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[kvmfornfv.git] / kernel / fs / xfs / libxfs / xfs_attr_leaf.c
1 /*
2  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3  * Copyright (c) 2013 Red Hat, Inc.
4  * All Rights Reserved.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License as
8  * published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it would be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write the Free Software Foundation,
17  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
18  */
19 #include "xfs.h"
20 #include "xfs_fs.h"
21 #include "xfs_shared.h"
22 #include "xfs_format.h"
23 #include "xfs_log_format.h"
24 #include "xfs_trans_resv.h"
25 #include "xfs_bit.h"
26 #include "xfs_sb.h"
27 #include "xfs_mount.h"
28 #include "xfs_da_format.h"
29 #include "xfs_da_btree.h"
30 #include "xfs_inode.h"
31 #include "xfs_trans.h"
32 #include "xfs_inode_item.h"
33 #include "xfs_bmap_btree.h"
34 #include "xfs_bmap.h"
35 #include "xfs_attr_sf.h"
36 #include "xfs_attr_remote.h"
37 #include "xfs_attr.h"
38 #include "xfs_attr_leaf.h"
39 #include "xfs_error.h"
40 #include "xfs_trace.h"
41 #include "xfs_buf_item.h"
42 #include "xfs_cksum.h"
43 #include "xfs_dir2.h"
44 #include "xfs_log.h"
45
46
47 /*
48  * xfs_attr_leaf.c
49  *
50  * Routines to implement leaf blocks of attributes as Btrees of hashed names.
51  */
52
53 /*========================================================================
54  * Function prototypes for the kernel.
55  *========================================================================*/
56
57 /*
58  * Routines used for growing the Btree.
59  */
60 STATIC int xfs_attr3_leaf_create(struct xfs_da_args *args,
61                                  xfs_dablk_t which_block, struct xfs_buf **bpp);
62 STATIC int xfs_attr3_leaf_add_work(struct xfs_buf *leaf_buffer,
63                                    struct xfs_attr3_icleaf_hdr *ichdr,
64                                    struct xfs_da_args *args, int freemap_index);
65 STATIC void xfs_attr3_leaf_compact(struct xfs_da_args *args,
66                                    struct xfs_attr3_icleaf_hdr *ichdr,
67                                    struct xfs_buf *leaf_buffer);
68 STATIC void xfs_attr3_leaf_rebalance(xfs_da_state_t *state,
69                                                    xfs_da_state_blk_t *blk1,
70                                                    xfs_da_state_blk_t *blk2);
71 STATIC int xfs_attr3_leaf_figure_balance(xfs_da_state_t *state,
72                         xfs_da_state_blk_t *leaf_blk_1,
73                         struct xfs_attr3_icleaf_hdr *ichdr1,
74                         xfs_da_state_blk_t *leaf_blk_2,
75                         struct xfs_attr3_icleaf_hdr *ichdr2,
76                         int *number_entries_in_blk1,
77                         int *number_usedbytes_in_blk1);
78
79 /*
80  * Utility routines.
81  */
82 STATIC void xfs_attr3_leaf_moveents(struct xfs_da_args *args,
83                         struct xfs_attr_leafblock *src_leaf,
84                         struct xfs_attr3_icleaf_hdr *src_ichdr, int src_start,
85                         struct xfs_attr_leafblock *dst_leaf,
86                         struct xfs_attr3_icleaf_hdr *dst_ichdr, int dst_start,
87                         int move_count);
88 STATIC int xfs_attr_leaf_entsize(xfs_attr_leafblock_t *leaf, int index);
89
90 /*
91  * attr3 block 'firstused' conversion helpers.
92  *
93  * firstused refers to the offset of the first used byte of the nameval region
94  * of an attr leaf block. The region starts at the tail of the block and expands
95  * backwards towards the middle. As such, firstused is initialized to the block
96  * size for an empty leaf block and is reduced from there.
97  *
98  * The attr3 block size is pegged to the fsb size and the maximum fsb is 64k.
99  * The in-core firstused field is 32-bit and thus supports the maximum fsb size.
100  * The on-disk field is only 16-bit, however, and overflows at 64k. Since this
101  * only occurs at exactly 64k, we use zero as a magic on-disk value to represent
102  * the attr block size. The following helpers manage the conversion between the
103  * in-core and on-disk formats.
104  */
105
106 static void
107 xfs_attr3_leaf_firstused_from_disk(
108         struct xfs_da_geometry          *geo,
109         struct xfs_attr3_icleaf_hdr     *to,
110         struct xfs_attr_leafblock       *from)
111 {
112         struct xfs_attr3_leaf_hdr       *hdr3;
113
114         if (from->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) {
115                 hdr3 = (struct xfs_attr3_leaf_hdr *) from;
116                 to->firstused = be16_to_cpu(hdr3->firstused);
117         } else {
118                 to->firstused = be16_to_cpu(from->hdr.firstused);
119         }
120
121         /*
122          * Convert from the magic fsb size value to actual blocksize. This
123          * should only occur for empty blocks when the block size overflows
124          * 16-bits.
125          */
126         if (to->firstused == XFS_ATTR3_LEAF_NULLOFF) {
127                 ASSERT(!to->count && !to->usedbytes);
128                 ASSERT(geo->blksize > USHRT_MAX);
129                 to->firstused = geo->blksize;
130         }
131 }
132
133 static void
134 xfs_attr3_leaf_firstused_to_disk(
135         struct xfs_da_geometry          *geo,
136         struct xfs_attr_leafblock       *to,
137         struct xfs_attr3_icleaf_hdr     *from)
138 {
139         struct xfs_attr3_leaf_hdr       *hdr3;
140         uint32_t                        firstused;
141
142         /* magic value should only be seen on disk */
143         ASSERT(from->firstused != XFS_ATTR3_LEAF_NULLOFF);
144
145         /*
146          * Scale down the 32-bit in-core firstused value to the 16-bit on-disk
147          * value. This only overflows at the max supported value of 64k. Use the
148          * magic on-disk value to represent block size in this case.
149          */
150         firstused = from->firstused;
151         if (firstused > USHRT_MAX) {
152                 ASSERT(from->firstused == geo->blksize);
153                 firstused = XFS_ATTR3_LEAF_NULLOFF;
154         }
155
156         if (from->magic == XFS_ATTR3_LEAF_MAGIC) {
157                 hdr3 = (struct xfs_attr3_leaf_hdr *) to;
158                 hdr3->firstused = cpu_to_be16(firstused);
159         } else {
160                 to->hdr.firstused = cpu_to_be16(firstused);
161         }
162 }
163
164 void
165 xfs_attr3_leaf_hdr_from_disk(
166         struct xfs_da_geometry          *geo,
167         struct xfs_attr3_icleaf_hdr     *to,
168         struct xfs_attr_leafblock       *from)
169 {
170         int     i;
171
172         ASSERT(from->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC) ||
173                from->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC));
174
175         if (from->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) {
176                 struct xfs_attr3_leaf_hdr *hdr3 = (struct xfs_attr3_leaf_hdr *)from;
177
178                 to->forw = be32_to_cpu(hdr3->info.hdr.forw);
179                 to->back = be32_to_cpu(hdr3->info.hdr.back);
180                 to->magic = be16_to_cpu(hdr3->info.hdr.magic);
181                 to->count = be16_to_cpu(hdr3->count);
182                 to->usedbytes = be16_to_cpu(hdr3->usedbytes);
183                 xfs_attr3_leaf_firstused_from_disk(geo, to, from);
184                 to->holes = hdr3->holes;
185
186                 for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
187                         to->freemap[i].base = be16_to_cpu(hdr3->freemap[i].base);
188                         to->freemap[i].size = be16_to_cpu(hdr3->freemap[i].size);
189                 }
190                 return;
191         }
192         to->forw = be32_to_cpu(from->hdr.info.forw);
193         to->back = be32_to_cpu(from->hdr.info.back);
194         to->magic = be16_to_cpu(from->hdr.info.magic);
195         to->count = be16_to_cpu(from->hdr.count);
196         to->usedbytes = be16_to_cpu(from->hdr.usedbytes);
197         xfs_attr3_leaf_firstused_from_disk(geo, to, from);
198         to->holes = from->hdr.holes;
199
200         for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
201                 to->freemap[i].base = be16_to_cpu(from->hdr.freemap[i].base);
202                 to->freemap[i].size = be16_to_cpu(from->hdr.freemap[i].size);
203         }
204 }
205
206 void
207 xfs_attr3_leaf_hdr_to_disk(
208         struct xfs_da_geometry          *geo,
209         struct xfs_attr_leafblock       *to,
210         struct xfs_attr3_icleaf_hdr     *from)
211 {
212         int                             i;
213
214         ASSERT(from->magic == XFS_ATTR_LEAF_MAGIC ||
215                from->magic == XFS_ATTR3_LEAF_MAGIC);
216
217         if (from->magic == XFS_ATTR3_LEAF_MAGIC) {
218                 struct xfs_attr3_leaf_hdr *hdr3 = (struct xfs_attr3_leaf_hdr *)to;
219
220                 hdr3->info.hdr.forw = cpu_to_be32(from->forw);
221                 hdr3->info.hdr.back = cpu_to_be32(from->back);
222                 hdr3->info.hdr.magic = cpu_to_be16(from->magic);
223                 hdr3->count = cpu_to_be16(from->count);
224                 hdr3->usedbytes = cpu_to_be16(from->usedbytes);
225                 xfs_attr3_leaf_firstused_to_disk(geo, to, from);
226                 hdr3->holes = from->holes;
227                 hdr3->pad1 = 0;
228
229                 for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
230                         hdr3->freemap[i].base = cpu_to_be16(from->freemap[i].base);
231                         hdr3->freemap[i].size = cpu_to_be16(from->freemap[i].size);
232                 }
233                 return;
234         }
235         to->hdr.info.forw = cpu_to_be32(from->forw);
236         to->hdr.info.back = cpu_to_be32(from->back);
237         to->hdr.info.magic = cpu_to_be16(from->magic);
238         to->hdr.count = cpu_to_be16(from->count);
239         to->hdr.usedbytes = cpu_to_be16(from->usedbytes);
240         xfs_attr3_leaf_firstused_to_disk(geo, to, from);
241         to->hdr.holes = from->holes;
242         to->hdr.pad1 = 0;
243
244         for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
245                 to->hdr.freemap[i].base = cpu_to_be16(from->freemap[i].base);
246                 to->hdr.freemap[i].size = cpu_to_be16(from->freemap[i].size);
247         }
248 }
249
250 static bool
251 xfs_attr3_leaf_verify(
252         struct xfs_buf          *bp)
253 {
254         struct xfs_mount        *mp = bp->b_target->bt_mount;
255         struct xfs_attr_leafblock *leaf = bp->b_addr;
256         struct xfs_attr3_icleaf_hdr ichdr;
257
258         xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);
259
260         if (xfs_sb_version_hascrc(&mp->m_sb)) {
261                 struct xfs_da3_node_hdr *hdr3 = bp->b_addr;
262
263                 if (ichdr.magic != XFS_ATTR3_LEAF_MAGIC)
264                         return false;
265
266                 if (!uuid_equal(&hdr3->info.uuid, &mp->m_sb.sb_meta_uuid))
267                         return false;
268                 if (be64_to_cpu(hdr3->info.blkno) != bp->b_bn)
269                         return false;
270                 if (!xfs_log_check_lsn(mp, be64_to_cpu(hdr3->info.lsn)))
271                         return false;
272         } else {
273                 if (ichdr.magic != XFS_ATTR_LEAF_MAGIC)
274                         return false;
275         }
276         if (ichdr.count == 0)
277                 return false;
278
279         /* XXX: need to range check rest of attr header values */
280         /* XXX: hash order check? */
281
282         return true;
283 }
284
285 static void
286 xfs_attr3_leaf_write_verify(
287         struct xfs_buf  *bp)
288 {
289         struct xfs_mount        *mp = bp->b_target->bt_mount;
290         struct xfs_buf_log_item *bip = bp->b_fspriv;
291         struct xfs_attr3_leaf_hdr *hdr3 = bp->b_addr;
292
293         if (!xfs_attr3_leaf_verify(bp)) {
294                 xfs_buf_ioerror(bp, -EFSCORRUPTED);
295                 xfs_verifier_error(bp);
296                 return;
297         }
298
299         if (!xfs_sb_version_hascrc(&mp->m_sb))
300                 return;
301
302         if (bip)
303                 hdr3->info.lsn = cpu_to_be64(bip->bli_item.li_lsn);
304
305         xfs_buf_update_cksum(bp, XFS_ATTR3_LEAF_CRC_OFF);
306 }
307
308 /*
309  * leaf/node format detection on trees is sketchy, so a node read can be done on
310  * leaf level blocks when detection identifies the tree as a node format tree
311  * incorrectly. In this case, we need to swap the verifier to match the correct
312  * format of the block being read.
313  */
314 static void
315 xfs_attr3_leaf_read_verify(
316         struct xfs_buf          *bp)
317 {
318         struct xfs_mount        *mp = bp->b_target->bt_mount;
319
320         if (xfs_sb_version_hascrc(&mp->m_sb) &&
321              !xfs_buf_verify_cksum(bp, XFS_ATTR3_LEAF_CRC_OFF))
322                 xfs_buf_ioerror(bp, -EFSBADCRC);
323         else if (!xfs_attr3_leaf_verify(bp))
324                 xfs_buf_ioerror(bp, -EFSCORRUPTED);
325
326         if (bp->b_error)
327                 xfs_verifier_error(bp);
328 }
329
330 const struct xfs_buf_ops xfs_attr3_leaf_buf_ops = {
331         .name = "xfs_attr3_leaf",
332         .verify_read = xfs_attr3_leaf_read_verify,
333         .verify_write = xfs_attr3_leaf_write_verify,
334 };
335
336 int
337 xfs_attr3_leaf_read(
338         struct xfs_trans        *tp,
339         struct xfs_inode        *dp,
340         xfs_dablk_t             bno,
341         xfs_daddr_t             mappedbno,
342         struct xfs_buf          **bpp)
343 {
344         int                     err;
345
346         err = xfs_da_read_buf(tp, dp, bno, mappedbno, bpp,
347                                 XFS_ATTR_FORK, &xfs_attr3_leaf_buf_ops);
348         if (!err && tp)
349                 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_ATTR_LEAF_BUF);
350         return err;
351 }
352
353 /*========================================================================
354  * Namespace helper routines
355  *========================================================================*/
356
357 /*
358  * If namespace bits don't match return 0.
359  * If all match then return 1.
360  */
361 STATIC int
362 xfs_attr_namesp_match(int arg_flags, int ondisk_flags)
363 {
364         return XFS_ATTR_NSP_ONDISK(ondisk_flags) == XFS_ATTR_NSP_ARGS_TO_ONDISK(arg_flags);
365 }
366
367
368 /*========================================================================
369  * External routines when attribute fork size < XFS_LITINO(mp).
370  *========================================================================*/
371
372 /*
373  * Query whether the requested number of additional bytes of extended
374  * attribute space will be able to fit inline.
375  *
376  * Returns zero if not, else the di_forkoff fork offset to be used in the
377  * literal area for attribute data once the new bytes have been added.
378  *
379  * di_forkoff must be 8 byte aligned, hence is stored as a >>3 value;
380  * special case for dev/uuid inodes, they have fixed size data forks.
381  */
382 int
383 xfs_attr_shortform_bytesfit(xfs_inode_t *dp, int bytes)
384 {
385         int offset;
386         int minforkoff; /* lower limit on valid forkoff locations */
387         int maxforkoff; /* upper limit on valid forkoff locations */
388         int dsize;
389         xfs_mount_t *mp = dp->i_mount;
390
391         /* rounded down */
392         offset = (XFS_LITINO(mp, dp->i_d.di_version) - bytes) >> 3;
393
394         switch (dp->i_d.di_format) {
395         case XFS_DINODE_FMT_DEV:
396                 minforkoff = roundup(sizeof(xfs_dev_t), 8) >> 3;
397                 return (offset >= minforkoff) ? minforkoff : 0;
398         case XFS_DINODE_FMT_UUID:
399                 minforkoff = roundup(sizeof(uuid_t), 8) >> 3;
400                 return (offset >= minforkoff) ? minforkoff : 0;
401         }
402
403         /*
404          * If the requested numbers of bytes is smaller or equal to the
405          * current attribute fork size we can always proceed.
406          *
407          * Note that if_bytes in the data fork might actually be larger than
408          * the current data fork size is due to delalloc extents. In that
409          * case either the extent count will go down when they are converted
410          * to real extents, or the delalloc conversion will take care of the
411          * literal area rebalancing.
412          */
413         if (bytes <= XFS_IFORK_ASIZE(dp))
414                 return dp->i_d.di_forkoff;
415
416         /*
417          * For attr2 we can try to move the forkoff if there is space in the
418          * literal area, but for the old format we are done if there is no
419          * space in the fixed attribute fork.
420          */
421         if (!(mp->m_flags & XFS_MOUNT_ATTR2))
422                 return 0;
423
424         dsize = dp->i_df.if_bytes;
425
426         switch (dp->i_d.di_format) {
427         case XFS_DINODE_FMT_EXTENTS:
428                 /*
429                  * If there is no attr fork and the data fork is extents, 
430                  * determine if creating the default attr fork will result
431                  * in the extents form migrating to btree. If so, the
432                  * minimum offset only needs to be the space required for
433                  * the btree root.
434                  */
435                 if (!dp->i_d.di_forkoff && dp->i_df.if_bytes >
436                     xfs_default_attroffset(dp))
437                         dsize = XFS_BMDR_SPACE_CALC(MINDBTPTRS);
438                 break;
439         case XFS_DINODE_FMT_BTREE:
440                 /*
441                  * If we have a data btree then keep forkoff if we have one,
442                  * otherwise we are adding a new attr, so then we set
443                  * minforkoff to where the btree root can finish so we have
444                  * plenty of room for attrs
445                  */
446                 if (dp->i_d.di_forkoff) {
447                         if (offset < dp->i_d.di_forkoff)
448                                 return 0;
449                         return dp->i_d.di_forkoff;
450                 }
451                 dsize = XFS_BMAP_BROOT_SPACE(mp, dp->i_df.if_broot);
452                 break;
453         }
454
455         /*
456          * A data fork btree root must have space for at least
457          * MINDBTPTRS key/ptr pairs if the data fork is small or empty.
458          */
459         minforkoff = MAX(dsize, XFS_BMDR_SPACE_CALC(MINDBTPTRS));
460         minforkoff = roundup(minforkoff, 8) >> 3;
461
462         /* attr fork btree root can have at least this many key/ptr pairs */
463         maxforkoff = XFS_LITINO(mp, dp->i_d.di_version) -
464                         XFS_BMDR_SPACE_CALC(MINABTPTRS);
465         maxforkoff = maxforkoff >> 3;   /* rounded down */
466
467         if (offset >= maxforkoff)
468                 return maxforkoff;
469         if (offset >= minforkoff)
470                 return offset;
471         return 0;
472 }
473
474 /*
475  * Switch on the ATTR2 superblock bit (implies also FEATURES2)
476  */
477 STATIC void
478 xfs_sbversion_add_attr2(xfs_mount_t *mp, xfs_trans_t *tp)
479 {
480         if ((mp->m_flags & XFS_MOUNT_ATTR2) &&
481             !(xfs_sb_version_hasattr2(&mp->m_sb))) {
482                 spin_lock(&mp->m_sb_lock);
483                 if (!xfs_sb_version_hasattr2(&mp->m_sb)) {
484                         xfs_sb_version_addattr2(&mp->m_sb);
485                         spin_unlock(&mp->m_sb_lock);
486                         xfs_log_sb(tp);
487                 } else
488                         spin_unlock(&mp->m_sb_lock);
489         }
490 }
491
492 /*
493  * Create the initial contents of a shortform attribute list.
494  */
495 void
496 xfs_attr_shortform_create(xfs_da_args_t *args)
497 {
498         xfs_attr_sf_hdr_t *hdr;
499         xfs_inode_t *dp;
500         xfs_ifork_t *ifp;
501
502         trace_xfs_attr_sf_create(args);
503
504         dp = args->dp;
505         ASSERT(dp != NULL);
506         ifp = dp->i_afp;
507         ASSERT(ifp != NULL);
508         ASSERT(ifp->if_bytes == 0);
509         if (dp->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS) {
510                 ifp->if_flags &= ~XFS_IFEXTENTS;        /* just in case */
511                 dp->i_d.di_aformat = XFS_DINODE_FMT_LOCAL;
512                 ifp->if_flags |= XFS_IFINLINE;
513         } else {
514                 ASSERT(ifp->if_flags & XFS_IFINLINE);
515         }
516         xfs_idata_realloc(dp, sizeof(*hdr), XFS_ATTR_FORK);
517         hdr = (xfs_attr_sf_hdr_t *)ifp->if_u1.if_data;
518         hdr->count = 0;
519         hdr->totsize = cpu_to_be16(sizeof(*hdr));
520         xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE | XFS_ILOG_ADATA);
521 }
522
523 /*
524  * Add a name/value pair to the shortform attribute list.
525  * Overflow from the inode has already been checked for.
526  */
527 void
528 xfs_attr_shortform_add(xfs_da_args_t *args, int forkoff)
529 {
530         xfs_attr_shortform_t *sf;
531         xfs_attr_sf_entry_t *sfe;
532         int i, offset, size;
533         xfs_mount_t *mp;
534         xfs_inode_t *dp;
535         xfs_ifork_t *ifp;
536
537         trace_xfs_attr_sf_add(args);
538
539         dp = args->dp;
540         mp = dp->i_mount;
541         dp->i_d.di_forkoff = forkoff;
542
543         ifp = dp->i_afp;
544         ASSERT(ifp->if_flags & XFS_IFINLINE);
545         sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
546         sfe = &sf->list[0];
547         for (i = 0; i < sf->hdr.count; sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
548 #ifdef DEBUG
549                 if (sfe->namelen != args->namelen)
550                         continue;
551                 if (memcmp(args->name, sfe->nameval, args->namelen) != 0)
552                         continue;
553                 if (!xfs_attr_namesp_match(args->flags, sfe->flags))
554                         continue;
555                 ASSERT(0);
556 #endif
557         }
558
559         offset = (char *)sfe - (char *)sf;
560         size = XFS_ATTR_SF_ENTSIZE_BYNAME(args->namelen, args->valuelen);
561         xfs_idata_realloc(dp, size, XFS_ATTR_FORK);
562         sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
563         sfe = (xfs_attr_sf_entry_t *)((char *)sf + offset);
564
565         sfe->namelen = args->namelen;
566         sfe->valuelen = args->valuelen;
567         sfe->flags = XFS_ATTR_NSP_ARGS_TO_ONDISK(args->flags);
568         memcpy(sfe->nameval, args->name, args->namelen);
569         memcpy(&sfe->nameval[args->namelen], args->value, args->valuelen);
570         sf->hdr.count++;
571         be16_add_cpu(&sf->hdr.totsize, size);
572         xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE | XFS_ILOG_ADATA);
573
574         xfs_sbversion_add_attr2(mp, args->trans);
575 }
576
577 /*
578  * After the last attribute is removed revert to original inode format,
579  * making all literal area available to the data fork once more.
580  */
581 void
582 xfs_attr_fork_remove(
583         struct xfs_inode        *ip,
584         struct xfs_trans        *tp)
585 {
586         xfs_idestroy_fork(ip, XFS_ATTR_FORK);
587         ip->i_d.di_forkoff = 0;
588         ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
589
590         ASSERT(ip->i_d.di_anextents == 0);
591         ASSERT(ip->i_afp == NULL);
592
593         xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
594 }
595
596 /*
597  * Remove an attribute from the shortform attribute list structure.
598  */
599 int
600 xfs_attr_shortform_remove(xfs_da_args_t *args)
601 {
602         xfs_attr_shortform_t *sf;
603         xfs_attr_sf_entry_t *sfe;
604         int base, size=0, end, totsize, i;
605         xfs_mount_t *mp;
606         xfs_inode_t *dp;
607
608         trace_xfs_attr_sf_remove(args);
609
610         dp = args->dp;
611         mp = dp->i_mount;
612         base = sizeof(xfs_attr_sf_hdr_t);
613         sf = (xfs_attr_shortform_t *)dp->i_afp->if_u1.if_data;
614         sfe = &sf->list[0];
615         end = sf->hdr.count;
616         for (i = 0; i < end; sfe = XFS_ATTR_SF_NEXTENTRY(sfe),
617                                         base += size, i++) {
618                 size = XFS_ATTR_SF_ENTSIZE(sfe);
619                 if (sfe->namelen != args->namelen)
620                         continue;
621                 if (memcmp(sfe->nameval, args->name, args->namelen) != 0)
622                         continue;
623                 if (!xfs_attr_namesp_match(args->flags, sfe->flags))
624                         continue;
625                 break;
626         }
627         if (i == end)
628                 return -ENOATTR;
629
630         /*
631          * Fix up the attribute fork data, covering the hole
632          */
633         end = base + size;
634         totsize = be16_to_cpu(sf->hdr.totsize);
635         if (end != totsize)
636                 memmove(&((char *)sf)[base], &((char *)sf)[end], totsize - end);
637         sf->hdr.count--;
638         be16_add_cpu(&sf->hdr.totsize, -size);
639
640         /*
641          * Fix up the start offset of the attribute fork
642          */
643         totsize -= size;
644         if (totsize == sizeof(xfs_attr_sf_hdr_t) &&
645             (mp->m_flags & XFS_MOUNT_ATTR2) &&
646             (dp->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
647             !(args->op_flags & XFS_DA_OP_ADDNAME)) {
648                 xfs_attr_fork_remove(dp, args->trans);
649         } else {
650                 xfs_idata_realloc(dp, -size, XFS_ATTR_FORK);
651                 dp->i_d.di_forkoff = xfs_attr_shortform_bytesfit(dp, totsize);
652                 ASSERT(dp->i_d.di_forkoff);
653                 ASSERT(totsize > sizeof(xfs_attr_sf_hdr_t) ||
654                                 (args->op_flags & XFS_DA_OP_ADDNAME) ||
655                                 !(mp->m_flags & XFS_MOUNT_ATTR2) ||
656                                 dp->i_d.di_format == XFS_DINODE_FMT_BTREE);
657                 xfs_trans_log_inode(args->trans, dp,
658                                         XFS_ILOG_CORE | XFS_ILOG_ADATA);
659         }
660
661         xfs_sbversion_add_attr2(mp, args->trans);
662
663         return 0;
664 }
665
666 /*
667  * Look up a name in a shortform attribute list structure.
668  */
669 /*ARGSUSED*/
670 int
671 xfs_attr_shortform_lookup(xfs_da_args_t *args)
672 {
673         xfs_attr_shortform_t *sf;
674         xfs_attr_sf_entry_t *sfe;
675         int i;
676         xfs_ifork_t *ifp;
677
678         trace_xfs_attr_sf_lookup(args);
679
680         ifp = args->dp->i_afp;
681         ASSERT(ifp->if_flags & XFS_IFINLINE);
682         sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
683         sfe = &sf->list[0];
684         for (i = 0; i < sf->hdr.count;
685                                 sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
686                 if (sfe->namelen != args->namelen)
687                         continue;
688                 if (memcmp(args->name, sfe->nameval, args->namelen) != 0)
689                         continue;
690                 if (!xfs_attr_namesp_match(args->flags, sfe->flags))
691                         continue;
692                 return -EEXIST;
693         }
694         return -ENOATTR;
695 }
696
697 /*
698  * Look up a name in a shortform attribute list structure.
699  */
700 /*ARGSUSED*/
701 int
702 xfs_attr_shortform_getvalue(xfs_da_args_t *args)
703 {
704         xfs_attr_shortform_t *sf;
705         xfs_attr_sf_entry_t *sfe;
706         int i;
707
708         ASSERT(args->dp->i_afp->if_flags == XFS_IFINLINE);
709         sf = (xfs_attr_shortform_t *)args->dp->i_afp->if_u1.if_data;
710         sfe = &sf->list[0];
711         for (i = 0; i < sf->hdr.count;
712                                 sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
713                 if (sfe->namelen != args->namelen)
714                         continue;
715                 if (memcmp(args->name, sfe->nameval, args->namelen) != 0)
716                         continue;
717                 if (!xfs_attr_namesp_match(args->flags, sfe->flags))
718                         continue;
719                 if (args->flags & ATTR_KERNOVAL) {
720                         args->valuelen = sfe->valuelen;
721                         return -EEXIST;
722                 }
723                 if (args->valuelen < sfe->valuelen) {
724                         args->valuelen = sfe->valuelen;
725                         return -ERANGE;
726                 }
727                 args->valuelen = sfe->valuelen;
728                 memcpy(args->value, &sfe->nameval[args->namelen],
729                                                     args->valuelen);
730                 return -EEXIST;
731         }
732         return -ENOATTR;
733 }
734
735 /*
736  * Convert from using the shortform to the leaf.
737  */
738 int
739 xfs_attr_shortform_to_leaf(xfs_da_args_t *args)
740 {
741         xfs_inode_t *dp;
742         xfs_attr_shortform_t *sf;
743         xfs_attr_sf_entry_t *sfe;
744         xfs_da_args_t nargs;
745         char *tmpbuffer;
746         int error, i, size;
747         xfs_dablk_t blkno;
748         struct xfs_buf *bp;
749         xfs_ifork_t *ifp;
750
751         trace_xfs_attr_sf_to_leaf(args);
752
753         dp = args->dp;
754         ifp = dp->i_afp;
755         sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
756         size = be16_to_cpu(sf->hdr.totsize);
757         tmpbuffer = kmem_alloc(size, KM_SLEEP);
758         ASSERT(tmpbuffer != NULL);
759         memcpy(tmpbuffer, ifp->if_u1.if_data, size);
760         sf = (xfs_attr_shortform_t *)tmpbuffer;
761
762         xfs_idata_realloc(dp, -size, XFS_ATTR_FORK);
763         xfs_bmap_local_to_extents_empty(dp, XFS_ATTR_FORK);
764
765         bp = NULL;
766         error = xfs_da_grow_inode(args, &blkno);
767         if (error) {
768                 /*
769                  * If we hit an IO error middle of the transaction inside
770                  * grow_inode(), we may have inconsistent data. Bail out.
771                  */
772                 if (error == -EIO)
773                         goto out;
774                 xfs_idata_realloc(dp, size, XFS_ATTR_FORK);     /* try to put */
775                 memcpy(ifp->if_u1.if_data, tmpbuffer, size);    /* it back */
776                 goto out;
777         }
778
779         ASSERT(blkno == 0);
780         error = xfs_attr3_leaf_create(args, blkno, &bp);
781         if (error) {
782                 error = xfs_da_shrink_inode(args, 0, bp);
783                 bp = NULL;
784                 if (error)
785                         goto out;
786                 xfs_idata_realloc(dp, size, XFS_ATTR_FORK);     /* try to put */
787                 memcpy(ifp->if_u1.if_data, tmpbuffer, size);    /* it back */
788                 goto out;
789         }
790
791         memset((char *)&nargs, 0, sizeof(nargs));
792         nargs.dp = dp;
793         nargs.geo = args->geo;
794         nargs.firstblock = args->firstblock;
795         nargs.flist = args->flist;
796         nargs.total = args->total;
797         nargs.whichfork = XFS_ATTR_FORK;
798         nargs.trans = args->trans;
799         nargs.op_flags = XFS_DA_OP_OKNOENT;
800
801         sfe = &sf->list[0];
802         for (i = 0; i < sf->hdr.count; i++) {
803                 nargs.name = sfe->nameval;
804                 nargs.namelen = sfe->namelen;
805                 nargs.value = &sfe->nameval[nargs.namelen];
806                 nargs.valuelen = sfe->valuelen;
807                 nargs.hashval = xfs_da_hashname(sfe->nameval,
808                                                 sfe->namelen);
809                 nargs.flags = XFS_ATTR_NSP_ONDISK_TO_ARGS(sfe->flags);
810                 error = xfs_attr3_leaf_lookup_int(bp, &nargs); /* set a->index */
811                 ASSERT(error == -ENOATTR);
812                 error = xfs_attr3_leaf_add(bp, &nargs);
813                 ASSERT(error != -ENOSPC);
814                 if (error)
815                         goto out;
816                 sfe = XFS_ATTR_SF_NEXTENTRY(sfe);
817         }
818         error = 0;
819
820 out:
821         kmem_free(tmpbuffer);
822         return error;
823 }
824
825 /*
826  * Check a leaf attribute block to see if all the entries would fit into
827  * a shortform attribute list.
828  */
829 int
830 xfs_attr_shortform_allfit(
831         struct xfs_buf          *bp,
832         struct xfs_inode        *dp)
833 {
834         struct xfs_attr_leafblock *leaf;
835         struct xfs_attr_leaf_entry *entry;
836         xfs_attr_leaf_name_local_t *name_loc;
837         struct xfs_attr3_icleaf_hdr leafhdr;
838         int                     bytes;
839         int                     i;
840         struct xfs_mount        *mp = bp->b_target->bt_mount;
841
842         leaf = bp->b_addr;
843         xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &leafhdr, leaf);
844         entry = xfs_attr3_leaf_entryp(leaf);
845
846         bytes = sizeof(struct xfs_attr_sf_hdr);
847         for (i = 0; i < leafhdr.count; entry++, i++) {
848                 if (entry->flags & XFS_ATTR_INCOMPLETE)
849                         continue;               /* don't copy partial entries */
850                 if (!(entry->flags & XFS_ATTR_LOCAL))
851                         return 0;
852                 name_loc = xfs_attr3_leaf_name_local(leaf, i);
853                 if (name_loc->namelen >= XFS_ATTR_SF_ENTSIZE_MAX)
854                         return 0;
855                 if (be16_to_cpu(name_loc->valuelen) >= XFS_ATTR_SF_ENTSIZE_MAX)
856                         return 0;
857                 bytes += sizeof(struct xfs_attr_sf_entry) - 1
858                                 + name_loc->namelen
859                                 + be16_to_cpu(name_loc->valuelen);
860         }
861         if ((dp->i_mount->m_flags & XFS_MOUNT_ATTR2) &&
862             (dp->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
863             (bytes == sizeof(struct xfs_attr_sf_hdr)))
864                 return -1;
865         return xfs_attr_shortform_bytesfit(dp, bytes);
866 }
867
868 /*
869  * Convert a leaf attribute list to shortform attribute list
870  */
871 int
872 xfs_attr3_leaf_to_shortform(
873         struct xfs_buf          *bp,
874         struct xfs_da_args      *args,
875         int                     forkoff)
876 {
877         struct xfs_attr_leafblock *leaf;
878         struct xfs_attr3_icleaf_hdr ichdr;
879         struct xfs_attr_leaf_entry *entry;
880         struct xfs_attr_leaf_name_local *name_loc;
881         struct xfs_da_args      nargs;
882         struct xfs_inode        *dp = args->dp;
883         char                    *tmpbuffer;
884         int                     error;
885         int                     i;
886
887         trace_xfs_attr_leaf_to_sf(args);
888
889         tmpbuffer = kmem_alloc(args->geo->blksize, KM_SLEEP);
890         if (!tmpbuffer)
891                 return -ENOMEM;
892
893         memcpy(tmpbuffer, bp->b_addr, args->geo->blksize);
894
895         leaf = (xfs_attr_leafblock_t *)tmpbuffer;
896         xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
897         entry = xfs_attr3_leaf_entryp(leaf);
898
899         /* XXX (dgc): buffer is about to be marked stale - why zero it? */
900         memset(bp->b_addr, 0, args->geo->blksize);
901
902         /*
903          * Clean out the prior contents of the attribute list.
904          */
905         error = xfs_da_shrink_inode(args, 0, bp);
906         if (error)
907                 goto out;
908
909         if (forkoff == -1) {
910                 ASSERT(dp->i_mount->m_flags & XFS_MOUNT_ATTR2);
911                 ASSERT(dp->i_d.di_format != XFS_DINODE_FMT_BTREE);
912                 xfs_attr_fork_remove(dp, args->trans);
913                 goto out;
914         }
915
916         xfs_attr_shortform_create(args);
917
918         /*
919          * Copy the attributes
920          */
921         memset((char *)&nargs, 0, sizeof(nargs));
922         nargs.geo = args->geo;
923         nargs.dp = dp;
924         nargs.firstblock = args->firstblock;
925         nargs.flist = args->flist;
926         nargs.total = args->total;
927         nargs.whichfork = XFS_ATTR_FORK;
928         nargs.trans = args->trans;
929         nargs.op_flags = XFS_DA_OP_OKNOENT;
930
931         for (i = 0; i < ichdr.count; entry++, i++) {
932                 if (entry->flags & XFS_ATTR_INCOMPLETE)
933                         continue;       /* don't copy partial entries */
934                 if (!entry->nameidx)
935                         continue;
936                 ASSERT(entry->flags & XFS_ATTR_LOCAL);
937                 name_loc = xfs_attr3_leaf_name_local(leaf, i);
938                 nargs.name = name_loc->nameval;
939                 nargs.namelen = name_loc->namelen;
940                 nargs.value = &name_loc->nameval[nargs.namelen];
941                 nargs.valuelen = be16_to_cpu(name_loc->valuelen);
942                 nargs.hashval = be32_to_cpu(entry->hashval);
943                 nargs.flags = XFS_ATTR_NSP_ONDISK_TO_ARGS(entry->flags);
944                 xfs_attr_shortform_add(&nargs, forkoff);
945         }
946         error = 0;
947
948 out:
949         kmem_free(tmpbuffer);
950         return error;
951 }
952
953 /*
954  * Convert from using a single leaf to a root node and a leaf.
955  */
956 int
957 xfs_attr3_leaf_to_node(
958         struct xfs_da_args      *args)
959 {
960         struct xfs_attr_leafblock *leaf;
961         struct xfs_attr3_icleaf_hdr icleafhdr;
962         struct xfs_attr_leaf_entry *entries;
963         struct xfs_da_node_entry *btree;
964         struct xfs_da3_icnode_hdr icnodehdr;
965         struct xfs_da_intnode   *node;
966         struct xfs_inode        *dp = args->dp;
967         struct xfs_mount        *mp = dp->i_mount;
968         struct xfs_buf          *bp1 = NULL;
969         struct xfs_buf          *bp2 = NULL;
970         xfs_dablk_t             blkno;
971         int                     error;
972
973         trace_xfs_attr_leaf_to_node(args);
974
975         error = xfs_da_grow_inode(args, &blkno);
976         if (error)
977                 goto out;
978         error = xfs_attr3_leaf_read(args->trans, dp, 0, -1, &bp1);
979         if (error)
980                 goto out;
981
982         error = xfs_da_get_buf(args->trans, dp, blkno, -1, &bp2, XFS_ATTR_FORK);
983         if (error)
984                 goto out;
985
986         /* copy leaf to new buffer, update identifiers */
987         xfs_trans_buf_set_type(args->trans, bp2, XFS_BLFT_ATTR_LEAF_BUF);
988         bp2->b_ops = bp1->b_ops;
989         memcpy(bp2->b_addr, bp1->b_addr, args->geo->blksize);
990         if (xfs_sb_version_hascrc(&mp->m_sb)) {
991                 struct xfs_da3_blkinfo *hdr3 = bp2->b_addr;
992                 hdr3->blkno = cpu_to_be64(bp2->b_bn);
993         }
994         xfs_trans_log_buf(args->trans, bp2, 0, args->geo->blksize - 1);
995
996         /*
997          * Set up the new root node.
998          */
999         error = xfs_da3_node_create(args, 0, 1, &bp1, XFS_ATTR_FORK);
1000         if (error)
1001                 goto out;
1002         node = bp1->b_addr;
1003         dp->d_ops->node_hdr_from_disk(&icnodehdr, node);
1004         btree = dp->d_ops->node_tree_p(node);
1005
1006         leaf = bp2->b_addr;
1007         xfs_attr3_leaf_hdr_from_disk(args->geo, &icleafhdr, leaf);
1008         entries = xfs_attr3_leaf_entryp(leaf);
1009
1010         /* both on-disk, don't endian-flip twice */
1011         btree[0].hashval = entries[icleafhdr.count - 1].hashval;
1012         btree[0].before = cpu_to_be32(blkno);
1013         icnodehdr.count = 1;
1014         dp->d_ops->node_hdr_to_disk(node, &icnodehdr);
1015         xfs_trans_log_buf(args->trans, bp1, 0, args->geo->blksize - 1);
1016         error = 0;
1017 out:
1018         return error;
1019 }
1020
1021 /*========================================================================
1022  * Routines used for growing the Btree.
1023  *========================================================================*/
1024
1025 /*
1026  * Create the initial contents of a leaf attribute list
1027  * or a leaf in a node attribute list.
1028  */
1029 STATIC int
1030 xfs_attr3_leaf_create(
1031         struct xfs_da_args      *args,
1032         xfs_dablk_t             blkno,
1033         struct xfs_buf          **bpp)
1034 {
1035         struct xfs_attr_leafblock *leaf;
1036         struct xfs_attr3_icleaf_hdr ichdr;
1037         struct xfs_inode        *dp = args->dp;
1038         struct xfs_mount        *mp = dp->i_mount;
1039         struct xfs_buf          *bp;
1040         int                     error;
1041
1042         trace_xfs_attr_leaf_create(args);
1043
1044         error = xfs_da_get_buf(args->trans, args->dp, blkno, -1, &bp,
1045                                             XFS_ATTR_FORK);
1046         if (error)
1047                 return error;
1048         bp->b_ops = &xfs_attr3_leaf_buf_ops;
1049         xfs_trans_buf_set_type(args->trans, bp, XFS_BLFT_ATTR_LEAF_BUF);
1050         leaf = bp->b_addr;
1051         memset(leaf, 0, args->geo->blksize);
1052
1053         memset(&ichdr, 0, sizeof(ichdr));
1054         ichdr.firstused = args->geo->blksize;
1055
1056         if (xfs_sb_version_hascrc(&mp->m_sb)) {
1057                 struct xfs_da3_blkinfo *hdr3 = bp->b_addr;
1058
1059                 ichdr.magic = XFS_ATTR3_LEAF_MAGIC;
1060
1061                 hdr3->blkno = cpu_to_be64(bp->b_bn);
1062                 hdr3->owner = cpu_to_be64(dp->i_ino);
1063                 uuid_copy(&hdr3->uuid, &mp->m_sb.sb_meta_uuid);
1064
1065                 ichdr.freemap[0].base = sizeof(struct xfs_attr3_leaf_hdr);
1066         } else {
1067                 ichdr.magic = XFS_ATTR_LEAF_MAGIC;
1068                 ichdr.freemap[0].base = sizeof(struct xfs_attr_leaf_hdr);
1069         }
1070         ichdr.freemap[0].size = ichdr.firstused - ichdr.freemap[0].base;
1071
1072         xfs_attr3_leaf_hdr_to_disk(args->geo, leaf, &ichdr);
1073         xfs_trans_log_buf(args->trans, bp, 0, args->geo->blksize - 1);
1074
1075         *bpp = bp;
1076         return 0;
1077 }
1078
1079 /*
1080  * Split the leaf node, rebalance, then add the new entry.
1081  */
1082 int
1083 xfs_attr3_leaf_split(
1084         struct xfs_da_state     *state,
1085         struct xfs_da_state_blk *oldblk,
1086         struct xfs_da_state_blk *newblk)
1087 {
1088         xfs_dablk_t blkno;
1089         int error;
1090
1091         trace_xfs_attr_leaf_split(state->args);
1092
1093         /*
1094          * Allocate space for a new leaf node.
1095          */
1096         ASSERT(oldblk->magic == XFS_ATTR_LEAF_MAGIC);
1097         error = xfs_da_grow_inode(state->args, &blkno);
1098         if (error)
1099                 return error;
1100         error = xfs_attr3_leaf_create(state->args, blkno, &newblk->bp);
1101         if (error)
1102                 return error;
1103         newblk->blkno = blkno;
1104         newblk->magic = XFS_ATTR_LEAF_MAGIC;
1105
1106         /*
1107          * Rebalance the entries across the two leaves.
1108          * NOTE: rebalance() currently depends on the 2nd block being empty.
1109          */
1110         xfs_attr3_leaf_rebalance(state, oldblk, newblk);
1111         error = xfs_da3_blk_link(state, oldblk, newblk);
1112         if (error)
1113                 return error;
1114
1115         /*
1116          * Save info on "old" attribute for "atomic rename" ops, leaf_add()
1117          * modifies the index/blkno/rmtblk/rmtblkcnt fields to show the
1118          * "new" attrs info.  Will need the "old" info to remove it later.
1119          *
1120          * Insert the "new" entry in the correct block.
1121          */
1122         if (state->inleaf) {
1123                 trace_xfs_attr_leaf_add_old(state->args);
1124                 error = xfs_attr3_leaf_add(oldblk->bp, state->args);
1125         } else {
1126                 trace_xfs_attr_leaf_add_new(state->args);
1127                 error = xfs_attr3_leaf_add(newblk->bp, state->args);
1128         }
1129
1130         /*
1131          * Update last hashval in each block since we added the name.
1132          */
1133         oldblk->hashval = xfs_attr_leaf_lasthash(oldblk->bp, NULL);
1134         newblk->hashval = xfs_attr_leaf_lasthash(newblk->bp, NULL);
1135         return error;
1136 }
1137
1138 /*
1139  * Add a name to the leaf attribute list structure.
1140  */
1141 int
1142 xfs_attr3_leaf_add(
1143         struct xfs_buf          *bp,
1144         struct xfs_da_args      *args)
1145 {
1146         struct xfs_attr_leafblock *leaf;
1147         struct xfs_attr3_icleaf_hdr ichdr;
1148         int                     tablesize;
1149         int                     entsize;
1150         int                     sum;
1151         int                     tmp;
1152         int                     i;
1153
1154         trace_xfs_attr_leaf_add(args);
1155
1156         leaf = bp->b_addr;
1157         xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
1158         ASSERT(args->index >= 0 && args->index <= ichdr.count);
1159         entsize = xfs_attr_leaf_newentsize(args, NULL);
1160
1161         /*
1162          * Search through freemap for first-fit on new name length.
1163          * (may need to figure in size of entry struct too)
1164          */
1165         tablesize = (ichdr.count + 1) * sizeof(xfs_attr_leaf_entry_t)
1166                                         + xfs_attr3_leaf_hdr_size(leaf);
1167         for (sum = 0, i = XFS_ATTR_LEAF_MAPSIZE - 1; i >= 0; i--) {
1168                 if (tablesize > ichdr.firstused) {
1169                         sum += ichdr.freemap[i].size;
1170                         continue;
1171                 }
1172                 if (!ichdr.freemap[i].size)
1173                         continue;       /* no space in this map */
1174                 tmp = entsize;
1175                 if (ichdr.freemap[i].base < ichdr.firstused)
1176                         tmp += sizeof(xfs_attr_leaf_entry_t);
1177                 if (ichdr.freemap[i].size >= tmp) {
1178                         tmp = xfs_attr3_leaf_add_work(bp, &ichdr, args, i);
1179                         goto out_log_hdr;
1180                 }
1181                 sum += ichdr.freemap[i].size;
1182         }
1183
1184         /*
1185          * If there are no holes in the address space of the block,
1186          * and we don't have enough freespace, then compaction will do us
1187          * no good and we should just give up.
1188          */
1189         if (!ichdr.holes && sum < entsize)
1190                 return -ENOSPC;
1191
1192         /*
1193          * Compact the entries to coalesce free space.
1194          * This may change the hdr->count via dropping INCOMPLETE entries.
1195          */
1196         xfs_attr3_leaf_compact(args, &ichdr, bp);
1197
1198         /*
1199          * After compaction, the block is guaranteed to have only one
1200          * free region, in freemap[0].  If it is not big enough, give up.
1201          */
1202         if (ichdr.freemap[0].size < (entsize + sizeof(xfs_attr_leaf_entry_t))) {
1203                 tmp = -ENOSPC;
1204                 goto out_log_hdr;
1205         }
1206
1207         tmp = xfs_attr3_leaf_add_work(bp, &ichdr, args, 0);
1208
1209 out_log_hdr:
1210         xfs_attr3_leaf_hdr_to_disk(args->geo, leaf, &ichdr);
1211         xfs_trans_log_buf(args->trans, bp,
1212                 XFS_DA_LOGRANGE(leaf, &leaf->hdr,
1213                                 xfs_attr3_leaf_hdr_size(leaf)));
1214         return tmp;
1215 }
1216
1217 /*
1218  * Add a name to a leaf attribute list structure.
1219  */
1220 STATIC int
1221 xfs_attr3_leaf_add_work(
1222         struct xfs_buf          *bp,
1223         struct xfs_attr3_icleaf_hdr *ichdr,
1224         struct xfs_da_args      *args,
1225         int                     mapindex)
1226 {
1227         struct xfs_attr_leafblock *leaf;
1228         struct xfs_attr_leaf_entry *entry;
1229         struct xfs_attr_leaf_name_local *name_loc;
1230         struct xfs_attr_leaf_name_remote *name_rmt;
1231         struct xfs_mount        *mp;
1232         int                     tmp;
1233         int                     i;
1234
1235         trace_xfs_attr_leaf_add_work(args);
1236
1237         leaf = bp->b_addr;
1238         ASSERT(mapindex >= 0 && mapindex < XFS_ATTR_LEAF_MAPSIZE);
1239         ASSERT(args->index >= 0 && args->index <= ichdr->count);
1240
1241         /*
1242          * Force open some space in the entry array and fill it in.
1243          */
1244         entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
1245         if (args->index < ichdr->count) {
1246                 tmp  = ichdr->count - args->index;
1247                 tmp *= sizeof(xfs_attr_leaf_entry_t);
1248                 memmove(entry + 1, entry, tmp);
1249                 xfs_trans_log_buf(args->trans, bp,
1250                     XFS_DA_LOGRANGE(leaf, entry, tmp + sizeof(*entry)));
1251         }
1252         ichdr->count++;
1253
1254         /*
1255          * Allocate space for the new string (at the end of the run).
1256          */
1257         mp = args->trans->t_mountp;
1258         ASSERT(ichdr->freemap[mapindex].base < args->geo->blksize);
1259         ASSERT((ichdr->freemap[mapindex].base & 0x3) == 0);
1260         ASSERT(ichdr->freemap[mapindex].size >=
1261                 xfs_attr_leaf_newentsize(args, NULL));
1262         ASSERT(ichdr->freemap[mapindex].size < args->geo->blksize);
1263         ASSERT((ichdr->freemap[mapindex].size & 0x3) == 0);
1264
1265         ichdr->freemap[mapindex].size -= xfs_attr_leaf_newentsize(args, &tmp);
1266
1267         entry->nameidx = cpu_to_be16(ichdr->freemap[mapindex].base +
1268                                      ichdr->freemap[mapindex].size);
1269         entry->hashval = cpu_to_be32(args->hashval);
1270         entry->flags = tmp ? XFS_ATTR_LOCAL : 0;
1271         entry->flags |= XFS_ATTR_NSP_ARGS_TO_ONDISK(args->flags);
1272         if (args->op_flags & XFS_DA_OP_RENAME) {
1273                 entry->flags |= XFS_ATTR_INCOMPLETE;
1274                 if ((args->blkno2 == args->blkno) &&
1275                     (args->index2 <= args->index)) {
1276                         args->index2++;
1277                 }
1278         }
1279         xfs_trans_log_buf(args->trans, bp,
1280                           XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));
1281         ASSERT((args->index == 0) ||
1282                (be32_to_cpu(entry->hashval) >= be32_to_cpu((entry-1)->hashval)));
1283         ASSERT((args->index == ichdr->count - 1) ||
1284                (be32_to_cpu(entry->hashval) <= be32_to_cpu((entry+1)->hashval)));
1285
1286         /*
1287          * For "remote" attribute values, simply note that we need to
1288          * allocate space for the "remote" value.  We can't actually
1289          * allocate the extents in this transaction, and we can't decide
1290          * which blocks they should be as we might allocate more blocks
1291          * as part of this transaction (a split operation for example).
1292          */
1293         if (entry->flags & XFS_ATTR_LOCAL) {
1294                 name_loc = xfs_attr3_leaf_name_local(leaf, args->index);
1295                 name_loc->namelen = args->namelen;
1296                 name_loc->valuelen = cpu_to_be16(args->valuelen);
1297                 memcpy((char *)name_loc->nameval, args->name, args->namelen);
1298                 memcpy((char *)&name_loc->nameval[args->namelen], args->value,
1299                                    be16_to_cpu(name_loc->valuelen));
1300         } else {
1301                 name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
1302                 name_rmt->namelen = args->namelen;
1303                 memcpy((char *)name_rmt->name, args->name, args->namelen);
1304                 entry->flags |= XFS_ATTR_INCOMPLETE;
1305                 /* just in case */
1306                 name_rmt->valuelen = 0;
1307                 name_rmt->valueblk = 0;
1308                 args->rmtblkno = 1;
1309                 args->rmtblkcnt = xfs_attr3_rmt_blocks(mp, args->valuelen);
1310                 args->rmtvaluelen = args->valuelen;
1311         }
1312         xfs_trans_log_buf(args->trans, bp,
1313              XFS_DA_LOGRANGE(leaf, xfs_attr3_leaf_name(leaf, args->index),
1314                                    xfs_attr_leaf_entsize(leaf, args->index)));
1315
1316         /*
1317          * Update the control info for this leaf node
1318          */
1319         if (be16_to_cpu(entry->nameidx) < ichdr->firstused)
1320                 ichdr->firstused = be16_to_cpu(entry->nameidx);
1321
1322         ASSERT(ichdr->firstused >= ichdr->count * sizeof(xfs_attr_leaf_entry_t)
1323                                         + xfs_attr3_leaf_hdr_size(leaf));
1324         tmp = (ichdr->count - 1) * sizeof(xfs_attr_leaf_entry_t)
1325                                         + xfs_attr3_leaf_hdr_size(leaf);
1326
1327         for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
1328                 if (ichdr->freemap[i].base == tmp) {
1329                         ichdr->freemap[i].base += sizeof(xfs_attr_leaf_entry_t);
1330                         ichdr->freemap[i].size -= sizeof(xfs_attr_leaf_entry_t);
1331                 }
1332         }
1333         ichdr->usedbytes += xfs_attr_leaf_entsize(leaf, args->index);
1334         return 0;
1335 }
1336
1337 /*
1338  * Garbage collect a leaf attribute list block by copying it to a new buffer.
1339  */
1340 STATIC void
1341 xfs_attr3_leaf_compact(
1342         struct xfs_da_args      *args,
1343         struct xfs_attr3_icleaf_hdr *ichdr_dst,
1344         struct xfs_buf          *bp)
1345 {
1346         struct xfs_attr_leafblock *leaf_src;
1347         struct xfs_attr_leafblock *leaf_dst;
1348         struct xfs_attr3_icleaf_hdr ichdr_src;
1349         struct xfs_trans        *trans = args->trans;
1350         char                    *tmpbuffer;
1351
1352         trace_xfs_attr_leaf_compact(args);
1353
1354         tmpbuffer = kmem_alloc(args->geo->blksize, KM_SLEEP);
1355         memcpy(tmpbuffer, bp->b_addr, args->geo->blksize);
1356         memset(bp->b_addr, 0, args->geo->blksize);
1357         leaf_src = (xfs_attr_leafblock_t *)tmpbuffer;
1358         leaf_dst = bp->b_addr;
1359
1360         /*
1361          * Copy the on-disk header back into the destination buffer to ensure
1362          * all the information in the header that is not part of the incore
1363          * header structure is preserved.
1364          */
1365         memcpy(bp->b_addr, tmpbuffer, xfs_attr3_leaf_hdr_size(leaf_src));
1366
1367         /* Initialise the incore headers */
1368         ichdr_src = *ichdr_dst; /* struct copy */
1369         ichdr_dst->firstused = args->geo->blksize;
1370         ichdr_dst->usedbytes = 0;
1371         ichdr_dst->count = 0;
1372         ichdr_dst->holes = 0;
1373         ichdr_dst->freemap[0].base = xfs_attr3_leaf_hdr_size(leaf_src);
1374         ichdr_dst->freemap[0].size = ichdr_dst->firstused -
1375                                                 ichdr_dst->freemap[0].base;
1376
1377         /* write the header back to initialise the underlying buffer */
1378         xfs_attr3_leaf_hdr_to_disk(args->geo, leaf_dst, ichdr_dst);
1379
1380         /*
1381          * Copy all entry's in the same (sorted) order,
1382          * but allocate name/value pairs packed and in sequence.
1383          */
1384         xfs_attr3_leaf_moveents(args, leaf_src, &ichdr_src, 0,
1385                                 leaf_dst, ichdr_dst, 0, ichdr_src.count);
1386         /*
1387          * this logs the entire buffer, but the caller must write the header
1388          * back to the buffer when it is finished modifying it.
1389          */
1390         xfs_trans_log_buf(trans, bp, 0, args->geo->blksize - 1);
1391
1392         kmem_free(tmpbuffer);
1393 }
1394
1395 /*
1396  * Compare two leaf blocks "order".
1397  * Return 0 unless leaf2 should go before leaf1.
1398  */
1399 static int
1400 xfs_attr3_leaf_order(
1401         struct xfs_buf  *leaf1_bp,
1402         struct xfs_attr3_icleaf_hdr *leaf1hdr,
1403         struct xfs_buf  *leaf2_bp,
1404         struct xfs_attr3_icleaf_hdr *leaf2hdr)
1405 {
1406         struct xfs_attr_leaf_entry *entries1;
1407         struct xfs_attr_leaf_entry *entries2;
1408
1409         entries1 = xfs_attr3_leaf_entryp(leaf1_bp->b_addr);
1410         entries2 = xfs_attr3_leaf_entryp(leaf2_bp->b_addr);
1411         if (leaf1hdr->count > 0 && leaf2hdr->count > 0 &&
1412             ((be32_to_cpu(entries2[0].hashval) <
1413               be32_to_cpu(entries1[0].hashval)) ||
1414              (be32_to_cpu(entries2[leaf2hdr->count - 1].hashval) <
1415               be32_to_cpu(entries1[leaf1hdr->count - 1].hashval)))) {
1416                 return 1;
1417         }
1418         return 0;
1419 }
1420
1421 int
1422 xfs_attr_leaf_order(
1423         struct xfs_buf  *leaf1_bp,
1424         struct xfs_buf  *leaf2_bp)
1425 {
1426         struct xfs_attr3_icleaf_hdr ichdr1;
1427         struct xfs_attr3_icleaf_hdr ichdr2;
1428         struct xfs_mount *mp = leaf1_bp->b_target->bt_mount;
1429
1430         xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr1, leaf1_bp->b_addr);
1431         xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr2, leaf2_bp->b_addr);
1432         return xfs_attr3_leaf_order(leaf1_bp, &ichdr1, leaf2_bp, &ichdr2);
1433 }
1434
1435 /*
1436  * Redistribute the attribute list entries between two leaf nodes,
1437  * taking into account the size of the new entry.
1438  *
1439  * NOTE: if new block is empty, then it will get the upper half of the
1440  * old block.  At present, all (one) callers pass in an empty second block.
1441  *
1442  * This code adjusts the args->index/blkno and args->index2/blkno2 fields
1443  * to match what it is doing in splitting the attribute leaf block.  Those
1444  * values are used in "atomic rename" operations on attributes.  Note that
1445  * the "new" and "old" values can end up in different blocks.
1446  */
1447 STATIC void
1448 xfs_attr3_leaf_rebalance(
1449         struct xfs_da_state     *state,
1450         struct xfs_da_state_blk *blk1,
1451         struct xfs_da_state_blk *blk2)
1452 {
1453         struct xfs_da_args      *args;
1454         struct xfs_attr_leafblock *leaf1;
1455         struct xfs_attr_leafblock *leaf2;
1456         struct xfs_attr3_icleaf_hdr ichdr1;
1457         struct xfs_attr3_icleaf_hdr ichdr2;
1458         struct xfs_attr_leaf_entry *entries1;
1459         struct xfs_attr_leaf_entry *entries2;
1460         int                     count;
1461         int                     totallen;
1462         int                     max;
1463         int                     space;
1464         int                     swap;
1465
1466         /*
1467          * Set up environment.
1468          */
1469         ASSERT(blk1->magic == XFS_ATTR_LEAF_MAGIC);
1470         ASSERT(blk2->magic == XFS_ATTR_LEAF_MAGIC);
1471         leaf1 = blk1->bp->b_addr;
1472         leaf2 = blk2->bp->b_addr;
1473         xfs_attr3_leaf_hdr_from_disk(state->args->geo, &ichdr1, leaf1);
1474         xfs_attr3_leaf_hdr_from_disk(state->args->geo, &ichdr2, leaf2);
1475         ASSERT(ichdr2.count == 0);
1476         args = state->args;
1477
1478         trace_xfs_attr_leaf_rebalance(args);
1479
1480         /*
1481          * Check ordering of blocks, reverse if it makes things simpler.
1482          *
1483          * NOTE: Given that all (current) callers pass in an empty
1484          * second block, this code should never set "swap".
1485          */
1486         swap = 0;
1487         if (xfs_attr3_leaf_order(blk1->bp, &ichdr1, blk2->bp, &ichdr2)) {
1488                 struct xfs_da_state_blk *tmp_blk;
1489                 struct xfs_attr3_icleaf_hdr tmp_ichdr;
1490
1491                 tmp_blk = blk1;
1492                 blk1 = blk2;
1493                 blk2 = tmp_blk;
1494
1495                 /* struct copies to swap them rather than reconverting */
1496                 tmp_ichdr = ichdr1;
1497                 ichdr1 = ichdr2;
1498                 ichdr2 = tmp_ichdr;
1499
1500                 leaf1 = blk1->bp->b_addr;
1501                 leaf2 = blk2->bp->b_addr;
1502                 swap = 1;
1503         }
1504
1505         /*
1506          * Examine entries until we reduce the absolute difference in
1507          * byte usage between the two blocks to a minimum.  Then get
1508          * the direction to copy and the number of elements to move.
1509          *
1510          * "inleaf" is true if the new entry should be inserted into blk1.
1511          * If "swap" is also true, then reverse the sense of "inleaf".
1512          */
1513         state->inleaf = xfs_attr3_leaf_figure_balance(state, blk1, &ichdr1,
1514                                                       blk2, &ichdr2,
1515                                                       &count, &totallen);
1516         if (swap)
1517                 state->inleaf = !state->inleaf;
1518
1519         /*
1520          * Move any entries required from leaf to leaf:
1521          */
1522         if (count < ichdr1.count) {
1523                 /*
1524                  * Figure the total bytes to be added to the destination leaf.
1525                  */
1526                 /* number entries being moved */
1527                 count = ichdr1.count - count;
1528                 space  = ichdr1.usedbytes - totallen;
1529                 space += count * sizeof(xfs_attr_leaf_entry_t);
1530
1531                 /*
1532                  * leaf2 is the destination, compact it if it looks tight.
1533                  */
1534                 max  = ichdr2.firstused - xfs_attr3_leaf_hdr_size(leaf1);
1535                 max -= ichdr2.count * sizeof(xfs_attr_leaf_entry_t);
1536                 if (space > max)
1537                         xfs_attr3_leaf_compact(args, &ichdr2, blk2->bp);
1538
1539                 /*
1540                  * Move high entries from leaf1 to low end of leaf2.
1541                  */
1542                 xfs_attr3_leaf_moveents(args, leaf1, &ichdr1,
1543                                 ichdr1.count - count, leaf2, &ichdr2, 0, count);
1544
1545         } else if (count > ichdr1.count) {
1546                 /*
1547                  * I assert that since all callers pass in an empty
1548                  * second buffer, this code should never execute.
1549                  */
1550                 ASSERT(0);
1551
1552                 /*
1553                  * Figure the total bytes to be added to the destination leaf.
1554                  */
1555                 /* number entries being moved */
1556                 count -= ichdr1.count;
1557                 space  = totallen - ichdr1.usedbytes;
1558                 space += count * sizeof(xfs_attr_leaf_entry_t);
1559
1560                 /*
1561                  * leaf1 is the destination, compact it if it looks tight.
1562                  */
1563                 max  = ichdr1.firstused - xfs_attr3_leaf_hdr_size(leaf1);
1564                 max -= ichdr1.count * sizeof(xfs_attr_leaf_entry_t);
1565                 if (space > max)
1566                         xfs_attr3_leaf_compact(args, &ichdr1, blk1->bp);
1567
1568                 /*
1569                  * Move low entries from leaf2 to high end of leaf1.
1570                  */
1571                 xfs_attr3_leaf_moveents(args, leaf2, &ichdr2, 0, leaf1, &ichdr1,
1572                                         ichdr1.count, count);
1573         }
1574
1575         xfs_attr3_leaf_hdr_to_disk(state->args->geo, leaf1, &ichdr1);
1576         xfs_attr3_leaf_hdr_to_disk(state->args->geo, leaf2, &ichdr2);
1577         xfs_trans_log_buf(args->trans, blk1->bp, 0, args->geo->blksize - 1);
1578         xfs_trans_log_buf(args->trans, blk2->bp, 0, args->geo->blksize - 1);
1579
1580         /*
1581          * Copy out last hashval in each block for B-tree code.
1582          */
1583         entries1 = xfs_attr3_leaf_entryp(leaf1);
1584         entries2 = xfs_attr3_leaf_entryp(leaf2);
1585         blk1->hashval = be32_to_cpu(entries1[ichdr1.count - 1].hashval);
1586         blk2->hashval = be32_to_cpu(entries2[ichdr2.count - 1].hashval);
1587
1588         /*
1589          * Adjust the expected index for insertion.
1590          * NOTE: this code depends on the (current) situation that the
1591          * second block was originally empty.
1592          *
1593          * If the insertion point moved to the 2nd block, we must adjust
1594          * the index.  We must also track the entry just following the
1595          * new entry for use in an "atomic rename" operation, that entry
1596          * is always the "old" entry and the "new" entry is what we are
1597          * inserting.  The index/blkno fields refer to the "old" entry,
1598          * while the index2/blkno2 fields refer to the "new" entry.
1599          */
1600         if (blk1->index > ichdr1.count) {
1601                 ASSERT(state->inleaf == 0);
1602                 blk2->index = blk1->index - ichdr1.count;
1603                 args->index = args->index2 = blk2->index;
1604                 args->blkno = args->blkno2 = blk2->blkno;
1605         } else if (blk1->index == ichdr1.count) {
1606                 if (state->inleaf) {
1607                         args->index = blk1->index;
1608                         args->blkno = blk1->blkno;
1609                         args->index2 = 0;
1610                         args->blkno2 = blk2->blkno;
1611                 } else {
1612                         /*
1613                          * On a double leaf split, the original attr location
1614                          * is already stored in blkno2/index2, so don't
1615                          * overwrite it overwise we corrupt the tree.
1616                          */
1617                         blk2->index = blk1->index - ichdr1.count;
1618                         args->index = blk2->index;
1619                         args->blkno = blk2->blkno;
1620                         if (!state->extravalid) {
1621                                 /*
1622                                  * set the new attr location to match the old
1623                                  * one and let the higher level split code
1624                                  * decide where in the leaf to place it.
1625                                  */
1626                                 args->index2 = blk2->index;
1627                                 args->blkno2 = blk2->blkno;
1628                         }
1629                 }
1630         } else {
1631                 ASSERT(state->inleaf == 1);
1632                 args->index = args->index2 = blk1->index;
1633                 args->blkno = args->blkno2 = blk1->blkno;
1634         }
1635 }
1636
1637 /*
1638  * Examine entries until we reduce the absolute difference in
1639  * byte usage between the two blocks to a minimum.
1640  * GROT: Is this really necessary?  With other than a 512 byte blocksize,
1641  * GROT: there will always be enough room in either block for a new entry.
1642  * GROT: Do a double-split for this case?
1643  */
1644 STATIC int
1645 xfs_attr3_leaf_figure_balance(
1646         struct xfs_da_state             *state,
1647         struct xfs_da_state_blk         *blk1,
1648         struct xfs_attr3_icleaf_hdr     *ichdr1,
1649         struct xfs_da_state_blk         *blk2,
1650         struct xfs_attr3_icleaf_hdr     *ichdr2,
1651         int                             *countarg,
1652         int                             *usedbytesarg)
1653 {
1654         struct xfs_attr_leafblock       *leaf1 = blk1->bp->b_addr;
1655         struct xfs_attr_leafblock       *leaf2 = blk2->bp->b_addr;
1656         struct xfs_attr_leaf_entry      *entry;
1657         int                             count;
1658         int                             max;
1659         int                             index;
1660         int                             totallen = 0;
1661         int                             half;
1662         int                             lastdelta;
1663         int                             foundit = 0;
1664         int                             tmp;
1665
1666         /*
1667          * Examine entries until we reduce the absolute difference in
1668          * byte usage between the two blocks to a minimum.
1669          */
1670         max = ichdr1->count + ichdr2->count;
1671         half = (max + 1) * sizeof(*entry);
1672         half += ichdr1->usedbytes + ichdr2->usedbytes +
1673                         xfs_attr_leaf_newentsize(state->args, NULL);
1674         half /= 2;
1675         lastdelta = state->args->geo->blksize;
1676         entry = xfs_attr3_leaf_entryp(leaf1);
1677         for (count = index = 0; count < max; entry++, index++, count++) {
1678
1679 #define XFS_ATTR_ABS(A) (((A) < 0) ? -(A) : (A))
1680                 /*
1681                  * The new entry is in the first block, account for it.
1682                  */
1683                 if (count == blk1->index) {
1684                         tmp = totallen + sizeof(*entry) +
1685                                 xfs_attr_leaf_newentsize(state->args, NULL);
1686                         if (XFS_ATTR_ABS(half - tmp) > lastdelta)
1687                                 break;
1688                         lastdelta = XFS_ATTR_ABS(half - tmp);
1689                         totallen = tmp;
1690                         foundit = 1;
1691                 }
1692
1693                 /*
1694                  * Wrap around into the second block if necessary.
1695                  */
1696                 if (count == ichdr1->count) {
1697                         leaf1 = leaf2;
1698                         entry = xfs_attr3_leaf_entryp(leaf1);
1699                         index = 0;
1700                 }
1701
1702                 /*
1703                  * Figure out if next leaf entry would be too much.
1704                  */
1705                 tmp = totallen + sizeof(*entry) + xfs_attr_leaf_entsize(leaf1,
1706                                                                         index);
1707                 if (XFS_ATTR_ABS(half - tmp) > lastdelta)
1708                         break;
1709                 lastdelta = XFS_ATTR_ABS(half - tmp);
1710                 totallen = tmp;
1711 #undef XFS_ATTR_ABS
1712         }
1713
1714         /*
1715          * Calculate the number of usedbytes that will end up in lower block.
1716          * If new entry not in lower block, fix up the count.
1717          */
1718         totallen -= count * sizeof(*entry);
1719         if (foundit) {
1720                 totallen -= sizeof(*entry) +
1721                                 xfs_attr_leaf_newentsize(state->args, NULL);
1722         }
1723
1724         *countarg = count;
1725         *usedbytesarg = totallen;
1726         return foundit;
1727 }
1728
1729 /*========================================================================
1730  * Routines used for shrinking the Btree.
1731  *========================================================================*/
1732
1733 /*
1734  * Check a leaf block and its neighbors to see if the block should be
1735  * collapsed into one or the other neighbor.  Always keep the block
1736  * with the smaller block number.
1737  * If the current block is over 50% full, don't try to join it, return 0.
1738  * If the block is empty, fill in the state structure and return 2.
1739  * If it can be collapsed, fill in the state structure and return 1.
1740  * If nothing can be done, return 0.
1741  *
1742  * GROT: allow for INCOMPLETE entries in calculation.
1743  */
1744 int
1745 xfs_attr3_leaf_toosmall(
1746         struct xfs_da_state     *state,
1747         int                     *action)
1748 {
1749         struct xfs_attr_leafblock *leaf;
1750         struct xfs_da_state_blk *blk;
1751         struct xfs_attr3_icleaf_hdr ichdr;
1752         struct xfs_buf          *bp;
1753         xfs_dablk_t             blkno;
1754         int                     bytes;
1755         int                     forward;
1756         int                     error;
1757         int                     retval;
1758         int                     i;
1759
1760         trace_xfs_attr_leaf_toosmall(state->args);
1761
1762         /*
1763          * Check for the degenerate case of the block being over 50% full.
1764          * If so, it's not worth even looking to see if we might be able
1765          * to coalesce with a sibling.
1766          */
1767         blk = &state->path.blk[ state->path.active-1 ];
1768         leaf = blk->bp->b_addr;
1769         xfs_attr3_leaf_hdr_from_disk(state->args->geo, &ichdr, leaf);
1770         bytes = xfs_attr3_leaf_hdr_size(leaf) +
1771                 ichdr.count * sizeof(xfs_attr_leaf_entry_t) +
1772                 ichdr.usedbytes;
1773         if (bytes > (state->args->geo->blksize >> 1)) {
1774                 *action = 0;    /* blk over 50%, don't try to join */
1775                 return 0;
1776         }
1777
1778         /*
1779          * Check for the degenerate case of the block being empty.
1780          * If the block is empty, we'll simply delete it, no need to
1781          * coalesce it with a sibling block.  We choose (arbitrarily)
1782          * to merge with the forward block unless it is NULL.
1783          */
1784         if (ichdr.count == 0) {
1785                 /*
1786                  * Make altpath point to the block we want to keep and
1787                  * path point to the block we want to drop (this one).
1788                  */
1789                 forward = (ichdr.forw != 0);
1790                 memcpy(&state->altpath, &state->path, sizeof(state->path));
1791                 error = xfs_da3_path_shift(state, &state->altpath, forward,
1792                                                  0, &retval);
1793                 if (error)
1794                         return error;
1795                 if (retval) {
1796                         *action = 0;
1797                 } else {
1798                         *action = 2;
1799                 }
1800                 return 0;
1801         }
1802
1803         /*
1804          * Examine each sibling block to see if we can coalesce with
1805          * at least 25% free space to spare.  We need to figure out
1806          * whether to merge with the forward or the backward block.
1807          * We prefer coalescing with the lower numbered sibling so as
1808          * to shrink an attribute list over time.
1809          */
1810         /* start with smaller blk num */
1811         forward = ichdr.forw < ichdr.back;
1812         for (i = 0; i < 2; forward = !forward, i++) {
1813                 struct xfs_attr3_icleaf_hdr ichdr2;
1814                 if (forward)
1815                         blkno = ichdr.forw;
1816                 else
1817                         blkno = ichdr.back;
1818                 if (blkno == 0)
1819                         continue;
1820                 error = xfs_attr3_leaf_read(state->args->trans, state->args->dp,
1821                                         blkno, -1, &bp);
1822                 if (error)
1823                         return error;
1824
1825                 xfs_attr3_leaf_hdr_from_disk(state->args->geo, &ichdr2, bp->b_addr);
1826
1827                 bytes = state->args->geo->blksize -
1828                         (state->args->geo->blksize >> 2) -
1829                         ichdr.usedbytes - ichdr2.usedbytes -
1830                         ((ichdr.count + ichdr2.count) *
1831                                         sizeof(xfs_attr_leaf_entry_t)) -
1832                         xfs_attr3_leaf_hdr_size(leaf);
1833
1834                 xfs_trans_brelse(state->args->trans, bp);
1835                 if (bytes >= 0)
1836                         break;  /* fits with at least 25% to spare */
1837         }
1838         if (i >= 2) {
1839                 *action = 0;
1840                 return 0;
1841         }
1842
1843         /*
1844          * Make altpath point to the block we want to keep (the lower
1845          * numbered block) and path point to the block we want to drop.
1846          */
1847         memcpy(&state->altpath, &state->path, sizeof(state->path));
1848         if (blkno < blk->blkno) {
1849                 error = xfs_da3_path_shift(state, &state->altpath, forward,
1850                                                  0, &retval);
1851         } else {
1852                 error = xfs_da3_path_shift(state, &state->path, forward,
1853                                                  0, &retval);
1854         }
1855         if (error)
1856                 return error;
1857         if (retval) {
1858                 *action = 0;
1859         } else {
1860                 *action = 1;
1861         }
1862         return 0;
1863 }
1864
1865 /*
1866  * Remove a name from the leaf attribute list structure.
1867  *
1868  * Return 1 if leaf is less than 37% full, 0 if >= 37% full.
1869  * If two leaves are 37% full, when combined they will leave 25% free.
1870  */
1871 int
1872 xfs_attr3_leaf_remove(
1873         struct xfs_buf          *bp,
1874         struct xfs_da_args      *args)
1875 {
1876         struct xfs_attr_leafblock *leaf;
1877         struct xfs_attr3_icleaf_hdr ichdr;
1878         struct xfs_attr_leaf_entry *entry;
1879         int                     before;
1880         int                     after;
1881         int                     smallest;
1882         int                     entsize;
1883         int                     tablesize;
1884         int                     tmp;
1885         int                     i;
1886
1887         trace_xfs_attr_leaf_remove(args);
1888
1889         leaf = bp->b_addr;
1890         xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
1891
1892         ASSERT(ichdr.count > 0 && ichdr.count < args->geo->blksize / 8);
1893         ASSERT(args->index >= 0 && args->index < ichdr.count);
1894         ASSERT(ichdr.firstused >= ichdr.count * sizeof(*entry) +
1895                                         xfs_attr3_leaf_hdr_size(leaf));
1896
1897         entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
1898
1899         ASSERT(be16_to_cpu(entry->nameidx) >= ichdr.firstused);
1900         ASSERT(be16_to_cpu(entry->nameidx) < args->geo->blksize);
1901
1902         /*
1903          * Scan through free region table:
1904          *    check for adjacency of free'd entry with an existing one,
1905          *    find smallest free region in case we need to replace it,
1906          *    adjust any map that borders the entry table,
1907          */
1908         tablesize = ichdr.count * sizeof(xfs_attr_leaf_entry_t)
1909                                         + xfs_attr3_leaf_hdr_size(leaf);
1910         tmp = ichdr.freemap[0].size;
1911         before = after = -1;
1912         smallest = XFS_ATTR_LEAF_MAPSIZE - 1;
1913         entsize = xfs_attr_leaf_entsize(leaf, args->index);
1914         for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
1915                 ASSERT(ichdr.freemap[i].base < args->geo->blksize);
1916                 ASSERT(ichdr.freemap[i].size < args->geo->blksize);
1917                 if (ichdr.freemap[i].base == tablesize) {
1918                         ichdr.freemap[i].base -= sizeof(xfs_attr_leaf_entry_t);
1919                         ichdr.freemap[i].size += sizeof(xfs_attr_leaf_entry_t);
1920                 }
1921
1922                 if (ichdr.freemap[i].base + ichdr.freemap[i].size ==
1923                                 be16_to_cpu(entry->nameidx)) {
1924                         before = i;
1925                 } else if (ichdr.freemap[i].base ==
1926                                 (be16_to_cpu(entry->nameidx) + entsize)) {
1927                         after = i;
1928                 } else if (ichdr.freemap[i].size < tmp) {
1929                         tmp = ichdr.freemap[i].size;
1930                         smallest = i;
1931                 }
1932         }
1933
1934         /*
1935          * Coalesce adjacent freemap regions,
1936          * or replace the smallest region.
1937          */
1938         if ((before >= 0) || (after >= 0)) {
1939                 if ((before >= 0) && (after >= 0)) {
1940                         ichdr.freemap[before].size += entsize;
1941                         ichdr.freemap[before].size += ichdr.freemap[after].size;
1942                         ichdr.freemap[after].base = 0;
1943                         ichdr.freemap[after].size = 0;
1944                 } else if (before >= 0) {
1945                         ichdr.freemap[before].size += entsize;
1946                 } else {
1947                         ichdr.freemap[after].base = be16_to_cpu(entry->nameidx);
1948                         ichdr.freemap[after].size += entsize;
1949                 }
1950         } else {
1951                 /*
1952                  * Replace smallest region (if it is smaller than free'd entry)
1953                  */
1954                 if (ichdr.freemap[smallest].size < entsize) {
1955                         ichdr.freemap[smallest].base = be16_to_cpu(entry->nameidx);
1956                         ichdr.freemap[smallest].size = entsize;
1957                 }
1958         }
1959
1960         /*
1961          * Did we remove the first entry?
1962          */
1963         if (be16_to_cpu(entry->nameidx) == ichdr.firstused)
1964                 smallest = 1;
1965         else
1966                 smallest = 0;
1967
1968         /*
1969          * Compress the remaining entries and zero out the removed stuff.
1970          */
1971         memset(xfs_attr3_leaf_name(leaf, args->index), 0, entsize);
1972         ichdr.usedbytes -= entsize;
1973         xfs_trans_log_buf(args->trans, bp,
1974              XFS_DA_LOGRANGE(leaf, xfs_attr3_leaf_name(leaf, args->index),
1975                                    entsize));
1976
1977         tmp = (ichdr.count - args->index) * sizeof(xfs_attr_leaf_entry_t);
1978         memmove(entry, entry + 1, tmp);
1979         ichdr.count--;
1980         xfs_trans_log_buf(args->trans, bp,
1981             XFS_DA_LOGRANGE(leaf, entry, tmp + sizeof(xfs_attr_leaf_entry_t)));
1982
1983         entry = &xfs_attr3_leaf_entryp(leaf)[ichdr.count];
1984         memset(entry, 0, sizeof(xfs_attr_leaf_entry_t));
1985
1986         /*
1987          * If we removed the first entry, re-find the first used byte
1988          * in the name area.  Note that if the entry was the "firstused",
1989          * then we don't have a "hole" in our block resulting from
1990          * removing the name.
1991          */
1992         if (smallest) {
1993                 tmp = args->geo->blksize;
1994                 entry = xfs_attr3_leaf_entryp(leaf);
1995                 for (i = ichdr.count - 1; i >= 0; entry++, i--) {
1996                         ASSERT(be16_to_cpu(entry->nameidx) >= ichdr.firstused);
1997                         ASSERT(be16_to_cpu(entry->nameidx) < args->geo->blksize);
1998
1999                         if (be16_to_cpu(entry->nameidx) < tmp)
2000                                 tmp = be16_to_cpu(entry->nameidx);
2001                 }
2002                 ichdr.firstused = tmp;
2003                 ASSERT(ichdr.firstused != 0);
2004         } else {
2005                 ichdr.holes = 1;        /* mark as needing compaction */
2006         }
2007         xfs_attr3_leaf_hdr_to_disk(args->geo, leaf, &ichdr);
2008         xfs_trans_log_buf(args->trans, bp,
2009                           XFS_DA_LOGRANGE(leaf, &leaf->hdr,
2010                                           xfs_attr3_leaf_hdr_size(leaf)));
2011
2012         /*
2013          * Check if leaf is less than 50% full, caller may want to
2014          * "join" the leaf with a sibling if so.
2015          */
2016         tmp = ichdr.usedbytes + xfs_attr3_leaf_hdr_size(leaf) +
2017               ichdr.count * sizeof(xfs_attr_leaf_entry_t);
2018
2019         return tmp < args->geo->magicpct; /* leaf is < 37% full */
2020 }
2021
2022 /*
2023  * Move all the attribute list entries from drop_leaf into save_leaf.
2024  */
2025 void
2026 xfs_attr3_leaf_unbalance(
2027         struct xfs_da_state     *state,
2028         struct xfs_da_state_blk *drop_blk,
2029         struct xfs_da_state_blk *save_blk)
2030 {
2031         struct xfs_attr_leafblock *drop_leaf = drop_blk->bp->b_addr;
2032         struct xfs_attr_leafblock *save_leaf = save_blk->bp->b_addr;
2033         struct xfs_attr3_icleaf_hdr drophdr;
2034         struct xfs_attr3_icleaf_hdr savehdr;
2035         struct xfs_attr_leaf_entry *entry;
2036
2037         trace_xfs_attr_leaf_unbalance(state->args);
2038
2039         drop_leaf = drop_blk->bp->b_addr;
2040         save_leaf = save_blk->bp->b_addr;
2041         xfs_attr3_leaf_hdr_from_disk(state->args->geo, &drophdr, drop_leaf);
2042         xfs_attr3_leaf_hdr_from_disk(state->args->geo, &savehdr, save_leaf);
2043         entry = xfs_attr3_leaf_entryp(drop_leaf);
2044
2045         /*
2046          * Save last hashval from dying block for later Btree fixup.
2047          */
2048         drop_blk->hashval = be32_to_cpu(entry[drophdr.count - 1].hashval);
2049
2050         /*
2051          * Check if we need a temp buffer, or can we do it in place.
2052          * Note that we don't check "leaf" for holes because we will
2053          * always be dropping it, toosmall() decided that for us already.
2054          */
2055         if (savehdr.holes == 0) {
2056                 /*
2057                  * dest leaf has no holes, so we add there.  May need
2058                  * to make some room in the entry array.
2059                  */
2060                 if (xfs_attr3_leaf_order(save_blk->bp, &savehdr,
2061                                          drop_blk->bp, &drophdr)) {
2062                         xfs_attr3_leaf_moveents(state->args,
2063                                                 drop_leaf, &drophdr, 0,
2064                                                 save_leaf, &savehdr, 0,
2065                                                 drophdr.count);
2066                 } else {
2067                         xfs_attr3_leaf_moveents(state->args,
2068                                                 drop_leaf, &drophdr, 0,
2069                                                 save_leaf, &savehdr,
2070                                                 savehdr.count, drophdr.count);
2071                 }
2072         } else {
2073                 /*
2074                  * Destination has holes, so we make a temporary copy
2075                  * of the leaf and add them both to that.
2076                  */
2077                 struct xfs_attr_leafblock *tmp_leaf;
2078                 struct xfs_attr3_icleaf_hdr tmphdr;
2079
2080                 tmp_leaf = kmem_zalloc(state->args->geo->blksize, KM_SLEEP);
2081
2082                 /*
2083                  * Copy the header into the temp leaf so that all the stuff
2084                  * not in the incore header is present and gets copied back in
2085                  * once we've moved all the entries.
2086                  */
2087                 memcpy(tmp_leaf, save_leaf, xfs_attr3_leaf_hdr_size(save_leaf));
2088
2089                 memset(&tmphdr, 0, sizeof(tmphdr));
2090                 tmphdr.magic = savehdr.magic;
2091                 tmphdr.forw = savehdr.forw;
2092                 tmphdr.back = savehdr.back;
2093                 tmphdr.firstused = state->args->geo->blksize;
2094
2095                 /* write the header to the temp buffer to initialise it */
2096                 xfs_attr3_leaf_hdr_to_disk(state->args->geo, tmp_leaf, &tmphdr);
2097
2098                 if (xfs_attr3_leaf_order(save_blk->bp, &savehdr,
2099                                          drop_blk->bp, &drophdr)) {
2100                         xfs_attr3_leaf_moveents(state->args,
2101                                                 drop_leaf, &drophdr, 0,
2102                                                 tmp_leaf, &tmphdr, 0,
2103                                                 drophdr.count);
2104                         xfs_attr3_leaf_moveents(state->args,
2105                                                 save_leaf, &savehdr, 0,
2106                                                 tmp_leaf, &tmphdr, tmphdr.count,
2107                                                 savehdr.count);
2108                 } else {
2109                         xfs_attr3_leaf_moveents(state->args,
2110                                                 save_leaf, &savehdr, 0,
2111                                                 tmp_leaf, &tmphdr, 0,
2112                                                 savehdr.count);
2113                         xfs_attr3_leaf_moveents(state->args,
2114                                                 drop_leaf, &drophdr, 0,
2115                                                 tmp_leaf, &tmphdr, tmphdr.count,
2116                                                 drophdr.count);
2117                 }
2118                 memcpy(save_leaf, tmp_leaf, state->args->geo->blksize);
2119                 savehdr = tmphdr; /* struct copy */
2120                 kmem_free(tmp_leaf);
2121         }
2122
2123         xfs_attr3_leaf_hdr_to_disk(state->args->geo, save_leaf, &savehdr);
2124         xfs_trans_log_buf(state->args->trans, save_blk->bp, 0,
2125                                            state->args->geo->blksize - 1);
2126
2127         /*
2128          * Copy out last hashval in each block for B-tree code.
2129          */
2130         entry = xfs_attr3_leaf_entryp(save_leaf);
2131         save_blk->hashval = be32_to_cpu(entry[savehdr.count - 1].hashval);
2132 }
2133
2134 /*========================================================================
2135  * Routines used for finding things in the Btree.
2136  *========================================================================*/
2137
2138 /*
2139  * Look up a name in a leaf attribute list structure.
2140  * This is the internal routine, it uses the caller's buffer.
2141  *
2142  * Note that duplicate keys are allowed, but only check within the
2143  * current leaf node.  The Btree code must check in adjacent leaf nodes.
2144  *
2145  * Return in args->index the index into the entry[] array of either
2146  * the found entry, or where the entry should have been (insert before
2147  * that entry).
2148  *
2149  * Don't change the args->value unless we find the attribute.
2150  */
2151 int
2152 xfs_attr3_leaf_lookup_int(
2153         struct xfs_buf          *bp,
2154         struct xfs_da_args      *args)
2155 {
2156         struct xfs_attr_leafblock *leaf;
2157         struct xfs_attr3_icleaf_hdr ichdr;
2158         struct xfs_attr_leaf_entry *entry;
2159         struct xfs_attr_leaf_entry *entries;
2160         struct xfs_attr_leaf_name_local *name_loc;
2161         struct xfs_attr_leaf_name_remote *name_rmt;
2162         xfs_dahash_t            hashval;
2163         int                     probe;
2164         int                     span;
2165
2166         trace_xfs_attr_leaf_lookup(args);
2167
2168         leaf = bp->b_addr;
2169         xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2170         entries = xfs_attr3_leaf_entryp(leaf);
2171         ASSERT(ichdr.count < args->geo->blksize / 8);
2172
2173         /*
2174          * Binary search.  (note: small blocks will skip this loop)
2175          */
2176         hashval = args->hashval;
2177         probe = span = ichdr.count / 2;
2178         for (entry = &entries[probe]; span > 4; entry = &entries[probe]) {
2179                 span /= 2;
2180                 if (be32_to_cpu(entry->hashval) < hashval)
2181                         probe += span;
2182                 else if (be32_to_cpu(entry->hashval) > hashval)
2183                         probe -= span;
2184                 else
2185                         break;
2186         }
2187         ASSERT(probe >= 0 && (!ichdr.count || probe < ichdr.count));
2188         ASSERT(span <= 4 || be32_to_cpu(entry->hashval) == hashval);
2189
2190         /*
2191          * Since we may have duplicate hashval's, find the first matching
2192          * hashval in the leaf.
2193          */
2194         while (probe > 0 && be32_to_cpu(entry->hashval) >= hashval) {
2195                 entry--;
2196                 probe--;
2197         }
2198         while (probe < ichdr.count &&
2199                be32_to_cpu(entry->hashval) < hashval) {
2200                 entry++;
2201                 probe++;
2202         }
2203         if (probe == ichdr.count || be32_to_cpu(entry->hashval) != hashval) {
2204                 args->index = probe;
2205                 return -ENOATTR;
2206         }
2207
2208         /*
2209          * Duplicate keys may be present, so search all of them for a match.
2210          */
2211         for (; probe < ichdr.count && (be32_to_cpu(entry->hashval) == hashval);
2212                         entry++, probe++) {
2213 /*
2214  * GROT: Add code to remove incomplete entries.
2215  */
2216                 /*
2217                  * If we are looking for INCOMPLETE entries, show only those.
2218                  * If we are looking for complete entries, show only those.
2219                  */
2220                 if ((args->flags & XFS_ATTR_INCOMPLETE) !=
2221                     (entry->flags & XFS_ATTR_INCOMPLETE)) {
2222                         continue;
2223                 }
2224                 if (entry->flags & XFS_ATTR_LOCAL) {
2225                         name_loc = xfs_attr3_leaf_name_local(leaf, probe);
2226                         if (name_loc->namelen != args->namelen)
2227                                 continue;
2228                         if (memcmp(args->name, name_loc->nameval,
2229                                                         args->namelen) != 0)
2230                                 continue;
2231                         if (!xfs_attr_namesp_match(args->flags, entry->flags))
2232                                 continue;
2233                         args->index = probe;
2234                         return -EEXIST;
2235                 } else {
2236                         name_rmt = xfs_attr3_leaf_name_remote(leaf, probe);
2237                         if (name_rmt->namelen != args->namelen)
2238                                 continue;
2239                         if (memcmp(args->name, name_rmt->name,
2240                                                         args->namelen) != 0)
2241                                 continue;
2242                         if (!xfs_attr_namesp_match(args->flags, entry->flags))
2243                                 continue;
2244                         args->index = probe;
2245                         args->rmtvaluelen = be32_to_cpu(name_rmt->valuelen);
2246                         args->rmtblkno = be32_to_cpu(name_rmt->valueblk);
2247                         args->rmtblkcnt = xfs_attr3_rmt_blocks(
2248                                                         args->dp->i_mount,
2249                                                         args->rmtvaluelen);
2250                         return -EEXIST;
2251                 }
2252         }
2253         args->index = probe;
2254         return -ENOATTR;
2255 }
2256
2257 /*
2258  * Get the value associated with an attribute name from a leaf attribute
2259  * list structure.
2260  */
2261 int
2262 xfs_attr3_leaf_getvalue(
2263         struct xfs_buf          *bp,
2264         struct xfs_da_args      *args)
2265 {
2266         struct xfs_attr_leafblock *leaf;
2267         struct xfs_attr3_icleaf_hdr ichdr;
2268         struct xfs_attr_leaf_entry *entry;
2269         struct xfs_attr_leaf_name_local *name_loc;
2270         struct xfs_attr_leaf_name_remote *name_rmt;
2271         int                     valuelen;
2272
2273         leaf = bp->b_addr;
2274         xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2275         ASSERT(ichdr.count < args->geo->blksize / 8);
2276         ASSERT(args->index < ichdr.count);
2277
2278         entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
2279         if (entry->flags & XFS_ATTR_LOCAL) {
2280                 name_loc = xfs_attr3_leaf_name_local(leaf, args->index);
2281                 ASSERT(name_loc->namelen == args->namelen);
2282                 ASSERT(memcmp(args->name, name_loc->nameval, args->namelen) == 0);
2283                 valuelen = be16_to_cpu(name_loc->valuelen);
2284                 if (args->flags & ATTR_KERNOVAL) {
2285                         args->valuelen = valuelen;
2286                         return 0;
2287                 }
2288                 if (args->valuelen < valuelen) {
2289                         args->valuelen = valuelen;
2290                         return -ERANGE;
2291                 }
2292                 args->valuelen = valuelen;
2293                 memcpy(args->value, &name_loc->nameval[args->namelen], valuelen);
2294         } else {
2295                 name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2296                 ASSERT(name_rmt->namelen == args->namelen);
2297                 ASSERT(memcmp(args->name, name_rmt->name, args->namelen) == 0);
2298                 args->rmtvaluelen = be32_to_cpu(name_rmt->valuelen);
2299                 args->rmtblkno = be32_to_cpu(name_rmt->valueblk);
2300                 args->rmtblkcnt = xfs_attr3_rmt_blocks(args->dp->i_mount,
2301                                                        args->rmtvaluelen);
2302                 if (args->flags & ATTR_KERNOVAL) {
2303                         args->valuelen = args->rmtvaluelen;
2304                         return 0;
2305                 }
2306                 if (args->valuelen < args->rmtvaluelen) {
2307                         args->valuelen = args->rmtvaluelen;
2308                         return -ERANGE;
2309                 }
2310                 args->valuelen = args->rmtvaluelen;
2311         }
2312         return 0;
2313 }
2314
2315 /*========================================================================
2316  * Utility routines.
2317  *========================================================================*/
2318
2319 /*
2320  * Move the indicated entries from one leaf to another.
2321  * NOTE: this routine modifies both source and destination leaves.
2322  */
2323 /*ARGSUSED*/
2324 STATIC void
2325 xfs_attr3_leaf_moveents(
2326         struct xfs_da_args              *args,
2327         struct xfs_attr_leafblock       *leaf_s,
2328         struct xfs_attr3_icleaf_hdr     *ichdr_s,
2329         int                             start_s,
2330         struct xfs_attr_leafblock       *leaf_d,
2331         struct xfs_attr3_icleaf_hdr     *ichdr_d,
2332         int                             start_d,
2333         int                             count)
2334 {
2335         struct xfs_attr_leaf_entry      *entry_s;
2336         struct xfs_attr_leaf_entry      *entry_d;
2337         int                             desti;
2338         int                             tmp;
2339         int                             i;
2340
2341         /*
2342          * Check for nothing to do.
2343          */
2344         if (count == 0)
2345                 return;
2346
2347         /*
2348          * Set up environment.
2349          */
2350         ASSERT(ichdr_s->magic == XFS_ATTR_LEAF_MAGIC ||
2351                ichdr_s->magic == XFS_ATTR3_LEAF_MAGIC);
2352         ASSERT(ichdr_s->magic == ichdr_d->magic);
2353         ASSERT(ichdr_s->count > 0 && ichdr_s->count < args->geo->blksize / 8);
2354         ASSERT(ichdr_s->firstused >= (ichdr_s->count * sizeof(*entry_s))
2355                                         + xfs_attr3_leaf_hdr_size(leaf_s));
2356         ASSERT(ichdr_d->count < args->geo->blksize / 8);
2357         ASSERT(ichdr_d->firstused >= (ichdr_d->count * sizeof(*entry_d))
2358                                         + xfs_attr3_leaf_hdr_size(leaf_d));
2359
2360         ASSERT(start_s < ichdr_s->count);
2361         ASSERT(start_d <= ichdr_d->count);
2362         ASSERT(count <= ichdr_s->count);
2363
2364
2365         /*
2366          * Move the entries in the destination leaf up to make a hole?
2367          */
2368         if (start_d < ichdr_d->count) {
2369                 tmp  = ichdr_d->count - start_d;
2370                 tmp *= sizeof(xfs_attr_leaf_entry_t);
2371                 entry_s = &xfs_attr3_leaf_entryp(leaf_d)[start_d];
2372                 entry_d = &xfs_attr3_leaf_entryp(leaf_d)[start_d + count];
2373                 memmove(entry_d, entry_s, tmp);
2374         }
2375
2376         /*
2377          * Copy all entry's in the same (sorted) order,
2378          * but allocate attribute info packed and in sequence.
2379          */
2380         entry_s = &xfs_attr3_leaf_entryp(leaf_s)[start_s];
2381         entry_d = &xfs_attr3_leaf_entryp(leaf_d)[start_d];
2382         desti = start_d;
2383         for (i = 0; i < count; entry_s++, entry_d++, desti++, i++) {
2384                 ASSERT(be16_to_cpu(entry_s->nameidx) >= ichdr_s->firstused);
2385                 tmp = xfs_attr_leaf_entsize(leaf_s, start_s + i);
2386 #ifdef GROT
2387                 /*
2388                  * Code to drop INCOMPLETE entries.  Difficult to use as we
2389                  * may also need to change the insertion index.  Code turned
2390                  * off for 6.2, should be revisited later.
2391                  */
2392                 if (entry_s->flags & XFS_ATTR_INCOMPLETE) { /* skip partials? */
2393                         memset(xfs_attr3_leaf_name(leaf_s, start_s + i), 0, tmp);
2394                         ichdr_s->usedbytes -= tmp;
2395                         ichdr_s->count -= 1;
2396                         entry_d--;      /* to compensate for ++ in loop hdr */
2397                         desti--;
2398                         if ((start_s + i) < offset)
2399                                 result++;       /* insertion index adjustment */
2400                 } else {
2401 #endif /* GROT */
2402                         ichdr_d->firstused -= tmp;
2403                         /* both on-disk, don't endian flip twice */
2404                         entry_d->hashval = entry_s->hashval;
2405                         entry_d->nameidx = cpu_to_be16(ichdr_d->firstused);
2406                         entry_d->flags = entry_s->flags;
2407                         ASSERT(be16_to_cpu(entry_d->nameidx) + tmp
2408                                                         <= args->geo->blksize);
2409                         memmove(xfs_attr3_leaf_name(leaf_d, desti),
2410                                 xfs_attr3_leaf_name(leaf_s, start_s + i), tmp);
2411                         ASSERT(be16_to_cpu(entry_s->nameidx) + tmp
2412                                                         <= args->geo->blksize);
2413                         memset(xfs_attr3_leaf_name(leaf_s, start_s + i), 0, tmp);
2414                         ichdr_s->usedbytes -= tmp;
2415                         ichdr_d->usedbytes += tmp;
2416                         ichdr_s->count -= 1;
2417                         ichdr_d->count += 1;
2418                         tmp = ichdr_d->count * sizeof(xfs_attr_leaf_entry_t)
2419                                         + xfs_attr3_leaf_hdr_size(leaf_d);
2420                         ASSERT(ichdr_d->firstused >= tmp);
2421 #ifdef GROT
2422                 }
2423 #endif /* GROT */
2424         }
2425
2426         /*
2427          * Zero out the entries we just copied.
2428          */
2429         if (start_s == ichdr_s->count) {
2430                 tmp = count * sizeof(xfs_attr_leaf_entry_t);
2431                 entry_s = &xfs_attr3_leaf_entryp(leaf_s)[start_s];
2432                 ASSERT(((char *)entry_s + tmp) <=
2433                        ((char *)leaf_s + args->geo->blksize));
2434                 memset(entry_s, 0, tmp);
2435         } else {
2436                 /*
2437                  * Move the remaining entries down to fill the hole,
2438                  * then zero the entries at the top.
2439                  */
2440                 tmp  = (ichdr_s->count - count) * sizeof(xfs_attr_leaf_entry_t);
2441                 entry_s = &xfs_attr3_leaf_entryp(leaf_s)[start_s + count];
2442                 entry_d = &xfs_attr3_leaf_entryp(leaf_s)[start_s];
2443                 memmove(entry_d, entry_s, tmp);
2444
2445                 tmp = count * sizeof(xfs_attr_leaf_entry_t);
2446                 entry_s = &xfs_attr3_leaf_entryp(leaf_s)[ichdr_s->count];
2447                 ASSERT(((char *)entry_s + tmp) <=
2448                        ((char *)leaf_s + args->geo->blksize));
2449                 memset(entry_s, 0, tmp);
2450         }
2451
2452         /*
2453          * Fill in the freemap information
2454          */
2455         ichdr_d->freemap[0].base = xfs_attr3_leaf_hdr_size(leaf_d);
2456         ichdr_d->freemap[0].base += ichdr_d->count * sizeof(xfs_attr_leaf_entry_t);
2457         ichdr_d->freemap[0].size = ichdr_d->firstused - ichdr_d->freemap[0].base;
2458         ichdr_d->freemap[1].base = 0;
2459         ichdr_d->freemap[2].base = 0;
2460         ichdr_d->freemap[1].size = 0;
2461         ichdr_d->freemap[2].size = 0;
2462         ichdr_s->holes = 1;     /* leaf may not be compact */
2463 }
2464
2465 /*
2466  * Pick up the last hashvalue from a leaf block.
2467  */
2468 xfs_dahash_t
2469 xfs_attr_leaf_lasthash(
2470         struct xfs_buf  *bp,
2471         int             *count)
2472 {
2473         struct xfs_attr3_icleaf_hdr ichdr;
2474         struct xfs_attr_leaf_entry *entries;
2475         struct xfs_mount *mp = bp->b_target->bt_mount;
2476
2477         xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, bp->b_addr);
2478         entries = xfs_attr3_leaf_entryp(bp->b_addr);
2479         if (count)
2480                 *count = ichdr.count;
2481         if (!ichdr.count)
2482                 return 0;
2483         return be32_to_cpu(entries[ichdr.count - 1].hashval);
2484 }
2485
2486 /*
2487  * Calculate the number of bytes used to store the indicated attribute
2488  * (whether local or remote only calculate bytes in this block).
2489  */
2490 STATIC int
2491 xfs_attr_leaf_entsize(xfs_attr_leafblock_t *leaf, int index)
2492 {
2493         struct xfs_attr_leaf_entry *entries;
2494         xfs_attr_leaf_name_local_t *name_loc;
2495         xfs_attr_leaf_name_remote_t *name_rmt;
2496         int size;
2497
2498         entries = xfs_attr3_leaf_entryp(leaf);
2499         if (entries[index].flags & XFS_ATTR_LOCAL) {
2500                 name_loc = xfs_attr3_leaf_name_local(leaf, index);
2501                 size = xfs_attr_leaf_entsize_local(name_loc->namelen,
2502                                                    be16_to_cpu(name_loc->valuelen));
2503         } else {
2504                 name_rmt = xfs_attr3_leaf_name_remote(leaf, index);
2505                 size = xfs_attr_leaf_entsize_remote(name_rmt->namelen);
2506         }
2507         return size;
2508 }
2509
2510 /*
2511  * Calculate the number of bytes that would be required to store the new
2512  * attribute (whether local or remote only calculate bytes in this block).
2513  * This routine decides as a side effect whether the attribute will be
2514  * a "local" or a "remote" attribute.
2515  */
2516 int
2517 xfs_attr_leaf_newentsize(
2518         struct xfs_da_args      *args,
2519         int                     *local)
2520 {
2521         int                     size;
2522
2523         size = xfs_attr_leaf_entsize_local(args->namelen, args->valuelen);
2524         if (size < xfs_attr_leaf_entsize_local_max(args->geo->blksize)) {
2525                 if (local)
2526                         *local = 1;
2527                 return size;
2528         }
2529         if (local)
2530                 *local = 0;
2531         return xfs_attr_leaf_entsize_remote(args->namelen);
2532 }
2533
2534
2535 /*========================================================================
2536  * Manage the INCOMPLETE flag in a leaf entry
2537  *========================================================================*/
2538
2539 /*
2540  * Clear the INCOMPLETE flag on an entry in a leaf block.
2541  */
2542 int
2543 xfs_attr3_leaf_clearflag(
2544         struct xfs_da_args      *args)
2545 {
2546         struct xfs_attr_leafblock *leaf;
2547         struct xfs_attr_leaf_entry *entry;
2548         struct xfs_attr_leaf_name_remote *name_rmt;
2549         struct xfs_buf          *bp;
2550         int                     error;
2551 #ifdef DEBUG
2552         struct xfs_attr3_icleaf_hdr ichdr;
2553         xfs_attr_leaf_name_local_t *name_loc;
2554         int namelen;
2555         char *name;
2556 #endif /* DEBUG */
2557
2558         trace_xfs_attr_leaf_clearflag(args);
2559         /*
2560          * Set up the operation.
2561          */
2562         error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
2563         if (error)
2564                 return error;
2565
2566         leaf = bp->b_addr;
2567         entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
2568         ASSERT(entry->flags & XFS_ATTR_INCOMPLETE);
2569
2570 #ifdef DEBUG
2571         xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2572         ASSERT(args->index < ichdr.count);
2573         ASSERT(args->index >= 0);
2574
2575         if (entry->flags & XFS_ATTR_LOCAL) {
2576                 name_loc = xfs_attr3_leaf_name_local(leaf, args->index);
2577                 namelen = name_loc->namelen;
2578                 name = (char *)name_loc->nameval;
2579         } else {
2580                 name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2581                 namelen = name_rmt->namelen;
2582                 name = (char *)name_rmt->name;
2583         }
2584         ASSERT(be32_to_cpu(entry->hashval) == args->hashval);
2585         ASSERT(namelen == args->namelen);
2586         ASSERT(memcmp(name, args->name, namelen) == 0);
2587 #endif /* DEBUG */
2588
2589         entry->flags &= ~XFS_ATTR_INCOMPLETE;
2590         xfs_trans_log_buf(args->trans, bp,
2591                          XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));
2592
2593         if (args->rmtblkno) {
2594                 ASSERT((entry->flags & XFS_ATTR_LOCAL) == 0);
2595                 name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2596                 name_rmt->valueblk = cpu_to_be32(args->rmtblkno);
2597                 name_rmt->valuelen = cpu_to_be32(args->rmtvaluelen);
2598                 xfs_trans_log_buf(args->trans, bp,
2599                          XFS_DA_LOGRANGE(leaf, name_rmt, sizeof(*name_rmt)));
2600         }
2601
2602         /*
2603          * Commit the flag value change and start the next trans in series.
2604          */
2605         return xfs_trans_roll(&args->trans, args->dp);
2606 }
2607
2608 /*
2609  * Set the INCOMPLETE flag on an entry in a leaf block.
2610  */
2611 int
2612 xfs_attr3_leaf_setflag(
2613         struct xfs_da_args      *args)
2614 {
2615         struct xfs_attr_leafblock *leaf;
2616         struct xfs_attr_leaf_entry *entry;
2617         struct xfs_attr_leaf_name_remote *name_rmt;
2618         struct xfs_buf          *bp;
2619         int error;
2620 #ifdef DEBUG
2621         struct xfs_attr3_icleaf_hdr ichdr;
2622 #endif
2623
2624         trace_xfs_attr_leaf_setflag(args);
2625
2626         /*
2627          * Set up the operation.
2628          */
2629         error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
2630         if (error)
2631                 return error;
2632
2633         leaf = bp->b_addr;
2634 #ifdef DEBUG
2635         xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
2636         ASSERT(args->index < ichdr.count);
2637         ASSERT(args->index >= 0);
2638 #endif
2639         entry = &xfs_attr3_leaf_entryp(leaf)[args->index];
2640
2641         ASSERT((entry->flags & XFS_ATTR_INCOMPLETE) == 0);
2642         entry->flags |= XFS_ATTR_INCOMPLETE;
2643         xfs_trans_log_buf(args->trans, bp,
2644                         XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));
2645         if ((entry->flags & XFS_ATTR_LOCAL) == 0) {
2646                 name_rmt = xfs_attr3_leaf_name_remote(leaf, args->index);
2647                 name_rmt->valueblk = 0;
2648                 name_rmt->valuelen = 0;
2649                 xfs_trans_log_buf(args->trans, bp,
2650                          XFS_DA_LOGRANGE(leaf, name_rmt, sizeof(*name_rmt)));
2651         }
2652
2653         /*
2654          * Commit the flag value change and start the next trans in series.
2655          */
2656         return xfs_trans_roll(&args->trans, args->dp);
2657 }
2658
2659 /*
2660  * In a single transaction, clear the INCOMPLETE flag on the leaf entry
2661  * given by args->blkno/index and set the INCOMPLETE flag on the leaf
2662  * entry given by args->blkno2/index2.
2663  *
2664  * Note that they could be in different blocks, or in the same block.
2665  */
2666 int
2667 xfs_attr3_leaf_flipflags(
2668         struct xfs_da_args      *args)
2669 {
2670         struct xfs_attr_leafblock *leaf1;
2671         struct xfs_attr_leafblock *leaf2;
2672         struct xfs_attr_leaf_entry *entry1;
2673         struct xfs_attr_leaf_entry *entry2;
2674         struct xfs_attr_leaf_name_remote *name_rmt;
2675         struct xfs_buf          *bp1;
2676         struct xfs_buf          *bp2;
2677         int error;
2678 #ifdef DEBUG
2679         struct xfs_attr3_icleaf_hdr ichdr1;
2680         struct xfs_attr3_icleaf_hdr ichdr2;
2681         xfs_attr_leaf_name_local_t *name_loc;
2682         int namelen1, namelen2;
2683         char *name1, *name2;
2684 #endif /* DEBUG */
2685
2686         trace_xfs_attr_leaf_flipflags(args);
2687
2688         /*
2689          * Read the block containing the "old" attr
2690          */
2691         error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp1);
2692         if (error)
2693                 return error;
2694
2695         /*
2696          * Read the block containing the "new" attr, if it is different
2697          */
2698         if (args->blkno2 != args->blkno) {
2699                 error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno2,
2700                                            -1, &bp2);
2701                 if (error)
2702                         return error;
2703         } else {
2704                 bp2 = bp1;
2705         }
2706
2707         leaf1 = bp1->b_addr;
2708         entry1 = &xfs_attr3_leaf_entryp(leaf1)[args->index];
2709
2710         leaf2 = bp2->b_addr;
2711         entry2 = &xfs_attr3_leaf_entryp(leaf2)[args->index2];
2712
2713 #ifdef DEBUG
2714         xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr1, leaf1);
2715         ASSERT(args->index < ichdr1.count);
2716         ASSERT(args->index >= 0);
2717
2718         xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr2, leaf2);
2719         ASSERT(args->index2 < ichdr2.count);
2720         ASSERT(args->index2 >= 0);
2721
2722         if (entry1->flags & XFS_ATTR_LOCAL) {
2723                 name_loc = xfs_attr3_leaf_name_local(leaf1, args->index);
2724                 namelen1 = name_loc->namelen;
2725                 name1 = (char *)name_loc->nameval;
2726         } else {
2727                 name_rmt = xfs_attr3_leaf_name_remote(leaf1, args->index);
2728                 namelen1 = name_rmt->namelen;
2729                 name1 = (char *)name_rmt->name;
2730         }
2731         if (entry2->flags & XFS_ATTR_LOCAL) {
2732                 name_loc = xfs_attr3_leaf_name_local(leaf2, args->index2);
2733                 namelen2 = name_loc->namelen;
2734                 name2 = (char *)name_loc->nameval;
2735         } else {
2736                 name_rmt = xfs_attr3_leaf_name_remote(leaf2, args->index2);
2737                 namelen2 = name_rmt->namelen;
2738                 name2 = (char *)name_rmt->name;
2739         }
2740         ASSERT(be32_to_cpu(entry1->hashval) == be32_to_cpu(entry2->hashval));
2741         ASSERT(namelen1 == namelen2);
2742         ASSERT(memcmp(name1, name2, namelen1) == 0);
2743 #endif /* DEBUG */
2744
2745         ASSERT(entry1->flags & XFS_ATTR_INCOMPLETE);
2746         ASSERT((entry2->flags & XFS_ATTR_INCOMPLETE) == 0);
2747
2748         entry1->flags &= ~XFS_ATTR_INCOMPLETE;
2749         xfs_trans_log_buf(args->trans, bp1,
2750                           XFS_DA_LOGRANGE(leaf1, entry1, sizeof(*entry1)));
2751         if (args->rmtblkno) {
2752                 ASSERT((entry1->flags & XFS_ATTR_LOCAL) == 0);
2753                 name_rmt = xfs_attr3_leaf_name_remote(leaf1, args->index);
2754                 name_rmt->valueblk = cpu_to_be32(args->rmtblkno);
2755                 name_rmt->valuelen = cpu_to_be32(args->rmtvaluelen);
2756                 xfs_trans_log_buf(args->trans, bp1,
2757                          XFS_DA_LOGRANGE(leaf1, name_rmt, sizeof(*name_rmt)));
2758         }
2759
2760         entry2->flags |= XFS_ATTR_INCOMPLETE;
2761         xfs_trans_log_buf(args->trans, bp2,
2762                           XFS_DA_LOGRANGE(leaf2, entry2, sizeof(*entry2)));
2763         if ((entry2->flags & XFS_ATTR_LOCAL) == 0) {
2764                 name_rmt = xfs_attr3_leaf_name_remote(leaf2, args->index2);
2765                 name_rmt->valueblk = 0;
2766                 name_rmt->valuelen = 0;
2767                 xfs_trans_log_buf(args->trans, bp2,
2768                          XFS_DA_LOGRANGE(leaf2, name_rmt, sizeof(*name_rmt)));
2769         }
2770
2771         /*
2772          * Commit the flag value change and start the next trans in series.
2773          */
2774         error = xfs_trans_roll(&args->trans, args->dp);
2775
2776         return error;
2777 }