rec_len != (char *)cur)
618 gfs2_consist_inode(dip);
619 if ((char *)cur + cur_rec_len > bh->b_data + bh->b_size)
620 gfs2_consist_inode(dip);
621
622 prev_rec_len += cur_rec_len;
623 prev->de_rec_len = cpu_to_be16(prev_rec_len);
624 }
625
626 /*
627 * Takes a dent from which to grab space as an argument. Returns the
628 * newly created dent.
629 */
630 static struct gfs2_dirent *gfs2_init_dirent(struct inode *inode,
631 struct gfs2_dirent *dent,
632 const struct qstr *name,
633 struct buffer_head *bh)
634 {
635 struct gfs2_inode *ip = GFS2_I(inode);
636 struct gfs2_dirent *ndent;
637 unsigned offset = 0, totlen;
638
639 if (!gfs2_dirent_sentinel(dent))
640 offset = GFS2_DIRENT_SIZE(be16_to_cpu(dent->de_name_len));
641 totlen = be16_to_cpu(dent->de_rec_len);
642 BUG_ON(offset + name->len > totlen);
643 gfs2_trans_add_bh(ip->i_gl, bh, 1);
644 ndent = (struct gfs2_dirent *)((char *)dent + offset);
645 dent->de_rec_len = cpu_to_be16(offset);
646 gfs2_qstr2dirent(name, totlen - offset, ndent);
647 return ndent;
648 }
649
650 static struct gfs2_dirent *gfs2_dirent_alloc(struct inode *inode,
651 struct buffer_head *bh,
652 const struct qstr *name)
653 {
654 struct gfs2_dirent *dent;
655 dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size,
656 gfs2_dirent_find_space, name, NULL);
657 if (!dent || IS_ERR(dent))
658 return dent;
659 return gfs2_init_dirent(inode, dent, name, bh);
660 }
661
662 static int get_leaf(struct gfs2_inode *dip, u64 leaf_no,
663 struct buffer_head **bhp)
664 {
665 int error;
666
667 error = gfs2_meta_read(dip->i_gl, leaf_no, DIO_WAIT, bhp);
668 if (!error && gfs2_metatype_check(GFS2_SB(&dip->i_inode), *bhp, GFS2_METATYPE_LF)) {
669 /* printk(KERN_INFO "block num=%llu\n", leaf_no); */
670 error = -EIO;
671 }
672
673 return error;
674 }
675
676 /**
677 * get_leaf_nr - Get a leaf number associated with the index
678 * @dip: The GFS2 inode
679 * @index:
680 * @leaf_out:
681 *
682 * Returns: 0 on success, error code otherwise
683 */
684
685 static int get_leaf_nr(struct gfs2_inode *dip, u32 index,
686 u64 *leaf_out)
687 {
688 __be64 leaf_no;
689 int error;
690
691 error = gfs2_dir_read_data(dip, (char *)&leaf_no,
692 index * sizeof(__be64),
693 sizeof(__be64), 0);
694 if (error != sizeof(u64))
695 return (error < 0) ? error : -EIO;
696
697 *leaf_out = be64_to_cpu(leaf_no);
698
699 return 0;
700 }
701
702 static int get_first_leaf(struct gfs2_inode *dip, u32 index,
703 struct buffer_head **bh_out)
704 {
705 u64 leaf_no;
706 int error;
707
708 error = get_leaf_nr(dip, index, &leaf_no);
709 if (!error)
710 error = get_leaf(dip, leaf_no, bh_out);
711
712 return error;
713 }
714
715 static struct gfs2_dirent *gfs2_dirent_search(struct inode *inode,
716 const struct qstr *name,
717 gfs2_dscan_t scan,
718 struct buffer_head **pbh)
719 {
720 struct buffer_head *bh;
721 struct gfs2_dirent *dent;
722 struct gfs2_inode *ip = GFS2_I(inode);
723 int error;
724
725 if (ip->i_diskflags & GFS2_DIF_EXHASH) {
726 struct gfs2_leaf *leaf;
727 unsigned hsize = 1 << ip->i_depth;
728 unsigned index;
729 u64 ln;
730 if (hsize * sizeof(u64) != ip->i_disksize) {
731 gfs2_consist_inode(ip);
732 return ERR_PTR(-EIO);
733 }
734
735 index = name->hash >> (32 - ip->i_depth);
736 error = get_first_leaf(ip, index, &bh);
737 if (error)
738 return ERR_PTR(error);
739 do {
740 dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size,
741 scan, name, NULL);
742 if (dent)
743 goto got_dent;
744 leaf = (struct gfs2_leaf *)bh->b_data;
745 ln = be64_to_cpu(leaf->lf_next);
746 brelse(bh);
747 if (!ln)
748 break;
749
750 error = get_leaf(ip, ln, &bh);
751 } while(!error);
752
753 return error ? ERR_PTR(error) : NULL;
754 }
755
756
757 error = gfs2_meta_inode_buffer(ip, &bh);
758 if (error)
759 return ERR_PTR(error);
760 dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size, scan, name, NULL);
761 got_dent:
762 if (unlikely(dent == NULL || IS_ERR(dent))) {
763 brelse(bh);
764 bh = NULL;
765 }
766 *pbh = bh;
767 return dent;
768 }
769
770 static struct gfs2_leaf *new_leaf(struct inode *inode, struct buffer_head **pbh, u16 depth)
771 {
772 struct gfs2_inode *ip = GFS2_I(inode);
773 unsigned int n = 1;
774 u64 bn;
775 int error;
776 struct buffer_head *bh;
777 struct gfs2_leaf *leaf;
778 struct gfs2_dirent *dent;
779 struct qstr name = { .name = "", .len = 0, .hash = 0 };
780
781 error = gfs2_alloc_block(ip, &bn, &n);
782 if (error)
783 return NULL;
784 bh = gfs2_meta_new(ip->i_gl, bn);
785 if (!bh)
786 return NULL;
787
788 gfs2_trans_add_unrevoke(GFS2_SB(inode), bn, 1);
789 gfs2_trans_add_bh(ip->i_gl, bh, 1);
790 gfs2_metatype_set(bh, GFS2_METATYPE_LF, GFS2_FORMAT_LF);
791 leaf = (struct gfs2_leaf *)bh->b_data;
792 leaf->lf_depth = cpu_to_be16(depth);
793 leaf->lf_entries = 0;
794 leaf->lf_dirent_format = cpu_to_be32(GFS2_FORMAT_DE);
795 leaf->lf_next = 0;
796 memset(leaf->lf_reserved, 0, sizeof(leaf->lf_reserved));
797 dent = (struct gfs2_dirent *)(leaf+1);
798 gfs2_qstr2dirent(&name, bh->b_size - sizeof(struct gfs2_leaf), dent);
799 *pbh = bh;
800 return leaf;
801 }
802
803 /**
804 * dir_make_exhash - Convert a stuffed directory into an ExHash directory
805 * @dip: The GFS2 inode
806 *
807 * Returns: 0 on success, error code otherwise
808 */
809
810 static int dir_make_exhash(struct inode *inode)
811 {
812 struct gfs2_inode *dip = GFS2_I(inode);
813 struct gfs2_sbd *sdp = GFS2_SB(inode);
814 struct gfs2_dirent *dent;
815 struct qstr args;
816 struct buffer_head *bh, *dibh;
817 struct gfs2_leaf *leaf;
818 int y;
819 u32 x;
820 __be64 *lp;
821 u64 bn;
822 int error;
823
824 error = gfs2_meta_inode_buffer(dip, &dibh);
825 if (error)
826 return error;
827
828 /* Turn over a new leaf */
829
830 leaf = new_leaf(inode, &bh, 0);
831 if (!leaf)
832 return -ENOSPC;
833 bn = bh->b_blocknr;
834
835 gfs2_assert(sdp, dip->i_entries < (1 << 16));
836 leaf->lf_entries = cpu_to_be16(dip->i_entries);
837
838 /* Copy dirents */
839
840 gfs2_buffer_copy_tail(bh, sizeof(struct gfs2_leaf), dibh,
841 sizeof(struct gfs2_dinode));
842
843 /* Find last entry */
844
845 x = 0;
846 args.len = bh->b_size - sizeof(struct gfs2_dinode) +
847 sizeof(struct gfs2_leaf);
848 args.name = bh->b_data;
849 dent = gfs2_dirent_scan(&dip->i_inode, bh->b_data, bh->b_size,
850 gfs2_dirent_last, &args, NULL);
851 if (!dent) {
852 brelse(bh);
853 brelse(dibh);
854 return -EIO;
855 }
856 if (IS_ERR(dent)) {
857 brelse(bh);
858 brelse(dibh);
859 return PTR_ERR(dent);
860 }
861
862 /* Adjust the last dirent's record length
863 (Remember that dent still points to the last entry.) */
864
865 dent->de_rec_len = cpu_to_be16(be16_to_cpu(dent->de_rec_len) +
866 sizeof(struct gfs2_dinode) -
867 sizeof(struct gfs2_leaf));
868
869 brelse(bh);
870
871 /* We're done with the new leaf block, now setup the new
872 hash table. */
873
874 gfs2_trans_add_bh(dip->i_gl, dibh, 1);
875 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
876
877 lp = (__be64 *)(dibh->b_data + sizeof(struct gfs2_dinode));
878
879 for (x = sdp->sd_hash_ptrs; x--; lp++)
880 *lp = cpu_to_be64(bn);
881
882 dip->i_disksize = sdp->sd_sb.sb_bsize / 2;
883 gfs2_add_inode_blocks(&dip->i_inode, 1);
884 dip->i_diskflags |= GFS2_DIF_EXHASH;
885
886 for (x = sdp->sd_hash_ptrs, y = -1; x; x >>= 1, y++) ;
887 dip->i_depth = y;
888
889 gfs2_dinode_out(dip, dibh->b_data);
890
891 brelse(dibh);
892
893 return 0;
894 }
895
896 /**
897 * dir_split_leaf - Split a leaf block into two
898 * @dip: The GFS2 inode
899 * @index:
900 * @leaf_no:
901 *
902 * Returns: 0 on success, error code on failure
903 */
904
905 static int dir_split_leaf(struct inode *inode, const struct qstr *name)
906 {
907 struct gfs2_inode *dip = GFS2_I(inode);
908 struct buffer_head *nbh, *obh, *dibh;
909 struct gfs2_leaf *nleaf, *oleaf;
910 struct gfs2_dirent *dent = NULL, *prev = NULL, *next = NULL, *new;
911 u32 start, len, half_len, divider;
912 u64 bn, leaf_no;
913 __be64 *lp;
914 u32 index;
915 int x, moved = 0;
916 int error;
917
918 index = name->hash >> (32 - dip->i_depth);
919 error = get_leaf_nr(dip, index, &leaf_no);
920 if (error)
921 return error;
922
923 /* Get the old leaf block */
924 error = get_leaf(dip, leaf_no, &obh);
925 if (error)
926 return error;
927
928 oleaf = (struct gfs2_leaf *)obh->b_data;
929 if (dip->i_depth == be16_to_cpu(oleaf->lf_depth)) {
930 brelse(obh);
931 return 1; /* can't split */
932 }
933
934 gfs2_trans_add_bh(dip->i_gl, obh, 1);
935
936 nleaf = new_leaf(inode, &nbh, be16_to_cpu(oleaf->lf_depth) + 1);
937 if (!nleaf) {
938 brelse(obh);
939 return -ENOSPC;
940 }
941 bn = nbh->b_blocknr;
942
943 /* Compute the start and len of leaf pointers in the hash table. */
944 len = 1 << (dip->i_depth - be16_to_cpu(oleaf->lf_depth));
945 half_len = len >> 1;
946 if (!half_len) {
947 printk(KERN_WARNING "i_depth %u lf_depth %u index %u\n", dip->i_depth, be16_to_cpu(oleaf->lf_depth), index);
948 gfs2_consist_inode(dip);
949 error = -EIO;
950 goto fail_brelse;
951 }
952
953 start = (index & ~(len - 1));
954
955 /* Change the pointers.
956 Don't bother distinguishing stuffed from non-stuffed.
957 This code is complicated enough already. */
958 lp = kmalloc(half_len * sizeof(__be64), GFP_NOFS);
959 if (!lp) {
960 error = -ENOMEM;
961 goto fail_brelse;
962 }
963
964 /* Change the pointers */
965 for (x = 0; x < half_len; x++)
966 lp[x] = cpu_to_be64(bn);
967
968 error = gfs2_dir_write_data(dip, (char *)lp, start * sizeof(u64),
969 half_len * sizeof(u64));
970 if (error != half_len * sizeof(u64)) {
971 if (error >= 0)
972 error = -EIO;
973 goto fail_lpfree;
974 }
975
976 kfree(lp);
977
978 /* Compute the divider */
979 divider = (start + half_len) << (32 - dip->i_depth);
980
981 /* Copy the entries */
982 dent = (struct gfs2_dirent *)(obh->b_data + sizeof(struct gfs2_leaf));
983
984 do {
985 next = dent;
986 if (dirent_next(dip, obh, &next))
987 next = NULL;
988
989 if (!gfs2_dirent_sentinel(dent) &&
990 be32_to_cpu(dent->de_hash) < divider) {
991 struct qstr str;
992 str.name = (char*)(dent+1);
993 str.len = be16_to_cpu(dent->de_name_len);
994 str.hash = be32_to_cpu(dent->de_hash);
995 new = gfs2_dirent_alloc(inode, nbh, &str);
996 if (IS_ERR(new)) {
997 error = PTR_ERR(new);
998 break;
999 }
1000
1001 new->de_inum = dent->de_inum; /* No endian worries */
1002 new->de_type = dent->de_type; /* No endian worries */
1003 be16_add_cpu(&nleaf->lf_entries, 1);
1004
1005 dirent_del(dip, obh, prev, dent);
1006
1007 if (!oleaf->lf_entries)
1008 gfs2_consist_inode(dip);
1009 be16_add_cpu(&oleaf->lf_entries, -1);
1010
1011 if (!prev)
1012 prev = dent;
1013
1014 moved = 1;
1015 } else {
1016 prev = dent;
1017 }
1018 dent = next;
1019 } while (dent);
1020
1021 oleaf->lf_depth = nleaf->lf_depth;
1022
1023 error = gfs2_meta_inode_buffer(dip, &dibh);
1024 if (!gfs2_assert_withdraw(GFS2_SB(&dip->i_inode), !error)) {
1025 gfs2_trans_add_bh(dip->i_gl, dibh, 1);
1026 gfs2_add_inode_blocks(&dip->i_inode, 1);
1027 gfs2_dinode_out(dip, dibh->b_data);
1028 brelse(dibh);
1029 }
1030
1031 brelse(obh);
1032 brelse(nbh);
1033
1034 return error;
1035
1036 fail_lpfree:
1037 kfree(lp);
1038
1039 fail_brelse:
1040 brelse(obh);
1041 brelse(nbh);
1042 return error;
1043 }
1044
1045 /**
1046 * dir_double_exhash - Double size of ExHash table
1047 * @dip: The GFS2 dinode
1048 *
1049 * Returns: 0 on success, error code on failure
1050 */
1051
1052 static int dir_double_exhash(struct gfs2_inode *dip)
1053 {
1054 struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
1055 struct buffer_head *dibh;
1056 u32 hsize;
1057 u64 *buf;
1058 u64 *from, *to;
1059 u64 block;
1060 int x;
1061 int error = 0;
1062
1063 hsize = 1 << dip->i_depth;
1064 if (hsize * sizeof(u64) != dip->i_disksize) {
1065 gfs2_consist_inode(dip);
1066 return -EIO;
1067 }
1068
1069 /* Allocate both the "from" and "to" buffers in one big chunk */
1070
1071 buf = kcalloc(3, sdp->sd_hash_bsize, GFP_NOFS);
1072 if (!buf)
1073 return -ENOMEM;
1074
1075 for (block = dip->i_disksize >> sdp->sd_hash_bsize_shift; block--;) {
1076 error = gfs2_dir_read_data(dip, (char *)buf,
1077 block * sdp->sd_hash_bsize,
1078 sdp->sd_hash_bsize, 1);
1079 if (error != sdp->sd_hash_bsize) {
1080 if (error >= 0)
1081 error = -EIO;
1082 goto fail;
1083 }
1084
1085 from = buf;
1086 to = (u64 *)((char *)buf + sdp->sd_hash_bsize);
1087
1088 for (x = sdp->sd_hash_ptrs; x--; from++) {
1089 *to++ = *from; /* No endianess worries */
1090 *to++ = *from;
1091 }
1092
1093 error = gfs2_dir_write_data(dip,
1094 (char *)buf + sdp->sd_hash_bsize,
1095 block * sdp->sd_sb.sb_bsize,
1096 sdp->sd_sb.sb_bsize);
1097 if (error != sdp->sd_sb.sb_bsize) {
1098 if (error >= 0)
1099 error = -EIO;
1100 goto fail;
1101 }
1102 }
1103
1104 kfree(buf);
1105
1106 error = gfs2_meta_inode_buffer(dip, &dibh);
1107 if (!gfs2_assert_withdraw(sdp, !error)) {
1108 dip->i_depth++;
1109 gfs2_dinode_out(dip, dibh->b_data);
1110 brelse(dibh);
1111 }
1112
1113 return error;
1114
1115 fail:
1116 kfree(buf);
1117 return error;
1118 }
1119
1120 /**
1121 * compare_dents - compare directory entries by hash value
1122 * @a: first dent
1123 * @b: second dent
1124 *
1125 * When comparing the hash entries of @a to @b:
1126 * gt: returns 1
1127 * lt: returns -1
1128 * eq: returns 0
1129 */
1130
1131 static int compare_dents(const void *a, const void *b)
1132 {
1133 const struct gfs2_dirent *dent_a, *dent_b;
1134 u32 hash_a, hash_b;
1135 int ret = 0;
1136
1137 dent_a = *(const struct gfs2_dirent **)a;
1138 hash_a = be32_to_cpu(dent_a->de_hash);
1139
1140 dent_b = *(const struct gfs2_dirent **)b;
1141 hash_b = be32_to_cpu(dent_b->de_hash);
1142
1143 if (hash_a > hash_b)
1144 ret = 1;
1145 else if (hash_a < hash_b)
1146 ret = -1;
1147 else {
1148 unsigned int len_a = be16_to_cpu(dent_a->de_name_len);
1149 unsigned int len_b = be16_to_cpu(dent_b->de_name_len);
1150
1151 if (len_a > len_b)
1152 ret = 1;
1153 else if (len_a < len_b)
1154 ret = -1;
1155 else
1156 ret = memcmp(dent_a + 1, dent_b + 1, len_a);
1157 }
1158
1159 return ret;
1160 }
1161
1162 /**
1163 * do_filldir_main - read out directory entries
1164 * @dip: The GFS2 inode
1165 * @offset: The offset in the file to read from
1166 * @opaque: opaque data to pass to filldir
1167 * @filldir: The function to pass entries to
1168 * @darr: an array of struct gfs2_dirent pointers to read
1169 * @entries: the number of entries in darr
1170 * @copied: pointer to int that's non-zero if a entry has been copied out
1171 *
1172 * Jump through some hoops to make sure that if there are hash collsions,
1173 * they are read out at the beginning of a buffer. We want to minimize
1174 * the possibility that they will fall into different readdir buffers or
1175 * that someone will want to seek to that location.
1176 *
1177 * Returns: errno, >0 on exception from filldir
1178 */
1179
1180 static int do_filldir_main(struct gfs2_inode *dip, u64 *offset,
1181 void *opaque, filldir_t filldir,
1182 const struct gfs2_dirent **darr, u32 entries,
1183 int *copied)
1184 {
1185 const struct gfs2_dirent *dent, *dent_next;
1186 u64 off, off_next;
1187 unsigned int x, y;
1188 int run = 0;
1189 int error = 0;
1190
1191 sort(darr, entries, sizeof(struct gfs2_dirent *), compare_dents, NULL);
1192
1193 dent_next = darr[0];
1194 off_next = be32_to_cpu(dent_next->de_hash);
1195 off_next = gfs2_disk_hash2offset(off_next);
1196
1197 for (x = 0, y = 1; x < entries; x++, y++) {
1198 dent = dent_next;
1199 off = off_next;
1200
1201 if (y < entries) {
1202 dent_next = darr[y];
1203 off_next = be32_to_cpu(dent_next->de_hash);
1204 off_next = gfs2_disk_hash2offset(off_next);
1205
1206 if (off < *offset)
1207 continue;
1208 *offset = off;
1209
1210 if (off_next == off) {
1211 if (*copied && !run)
1212 return 1;
1213 run = 1;
1214 } else
1215 run = 0;
1216 } else {
1217 if (off < *offset)
1218 continue;
1219 *offset = off;
1220 }
1221
1222 error = filldir(opaque, (const char *)(dent + 1),
1223 be16_to_cpu(dent->de_name_len),
1224 off, be64_to_cpu(dent->de_inum.no_addr),
1225 be16_to_cpu(dent->de_type));
1226 if (error)
1227 return 1;
1228
1229 *copied = 1;
1230 }
1231
1232 /* Increment the *offset by one, so the next time we come into the
1233 do_filldir fxn, we get the next entry instead of the last one in the
1234 current leaf */
1235
1236 (*offset)++;
1237
1238 return 0;
1239 }
1240
1241 static void *gfs2_alloc_sort_buffer(unsigned size)
1242 {
1243 void *ptr = NULL;
1244
1245 if (size < KMALLOC_MAX_SIZE)
1246 ptr = kmalloc(size, GFP_NOFS | __GFP_NOWARN);
1247 if (!ptr)
1248 ptr = __vmalloc(size, GFP_NOFS, PAGE_KERNEL);
1249 return ptr;
1250 }
1251
1252 static void gfs2_free_sort_buffer(void *ptr)
1253 {
1254 if (is_vmalloc_addr(ptr))
1255 vfree(ptr);
1256 else
1257 kfree(ptr);
1258 }
1259
1260 static int gfs2_dir_read_leaf(struct inode *inode, u64 *offset, void *opaque,
1261 filldir_t filldir, int *copied, unsigned *depth,
1262 u64 leaf_no)
1263 {
1264 struct gfs2_inode *ip = GFS2_I(inode);
1265 struct gfs2_sbd *sdp = GFS2_SB(inode);
1266 struct buffer_head *bh;
1267 struct gfs2_leaf *lf;
1268 unsigned entries = 0, entries2 = 0;
1269 unsigned leaves = 0;
1270 const struct gfs2_dirent **darr, *dent;
1271 struct dirent_gather g;
1272 struct buffer_head **larr;
1273 int leaf = 0;
1274 int error, i;
1275 u64 lfn = leaf_no;
1276
1277 do {
1278 error = get_leaf(ip, lfn, &bh);
1279 if (error)
1280 goto out;
1281 lf = (struct gfs2_leaf *)bh->b_data;
1282 if (leaves == 0)
1283 *depth = be16_to_cpu(lf->lf_depth);
1284 entries += be16_to_cpu(lf->lf_entries);
1285 leaves++;
1286 lfn = be64_to_cpu(lf->lf_next);
1287 brelse(bh);
1288 } while(lfn);
1289
1290 if (!entries)
1291 return 0;
1292
1293 error = -ENOMEM;
1294 /*
1295 * The extra 99 entries are not normally used, but are a buffer
1296 * zone in case the number of entries in the leaf is corrupt.
1297 * 99 is the maximum number of entries that can fit in a single
1298 * leaf block.
1299 */
1300 larr = gfs2_alloc_sort_buffer((leaves + entries + 99) * sizeof(void *));
1301 if (!larr)
1302 goto out;
1303 darr = (const struct gfs2_dirent **)(larr + leaves);
1304 g.pdent = darr;
1305 g.offset = 0;
1306 lfn = leaf_no;
1307
1308 do {
1309 error = get_leaf(ip, lfn, &bh);
1310 if (error)
1311 goto out_free;
1312 lf = (struct gfs2_leaf *)bh->b_data;
1313 lfn = be64_to_cpu(lf->lf_next);
1314 if (lf->lf_entries) {
1315 entries2 += be16_to_cpu(lf->lf_entries);
1316 dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size,
1317 gfs2_dirent_gather, NULL, &g);
1318 error = PTR_ERR(dent);
1319 if (IS_ERR(dent))
1320 goto out_free;
1321 if (entries2 != g.offset) {
1322 fs_warn(sdp, "Number of entries corrupt in dir "
1323 "leaf %llu, entries2 (%u) != "
1324 "g.offset (%u)\n",
1325 (unsigned long long)bh->b_blocknr,
1326 entries2, g.offset);
1327
1328 error = -EIO;
1329 goto out_free;
1330 }
1331 error = 0;
1332 larr[leaf++] = bh;
1333 } else {
1334 brelse(bh);
1335 }
1336 } while(lfn);
1337
1338 BUG_ON(entries2 != entries);
1339 error = do_filldir_main(ip, offset, opaque, filldir, darr,
1340 entries, copied);
1341 out_free:
1342 for(i = 0; i < leaf; i++)
1343 brelse(larr[i]);
1344 gfs2_free_sort_buffer(larr);
1345 out:
1346 return error;
1347 }
1348
1349 /**
1350 * dir_e_read - Reads the entries from a directory into a filldir buffer
1351 * @dip: dinode pointer
1352 * @offset: the hash of the last entry read shifted to the right once
1353 * @opaque: buffer for the filldir function to fill
1354 * @filldir: points to the filldir function to use
1355 *
1356 * Returns: errno
1357 */
1358
1359 static int dir_e_read(struct inode *inode, u64 *offset, void *opaque,
1360 filldir_t filldir)
1361 {
1362 struct gfs2_inode *dip = GFS2_I(inode);
1363 struct gfs2_sbd *sdp = GFS2_SB(inode);
1364 u32 hsize, len = 0;
1365 u32 ht_offset, lp_offset, ht_offset_cur = -1;
1366 u32 hash, index;
1367 __be64 *lp;
1368 int copied = 0;
1369 int error = 0;
1370 unsigned depth = 0;
1371
1372 hsize = 1 << dip->i_depth;
1373 if (hsize * sizeof(u64) != dip->i_disksize) {
1374 gfs2_consist_inode(dip);
1375 return -EIO;
1376 }
1377
1378 hash = gfs2_dir_offset2hash(*offset);
1379 index = hash >> (32 - dip->i_depth);
1380
1381 lp = kmalloc(sdp->sd_hash_bsize, GFP_NOFS);
1382 if (!lp)
1383 return -ENOMEM;
1384
1385 while (index < hsize) {
1386 lp_offset = index & (sdp->sd_hash_ptrs - 1);
1387 ht_offset = index - lp_offset;
1388
1389 if (ht_offset_cur != ht_offset) {
1390 error = gfs2_dir_read_data(dip, (char *)lp,
1391 ht_offset * sizeof(__be64),
1392 sdp->sd_hash_bsize, 1);
1393 if (error != sdp->sd_hash_bsize) {
1394 if (error >= 0)
1395 error = -EIO;
1396 goto out;
1397 }
1398 ht_offset_cur = ht_offset;
1399 }
1400
1401 error = gfs2_dir_read_leaf(inode, offset, opaque, filldir,
1402 &copied, &depth,
1403 be64_to_cpu(lp[lp_offset]));
1404 if (error)
1405 break;
1406
1407 len = 1 << (dip->i_depth - depth);
1408 index = (index & ~(len - 1)) + len;
1409 }
1410
1411 out:
1412 kfree(lp);
1413 if (error > 0)
1414 error = 0;
1415 return error;
1416 }
1417
1418 int gfs2_dir_read(struct inode *inode, u64 *offset, void *opaque,
1419 filldir_t filldir)
1420 {
1421 struct gfs2_inode *dip = GFS2_I(inode);
1422 struct gfs2_sbd *sdp = GFS2_SB(inode);
1423 struct dirent_gather g;
1424 const struct gfs2_dirent **darr, *dent;
1425 struct buffer_head *dibh;
1426 int copied = 0;
1427 int error;
1428
1429 if (!dip->i_entries)
1430 return 0;
1431
1432 if (dip->i_diskflags & GFS2_DIF_EXHASH)
1433 return dir_e_read(inode, offset, opaque, filldir);
1434
1435 if (!gfs2_is_stuffed(dip)) {
1436 gfs2_consist_inode(dip);
1437 return -EIO;
1438 }
1439
1440 error = gfs2_meta_inode_buffer(dip, &dibh);
1441 if (error)
1442 return error;
1443
1444 error = -ENOMEM;
1445 /* 96 is max number of dirents which can be stuffed into an inode */
1446 darr = kmalloc(96 * sizeof(struct gfs2_dirent *), GFP_NOFS);
1447 if (darr) {
1448 g.pdent = darr;
1449 g.offset = 0;
1450 dent = gfs2_dirent_scan(inode, dibh->b_data, dibh->b_size,
1451 gfs2_dirent_gather, NULL, &g);
1452 if (IS_ERR(dent)) {
1453 error = PTR_ERR(dent);
1454 goto out;
1455 }
1456 if (dip->i_entries != g.offset) {
1457 fs_warn(sdp, "Number of entries corrupt in dir %llu, "
1458 "ip->i_entries (%u) != g.offset (%u)\n",
1459 (unsigned long long)dip->i_no_addr,
1460 dip->i_entries,
1461 g.offset);
1462 error = -EIO;
1463 goto out;
1464 }
1465 error = do_filldir_main(dip, offset, opaque, filldir, darr,
1466 dip->i_entries, &copied);
1467 out:
1468 kfree(darr);
1469 }
1470
1471 if (error > 0)
1472 error = 0;
1473
1474 brelse(dibh);
1475
1476 return error;
1477 }
1478
1479 /**
1480 * gfs2_dir_search - Search a directory
1481 * @dip: The GFS2 inode
1482 * @filename:
1483 * @inode:
1484 *
1485 * This routine searches a directory for a file or another directory.
1486 * Assumes a glock is held on dip.
1487 *
1488 * Returns: errno
1489 */
1490
1491 struct inode *gfs2_dir_search(struct inode *dir, const struct qstr *name)
1492 {
1493 struct buffer_head *bh;
1494 struct gfs2_dirent *dent;
1495 struct inode *inode;
1496
1497 dent = gfs2_dirent_search(dir, name, gfs2_dirent_find, &bh);
1498 if (dent) {
1499 if (IS_ERR(dent))
1500 return ERR_CAST(dent);
1501 inode = gfs2_inode_lookup(dir->i_sb,
1502 be16_to_cpu(dent->de_type),
1503 be64_to_cpu(dent->de_inum.no_addr),
1504 be64_to_cpu(dent->de_inum.no_formal_ino));
1505 brelse(bh);
1506 return inode;
1507 }
1508 return ERR_PTR(-ENOENT);
1509 }
1510
1511 int gfs2_dir_check(struct inode *dir, const struct qstr *name,
1512 const struct gfs2_inode *ip)
1513 {
1514 struct buffer_head *bh;
1515 struct gfs2_dirent *dent;
1516 int ret = -ENOENT;
1517
1518 dent = gfs2_dirent_search(dir, name, gfs2_dirent_find, &bh);
1519 if (dent) {
1520 if (IS_ERR(dent))
1521 return PTR_ERR(dent);
1522 if (ip) {
1523 if (be64_to_cpu(dent->de_inum.no_addr) != ip->i_no_addr)
1524 goto out;
1525 if (be64_to_cpu(dent->de_inum.no_formal_ino) !=
1526 ip->i_no_formal_ino)
1527 goto out;
1528 if (unlikely(IF2DT(ip->i_inode.i_mode) !=
1529 be16_to_cpu(dent->de_type))) {
1530 gfs2_consist_inode(GFS2_I(dir));
1531 ret = -EIO;
1532 goto out;
1533 }
1534 }
1535 ret = 0;
1536 out:
1537 brelse(bh);
1538 }
1539 return ret;
1540 }
1541
1542 static int dir_new_leaf(struct inode *inode, const struct qstr *name)
1543 {
1544 struct buffer_head *bh, *obh;
1545 struct gfs2_inode *ip = GFS2_I(inode);
1546 struct gfs2_leaf *leaf, *oleaf;
1547 int error;
1548 u32 index;
1549 u64 bn;
1550
1551 index = name->hash >> (32 - ip->i_depth);
1552 error = get_first_leaf(ip, index, &obh);
1553 if (error)
1554 return error;
1555 do {
1556 oleaf = (struct gfs2_leaf *)obh->b_data;
1557 bn = be64_to_cpu(oleaf->lf_next);
1558 if (!bn)
1559 break;
1560 brelse(obh);
1561 error = get_leaf(ip, bn, &obh);
1562 if (error)
1563 return error;
1564 } while(1);
1565
1566 gfs2_trans_add_bh(ip->i_gl, obh, 1);
1567
1568 leaf = new_leaf(inode, &bh, be16_to_cpu(oleaf->lf_depth));
1569 if (!leaf) {
1570 brelse(obh);
1571 return -ENOSPC;
1572 }
1573 oleaf->lf_next = cpu_to_be64(bh->b_blocknr);
1574 brelse(bh);
1575 brelse(obh);
1576
1577 error = gfs2_meta_inode_buffer(ip, &bh);
1578 if (error)
1579 return error;
1580 gfs2_trans_add_bh(ip->i_gl, bh, 1);
1581 gfs2_add_inode_blocks(&ip->i_inode, 1);
1582 gfs2_dinode_out(ip, bh->b_data);
1583 brelse(bh);
1584 return 0;
1585 }
1586
1587 /**
1588 * gfs2_dir_add - Add new filename into directory
1589 * @dip: The GFS2 inode
1590 * @filename: The new name
1591 * @inode: The inode number of the entry
1592 * @type: The type of the entry
1593 *
1594 * Returns: 0 on success, error code on failure
1595 */
1596
1597 int gfs2_dir_add(struct inode *inode, const struct qstr *name,
1598 const struct gfs2_inode *nip, unsigned type)
1599 {
1600 struct gfs2_inode *ip = GFS2_I(inode);
1601 struct buffer_head *bh;
1602 struct gfs2_dirent *dent;
1603 struct gfs2_leaf *leaf;
1604 int error;
1605
1606 while(1) {
1607 dent = gfs2_dirent_search(inode, name, gfs2_dirent_find_space,
1608 &bh);
1609 if (dent) {
1610 if (IS_ERR(dent))
1611 return PTR_ERR(dent);
1612 dent = gfs2_init_dirent(inode, dent, name, bh);
1613 gfs2_inum_out(nip, dent);
1614 dent->de_type = cpu_to_be16(type);
1615 if (ip->i_diskflags & GFS2_DIF_EXHASH) {
1616 leaf = (struct gfs2_leaf *)bh->b_data;
1617 be16_add_cpu(&leaf->lf_entries, 1);
1618 }
1619 brelse(bh);
1620 error = gfs2_meta_inode_buffer(ip, &bh);
1621 if (error)
1622 break;
1623 gfs2_trans_add_bh(ip->i_gl, bh, 1);
1624 ip->i_entries++;
1625 ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
1626 gfs2_dinode_out(ip, bh->b_data);
1627 brelse(bh);
1628 error = 0;
1629 break;
1630 }
1631 if (!(ip->i_diskflags & GFS2_DIF_EXHASH)) {
1632 error = dir_make_exhash(inode);
1633 if (error)
1634 break;
1635 continue;
1636 }
1637 error = dir_split_leaf(inode, name);
1638 if (error == 0)
1639 continue;
1640 if (error < 0)
1641 break;
1642 if (ip->i_depth < GFS2_DIR_MAX_DEPTH) {
1643 error = dir_double_exhash(ip);
1644 if (error)
1645 break;
1646 error = dir_split_leaf(inode, name);
1647 if (error < 0)
1648 break;
1649 if (error == 0)
1650 continue;
1651 }
1652 error = dir_new_leaf(inode, name);
1653 if (!error)
1654 continue;
1655 error = -ENOSPC;
1656 break;
1657 }
1658 return error;
1659 }
1660
1661
1662 /**
1663 * gfs2_dir_del - Delete a directory entry
1664 * @dip: The GFS2 inode
1665 * @filename: The filename
1666 *
1667 * Returns: 0 on success, error code on failure
1668 */
1669
1670 int gfs2_dir_del(struct gfs2_inode *dip, const struct qstr *name)
1671 {
1672 struct gfs2_dirent *dent, *prev = NULL;
1673 struct buffer_head *bh;
1674 int error;
1675
1676 /* Returns _either_ the entry (if its first in block) or the
1677 previous entry otherwise */
1678 dent = gfs2_dirent_search(&dip->i_inode, name, gfs2_dirent_prev, &bh);
1679 if (!dent) {
1680 gfs2_consist_inode(dip);
1681 return -EIO;
1682 }
1683 if (IS_ERR(dent)) {
1684 gfs2_consist_inode(dip);
1685 return PTR_ERR(dent);
1686 }
1687 /* If not first in block, adjust pointers accordingly */
1688 if (gfs2_dirent_find(dent, name, NULL) == 0) {
1689 prev = dent;
1690 dent = (struct gfs2_dirent *)((char *)dent + be16_to_cpu(prev->de_rec_len));
1691 }
1692
1693 dirent_del(dip, bh, prev, dent);
1694 if (dip->i_diskflags & GFS2_DIF_EXHASH) {
1695 struct gfs2_leaf *leaf = (struct gfs2_leaf *)bh->b_data;
1696 u16 entries = be16_to_cpu(leaf->lf_entries);
1697 if (!entries)
1698 gfs2_consist_inode(dip);
1699 leaf->lf_entries = cpu_to_be16(--entries);
1700 }
1701 brelse(bh);
1702
1703 error = gfs2_meta_inode_buffer(dip, &bh);
1704 if (error)
1705 return error;
1706
1707 if (!dip->i_entries)
1708 gfs2_consist_inode(dip);
1709 gfs2_trans_add_bh(dip->i_gl, bh, 1);
1710 dip->i_entries--;
1711 dip->i_inode.i_mtime = dip->i_inode.i_ctime = CURRENT_TIME;
1712 gfs2_dinode_out(dip, bh->b_data);
1713 brelse(bh);
1714 mark_inode_dirty(&dip->i_inode);
1715
1716 return error;
1717 }
1718
1719 /**
1720 * gfs2_dir_mvino - Change inode number of directory entry
1721 * @dip: The GFS2 inode
1722 * @filename:
1723 * @new_inode:
1724 *
1725 * This routine changes the inode number of a directory entry. It's used
1726 * by rename to change ".." when a directory is moved.
1727 * Assumes a glock is held on dvp.
1728 *
1729 * Returns: errno
1730 */
1731
1732 int gfs2_dir_mvino(struct gfs2_inode *dip, const struct qstr *filename,
1733 const struct gfs2_inode *nip, unsigned int new_type)
1734 {
1735 struct buffer_head *bh;
1736 struct gfs2_dirent *dent;
1737 int error;
1738
1739 dent = gfs2_dirent_search(&dip->i_inode, filename, gfs2_dirent_find, &bh);
1740 if (!dent) {
1741 gfs2_consist_inode(dip);
1742 return -EIO;
1743 }
1744 if (IS_ERR(dent))
1745 return PTR_ERR(dent);
1746
1747 gfs2_trans_add_bh(dip->i_gl, bh, 1);
1748 gfs2_inum_out(nip, dent);
1749 dent->de_type = cpu_to_be16(new_type);
1750
1751 if (dip->i_diskflags & GFS2_DIF_EXHASH) {
1752 brelse(bh);
1753 error = gfs2_meta_inode_buffer(dip, &bh);
1754 if (error)
1755 return error;
1756 gfs2_trans_add_bh(dip->i_gl, bh, 1);
1757 }
1758
1759 dip->i_inode.i_mtime = dip->i_inode.i_ctime = CURRENT_TIME;
1760 gfs2_dinode_out(dip, bh->b_data);
1761 brelse(bh);
1762 return 0;
1763 }
1764
1765 /**
1766 * foreach_leaf - call a function for each leaf in a directory
1767 * @dip: the directory
1768 * @lc: the function to call for each each
1769 * @data: private data to pass to it
1770 *
1771 * Returns: errno
1772 */
1773
1774 static int foreach_leaf(struct gfs2_inode *dip, leaf_call_t lc, void *data)
1775 {
1776 struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
1777 struct buffer_head *bh;
1778 struct gfs2_leaf *leaf;
1779 u32 hsize, len;
1780 u32 ht_offset, lp_offset, ht_offset_cur = -1;
1781 u32 index = 0;
1782 __be64 *lp;
1783 u64 leaf_no;
1784 int error = 0;
1785
1786 hsize = 1 << dip->i_depth;
1787 if (hsize * sizeof(u64) != dip->i_disksize) {
1788 gfs2_consist_inode(dip);
1789 return -EIO;
1790 }
1791
1792 lp = kmalloc(sdp->sd_hash_bsize, GFP_NOFS);
1793 if (!lp)
1794 return -ENOMEM;
1795
1796 while (index < hsize) {
1797 lp_offset = index & (sdp->sd_hash_ptrs - 1);
1798 ht_offset = index - lp_offset;
1799
1800 if (ht_offset_cur != ht_offset) {
1801 error = gfs2_dir_read_data(dip, (char *)lp,
1802 ht_offset * sizeof(__be64),
1803 sdp->sd_hash_bsize, 1);
1804 if (error != sdp->sd_hash_bsize) {
1805 if (error >= 0)
1806 error = -EIO;
1807 goto out;
1808 }
1809 ht_offset_cur = ht_offset;
1810 }
1811
1812 leaf_no = be64_to_cpu(lp[lp_offset]);
1813 if (leaf_no) {
1814 error = get_leaf(dip, leaf_no, &bh);
1815 if (error)
1816 goto out;
1817 leaf = (struct gfs2_leaf *)bh->b_data;
1818 len = 1 << (dip->i_depth - be16_to_cpu(leaf->lf_depth));
1819 brelse(bh);
1820
1821 error = lc(dip, index, len, leaf_no, data);
1822 if (error)
1823 goto out;
1824
1825 index = (index & ~(len - 1)) + len;
1826 } else
1827 index++;
1828 }
1829
1830 if (index != hsize) {
1831 gfs2_consist_inode(dip);
1832 error = -EIO;
1833 }
1834
1835 out:
1836 kfree(lp);
1837
1838 return error;
1839 }
1840
1841 /**
1842 * leaf_dealloc - Deallocate a directory leaf
1843 * @dip: the directory
1844 * @index: the hash table offset in the directory
1845 * @len: the number of pointers to this leaf
1846 * @leaf_no: the leaf number
1847 * @data: not used
1848 *
1849 * Returns: errno
1850 */
1851
1852 static int leaf_dealloc(struct gfs2_inode *dip, u32 index, u32 len,
1853 u64 leaf_no, void *data)
1854 {
1855 struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
1856 struct gfs2_leaf *tmp_leaf;
1857 struct gfs2_rgrp_list rlist;
1858 struct buffer_head *bh, *dibh;
1859 u64 blk, nblk;
1860 unsigned int rg_blocks = 0, l_blocks = 0;
1861 char *ht;
1862 unsigned int x, size = len * sizeof(u64);
1863 int error;
1864
1865 memset(&rlist, 0, sizeof(struct gfs2_rgrp_list));
1866
1867 ht = kzalloc(size, GFP_NOFS);
1868 if (!ht)
1869 return -ENOMEM;
1870
1871 if (!gfs2_alloc_get(dip)) {
1872 error = -ENOMEM;
1873 goto out;
1874 }
1875
1876 error = gfs2_quota_hold(dip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
1877 if (error)
1878 goto out_put;
1879
1880 error = gfs2_rindex_hold(sdp, &dip->i_alloc->al_ri_gh);
1881 if (error)
1882 goto out_qs;
1883
1884 /* Count the number of leaves */
1885
1886 for (blk = leaf_no; blk; blk = nblk) {
1887 error = get_leaf(dip, blk, &bh);
1888 if (error)
1889 goto out_rlist;
1890 tmp_leaf = (struct gfs2_leaf *)bh->b_data;
1891 nblk = be64_to_cpu(tmp_leaf->lf_next);
1892 brelse(bh);
1893
1894 gfs2_rlist_add(sdp, &rlist, blk);
1895 l_blocks++;
1896 }
1897
1898 gfs2_rlist_alloc(&rlist, LM_ST_EXCLUSIVE);
1899
1900 for (x = 0; x < rlist.rl_rgrps; x++) {
1901 struct gfs2_rgrpd *rgd;
1902 rgd = rlist.rl_ghs[x].gh_gl->gl_object;
1903 rg_blocks += rgd->rd_length;
1904 }
1905
1906 error = gfs2_glock_nq_m(rlist.rl_rgrps, rlist.rl_ghs);
1907 if (error)
1908 goto out_rlist;
1909
1910 error = gfs2_trans_begin(sdp,
1911 rg_blocks + (DIV_ROUND_UP(size, sdp->sd_jbsize) + 1) +
1912 RES_DINODE + RES_STATFS + RES_QUOTA, l_blocks);
1913 if (error)
1914 goto out_rg_gunlock;
1915
1916 for (blk = leaf_no; blk; blk = nblk) {
1917 error = get_leaf(dip, blk, &bh);
1918 if (error)
1919 goto out_end_trans;
1920 tmp_leaf = (struct gfs2_leaf *)bh->b_data;
1921 nblk = be64_to_cpu(tmp_leaf->lf_next);
1922 brelse(bh);
1923
1924 gfs2_free_meta(dip, blk, 1);
1925 gfs2_add_inode_blocks(&dip->i_inode, -1);
1926 }
1927
1928 error = gfs2_dir_write_data(dip, ht, index * sizeof(u64), size);
1929 if (error != size) {
1930 if (error >= 0)
1931 error = -EIO;
1932 goto out_end_trans;
1933 }
1934
1935 error = gfs2_meta_inode_buffer(dip, &dibh);
1936 if (error)
1937 goto out_end_trans;
1938
1939 gfs2_trans_add_bh(dip->i_gl, dibh, 1);
1940 gfs2_dinode_out(dip, dibh->b_data);
1941 brelse(dibh);
1942
1943 out_end_trans:
1944 gfs2_trans_end(sdp);
1945 out_rg_gunlock:
1946 gfs2_glock_dq_m(rlist.rl_rgrps, rlist.rl_ghs);
1947 out_rlist:
1948 gfs2_rlist_free(&rlist);
1949 gfs2_glock_dq_uninit(&dip->i_alloc->al_ri_gh);
1950 out_qs:
1951 gfs2_quota_unhold(dip);
1952 out_put:
1953 gfs2_alloc_put(dip);
1954 out:
1955 kfree(ht);
1956 return error;
1957 }
1958
1959 /**
1960 * gfs2_dir_exhash_dealloc - free all the leaf blocks in a directory
1961 * @dip: the directory
1962 *
1963 * Dealloc all on-disk directory leaves to FREEMETA state
1964 * Change on-disk inode type to "regular file"
1965 *
1966 * Returns: errno
1967 */
1968
1969 int gfs2_dir_exhash_dealloc(struct gfs2_inode *dip)
1970 {
1971 struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
1972 struct buffer_head *bh;
1973 int error;
1974
1975 /* Dealloc on-disk leaves to FREEMETA state */
1976 error = foreach_leaf(dip, leaf_dealloc, NULL);
1977 if (error)
1978 return error;
1979
1980 /* Make this a regular file in case we crash.
1981 (We don't want to free these blocks a second time.) */
1982
1983 error = gfs2_trans_begin(sdp, RES_DINODE, 0);
1984 if (error)
1985 return error;
1986
1987 error = gfs2_meta_inode_buffer(dip, &bh);
1988 if (!error) {
1989 gfs2_trans_add_bh(dip->i_gl, bh, 1);
1990 ((struct gfs2_dinode *)bh->b_data)->di_mode =
1991 cpu_to_be32(S_IFREG);
1992 brelse(bh);
1993 }
1994
1995 gfs2_trans_end(sdp);
1996
1997 return error;
1998 }
1999
2000 /**
2001 * gfs2_diradd_alloc_required - find if adding entry will require an allocation
2002 * @ip: the file being written to
2003 * @filname: the filename that's going to be added
2004 *
2005 * Returns: 1 if alloc required, 0 if not, -ve on error
2006 */
2007
2008 int gfs2_diradd_alloc_required(struct inode *inode, const struct qstr *name)
2009 {
2010 struct gfs2_dirent *dent;
2011 struct buffer_head *bh;
2012
2013 dent = gfs2_dirent_search(inode, name, gfs2_dirent_find_space, &bh);
2014 if (!dent) {
2015 return 1;
2016 }
2017 if (IS_ERR(dent))
2018 return PTR_ERR(dent);
2019 brelse(bh);
2020 return 0;
2021 }
Tomato firmware and modifications.