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Merge tag 'arc-v3.13-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux/fpc-iii.git] / fs / xfs / xfs_da_btree.c
blob796272a2e1298fca3a5cc08ef4c6b226d6eec15c
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_ag.h"
28 #include "xfs_mount.h"
29 #include "xfs_da_format.h"
30 #include "xfs_da_btree.h"
31 #include "xfs_dir2.h"
32 #include "xfs_dir2_priv.h"
33 #include "xfs_inode.h"
34 #include "xfs_trans.h"
35 #include "xfs_inode_item.h"
36 #include "xfs_alloc.h"
37 #include "xfs_bmap.h"
38 #include "xfs_attr.h"
39 #include "xfs_attr_leaf.h"
40 #include "xfs_error.h"
41 #include "xfs_trace.h"
42 #include "xfs_cksum.h"
43 #include "xfs_buf_item.h"
44
45 /*
46 * xfs_da_btree.c
47 *
48 * Routines to implement directories as Btrees of hashed names.
49 */
50
51 /*========================================================================
52 * Function prototypes for the kernel.
53 *========================================================================*/
54
55 /*
56 * Routines used for growing the Btree.
57 */
58 STATIC int xfs_da3_root_split(xfs_da_state_t *state,
59 xfs_da_state_blk_t *existing_root,
60 xfs_da_state_blk_t *new_child);
61 STATIC int xfs_da3_node_split(xfs_da_state_t *state,
62 xfs_da_state_blk_t *existing_blk,
63 xfs_da_state_blk_t *split_blk,
64 xfs_da_state_blk_t *blk_to_add,
65 int treelevel,
66 int *result);
67 STATIC void xfs_da3_node_rebalance(xfs_da_state_t *state,
68 xfs_da_state_blk_t *node_blk_1,
69 xfs_da_state_blk_t *node_blk_2);
70 STATIC void xfs_da3_node_add(xfs_da_state_t *state,
71 xfs_da_state_blk_t *old_node_blk,
72 xfs_da_state_blk_t *new_node_blk);
73
74 /*
75 * Routines used for shrinking the Btree.
76 */
77 STATIC int xfs_da3_root_join(xfs_da_state_t *state,
78 xfs_da_state_blk_t *root_blk);
79 STATIC int xfs_da3_node_toosmall(xfs_da_state_t *state, int *retval);
80 STATIC void xfs_da3_node_remove(xfs_da_state_t *state,
81 xfs_da_state_blk_t *drop_blk);
82 STATIC void xfs_da3_node_unbalance(xfs_da_state_t *state,
83 xfs_da_state_blk_t *src_node_blk,
84 xfs_da_state_blk_t *dst_node_blk);
85
86 /*
87 * Utility routines.
88 */
89 STATIC int xfs_da3_blk_unlink(xfs_da_state_t *state,
90 xfs_da_state_blk_t *drop_blk,
91 xfs_da_state_blk_t *save_blk);
92
93
94 kmem_zone_t *xfs_da_state_zone; /* anchor for state struct zone */
95
96 /*
97 * Allocate a dir-state structure.
98 * We don't put them on the stack since they're large.
99 */
100 xfs_da_state_t *
101 xfs_da_state_alloc(void)
102 {
103 return kmem_zone_zalloc(xfs_da_state_zone, KM_NOFS);
104 }
105
106 /*
107 * Kill the altpath contents of a da-state structure.
108 */
109 STATIC void
110 xfs_da_state_kill_altpath(xfs_da_state_t *state)
111 {
112 int i;
113
114 for (i = 0; i < state->altpath.active; i++)
115 state->altpath.blk[i].bp = NULL;
116 state->altpath.active = 0;
117 }
118
119 /*
120 * Free a da-state structure.
121 */
122 void
123 xfs_da_state_free(xfs_da_state_t *state)
124 {
125 xfs_da_state_kill_altpath(state);
126 #ifdef DEBUG
127 memset((char *)state, 0, sizeof(*state));
128 #endif /* DEBUG */
129 kmem_zone_free(xfs_da_state_zone, state);
130 }
131
132 static bool
133 xfs_da3_node_verify(
134 struct xfs_buf *bp)
135 {
136 struct xfs_mount *mp = bp->b_target->bt_mount;
137 struct xfs_da_intnode *hdr = bp->b_addr;
138 struct xfs_da3_icnode_hdr ichdr;
139 const struct xfs_dir_ops *ops;
140
141 ops = xfs_dir_get_ops(mp, NULL);
142
143 ops->node_hdr_from_disk(&ichdr, hdr);
144
145 if (xfs_sb_version_hascrc(&mp->m_sb)) {
146 struct xfs_da3_node_hdr *hdr3 = bp->b_addr;
147
148 if (ichdr.magic != XFS_DA3_NODE_MAGIC)
149 return false;
150
151 if (!uuid_equal(&hdr3->info.uuid, &mp->m_sb.sb_uuid))
152 return false;
153 if (be64_to_cpu(hdr3->info.blkno) != bp->b_bn)
154 return false;
155 } else {
156 if (ichdr.magic != XFS_DA_NODE_MAGIC)
157 return false;
158 }
159 if (ichdr.level == 0)
160 return false;
161 if (ichdr.level > XFS_DA_NODE_MAXDEPTH)
162 return false;
163 if (ichdr.count == 0)
164 return false;
165
166 /*
167 * we don't know if the node is for and attribute or directory tree,
168 * so only fail if the count is outside both bounds
169 */
170 if (ichdr.count > mp->m_dir_node_ents &&
171 ichdr.count > mp->m_attr_node_ents)
172 return false;
173
174 /* XXX: hash order check? */
175
176 return true;
177 }
178
179 static void
180 xfs_da3_node_write_verify(
181 struct xfs_buf *bp)
182 {
183 struct xfs_mount *mp = bp->b_target->bt_mount;
184 struct xfs_buf_log_item *bip = bp->b_fspriv;
185 struct xfs_da3_node_hdr *hdr3 = bp->b_addr;
186
187 if (!xfs_da3_node_verify(bp)) {
188 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
189 xfs_buf_ioerror(bp, EFSCORRUPTED);
190 return;
191 }
192
193 if (!xfs_sb_version_hascrc(&mp->m_sb))
194 return;
195
196 if (bip)
197 hdr3->info.lsn = cpu_to_be64(bip->bli_item.li_lsn);
198
199 xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length), XFS_DA3_NODE_CRC_OFF);
200 }
201
202 /*
203 * leaf/node format detection on trees is sketchy, so a node read can be done on
204 * leaf level blocks when detection identifies the tree as a node format tree
205 * incorrectly. In this case, we need to swap the verifier to match the correct
206 * format of the block being read.
207 */
208 static void
209 xfs_da3_node_read_verify(
210 struct xfs_buf *bp)
211 {
212 struct xfs_mount *mp = bp->b_target->bt_mount;
213 struct xfs_da_blkinfo *info = bp->b_addr;
214
215 switch (be16_to_cpu(info->magic)) {
216 case XFS_DA3_NODE_MAGIC:
217 if (!xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
218 XFS_DA3_NODE_CRC_OFF))
219 break;
220 /* fall through */
221 case XFS_DA_NODE_MAGIC:
222 if (!xfs_da3_node_verify(bp))
223 break;
224 return;
225 case XFS_ATTR_LEAF_MAGIC:
226 case XFS_ATTR3_LEAF_MAGIC:
227 bp->b_ops = &xfs_attr3_leaf_buf_ops;
228 bp->b_ops->verify_read(bp);
229 return;
230 case XFS_DIR2_LEAFN_MAGIC:
231 case XFS_DIR3_LEAFN_MAGIC:
232 bp->b_ops = &xfs_dir3_leafn_buf_ops;
233 bp->b_ops->verify_read(bp);
234 return;
235 default:
236 break;
237 }
238
239 /* corrupt block */
240 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
241 xfs_buf_ioerror(bp, EFSCORRUPTED);
242 }
243
244 const struct xfs_buf_ops xfs_da3_node_buf_ops = {
245 .verify_read = xfs_da3_node_read_verify,
246 .verify_write = xfs_da3_node_write_verify,
247 };
248
249 int
250 xfs_da3_node_read(
251 struct xfs_trans *tp,
252 struct xfs_inode *dp,
253 xfs_dablk_t bno,
254 xfs_daddr_t mappedbno,
255 struct xfs_buf **bpp,
256 int which_fork)
257 {
258 int err;
259
260 err = xfs_da_read_buf(tp, dp, bno, mappedbno, bpp,
261 which_fork, &xfs_da3_node_buf_ops);
262 if (!err && tp) {
263 struct xfs_da_blkinfo *info = (*bpp)->b_addr;
264 int type;
265
266 switch (be16_to_cpu(info->magic)) {
267 case XFS_DA_NODE_MAGIC:
268 case XFS_DA3_NODE_MAGIC:
269 type = XFS_BLFT_DA_NODE_BUF;
270 break;
271 case XFS_ATTR_LEAF_MAGIC:
272 case XFS_ATTR3_LEAF_MAGIC:
273 type = XFS_BLFT_ATTR_LEAF_BUF;
274 break;
275 case XFS_DIR2_LEAFN_MAGIC:
276 case XFS_DIR3_LEAFN_MAGIC:
277 type = XFS_BLFT_DIR_LEAFN_BUF;
278 break;
279 default:
280 type = 0;
281 ASSERT(0);
282 break;
283 }
284 xfs_trans_buf_set_type(tp, *bpp, type);
285 }
286 return err;
287 }
288
289 /*========================================================================
290 * Routines used for growing the Btree.
291 *========================================================================*/
292
293 /*
294 * Create the initial contents of an intermediate node.
295 */
296 int
297 xfs_da3_node_create(
298 struct xfs_da_args *args,
299 xfs_dablk_t blkno,
300 int level,
301 struct xfs_buf **bpp,
302 int whichfork)
303 {
304 struct xfs_da_intnode *node;
305 struct xfs_trans *tp = args->trans;
306 struct xfs_mount *mp = tp->t_mountp;
307 struct xfs_da3_icnode_hdr ichdr = {0};
308 struct xfs_buf *bp;
309 int error;
310 struct xfs_inode *dp = args->dp;
311
312 trace_xfs_da_node_create(args);
313 ASSERT(level <= XFS_DA_NODE_MAXDEPTH);
314
315 error = xfs_da_get_buf(tp, dp, blkno, -1, &bp, whichfork);
316 if (error)
317 return(error);
318 bp->b_ops = &xfs_da3_node_buf_ops;
319 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DA_NODE_BUF);
320 node = bp->b_addr;
321
322 if (xfs_sb_version_hascrc(&mp->m_sb)) {
323 struct xfs_da3_node_hdr *hdr3 = bp->b_addr;
324
325 ichdr.magic = XFS_DA3_NODE_MAGIC;
326 hdr3->info.blkno = cpu_to_be64(bp->b_bn);
327 hdr3->info.owner = cpu_to_be64(args->dp->i_ino);
328 uuid_copy(&hdr3->info.uuid, &mp->m_sb.sb_uuid);
329 } else {
330 ichdr.magic = XFS_DA_NODE_MAGIC;
331 }
332 ichdr.level = level;
333
334 dp->d_ops->node_hdr_to_disk(node, &ichdr);
335 xfs_trans_log_buf(tp, bp,
336 XFS_DA_LOGRANGE(node, &node->hdr, dp->d_ops->node_hdr_size));
337
338 *bpp = bp;
339 return(0);
340 }
341
342 /*
343 * Split a leaf node, rebalance, then possibly split
344 * intermediate nodes, rebalance, etc.
345 */
346 int /* error */
347 xfs_da3_split(
348 struct xfs_da_state *state)
349 {
350 struct xfs_da_state_blk *oldblk;
351 struct xfs_da_state_blk *newblk;
352 struct xfs_da_state_blk *addblk;
353 struct xfs_da_intnode *node;
354 struct xfs_buf *bp;
355 int max;
356 int action = 0;
357 int error;
358 int i;
359
360 trace_xfs_da_split(state->args);
361
362 /*
363 * Walk back up the tree splitting/inserting/adjusting as necessary.
364 * If we need to insert and there isn't room, split the node, then
365 * decide which fragment to insert the new block from below into.
366 * Note that we may split the root this way, but we need more fixup.
367 */
368 max = state->path.active - 1;
369 ASSERT((max >= 0) && (max < XFS_DA_NODE_MAXDEPTH));
370 ASSERT(state->path.blk[max].magic == XFS_ATTR_LEAF_MAGIC ||
371 state->path.blk[max].magic == XFS_DIR2_LEAFN_MAGIC);
372
373 addblk = &state->path.blk[max]; /* initial dummy value */
374 for (i = max; (i >= 0) && addblk; state->path.active--, i--) {
375 oldblk = &state->path.blk[i];
376 newblk = &state->altpath.blk[i];
377
378 /*
379 * If a leaf node then
380 * Allocate a new leaf node, then rebalance across them.
381 * else if an intermediate node then
382 * We split on the last layer, must we split the node?
383 */
384 switch (oldblk->magic) {
385 case XFS_ATTR_LEAF_MAGIC:
386 error = xfs_attr3_leaf_split(state, oldblk, newblk);
387 if ((error != 0) && (error != ENOSPC)) {
388 return(error); /* GROT: attr is inconsistent */
389 }
390 if (!error) {
391 addblk = newblk;
392 break;
393 }
394 /*
395 * Entry wouldn't fit, split the leaf again.
396 */
397 state->extravalid = 1;
398 if (state->inleaf) {
399 state->extraafter = 0; /* before newblk */
400 trace_xfs_attr_leaf_split_before(state->args);
401 error = xfs_attr3_leaf_split(state, oldblk,
402 &state->extrablk);
403 } else {
404 state->extraafter = 1; /* after newblk */
405 trace_xfs_attr_leaf_split_after(state->args);
406 error = xfs_attr3_leaf_split(state, newblk,
407 &state->extrablk);
408 }
409 if (error)
410 return(error); /* GROT: attr inconsistent */
411 addblk = newblk;
412 break;
413 case XFS_DIR2_LEAFN_MAGIC:
414 error = xfs_dir2_leafn_split(state, oldblk, newblk);
415 if (error)
416 return error;
417 addblk = newblk;
418 break;
419 case XFS_DA_NODE_MAGIC:
420 error = xfs_da3_node_split(state, oldblk, newblk, addblk,
421 max - i, &action);
422 addblk->bp = NULL;
423 if (error)
424 return(error); /* GROT: dir is inconsistent */
425 /*
426 * Record the newly split block for the next time thru?
427 */
428 if (action)
429 addblk = newblk;
430 else
431 addblk = NULL;
432 break;
433 }
434
435 /*
436 * Update the btree to show the new hashval for this child.
437 */
438 xfs_da3_fixhashpath(state, &state->path);
439 }
440 if (!addblk)
441 return(0);
442
443 /*
444 * Split the root node.
445 */
446 ASSERT(state->path.active == 0);
447 oldblk = &state->path.blk[0];
448 error = xfs_da3_root_split(state, oldblk, addblk);
449 if (error) {
450 addblk->bp = NULL;
451 return(error); /* GROT: dir is inconsistent */
452 }
453
454 /*
455 * Update pointers to the node which used to be block 0 and
456 * just got bumped because of the addition of a new root node.
457 * There might be three blocks involved if a double split occurred,
458 * and the original block 0 could be at any position in the list.
459 *
460 * Note: the magic numbers and sibling pointers are in the same
461 * physical place for both v2 and v3 headers (by design). Hence it
462 * doesn't matter which version of the xfs_da_intnode structure we use
463 * here as the result will be the same using either structure.
464 */
465 node = oldblk->bp->b_addr;
466 if (node->hdr.info.forw) {
467 if (be32_to_cpu(node->hdr.info.forw) == addblk->blkno) {
468 bp = addblk->bp;
469 } else {
470 ASSERT(state->extravalid);
471 bp = state->extrablk.bp;
472 }
473 node = bp->b_addr;
474 node->hdr.info.back = cpu_to_be32(oldblk->blkno);
475 xfs_trans_log_buf(state->args->trans, bp,
476 XFS_DA_LOGRANGE(node, &node->hdr.info,
477 sizeof(node->hdr.info)));
478 }
479 node = oldblk->bp->b_addr;
480 if (node->hdr.info.back) {
481 if (be32_to_cpu(node->hdr.info.back) == addblk->blkno) {
482 bp = addblk->bp;
483 } else {
484 ASSERT(state->extravalid);
485 bp = state->extrablk.bp;
486 }
487 node = bp->b_addr;
488 node->hdr.info.forw = cpu_to_be32(oldblk->blkno);
489 xfs_trans_log_buf(state->args->trans, bp,
490 XFS_DA_LOGRANGE(node, &node->hdr.info,
491 sizeof(node->hdr.info)));
492 }
493 addblk->bp = NULL;
494 return(0);
495 }
496
497 /*
498 * Split the root. We have to create a new root and point to the two
499 * parts (the split old root) that we just created. Copy block zero to
500 * the EOF, extending the inode in process.
501 */
502 STATIC int /* error */
503 xfs_da3_root_split(
504 struct xfs_da_state *state,
505 struct xfs_da_state_blk *blk1,
506 struct xfs_da_state_blk *blk2)
507 {
508 struct xfs_da_intnode *node;
509 struct xfs_da_intnode *oldroot;
510 struct xfs_da_node_entry *btree;
511 struct xfs_da3_icnode_hdr nodehdr;
512 struct xfs_da_args *args;
513 struct xfs_buf *bp;
514 struct xfs_inode *dp;
515 struct xfs_trans *tp;
516 struct xfs_mount *mp;
517 struct xfs_dir2_leaf *leaf;
518 xfs_dablk_t blkno;
519 int level;
520 int error;
521 int size;
522
523 trace_xfs_da_root_split(state->args);
524
525 /*
526 * Copy the existing (incorrect) block from the root node position
527 * to a free space somewhere.
528 */
529 args = state->args;
530 error = xfs_da_grow_inode(args, &blkno);
531 if (error)
532 return error;
533
534 dp = args->dp;
535 tp = args->trans;
536 mp = state->mp;
537 error = xfs_da_get_buf(tp, dp, blkno, -1, &bp, args->whichfork);
538 if (error)
539 return error;
540 node = bp->b_addr;
541 oldroot = blk1->bp->b_addr;
542 if (oldroot->hdr.info.magic == cpu_to_be16(XFS_DA_NODE_MAGIC) ||
543 oldroot->hdr.info.magic == cpu_to_be16(XFS_DA3_NODE_MAGIC)) {
544 struct xfs_da3_icnode_hdr nodehdr;
545
546 dp->d_ops->node_hdr_from_disk(&nodehdr, oldroot);
547 btree = dp->d_ops->node_tree_p(oldroot);
548 size = (int)((char *)&btree[nodehdr.count] - (char *)oldroot);
549 level = nodehdr.level;
550
551 /*
552 * we are about to copy oldroot to bp, so set up the type
553 * of bp while we know exactly what it will be.
554 */
555 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DA_NODE_BUF);
556 } else {
557 struct xfs_dir3_icleaf_hdr leafhdr;
558 struct xfs_dir2_leaf_entry *ents;
559
560 leaf = (xfs_dir2_leaf_t *)oldroot;
561 dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
562 ents = dp->d_ops->leaf_ents_p(leaf);
563
564 ASSERT(leafhdr.magic == XFS_DIR2_LEAFN_MAGIC ||
565 leafhdr.magic == XFS_DIR3_LEAFN_MAGIC);
566 size = (int)((char *)&ents[leafhdr.count] - (char *)leaf);
567 level = 0;
568
569 /*
570 * we are about to copy oldroot to bp, so set up the type
571 * of bp while we know exactly what it will be.
572 */
573 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_LEAFN_BUF);
574 }
575
576 /*
577 * we can copy most of the information in the node from one block to
578 * another, but for CRC enabled headers we have to make sure that the
579 * block specific identifiers are kept intact. We update the buffer
580 * directly for this.
581 */
582 memcpy(node, oldroot, size);
583 if (oldroot->hdr.info.magic == cpu_to_be16(XFS_DA3_NODE_MAGIC) ||
584 oldroot->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC)) {
585 struct xfs_da3_intnode *node3 = (struct xfs_da3_intnode *)node;
586
587 node3->hdr.info.blkno = cpu_to_be64(bp->b_bn);
588 }
589 xfs_trans_log_buf(tp, bp, 0, size - 1);
590
591 bp->b_ops = blk1->bp->b_ops;
592 xfs_trans_buf_copy_type(bp, blk1->bp);
593 blk1->bp = bp;
594 blk1->blkno = blkno;
595
596 /*
597 * Set up the new root node.
598 */
599 error = xfs_da3_node_create(args,
600 (args->whichfork == XFS_DATA_FORK) ? mp->m_dirleafblk : 0,
601 level + 1, &bp, args->whichfork);
602 if (error)
603 return error;
604
605 node = bp->b_addr;
606 dp->d_ops->node_hdr_from_disk(&nodehdr, node);
607 btree = dp->d_ops->node_tree_p(node);
608 btree[0].hashval = cpu_to_be32(blk1->hashval);
609 btree[0].before = cpu_to_be32(blk1->blkno);
610 btree[1].hashval = cpu_to_be32(blk2->hashval);
611 btree[1].before = cpu_to_be32(blk2->blkno);
612 nodehdr.count = 2;
613 dp->d_ops->node_hdr_to_disk(node, &nodehdr);
614
615 #ifdef DEBUG
616 if (oldroot->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
617 oldroot->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC)) {
618 ASSERT(blk1->blkno >= mp->m_dirleafblk &&
619 blk1->blkno < mp->m_dirfreeblk);
620 ASSERT(blk2->blkno >= mp->m_dirleafblk &&
621 blk2->blkno < mp->m_dirfreeblk);
622 }
623 #endif
624
625 /* Header is already logged by xfs_da_node_create */
626 xfs_trans_log_buf(tp, bp,
627 XFS_DA_LOGRANGE(node, btree, sizeof(xfs_da_node_entry_t) * 2));
628
629 return 0;
630 }
631
632 /*
633 * Split the node, rebalance, then add the new entry.
634 */
635 STATIC int /* error */
636 xfs_da3_node_split(
637 struct xfs_da_state *state,
638 struct xfs_da_state_blk *oldblk,
639 struct xfs_da_state_blk *newblk,
640 struct xfs_da_state_blk *addblk,
641 int treelevel,
642 int *result)
643 {
644 struct xfs_da_intnode *node;
645 struct xfs_da3_icnode_hdr nodehdr;
646 xfs_dablk_t blkno;
647 int newcount;
648 int error;
649 int useextra;
650 struct xfs_inode *dp = state->args->dp;
651
652 trace_xfs_da_node_split(state->args);
653
654 node = oldblk->bp->b_addr;
655 dp->d_ops->node_hdr_from_disk(&nodehdr, node);
656
657 /*
658 * With V2 dirs the extra block is data or freespace.
659 */
660 useextra = state->extravalid && state->args->whichfork == XFS_ATTR_FORK;
661 newcount = 1 + useextra;
662 /*
663 * Do we have to split the node?
664 */
665 if (nodehdr.count + newcount > state->node_ents) {
666 /*
667 * Allocate a new node, add to the doubly linked chain of
668 * nodes, then move some of our excess entries into it.
669 */
670 error = xfs_da_grow_inode(state->args, &blkno);
671 if (error)
672 return(error); /* GROT: dir is inconsistent */
673
674 error = xfs_da3_node_create(state->args, blkno, treelevel,
675 &newblk->bp, state->args->whichfork);
676 if (error)
677 return(error); /* GROT: dir is inconsistent */
678 newblk->blkno = blkno;
679 newblk->magic = XFS_DA_NODE_MAGIC;
680 xfs_da3_node_rebalance(state, oldblk, newblk);
681 error = xfs_da3_blk_link(state, oldblk, newblk);
682 if (error)
683 return(error);
684 *result = 1;
685 } else {
686 *result = 0;
687 }
688
689 /*
690 * Insert the new entry(s) into the correct block
691 * (updating last hashval in the process).
692 *
693 * xfs_da3_node_add() inserts BEFORE the given index,
694 * and as a result of using node_lookup_int() we always
695 * point to a valid entry (not after one), but a split
696 * operation always results in a new block whose hashvals
697 * FOLLOW the current block.
698 *
699 * If we had double-split op below us, then add the extra block too.
700 */
701 node = oldblk->bp->b_addr;
702 dp->d_ops->node_hdr_from_disk(&nodehdr, node);
703 if (oldblk->index <= nodehdr.count) {
704 oldblk->index++;
705 xfs_da3_node_add(state, oldblk, addblk);
706 if (useextra) {
707 if (state->extraafter)
708 oldblk->index++;
709 xfs_da3_node_add(state, oldblk, &state->extrablk);
710 state->extravalid = 0;
711 }
712 } else {
713 newblk->index++;
714 xfs_da3_node_add(state, newblk, addblk);
715 if (useextra) {
716 if (state->extraafter)
717 newblk->index++;
718 xfs_da3_node_add(state, newblk, &state->extrablk);
719 state->extravalid = 0;
720 }
721 }
722
723 return(0);
724 }
725
726 /*
727 * Balance the btree elements between two intermediate nodes,
728 * usually one full and one empty.
729 *
730 * NOTE: if blk2 is empty, then it will get the upper half of blk1.
731 */
732 STATIC void
733 xfs_da3_node_rebalance(
734 struct xfs_da_state *state,
735 struct xfs_da_state_blk *blk1,
736 struct xfs_da_state_blk *blk2)
737 {
738 struct xfs_da_intnode *node1;
739 struct xfs_da_intnode *node2;
740 struct xfs_da_intnode *tmpnode;
741 struct xfs_da_node_entry *btree1;
742 struct xfs_da_node_entry *btree2;
743 struct xfs_da_node_entry *btree_s;
744 struct xfs_da_node_entry *btree_d;
745 struct xfs_da3_icnode_hdr nodehdr1;
746 struct xfs_da3_icnode_hdr nodehdr2;
747 struct xfs_trans *tp;
748 int count;
749 int tmp;
750 int swap = 0;
751 struct xfs_inode *dp = state->args->dp;
752
753 trace_xfs_da_node_rebalance(state->args);
754
755 node1 = blk1->bp->b_addr;
756 node2 = blk2->bp->b_addr;
757 dp->d_ops->node_hdr_from_disk(&nodehdr1, node1);
758 dp->d_ops->node_hdr_from_disk(&nodehdr2, node2);
759 btree1 = dp->d_ops->node_tree_p(node1);
760 btree2 = dp->d_ops->node_tree_p(node2);
761
762 /*
763 * Figure out how many entries need to move, and in which direction.
764 * Swap the nodes around if that makes it simpler.
765 */
766 if (nodehdr1.count > 0 && nodehdr2.count > 0 &&
767 ((be32_to_cpu(btree2[0].hashval) < be32_to_cpu(btree1[0].hashval)) ||
768 (be32_to_cpu(btree2[nodehdr2.count - 1].hashval) <
769 be32_to_cpu(btree1[nodehdr1.count - 1].hashval)))) {
770 tmpnode = node1;
771 node1 = node2;
772 node2 = tmpnode;
773 dp->d_ops->node_hdr_from_disk(&nodehdr1, node1);
774 dp->d_ops->node_hdr_from_disk(&nodehdr2, node2);
775 btree1 = dp->d_ops->node_tree_p(node1);
776 btree2 = dp->d_ops->node_tree_p(node2);
777 swap = 1;
778 }
779
780 count = (nodehdr1.count - nodehdr2.count) / 2;
781 if (count == 0)
782 return;
783 tp = state->args->trans;
784 /*
785 * Two cases: high-to-low and low-to-high.
786 */
787 if (count > 0) {
788 /*
789 * Move elements in node2 up to make a hole.
790 */
791 tmp = nodehdr2.count;
792 if (tmp > 0) {
793 tmp *= (uint)sizeof(xfs_da_node_entry_t);
794 btree_s = &btree2[0];
795 btree_d = &btree2[count];
796 memmove(btree_d, btree_s, tmp);
797 }
798
799 /*
800 * Move the req'd B-tree elements from high in node1 to
801 * low in node2.
802 */
803 nodehdr2.count += count;
804 tmp = count * (uint)sizeof(xfs_da_node_entry_t);
805 btree_s = &btree1[nodehdr1.count - count];
806 btree_d = &btree2[0];
807 memcpy(btree_d, btree_s, tmp);
808 nodehdr1.count -= count;
809 } else {
810 /*
811 * Move the req'd B-tree elements from low in node2 to
812 * high in node1.
813 */
814 count = -count;
815 tmp = count * (uint)sizeof(xfs_da_node_entry_t);
816 btree_s = &btree2[0];
817 btree_d = &btree1[nodehdr1.count];
818 memcpy(btree_d, btree_s, tmp);
819 nodehdr1.count += count;
820
821 xfs_trans_log_buf(tp, blk1->bp,
822 XFS_DA_LOGRANGE(node1, btree_d, tmp));
823
824 /*
825 * Move elements in node2 down to fill the hole.
826 */
827 tmp = nodehdr2.count - count;
828 tmp *= (uint)sizeof(xfs_da_node_entry_t);
829 btree_s = &btree2[count];
830 btree_d = &btree2[0];
831 memmove(btree_d, btree_s, tmp);
832 nodehdr2.count -= count;
833 }
834
835 /*
836 * Log header of node 1 and all current bits of node 2.
837 */
838 dp->d_ops->node_hdr_to_disk(node1, &nodehdr1);
839 xfs_trans_log_buf(tp, blk1->bp,
840 XFS_DA_LOGRANGE(node1, &node1->hdr, dp->d_ops->node_hdr_size));
841
842 dp->d_ops->node_hdr_to_disk(node2, &nodehdr2);
843 xfs_trans_log_buf(tp, blk2->bp,
844 XFS_DA_LOGRANGE(node2, &node2->hdr,
845 dp->d_ops->node_hdr_size +
846 (sizeof(btree2[0]) * nodehdr2.count)));
847
848 /*
849 * Record the last hashval from each block for upward propagation.
850 * (note: don't use the swapped node pointers)
851 */
852 if (swap) {
853 node1 = blk1->bp->b_addr;
854 node2 = blk2->bp->b_addr;
855 dp->d_ops->node_hdr_from_disk(&nodehdr1, node1);
856 dp->d_ops->node_hdr_from_disk(&nodehdr2, node2);
857 btree1 = dp->d_ops->node_tree_p(node1);
858 btree2 = dp->d_ops->node_tree_p(node2);
859 }
860 blk1->hashval = be32_to_cpu(btree1[nodehdr1.count - 1].hashval);
861 blk2->hashval = be32_to_cpu(btree2[nodehdr2.count - 1].hashval);
862
863 /*
864 * Adjust the expected index for insertion.
865 */
866 if (blk1->index >= nodehdr1.count) {
867 blk2->index = blk1->index - nodehdr1.count;
868 blk1->index = nodehdr1.count + 1; /* make it invalid */
869 }
870 }
871
872 /*
873 * Add a new entry to an intermediate node.
874 */
875 STATIC void
876 xfs_da3_node_add(
877 struct xfs_da_state *state,
878 struct xfs_da_state_blk *oldblk,
879 struct xfs_da_state_blk *newblk)
880 {
881 struct xfs_da_intnode *node;
882 struct xfs_da3_icnode_hdr nodehdr;
883 struct xfs_da_node_entry *btree;
884 int tmp;
885 struct xfs_inode *dp = state->args->dp;
886
887 trace_xfs_da_node_add(state->args);
888
889 node = oldblk->bp->b_addr;
890 dp->d_ops->node_hdr_from_disk(&nodehdr, node);
891 btree = dp->d_ops->node_tree_p(node);
892
893 ASSERT(oldblk->index >= 0 && oldblk->index <= nodehdr.count);
894 ASSERT(newblk->blkno != 0);
895 if (state->args->whichfork == XFS_DATA_FORK)
896 ASSERT(newblk->blkno >= state->mp->m_dirleafblk &&
897 newblk->blkno < state->mp->m_dirfreeblk);
898
899 /*
900 * We may need to make some room before we insert the new node.
901 */
902 tmp = 0;
903 if (oldblk->index < nodehdr.count) {
904 tmp = (nodehdr.count - oldblk->index) * (uint)sizeof(*btree);
905 memmove(&btree[oldblk->index + 1], &btree[oldblk->index], tmp);
906 }
907 btree[oldblk->index].hashval = cpu_to_be32(newblk->hashval);
908 btree[oldblk->index].before = cpu_to_be32(newblk->blkno);
909 xfs_trans_log_buf(state->args->trans, oldblk->bp,
910 XFS_DA_LOGRANGE(node, &btree[oldblk->index],
911 tmp + sizeof(*btree)));
912
913 nodehdr.count += 1;
914 dp->d_ops->node_hdr_to_disk(node, &nodehdr);
915 xfs_trans_log_buf(state->args->trans, oldblk->bp,
916 XFS_DA_LOGRANGE(node, &node->hdr, dp->d_ops->node_hdr_size));
917
918 /*
919 * Copy the last hash value from the oldblk to propagate upwards.
920 */
921 oldblk->hashval = be32_to_cpu(btree[nodehdr.count - 1].hashval);
922 }
923
924 /*========================================================================
925 * Routines used for shrinking the Btree.
926 *========================================================================*/
927
928 /*
929 * Deallocate an empty leaf node, remove it from its parent,
930 * possibly deallocating that block, etc...
931 */
932 int
933 xfs_da3_join(
934 struct xfs_da_state *state)
935 {
936 struct xfs_da_state_blk *drop_blk;
937 struct xfs_da_state_blk *save_blk;
938 int action = 0;
939 int error;
940
941 trace_xfs_da_join(state->args);
942
943 drop_blk = &state->path.blk[ state->path.active-1 ];
944 save_blk = &state->altpath.blk[ state->path.active-1 ];
945 ASSERT(state->path.blk[0].magic == XFS_DA_NODE_MAGIC);
946 ASSERT(drop_blk->magic == XFS_ATTR_LEAF_MAGIC ||
947 drop_blk->magic == XFS_DIR2_LEAFN_MAGIC);
948
949 /*
950 * Walk back up the tree joining/deallocating as necessary.
951 * When we stop dropping blocks, break out.
952 */
953 for ( ; state->path.active >= 2; drop_blk--, save_blk--,
954 state->path.active--) {
955 /*
956 * See if we can combine the block with a neighbor.
957 * (action == 0) => no options, just leave
958 * (action == 1) => coalesce, then unlink
959 * (action == 2) => block empty, unlink it
960 */
961 switch (drop_blk->magic) {
962 case XFS_ATTR_LEAF_MAGIC:
963 error = xfs_attr3_leaf_toosmall(state, &action);
964 if (error)
965 return(error);
966 if (action == 0)
967 return(0);
968 xfs_attr3_leaf_unbalance(state, drop_blk, save_blk);
969 break;
970 case XFS_DIR2_LEAFN_MAGIC:
971 error = xfs_dir2_leafn_toosmall(state, &action);
972 if (error)
973 return error;
974 if (action == 0)
975 return 0;
976 xfs_dir2_leafn_unbalance(state, drop_blk, save_blk);
977 break;
978 case XFS_DA_NODE_MAGIC:
979 /*
980 * Remove the offending node, fixup hashvals,
981 * check for a toosmall neighbor.
982 */
983 xfs_da3_node_remove(state, drop_blk);
984 xfs_da3_fixhashpath(state, &state->path);
985 error = xfs_da3_node_toosmall(state, &action);
986 if (error)
987 return(error);
988 if (action == 0)
989 return 0;
990 xfs_da3_node_unbalance(state, drop_blk, save_blk);
991 break;
992 }
993 xfs_da3_fixhashpath(state, &state->altpath);
994 error = xfs_da3_blk_unlink(state, drop_blk, save_blk);
995 xfs_da_state_kill_altpath(state);
996 if (error)
997 return(error);
998 error = xfs_da_shrink_inode(state->args, drop_blk->blkno,
999 drop_blk->bp);
1000 drop_blk->bp = NULL;
1001 if (error)
1002 return(error);
1003 }
1004 /*
1005 * We joined all the way to the top. If it turns out that
1006 * we only have one entry in the root, make the child block
1007 * the new root.
1008 */
1009 xfs_da3_node_remove(state, drop_blk);
1010 xfs_da3_fixhashpath(state, &state->path);
1011 error = xfs_da3_root_join(state, &state->path.blk[0]);
1012 return(error);
1013 }
1014
1015 #ifdef DEBUG
1016 static void
1017 xfs_da_blkinfo_onlychild_validate(struct xfs_da_blkinfo *blkinfo, __u16 level)
1018 {
1019 __be16 magic = blkinfo->magic;
1020
1021 if (level == 1) {
1022 ASSERT(magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1023 magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC) ||
1024 magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC) ||
1025 magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC));
1026 } else {
1027 ASSERT(magic == cpu_to_be16(XFS_DA_NODE_MAGIC) ||
1028 magic == cpu_to_be16(XFS_DA3_NODE_MAGIC));
1029 }
1030 ASSERT(!blkinfo->forw);
1031 ASSERT(!blkinfo->back);
1032 }
1033 #else /* !DEBUG */
1034 #define xfs_da_blkinfo_onlychild_validate(blkinfo, level)
1035 #endif /* !DEBUG */
1036
1037 /*
1038 * We have only one entry in the root. Copy the only remaining child of
1039 * the old root to block 0 as the new root node.
1040 */
1041 STATIC int
1042 xfs_da3_root_join(
1043 struct xfs_da_state *state,
1044 struct xfs_da_state_blk *root_blk)
1045 {
1046 struct xfs_da_intnode *oldroot;
1047 struct xfs_da_args *args;
1048 xfs_dablk_t child;
1049 struct xfs_buf *bp;
1050 struct xfs_da3_icnode_hdr oldroothdr;
1051 struct xfs_da_node_entry *btree;
1052 int error;
1053 struct xfs_inode *dp = state->args->dp;
1054
1055 trace_xfs_da_root_join(state->args);
1056
1057 ASSERT(root_blk->magic == XFS_DA_NODE_MAGIC);
1058
1059 args = state->args;
1060 oldroot = root_blk->bp->b_addr;
1061 dp->d_ops->node_hdr_from_disk(&oldroothdr, oldroot);
1062 ASSERT(oldroothdr.forw == 0);
1063 ASSERT(oldroothdr.back == 0);
1064
1065 /*
1066 * If the root has more than one child, then don't do anything.
1067 */
1068 if (oldroothdr.count > 1)
1069 return 0;
1070
1071 /*
1072 * Read in the (only) child block, then copy those bytes into
1073 * the root block's buffer and free the original child block.
1074 */
1075 btree = dp->d_ops->node_tree_p(oldroot);
1076 child = be32_to_cpu(btree[0].before);
1077 ASSERT(child != 0);
1078 error = xfs_da3_node_read(args->trans, dp, child, -1, &bp,
1079 args->whichfork);
1080 if (error)
1081 return error;
1082 xfs_da_blkinfo_onlychild_validate(bp->b_addr, oldroothdr.level);
1083
1084 /*
1085 * This could be copying a leaf back into the root block in the case of
1086 * there only being a single leaf block left in the tree. Hence we have
1087 * to update the b_ops pointer as well to match the buffer type change
1088 * that could occur. For dir3 blocks we also need to update the block
1089 * number in the buffer header.
1090 */
1091 memcpy(root_blk->bp->b_addr, bp->b_addr, state->blocksize);
1092 root_blk->bp->b_ops = bp->b_ops;
1093 xfs_trans_buf_copy_type(root_blk->bp, bp);
1094 if (oldroothdr.magic == XFS_DA3_NODE_MAGIC) {
1095 struct xfs_da3_blkinfo *da3 = root_blk->bp->b_addr;
1096 da3->blkno = cpu_to_be64(root_blk->bp->b_bn);
1097 }
1098 xfs_trans_log_buf(args->trans, root_blk->bp, 0, state->blocksize - 1);
1099 error = xfs_da_shrink_inode(args, child, bp);
1100 return(error);
1101 }
1102
1103 /*
1104 * Check a node block and its neighbors to see if the block should be
1105 * collapsed into one or the other neighbor. Always keep the block
1106 * with the smaller block number.
1107 * If the current block is over 50% full, don't try to join it, return 0.
1108 * If the block is empty, fill in the state structure and return 2.
1109 * If it can be collapsed, fill in the state structure and return 1.
1110 * If nothing can be done, return 0.
1111 */
1112 STATIC int
1113 xfs_da3_node_toosmall(
1114 struct xfs_da_state *state,
1115 int *action)
1116 {
1117 struct xfs_da_intnode *node;
1118 struct xfs_da_state_blk *blk;
1119 struct xfs_da_blkinfo *info;
1120 xfs_dablk_t blkno;
1121 struct xfs_buf *bp;
1122 struct xfs_da3_icnode_hdr nodehdr;
1123 int count;
1124 int forward;
1125 int error;
1126 int retval;
1127 int i;
1128 struct xfs_inode *dp = state->args->dp;
1129
1130 trace_xfs_da_node_toosmall(state->args);
1131
1132 /*
1133 * Check for the degenerate case of the block being over 50% full.
1134 * If so, it's not worth even looking to see if we might be able
1135 * to coalesce with a sibling.
1136 */
1137 blk = &state->path.blk[ state->path.active-1 ];
1138 info = blk->bp->b_addr;
1139 node = (xfs_da_intnode_t *)info;
1140 dp->d_ops->node_hdr_from_disk(&nodehdr, node);
1141 if (nodehdr.count > (state->node_ents >> 1)) {
1142 *action = 0; /* blk over 50%, don't try to join */
1143 return(0); /* blk over 50%, don't try to join */
1144 }
1145
1146 /*
1147 * Check for the degenerate case of the block being empty.
1148 * If the block is empty, we'll simply delete it, no need to
1149 * coalesce it with a sibling block. We choose (arbitrarily)
1150 * to merge with the forward block unless it is NULL.
1151 */
1152 if (nodehdr.count == 0) {
1153 /*
1154 * Make altpath point to the block we want to keep and
1155 * path point to the block we want to drop (this one).
1156 */
1157 forward = (info->forw != 0);
1158 memcpy(&state->altpath, &state->path, sizeof(state->path));
1159 error = xfs_da3_path_shift(state, &state->altpath, forward,
1160 0, &retval);
1161 if (error)
1162 return(error);
1163 if (retval) {
1164 *action = 0;
1165 } else {
1166 *action = 2;
1167 }
1168 return(0);
1169 }
1170
1171 /*
1172 * Examine each sibling block to see if we can coalesce with
1173 * at least 25% free space to spare. We need to figure out
1174 * whether to merge with the forward or the backward block.
1175 * We prefer coalescing with the lower numbered sibling so as
1176 * to shrink a directory over time.
1177 */
1178 count = state->node_ents;
1179 count -= state->node_ents >> 2;
1180 count -= nodehdr.count;
1181
1182 /* start with smaller blk num */
1183 forward = nodehdr.forw < nodehdr.back;
1184 for (i = 0; i < 2; forward = !forward, i++) {
1185 struct xfs_da3_icnode_hdr thdr;
1186 if (forward)
1187 blkno = nodehdr.forw;
1188 else
1189 blkno = nodehdr.back;
1190 if (blkno == 0)
1191 continue;
1192 error = xfs_da3_node_read(state->args->trans, dp,
1193 blkno, -1, &bp, state->args->whichfork);
1194 if (error)
1195 return(error);
1196
1197 node = bp->b_addr;
1198 dp->d_ops->node_hdr_from_disk(&thdr, node);
1199 xfs_trans_brelse(state->args->trans, bp);
1200
1201 if (count - thdr.count >= 0)
1202 break; /* fits with at least 25% to spare */
1203 }
1204 if (i >= 2) {
1205 *action = 0;
1206 return 0;
1207 }
1208
1209 /*
1210 * Make altpath point to the block we want to keep (the lower
1211 * numbered block) and path point to the block we want to drop.
1212 */
1213 memcpy(&state->altpath, &state->path, sizeof(state->path));
1214 if (blkno < blk->blkno) {
1215 error = xfs_da3_path_shift(state, &state->altpath, forward,
1216 0, &retval);
1217 } else {
1218 error = xfs_da3_path_shift(state, &state->path, forward,
1219 0, &retval);
1220 }
1221 if (error)
1222 return error;
1223 if (retval) {
1224 *action = 0;
1225 return 0;
1226 }
1227 *action = 1;
1228 return 0;
1229 }
1230
1231 /*
1232 * Pick up the last hashvalue from an intermediate node.
1233 */
1234 STATIC uint
1235 xfs_da3_node_lasthash(
1236 struct xfs_inode *dp,
1237 struct xfs_buf *bp,
1238 int *count)
1239 {
1240 struct xfs_da_intnode *node;
1241 struct xfs_da_node_entry *btree;
1242 struct xfs_da3_icnode_hdr nodehdr;
1243
1244 node = bp->b_addr;
1245 dp->d_ops->node_hdr_from_disk(&nodehdr, node);
1246 if (count)
1247 *count = nodehdr.count;
1248 if (!nodehdr.count)
1249 return 0;
1250 btree = dp->d_ops->node_tree_p(node);
1251 return be32_to_cpu(btree[nodehdr.count - 1].hashval);
1252 }
1253
1254 /*
1255 * Walk back up the tree adjusting hash values as necessary,
1256 * when we stop making changes, return.
1257 */
1258 void
1259 xfs_da3_fixhashpath(
1260 struct xfs_da_state *state,
1261 struct xfs_da_state_path *path)
1262 {
1263 struct xfs_da_state_blk *blk;
1264 struct xfs_da_intnode *node;
1265 struct xfs_da_node_entry *btree;
1266 xfs_dahash_t lasthash=0;
1267 int level;
1268 int count;
1269 struct xfs_inode *dp = state->args->dp;
1270
1271 trace_xfs_da_fixhashpath(state->args);
1272
1273 level = path->active-1;
1274 blk = &path->blk[ level ];
1275 switch (blk->magic) {
1276 case XFS_ATTR_LEAF_MAGIC:
1277 lasthash = xfs_attr_leaf_lasthash(blk->bp, &count);
1278 if (count == 0)
1279 return;
1280 break;
1281 case XFS_DIR2_LEAFN_MAGIC:
1282 lasthash = xfs_dir2_leafn_lasthash(dp, blk->bp, &count);
1283 if (count == 0)
1284 return;
1285 break;
1286 case XFS_DA_NODE_MAGIC:
1287 lasthash = xfs_da3_node_lasthash(dp, blk->bp, &count);
1288 if (count == 0)
1289 return;
1290 break;
1291 }
1292 for (blk--, level--; level >= 0; blk--, level--) {
1293 struct xfs_da3_icnode_hdr nodehdr;
1294
1295 node = blk->bp->b_addr;
1296 dp->d_ops->node_hdr_from_disk(&nodehdr, node);
1297 btree = dp->d_ops->node_tree_p(node);
1298 if (be32_to_cpu(btree->hashval) == lasthash)
1299 break;
1300 blk->hashval = lasthash;
1301 btree[blk->index].hashval = cpu_to_be32(lasthash);
1302 xfs_trans_log_buf(state->args->trans, blk->bp,
1303 XFS_DA_LOGRANGE(node, &btree[blk->index],
1304 sizeof(*btree)));
1305
1306 lasthash = be32_to_cpu(btree[nodehdr.count - 1].hashval);
1307 }
1308 }
1309
1310 /*
1311 * Remove an entry from an intermediate node.
1312 */
1313 STATIC void
1314 xfs_da3_node_remove(
1315 struct xfs_da_state *state,
1316 struct xfs_da_state_blk *drop_blk)
1317 {
1318 struct xfs_da_intnode *node;
1319 struct xfs_da3_icnode_hdr nodehdr;
1320 struct xfs_da_node_entry *btree;
1321 int index;
1322 int tmp;
1323 struct xfs_inode *dp = state->args->dp;
1324
1325 trace_xfs_da_node_remove(state->args);
1326
1327 node = drop_blk->bp->b_addr;
1328 dp->d_ops->node_hdr_from_disk(&nodehdr, node);
1329 ASSERT(drop_blk->index < nodehdr.count);
1330 ASSERT(drop_blk->index >= 0);
1331
1332 /*
1333 * Copy over the offending entry, or just zero it out.
1334 */
1335 index = drop_blk->index;
1336 btree = dp->d_ops->node_tree_p(node);
1337 if (index < nodehdr.count - 1) {
1338 tmp = nodehdr.count - index - 1;
1339 tmp *= (uint)sizeof(xfs_da_node_entry_t);
1340 memmove(&btree[index], &btree[index + 1], tmp);
1341 xfs_trans_log_buf(state->args->trans, drop_blk->bp,
1342 XFS_DA_LOGRANGE(node, &btree[index], tmp));
1343 index = nodehdr.count - 1;
1344 }
1345 memset(&btree[index], 0, sizeof(xfs_da_node_entry_t));
1346 xfs_trans_log_buf(state->args->trans, drop_blk->bp,
1347 XFS_DA_LOGRANGE(node, &btree[index], sizeof(btree[index])));
1348 nodehdr.count -= 1;
1349 dp->d_ops->node_hdr_to_disk(node, &nodehdr);
1350 xfs_trans_log_buf(state->args->trans, drop_blk->bp,
1351 XFS_DA_LOGRANGE(node, &node->hdr, dp->d_ops->node_hdr_size));
1352
1353 /*
1354 * Copy the last hash value from the block to propagate upwards.
1355 */
1356 drop_blk->hashval = be32_to_cpu(btree[index - 1].hashval);
1357 }
1358
1359 /*
1360 * Unbalance the elements between two intermediate nodes,
1361 * move all Btree elements from one node into another.
1362 */
1363 STATIC void
1364 xfs_da3_node_unbalance(
1365 struct xfs_da_state *state,
1366 struct xfs_da_state_blk *drop_blk,
1367 struct xfs_da_state_blk *save_blk)
1368 {
1369 struct xfs_da_intnode *drop_node;
1370 struct xfs_da_intnode *save_node;
1371 struct xfs_da_node_entry *drop_btree;
1372 struct xfs_da_node_entry *save_btree;
1373 struct xfs_da3_icnode_hdr drop_hdr;
1374 struct xfs_da3_icnode_hdr save_hdr;
1375 struct xfs_trans *tp;
1376 int sindex;
1377 int tmp;
1378 struct xfs_inode *dp = state->args->dp;
1379
1380 trace_xfs_da_node_unbalance(state->args);
1381
1382 drop_node = drop_blk->bp->b_addr;
1383 save_node = save_blk->bp->b_addr;
1384 dp->d_ops->node_hdr_from_disk(&drop_hdr, drop_node);
1385 dp->d_ops->node_hdr_from_disk(&save_hdr, save_node);
1386 drop_btree = dp->d_ops->node_tree_p(drop_node);
1387 save_btree = dp->d_ops->node_tree_p(save_node);
1388 tp = state->args->trans;
1389
1390 /*
1391 * If the dying block has lower hashvals, then move all the
1392 * elements in the remaining block up to make a hole.
1393 */
1394 if ((be32_to_cpu(drop_btree[0].hashval) <
1395 be32_to_cpu(save_btree[0].hashval)) ||
1396 (be32_to_cpu(drop_btree[drop_hdr.count - 1].hashval) <
1397 be32_to_cpu(save_btree[save_hdr.count - 1].hashval))) {
1398 /* XXX: check this - is memmove dst correct? */
1399 tmp = save_hdr.count * sizeof(xfs_da_node_entry_t);
1400 memmove(&save_btree[drop_hdr.count], &save_btree[0], tmp);
1401
1402 sindex = 0;
1403 xfs_trans_log_buf(tp, save_blk->bp,
1404 XFS_DA_LOGRANGE(save_node, &save_btree[0],
1405 (save_hdr.count + drop_hdr.count) *
1406 sizeof(xfs_da_node_entry_t)));
1407 } else {
1408 sindex = save_hdr.count;
1409 xfs_trans_log_buf(tp, save_blk->bp,
1410 XFS_DA_LOGRANGE(save_node, &save_btree[sindex],
1411 drop_hdr.count * sizeof(xfs_da_node_entry_t)));
1412 }
1413
1414 /*
1415 * Move all the B-tree elements from drop_blk to save_blk.
1416 */
1417 tmp = drop_hdr.count * (uint)sizeof(xfs_da_node_entry_t);
1418 memcpy(&save_btree[sindex], &drop_btree[0], tmp);
1419 save_hdr.count += drop_hdr.count;
1420
1421 dp->d_ops->node_hdr_to_disk(save_node, &save_hdr);
1422 xfs_trans_log_buf(tp, save_blk->bp,
1423 XFS_DA_LOGRANGE(save_node, &save_node->hdr,
1424 dp->d_ops->node_hdr_size));
1425
1426 /*
1427 * Save the last hashval in the remaining block for upward propagation.
1428 */
1429 save_blk->hashval = be32_to_cpu(save_btree[save_hdr.count - 1].hashval);
1430 }
1431
1432 /*========================================================================
1433 * Routines used for finding things in the Btree.
1434 *========================================================================*/
1435
1436 /*
1437 * Walk down the Btree looking for a particular filename, filling
1438 * in the state structure as we go.
1439 *
1440 * We will set the state structure to point to each of the elements
1441 * in each of the nodes where either the hashval is or should be.
1442 *
1443 * We support duplicate hashval's so for each entry in the current
1444 * node that could contain the desired hashval, descend. This is a
1445 * pruned depth-first tree search.
1446 */
1447 int /* error */
1448 xfs_da3_node_lookup_int(
1449 struct xfs_da_state *state,
1450 int *result)
1451 {
1452 struct xfs_da_state_blk *blk;
1453 struct xfs_da_blkinfo *curr;
1454 struct xfs_da_intnode *node;
1455 struct xfs_da_node_entry *btree;
1456 struct xfs_da3_icnode_hdr nodehdr;
1457 struct xfs_da_args *args;
1458 xfs_dablk_t blkno;
1459 xfs_dahash_t hashval;
1460 xfs_dahash_t btreehashval;
1461 int probe;
1462 int span;
1463 int max;
1464 int error;
1465 int retval;
1466 struct xfs_inode *dp = state->args->dp;
1467
1468 args = state->args;
1469
1470 /*
1471 * Descend thru the B-tree searching each level for the right
1472 * node to use, until the right hashval is found.
1473 */
1474 blkno = (args->whichfork == XFS_DATA_FORK)? state->mp->m_dirleafblk : 0;
1475 for (blk = &state->path.blk[0], state->path.active = 1;
1476 state->path.active <= XFS_DA_NODE_MAXDEPTH;
1477 blk++, state->path.active++) {
1478 /*
1479 * Read the next node down in the tree.
1480 */
1481 blk->blkno = blkno;
1482 error = xfs_da3_node_read(args->trans, args->dp, blkno,
1483 -1, &blk->bp, args->whichfork);
1484 if (error) {
1485 blk->blkno = 0;
1486 state->path.active--;
1487 return(error);
1488 }
1489 curr = blk->bp->b_addr;
1490 blk->magic = be16_to_cpu(curr->magic);
1491
1492 if (blk->magic == XFS_ATTR_LEAF_MAGIC ||
1493 blk->magic == XFS_ATTR3_LEAF_MAGIC) {
1494 blk->magic = XFS_ATTR_LEAF_MAGIC;
1495 blk->hashval = xfs_attr_leaf_lasthash(blk->bp, NULL);
1496 break;
1497 }
1498
1499 if (blk->magic == XFS_DIR2_LEAFN_MAGIC ||
1500 blk->magic == XFS_DIR3_LEAFN_MAGIC) {
1501 blk->magic = XFS_DIR2_LEAFN_MAGIC;
1502 blk->hashval = xfs_dir2_leafn_lasthash(args->dp,
1503 blk->bp, NULL);
1504 break;
1505 }
1506
1507 blk->magic = XFS_DA_NODE_MAGIC;
1508
1509
1510 /*
1511 * Search an intermediate node for a match.
1512 */
1513 node = blk->bp->b_addr;
1514 dp->d_ops->node_hdr_from_disk(&nodehdr, node);
1515 btree = dp->d_ops->node_tree_p(node);
1516
1517 max = nodehdr.count;
1518 blk->hashval = be32_to_cpu(btree[max - 1].hashval);
1519
1520 /*
1521 * Binary search. (note: small blocks will skip loop)
1522 */
1523 probe = span = max / 2;
1524 hashval = args->hashval;
1525 while (span > 4) {
1526 span /= 2;
1527 btreehashval = be32_to_cpu(btree[probe].hashval);
1528 if (btreehashval < hashval)
1529 probe += span;
1530 else if (btreehashval > hashval)
1531 probe -= span;
1532 else
1533 break;
1534 }
1535 ASSERT((probe >= 0) && (probe < max));
1536 ASSERT((span <= 4) ||
1537 (be32_to_cpu(btree[probe].hashval) == hashval));
1538
1539 /*
1540 * Since we may have duplicate hashval's, find the first
1541 * matching hashval in the node.
1542 */
1543 while (probe > 0 &&
1544 be32_to_cpu(btree[probe].hashval) >= hashval) {
1545 probe--;
1546 }
1547 while (probe < max &&
1548 be32_to_cpu(btree[probe].hashval) < hashval) {
1549 probe++;
1550 }
1551
1552 /*
1553 * Pick the right block to descend on.
1554 */
1555 if (probe == max) {
1556 blk->index = max - 1;
1557 blkno = be32_to_cpu(btree[max - 1].before);
1558 } else {
1559 blk->index = probe;
1560 blkno = be32_to_cpu(btree[probe].before);
1561 }
1562 }
1563
1564 /*
1565 * A leaf block that ends in the hashval that we are interested in
1566 * (final hashval == search hashval) means that the next block may
1567 * contain more entries with the same hashval, shift upward to the
1568 * next leaf and keep searching.
1569 */
1570 for (;;) {
1571 if (blk->magic == XFS_DIR2_LEAFN_MAGIC) {
1572 retval = xfs_dir2_leafn_lookup_int(blk->bp, args,
1573 &blk->index, state);
1574 } else if (blk->magic == XFS_ATTR_LEAF_MAGIC) {
1575 retval = xfs_attr3_leaf_lookup_int(blk->bp, args);
1576 blk->index = args->index;
1577 args->blkno = blk->blkno;
1578 } else {
1579 ASSERT(0);
1580 return XFS_ERROR(EFSCORRUPTED);
1581 }
1582 if (((retval == ENOENT) || (retval == ENOATTR)) &&
1583 (blk->hashval == args->hashval)) {
1584 error = xfs_da3_path_shift(state, &state->path, 1, 1,
1585 &retval);
1586 if (error)
1587 return(error);
1588 if (retval == 0) {
1589 continue;
1590 } else if (blk->magic == XFS_ATTR_LEAF_MAGIC) {
1591 /* path_shift() gives ENOENT */
1592 retval = XFS_ERROR(ENOATTR);
1593 }
1594 }
1595 break;
1596 }
1597 *result = retval;
1598 return(0);
1599 }
1600
1601 /*========================================================================
1602 * Utility routines.
1603 *========================================================================*/
1604
1605 /*
1606 * Compare two intermediate nodes for "order".
1607 */
1608 STATIC int
1609 xfs_da3_node_order(
1610 struct xfs_inode *dp,
1611 struct xfs_buf *node1_bp,
1612 struct xfs_buf *node2_bp)
1613 {
1614 struct xfs_da_intnode *node1;
1615 struct xfs_da_intnode *node2;
1616 struct xfs_da_node_entry *btree1;
1617 struct xfs_da_node_entry *btree2;
1618 struct xfs_da3_icnode_hdr node1hdr;
1619 struct xfs_da3_icnode_hdr node2hdr;
1620
1621 node1 = node1_bp->b_addr;
1622 node2 = node2_bp->b_addr;
1623 dp->d_ops->node_hdr_from_disk(&node1hdr, node1);
1624 dp->d_ops->node_hdr_from_disk(&node2hdr, node2);
1625 btree1 = dp->d_ops->node_tree_p(node1);
1626 btree2 = dp->d_ops->node_tree_p(node2);
1627
1628 if (node1hdr.count > 0 && node2hdr.count > 0 &&
1629 ((be32_to_cpu(btree2[0].hashval) < be32_to_cpu(btree1[0].hashval)) ||
1630 (be32_to_cpu(btree2[node2hdr.count - 1].hashval) <
1631 be32_to_cpu(btree1[node1hdr.count - 1].hashval)))) {
1632 return 1;
1633 }
1634 return 0;
1635 }
1636
1637 /*
1638 * Link a new block into a doubly linked list of blocks (of whatever type).
1639 */
1640 int /* error */
1641 xfs_da3_blk_link(
1642 struct xfs_da_state *state,
1643 struct xfs_da_state_blk *old_blk,
1644 struct xfs_da_state_blk *new_blk)
1645 {
1646 struct xfs_da_blkinfo *old_info;
1647 struct xfs_da_blkinfo *new_info;
1648 struct xfs_da_blkinfo *tmp_info;
1649 struct xfs_da_args *args;
1650 struct xfs_buf *bp;
1651 int before = 0;
1652 int error;
1653 struct xfs_inode *dp = state->args->dp;
1654
1655 /*
1656 * Set up environment.
1657 */
1658 args = state->args;
1659 ASSERT(args != NULL);
1660 old_info = old_blk->bp->b_addr;
1661 new_info = new_blk->bp->b_addr;
1662 ASSERT(old_blk->magic == XFS_DA_NODE_MAGIC ||
1663 old_blk->magic == XFS_DIR2_LEAFN_MAGIC ||
1664 old_blk->magic == XFS_ATTR_LEAF_MAGIC);
1665
1666 switch (old_blk->magic) {
1667 case XFS_ATTR_LEAF_MAGIC:
1668 before = xfs_attr_leaf_order(old_blk->bp, new_blk->bp);
1669 break;
1670 case XFS_DIR2_LEAFN_MAGIC:
1671 before = xfs_dir2_leafn_order(dp, old_blk->bp, new_blk->bp);
1672 break;
1673 case XFS_DA_NODE_MAGIC:
1674 before = xfs_da3_node_order(dp, old_blk->bp, new_blk->bp);
1675 break;
1676 }
1677
1678 /*
1679 * Link blocks in appropriate order.
1680 */
1681 if (before) {
1682 /*
1683 * Link new block in before existing block.
1684 */
1685 trace_xfs_da_link_before(args);
1686 new_info->forw = cpu_to_be32(old_blk->blkno);
1687 new_info->back = old_info->back;
1688 if (old_info->back) {
1689 error = xfs_da3_node_read(args->trans, dp,
1690 be32_to_cpu(old_info->back),
1691 -1, &bp, args->whichfork);
1692 if (error)
1693 return(error);
1694 ASSERT(bp != NULL);
1695 tmp_info = bp->b_addr;
1696 ASSERT(tmp_info->magic == old_info->magic);
1697 ASSERT(be32_to_cpu(tmp_info->forw) == old_blk->blkno);
1698 tmp_info->forw = cpu_to_be32(new_blk->blkno);
1699 xfs_trans_log_buf(args->trans, bp, 0, sizeof(*tmp_info)-1);
1700 }
1701 old_info->back = cpu_to_be32(new_blk->blkno);
1702 } else {
1703 /*
1704 * Link new block in after existing block.
1705 */
1706 trace_xfs_da_link_after(args);
1707 new_info->forw = old_info->forw;
1708 new_info->back = cpu_to_be32(old_blk->blkno);
1709 if (old_info->forw) {
1710 error = xfs_da3_node_read(args->trans, dp,
1711 be32_to_cpu(old_info->forw),
1712 -1, &bp, args->whichfork);
1713 if (error)
1714 return(error);
1715 ASSERT(bp != NULL);
1716 tmp_info = bp->b_addr;
1717 ASSERT(tmp_info->magic == old_info->magic);
1718 ASSERT(be32_to_cpu(tmp_info->back) == old_blk->blkno);
1719 tmp_info->back = cpu_to_be32(new_blk->blkno);
1720 xfs_trans_log_buf(args->trans, bp, 0, sizeof(*tmp_info)-1);
1721 }
1722 old_info->forw = cpu_to_be32(new_blk->blkno);
1723 }
1724
1725 xfs_trans_log_buf(args->trans, old_blk->bp, 0, sizeof(*tmp_info) - 1);
1726 xfs_trans_log_buf(args->trans, new_blk->bp, 0, sizeof(*tmp_info) - 1);
1727 return(0);
1728 }
1729
1730 /*
1731 * Unlink a block from a doubly linked list of blocks.
1732 */
1733 STATIC int /* error */
1734 xfs_da3_blk_unlink(
1735 struct xfs_da_state *state,
1736 struct xfs_da_state_blk *drop_blk,
1737 struct xfs_da_state_blk *save_blk)
1738 {
1739 struct xfs_da_blkinfo *drop_info;
1740 struct xfs_da_blkinfo *save_info;
1741 struct xfs_da_blkinfo *tmp_info;
1742 struct xfs_da_args *args;
1743 struct xfs_buf *bp;
1744 int error;
1745
1746 /*
1747 * Set up environment.
1748 */
1749 args = state->args;
1750 ASSERT(args != NULL);
1751 save_info = save_blk->bp->b_addr;
1752 drop_info = drop_blk->bp->b_addr;
1753 ASSERT(save_blk->magic == XFS_DA_NODE_MAGIC ||
1754 save_blk->magic == XFS_DIR2_LEAFN_MAGIC ||
1755 save_blk->magic == XFS_ATTR_LEAF_MAGIC);
1756 ASSERT(save_blk->magic == drop_blk->magic);
1757 ASSERT((be32_to_cpu(save_info->forw) == drop_blk->blkno) ||
1758 (be32_to_cpu(save_info->back) == drop_blk->blkno));
1759 ASSERT((be32_to_cpu(drop_info->forw) == save_blk->blkno) ||
1760 (be32_to_cpu(drop_info->back) == save_blk->blkno));
1761
1762 /*
1763 * Unlink the leaf block from the doubly linked chain of leaves.
1764 */
1765 if (be32_to_cpu(save_info->back) == drop_blk->blkno) {
1766 trace_xfs_da_unlink_back(args);
1767 save_info->back = drop_info->back;
1768 if (drop_info->back) {
1769 error = xfs_da3_node_read(args->trans, args->dp,
1770 be32_to_cpu(drop_info->back),
1771 -1, &bp, args->whichfork);
1772 if (error)
1773 return(error);
1774 ASSERT(bp != NULL);
1775 tmp_info = bp->b_addr;
1776 ASSERT(tmp_info->magic == save_info->magic);
1777 ASSERT(be32_to_cpu(tmp_info->forw) == drop_blk->blkno);
1778 tmp_info->forw = cpu_to_be32(save_blk->blkno);
1779 xfs_trans_log_buf(args->trans, bp, 0,
1780 sizeof(*tmp_info) - 1);
1781 }
1782 } else {
1783 trace_xfs_da_unlink_forward(args);
1784 save_info->forw = drop_info->forw;
1785 if (drop_info->forw) {
1786 error = xfs_da3_node_read(args->trans, args->dp,
1787 be32_to_cpu(drop_info->forw),
1788 -1, &bp, args->whichfork);
1789 if (error)
1790 return(error);
1791 ASSERT(bp != NULL);
1792 tmp_info = bp->b_addr;
1793 ASSERT(tmp_info->magic == save_info->magic);
1794 ASSERT(be32_to_cpu(tmp_info->back) == drop_blk->blkno);
1795 tmp_info->back = cpu_to_be32(save_blk->blkno);
1796 xfs_trans_log_buf(args->trans, bp, 0,
1797 sizeof(*tmp_info) - 1);
1798 }
1799 }
1800
1801 xfs_trans_log_buf(args->trans, save_blk->bp, 0, sizeof(*save_info) - 1);
1802 return(0);
1803 }
1804
1805 /*
1806 * Move a path "forward" or "!forward" one block at the current level.
1807 *
1808 * This routine will adjust a "path" to point to the next block
1809 * "forward" (higher hashvalues) or "!forward" (lower hashvals) in the
1810 * Btree, including updating pointers to the intermediate nodes between
1811 * the new bottom and the root.
1812 */
1813 int /* error */
1814 xfs_da3_path_shift(
1815 struct xfs_da_state *state,
1816 struct xfs_da_state_path *path,
1817 int forward,
1818 int release,
1819 int *result)
1820 {
1821 struct xfs_da_state_blk *blk;
1822 struct xfs_da_blkinfo *info;
1823 struct xfs_da_intnode *node;
1824 struct xfs_da_args *args;
1825 struct xfs_da_node_entry *btree;
1826 struct xfs_da3_icnode_hdr nodehdr;
1827 xfs_dablk_t blkno = 0;
1828 int level;
1829 int error;
1830 struct xfs_inode *dp = state->args->dp;
1831
1832 trace_xfs_da_path_shift(state->args);
1833
1834 /*
1835 * Roll up the Btree looking for the first block where our
1836 * current index is not at the edge of the block. Note that
1837 * we skip the bottom layer because we want the sibling block.
1838 */
1839 args = state->args;
1840 ASSERT(args != NULL);
1841 ASSERT(path != NULL);
1842 ASSERT((path->active > 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1843 level = (path->active-1) - 1; /* skip bottom layer in path */
1844 for (blk = &path->blk[level]; level >= 0; blk--, level--) {
1845 node = blk->bp->b_addr;
1846 dp->d_ops->node_hdr_from_disk(&nodehdr, node);
1847 btree = dp->d_ops->node_tree_p(node);
1848
1849 if (forward && (blk->index < nodehdr.count - 1)) {
1850 blk->index++;
1851 blkno = be32_to_cpu(btree[blk->index].before);
1852 break;
1853 } else if (!forward && (blk->index > 0)) {
1854 blk->index--;
1855 blkno = be32_to_cpu(btree[blk->index].before);
1856 break;
1857 }
1858 }
1859 if (level < 0) {
1860 *result = XFS_ERROR(ENOENT); /* we're out of our tree */
1861 ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
1862 return(0);
1863 }
1864
1865 /*
1866 * Roll down the edge of the subtree until we reach the
1867 * same depth we were at originally.
1868 */
1869 for (blk++, level++; level < path->active; blk++, level++) {
1870 /*
1871 * Release the old block.
1872 * (if it's dirty, trans won't actually let go)
1873 */
1874 if (release)
1875 xfs_trans_brelse(args->trans, blk->bp);
1876
1877 /*
1878 * Read the next child block.
1879 */
1880 blk->blkno = blkno;
1881 error = xfs_da3_node_read(args->trans, dp, blkno, -1,
1882 &blk->bp, args->whichfork);
1883 if (error)
1884 return(error);
1885 info = blk->bp->b_addr;
1886 ASSERT(info->magic == cpu_to_be16(XFS_DA_NODE_MAGIC) ||
1887 info->magic == cpu_to_be16(XFS_DA3_NODE_MAGIC) ||
1888 info->magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1889 info->magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC) ||
1890 info->magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC) ||
1891 info->magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC));
1892
1893
1894 /*
1895 * Note: we flatten the magic number to a single type so we
1896 * don't have to compare against crc/non-crc types elsewhere.
1897 */
1898 switch (be16_to_cpu(info->magic)) {
1899 case XFS_DA_NODE_MAGIC:
1900 case XFS_DA3_NODE_MAGIC:
1901 blk->magic = XFS_DA_NODE_MAGIC;
1902 node = (xfs_da_intnode_t *)info;
1903 dp->d_ops->node_hdr_from_disk(&nodehdr, node);
1904 btree = dp->d_ops->node_tree_p(node);
1905 blk->hashval = be32_to_cpu(btree[nodehdr.count - 1].hashval);
1906 if (forward)
1907 blk->index = 0;
1908 else
1909 blk->index = nodehdr.count - 1;
1910 blkno = be32_to_cpu(btree[blk->index].before);
1911 break;
1912 case XFS_ATTR_LEAF_MAGIC:
1913 case XFS_ATTR3_LEAF_MAGIC:
1914 blk->magic = XFS_ATTR_LEAF_MAGIC;
1915 ASSERT(level == path->active-1);
1916 blk->index = 0;
1917 blk->hashval = xfs_attr_leaf_lasthash(blk->bp, NULL);
1918 break;
1919 case XFS_DIR2_LEAFN_MAGIC:
1920 case XFS_DIR3_LEAFN_MAGIC:
1921 blk->magic = XFS_DIR2_LEAFN_MAGIC;
1922 ASSERT(level == path->active-1);
1923 blk->index = 0;
1924 blk->hashval = xfs_dir2_leafn_lasthash(args->dp,
1925 blk->bp, NULL);
1926 break;
1927 default:
1928 ASSERT(0);
1929 break;
1930 }
1931 }
1932 *result = 0;
1933 return 0;
1934 }
1935
1936
1937 /*========================================================================
1938 * Utility routines.
1939 *========================================================================*/
1940
1941 /*
1942 * Implement a simple hash on a character string.
1943 * Rotate the hash value by 7 bits, then XOR each character in.
1944 * This is implemented with some source-level loop unrolling.
1945 */
1946 xfs_dahash_t
1947 xfs_da_hashname(const __uint8_t *name, int namelen)
1948 {
1949 xfs_dahash_t hash;
1950
1951 /*
1952 * Do four characters at a time as long as we can.
1953 */
1954 for (hash = 0; namelen >= 4; namelen -= 4, name += 4)
1955 hash = (name[0] << 21) ^ (name[1] << 14) ^ (name[2] << 7) ^
1956 (name[3] << 0) ^ rol32(hash, 7 * 4);
1957
1958 /*
1959 * Now do the rest of the characters.
1960 */
1961 switch (namelen) {
1962 case 3:
1963 return (name[0] << 14) ^ (name[1] << 7) ^ (name[2] << 0) ^
1964 rol32(hash, 7 * 3);
1965 case 2:
1966 return (name[0] << 7) ^ (name[1] << 0) ^ rol32(hash, 7 * 2);
1967 case 1:
1968 return (name[0] << 0) ^ rol32(hash, 7 * 1);
1969 default: /* case 0: */
1970 return hash;
1971 }
1972 }
1973
1974 enum xfs_dacmp
1975 xfs_da_compname(
1976 struct xfs_da_args *args,
1977 const unsigned char *name,
1978 int len)
1979 {
1980 return (args->namelen == len && memcmp(args->name, name, len) == 0) ?
1981 XFS_CMP_EXACT : XFS_CMP_DIFFERENT;
1982 }
1983
1984 static xfs_dahash_t
1985 xfs_default_hashname(
1986 struct xfs_name *name)
1987 {
1988 return xfs_da_hashname(name->name, name->len);
1989 }
1990
1991 const struct xfs_nameops xfs_default_nameops = {
1992 .hashname = xfs_default_hashname,
1993 .compname = xfs_da_compname
1994 };
1995
1996 int
1997 xfs_da_grow_inode_int(
1998 struct xfs_da_args *args,
1999 xfs_fileoff_t *bno,
2000 int count)
2001 {
2002 struct xfs_trans *tp = args->trans;
2003 struct xfs_inode *dp = args->dp;
2004 int w = args->whichfork;
2005 xfs_drfsbno_t nblks = dp->i_d.di_nblocks;
2006 struct xfs_bmbt_irec map, *mapp;
2007 int nmap, error, got, i, mapi;
2008
2009 /*
2010 * Find a spot in the file space to put the new block.
2011 */
2012 error = xfs_bmap_first_unused(tp, dp, count, bno, w);
2013 if (error)
2014 return error;
2015
2016 /*
2017 * Try mapping it in one filesystem block.
2018 */
2019 nmap = 1;
2020 ASSERT(args->firstblock != NULL);
2021 error = xfs_bmapi_write(tp, dp, *bno, count,
2022 xfs_bmapi_aflag(w)|XFS_BMAPI_METADATA|XFS_BMAPI_CONTIG,
2023 args->firstblock, args->total, &map, &nmap,
2024 args->flist);
2025 if (error)
2026 return error;
2027
2028 ASSERT(nmap <= 1);
2029 if (nmap == 1) {
2030 mapp = &map;
2031 mapi = 1;
2032 } else if (nmap == 0 && count > 1) {
2033 xfs_fileoff_t b;
2034 int c;
2035
2036 /*
2037 * If we didn't get it and the block might work if fragmented,
2038 * try without the CONTIG flag. Loop until we get it all.
2039 */
2040 mapp = kmem_alloc(sizeof(*mapp) * count, KM_SLEEP);
2041 for (b = *bno, mapi = 0; b < *bno + count; ) {
2042 nmap = MIN(XFS_BMAP_MAX_NMAP, count);
2043 c = (int)(*bno + count - b);
2044 error = xfs_bmapi_write(tp, dp, b, c,
2045 xfs_bmapi_aflag(w)|XFS_BMAPI_METADATA,
2046 args->firstblock, args->total,
2047 &mapp[mapi], &nmap, args->flist);
2048 if (error)
2049 goto out_free_map;
2050 if (nmap < 1)
2051 break;
2052 mapi += nmap;
2053 b = mapp[mapi - 1].br_startoff +
2054 mapp[mapi - 1].br_blockcount;
2055 }
2056 } else {
2057 mapi = 0;
2058 mapp = NULL;
2059 }
2060
2061 /*
2062 * Count the blocks we got, make sure it matches the total.
2063 */
2064 for (i = 0, got = 0; i < mapi; i++)
2065 got += mapp[i].br_blockcount;
2066 if (got != count || mapp[0].br_startoff != *bno ||
2067 mapp[mapi - 1].br_startoff + mapp[mapi - 1].br_blockcount !=
2068 *bno + count) {
2069 error = XFS_ERROR(ENOSPC);
2070 goto out_free_map;
2071 }
2072
2073 /* account for newly allocated blocks in reserved blocks total */
2074 args->total -= dp->i_d.di_nblocks - nblks;
2075
2076 out_free_map:
2077 if (mapp != &map)
2078 kmem_free(mapp);
2079 return error;
2080 }
2081
2082 /*
2083 * Add a block to the btree ahead of the file.
2084 * Return the new block number to the caller.
2085 */
2086 int
2087 xfs_da_grow_inode(
2088 struct xfs_da_args *args,
2089 xfs_dablk_t *new_blkno)
2090 {
2091 xfs_fileoff_t bno;
2092 int count;
2093 int error;
2094
2095 trace_xfs_da_grow_inode(args);
2096
2097 if (args->whichfork == XFS_DATA_FORK) {
2098 bno = args->dp->i_mount->m_dirleafblk;
2099 count = args->dp->i_mount->m_dirblkfsbs;
2100 } else {
2101 bno = 0;
2102 count = 1;
2103 }
2104
2105 error = xfs_da_grow_inode_int(args, &bno, count);
2106 if (!error)
2107 *new_blkno = (xfs_dablk_t)bno;
2108 return error;
2109 }
2110
2111 /*
2112 * Ick. We need to always be able to remove a btree block, even
2113 * if there's no space reservation because the filesystem is full.
2114 * This is called if xfs_bunmapi on a btree block fails due to ENOSPC.
2115 * It swaps the target block with the last block in the file. The
2116 * last block in the file can always be removed since it can't cause
2117 * a bmap btree split to do that.
2118 */
2119 STATIC int
2120 xfs_da3_swap_lastblock(
2121 struct xfs_da_args *args,
2122 xfs_dablk_t *dead_blknop,
2123 struct xfs_buf **dead_bufp)
2124 {
2125 struct xfs_da_blkinfo *dead_info;
2126 struct xfs_da_blkinfo *sib_info;
2127 struct xfs_da_intnode *par_node;
2128 struct xfs_da_intnode *dead_node;
2129 struct xfs_dir2_leaf *dead_leaf2;
2130 struct xfs_da_node_entry *btree;
2131 struct xfs_da3_icnode_hdr par_hdr;
2132 struct xfs_inode *dp;
2133 struct xfs_trans *tp;
2134 struct xfs_mount *mp;
2135 struct xfs_buf *dead_buf;
2136 struct xfs_buf *last_buf;
2137 struct xfs_buf *sib_buf;
2138 struct xfs_buf *par_buf;
2139 xfs_dahash_t dead_hash;
2140 xfs_fileoff_t lastoff;
2141 xfs_dablk_t dead_blkno;
2142 xfs_dablk_t last_blkno;
2143 xfs_dablk_t sib_blkno;
2144 xfs_dablk_t par_blkno;
2145 int error;
2146 int w;
2147 int entno;
2148 int level;
2149 int dead_level;
2150
2151 trace_xfs_da_swap_lastblock(args);
2152
2153 dead_buf = *dead_bufp;
2154 dead_blkno = *dead_blknop;
2155 tp = args->trans;
2156 dp = args->dp;
2157 w = args->whichfork;
2158 ASSERT(w == XFS_DATA_FORK);
2159 mp = dp->i_mount;
2160 lastoff = mp->m_dirfreeblk;
2161 error = xfs_bmap_last_before(tp, dp, &lastoff, w);
2162 if (error)
2163 return error;
2164 if (unlikely(lastoff == 0)) {
2165 XFS_ERROR_REPORT("xfs_da_swap_lastblock(1)", XFS_ERRLEVEL_LOW,
2166 mp);
2167 return XFS_ERROR(EFSCORRUPTED);
2168 }
2169 /*
2170 * Read the last block in the btree space.
2171 */
2172 last_blkno = (xfs_dablk_t)lastoff - mp->m_dirblkfsbs;
2173 error = xfs_da3_node_read(tp, dp, last_blkno, -1, &last_buf, w);
2174 if (error)
2175 return error;
2176 /*
2177 * Copy the last block into the dead buffer and log it.
2178 */
2179 memcpy(dead_buf->b_addr, last_buf->b_addr, mp->m_dirblksize);
2180 xfs_trans_log_buf(tp, dead_buf, 0, mp->m_dirblksize - 1);
2181 dead_info = dead_buf->b_addr;
2182 /*
2183 * Get values from the moved block.
2184 */
2185 if (dead_info->magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
2186 dead_info->magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC)) {
2187 struct xfs_dir3_icleaf_hdr leafhdr;
2188 struct xfs_dir2_leaf_entry *ents;
2189
2190 dead_leaf2 = (xfs_dir2_leaf_t *)dead_info;
2191 dp->d_ops->leaf_hdr_from_disk(&leafhdr, dead_leaf2);
2192 ents = dp->d_ops->leaf_ents_p(dead_leaf2);
2193 dead_level = 0;
2194 dead_hash = be32_to_cpu(ents[leafhdr.count - 1].hashval);
2195 } else {
2196 struct xfs_da3_icnode_hdr deadhdr;
2197
2198 dead_node = (xfs_da_intnode_t *)dead_info;
2199 dp->d_ops->node_hdr_from_disk(&deadhdr, dead_node);
2200 btree = dp->d_ops->node_tree_p(dead_node);
2201 dead_level = deadhdr.level;
2202 dead_hash = be32_to_cpu(btree[deadhdr.count - 1].hashval);
2203 }
2204 sib_buf = par_buf = NULL;
2205 /*
2206 * If the moved block has a left sibling, fix up the pointers.
2207 */
2208 if ((sib_blkno = be32_to_cpu(dead_info->back))) {
2209 error = xfs_da3_node_read(tp, dp, sib_blkno, -1, &sib_buf, w);
2210 if (error)
2211 goto done;
2212 sib_info = sib_buf->b_addr;
2213 if (unlikely(
2214 be32_to_cpu(sib_info->forw) != last_blkno ||
2215 sib_info->magic != dead_info->magic)) {
2216 XFS_ERROR_REPORT("xfs_da_swap_lastblock(2)",
2217 XFS_ERRLEVEL_LOW, mp);
2218 error = XFS_ERROR(EFSCORRUPTED);
2219 goto done;
2220 }
2221 sib_info->forw = cpu_to_be32(dead_blkno);
2222 xfs_trans_log_buf(tp, sib_buf,
2223 XFS_DA_LOGRANGE(sib_info, &sib_info->forw,
2224 sizeof(sib_info->forw)));
2225 sib_buf = NULL;
2226 }
2227 /*
2228 * If the moved block has a right sibling, fix up the pointers.
2229 */
2230 if ((sib_blkno = be32_to_cpu(dead_info->forw))) {
2231 error = xfs_da3_node_read(tp, dp, sib_blkno, -1, &sib_buf, w);
2232 if (error)
2233 goto done;
2234 sib_info = sib_buf->b_addr;
2235 if (unlikely(
2236 be32_to_cpu(sib_info->back) != last_blkno ||
2237 sib_info->magic != dead_info->magic)) {
2238 XFS_ERROR_REPORT("xfs_da_swap_lastblock(3)",
2239 XFS_ERRLEVEL_LOW, mp);
2240 error = XFS_ERROR(EFSCORRUPTED);
2241 goto done;
2242 }
2243 sib_info->back = cpu_to_be32(dead_blkno);
2244 xfs_trans_log_buf(tp, sib_buf,
2245 XFS_DA_LOGRANGE(sib_info, &sib_info->back,
2246 sizeof(sib_info->back)));
2247 sib_buf = NULL;
2248 }
2249 par_blkno = mp->m_dirleafblk;
2250 level = -1;
2251 /*
2252 * Walk down the tree looking for the parent of the moved block.
2253 */
2254 for (;;) {
2255 error = xfs_da3_node_read(tp, dp, par_blkno, -1, &par_buf, w);
2256 if (error)
2257 goto done;
2258 par_node = par_buf->b_addr;
2259 dp->d_ops->node_hdr_from_disk(&par_hdr, par_node);
2260 if (level >= 0 && level != par_hdr.level + 1) {
2261 XFS_ERROR_REPORT("xfs_da_swap_lastblock(4)",
2262 XFS_ERRLEVEL_LOW, mp);
2263 error = XFS_ERROR(EFSCORRUPTED);
2264 goto done;
2265 }
2266 level = par_hdr.level;
2267 btree = dp->d_ops->node_tree_p(par_node);
2268 for (entno = 0;
2269 entno < par_hdr.count &&
2270 be32_to_cpu(btree[entno].hashval) < dead_hash;
2271 entno++)
2272 continue;
2273 if (entno == par_hdr.count) {
2274 XFS_ERROR_REPORT("xfs_da_swap_lastblock(5)",
2275 XFS_ERRLEVEL_LOW, mp);
2276 error = XFS_ERROR(EFSCORRUPTED);
2277 goto done;
2278 }
2279 par_blkno = be32_to_cpu(btree[entno].before);
2280 if (level == dead_level + 1)
2281 break;
2282 xfs_trans_brelse(tp, par_buf);
2283 par_buf = NULL;
2284 }
2285 /*
2286 * We're in the right parent block.
2287 * Look for the right entry.
2288 */
2289 for (;;) {
2290 for (;
2291 entno < par_hdr.count &&
2292 be32_to_cpu(btree[entno].before) != last_blkno;
2293 entno++)
2294 continue;
2295 if (entno < par_hdr.count)
2296 break;
2297 par_blkno = par_hdr.forw;
2298 xfs_trans_brelse(tp, par_buf);
2299 par_buf = NULL;
2300 if (unlikely(par_blkno == 0)) {
2301 XFS_ERROR_REPORT("xfs_da_swap_lastblock(6)",
2302 XFS_ERRLEVEL_LOW, mp);
2303 error = XFS_ERROR(EFSCORRUPTED);
2304 goto done;
2305 }
2306 error = xfs_da3_node_read(tp, dp, par_blkno, -1, &par_buf, w);
2307 if (error)
2308 goto done;
2309 par_node = par_buf->b_addr;
2310 dp->d_ops->node_hdr_from_disk(&par_hdr, par_node);
2311 if (par_hdr.level != level) {
2312 XFS_ERROR_REPORT("xfs_da_swap_lastblock(7)",
2313 XFS_ERRLEVEL_LOW, mp);
2314 error = XFS_ERROR(EFSCORRUPTED);
2315 goto done;
2316 }
2317 btree = dp->d_ops->node_tree_p(par_node);
2318 entno = 0;
2319 }
2320 /*
2321 * Update the parent entry pointing to the moved block.
2322 */
2323 btree[entno].before = cpu_to_be32(dead_blkno);
2324 xfs_trans_log_buf(tp, par_buf,
2325 XFS_DA_LOGRANGE(par_node, &btree[entno].before,
2326 sizeof(btree[entno].before)));
2327 *dead_blknop = last_blkno;
2328 *dead_bufp = last_buf;
2329 return 0;
2330 done:
2331 if (par_buf)
2332 xfs_trans_brelse(tp, par_buf);
2333 if (sib_buf)
2334 xfs_trans_brelse(tp, sib_buf);
2335 xfs_trans_brelse(tp, last_buf);
2336 return error;
2337 }
2338
2339 /*
2340 * Remove a btree block from a directory or attribute.
2341 */
2342 int
2343 xfs_da_shrink_inode(
2344 xfs_da_args_t *args,
2345 xfs_dablk_t dead_blkno,
2346 struct xfs_buf *dead_buf)
2347 {
2348 xfs_inode_t *dp;
2349 int done, error, w, count;
2350 xfs_trans_t *tp;
2351 xfs_mount_t *mp;
2352
2353 trace_xfs_da_shrink_inode(args);
2354
2355 dp = args->dp;
2356 w = args->whichfork;
2357 tp = args->trans;
2358 mp = dp->i_mount;
2359 if (w == XFS_DATA_FORK)
2360 count = mp->m_dirblkfsbs;
2361 else
2362 count = 1;
2363 for (;;) {
2364 /*
2365 * Remove extents. If we get ENOSPC for a dir we have to move
2366 * the last block to the place we want to kill.
2367 */
2368 error = xfs_bunmapi(tp, dp, dead_blkno, count,
2369 xfs_bmapi_aflag(w)|XFS_BMAPI_METADATA,
2370 0, args->firstblock, args->flist, &done);
2371 if (error == ENOSPC) {
2372 if (w != XFS_DATA_FORK)
2373 break;
2374 error = xfs_da3_swap_lastblock(args, &dead_blkno,
2375 &dead_buf);
2376 if (error)
2377 break;
2378 } else {
2379 break;
2380 }
2381 }
2382 xfs_trans_binval(tp, dead_buf);
2383 return error;
2384 }
2385
2386 /*
2387 * See if the mapping(s) for this btree block are valid, i.e.
2388 * don't contain holes, are logically contiguous, and cover the whole range.
2389 */
2390 STATIC int
2391 xfs_da_map_covers_blocks(
2392 int nmap,
2393 xfs_bmbt_irec_t *mapp,
2394 xfs_dablk_t bno,
2395 int count)
2396 {
2397 int i;
2398 xfs_fileoff_t off;
2399
2400 for (i = 0, off = bno; i < nmap; i++) {
2401 if (mapp[i].br_startblock == HOLESTARTBLOCK ||
2402 mapp[i].br_startblock == DELAYSTARTBLOCK) {
2403 return 0;
2404 }
2405 if (off != mapp[i].br_startoff) {
2406 return 0;
2407 }
2408 off += mapp[i].br_blockcount;
2409 }
2410 return off == bno + count;
2411 }
2412
2413 /*
2414 * Convert a struct xfs_bmbt_irec to a struct xfs_buf_map.
2415 *
2416 * For the single map case, it is assumed that the caller has provided a pointer
2417 * to a valid xfs_buf_map. For the multiple map case, this function will
2418 * allocate the xfs_buf_map to hold all the maps and replace the caller's single
2419 * map pointer with the allocated map.
2420 */
2421 static int
2422 xfs_buf_map_from_irec(
2423 struct xfs_mount *mp,
2424 struct xfs_buf_map **mapp,
2425 int *nmaps,
2426 struct xfs_bmbt_irec *irecs,
2427 int nirecs)
2428 {
2429 struct xfs_buf_map *map;
2430 int i;
2431
2432 ASSERT(*nmaps == 1);
2433 ASSERT(nirecs >= 1);
2434
2435 if (nirecs > 1) {
2436 map = kmem_zalloc(nirecs * sizeof(struct xfs_buf_map),
2437 KM_SLEEP | KM_NOFS);
2438 if (!map)
2439 return ENOMEM;
2440 *mapp = map;
2441 }
2442
2443 *nmaps = nirecs;
2444 map = *mapp;
2445 for (i = 0; i < *nmaps; i++) {
2446 ASSERT(irecs[i].br_startblock != DELAYSTARTBLOCK &&
2447 irecs[i].br_startblock != HOLESTARTBLOCK);
2448 map[i].bm_bn = XFS_FSB_TO_DADDR(mp, irecs[i].br_startblock);
2449 map[i].bm_len = XFS_FSB_TO_BB(mp, irecs[i].br_blockcount);
2450 }
2451 return 0;
2452 }
2453
2454 /*
2455 * Map the block we are given ready for reading. There are three possible return
2456 * values:
2457 * -1 - will be returned if we land in a hole and mappedbno == -2 so the
2458 * caller knows not to execute a subsequent read.
2459 * 0 - if we mapped the block successfully
2460 * >0 - positive error number if there was an error.
2461 */
2462 static int
2463 xfs_dabuf_map(
2464 struct xfs_trans *trans,
2465 struct xfs_inode *dp,
2466 xfs_dablk_t bno,
2467 xfs_daddr_t mappedbno,
2468 int whichfork,
2469 struct xfs_buf_map **map,
2470 int *nmaps)
2471 {
2472 struct xfs_mount *mp = dp->i_mount;
2473 int nfsb;
2474 int error = 0;
2475 struct xfs_bmbt_irec irec;
2476 struct xfs_bmbt_irec *irecs = &irec;
2477 int nirecs;
2478
2479 ASSERT(map && *map);
2480 ASSERT(*nmaps == 1);
2481
2482 nfsb = (whichfork == XFS_DATA_FORK) ? mp->m_dirblkfsbs : 1;
2483
2484 /*
2485 * Caller doesn't have a mapping. -2 means don't complain
2486 * if we land in a hole.
2487 */
2488 if (mappedbno == -1 || mappedbno == -2) {
2489 /*
2490 * Optimize the one-block case.
2491 */
2492 if (nfsb != 1)
2493 irecs = kmem_zalloc(sizeof(irec) * nfsb,
2494 KM_SLEEP | KM_NOFS);
2495
2496 nirecs = nfsb;
2497 error = xfs_bmapi_read(dp, (xfs_fileoff_t)bno, nfsb, irecs,
2498 &nirecs, xfs_bmapi_aflag(whichfork));
2499 if (error)
2500 goto out;
2501 } else {
2502 irecs->br_startblock = XFS_DADDR_TO_FSB(mp, mappedbno);
2503 irecs->br_startoff = (xfs_fileoff_t)bno;
2504 irecs->br_blockcount = nfsb;
2505 irecs->br_state = 0;
2506 nirecs = 1;
2507 }
2508
2509 if (!xfs_da_map_covers_blocks(nirecs, irecs, bno, nfsb)) {
2510 error = mappedbno == -2 ? -1 : XFS_ERROR(EFSCORRUPTED);
2511 if (unlikely(error == EFSCORRUPTED)) {
2512 if (xfs_error_level >= XFS_ERRLEVEL_LOW) {
2513 int i;
2514 xfs_alert(mp, "%s: bno %lld dir: inode %lld",
2515 __func__, (long long)bno,
2516 (long long)dp->i_ino);
2517 for (i = 0; i < *nmaps; i++) {
2518 xfs_alert(mp,
2519 "[%02d] br_startoff %lld br_startblock %lld br_blockcount %lld br_state %d",
2520 i,
2521 (long long)irecs[i].br_startoff,
2522 (long long)irecs[i].br_startblock,
2523 (long long)irecs[i].br_blockcount,
2524 irecs[i].br_state);
2525 }
2526 }
2527 XFS_ERROR_REPORT("xfs_da_do_buf(1)",
2528 XFS_ERRLEVEL_LOW, mp);
2529 }
2530 goto out;
2531 }
2532 error = xfs_buf_map_from_irec(mp, map, nmaps, irecs, nirecs);
2533 out:
2534 if (irecs != &irec)
2535 kmem_free(irecs);
2536 return error;
2537 }
2538
2539 /*
2540 * Get a buffer for the dir/attr block.
2541 */
2542 int
2543 xfs_da_get_buf(
2544 struct xfs_trans *trans,
2545 struct xfs_inode *dp,
2546 xfs_dablk_t bno,
2547 xfs_daddr_t mappedbno,
2548 struct xfs_buf **bpp,
2549 int whichfork)
2550 {
2551 struct xfs_buf *bp;
2552 struct xfs_buf_map map;
2553 struct xfs_buf_map *mapp;
2554 int nmap;
2555 int error;
2556
2557 *bpp = NULL;
2558 mapp = &map;
2559 nmap = 1;
2560 error = xfs_dabuf_map(trans, dp, bno, mappedbno, whichfork,
2561 &mapp, &nmap);
2562 if (error) {
2563 /* mapping a hole is not an error, but we don't continue */
2564 if (error == -1)
2565 error = 0;
2566 goto out_free;
2567 }
2568
2569 bp = xfs_trans_get_buf_map(trans, dp->i_mount->m_ddev_targp,
2570 mapp, nmap, 0);
2571 error = bp ? bp->b_error : XFS_ERROR(EIO);
2572 if (error) {
2573 xfs_trans_brelse(trans, bp);
2574 goto out_free;
2575 }
2576
2577 *bpp = bp;
2578
2579 out_free:
2580 if (mapp != &map)
2581 kmem_free(mapp);
2582
2583 return error;
2584 }
2585
2586 /*
2587 * Get a buffer for the dir/attr block, fill in the contents.
2588 */
2589 int
2590 xfs_da_read_buf(
2591 struct xfs_trans *trans,
2592 struct xfs_inode *dp,
2593 xfs_dablk_t bno,
2594 xfs_daddr_t mappedbno,
2595 struct xfs_buf **bpp,
2596 int whichfork,
2597 const struct xfs_buf_ops *ops)
2598 {
2599 struct xfs_buf *bp;
2600 struct xfs_buf_map map;
2601 struct xfs_buf_map *mapp;
2602 int nmap;
2603 int error;
2604
2605 *bpp = NULL;
2606 mapp = &map;
2607 nmap = 1;
2608 error = xfs_dabuf_map(trans, dp, bno, mappedbno, whichfork,
2609 &mapp, &nmap);
2610 if (error) {
2611 /* mapping a hole is not an error, but we don't continue */
2612 if (error == -1)
2613 error = 0;
2614 goto out_free;
2615 }
2616
2617 error = xfs_trans_read_buf_map(dp->i_mount, trans,
2618 dp->i_mount->m_ddev_targp,
2619 mapp, nmap, 0, &bp, ops);
2620 if (error)
2621 goto out_free;
2622
2623 if (whichfork == XFS_ATTR_FORK)
2624 xfs_buf_set_ref(bp, XFS_ATTR_BTREE_REF);
2625 else
2626 xfs_buf_set_ref(bp, XFS_DIR_BTREE_REF);
2627
2628 /*
2629 * This verification code will be moved to a CRC verification callback
2630 * function so just leave it here unchanged until then.
2631 */
2632 {
2633 xfs_dir2_data_hdr_t *hdr = bp->b_addr;
2634 xfs_dir2_free_t *free = bp->b_addr;
2635 xfs_da_blkinfo_t *info = bp->b_addr;
2636 uint magic, magic1;
2637 struct xfs_mount *mp = dp->i_mount;
2638
2639 magic = be16_to_cpu(info->magic);
2640 magic1 = be32_to_cpu(hdr->magic);
2641 if (unlikely(
2642 XFS_TEST_ERROR((magic != XFS_DA_NODE_MAGIC) &&
2643 (magic != XFS_DA3_NODE_MAGIC) &&
2644 (magic != XFS_ATTR_LEAF_MAGIC) &&
2645 (magic != XFS_ATTR3_LEAF_MAGIC) &&
2646 (magic != XFS_DIR2_LEAF1_MAGIC) &&
2647 (magic != XFS_DIR3_LEAF1_MAGIC) &&
2648 (magic != XFS_DIR2_LEAFN_MAGIC) &&
2649 (magic != XFS_DIR3_LEAFN_MAGIC) &&
2650 (magic1 != XFS_DIR2_BLOCK_MAGIC) &&
2651 (magic1 != XFS_DIR3_BLOCK_MAGIC) &&
2652 (magic1 != XFS_DIR2_DATA_MAGIC) &&
2653 (magic1 != XFS_DIR3_DATA_MAGIC) &&
2654 (free->hdr.magic !=
2655 cpu_to_be32(XFS_DIR2_FREE_MAGIC)) &&
2656 (free->hdr.magic !=
2657 cpu_to_be32(XFS_DIR3_FREE_MAGIC)),
2658 mp, XFS_ERRTAG_DA_READ_BUF,
2659 XFS_RANDOM_DA_READ_BUF))) {
2660 trace_xfs_da_btree_corrupt(bp, _RET_IP_);
2661 XFS_CORRUPTION_ERROR("xfs_da_do_buf(2)",
2662 XFS_ERRLEVEL_LOW, mp, info);
2663 error = XFS_ERROR(EFSCORRUPTED);
2664 xfs_trans_brelse(trans, bp);
2665 goto out_free;
2666 }
2667 }
2668 *bpp = bp;
2669 out_free:
2670 if (mapp != &map)
2671 kmem_free(mapp);
2672
2673 return error;
2674 }
2675
2676 /*
2677 * Readahead the dir/attr block.
2678 */
2679 xfs_daddr_t
2680 xfs_da_reada_buf(
2681 struct xfs_trans *trans,
2682 struct xfs_inode *dp,
2683 xfs_dablk_t bno,
2684 xfs_daddr_t mappedbno,
2685 int whichfork,
2686 const struct xfs_buf_ops *ops)
2687 {
2688 struct xfs_buf_map map;
2689 struct xfs_buf_map *mapp;
2690 int nmap;
2691 int error;
2692
2693 mapp = &map;
2694 nmap = 1;
2695 error = xfs_dabuf_map(trans, dp, bno, mappedbno, whichfork,
2696 &mapp, &nmap);
2697 if (error) {
2698 /* mapping a hole is not an error, but we don't continue */
2699 if (error == -1)
2700 error = 0;
2701 goto out_free;
2702 }
2703
2704 mappedbno = mapp[0].bm_bn;
2705 xfs_buf_readahead_map(dp->i_mount->m_ddev_targp, mapp, nmap, ops);
2706
2707 out_free:
2708 if (mapp != &map)
2709 kmem_free(mapp);
2710
2711 if (error)
2712 return -1;
2713 return mappedbno;
2714 }
Linux with added FPC-III support