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TOMOYO Linux Cross Reference
Linux/fs/gfs2/dir.c

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  1 /*
  2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
  3  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
  4  *
  5  * This copyrighted material is made available to anyone wishing to use,
  6  * modify, copy, or redistribute it subject to the terms and conditions
  7  * of the GNU General Public License version 2.
  8  */
  9 
 10 /*
 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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 57 
 58 #include <linux/slab.h>
 59 #include <linux/spinlock.h>
 60 #include <linux/buffer_head.h>
 61 #include <linux/sort.h>
 62 #include <linux/gfs2_ondisk.h>
 63 #include <linux/crc32.h>
 64 #include <linux/vmalloc.h>
 65 #include <linux/bio.h>
 66 
 67 #include "gfs2.h"
 68 #include "incore.h"
 69 #include "dir.h"
 70 #include "glock.h"
 71 #include "inode.h"
 72 #include "meta_io.h"
 73 #include "quota.h"
 74 #include "rgrp.h"
 75 #include "trans.h"
 76 #include "bmap.h"
 77 #include "util.h"
 78 
 79 #define IS_LEAF     1 /* Hashed (leaf) directory */
 80 #define IS_DINODE   2 /* Linear (stuffed dinode block) directory */
 81 
 82 #define MAX_RA_BLOCKS 32 /* max read-ahead blocks */
 83 
 84 #define gfs2_disk_hash2offset(h) (((u64)(h)) >> 1)
 85 #define gfs2_dir_offset2hash(p) ((u32)(((u64)(p)) << 1))
 86 #define GFS2_HASH_INDEX_MASK 0xffffc000
 87 #define GFS2_USE_HASH_FLAG 0x2000
 88 
 89 struct qstr gfs2_qdot __read_mostly;
 90 struct qstr gfs2_qdotdot __read_mostly;
 91 
 92 typedef int (*gfs2_dscan_t)(const struct gfs2_dirent *dent,
 93                             const struct qstr *name, void *opaque);
 94 
 95 int gfs2_dir_get_new_buffer(struct gfs2_inode *ip, u64 block,
 96                             struct buffer_head **bhp)
 97 {
 98         struct buffer_head *bh;
 99 
100         bh = gfs2_meta_new(ip->i_gl, block);
101         gfs2_trans_add_meta(ip->i_gl, bh);
102         gfs2_metatype_set(bh, GFS2_METATYPE_JD, GFS2_FORMAT_JD);
103         gfs2_buffer_clear_tail(bh, sizeof(struct gfs2_meta_header));
104         *bhp = bh;
105         return 0;
106 }
107 
108 static int gfs2_dir_get_existing_buffer(struct gfs2_inode *ip, u64 block,
109                                         struct buffer_head **bhp)
110 {
111         struct buffer_head *bh;
112         int error;
113 
114         error = gfs2_meta_read(ip->i_gl, block, DIO_WAIT, 0, &bh);
115         if (error)
116                 return error;
117         if (gfs2_metatype_check(GFS2_SB(&ip->i_inode), bh, GFS2_METATYPE_JD)) {
118                 brelse(bh);
119                 return -EIO;
120         }
121         *bhp = bh;
122         return 0;
123 }
124 
125 static int gfs2_dir_write_stuffed(struct gfs2_inode *ip, const char *buf,
126                                   unsigned int offset, unsigned int size)
127 {
128         struct buffer_head *dibh;
129         int error;
130 
131         error = gfs2_meta_inode_buffer(ip, &dibh);
132         if (error)
133                 return error;
134 
135         gfs2_trans_add_meta(ip->i_gl, dibh);
136         memcpy(dibh->b_data + offset + sizeof(struct gfs2_dinode), buf, size);
137         if (ip->i_inode.i_size < offset + size)
138                 i_size_write(&ip->i_inode, offset + size);
139         ip->i_inode.i_mtime = ip->i_inode.i_ctime = current_time(&ip->i_inode);
140         gfs2_dinode_out(ip, dibh->b_data);
141 
142         brelse(dibh);
143 
144         return size;
145 }
146 
147 
148 
149 /**
150  * gfs2_dir_write_data - Write directory information to the inode
151  * @ip: The GFS2 inode
152  * @buf: The buffer containing information to be written
153  * @offset: The file offset to start writing at
154  * @size: The amount of data to write
155  *
156  * Returns: The number of bytes correctly written or error code
157  */
158 static int gfs2_dir_write_data(struct gfs2_inode *ip, const char *buf,
159                                u64 offset, unsigned int size)
160 {
161         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
162         struct buffer_head *dibh;
163         u64 lblock, dblock;
164         u32 extlen = 0;
165         unsigned int o;
166         int copied = 0;
167         int error = 0;
168         int new = 0;
169 
170         if (!size)
171                 return 0;
172 
173         if (gfs2_is_stuffed(ip) && offset + size <= gfs2_max_stuffed_size(ip))
174                 return gfs2_dir_write_stuffed(ip, buf, (unsigned int)offset,
175                                               size);
176 
177         if (gfs2_assert_warn(sdp, gfs2_is_jdata(ip)))
178                 return -EINVAL;
179 
180         if (gfs2_is_stuffed(ip)) {
181                 error = gfs2_unstuff_dinode(ip, NULL);
182                 if (error)
183                         return error;
184         }
185 
186         lblock = offset;
187         o = do_div(lblock, sdp->sd_jbsize) + sizeof(struct gfs2_meta_header);
188 
189         while (copied < size) {
190                 unsigned int amount;
191                 struct buffer_head *bh;
192 
193                 amount = size - copied;
194                 if (amount > sdp->sd_sb.sb_bsize - o)
195                         amount = sdp->sd_sb.sb_bsize - o;
196 
197                 if (!extlen) {
198                         new = 1;
199                         error = gfs2_extent_map(&ip->i_inode, lblock, &new,
200                                                 &dblock, &extlen);
201                         if (error)
202                                 goto fail;
203                         error = -EIO;
204                         if (gfs2_assert_withdraw(sdp, dblock))
205                                 goto fail;
206                 }
207 
208                 if (amount == sdp->sd_jbsize || new)
209                         error = gfs2_dir_get_new_buffer(ip, dblock, &bh);
210                 else
211                         error = gfs2_dir_get_existing_buffer(ip, dblock, &bh);
212 
213                 if (error)
214                         goto fail;
215 
216                 gfs2_trans_add_meta(ip->i_gl, bh);
217                 memcpy(bh->b_data + o, buf, amount);
218                 brelse(bh);
219 
220                 buf += amount;
221                 copied += amount;
222                 lblock++;
223                 dblock++;
224                 extlen--;
225 
226                 o = sizeof(struct gfs2_meta_header);
227         }
228 
229 out:
230         error = gfs2_meta_inode_buffer(ip, &dibh);
231         if (error)
232                 return error;
233 
234         if (ip->i_inode.i_size < offset + copied)
235                 i_size_write(&ip->i_inode, offset + copied);
236         ip->i_inode.i_mtime = ip->i_inode.i_ctime = current_time(&ip->i_inode);
237 
238         gfs2_trans_add_meta(ip->i_gl, dibh);
239         gfs2_dinode_out(ip, dibh->b_data);
240         brelse(dibh);
241 
242         return copied;
243 fail:
244         if (copied)
245                 goto out;
246         return error;
247 }
248 
249 static int gfs2_dir_read_stuffed(struct gfs2_inode *ip, __be64 *buf,
250                                  unsigned int size)
251 {
252         struct buffer_head *dibh;
253         int error;
254 
255         error = gfs2_meta_inode_buffer(ip, &dibh);
256         if (!error) {
257                 memcpy(buf, dibh->b_data + sizeof(struct gfs2_dinode), size);
258                 brelse(dibh);
259         }
260 
261         return (error) ? error : size;
262 }
263 
264 
265 /**
266  * gfs2_dir_read_data - Read a data from a directory inode
267  * @ip: The GFS2 Inode
268  * @buf: The buffer to place result into
269  * @size: Amount of data to transfer
270  *
271  * Returns: The amount of data actually copied or the error
272  */
273 static int gfs2_dir_read_data(struct gfs2_inode *ip, __be64 *buf,
274                               unsigned int size)
275 {
276         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
277         u64 lblock, dblock;
278         u32 extlen = 0;
279         unsigned int o;
280         int copied = 0;
281         int error = 0;
282 
283         if (gfs2_is_stuffed(ip))
284                 return gfs2_dir_read_stuffed(ip, buf, size);
285 
286         if (gfs2_assert_warn(sdp, gfs2_is_jdata(ip)))
287                 return -EINVAL;
288 
289         lblock = 0;
290         o = do_div(lblock, sdp->sd_jbsize) + sizeof(struct gfs2_meta_header);
291 
292         while (copied < size) {
293                 unsigned int amount;
294                 struct buffer_head *bh;
295                 int new;
296 
297                 amount = size - copied;
298                 if (amount > sdp->sd_sb.sb_bsize - o)
299                         amount = sdp->sd_sb.sb_bsize - o;
300 
301                 if (!extlen) {
302                         new = 0;
303                         error = gfs2_extent_map(&ip->i_inode, lblock, &new,
304                                                 &dblock, &extlen);
305                         if (error || !dblock)
306                                 goto fail;
307                         BUG_ON(extlen < 1);
308                         bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
309                 } else {
310                         error = gfs2_meta_read(ip->i_gl, dblock, DIO_WAIT, 0, &bh);
311                         if (error)
312                                 goto fail;
313                 }
314                 error = gfs2_metatype_check(sdp, bh, GFS2_METATYPE_JD);
315                 if (error) {
316                         brelse(bh);
317                         goto fail;
318                 }
319                 dblock++;
320                 extlen--;
321                 memcpy(buf, bh->b_data + o, amount);
322                 brelse(bh);
323                 buf += (amount/sizeof(__be64));
324                 copied += amount;
325                 lblock++;
326                 o = sizeof(struct gfs2_meta_header);
327         }
328 
329         return copied;
330 fail:
331         return (copied) ? copied : error;
332 }
333 
334 /**
335  * gfs2_dir_get_hash_table - Get pointer to the dir hash table
336  * @ip: The inode in question
337  *
338  * Returns: The hash table or an error
339  */
340 
341 static __be64 *gfs2_dir_get_hash_table(struct gfs2_inode *ip)
342 {
343         struct inode *inode = &ip->i_inode;
344         int ret;
345         u32 hsize;
346         __be64 *hc;
347 
348         BUG_ON(!(ip->i_diskflags & GFS2_DIF_EXHASH));
349 
350         hc = ip->i_hash_cache;
351         if (hc)
352                 return hc;
353 
354         hsize = BIT(ip->i_depth);
355         hsize *= sizeof(__be64);
356         if (hsize != i_size_read(&ip->i_inode)) {
357                 gfs2_consist_inode(ip);
358                 return ERR_PTR(-EIO);
359         }
360 
361         hc = kmalloc(hsize, GFP_NOFS | __GFP_NOWARN);
362         if (hc == NULL)
363                 hc = __vmalloc(hsize, GFP_NOFS, PAGE_KERNEL);
364 
365         if (hc == NULL)
366                 return ERR_PTR(-ENOMEM);
367 
368         ret = gfs2_dir_read_data(ip, hc, hsize);
369         if (ret < 0) {
370                 kvfree(hc);
371                 return ERR_PTR(ret);
372         }
373 
374         spin_lock(&inode->i_lock);
375         if (likely(!ip->i_hash_cache)) {
376                 ip->i_hash_cache = hc;
377                 hc = NULL;
378         }
379         spin_unlock(&inode->i_lock);
380         kvfree(hc);
381 
382         return ip->i_hash_cache;
383 }
384 
385 /**
386  * gfs2_dir_hash_inval - Invalidate dir hash
387  * @ip: The directory inode
388  *
389  * Must be called with an exclusive glock, or during glock invalidation.
390  */
391 void gfs2_dir_hash_inval(struct gfs2_inode *ip)
392 {
393         __be64 *hc;
394 
395         spin_lock(&ip->i_inode.i_lock);
396         hc = ip->i_hash_cache;
397         ip->i_hash_cache = NULL;
398         spin_unlock(&ip->i_inode.i_lock);
399 
400         kvfree(hc);
401 }
402 
403 static inline int gfs2_dirent_sentinel(const struct gfs2_dirent *dent)
404 {
405         return dent->de_inum.no_addr == 0 || dent->de_inum.no_formal_ino == 0;
406 }
407 
408 static inline int __gfs2_dirent_find(const struct gfs2_dirent *dent,
409                                      const struct qstr *name, int ret)
410 {
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;
417 }
418 
419 static int gfs2_dirent_find(const struct gfs2_dirent *dent,
420                             const struct qstr *name,
421                             void *opaque)
422 {
423         return __gfs2_dirent_find(dent, name, 1);
424 }
425 
426 static int gfs2_dirent_prev(const struct gfs2_dirent *dent,
427                             const struct qstr *name,
428                             void *opaque)
429 {
430         return __gfs2_dirent_find(dent, name, 2);
431 }
432 
433 /*
434  * name->name holds ptr to start of block.
435  * name->len holds size of block.
436  */
437 static int gfs2_dirent_last(const struct gfs2_dirent *dent,
438                             const struct qstr *name,
439                             void *opaque)
440 {
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;
446 }
447 
448 /* Look for the dirent that contains the offset specified in data. Once we
449  * find that dirent, there must be space available there for the new dirent */
450 static int gfs2_dirent_find_offset(const struct gfs2_dirent *dent,
451                                   const struct qstr *name,
452                                   void *ptr)
453 {
454         unsigned required = GFS2_DIRENT_SIZE(name->len);
455         unsigned actual = GFS2_DIRENT_SIZE(be16_to_cpu(dent->de_name_len));
456         unsigned totlen = be16_to_cpu(dent->de_rec_len);
457 
458         if (ptr < (void *)dent || ptr >= (void *)dent + totlen)
459                 return 0;
460         if (gfs2_dirent_sentinel(dent))
461                 actual = 0;
462         if (ptr < (void *)dent + actual)
463                 return -1;
464         if ((void *)dent + totlen >= ptr + required)
465                 return 1;
466         return -1;
467 }
468 
469 static int gfs2_dirent_find_space(const struct gfs2_dirent *dent,
470                                   const struct qstr *name,
471                                   void *opaque)
472 {
473         unsigned required = GFS2_DIRENT_SIZE(name->len);
474         unsigned actual = GFS2_DIRENT_SIZE(be16_to_cpu(dent->de_name_len));
475         unsigned totlen = be16_to_cpu(dent->de_rec_len);
476 
477         if (gfs2_dirent_sentinel(dent))
478                 actual = 0;
479         if (totlen - actual >= required)
480                 return 1;
481         return 0;
482 }
483 
484 struct dirent_gather {
485         const struct gfs2_dirent **pdent;
486         unsigned offset;
487 };
488 
489 static int gfs2_dirent_gather(const struct gfs2_dirent *dent,
490                               const struct qstr *name,
491                               void *opaque)
492 {
493         struct dirent_gather *g = opaque;
494         if (!gfs2_dirent_sentinel(dent)) {
495                 g->pdent[g->offset++] = dent;
496         }
497         return 0;
498 }
499 
500 /*
501  * Other possible things to check:
502  * - Inode located within filesystem size (and on valid block)
503  * - Valid directory entry type
504  * Not sure how heavy-weight we want to make this... could also check
505  * hash is correct for example, but that would take a lot of extra time.
506  * For now the most important thing is to check that the various sizes
507  * are correct.
508  */
509 static int gfs2_check_dirent(struct gfs2_dirent *dent, unsigned int offset,
510                              unsigned int size, unsigned int len, int first)
511 {
512         const char *msg = "gfs2_dirent too small";
513         if (unlikely(size < sizeof(struct gfs2_dirent)))
514                 goto error;
515         msg = "gfs2_dirent misaligned";
516         if (unlikely(offset & 0x7))
517                 goto error;
518         msg = "gfs2_dirent points beyond end of block";
519         if (unlikely(offset + size > len))
520                 goto error;
521         msg = "zero inode number";
522         if (unlikely(!first && gfs2_dirent_sentinel(dent)))
523                 goto error;
524         msg = "name length is greater than space in dirent";
525         if (!gfs2_dirent_sentinel(dent) &&
526             unlikely(sizeof(struct gfs2_dirent)+be16_to_cpu(dent->de_name_len) >
527                      size))
528                 goto error;
529         return 0;
530 error:
531         pr_warn("%s: %s (%s)\n",
532                 __func__, msg, first ? "first in block" : "not first in block");
533         return -EIO;
534 }
535 
536 static int gfs2_dirent_offset(const void *buf)
537 {
538         const struct gfs2_meta_header *h = buf;
539         int offset;
540 
541         BUG_ON(buf == NULL);
542 
543         switch(be32_to_cpu(h->mh_type)) {
544         case GFS2_METATYPE_LF:
545                 offset = sizeof(struct gfs2_leaf);
546                 break;
547         case GFS2_METATYPE_DI:
548                 offset = sizeof(struct gfs2_dinode);
549                 break;
550         default:
551                 goto wrong_type;
552         }
553         return offset;
554 wrong_type:
555         pr_warn("%s: wrong block type %u\n", __func__, be32_to_cpu(h->mh_type));
556         return -1;
557 }
558 
559 static struct gfs2_dirent *gfs2_dirent_scan(struct inode *inode, void *buf,
560                                             unsigned int len, gfs2_dscan_t scan,
561                                             const struct qstr *name,
562                                             void *opaque)
563 {
564         struct gfs2_dirent *dent, *prev;
565         unsigned offset;
566         unsigned size;
567         int ret = 0;
568 
569         ret = gfs2_dirent_offset(buf);
570         if (ret < 0)
571                 goto consist_inode;
572 
573         offset = ret;
574         prev = NULL;
575         dent = buf + offset;
576         size = be16_to_cpu(dent->de_rec_len);
577         if (gfs2_check_dirent(dent, offset, size, len, 1))
578                 goto consist_inode;
579         do {
580                 ret = scan(dent, name, opaque);
581                 if (ret)
582                         break;
583                 offset += size;
584                 if (offset == len)
585                         break;
586                 prev = dent;
587                 dent = buf + offset;
588                 size = be16_to_cpu(dent->de_rec_len);
589                 if (gfs2_check_dirent(dent, offset, size, len, 0))
590                         goto consist_inode;
591         } while(1);
592 
593         switch(ret) {
594         case 0:
595                 return NULL;
596         case 1:
597                 return dent;
598         case 2:
599                 return prev ? prev : dent;
600         default:
601                 BUG_ON(ret > 0);
602                 return ERR_PTR(ret);
603         }
604 
605 consist_inode:
606         gfs2_consist_inode(GFS2_I(inode));
607         return ERR_PTR(-EIO);
608 }
609 
610 static int dirent_check_reclen(struct gfs2_inode *dip,
611                                const struct gfs2_dirent *d, const void *end_p)
612 {
613         const void *ptr = d;
614         u16 rec_len = be16_to_cpu(d->de_rec_len);
615 
616         if (unlikely(rec_len < sizeof(struct gfs2_dirent)))
617                 goto broken;
618         ptr += rec_len;
619         if (ptr < end_p)
620                 return rec_len;
621         if (ptr == end_p)
622                 return -ENOENT;
623 broken:
624         gfs2_consist_inode(dip);
625         return -EIO;
626 }
627 
628 /**
629  * dirent_next - Next dirent
630  * @dip: the directory
631  * @bh: The buffer
632  * @dent: Pointer to list of dirents
633  *
634  * Returns: 0 on success, error code otherwise
635  */
636 
637 static int dirent_next(struct gfs2_inode *dip, struct buffer_head *bh,
638                        struct gfs2_dirent **dent)
639 {
640         struct gfs2_dirent *cur = *dent, *tmp;
641         char *bh_end = bh->b_data + bh->b_size;
642         int ret;
643 
644         ret = dirent_check_reclen(dip, cur, bh_end);
645         if (ret < 0)
646                 return ret;
647 
648         tmp = (void *)cur + ret;
649         ret = dirent_check_reclen(dip, tmp, bh_end);
650         if (ret == -EIO)
651                 return ret;
652 
653         /* Only the first dent could ever have de_inum.no_addr == 0 */
654         if (gfs2_dirent_sentinel(tmp)) {
655                 gfs2_consist_inode(dip);
656                 return -EIO;
657         }
658 
659         *dent = tmp;
660         return 0;
661 }
662 
663 /**
664  * dirent_del - Delete a dirent
665  * @dip: The GFS2 inode
666  * @bh: The buffer
667  * @prev: The previous dirent
668  * @cur: The current dirent
669  *
670  */
671 
672 static void dirent_del(struct gfs2_inode *dip, struct buffer_head *bh,
673                        struct gfs2_dirent *prev, struct gfs2_dirent *cur)
674 {
675         u16 cur_rec_len, prev_rec_len;
676 
677         if (gfs2_dirent_sentinel(cur)) {
678                 gfs2_consist_inode(dip);
679                 return;
680         }
681 
682         gfs2_trans_add_meta(dip->i_gl, bh);
683 
684         /* If there is no prev entry, this is the first entry in the block.
685            The de_rec_len is already as big as it needs to be.  Just zero
686            out the inode number and return.  */
687 
688         if (!prev) {
689                 cur->de_inum.no_addr = 0;
690                 cur->de_inum.no_formal_ino = 0;
691                 return;
692         }
693 
694         /*  Combine this dentry with the previous one.  */
695 
696         prev_rec_len = be16_to_cpu(prev->de_rec_len);
697         cur_rec_len = be16_to_cpu(cur->de_rec_len);
698 
699         if ((char *)prev + prev_rec_len != (char *)cur)
700                 gfs2_consist_inode(dip);
701         if ((char *)cur + cur_rec_len > bh->b_data + bh->b_size)
702                 gfs2_consist_inode(dip);
703 
704         prev_rec_len += cur_rec_len;
705         prev->de_rec_len = cpu_to_be16(prev_rec_len);
706 }
707 
708 
709 static struct gfs2_dirent *do_init_dirent(struct inode *inode,
710                                           struct gfs2_dirent *dent,
711                                           const struct qstr *name,
712                                           struct buffer_head *bh,
713                                           unsigned offset)
714 {
715         struct gfs2_inode *ip = GFS2_I(inode);
716         struct gfs2_dirent *ndent;
717         unsigned totlen;
718 
719         totlen = be16_to_cpu(dent->de_rec_len);
720         BUG_ON(offset + name->len > totlen);
721         gfs2_trans_add_meta(ip->i_gl, bh);
722         ndent = (struct gfs2_dirent *)((char *)dent + offset);
723         dent->de_rec_len = cpu_to_be16(offset);
724         gfs2_qstr2dirent(name, totlen - offset, ndent);
725         return ndent;
726 }
727 
728 
729 /*
730  * Takes a dent from which to grab space as an argument. Returns the
731  * newly created dent.
732  */
733 static struct gfs2_dirent *gfs2_init_dirent(struct inode *inode,
734                                             struct gfs2_dirent *dent,
735                                             const struct qstr *name,
736                                             struct buffer_head *bh)
737 {
738         unsigned offset = 0;
739 
740         if (!gfs2_dirent_sentinel(dent))
741                 offset = GFS2_DIRENT_SIZE(be16_to_cpu(dent->de_name_len));
742         return do_init_dirent(inode, dent, name, bh, offset);
743 }
744 
745 static struct gfs2_dirent *gfs2_dirent_split_alloc(struct inode *inode,
746                                                    struct buffer_head *bh,
747                                                    const struct qstr *name,
748                                                    void *ptr)
749 {
750         struct gfs2_dirent *dent;
751         dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size,
752                                 gfs2_dirent_find_offset, name, ptr);
753         if (!dent || IS_ERR(dent))
754                 return dent;
755         return do_init_dirent(inode, dent, name, bh,
756                               (unsigned)(ptr - (void *)dent));
757 }
758 
759 static int get_leaf(struct gfs2_inode *dip, u64 leaf_no,
760                     struct buffer_head **bhp)
761 {
762         int error;
763 
764         error = gfs2_meta_read(dip->i_gl, leaf_no, DIO_WAIT, 0, bhp);
765         if (!error && gfs2_metatype_check(GFS2_SB(&dip->i_inode), *bhp, GFS2_METATYPE_LF)) {
766                 /* pr_info("block num=%llu\n", leaf_no); */
767                 error = -EIO;
768         }
769 
770         return error;
771 }
772 
773 /**
774  * get_leaf_nr - Get a leaf number associated with the index
775  * @dip: The GFS2 inode
776  * @index:
777  * @leaf_out:
778  *
779  * Returns: 0 on success, error code otherwise
780  */
781 
782 static int get_leaf_nr(struct gfs2_inode *dip, u32 index,
783                        u64 *leaf_out)
784 {
785         __be64 *hash;
786         int error;
787 
788         hash = gfs2_dir_get_hash_table(dip);
789         error = PTR_ERR_OR_ZERO(hash);
790 
791         if (!error)
792                 *leaf_out = be64_to_cpu(*(hash + index));
793 
794         return error;
795 }
796 
797 static int get_first_leaf(struct gfs2_inode *dip, u32 index,
798                           struct buffer_head **bh_out)
799 {
800         u64 leaf_no;
801         int error;
802 
803         error = get_leaf_nr(dip, index, &leaf_no);
804         if (!error)
805                 error = get_leaf(dip, leaf_no, bh_out);
806 
807         return error;
808 }
809 
810 static struct gfs2_dirent *gfs2_dirent_search(struct inode *inode,
811                                               const struct qstr *name,
812                                               gfs2_dscan_t scan,
813                                               struct buffer_head **pbh)
814 {
815         struct buffer_head *bh;
816         struct gfs2_dirent *dent;
817         struct gfs2_inode *ip = GFS2_I(inode);
818         int error;
819 
820         if (ip->i_diskflags & GFS2_DIF_EXHASH) {
821                 struct gfs2_leaf *leaf;
822                 unsigned int hsize = BIT(ip->i_depth);
823                 unsigned int index;
824                 u64 ln;
825                 if (hsize * sizeof(u64) != i_size_read(inode)) {
826                         gfs2_consist_inode(ip);
827                         return ERR_PTR(-EIO);
828                 }
829 
830                 index = name->hash >> (32 - ip->i_depth);
831                 error = get_first_leaf(ip, index, &bh);
832                 if (error)
833                         return ERR_PTR(error);
834                 do {
835                         dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size,
836                                                 scan, name, NULL);
837                         if (dent)
838                                 goto got_dent;
839                         leaf = (struct gfs2_leaf *)bh->b_data;
840                         ln = be64_to_cpu(leaf->lf_next);
841                         brelse(bh);
842                         if (!ln)
843                                 break;
844 
845                         error = get_leaf(ip, ln, &bh);
846                 } while(!error);
847 
848                 return error ? ERR_PTR(error) : NULL;
849         }
850 
851 
852         error = gfs2_meta_inode_buffer(ip, &bh);
853         if (error)
854                 return ERR_PTR(error);
855         dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size, scan, name, NULL);
856 got_dent:
857         if (unlikely(dent == NULL || IS_ERR(dent))) {
858                 brelse(bh);
859                 bh = NULL;
860         }
861         *pbh = bh;
862         return dent;
863 }
864 
865 static struct gfs2_leaf *new_leaf(struct inode *inode, struct buffer_head **pbh, u16 depth)
866 {
867         struct gfs2_inode *ip = GFS2_I(inode);
868         unsigned int n = 1;
869         u64 bn;
870         int error;
871         struct buffer_head *bh;
872         struct gfs2_leaf *leaf;
873         struct gfs2_dirent *dent;
874         struct timespec64 tv = current_time(inode);
875 
876         error = gfs2_alloc_blocks(ip, &bn, &n, 0, NULL);
877         if (error)
878                 return NULL;
879         bh = gfs2_meta_new(ip->i_gl, bn);
880         if (!bh)
881                 return NULL;
882 
883         gfs2_trans_add_unrevoke(GFS2_SB(inode), bn, 1);
884         gfs2_trans_add_meta(ip->i_gl, bh);
885         gfs2_metatype_set(bh, GFS2_METATYPE_LF, GFS2_FORMAT_LF);
886         leaf = (struct gfs2_leaf *)bh->b_data;
887         leaf->lf_depth = cpu_to_be16(depth);
888         leaf->lf_entries = 0;
889         leaf->lf_dirent_format = cpu_to_be32(GFS2_FORMAT_DE);
890         leaf->lf_next = 0;
891         leaf->lf_inode = cpu_to_be64(ip->i_no_addr);
892         leaf->lf_dist = cpu_to_be32(1);
893         leaf->lf_nsec = cpu_to_be32(tv.tv_nsec);
894         leaf->lf_sec = cpu_to_be64(tv.tv_sec);
895         memset(leaf->lf_reserved2, 0, sizeof(leaf->lf_reserved2));
896         dent = (struct gfs2_dirent *)(leaf+1);
897         gfs2_qstr2dirent(&empty_name, bh->b_size - sizeof(struct gfs2_leaf), dent);
898         *pbh = bh;
899         return leaf;
900 }
901 
902 /**
903  * dir_make_exhash - Convert a stuffed directory into an ExHash directory
904  * @dip: The GFS2 inode
905  *
906  * Returns: 0 on success, error code otherwise
907  */
908 
909 static int dir_make_exhash(struct inode *inode)
910 {
911         struct gfs2_inode *dip = GFS2_I(inode);
912         struct gfs2_sbd *sdp = GFS2_SB(inode);
913         struct gfs2_dirent *dent;
914         struct qstr args;
915         struct buffer_head *bh, *dibh;
916         struct gfs2_leaf *leaf;
917         int y;
918         u32 x;
919         __be64 *lp;
920         u64 bn;
921         int error;
922 
923         error = gfs2_meta_inode_buffer(dip, &dibh);
924         if (error)
925                 return error;
926 
927         /*  Turn over a new leaf  */
928 
929         leaf = new_leaf(inode, &bh, 0);
930         if (!leaf)
931                 return -ENOSPC;
932         bn = bh->b_blocknr;
933 
934         gfs2_assert(sdp, dip->i_entries < BIT(16));
935         leaf->lf_entries = cpu_to_be16(dip->i_entries);
936 
937         /*  Copy dirents  */
938 
939         gfs2_buffer_copy_tail(bh, sizeof(struct gfs2_leaf), dibh,
940                              sizeof(struct gfs2_dinode));
941 
942         /*  Find last entry  */
943 
944         x = 0;
945         args.len = bh->b_size - sizeof(struct gfs2_dinode) +
946                    sizeof(struct gfs2_leaf);
947         args.name = bh->b_data;
948         dent = gfs2_dirent_scan(&dip->i_inode, bh->b_data, bh->b_size,
949                                 gfs2_dirent_last, &args, NULL);
950         if (!dent) {
951                 brelse(bh);
952                 brelse(dibh);
953                 return -EIO;
954         }
955         if (IS_ERR(dent)) {
956                 brelse(bh);
957                 brelse(dibh);
958                 return PTR_ERR(dent);
959         }
960 
961         /*  Adjust the last dirent's record length
962            (Remember that dent still points to the last entry.)  */
963 
964         dent->de_rec_len = cpu_to_be16(be16_to_cpu(dent->de_rec_len) +
965                 sizeof(struct gfs2_dinode) -
966                 sizeof(struct gfs2_leaf));
967 
968         brelse(bh);
969 
970         /*  We're done with the new leaf block, now setup the new
971             hash table.  */
972 
973         gfs2_trans_add_meta(dip->i_gl, dibh);
974         gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
975 
976         lp = (__be64 *)(dibh->b_data + sizeof(struct gfs2_dinode));
977 
978         for (x = sdp->sd_hash_ptrs; x--; lp++)
979                 *lp = cpu_to_be64(bn);
980 
981         i_size_write(inode, sdp->sd_sb.sb_bsize / 2);
982         gfs2_add_inode_blocks(&dip->i_inode, 1);
983         dip->i_diskflags |= GFS2_DIF_EXHASH;
984 
985         for (x = sdp->sd_hash_ptrs, y = -1; x; x >>= 1, y++) ;
986         dip->i_depth = y;
987 
988         gfs2_dinode_out(dip, dibh->b_data);
989 
990         brelse(dibh);
991 
992         return 0;
993 }
994 
995 /**
996  * dir_split_leaf - Split a leaf block into two
997  * @dip: The GFS2 inode
998  * @index:
999  * @leaf_no:
1000  *
1001  * Returns: 0 on success, error code on failure
1002  */
1003 
1004 static int dir_split_leaf(struct inode *inode, const struct qstr *name)
1005 {
1006         struct gfs2_inode *dip = GFS2_I(inode);
1007         struct buffer_head *nbh, *obh, *dibh;
1008         struct gfs2_leaf *nleaf, *oleaf;
1009         struct gfs2_dirent *dent = NULL, *prev = NULL, *next = NULL, *new;
1010         u32 start, len, half_len, divider;
1011         u64 bn, leaf_no;
1012         __be64 *lp;
1013         u32 index;
1014         int x, moved = 0;
1015         int error;
1016 
1017         index = name->hash >> (32 - dip->i_depth);
1018         error = get_leaf_nr(dip, index, &leaf_no);
1019         if (error)
1020                 return error;
1021 
1022         /*  Get the old leaf block  */
1023         error = get_leaf(dip, leaf_no, &obh);
1024         if (error)
1025                 return error;
1026 
1027         oleaf = (struct gfs2_leaf *)obh->b_data;
1028         if (dip->i_depth == be16_to_cpu(oleaf->lf_depth)) {
1029                 brelse(obh);
1030                 return 1; /* can't split */
1031         }
1032 
1033         gfs2_trans_add_meta(dip->i_gl, obh);
1034 
1035         nleaf = new_leaf(inode, &nbh, be16_to_cpu(oleaf->lf_depth) + 1);
1036         if (!nleaf) {
1037                 brelse(obh);
1038                 return -ENOSPC;
1039         }
1040         bn = nbh->b_blocknr;
1041 
1042         /*  Compute the start and len of leaf pointers in the hash table.  */
1043         len = BIT(dip->i_depth - be16_to_cpu(oleaf->lf_depth));
1044         half_len = len >> 1;
1045         if (!half_len) {
1046                 pr_warn("i_depth %u lf_depth %u index %u\n",
1047                         dip->i_depth, be16_to_cpu(oleaf->lf_depth), index);
1048                 gfs2_consist_inode(dip);
1049                 error = -EIO;
1050                 goto fail_brelse;
1051         }
1052 
1053         start = (index & ~(len - 1));
1054 
1055         /* Change the pointers.
1056            Don't bother distinguishing stuffed from non-stuffed.
1057            This code is complicated enough already. */
1058         lp = kmalloc_array(half_len, sizeof(__be64), GFP_NOFS);
1059         if (!lp) {
1060                 error = -ENOMEM;
1061                 goto fail_brelse;
1062         }
1063 
1064         /*  Change the pointers  */
1065         for (x = 0; x < half_len; x++)
1066                 lp[x] = cpu_to_be64(bn);
1067 
1068         gfs2_dir_hash_inval(dip);
1069 
1070         error = gfs2_dir_write_data(dip, (char *)lp, start * sizeof(u64),
1071                                     half_len * sizeof(u64));
1072         if (error != half_len * sizeof(u64)) {
1073                 if (error >= 0)
1074                         error = -EIO;
1075                 goto fail_lpfree;
1076         }
1077 
1078         kfree(lp);
1079 
1080         /*  Compute the divider  */
1081         divider = (start + half_len) << (32 - dip->i_depth);
1082 
1083         /*  Copy the entries  */
1084         dent = (struct gfs2_dirent *)(obh->b_data + sizeof(struct gfs2_leaf));
1085 
1086         do {
1087                 next = dent;
1088                 if (dirent_next(dip, obh, &next))
1089                         next = NULL;
1090 
1091                 if (!gfs2_dirent_sentinel(dent) &&
1092                     be32_to_cpu(dent->de_hash) < divider) {
1093                         struct qstr str;
1094                         void *ptr = ((char *)dent - obh->b_data) + nbh->b_data;
1095                         str.name = (char*)(dent+1);
1096                         str.len = be16_to_cpu(dent->de_name_len);
1097                         str.hash = be32_to_cpu(dent->de_hash);
1098                         new = gfs2_dirent_split_alloc(inode, nbh, &str, ptr);
1099                         if (IS_ERR(new)) {
1100                                 error = PTR_ERR(new);
1101                                 break;
1102                         }
1103 
1104                         new->de_inum = dent->de_inum; /* No endian worries */
1105                         new->de_type = dent->de_type; /* No endian worries */
1106                         be16_add_cpu(&nleaf->lf_entries, 1);
1107 
1108                         dirent_del(dip, obh, prev, dent);
1109 
1110                         if (!oleaf->lf_entries)
1111                                 gfs2_consist_inode(dip);
1112                         be16_add_cpu(&oleaf->lf_entries, -1);
1113 
1114                         if (!prev)
1115                                 prev = dent;
1116 
1117                         moved = 1;
1118                 } else {
1119                         prev = dent;
1120                 }
1121                 dent = next;
1122         } while (dent);
1123 
1124         oleaf->lf_depth = nleaf->lf_depth;
1125 
1126         error = gfs2_meta_inode_buffer(dip, &dibh);
1127         if (!gfs2_assert_withdraw(GFS2_SB(&dip->i_inode), !error)) {
1128                 gfs2_trans_add_meta(dip->i_gl, dibh);
1129                 gfs2_add_inode_blocks(&dip->i_inode, 1);
1130                 gfs2_dinode_out(dip, dibh->b_data);
1131                 brelse(dibh);
1132         }
1133 
1134         brelse(obh);
1135         brelse(nbh);
1136 
1137         return error;
1138 
1139 fail_lpfree:
1140         kfree(lp);
1141 
1142 fail_brelse:
1143         brelse(obh);
1144         brelse(nbh);
1145         return error;
1146 }
1147 
1148 /**
1149  * dir_double_exhash - Double size of ExHash table
1150  * @dip: The GFS2 dinode
1151  *
1152  * Returns: 0 on success, error code on failure
1153  */
1154 
1155 static int dir_double_exhash(struct gfs2_inode *dip)
1156 {
1157         struct buffer_head *dibh;
1158         u32 hsize;
1159         u32 hsize_bytes;
1160         __be64 *hc;
1161         __be64 *hc2, *h;
1162         int x;
1163         int error = 0;
1164 
1165         hsize = BIT(dip->i_depth);
1166         hsize_bytes = hsize * sizeof(__be64);
1167 
1168         hc = gfs2_dir_get_hash_table(dip);
1169         if (IS_ERR(hc))
1170                 return PTR_ERR(hc);
1171 
1172         hc2 = kmalloc_array(hsize_bytes, 2, GFP_NOFS | __GFP_NOWARN);
1173         if (hc2 == NULL)
1174                 hc2 = __vmalloc(hsize_bytes * 2, GFP_NOFS, PAGE_KERNEL);
1175 
1176         if (!hc2)
1177                 return -ENOMEM;
1178 
1179         h = hc2;
1180         error = gfs2_meta_inode_buffer(dip, &dibh);
1181         if (error)
1182                 goto out_kfree;
1183 
1184         for (x = 0; x < hsize; x++) {
1185                 *h++ = *hc;
1186                 *h++ = *hc;
1187                 hc++;
1188         }
1189 
1190         error = gfs2_dir_write_data(dip, (char *)hc2, 0, hsize_bytes * 2);
1191         if (error != (hsize_bytes * 2))
1192                 goto fail;
1193 
1194         gfs2_dir_hash_inval(dip);
1195         dip->i_hash_cache = hc2;
1196         dip->i_depth++;
1197         gfs2_dinode_out(dip, dibh->b_data);
1198         brelse(dibh);
1199         return 0;
1200 
1201 fail:
1202         /* Replace original hash table & size */
1203         gfs2_dir_write_data(dip, (char *)hc, 0, hsize_bytes);
1204         i_size_write(&dip->i_inode, hsize_bytes);
1205         gfs2_dinode_out(dip, dibh->b_data);
1206         brelse(dibh);
1207 out_kfree:
1208         kvfree(hc2);
1209         return error;
1210 }
1211 
1212 /**
1213  * compare_dents - compare directory entries by hash value
1214  * @a: first dent
1215  * @b: second dent
1216  *
1217  * When comparing the hash entries of @a to @b:
1218  *   gt: returns 1
1219  *   lt: returns -1
1220  *   eq: returns 0
1221  */
1222 
1223 static int compare_dents(const void *a, const void *b)
1224 {
1225         const struct gfs2_dirent *dent_a, *dent_b;
1226         u32 hash_a, hash_b;
1227         int ret = 0;
1228 
1229         dent_a = *(const struct gfs2_dirent **)a;
1230         hash_a = dent_a->de_cookie;
1231 
1232         dent_b = *(const struct gfs2_dirent **)b;
1233         hash_b = dent_b->de_cookie;
1234 
1235         if (hash_a > hash_b)
1236                 ret = 1;
1237         else if (hash_a < hash_b)
1238                 ret = -1;
1239         else {
1240                 unsigned int len_a = be16_to_cpu(dent_a->de_name_len);
1241                 unsigned int len_b = be16_to_cpu(dent_b->de_name_len);
1242 
1243                 if (len_a > len_b)
1244                         ret = 1;
1245                 else if (len_a < len_b)
1246                         ret = -1;
1247                 else
1248                         ret = memcmp(dent_a + 1, dent_b + 1, len_a);
1249         }
1250 
1251         return ret;
1252 }
1253 
1254 /**
1255  * do_filldir_main - read out directory entries
1256  * @dip: The GFS2 inode
1257  * @ctx: what to feed the entries to
1258  * @darr: an array of struct gfs2_dirent pointers to read
1259  * @entries: the number of entries in darr
1260  * @copied: pointer to int that's non-zero if a entry has been copied out
1261  *
1262  * Jump through some hoops to make sure that if there are hash collsions,
1263  * they are read out at the beginning of a buffer.  We want to minimize
1264  * the possibility that they will fall into different readdir buffers or
1265  * that someone will want to seek to that location.
1266  *
1267  * Returns: errno, >0 if the actor tells you to stop
1268  */
1269 
1270 static int do_filldir_main(struct gfs2_inode *dip, struct dir_context *ctx,
1271                            struct gfs2_dirent **darr, u32 entries,
1272                            u32 sort_start, int *copied)
1273 {
1274         const struct gfs2_dirent *dent, *dent_next;
1275         u64 off, off_next;
1276         unsigned int x, y;
1277         int run = 0;
1278 
1279         if (sort_start < entries)
1280                 sort(&darr[sort_start], entries - sort_start,
1281                      sizeof(struct gfs2_dirent *), compare_dents, NULL);
1282 
1283         dent_next = darr[0];
1284         off_next = dent_next->de_cookie;
1285 
1286         for (x = 0, y = 1; x < entries; x++, y++) {
1287                 dent = dent_next;
1288                 off = off_next;
1289 
1290                 if (y < entries) {
1291                         dent_next = darr[y];
1292                         off_next = dent_next->de_cookie;
1293 
1294                         if (off < ctx->pos)
1295                                 continue;
1296                         ctx->pos = off;
1297 
1298                         if (off_next == off) {
1299                                 if (*copied && !run)
1300                                         return 1;
1301                                 run = 1;
1302                         } else
1303                                 run = 0;
1304                 } else {
1305                         if (off < ctx->pos)
1306                                 continue;
1307                         ctx->pos = off;
1308                 }
1309 
1310                 if (!dir_emit(ctx, (const char *)(dent + 1),
1311                                 be16_to_cpu(dent->de_name_len),
1312                                 be64_to_cpu(dent->de_inum.no_addr),
1313                                 be16_to_cpu(dent->de_type)))
1314                         return 1;
1315 
1316                 *copied = 1;
1317         }
1318 
1319         /* Increment the ctx->pos by one, so the next time we come into the
1320            do_filldir fxn, we get the next entry instead of the last one in the
1321            current leaf */
1322 
1323         ctx->pos++;
1324 
1325         return 0;
1326 }
1327 
1328 static void *gfs2_alloc_sort_buffer(unsigned size)
1329 {
1330         void *ptr = NULL;
1331 
1332         if (size < KMALLOC_MAX_SIZE)
1333                 ptr = kmalloc(size, GFP_NOFS | __GFP_NOWARN);
1334         if (!ptr)
1335                 ptr = __vmalloc(size, GFP_NOFS, PAGE_KERNEL);
1336         return ptr;
1337 }
1338 
1339 
1340 static int gfs2_set_cookies(struct gfs2_sbd *sdp, struct buffer_head *bh,
1341                             unsigned leaf_nr, struct gfs2_dirent **darr,
1342                             unsigned entries)
1343 {
1344         int sort_id = -1;
1345         int i;
1346         
1347         for (i = 0; i < entries; i++) {
1348                 unsigned offset;
1349 
1350                 darr[i]->de_cookie = be32_to_cpu(darr[i]->de_hash);
1351                 darr[i]->de_cookie = gfs2_disk_hash2offset(darr[i]->de_cookie);
1352 
1353                 if (!sdp->sd_args.ar_loccookie)
1354                         continue;
1355                 offset = (char *)(darr[i]) -
1356                          (bh->b_data + gfs2_dirent_offset(bh->b_data));
1357                 offset /= GFS2_MIN_DIRENT_SIZE;
1358                 offset += leaf_nr * sdp->sd_max_dents_per_leaf;
1359                 if (offset >= GFS2_USE_HASH_FLAG ||
1360                     leaf_nr >= GFS2_USE_HASH_FLAG) {
1361                         darr[i]->de_cookie |= GFS2_USE_HASH_FLAG;
1362                         if (sort_id < 0)
1363                                 sort_id = i;
1364                         continue;
1365                 }
1366                 darr[i]->de_cookie &= GFS2_HASH_INDEX_MASK;
1367                 darr[i]->de_cookie |= offset;
1368         }
1369         return sort_id;
1370 }       
1371 
1372 
1373 static int gfs2_dir_read_leaf(struct inode *inode, struct dir_context *ctx,
1374                               int *copied, unsigned *depth,
1375                               u64 leaf_no)
1376 {
1377         struct gfs2_inode *ip = GFS2_I(inode);
1378         struct gfs2_sbd *sdp = GFS2_SB(inode);
1379         struct buffer_head *bh;
1380         struct gfs2_leaf *lf;
1381         unsigned entries = 0, entries2 = 0;
1382         unsigned leaves = 0, leaf = 0, offset, sort_offset;
1383         struct gfs2_dirent **darr, *dent;
1384         struct dirent_gather g;
1385         struct buffer_head **larr;
1386         int error, i, need_sort = 0, sort_id;
1387         u64 lfn = leaf_no;
1388 
1389         do {
1390                 error = get_leaf(ip, lfn, &bh);
1391                 if (error)
1392                         goto out;
1393                 lf = (struct gfs2_leaf *)bh->b_data;
1394                 if (leaves == 0)
1395                         *depth = be16_to_cpu(lf->lf_depth);
1396                 entries += be16_to_cpu(lf->lf_entries);
1397                 leaves++;
1398                 lfn = be64_to_cpu(lf->lf_next);
1399                 brelse(bh);
1400         } while(lfn);
1401 
1402         if (*depth < GFS2_DIR_MAX_DEPTH || !sdp->sd_args.ar_loccookie) {
1403                 need_sort = 1;
1404                 sort_offset = 0;
1405         }
1406 
1407         if (!entries)
1408                 return 0;
1409 
1410         error = -ENOMEM;
1411         /*
1412          * The extra 99 entries are not normally used, but are a buffer
1413          * zone in case the number of entries in the leaf is corrupt.
1414          * 99 is the maximum number of entries that can fit in a single
1415          * leaf block.
1416          */
1417         larr = gfs2_alloc_sort_buffer((leaves + entries + 99) * sizeof(void *));
1418         if (!larr)
1419                 goto out;
1420         darr = (struct gfs2_dirent **)(larr + leaves);
1421         g.pdent = (const struct gfs2_dirent **)darr;
1422         g.offset = 0;
1423         lfn = leaf_no;
1424 
1425         do {
1426                 error = get_leaf(ip, lfn, &bh);
1427                 if (error)
1428                         goto out_free;
1429                 lf = (struct gfs2_leaf *)bh->b_data;
1430                 lfn = be64_to_cpu(lf->lf_next);
1431                 if (lf->lf_entries) {
1432                         offset = g.offset;
1433                         entries2 += be16_to_cpu(lf->lf_entries);
1434                         dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size,
1435                                                 gfs2_dirent_gather, NULL, &g);
1436                         error = PTR_ERR(dent);
1437                         if (IS_ERR(dent))
1438                                 goto out_free;
1439                         if (entries2 != g.offset) {
1440                                 fs_warn(sdp, "Number of entries corrupt in dir "
1441                                                 "leaf %llu, entries2 (%u) != "
1442                                                 "g.offset (%u)\n",
1443                                         (unsigned long long)bh->b_blocknr,
1444                                         entries2, g.offset);
1445                                 gfs2_consist_inode(ip);
1446                                 error = -EIO;
1447                                 goto out_free;
1448                         }
1449                         error = 0;
1450                         sort_id = gfs2_set_cookies(sdp, bh, leaf, &darr[offset],
1451                                                    be16_to_cpu(lf->lf_entries));
1452                         if (!need_sort && sort_id >= 0) {
1453                                 need_sort = 1;
1454                                 sort_offset = offset + sort_id;
1455                         }
1456                         larr[leaf++] = bh;
1457                 } else {
1458                         larr[leaf++] = NULL;
1459                         brelse(bh);
1460                 }
1461         } while(lfn);
1462 
1463         BUG_ON(entries2 != entries);
1464         error = do_filldir_main(ip, ctx, darr, entries, need_sort ?
1465                                 sort_offset : entries, copied);
1466 out_free:
1467         for(i = 0; i < leaf; i++)
1468                 if (larr[i])
1469                         brelse(larr[i]);
1470         kvfree(larr);
1471 out:
1472         return error;
1473 }
1474 
1475 /**
1476  * gfs2_dir_readahead - Issue read-ahead requests for leaf blocks.
1477  *
1478  * Note: we can't calculate each index like dir_e_read can because we don't
1479  * have the leaf, and therefore we don't have the depth, and therefore we
1480  * don't have the length. So we have to just read enough ahead to make up
1481  * for the loss of information.
1482  */
1483 static void gfs2_dir_readahead(struct inode *inode, unsigned hsize, u32 index,
1484                                struct file_ra_state *f_ra)
1485 {
1486         struct gfs2_inode *ip = GFS2_I(inode);
1487         struct gfs2_glock *gl = ip->i_gl;
1488         struct buffer_head *bh;
1489         u64 blocknr = 0, last;
1490         unsigned count;
1491 
1492         /* First check if we've already read-ahead for the whole range. */
1493         if (index + MAX_RA_BLOCKS < f_ra->start)
1494                 return;
1495 
1496         f_ra->start = max((pgoff_t)index, f_ra->start);
1497         for (count = 0; count < MAX_RA_BLOCKS; count++) {
1498                 if (f_ra->start >= hsize) /* if exceeded the hash table */
1499                         break;
1500 
1501                 last = blocknr;
1502                 blocknr = be64_to_cpu(ip->i_hash_cache[f_ra->start]);
1503                 f_ra->start++;
1504                 if (blocknr == last)
1505                         continue;
1506 
1507                 bh = gfs2_getbuf(gl, blocknr, 1);
1508                 if (trylock_buffer(bh)) {
1509                         if (buffer_uptodate(bh)) {
1510                                 unlock_buffer(bh);
1511                                 brelse(bh);
1512                                 continue;
1513                         }
1514                         bh->b_end_io = end_buffer_read_sync;
1515                         submit_bh(REQ_OP_READ,
1516                                   REQ_RAHEAD | REQ_META | REQ_PRIO,
1517                                   bh);
1518                         continue;
1519                 }
1520                 brelse(bh);
1521         }
1522 }
1523 
1524 /**
1525  * dir_e_read - Reads the entries from a directory into a filldir buffer
1526  * @dip: dinode pointer
1527  * @ctx: actor to feed the entries to
1528  *
1529  * Returns: errno
1530  */
1531 
1532 static int dir_e_read(struct inode *inode, struct dir_context *ctx,
1533                       struct file_ra_state *f_ra)
1534 {
1535         struct gfs2_inode *dip = GFS2_I(inode);
1536         u32 hsize, len = 0;
1537         u32 hash, index;
1538         __be64 *lp;
1539         int copied = 0;
1540         int error = 0;
1541         unsigned depth = 0;
1542 
1543         hsize = BIT(dip->i_depth);
1544         hash = gfs2_dir_offset2hash(ctx->pos);
1545         index = hash >> (32 - dip->i_depth);
1546 
1547         if (dip->i_hash_cache == NULL)
1548                 f_ra->start = 0;
1549         lp = gfs2_dir_get_hash_table(dip);
1550         if (IS_ERR(lp))
1551                 return PTR_ERR(lp);
1552 
1553         gfs2_dir_readahead(inode, hsize, index, f_ra);
1554 
1555         while (index < hsize) {
1556                 error = gfs2_dir_read_leaf(inode, ctx,
1557                                            &copied, &depth,
1558                                            be64_to_cpu(lp[index]));
1559                 if (error)
1560                         break;
1561 
1562                 len = BIT(dip->i_depth - depth);
1563                 index = (index & ~(len - 1)) + len;
1564         }
1565 
1566         if (error > 0)
1567                 error = 0;
1568         return error;
1569 }
1570 
1571 int gfs2_dir_read(struct inode *inode, struct dir_context *ctx,
1572                   struct file_ra_state *f_ra)
1573 {
1574         struct gfs2_inode *dip = GFS2_I(inode);
1575         struct gfs2_sbd *sdp = GFS2_SB(inode);
1576         struct dirent_gather g;
1577         struct gfs2_dirent **darr, *dent;
1578         struct buffer_head *dibh;
1579         int copied = 0;
1580         int error;
1581 
1582         if (!dip->i_entries)
1583                 return 0;
1584 
1585         if (dip->i_diskflags & GFS2_DIF_EXHASH)
1586                 return dir_e_read(inode, ctx, f_ra);
1587 
1588         if (!gfs2_is_stuffed(dip)) {
1589                 gfs2_consist_inode(dip);
1590                 return -EIO;
1591         }
1592 
1593         error = gfs2_meta_inode_buffer(dip, &dibh);
1594         if (error)
1595                 return error;
1596 
1597         error = -ENOMEM;
1598         /* 96 is max number of dirents which can be stuffed into an inode */
1599         darr = kmalloc_array(96, sizeof(struct gfs2_dirent *), GFP_NOFS);
1600         if (darr) {
1601                 g.pdent = (const struct gfs2_dirent **)darr;
1602                 g.offset = 0;
1603                 dent = gfs2_dirent_scan(inode, dibh->b_data, dibh->b_size,
1604                                         gfs2_dirent_gather, NULL, &g);
1605                 if (IS_ERR(dent)) {
1606                         error = PTR_ERR(dent);
1607                         goto out;
1608                 }
1609                 if (dip->i_entries != g.offset) {
1610                         fs_warn(sdp, "Number of entries corrupt in dir %llu, "
1611                                 "ip->i_entries (%u) != g.offset (%u)\n",
1612                                 (unsigned long long)dip->i_no_addr,
1613                                 dip->i_entries,
1614                                 g.offset);
1615                         gfs2_consist_inode(dip);
1616                         error = -EIO;
1617                         goto out;
1618                 }
1619                 gfs2_set_cookies(sdp, dibh, 0, darr, dip->i_entries);
1620                 error = do_filldir_main(dip, ctx, darr,
1621                                         dip->i_entries, 0, &copied);
1622 out:
1623                 kfree(darr);
1624         }
1625 
1626         if (error > 0)
1627                 error = 0;
1628 
1629         brelse(dibh);
1630 
1631         return error;
1632 }
1633 
1634 /**
1635  * gfs2_dir_search - Search a directory
1636  * @dip: The GFS2 dir inode
1637  * @name: The name we are looking up
1638  * @fail_on_exist: Fail if the name exists rather than looking it up
1639  *
1640  * This routine searches a directory for a file or another directory.
1641  * Assumes a glock is held on dip.
1642  *
1643  * Returns: errno
1644  */
1645 
1646 struct inode *gfs2_dir_search(struct inode *dir, const struct qstr *name,
1647                               bool fail_on_exist)
1648 {
1649         struct buffer_head *bh;
1650         struct gfs2_dirent *dent;
1651         u64 addr, formal_ino;
1652         u16 dtype;
1653 
1654         dent = gfs2_dirent_search(dir, name, gfs2_dirent_find, &bh);
1655         if (dent) {
1656                 struct inode *inode;
1657                 u16 rahead;
1658 
1659                 if (IS_ERR(dent))
1660                         return ERR_CAST(dent);
1661                 dtype = be16_to_cpu(dent->de_type);
1662                 rahead = be16_to_cpu(dent->de_rahead);
1663                 addr = be64_to_cpu(dent->de_inum.no_addr);
1664                 formal_ino = be64_to_cpu(dent->de_inum.no_formal_ino);
1665                 brelse(bh);
1666                 if (fail_on_exist)
1667                         return ERR_PTR(-EEXIST);
1668                 inode = gfs2_inode_lookup(dir->i_sb, dtype, addr, formal_ino,
1669                                           GFS2_BLKST_FREE /* ignore */);
1670                 if (!IS_ERR(inode))
1671                         GFS2_I(inode)->i_rahead = rahead;
1672                 return inode;
1673         }
1674         return ERR_PTR(-ENOENT);
1675 }
1676 
1677 int gfs2_dir_check(struct inode *dir, const struct qstr *name,
1678                    const struct gfs2_inode *ip)
1679 {
1680         struct buffer_head *bh;
1681         struct gfs2_dirent *dent;
1682         int ret = -ENOENT;
1683 
1684         dent = gfs2_dirent_search(dir, name, gfs2_dirent_find, &bh);
1685         if (dent) {
1686                 if (IS_ERR(dent))
1687                         return PTR_ERR(dent);
1688                 if (ip) {
1689                         if (be64_to_cpu(dent->de_inum.no_addr) != ip->i_no_addr)
1690                                 goto out;
1691                         if (be64_to_cpu(dent->de_inum.no_formal_ino) !=
1692                             ip->i_no_formal_ino)
1693                                 goto out;
1694                         if (unlikely(IF2DT(ip->i_inode.i_mode) !=
1695                             be16_to_cpu(dent->de_type))) {
1696                                 gfs2_consist_inode(GFS2_I(dir));
1697                                 ret = -EIO;
1698                                 goto out;
1699                         }
1700                 }
1701                 ret = 0;
1702 out:
1703                 brelse(bh);
1704         }
1705         return ret;
1706 }
1707 
1708 /**
1709  * dir_new_leaf - Add a new leaf onto hash chain
1710  * @inode: The directory
1711  * @name: The name we are adding
1712  *
1713  * This adds a new dir leaf onto an existing leaf when there is not
1714  * enough space to add a new dir entry. This is a last resort after
1715  * we've expanded the hash table to max size and also split existing
1716  * leaf blocks, so it will only occur for very large directories.
1717  *
1718  * The dist parameter is set to 1 for leaf blocks directly attached
1719  * to the hash table, 2 for one layer of indirection, 3 for two layers
1720  * etc. We are thus able to tell the difference between an old leaf
1721  * with dist set to zero (i.e. "don't know") and a new one where we
1722  * set this information for debug/fsck purposes.
1723  *
1724  * Returns: 0 on success, or -ve on error
1725  */
1726 
1727 static int dir_new_leaf(struct inode *inode, const struct qstr *name)
1728 {
1729         struct buffer_head *bh, *obh;
1730         struct gfs2_inode *ip = GFS2_I(inode);
1731         struct gfs2_leaf *leaf, *oleaf;
1732         u32 dist = 1;
1733         int error;
1734         u32 index;
1735         u64 bn;
1736 
1737         index = name->hash >> (32 - ip->i_depth);
1738         error = get_first_leaf(ip, index, &obh);
1739         if (error)
1740                 return error;
1741         do {
1742                 dist++;
1743                 oleaf = (struct gfs2_leaf *)obh->b_data;
1744                 bn = be64_to_cpu(oleaf->lf_next);
1745                 if (!bn)
1746                         break;
1747                 brelse(obh);
1748                 error = get_leaf(ip, bn, &obh);
1749                 if (error)
1750                         return error;
1751         } while(1);
1752 
1753         gfs2_trans_add_meta(ip->i_gl, obh);
1754 
1755         leaf = new_leaf(inode, &bh, be16_to_cpu(oleaf->lf_depth));
1756         if (!leaf) {
1757                 brelse(obh);
1758                 return -ENOSPC;
1759         }
1760         leaf->lf_dist = cpu_to_be32(dist);
1761         oleaf->lf_next = cpu_to_be64(bh->b_blocknr);
1762         brelse(bh);
1763         brelse(obh);
1764 
1765         error = gfs2_meta_inode_buffer(ip, &bh);
1766         if (error)
1767                 return error;
1768         gfs2_trans_add_meta(ip->i_gl, bh);
1769         gfs2_add_inode_blocks(&ip->i_inode, 1);
1770         gfs2_dinode_out(ip, bh->b_data);
1771         brelse(bh);
1772         return 0;
1773 }
1774 
1775 static u16 gfs2_inode_ra_len(const struct gfs2_inode *ip)
1776 {
1777         u64 where = ip->i_no_addr + 1;
1778         if (ip->i_eattr == where)
1779                 return 1;
1780         return 0;
1781 }
1782 
1783 /**
1784  * gfs2_dir_add - Add new filename into directory
1785  * @inode: The directory inode
1786  * @name: The new name
1787  * @nip: The GFS2 inode to be linked in to the directory
1788  * @da: The directory addition info
1789  *
1790  * If the call to gfs2_diradd_alloc_required resulted in there being
1791  * no need to allocate any new directory blocks, then it will contain
1792  * a pointer to the directory entry and the bh in which it resides. We
1793  * can use that without having to repeat the search. If there was no
1794  * free space, then we must now create more space.
1795  *
1796  * Returns: 0 on success, error code on failure
1797  */
1798 
1799 int gfs2_dir_add(struct inode *inode, const struct qstr *name,
1800                  const struct gfs2_inode *nip, struct gfs2_diradd *da)
1801 {
1802         struct gfs2_inode *ip = GFS2_I(inode);
1803         struct buffer_head *bh = da->bh;
1804         struct gfs2_dirent *dent = da->dent;
1805         struct timespec64 tv;
1806         struct gfs2_leaf *leaf;
1807         int error;
1808 
1809         while(1) {
1810                 if (da->bh == NULL) {
1811                         dent = gfs2_dirent_search(inode, name,
1812                                                   gfs2_dirent_find_space, &bh);
1813                 }
1814                 if (dent) {
1815                         if (IS_ERR(dent))
1816                                 return PTR_ERR(dent);
1817                         dent = gfs2_init_dirent(inode, dent, name, bh);
1818                         gfs2_inum_out(nip, dent);
1819                         dent->de_type = cpu_to_be16(IF2DT(nip->i_inode.i_mode));
1820                         dent->de_rahead = cpu_to_be16(gfs2_inode_ra_len(nip));
1821                         tv = current_time(&ip->i_inode);
1822                         if (ip->i_diskflags & GFS2_DIF_EXHASH) {
1823                                 leaf = (struct gfs2_leaf *)bh->b_data;
1824                                 be16_add_cpu(&leaf->lf_entries, 1);
1825                                 leaf->lf_nsec = cpu_to_be32(tv.tv_nsec);
1826                                 leaf->lf_sec = cpu_to_be64(tv.tv_sec);
1827                         }
1828                         da->dent = NULL;
1829                         da->bh = NULL;
1830                         brelse(bh);
1831                         ip->i_entries++;
1832                         ip->i_inode.i_mtime = ip->i_inode.i_ctime = tv;
1833                         if (S_ISDIR(nip->i_inode.i_mode))
1834                                 inc_nlink(&ip->i_inode);
1835                         mark_inode_dirty(inode);
1836                         error = 0;
1837                         break;
1838                 }
1839                 if (!(ip->i_diskflags & GFS2_DIF_EXHASH)) {
1840                         error = dir_make_exhash(inode);
1841                         if (error)
1842                                 break;
1843                         continue;
1844                 }
1845                 error = dir_split_leaf(inode, name);
1846                 if (error == 0)
1847                         continue;
1848                 if (error < 0)
1849                         break;
1850                 if (ip->i_depth < GFS2_DIR_MAX_DEPTH) {
1851                         error = dir_double_exhash(ip);
1852                         if (error)
1853                                 break;
1854                         error = dir_split_leaf(inode, name);
1855                         if (error < 0)
1856                                 break;
1857                         if (error == 0)
1858                                 continue;
1859                 }
1860                 error = dir_new_leaf(inode, name);
1861                 if (!error)
1862                         continue;
1863                 error = -ENOSPC;
1864                 break;
1865         }
1866         return error;
1867 }
1868 
1869 
1870 /**
1871  * gfs2_dir_del - Delete a directory entry
1872  * @dip: The GFS2 inode
1873  * @filename: The filename
1874  *
1875  * Returns: 0 on success, error code on failure
1876  */
1877 
1878 int gfs2_dir_del(struct gfs2_inode *dip, const struct dentry *dentry)
1879 {
1880         const struct qstr *name = &dentry->d_name;
1881         struct gfs2_dirent *dent, *prev = NULL;
1882         struct buffer_head *bh;
1883         struct timespec64 tv = current_time(&dip->i_inode);
1884 
1885         /* Returns _either_ the entry (if its first in block) or the
1886            previous entry otherwise */
1887         dent = gfs2_dirent_search(&dip->i_inode, name, gfs2_dirent_prev, &bh);
1888         if (!dent) {
1889                 gfs2_consist_inode(dip);
1890                 return -EIO;
1891         }
1892         if (IS_ERR(dent)) {
1893                 gfs2_consist_inode(dip);
1894                 return PTR_ERR(dent);
1895         }
1896         /* If not first in block, adjust pointers accordingly */
1897         if (gfs2_dirent_find(dent, name, NULL) == 0) {
1898                 prev = dent;
1899                 dent = (struct gfs2_dirent *)((char *)dent + be16_to_cpu(prev->de_rec_len));
1900         }
1901 
1902         dirent_del(dip, bh, prev, dent);
1903         if (dip->i_diskflags & GFS2_DIF_EXHASH) {
1904                 struct gfs2_leaf *leaf = (struct gfs2_leaf *)bh->b_data;
1905                 u16 entries = be16_to_cpu(leaf->lf_entries);
1906                 if (!entries)
1907                         gfs2_consist_inode(dip);
1908                 leaf->lf_entries = cpu_to_be16(--entries);
1909                 leaf->lf_nsec = cpu_to_be32(tv.tv_nsec);
1910                 leaf->lf_sec = cpu_to_be64(tv.tv_sec);
1911         }
1912         brelse(bh);
1913 
1914         if (!dip->i_entries)
1915                 gfs2_consist_inode(dip);
1916         dip->i_entries--;
1917         dip->i_inode.i_mtime = dip->i_inode.i_ctime = tv;
1918         if (d_is_dir(dentry))
1919                 drop_nlink(&dip->i_inode);
1920         mark_inode_dirty(&dip->i_inode);
1921 
1922         return 0;
1923 }
1924 
1925 /**
1926  * gfs2_dir_mvino - Change inode number of directory entry
1927  * @dip: The GFS2 inode
1928  * @filename:
1929  * @new_inode:
1930  *
1931  * This routine changes the inode number of a directory entry.  It's used
1932  * by rename to change ".." when a directory is moved.
1933  * Assumes a glock is held on dvp.
1934  *
1935  * Returns: errno
1936  */
1937 
1938 int gfs2_dir_mvino(struct gfs2_inode *dip, const struct qstr *filename,
1939                    const struct gfs2_inode *nip, unsigned int new_type)
1940 {
1941         struct buffer_head *bh;
1942         struct gfs2_dirent *dent;
1943 
1944         dent = gfs2_dirent_search(&dip->i_inode, filename, gfs2_dirent_find, &bh);
1945         if (!dent) {
1946                 gfs2_consist_inode(dip);
1947                 return -EIO;
1948         }
1949         if (IS_ERR(dent))
1950                 return PTR_ERR(dent);
1951 
1952         gfs2_trans_add_meta(dip->i_gl, bh);
1953         gfs2_inum_out(nip, dent);
1954         dent->de_type = cpu_to_be16(new_type);
1955         brelse(bh);
1956 
1957         dip->i_inode.i_mtime = dip->i_inode.i_ctime = current_time(&dip->i_inode);
1958         mark_inode_dirty_sync(&dip->i_inode);
1959         return 0;
1960 }
1961 
1962 /**
1963  * leaf_dealloc - Deallocate a directory leaf
1964  * @dip: the directory
1965  * @index: the hash table offset in the directory
1966  * @len: the number of pointers to this leaf
1967  * @leaf_no: the leaf number
1968  * @leaf_bh: buffer_head for the starting leaf
1969  * last_dealloc: 1 if this is the final dealloc for the leaf, else 0
1970  *
1971  * Returns: errno
1972  */
1973 
1974 static int leaf_dealloc(struct gfs2_inode *dip, u32 index, u32 len,
1975                         u64 leaf_no, struct buffer_head *leaf_bh,
1976                         int last_dealloc)
1977 {
1978         struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
1979         struct gfs2_leaf *tmp_leaf;
1980         struct gfs2_rgrp_list rlist;
1981         struct buffer_head *bh, *dibh;
1982         u64 blk, nblk;
1983         unsigned int rg_blocks = 0, l_blocks = 0;
1984         char *ht;
1985         unsigned int x, size = len * sizeof(u64);
1986         int error;
1987 
1988         error = gfs2_rindex_update(sdp);
1989         if (error)
1990                 return error;
1991 
1992         memset(&rlist, 0, sizeof(struct gfs2_rgrp_list));
1993 
1994         ht = kzalloc(size, GFP_NOFS | __GFP_NOWARN);
1995         if (ht == NULL)
1996                 ht = __vmalloc(size, GFP_NOFS | __GFP_NOWARN | __GFP_ZERO,
1997                                PAGE_KERNEL);
1998         if (!ht)
1999                 return -ENOMEM;
2000 
2001         error = gfs2_quota_hold(dip, NO_UID_QUOTA_CHANGE, NO_GID_QUOTA_CHANGE);
2002         if (error)
2003                 goto out;
2004 
2005         /*  Count the number of leaves  */
2006         bh = leaf_bh;
2007 
2008         for (blk = leaf_no; blk; blk = nblk) {
2009                 if (blk != leaf_no) {
2010                         error = get_leaf(dip, blk, &bh);
2011                         if (error)
2012                                 goto out_rlist;
2013                 }
2014                 tmp_leaf = (struct gfs2_leaf *)bh->b_data;
2015                 nblk = be64_to_cpu(tmp_leaf->lf_next);
2016                 if (blk != leaf_no)
2017                         brelse(bh);
2018 
2019                 gfs2_rlist_add(dip, &rlist, blk);
2020                 l_blocks++;
2021         }
2022 
2023         gfs2_rlist_alloc(&rlist, LM_ST_EXCLUSIVE);
2024 
2025         for (x = 0; x < rlist.rl_rgrps; x++) {
2026                 struct gfs2_rgrpd *rgd = gfs2_glock2rgrp(rlist.rl_ghs[x].gh_gl);
2027 
2028                 rg_blocks += rgd->rd_length;
2029         }
2030 
2031         error = gfs2_glock_nq_m(rlist.rl_rgrps, rlist.rl_ghs);
2032         if (error)
2033                 goto out_rlist;
2034 
2035         error = gfs2_trans_begin(sdp,
2036                         rg_blocks + (DIV_ROUND_UP(size, sdp->sd_jbsize) + 1) +
2037                         RES_DINODE + RES_STATFS + RES_QUOTA, l_blocks);
2038         if (error)
2039                 goto out_rg_gunlock;
2040 
2041         bh = leaf_bh;
2042 
2043         for (blk = leaf_no; blk; blk = nblk) {
2044                 if (blk != leaf_no) {
2045                         error = get_leaf(dip, blk, &bh);
2046                         if (error)
2047                                 goto out_end_trans;
2048                 }
2049                 tmp_leaf = (struct gfs2_leaf *)bh->b_data;
2050                 nblk = be64_to_cpu(tmp_leaf->lf_next);
2051                 if (blk != leaf_no)
2052                         brelse(bh);
2053 
2054                 gfs2_free_meta(dip, blk, 1);
2055                 gfs2_add_inode_blocks(&dip->i_inode, -1);
2056         }
2057 
2058         error = gfs2_dir_write_data(dip, ht, index * sizeof(u64), size);
2059         if (error != size) {
2060                 if (error >= 0)
2061                         error = -EIO;
2062                 goto out_end_trans;
2063         }
2064 
2065         error = gfs2_meta_inode_buffer(dip, &dibh);
2066         if (error)
2067                 goto out_end_trans;
2068 
2069         gfs2_trans_add_meta(dip->i_gl, dibh);
2070         /* On the last dealloc, make this a regular file in case we crash.
2071            (We don't want to free these blocks a second time.)  */
2072         if (last_dealloc)
2073                 dip->i_inode.i_mode = S_IFREG;
2074         gfs2_dinode_out(dip, dibh->b_data);
2075         brelse(dibh);
2076 
2077 out_end_trans:
2078         gfs2_trans_end(sdp);
2079 out_rg_gunlock:
2080         gfs2_glock_dq_m(rlist.rl_rgrps, rlist.rl_ghs);
2081 out_rlist:
2082         gfs2_rlist_free(&rlist);
2083         gfs2_quota_unhold(dip);
2084 out:
2085         kvfree(ht);
2086         return error;
2087 }
2088 
2089 /**
2090  * gfs2_dir_exhash_dealloc - free all the leaf blocks in a directory
2091  * @dip: the directory
2092  *
2093  * Dealloc all on-disk directory leaves to FREEMETA state
2094  * Change on-disk inode type to "regular file"
2095  *
2096  * Returns: errno
2097  */
2098 
2099 int gfs2_dir_exhash_dealloc(struct gfs2_inode *dip)
2100 {
2101         struct buffer_head *bh;
2102         struct gfs2_leaf *leaf;
2103         u32 hsize, len;
2104         u32 index = 0, next_index;
2105         __be64 *lp;
2106         u64 leaf_no;
2107         int error = 0, last;
2108 
2109         hsize = BIT(dip->i_depth);
2110 
2111         lp = gfs2_dir_get_hash_table(dip);
2112         if (IS_ERR(lp))
2113                 return PTR_ERR(lp);
2114 
2115         while (index < hsize) {
2116                 leaf_no = be64_to_cpu(lp[index]);
2117                 if (leaf_no) {
2118                         error = get_leaf(dip, leaf_no, &bh);
2119                         if (error)
2120                                 goto out;
2121                         leaf = (struct gfs2_leaf *)bh->b_data;
2122                         len = BIT(dip->i_depth - be16_to_cpu(leaf->lf_depth));
2123 
2124                         next_index = (index & ~(len - 1)) + len;
2125                         last = ((next_index >= hsize) ? 1 : 0);
2126                         error = leaf_dealloc(dip, index, len, leaf_no, bh,
2127                                              last);
2128                         brelse(bh);
2129                         if (error)
2130                                 goto out;
2131                         index = next_index;
2132                 } else
2133                         index++;
2134         }
2135 
2136         if (index != hsize) {
2137                 gfs2_consist_inode(dip);
2138                 error = -EIO;
2139         }
2140 
2141 out:
2142 
2143         return error;
2144 }
2145 
2146 /**
2147  * gfs2_diradd_alloc_required - find if adding entry will require an allocation
2148  * @ip: the file being written to
2149  * @filname: the filename that's going to be added
2150  * @da: The structure to return dir alloc info
2151  *
2152  * Returns: 0 if ok, -ve on error
2153  */
2154 
2155 int gfs2_diradd_alloc_required(struct inode *inode, const struct qstr *name,
2156                                struct gfs2_diradd *da)
2157 {
2158         struct gfs2_inode *ip = GFS2_I(inode);
2159         struct gfs2_sbd *sdp = GFS2_SB(inode);
2160         const unsigned int extra = sizeof(struct gfs2_dinode) - sizeof(struct gfs2_leaf);
2161         struct gfs2_dirent *dent;
2162         struct buffer_head *bh;
2163 
2164         da->nr_blocks = 0;
2165         da->bh = NULL;
2166         da->dent = NULL;
2167 
2168         dent = gfs2_dirent_search(inode, name, gfs2_dirent_find_space, &bh);
2169         if (!dent) {
2170                 da->nr_blocks = sdp->sd_max_dirres;
2171                 if (!(ip->i_diskflags & GFS2_DIF_EXHASH) &&
2172                     (GFS2_DIRENT_SIZE(name->len) < extra))
2173                         da->nr_blocks = 1;
2174                 return 0;
2175         }
2176         if (IS_ERR(dent))
2177                 return PTR_ERR(dent);
2178 
2179         if (da->save_loc) {
2180                 da->bh = bh;
2181                 da->dent = dent;
2182         } else {
2183                 brelse(bh);
2184         }
2185         return 0;
2186 }
2187 
2188 

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