ALSA: seq: Fix missing NULL check at remove_events ioctl
[linux/fpc-iii.git] / fs / gfs2 / dir.c
blobb631c904346084b5fb7b7d96985e724e7b4173a3
1 /*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
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 */
11 * Implements Extendible Hashing as described in:
12 * "Extendible Hashing" by Fagin, et al in
13 * __ACM Trans. on Database Systems__, Sept 1979.
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.
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.
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
39 * dip->i_diskflags & GFS2_DIF_EXHASH is true
41 * Otherwise, the dirents are "linear", within a single stuffed dinode block.
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.
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.
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>
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"
76 #define IS_LEAF 1 /* Hashed (leaf) directory */
77 #define IS_DINODE 2 /* Linear (stuffed dinode block) directory */
79 #define MAX_RA_BLOCKS 32 /* max read-ahead blocks */
81 #define gfs2_disk_hash2offset(h) (((u64)(h)) >> 1)
82 #define gfs2_dir_offset2hash(p) ((u32)(((u64)(p)) << 1))
84 struct qstr gfs2_qdot __read_mostly;
85 struct qstr gfs2_qdotdot __read_mostly;
87 typedef int (*gfs2_dscan_t)(const struct gfs2_dirent *dent,
88 const struct qstr *name, void *opaque);
90 int gfs2_dir_get_new_buffer(struct gfs2_inode *ip, u64 block,
91 struct buffer_head **bhp)
93 struct buffer_head *bh;
95 bh = gfs2_meta_new(ip->i_gl, block);
96 gfs2_trans_add_meta(ip->i_gl, bh);
97 gfs2_metatype_set(bh, GFS2_METATYPE_JD, GFS2_FORMAT_JD);
98 gfs2_buffer_clear_tail(bh, sizeof(struct gfs2_meta_header));
99 *bhp = bh;
100 return 0;
103 static int gfs2_dir_get_existing_buffer(struct gfs2_inode *ip, u64 block,
104 struct buffer_head **bhp)
106 struct buffer_head *bh;
107 int error;
109 error = gfs2_meta_read(ip->i_gl, block, DIO_WAIT, &bh);
110 if (error)
111 return error;
112 if (gfs2_metatype_check(GFS2_SB(&ip->i_inode), bh, GFS2_METATYPE_JD)) {
113 brelse(bh);
114 return -EIO;
116 *bhp = bh;
117 return 0;
120 static int gfs2_dir_write_stuffed(struct gfs2_inode *ip, const char *buf,
121 unsigned int offset, unsigned int size)
123 struct buffer_head *dibh;
124 int error;
126 error = gfs2_meta_inode_buffer(ip, &dibh);
127 if (error)
128 return error;
130 gfs2_trans_add_meta(ip->i_gl, dibh);
131 memcpy(dibh->b_data + offset + sizeof(struct gfs2_dinode), buf, size);
132 if (ip->i_inode.i_size < offset + size)
133 i_size_write(&ip->i_inode, offset + size);
134 ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
135 gfs2_dinode_out(ip, dibh->b_data);
137 brelse(dibh);
139 return size;
145 * gfs2_dir_write_data - Write directory information to the inode
146 * @ip: The GFS2 inode
147 * @buf: The buffer containing information to be written
148 * @offset: The file offset to start writing at
149 * @size: The amount of data to write
151 * Returns: The number of bytes correctly written or error code
153 static int gfs2_dir_write_data(struct gfs2_inode *ip, const char *buf,
154 u64 offset, unsigned int size)
156 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
157 struct buffer_head *dibh;
158 u64 lblock, dblock;
159 u32 extlen = 0;
160 unsigned int o;
161 int copied = 0;
162 int error = 0;
163 int new = 0;
165 if (!size)
166 return 0;
168 if (gfs2_is_stuffed(ip) &&
169 offset + size <= sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode))
170 return gfs2_dir_write_stuffed(ip, buf, (unsigned int)offset,
171 size);
173 if (gfs2_assert_warn(sdp, gfs2_is_jdata(ip)))
174 return -EINVAL;
176 if (gfs2_is_stuffed(ip)) {
177 error = gfs2_unstuff_dinode(ip, NULL);
178 if (error)
179 return error;
182 lblock = offset;
183 o = do_div(lblock, sdp->sd_jbsize) + sizeof(struct gfs2_meta_header);
185 while (copied < size) {
186 unsigned int amount;
187 struct buffer_head *bh;
189 amount = size - copied;
190 if (amount > sdp->sd_sb.sb_bsize - o)
191 amount = sdp->sd_sb.sb_bsize - o;
193 if (!extlen) {
194 new = 1;
195 error = gfs2_extent_map(&ip->i_inode, lblock, &new,
196 &dblock, &extlen);
197 if (error)
198 goto fail;
199 error = -EIO;
200 if (gfs2_assert_withdraw(sdp, dblock))
201 goto fail;
204 if (amount == sdp->sd_jbsize || new)
205 error = gfs2_dir_get_new_buffer(ip, dblock, &bh);
206 else
207 error = gfs2_dir_get_existing_buffer(ip, dblock, &bh);
209 if (error)
210 goto fail;
212 gfs2_trans_add_meta(ip->i_gl, bh);
213 memcpy(bh->b_data + o, buf, amount);
214 brelse(bh);
216 buf += amount;
217 copied += amount;
218 lblock++;
219 dblock++;
220 extlen--;
222 o = sizeof(struct gfs2_meta_header);
225 out:
226 error = gfs2_meta_inode_buffer(ip, &dibh);
227 if (error)
228 return error;
230 if (ip->i_inode.i_size < offset + copied)
231 i_size_write(&ip->i_inode, offset + copied);
232 ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
234 gfs2_trans_add_meta(ip->i_gl, dibh);
235 gfs2_dinode_out(ip, dibh->b_data);
236 brelse(dibh);
238 return copied;
239 fail:
240 if (copied)
241 goto out;
242 return error;
245 static int gfs2_dir_read_stuffed(struct gfs2_inode *ip, __be64 *buf,
246 unsigned int size)
248 struct buffer_head *dibh;
249 int error;
251 error = gfs2_meta_inode_buffer(ip, &dibh);
252 if (!error) {
253 memcpy(buf, dibh->b_data + sizeof(struct gfs2_dinode), size);
254 brelse(dibh);
257 return (error) ? error : size;
262 * gfs2_dir_read_data - Read a data from a directory inode
263 * @ip: The GFS2 Inode
264 * @buf: The buffer to place result into
265 * @size: Amount of data to transfer
267 * Returns: The amount of data actually copied or the error
269 static int gfs2_dir_read_data(struct gfs2_inode *ip, __be64 *buf,
270 unsigned int size)
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;
279 if (gfs2_is_stuffed(ip))
280 return gfs2_dir_read_stuffed(ip, buf, size);
282 if (gfs2_assert_warn(sdp, gfs2_is_jdata(ip)))
283 return -EINVAL;
285 lblock = 0;
286 o = do_div(lblock, sdp->sd_jbsize) + sizeof(struct gfs2_meta_header);
288 while (copied < size) {
289 unsigned int amount;
290 struct buffer_head *bh;
291 int new;
293 amount = size - copied;
294 if (amount > sdp->sd_sb.sb_bsize - o)
295 amount = sdp->sd_sb.sb_bsize - o;
297 if (!extlen) {
298 new = 0;
299 error = gfs2_extent_map(&ip->i_inode, lblock, &new,
300 &dblock, &extlen);
301 if (error || !dblock)
302 goto fail;
303 BUG_ON(extlen < 1);
304 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
305 } else {
306 error = gfs2_meta_read(ip->i_gl, dblock, DIO_WAIT, &bh);
307 if (error)
308 goto fail;
310 error = gfs2_metatype_check(sdp, bh, GFS2_METATYPE_JD);
311 if (error) {
312 brelse(bh);
313 goto fail;
315 dblock++;
316 extlen--;
317 memcpy(buf, bh->b_data + o, amount);
318 brelse(bh);
319 buf += (amount/sizeof(__be64));
320 copied += amount;
321 lblock++;
322 o = sizeof(struct gfs2_meta_header);
325 return copied;
326 fail:
327 return (copied) ? copied : error;
331 * gfs2_dir_get_hash_table - Get pointer to the dir hash table
332 * @ip: The inode in question
334 * Returns: The hash table or an error
337 static __be64 *gfs2_dir_get_hash_table(struct gfs2_inode *ip)
339 struct inode *inode = &ip->i_inode;
340 int ret;
341 u32 hsize;
342 __be64 *hc;
344 BUG_ON(!(ip->i_diskflags & GFS2_DIF_EXHASH));
346 hc = ip->i_hash_cache;
347 if (hc)
348 return hc;
350 hsize = 1 << ip->i_depth;
351 hsize *= sizeof(__be64);
352 if (hsize != i_size_read(&ip->i_inode)) {
353 gfs2_consist_inode(ip);
354 return ERR_PTR(-EIO);
357 hc = kmalloc(hsize, GFP_NOFS | __GFP_NOWARN);
358 if (hc == NULL)
359 hc = __vmalloc(hsize, GFP_NOFS, PAGE_KERNEL);
361 if (hc == NULL)
362 return ERR_PTR(-ENOMEM);
364 ret = gfs2_dir_read_data(ip, hc, hsize);
365 if (ret < 0) {
366 if (is_vmalloc_addr(hc))
367 vfree(hc);
368 else
369 kfree(hc);
370 return ERR_PTR(ret);
373 spin_lock(&inode->i_lock);
374 if (ip->i_hash_cache) {
375 if (is_vmalloc_addr(hc))
376 vfree(hc);
377 else
378 kfree(hc);
379 } else {
380 ip->i_hash_cache = hc;
382 spin_unlock(&inode->i_lock);
384 return ip->i_hash_cache;
388 * gfs2_dir_hash_inval - Invalidate dir hash
389 * @ip: The directory inode
391 * Must be called with an exclusive glock, or during glock invalidation.
393 void gfs2_dir_hash_inval(struct gfs2_inode *ip)
395 __be64 *hc = ip->i_hash_cache;
396 ip->i_hash_cache = NULL;
397 if (is_vmalloc_addr(hc))
398 vfree(hc);
399 else
400 kfree(hc);
403 static inline int gfs2_dirent_sentinel(const struct gfs2_dirent *dent)
405 return dent->de_inum.no_addr == 0 || dent->de_inum.no_formal_ino == 0;
408 static inline int __gfs2_dirent_find(const struct gfs2_dirent *dent,
409 const struct qstr *name, int ret)
411 if (!gfs2_dirent_sentinel(dent) &&
412 be32_to_cpu(dent->de_hash) == name->hash &&
413 be16_to_cpu(dent->de_name_len) == name->len &&
414 memcmp(dent+1, name->name, name->len) == 0)
415 return ret;
416 return 0;
419 static int gfs2_dirent_find(const struct gfs2_dirent *dent,
420 const struct qstr *name,
421 void *opaque)
423 return __gfs2_dirent_find(dent, name, 1);
426 static int gfs2_dirent_prev(const struct gfs2_dirent *dent,
427 const struct qstr *name,
428 void *opaque)
430 return __gfs2_dirent_find(dent, name, 2);
434 * name->name holds ptr to start of block.
435 * name->len holds size of block.
437 static int gfs2_dirent_last(const struct gfs2_dirent *dent,
438 const struct qstr *name,
439 void *opaque)
441 const char *start = name->name;
442 const char *end = (const char *)dent + be16_to_cpu(dent->de_rec_len);
443 if (name->len == (end - start))
444 return 1;
445 return 0;
448 static int gfs2_dirent_find_space(const struct gfs2_dirent *dent,
449 const struct qstr *name,
450 void *opaque)
452 unsigned required = GFS2_DIRENT_SIZE(name->len);
453 unsigned actual = GFS2_DIRENT_SIZE(be16_to_cpu(dent->de_name_len));
454 unsigned totlen = be16_to_cpu(dent->de_rec_len);
456 if (gfs2_dirent_sentinel(dent))
457 actual = 0;
458 if (totlen - actual >= required)
459 return 1;
460 return 0;
463 struct dirent_gather {
464 const struct gfs2_dirent **pdent;
465 unsigned offset;
468 static int gfs2_dirent_gather(const struct gfs2_dirent *dent,
469 const struct qstr *name,
470 void *opaque)
472 struct dirent_gather *g = opaque;
473 if (!gfs2_dirent_sentinel(dent)) {
474 g->pdent[g->offset++] = dent;
476 return 0;
480 * Other possible things to check:
481 * - Inode located within filesystem size (and on valid block)
482 * - Valid directory entry type
483 * Not sure how heavy-weight we want to make this... could also check
484 * hash is correct for example, but that would take a lot of extra time.
485 * For now the most important thing is to check that the various sizes
486 * are correct.
488 static int gfs2_check_dirent(struct gfs2_dirent *dent, unsigned int offset,
489 unsigned int size, unsigned int len, int first)
491 const char *msg = "gfs2_dirent too small";
492 if (unlikely(size < sizeof(struct gfs2_dirent)))
493 goto error;
494 msg = "gfs2_dirent misaligned";
495 if (unlikely(offset & 0x7))
496 goto error;
497 msg = "gfs2_dirent points beyond end of block";
498 if (unlikely(offset + size > len))
499 goto error;
500 msg = "zero inode number";
501 if (unlikely(!first && gfs2_dirent_sentinel(dent)))
502 goto error;
503 msg = "name length is greater than space in dirent";
504 if (!gfs2_dirent_sentinel(dent) &&
505 unlikely(sizeof(struct gfs2_dirent)+be16_to_cpu(dent->de_name_len) >
506 size))
507 goto error;
508 return 0;
509 error:
510 printk(KERN_WARNING "gfs2_check_dirent: %s (%s)\n", msg,
511 first ? "first in block" : "not first in block");
512 return -EIO;
515 static int gfs2_dirent_offset(const void *buf)
517 const struct gfs2_meta_header *h = buf;
518 int offset;
520 BUG_ON(buf == NULL);
522 switch(be32_to_cpu(h->mh_type)) {
523 case GFS2_METATYPE_LF:
524 offset = sizeof(struct gfs2_leaf);
525 break;
526 case GFS2_METATYPE_DI:
527 offset = sizeof(struct gfs2_dinode);
528 break;
529 default:
530 goto wrong_type;
532 return offset;
533 wrong_type:
534 printk(KERN_WARNING "gfs2_scan_dirent: wrong block type %u\n",
535 be32_to_cpu(h->mh_type));
536 return -1;
539 static struct gfs2_dirent *gfs2_dirent_scan(struct inode *inode, void *buf,
540 unsigned int len, gfs2_dscan_t scan,
541 const struct qstr *name,
542 void *opaque)
544 struct gfs2_dirent *dent, *prev;
545 unsigned offset;
546 unsigned size;
547 int ret = 0;
549 ret = gfs2_dirent_offset(buf);
550 if (ret < 0)
551 goto consist_inode;
553 offset = ret;
554 prev = NULL;
555 dent = buf + offset;
556 size = be16_to_cpu(dent->de_rec_len);
557 if (gfs2_check_dirent(dent, offset, size, len, 1))
558 goto consist_inode;
559 do {
560 ret = scan(dent, name, opaque);
561 if (ret)
562 break;
563 offset += size;
564 if (offset == len)
565 break;
566 prev = dent;
567 dent = buf + offset;
568 size = be16_to_cpu(dent->de_rec_len);
569 if (gfs2_check_dirent(dent, offset, size, len, 0))
570 goto consist_inode;
571 } while(1);
573 switch(ret) {
574 case 0:
575 return NULL;
576 case 1:
577 return dent;
578 case 2:
579 return prev ? prev : dent;
580 default:
581 BUG_ON(ret > 0);
582 return ERR_PTR(ret);
585 consist_inode:
586 gfs2_consist_inode(GFS2_I(inode));
587 return ERR_PTR(-EIO);
590 static int dirent_check_reclen(struct gfs2_inode *dip,
591 const struct gfs2_dirent *d, const void *end_p)
593 const void *ptr = d;
594 u16 rec_len = be16_to_cpu(d->de_rec_len);
596 if (unlikely(rec_len < sizeof(struct gfs2_dirent)))
597 goto broken;
598 ptr += rec_len;
599 if (ptr < end_p)
600 return rec_len;
601 if (ptr == end_p)
602 return -ENOENT;
603 broken:
604 gfs2_consist_inode(dip);
605 return -EIO;
609 * dirent_next - Next dirent
610 * @dip: the directory
611 * @bh: The buffer
612 * @dent: Pointer to list of dirents
614 * Returns: 0 on success, error code otherwise
617 static int dirent_next(struct gfs2_inode *dip, struct buffer_head *bh,
618 struct gfs2_dirent **dent)
620 struct gfs2_dirent *cur = *dent, *tmp;
621 char *bh_end = bh->b_data + bh->b_size;
622 int ret;
624 ret = dirent_check_reclen(dip, cur, bh_end);
625 if (ret < 0)
626 return ret;
628 tmp = (void *)cur + ret;
629 ret = dirent_check_reclen(dip, tmp, bh_end);
630 if (ret == -EIO)
631 return ret;
633 /* Only the first dent could ever have de_inum.no_addr == 0 */
634 if (gfs2_dirent_sentinel(tmp)) {
635 gfs2_consist_inode(dip);
636 return -EIO;
639 *dent = tmp;
640 return 0;
644 * dirent_del - Delete a dirent
645 * @dip: The GFS2 inode
646 * @bh: The buffer
647 * @prev: The previous dirent
648 * @cur: The current dirent
652 static void dirent_del(struct gfs2_inode *dip, struct buffer_head *bh,
653 struct gfs2_dirent *prev, struct gfs2_dirent *cur)
655 u16 cur_rec_len, prev_rec_len;
657 if (gfs2_dirent_sentinel(cur)) {
658 gfs2_consist_inode(dip);
659 return;
662 gfs2_trans_add_meta(dip->i_gl, bh);
664 /* If there is no prev entry, this is the first entry in the block.
665 The de_rec_len is already as big as it needs to be. Just zero
666 out the inode number and return. */
668 if (!prev) {
669 cur->de_inum.no_addr = 0;
670 cur->de_inum.no_formal_ino = 0;
671 return;
674 /* Combine this dentry with the previous one. */
676 prev_rec_len = be16_to_cpu(prev->de_rec_len);
677 cur_rec_len = be16_to_cpu(cur->de_rec_len);
679 if ((char *)prev + prev_rec_len != (char *)cur)
680 gfs2_consist_inode(dip);
681 if ((char *)cur + cur_rec_len > bh->b_data + bh->b_size)
682 gfs2_consist_inode(dip);
684 prev_rec_len += cur_rec_len;
685 prev->de_rec_len = cpu_to_be16(prev_rec_len);
689 * Takes a dent from which to grab space as an argument. Returns the
690 * newly created dent.
692 static struct gfs2_dirent *gfs2_init_dirent(struct inode *inode,
693 struct gfs2_dirent *dent,
694 const struct qstr *name,
695 struct buffer_head *bh)
697 struct gfs2_inode *ip = GFS2_I(inode);
698 struct gfs2_dirent *ndent;
699 unsigned offset = 0, totlen;
701 if (!gfs2_dirent_sentinel(dent))
702 offset = GFS2_DIRENT_SIZE(be16_to_cpu(dent->de_name_len));
703 totlen = be16_to_cpu(dent->de_rec_len);
704 BUG_ON(offset + name->len > totlen);
705 gfs2_trans_add_meta(ip->i_gl, bh);
706 ndent = (struct gfs2_dirent *)((char *)dent + offset);
707 dent->de_rec_len = cpu_to_be16(offset);
708 gfs2_qstr2dirent(name, totlen - offset, ndent);
709 return ndent;
712 static struct gfs2_dirent *gfs2_dirent_alloc(struct inode *inode,
713 struct buffer_head *bh,
714 const struct qstr *name)
716 struct gfs2_dirent *dent;
717 dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size,
718 gfs2_dirent_find_space, name, NULL);
719 if (!dent || IS_ERR(dent))
720 return dent;
721 return gfs2_init_dirent(inode, dent, name, bh);
724 static int get_leaf(struct gfs2_inode *dip, u64 leaf_no,
725 struct buffer_head **bhp)
727 int error;
729 error = gfs2_meta_read(dip->i_gl, leaf_no, DIO_WAIT, bhp);
730 if (!error && gfs2_metatype_check(GFS2_SB(&dip->i_inode), *bhp, GFS2_METATYPE_LF)) {
731 /* printk(KERN_INFO "block num=%llu\n", leaf_no); */
732 error = -EIO;
735 return error;
739 * get_leaf_nr - Get a leaf number associated with the index
740 * @dip: The GFS2 inode
741 * @index:
742 * @leaf_out:
744 * Returns: 0 on success, error code otherwise
747 static int get_leaf_nr(struct gfs2_inode *dip, u32 index,
748 u64 *leaf_out)
750 __be64 *hash;
752 hash = gfs2_dir_get_hash_table(dip);
753 if (IS_ERR(hash))
754 return PTR_ERR(hash);
755 *leaf_out = be64_to_cpu(*(hash + index));
756 return 0;
759 static int get_first_leaf(struct gfs2_inode *dip, u32 index,
760 struct buffer_head **bh_out)
762 u64 leaf_no;
763 int error;
765 error = get_leaf_nr(dip, index, &leaf_no);
766 if (!error)
767 error = get_leaf(dip, leaf_no, bh_out);
769 return error;
772 static struct gfs2_dirent *gfs2_dirent_search(struct inode *inode,
773 const struct qstr *name,
774 gfs2_dscan_t scan,
775 struct buffer_head **pbh)
777 struct buffer_head *bh;
778 struct gfs2_dirent *dent;
779 struct gfs2_inode *ip = GFS2_I(inode);
780 int error;
782 if (ip->i_diskflags & GFS2_DIF_EXHASH) {
783 struct gfs2_leaf *leaf;
784 unsigned hsize = 1 << ip->i_depth;
785 unsigned index;
786 u64 ln;
787 if (hsize * sizeof(u64) != i_size_read(inode)) {
788 gfs2_consist_inode(ip);
789 return ERR_PTR(-EIO);
792 index = name->hash >> (32 - ip->i_depth);
793 error = get_first_leaf(ip, index, &bh);
794 if (error)
795 return ERR_PTR(error);
796 do {
797 dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size,
798 scan, name, NULL);
799 if (dent)
800 goto got_dent;
801 leaf = (struct gfs2_leaf *)bh->b_data;
802 ln = be64_to_cpu(leaf->lf_next);
803 brelse(bh);
804 if (!ln)
805 break;
807 error = get_leaf(ip, ln, &bh);
808 } while(!error);
810 return error ? ERR_PTR(error) : NULL;
814 error = gfs2_meta_inode_buffer(ip, &bh);
815 if (error)
816 return ERR_PTR(error);
817 dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size, scan, name, NULL);
818 got_dent:
819 if (unlikely(dent == NULL || IS_ERR(dent))) {
820 brelse(bh);
821 bh = NULL;
823 *pbh = bh;
824 return dent;
827 static struct gfs2_leaf *new_leaf(struct inode *inode, struct buffer_head **pbh, u16 depth)
829 struct gfs2_inode *ip = GFS2_I(inode);
830 unsigned int n = 1;
831 u64 bn;
832 int error;
833 struct buffer_head *bh;
834 struct gfs2_leaf *leaf;
835 struct gfs2_dirent *dent;
836 struct qstr name = { .name = "" };
838 error = gfs2_alloc_blocks(ip, &bn, &n, 0, NULL);
839 if (error)
840 return NULL;
841 bh = gfs2_meta_new(ip->i_gl, bn);
842 if (!bh)
843 return NULL;
845 gfs2_trans_add_unrevoke(GFS2_SB(inode), bn, 1);
846 gfs2_trans_add_meta(ip->i_gl, bh);
847 gfs2_metatype_set(bh, GFS2_METATYPE_LF, GFS2_FORMAT_LF);
848 leaf = (struct gfs2_leaf *)bh->b_data;
849 leaf->lf_depth = cpu_to_be16(depth);
850 leaf->lf_entries = 0;
851 leaf->lf_dirent_format = cpu_to_be32(GFS2_FORMAT_DE);
852 leaf->lf_next = 0;
853 memset(leaf->lf_reserved, 0, sizeof(leaf->lf_reserved));
854 dent = (struct gfs2_dirent *)(leaf+1);
855 gfs2_qstr2dirent(&name, bh->b_size - sizeof(struct gfs2_leaf), dent);
856 *pbh = bh;
857 return leaf;
861 * dir_make_exhash - Convert a stuffed directory into an ExHash directory
862 * @dip: The GFS2 inode
864 * Returns: 0 on success, error code otherwise
867 static int dir_make_exhash(struct inode *inode)
869 struct gfs2_inode *dip = GFS2_I(inode);
870 struct gfs2_sbd *sdp = GFS2_SB(inode);
871 struct gfs2_dirent *dent;
872 struct qstr args;
873 struct buffer_head *bh, *dibh;
874 struct gfs2_leaf *leaf;
875 int y;
876 u32 x;
877 __be64 *lp;
878 u64 bn;
879 int error;
881 error = gfs2_meta_inode_buffer(dip, &dibh);
882 if (error)
883 return error;
885 /* Turn over a new leaf */
887 leaf = new_leaf(inode, &bh, 0);
888 if (!leaf)
889 return -ENOSPC;
890 bn = bh->b_blocknr;
892 gfs2_assert(sdp, dip->i_entries < (1 << 16));
893 leaf->lf_entries = cpu_to_be16(dip->i_entries);
895 /* Copy dirents */
897 gfs2_buffer_copy_tail(bh, sizeof(struct gfs2_leaf), dibh,
898 sizeof(struct gfs2_dinode));
900 /* Find last entry */
902 x = 0;
903 args.len = bh->b_size - sizeof(struct gfs2_dinode) +
904 sizeof(struct gfs2_leaf);
905 args.name = bh->b_data;
906 dent = gfs2_dirent_scan(&dip->i_inode, bh->b_data, bh->b_size,
907 gfs2_dirent_last, &args, NULL);
908 if (!dent) {
909 brelse(bh);
910 brelse(dibh);
911 return -EIO;
913 if (IS_ERR(dent)) {
914 brelse(bh);
915 brelse(dibh);
916 return PTR_ERR(dent);
919 /* Adjust the last dirent's record length
920 (Remember that dent still points to the last entry.) */
922 dent->de_rec_len = cpu_to_be16(be16_to_cpu(dent->de_rec_len) +
923 sizeof(struct gfs2_dinode) -
924 sizeof(struct gfs2_leaf));
926 brelse(bh);
928 /* We're done with the new leaf block, now setup the new
929 hash table. */
931 gfs2_trans_add_meta(dip->i_gl, dibh);
932 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
934 lp = (__be64 *)(dibh->b_data + sizeof(struct gfs2_dinode));
936 for (x = sdp->sd_hash_ptrs; x--; lp++)
937 *lp = cpu_to_be64(bn);
939 i_size_write(inode, sdp->sd_sb.sb_bsize / 2);
940 gfs2_add_inode_blocks(&dip->i_inode, 1);
941 dip->i_diskflags |= GFS2_DIF_EXHASH;
943 for (x = sdp->sd_hash_ptrs, y = -1; x; x >>= 1, y++) ;
944 dip->i_depth = y;
946 gfs2_dinode_out(dip, dibh->b_data);
948 brelse(dibh);
950 return 0;
954 * dir_split_leaf - Split a leaf block into two
955 * @dip: The GFS2 inode
956 * @index:
957 * @leaf_no:
959 * Returns: 0 on success, error code on failure
962 static int dir_split_leaf(struct inode *inode, const struct qstr *name)
964 struct gfs2_inode *dip = GFS2_I(inode);
965 struct buffer_head *nbh, *obh, *dibh;
966 struct gfs2_leaf *nleaf, *oleaf;
967 struct gfs2_dirent *dent = NULL, *prev = NULL, *next = NULL, *new;
968 u32 start, len, half_len, divider;
969 u64 bn, leaf_no;
970 __be64 *lp;
971 u32 index;
972 int x, moved = 0;
973 int error;
975 index = name->hash >> (32 - dip->i_depth);
976 error = get_leaf_nr(dip, index, &leaf_no);
977 if (error)
978 return error;
980 /* Get the old leaf block */
981 error = get_leaf(dip, leaf_no, &obh);
982 if (error)
983 return error;
985 oleaf = (struct gfs2_leaf *)obh->b_data;
986 if (dip->i_depth == be16_to_cpu(oleaf->lf_depth)) {
987 brelse(obh);
988 return 1; /* can't split */
991 gfs2_trans_add_meta(dip->i_gl, obh);
993 nleaf = new_leaf(inode, &nbh, be16_to_cpu(oleaf->lf_depth) + 1);
994 if (!nleaf) {
995 brelse(obh);
996 return -ENOSPC;
998 bn = nbh->b_blocknr;
1000 /* Compute the start and len of leaf pointers in the hash table. */
1001 len = 1 << (dip->i_depth - be16_to_cpu(oleaf->lf_depth));
1002 half_len = len >> 1;
1003 if (!half_len) {
1004 printk(KERN_WARNING "i_depth %u lf_depth %u index %u\n", dip->i_depth, be16_to_cpu(oleaf->lf_depth), index);
1005 gfs2_consist_inode(dip);
1006 error = -EIO;
1007 goto fail_brelse;
1010 start = (index & ~(len - 1));
1012 /* Change the pointers.
1013 Don't bother distinguishing stuffed from non-stuffed.
1014 This code is complicated enough already. */
1015 lp = kmalloc(half_len * sizeof(__be64), GFP_NOFS);
1016 if (!lp) {
1017 error = -ENOMEM;
1018 goto fail_brelse;
1021 /* Change the pointers */
1022 for (x = 0; x < half_len; x++)
1023 lp[x] = cpu_to_be64(bn);
1025 gfs2_dir_hash_inval(dip);
1027 error = gfs2_dir_write_data(dip, (char *)lp, start * sizeof(u64),
1028 half_len * sizeof(u64));
1029 if (error != half_len * sizeof(u64)) {
1030 if (error >= 0)
1031 error = -EIO;
1032 goto fail_lpfree;
1035 kfree(lp);
1037 /* Compute the divider */
1038 divider = (start + half_len) << (32 - dip->i_depth);
1040 /* Copy the entries */
1041 dent = (struct gfs2_dirent *)(obh->b_data + sizeof(struct gfs2_leaf));
1043 do {
1044 next = dent;
1045 if (dirent_next(dip, obh, &next))
1046 next = NULL;
1048 if (!gfs2_dirent_sentinel(dent) &&
1049 be32_to_cpu(dent->de_hash) < divider) {
1050 struct qstr str;
1051 str.name = (char*)(dent+1);
1052 str.len = be16_to_cpu(dent->de_name_len);
1053 str.hash = be32_to_cpu(dent->de_hash);
1054 new = gfs2_dirent_alloc(inode, nbh, &str);
1055 if (IS_ERR(new)) {
1056 error = PTR_ERR(new);
1057 break;
1060 new->de_inum = dent->de_inum; /* No endian worries */
1061 new->de_type = dent->de_type; /* No endian worries */
1062 be16_add_cpu(&nleaf->lf_entries, 1);
1064 dirent_del(dip, obh, prev, dent);
1066 if (!oleaf->lf_entries)
1067 gfs2_consist_inode(dip);
1068 be16_add_cpu(&oleaf->lf_entries, -1);
1070 if (!prev)
1071 prev = dent;
1073 moved = 1;
1074 } else {
1075 prev = dent;
1077 dent = next;
1078 } while (dent);
1080 oleaf->lf_depth = nleaf->lf_depth;
1082 error = gfs2_meta_inode_buffer(dip, &dibh);
1083 if (!gfs2_assert_withdraw(GFS2_SB(&dip->i_inode), !error)) {
1084 gfs2_trans_add_meta(dip->i_gl, dibh);
1085 gfs2_add_inode_blocks(&dip->i_inode, 1);
1086 gfs2_dinode_out(dip, dibh->b_data);
1087 brelse(dibh);
1090 brelse(obh);
1091 brelse(nbh);
1093 return error;
1095 fail_lpfree:
1096 kfree(lp);
1098 fail_brelse:
1099 brelse(obh);
1100 brelse(nbh);
1101 return error;
1105 * dir_double_exhash - Double size of ExHash table
1106 * @dip: The GFS2 dinode
1108 * Returns: 0 on success, error code on failure
1111 static int dir_double_exhash(struct gfs2_inode *dip)
1113 struct buffer_head *dibh;
1114 u32 hsize;
1115 u32 hsize_bytes;
1116 __be64 *hc;
1117 __be64 *hc2, *h;
1118 int x;
1119 int error = 0;
1121 hsize = 1 << dip->i_depth;
1122 hsize_bytes = hsize * sizeof(__be64);
1124 hc = gfs2_dir_get_hash_table(dip);
1125 if (IS_ERR(hc))
1126 return PTR_ERR(hc);
1128 h = hc2 = kmalloc(hsize_bytes * 2, GFP_NOFS | __GFP_NOWARN);
1129 if (hc2 == NULL)
1130 hc2 = __vmalloc(hsize_bytes * 2, GFP_NOFS, PAGE_KERNEL);
1132 if (!hc2)
1133 return -ENOMEM;
1135 error = gfs2_meta_inode_buffer(dip, &dibh);
1136 if (error)
1137 goto out_kfree;
1139 for (x = 0; x < hsize; x++) {
1140 *h++ = *hc;
1141 *h++ = *hc;
1142 hc++;
1145 error = gfs2_dir_write_data(dip, (char *)hc2, 0, hsize_bytes * 2);
1146 if (error != (hsize_bytes * 2))
1147 goto fail;
1149 gfs2_dir_hash_inval(dip);
1150 dip->i_hash_cache = hc2;
1151 dip->i_depth++;
1152 gfs2_dinode_out(dip, dibh->b_data);
1153 brelse(dibh);
1154 return 0;
1156 fail:
1157 /* Replace original hash table & size */
1158 gfs2_dir_write_data(dip, (char *)hc, 0, hsize_bytes);
1159 i_size_write(&dip->i_inode, hsize_bytes);
1160 gfs2_dinode_out(dip, dibh->b_data);
1161 brelse(dibh);
1162 out_kfree:
1163 if (is_vmalloc_addr(hc2))
1164 vfree(hc2);
1165 else
1166 kfree(hc2);
1167 return error;
1171 * compare_dents - compare directory entries by hash value
1172 * @a: first dent
1173 * @b: second dent
1175 * When comparing the hash entries of @a to @b:
1176 * gt: returns 1
1177 * lt: returns -1
1178 * eq: returns 0
1181 static int compare_dents(const void *a, const void *b)
1183 const struct gfs2_dirent *dent_a, *dent_b;
1184 u32 hash_a, hash_b;
1185 int ret = 0;
1187 dent_a = *(const struct gfs2_dirent **)a;
1188 hash_a = be32_to_cpu(dent_a->de_hash);
1190 dent_b = *(const struct gfs2_dirent **)b;
1191 hash_b = be32_to_cpu(dent_b->de_hash);
1193 if (hash_a > hash_b)
1194 ret = 1;
1195 else if (hash_a < hash_b)
1196 ret = -1;
1197 else {
1198 unsigned int len_a = be16_to_cpu(dent_a->de_name_len);
1199 unsigned int len_b = be16_to_cpu(dent_b->de_name_len);
1201 if (len_a > len_b)
1202 ret = 1;
1203 else if (len_a < len_b)
1204 ret = -1;
1205 else
1206 ret = memcmp(dent_a + 1, dent_b + 1, len_a);
1209 return ret;
1213 * do_filldir_main - read out directory entries
1214 * @dip: The GFS2 inode
1215 * @offset: The offset in the file to read from
1216 * @opaque: opaque data to pass to filldir
1217 * @filldir: The function to pass entries to
1218 * @darr: an array of struct gfs2_dirent pointers to read
1219 * @entries: the number of entries in darr
1220 * @copied: pointer to int that's non-zero if a entry has been copied out
1222 * Jump through some hoops to make sure that if there are hash collsions,
1223 * they are read out at the beginning of a buffer. We want to minimize
1224 * the possibility that they will fall into different readdir buffers or
1225 * that someone will want to seek to that location.
1227 * Returns: errno, >0 on exception from filldir
1230 static int do_filldir_main(struct gfs2_inode *dip, u64 *offset,
1231 void *opaque, filldir_t filldir,
1232 const struct gfs2_dirent **darr, u32 entries,
1233 int *copied)
1235 const struct gfs2_dirent *dent, *dent_next;
1236 u64 off, off_next;
1237 unsigned int x, y;
1238 int run = 0;
1239 int error = 0;
1241 sort(darr, entries, sizeof(struct gfs2_dirent *), compare_dents, NULL);
1243 dent_next = darr[0];
1244 off_next = be32_to_cpu(dent_next->de_hash);
1245 off_next = gfs2_disk_hash2offset(off_next);
1247 for (x = 0, y = 1; x < entries; x++, y++) {
1248 dent = dent_next;
1249 off = off_next;
1251 if (y < entries) {
1252 dent_next = darr[y];
1253 off_next = be32_to_cpu(dent_next->de_hash);
1254 off_next = gfs2_disk_hash2offset(off_next);
1256 if (off < *offset)
1257 continue;
1258 *offset = off;
1260 if (off_next == off) {
1261 if (*copied && !run)
1262 return 1;
1263 run = 1;
1264 } else
1265 run = 0;
1266 } else {
1267 if (off < *offset)
1268 continue;
1269 *offset = off;
1272 error = filldir(opaque, (const char *)(dent + 1),
1273 be16_to_cpu(dent->de_name_len),
1274 off, be64_to_cpu(dent->de_inum.no_addr),
1275 be16_to_cpu(dent->de_type));
1276 if (error)
1277 return 1;
1279 *copied = 1;
1282 /* Increment the *offset by one, so the next time we come into the
1283 do_filldir fxn, we get the next entry instead of the last one in the
1284 current leaf */
1286 (*offset)++;
1288 return 0;
1291 static void *gfs2_alloc_sort_buffer(unsigned size)
1293 void *ptr = NULL;
1295 if (size < KMALLOC_MAX_SIZE)
1296 ptr = kmalloc(size, GFP_NOFS | __GFP_NOWARN);
1297 if (!ptr)
1298 ptr = __vmalloc(size, GFP_NOFS, PAGE_KERNEL);
1299 return ptr;
1302 static void gfs2_free_sort_buffer(void *ptr)
1304 if (is_vmalloc_addr(ptr))
1305 vfree(ptr);
1306 else
1307 kfree(ptr);
1310 static int gfs2_dir_read_leaf(struct inode *inode, u64 *offset, void *opaque,
1311 filldir_t filldir, int *copied, unsigned *depth,
1312 u64 leaf_no)
1314 struct gfs2_inode *ip = GFS2_I(inode);
1315 struct gfs2_sbd *sdp = GFS2_SB(inode);
1316 struct buffer_head *bh;
1317 struct gfs2_leaf *lf;
1318 unsigned entries = 0, entries2 = 0;
1319 unsigned leaves = 0;
1320 const struct gfs2_dirent **darr, *dent;
1321 struct dirent_gather g;
1322 struct buffer_head **larr;
1323 int leaf = 0;
1324 int error, i;
1325 u64 lfn = leaf_no;
1327 do {
1328 error = get_leaf(ip, lfn, &bh);
1329 if (error)
1330 goto out;
1331 lf = (struct gfs2_leaf *)bh->b_data;
1332 if (leaves == 0)
1333 *depth = be16_to_cpu(lf->lf_depth);
1334 entries += be16_to_cpu(lf->lf_entries);
1335 leaves++;
1336 lfn = be64_to_cpu(lf->lf_next);
1337 brelse(bh);
1338 } while(lfn);
1340 if (!entries)
1341 return 0;
1343 error = -ENOMEM;
1345 * The extra 99 entries are not normally used, but are a buffer
1346 * zone in case the number of entries in the leaf is corrupt.
1347 * 99 is the maximum number of entries that can fit in a single
1348 * leaf block.
1350 larr = gfs2_alloc_sort_buffer((leaves + entries + 99) * sizeof(void *));
1351 if (!larr)
1352 goto out;
1353 darr = (const struct gfs2_dirent **)(larr + leaves);
1354 g.pdent = darr;
1355 g.offset = 0;
1356 lfn = leaf_no;
1358 do {
1359 error = get_leaf(ip, lfn, &bh);
1360 if (error)
1361 goto out_free;
1362 lf = (struct gfs2_leaf *)bh->b_data;
1363 lfn = be64_to_cpu(lf->lf_next);
1364 if (lf->lf_entries) {
1365 entries2 += be16_to_cpu(lf->lf_entries);
1366 dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size,
1367 gfs2_dirent_gather, NULL, &g);
1368 error = PTR_ERR(dent);
1369 if (IS_ERR(dent))
1370 goto out_free;
1371 if (entries2 != g.offset) {
1372 fs_warn(sdp, "Number of entries corrupt in dir "
1373 "leaf %llu, entries2 (%u) != "
1374 "g.offset (%u)\n",
1375 (unsigned long long)bh->b_blocknr,
1376 entries2, g.offset);
1378 error = -EIO;
1379 goto out_free;
1381 error = 0;
1382 larr[leaf++] = bh;
1383 } else {
1384 brelse(bh);
1386 } while(lfn);
1388 BUG_ON(entries2 != entries);
1389 error = do_filldir_main(ip, offset, opaque, filldir, darr,
1390 entries, copied);
1391 out_free:
1392 for(i = 0; i < leaf; i++)
1393 brelse(larr[i]);
1394 gfs2_free_sort_buffer(larr);
1395 out:
1396 return error;
1400 * gfs2_dir_readahead - Issue read-ahead requests for leaf blocks.
1402 * Note: we can't calculate each index like dir_e_read can because we don't
1403 * have the leaf, and therefore we don't have the depth, and therefore we
1404 * don't have the length. So we have to just read enough ahead to make up
1405 * for the loss of information.
1407 static void gfs2_dir_readahead(struct inode *inode, unsigned hsize, u32 index,
1408 struct file_ra_state *f_ra)
1410 struct gfs2_inode *ip = GFS2_I(inode);
1411 struct gfs2_glock *gl = ip->i_gl;
1412 struct buffer_head *bh;
1413 u64 blocknr = 0, last;
1414 unsigned count;
1416 /* First check if we've already read-ahead for the whole range. */
1417 if (index + MAX_RA_BLOCKS < f_ra->start)
1418 return;
1420 f_ra->start = max((pgoff_t)index, f_ra->start);
1421 for (count = 0; count < MAX_RA_BLOCKS; count++) {
1422 if (f_ra->start >= hsize) /* if exceeded the hash table */
1423 break;
1425 last = blocknr;
1426 blocknr = be64_to_cpu(ip->i_hash_cache[f_ra->start]);
1427 f_ra->start++;
1428 if (blocknr == last)
1429 continue;
1431 bh = gfs2_getbuf(gl, blocknr, 1);
1432 if (trylock_buffer(bh)) {
1433 if (buffer_uptodate(bh)) {
1434 unlock_buffer(bh);
1435 brelse(bh);
1436 continue;
1438 bh->b_end_io = end_buffer_read_sync;
1439 submit_bh(READA | REQ_META, bh);
1440 continue;
1442 brelse(bh);
1447 * dir_e_read - Reads the entries from a directory into a filldir buffer
1448 * @dip: dinode pointer
1449 * @offset: the hash of the last entry read shifted to the right once
1450 * @opaque: buffer for the filldir function to fill
1451 * @filldir: points to the filldir function to use
1453 * Returns: errno
1456 static int dir_e_read(struct inode *inode, u64 *offset, void *opaque,
1457 filldir_t filldir, struct file_ra_state *f_ra)
1459 struct gfs2_inode *dip = GFS2_I(inode);
1460 u32 hsize, len = 0;
1461 u32 hash, index;
1462 __be64 *lp;
1463 int copied = 0;
1464 int error = 0;
1465 unsigned depth = 0;
1467 hsize = 1 << dip->i_depth;
1468 hash = gfs2_dir_offset2hash(*offset);
1469 index = hash >> (32 - dip->i_depth);
1471 if (dip->i_hash_cache == NULL)
1472 f_ra->start = 0;
1473 lp = gfs2_dir_get_hash_table(dip);
1474 if (IS_ERR(lp))
1475 return PTR_ERR(lp);
1477 gfs2_dir_readahead(inode, hsize, index, f_ra);
1479 while (index < hsize) {
1480 error = gfs2_dir_read_leaf(inode, offset, opaque, filldir,
1481 &copied, &depth,
1482 be64_to_cpu(lp[index]));
1483 if (error)
1484 break;
1486 len = 1 << (dip->i_depth - depth);
1487 index = (index & ~(len - 1)) + len;
1490 if (error > 0)
1491 error = 0;
1492 return error;
1495 int gfs2_dir_read(struct inode *inode, u64 *offset, void *opaque,
1496 filldir_t filldir, struct file_ra_state *f_ra)
1498 struct gfs2_inode *dip = GFS2_I(inode);
1499 struct gfs2_sbd *sdp = GFS2_SB(inode);
1500 struct dirent_gather g;
1501 const struct gfs2_dirent **darr, *dent;
1502 struct buffer_head *dibh;
1503 int copied = 0;
1504 int error;
1506 if (!dip->i_entries)
1507 return 0;
1509 if (dip->i_diskflags & GFS2_DIF_EXHASH)
1510 return dir_e_read(inode, offset, opaque, filldir, f_ra);
1512 if (!gfs2_is_stuffed(dip)) {
1513 gfs2_consist_inode(dip);
1514 return -EIO;
1517 error = gfs2_meta_inode_buffer(dip, &dibh);
1518 if (error)
1519 return error;
1521 error = -ENOMEM;
1522 /* 96 is max number of dirents which can be stuffed into an inode */
1523 darr = kmalloc(96 * sizeof(struct gfs2_dirent *), GFP_NOFS);
1524 if (darr) {
1525 g.pdent = darr;
1526 g.offset = 0;
1527 dent = gfs2_dirent_scan(inode, dibh->b_data, dibh->b_size,
1528 gfs2_dirent_gather, NULL, &g);
1529 if (IS_ERR(dent)) {
1530 error = PTR_ERR(dent);
1531 goto out;
1533 if (dip->i_entries != g.offset) {
1534 fs_warn(sdp, "Number of entries corrupt in dir %llu, "
1535 "ip->i_entries (%u) != g.offset (%u)\n",
1536 (unsigned long long)dip->i_no_addr,
1537 dip->i_entries,
1538 g.offset);
1539 error = -EIO;
1540 goto out;
1542 error = do_filldir_main(dip, offset, opaque, filldir, darr,
1543 dip->i_entries, &copied);
1544 out:
1545 kfree(darr);
1548 if (error > 0)
1549 error = 0;
1551 brelse(dibh);
1553 return error;
1557 * gfs2_dir_search - Search a directory
1558 * @dip: The GFS2 inode
1559 * @filename:
1560 * @inode:
1562 * This routine searches a directory for a file or another directory.
1563 * Assumes a glock is held on dip.
1565 * Returns: errno
1568 struct inode *gfs2_dir_search(struct inode *dir, const struct qstr *name)
1570 struct buffer_head *bh;
1571 struct gfs2_dirent *dent;
1572 struct inode *inode;
1574 dent = gfs2_dirent_search(dir, name, gfs2_dirent_find, &bh);
1575 if (dent) {
1576 if (IS_ERR(dent))
1577 return ERR_CAST(dent);
1578 inode = gfs2_inode_lookup(dir->i_sb,
1579 be16_to_cpu(dent->de_type),
1580 be64_to_cpu(dent->de_inum.no_addr),
1581 be64_to_cpu(dent->de_inum.no_formal_ino), 0);
1582 brelse(bh);
1583 return inode;
1585 return ERR_PTR(-ENOENT);
1588 int gfs2_dir_check(struct inode *dir, const struct qstr *name,
1589 const struct gfs2_inode *ip)
1591 struct buffer_head *bh;
1592 struct gfs2_dirent *dent;
1593 int ret = -ENOENT;
1595 dent = gfs2_dirent_search(dir, name, gfs2_dirent_find, &bh);
1596 if (dent) {
1597 if (IS_ERR(dent))
1598 return PTR_ERR(dent);
1599 if (ip) {
1600 if (be64_to_cpu(dent->de_inum.no_addr) != ip->i_no_addr)
1601 goto out;
1602 if (be64_to_cpu(dent->de_inum.no_formal_ino) !=
1603 ip->i_no_formal_ino)
1604 goto out;
1605 if (unlikely(IF2DT(ip->i_inode.i_mode) !=
1606 be16_to_cpu(dent->de_type))) {
1607 gfs2_consist_inode(GFS2_I(dir));
1608 ret = -EIO;
1609 goto out;
1612 ret = 0;
1613 out:
1614 brelse(bh);
1616 return ret;
1619 static int dir_new_leaf(struct inode *inode, const struct qstr *name)
1621 struct buffer_head *bh, *obh;
1622 struct gfs2_inode *ip = GFS2_I(inode);
1623 struct gfs2_leaf *leaf, *oleaf;
1624 int error;
1625 u32 index;
1626 u64 bn;
1628 index = name->hash >> (32 - ip->i_depth);
1629 error = get_first_leaf(ip, index, &obh);
1630 if (error)
1631 return error;
1632 do {
1633 oleaf = (struct gfs2_leaf *)obh->b_data;
1634 bn = be64_to_cpu(oleaf->lf_next);
1635 if (!bn)
1636 break;
1637 brelse(obh);
1638 error = get_leaf(ip, bn, &obh);
1639 if (error)
1640 return error;
1641 } while(1);
1643 gfs2_trans_add_meta(ip->i_gl, obh);
1645 leaf = new_leaf(inode, &bh, be16_to_cpu(oleaf->lf_depth));
1646 if (!leaf) {
1647 brelse(obh);
1648 return -ENOSPC;
1650 oleaf->lf_next = cpu_to_be64(bh->b_blocknr);
1651 brelse(bh);
1652 brelse(obh);
1654 error = gfs2_meta_inode_buffer(ip, &bh);
1655 if (error)
1656 return error;
1657 gfs2_trans_add_meta(ip->i_gl, bh);
1658 gfs2_add_inode_blocks(&ip->i_inode, 1);
1659 gfs2_dinode_out(ip, bh->b_data);
1660 brelse(bh);
1661 return 0;
1665 * gfs2_dir_add - Add new filename into directory
1666 * @dip: The GFS2 inode
1667 * @filename: The new name
1668 * @inode: The inode number of the entry
1669 * @type: The type of the entry
1671 * Returns: 0 on success, error code on failure
1674 int gfs2_dir_add(struct inode *inode, const struct qstr *name,
1675 const struct gfs2_inode *nip)
1677 struct gfs2_inode *ip = GFS2_I(inode);
1678 struct buffer_head *bh;
1679 struct gfs2_dirent *dent;
1680 struct gfs2_leaf *leaf;
1681 int error;
1683 while(1) {
1684 dent = gfs2_dirent_search(inode, name, gfs2_dirent_find_space,
1685 &bh);
1686 if (dent) {
1687 if (IS_ERR(dent))
1688 return PTR_ERR(dent);
1689 dent = gfs2_init_dirent(inode, dent, name, bh);
1690 gfs2_inum_out(nip, dent);
1691 dent->de_type = cpu_to_be16(IF2DT(nip->i_inode.i_mode));
1692 if (ip->i_diskflags & GFS2_DIF_EXHASH) {
1693 leaf = (struct gfs2_leaf *)bh->b_data;
1694 be16_add_cpu(&leaf->lf_entries, 1);
1696 brelse(bh);
1697 ip->i_entries++;
1698 ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
1699 if (S_ISDIR(nip->i_inode.i_mode))
1700 inc_nlink(&ip->i_inode);
1701 mark_inode_dirty(inode);
1702 error = 0;
1703 break;
1705 if (!(ip->i_diskflags & GFS2_DIF_EXHASH)) {
1706 error = dir_make_exhash(inode);
1707 if (error)
1708 break;
1709 continue;
1711 error = dir_split_leaf(inode, name);
1712 if (error == 0)
1713 continue;
1714 if (error < 0)
1715 break;
1716 if (ip->i_depth < GFS2_DIR_MAX_DEPTH) {
1717 error = dir_double_exhash(ip);
1718 if (error)
1719 break;
1720 error = dir_split_leaf(inode, name);
1721 if (error < 0)
1722 break;
1723 if (error == 0)
1724 continue;
1726 error = dir_new_leaf(inode, name);
1727 if (!error)
1728 continue;
1729 error = -ENOSPC;
1730 break;
1732 return error;
1737 * gfs2_dir_del - Delete a directory entry
1738 * @dip: The GFS2 inode
1739 * @filename: The filename
1741 * Returns: 0 on success, error code on failure
1744 int gfs2_dir_del(struct gfs2_inode *dip, const struct dentry *dentry)
1746 const struct qstr *name = &dentry->d_name;
1747 struct gfs2_dirent *dent, *prev = NULL;
1748 struct buffer_head *bh;
1750 /* Returns _either_ the entry (if its first in block) or the
1751 previous entry otherwise */
1752 dent = gfs2_dirent_search(&dip->i_inode, name, gfs2_dirent_prev, &bh);
1753 if (!dent) {
1754 gfs2_consist_inode(dip);
1755 return -EIO;
1757 if (IS_ERR(dent)) {
1758 gfs2_consist_inode(dip);
1759 return PTR_ERR(dent);
1761 /* If not first in block, adjust pointers accordingly */
1762 if (gfs2_dirent_find(dent, name, NULL) == 0) {
1763 prev = dent;
1764 dent = (struct gfs2_dirent *)((char *)dent + be16_to_cpu(prev->de_rec_len));
1767 dirent_del(dip, bh, prev, dent);
1768 if (dip->i_diskflags & GFS2_DIF_EXHASH) {
1769 struct gfs2_leaf *leaf = (struct gfs2_leaf *)bh->b_data;
1770 u16 entries = be16_to_cpu(leaf->lf_entries);
1771 if (!entries)
1772 gfs2_consist_inode(dip);
1773 leaf->lf_entries = cpu_to_be16(--entries);
1775 brelse(bh);
1777 if (!dip->i_entries)
1778 gfs2_consist_inode(dip);
1779 dip->i_entries--;
1780 dip->i_inode.i_mtime = dip->i_inode.i_ctime = CURRENT_TIME;
1781 if (S_ISDIR(dentry->d_inode->i_mode))
1782 drop_nlink(&dip->i_inode);
1783 mark_inode_dirty(&dip->i_inode);
1785 return 0;
1789 * gfs2_dir_mvino - Change inode number of directory entry
1790 * @dip: The GFS2 inode
1791 * @filename:
1792 * @new_inode:
1794 * This routine changes the inode number of a directory entry. It's used
1795 * by rename to change ".." when a directory is moved.
1796 * Assumes a glock is held on dvp.
1798 * Returns: errno
1801 int gfs2_dir_mvino(struct gfs2_inode *dip, const struct qstr *filename,
1802 const struct gfs2_inode *nip, unsigned int new_type)
1804 struct buffer_head *bh;
1805 struct gfs2_dirent *dent;
1806 int error;
1808 dent = gfs2_dirent_search(&dip->i_inode, filename, gfs2_dirent_find, &bh);
1809 if (!dent) {
1810 gfs2_consist_inode(dip);
1811 return -EIO;
1813 if (IS_ERR(dent))
1814 return PTR_ERR(dent);
1816 gfs2_trans_add_meta(dip->i_gl, bh);
1817 gfs2_inum_out(nip, dent);
1818 dent->de_type = cpu_to_be16(new_type);
1820 if (dip->i_diskflags & GFS2_DIF_EXHASH) {
1821 brelse(bh);
1822 error = gfs2_meta_inode_buffer(dip, &bh);
1823 if (error)
1824 return error;
1825 gfs2_trans_add_meta(dip->i_gl, bh);
1828 dip->i_inode.i_mtime = dip->i_inode.i_ctime = CURRENT_TIME;
1829 gfs2_dinode_out(dip, bh->b_data);
1830 brelse(bh);
1831 return 0;
1835 * leaf_dealloc - Deallocate a directory leaf
1836 * @dip: the directory
1837 * @index: the hash table offset in the directory
1838 * @len: the number of pointers to this leaf
1839 * @leaf_no: the leaf number
1840 * @leaf_bh: buffer_head for the starting leaf
1841 * last_dealloc: 1 if this is the final dealloc for the leaf, else 0
1843 * Returns: errno
1846 static int leaf_dealloc(struct gfs2_inode *dip, u32 index, u32 len,
1847 u64 leaf_no, struct buffer_head *leaf_bh,
1848 int last_dealloc)
1850 struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
1851 struct gfs2_leaf *tmp_leaf;
1852 struct gfs2_rgrp_list rlist;
1853 struct buffer_head *bh, *dibh;
1854 u64 blk, nblk;
1855 unsigned int rg_blocks = 0, l_blocks = 0;
1856 char *ht;
1857 unsigned int x, size = len * sizeof(u64);
1858 int error;
1860 error = gfs2_rindex_update(sdp);
1861 if (error)
1862 return error;
1864 memset(&rlist, 0, sizeof(struct gfs2_rgrp_list));
1866 ht = kzalloc(size, GFP_NOFS);
1867 if (ht == NULL)
1868 ht = vzalloc(size);
1869 if (!ht)
1870 return -ENOMEM;
1872 error = gfs2_quota_hold(dip, NO_UID_QUOTA_CHANGE, NO_GID_QUOTA_CHANGE);
1873 if (error)
1874 goto out;
1876 /* Count the number of leaves */
1877 bh = leaf_bh;
1879 for (blk = leaf_no; blk; blk = nblk) {
1880 if (blk != leaf_no) {
1881 error = get_leaf(dip, blk, &bh);
1882 if (error)
1883 goto out_rlist;
1885 tmp_leaf = (struct gfs2_leaf *)bh->b_data;
1886 nblk = be64_to_cpu(tmp_leaf->lf_next);
1887 if (blk != leaf_no)
1888 brelse(bh);
1890 gfs2_rlist_add(dip, &rlist, blk);
1891 l_blocks++;
1894 gfs2_rlist_alloc(&rlist, LM_ST_EXCLUSIVE);
1896 for (x = 0; x < rlist.rl_rgrps; x++) {
1897 struct gfs2_rgrpd *rgd;
1898 rgd = rlist.rl_ghs[x].gh_gl->gl_object;
1899 rg_blocks += rgd->rd_length;
1902 error = gfs2_glock_nq_m(rlist.rl_rgrps, rlist.rl_ghs);
1903 if (error)
1904 goto out_rlist;
1906 error = gfs2_trans_begin(sdp,
1907 rg_blocks + (DIV_ROUND_UP(size, sdp->sd_jbsize) + 1) +
1908 RES_DINODE + RES_STATFS + RES_QUOTA, l_blocks);
1909 if (error)
1910 goto out_rg_gunlock;
1912 bh = leaf_bh;
1914 for (blk = leaf_no; blk; blk = nblk) {
1915 if (blk != leaf_no) {
1916 error = get_leaf(dip, blk, &bh);
1917 if (error)
1918 goto out_end_trans;
1920 tmp_leaf = (struct gfs2_leaf *)bh->b_data;
1921 nblk = be64_to_cpu(tmp_leaf->lf_next);
1922 if (blk != leaf_no)
1923 brelse(bh);
1925 gfs2_free_meta(dip, blk, 1);
1926 gfs2_add_inode_blocks(&dip->i_inode, -1);
1929 error = gfs2_dir_write_data(dip, ht, index * sizeof(u64), size);
1930 if (error != size) {
1931 if (error >= 0)
1932 error = -EIO;
1933 goto out_end_trans;
1936 error = gfs2_meta_inode_buffer(dip, &dibh);
1937 if (error)
1938 goto out_end_trans;
1940 gfs2_trans_add_meta(dip->i_gl, dibh);
1941 /* On the last dealloc, make this a regular file in case we crash.
1942 (We don't want to free these blocks a second time.) */
1943 if (last_dealloc)
1944 dip->i_inode.i_mode = S_IFREG;
1945 gfs2_dinode_out(dip, dibh->b_data);
1946 brelse(dibh);
1948 out_end_trans:
1949 gfs2_trans_end(sdp);
1950 out_rg_gunlock:
1951 gfs2_glock_dq_m(rlist.rl_rgrps, rlist.rl_ghs);
1952 out_rlist:
1953 gfs2_rlist_free(&rlist);
1954 gfs2_quota_unhold(dip);
1955 out:
1956 if (is_vmalloc_addr(ht))
1957 vfree(ht);
1958 else
1959 kfree(ht);
1960 return error;
1964 * gfs2_dir_exhash_dealloc - free all the leaf blocks in a directory
1965 * @dip: the directory
1967 * Dealloc all on-disk directory leaves to FREEMETA state
1968 * Change on-disk inode type to "regular file"
1970 * Returns: errno
1973 int gfs2_dir_exhash_dealloc(struct gfs2_inode *dip)
1975 struct buffer_head *bh;
1976 struct gfs2_leaf *leaf;
1977 u32 hsize, len;
1978 u32 index = 0, next_index;
1979 __be64 *lp;
1980 u64 leaf_no;
1981 int error = 0, last;
1983 hsize = 1 << dip->i_depth;
1985 lp = gfs2_dir_get_hash_table(dip);
1986 if (IS_ERR(lp))
1987 return PTR_ERR(lp);
1989 while (index < hsize) {
1990 leaf_no = be64_to_cpu(lp[index]);
1991 if (leaf_no) {
1992 error = get_leaf(dip, leaf_no, &bh);
1993 if (error)
1994 goto out;
1995 leaf = (struct gfs2_leaf *)bh->b_data;
1996 len = 1 << (dip->i_depth - be16_to_cpu(leaf->lf_depth));
1998 next_index = (index & ~(len - 1)) + len;
1999 last = ((next_index >= hsize) ? 1 : 0);
2000 error = leaf_dealloc(dip, index, len, leaf_no, bh,
2001 last);
2002 brelse(bh);
2003 if (error)
2004 goto out;
2005 index = next_index;
2006 } else
2007 index++;
2010 if (index != hsize) {
2011 gfs2_consist_inode(dip);
2012 error = -EIO;
2015 out:
2017 return error;
2021 * gfs2_diradd_alloc_required - find if adding entry will require an allocation
2022 * @ip: the file being written to
2023 * @filname: the filename that's going to be added
2025 * Returns: 1 if alloc required, 0 if not, -ve on error
2028 int gfs2_diradd_alloc_required(struct inode *inode, const struct qstr *name)
2030 struct gfs2_dirent *dent;
2031 struct buffer_head *bh;
2033 dent = gfs2_dirent_search(inode, name, gfs2_dirent_find_space, &bh);
2034 if (!dent) {
2035 return 1;
2037 if (IS_ERR(dent))
2038 return PTR_ERR(dent);
2039 brelse(bh);
2040 return 0;