[NETFILTER]: nf_conntrack: add helper function for expectation initialization
[hh.org.git] / fs / xfs / xfs_da_btree.c
bloba68bc1f1a313c8862106adedf30ef84d65b92cd8
1 /*
2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 #include "xfs.h"
19 #include "xfs_fs.h"
20 #include "xfs_types.h"
21 #include "xfs_bit.h"
22 #include "xfs_log.h"
23 #include "xfs_inum.h"
24 #include "xfs_trans.h"
25 #include "xfs_sb.h"
26 #include "xfs_ag.h"
27 #include "xfs_dir2.h"
28 #include "xfs_dmapi.h"
29 #include "xfs_mount.h"
30 #include "xfs_da_btree.h"
31 #include "xfs_bmap_btree.h"
32 #include "xfs_alloc_btree.h"
33 #include "xfs_ialloc_btree.h"
34 #include "xfs_dir2_sf.h"
35 #include "xfs_attr_sf.h"
36 #include "xfs_dinode.h"
37 #include "xfs_inode.h"
38 #include "xfs_inode_item.h"
39 #include "xfs_alloc.h"
40 #include "xfs_btree.h"
41 #include "xfs_bmap.h"
42 #include "xfs_attr.h"
43 #include "xfs_attr_leaf.h"
44 #include "xfs_dir2_data.h"
45 #include "xfs_dir2_leaf.h"
46 #include "xfs_dir2_block.h"
47 #include "xfs_dir2_node.h"
48 #include "xfs_error.h"
51 * xfs_da_btree.c
53 * Routines to implement directories as Btrees of hashed names.
56 /*========================================================================
57 * Function prototypes for the kernel.
58 *========================================================================*/
61 * Routines used for growing the Btree.
63 STATIC int xfs_da_root_split(xfs_da_state_t *state,
64 xfs_da_state_blk_t *existing_root,
65 xfs_da_state_blk_t *new_child);
66 STATIC int xfs_da_node_split(xfs_da_state_t *state,
67 xfs_da_state_blk_t *existing_blk,
68 xfs_da_state_blk_t *split_blk,
69 xfs_da_state_blk_t *blk_to_add,
70 int treelevel,
71 int *result);
72 STATIC void xfs_da_node_rebalance(xfs_da_state_t *state,
73 xfs_da_state_blk_t *node_blk_1,
74 xfs_da_state_blk_t *node_blk_2);
75 STATIC void xfs_da_node_add(xfs_da_state_t *state,
76 xfs_da_state_blk_t *old_node_blk,
77 xfs_da_state_blk_t *new_node_blk);
80 * Routines used for shrinking the Btree.
82 STATIC int xfs_da_root_join(xfs_da_state_t *state,
83 xfs_da_state_blk_t *root_blk);
84 STATIC int xfs_da_node_toosmall(xfs_da_state_t *state, int *retval);
85 STATIC void xfs_da_node_remove(xfs_da_state_t *state,
86 xfs_da_state_blk_t *drop_blk);
87 STATIC void xfs_da_node_unbalance(xfs_da_state_t *state,
88 xfs_da_state_blk_t *src_node_blk,
89 xfs_da_state_blk_t *dst_node_blk);
92 * Utility routines.
94 STATIC uint xfs_da_node_lasthash(xfs_dabuf_t *bp, int *count);
95 STATIC int xfs_da_node_order(xfs_dabuf_t *node1_bp, xfs_dabuf_t *node2_bp);
96 STATIC xfs_dabuf_t *xfs_da_buf_make(int nbuf, xfs_buf_t **bps, inst_t *ra);
97 STATIC int xfs_da_blk_unlink(xfs_da_state_t *state,
98 xfs_da_state_blk_t *drop_blk,
99 xfs_da_state_blk_t *save_blk);
100 STATIC void xfs_da_state_kill_altpath(xfs_da_state_t *state);
102 /*========================================================================
103 * Routines used for growing the Btree.
104 *========================================================================*/
107 * Create the initial contents of an intermediate node.
110 xfs_da_node_create(xfs_da_args_t *args, xfs_dablk_t blkno, int level,
111 xfs_dabuf_t **bpp, int whichfork)
113 xfs_da_intnode_t *node;
114 xfs_dabuf_t *bp;
115 int error;
116 xfs_trans_t *tp;
118 tp = args->trans;
119 error = xfs_da_get_buf(tp, args->dp, blkno, -1, &bp, whichfork);
120 if (error)
121 return(error);
122 ASSERT(bp != NULL);
123 node = bp->data;
124 node->hdr.info.forw = 0;
125 node->hdr.info.back = 0;
126 node->hdr.info.magic = cpu_to_be16(XFS_DA_NODE_MAGIC);
127 node->hdr.info.pad = 0;
128 node->hdr.count = 0;
129 node->hdr.level = cpu_to_be16(level);
131 xfs_da_log_buf(tp, bp,
132 XFS_DA_LOGRANGE(node, &node->hdr, sizeof(node->hdr)));
134 *bpp = bp;
135 return(0);
139 * Split a leaf node, rebalance, then possibly split
140 * intermediate nodes, rebalance, etc.
142 int /* error */
143 xfs_da_split(xfs_da_state_t *state)
145 xfs_da_state_blk_t *oldblk, *newblk, *addblk;
146 xfs_da_intnode_t *node;
147 xfs_dabuf_t *bp;
148 int max, action, error, i;
151 * Walk back up the tree splitting/inserting/adjusting as necessary.
152 * If we need to insert and there isn't room, split the node, then
153 * decide which fragment to insert the new block from below into.
154 * Note that we may split the root this way, but we need more fixup.
156 max = state->path.active - 1;
157 ASSERT((max >= 0) && (max < XFS_DA_NODE_MAXDEPTH));
158 ASSERT(state->path.blk[max].magic == XFS_ATTR_LEAF_MAGIC ||
159 state->path.blk[max].magic == XFS_DIR2_LEAFN_MAGIC);
161 addblk = &state->path.blk[max]; /* initial dummy value */
162 for (i = max; (i >= 0) && addblk; state->path.active--, i--) {
163 oldblk = &state->path.blk[i];
164 newblk = &state->altpath.blk[i];
167 * If a leaf node then
168 * Allocate a new leaf node, then rebalance across them.
169 * else if an intermediate node then
170 * We split on the last layer, must we split the node?
172 switch (oldblk->magic) {
173 case XFS_ATTR_LEAF_MAGIC:
174 error = xfs_attr_leaf_split(state, oldblk, newblk);
175 if ((error != 0) && (error != ENOSPC)) {
176 return(error); /* GROT: attr is inconsistent */
178 if (!error) {
179 addblk = newblk;
180 break;
183 * Entry wouldn't fit, split the leaf again.
185 state->extravalid = 1;
186 if (state->inleaf) {
187 state->extraafter = 0; /* before newblk */
188 error = xfs_attr_leaf_split(state, oldblk,
189 &state->extrablk);
190 } else {
191 state->extraafter = 1; /* after newblk */
192 error = xfs_attr_leaf_split(state, newblk,
193 &state->extrablk);
195 if (error)
196 return(error); /* GROT: attr inconsistent */
197 addblk = newblk;
198 break;
199 case XFS_DIR2_LEAFN_MAGIC:
200 error = xfs_dir2_leafn_split(state, oldblk, newblk);
201 if (error)
202 return error;
203 addblk = newblk;
204 break;
205 case XFS_DA_NODE_MAGIC:
206 error = xfs_da_node_split(state, oldblk, newblk, addblk,
207 max - i, &action);
208 xfs_da_buf_done(addblk->bp);
209 addblk->bp = NULL;
210 if (error)
211 return(error); /* GROT: dir is inconsistent */
213 * Record the newly split block for the next time thru?
215 if (action)
216 addblk = newblk;
217 else
218 addblk = NULL;
219 break;
223 * Update the btree to show the new hashval for this child.
225 xfs_da_fixhashpath(state, &state->path);
227 * If we won't need this block again, it's getting dropped
228 * from the active path by the loop control, so we need
229 * to mark it done now.
231 if (i > 0 || !addblk)
232 xfs_da_buf_done(oldblk->bp);
234 if (!addblk)
235 return(0);
238 * Split the root node.
240 ASSERT(state->path.active == 0);
241 oldblk = &state->path.blk[0];
242 error = xfs_da_root_split(state, oldblk, addblk);
243 if (error) {
244 xfs_da_buf_done(oldblk->bp);
245 xfs_da_buf_done(addblk->bp);
246 addblk->bp = NULL;
247 return(error); /* GROT: dir is inconsistent */
251 * Update pointers to the node which used to be block 0 and
252 * just got bumped because of the addition of a new root node.
253 * There might be three blocks involved if a double split occurred,
254 * and the original block 0 could be at any position in the list.
257 node = oldblk->bp->data;
258 if (node->hdr.info.forw) {
259 if (be32_to_cpu(node->hdr.info.forw) == addblk->blkno) {
260 bp = addblk->bp;
261 } else {
262 ASSERT(state->extravalid);
263 bp = state->extrablk.bp;
265 node = bp->data;
266 node->hdr.info.back = cpu_to_be32(oldblk->blkno);
267 xfs_da_log_buf(state->args->trans, bp,
268 XFS_DA_LOGRANGE(node, &node->hdr.info,
269 sizeof(node->hdr.info)));
271 node = oldblk->bp->data;
272 if (node->hdr.info.back) {
273 if (be32_to_cpu(node->hdr.info.back) == addblk->blkno) {
274 bp = addblk->bp;
275 } else {
276 ASSERT(state->extravalid);
277 bp = state->extrablk.bp;
279 node = bp->data;
280 node->hdr.info.forw = cpu_to_be32(oldblk->blkno);
281 xfs_da_log_buf(state->args->trans, bp,
282 XFS_DA_LOGRANGE(node, &node->hdr.info,
283 sizeof(node->hdr.info)));
285 xfs_da_buf_done(oldblk->bp);
286 xfs_da_buf_done(addblk->bp);
287 addblk->bp = NULL;
288 return(0);
292 * Split the root. We have to create a new root and point to the two
293 * parts (the split old root) that we just created. Copy block zero to
294 * the EOF, extending the inode in process.
296 STATIC int /* error */
297 xfs_da_root_split(xfs_da_state_t *state, xfs_da_state_blk_t *blk1,
298 xfs_da_state_blk_t *blk2)
300 xfs_da_intnode_t *node, *oldroot;
301 xfs_da_args_t *args;
302 xfs_dablk_t blkno;
303 xfs_dabuf_t *bp;
304 int error, size;
305 xfs_inode_t *dp;
306 xfs_trans_t *tp;
307 xfs_mount_t *mp;
308 xfs_dir2_leaf_t *leaf;
311 * Copy the existing (incorrect) block from the root node position
312 * to a free space somewhere.
314 args = state->args;
315 ASSERT(args != NULL);
316 error = xfs_da_grow_inode(args, &blkno);
317 if (error)
318 return(error);
319 dp = args->dp;
320 tp = args->trans;
321 mp = state->mp;
322 error = xfs_da_get_buf(tp, dp, blkno, -1, &bp, args->whichfork);
323 if (error)
324 return(error);
325 ASSERT(bp != NULL);
326 node = bp->data;
327 oldroot = blk1->bp->data;
328 if (be16_to_cpu(oldroot->hdr.info.magic) == XFS_DA_NODE_MAGIC) {
329 size = (int)((char *)&oldroot->btree[be16_to_cpu(oldroot->hdr.count)] -
330 (char *)oldroot);
331 } else {
332 ASSERT(be16_to_cpu(oldroot->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC);
333 leaf = (xfs_dir2_leaf_t *)oldroot;
334 size = (int)((char *)&leaf->ents[be16_to_cpu(leaf->hdr.count)] -
335 (char *)leaf);
337 memcpy(node, oldroot, size);
338 xfs_da_log_buf(tp, bp, 0, size - 1);
339 xfs_da_buf_done(blk1->bp);
340 blk1->bp = bp;
341 blk1->blkno = blkno;
344 * Set up the new root node.
346 error = xfs_da_node_create(args,
347 (args->whichfork == XFS_DATA_FORK) ? mp->m_dirleafblk : 0,
348 be16_to_cpu(node->hdr.level) + 1, &bp, args->whichfork);
349 if (error)
350 return(error);
351 node = bp->data;
352 node->btree[0].hashval = cpu_to_be32(blk1->hashval);
353 node->btree[0].before = cpu_to_be32(blk1->blkno);
354 node->btree[1].hashval = cpu_to_be32(blk2->hashval);
355 node->btree[1].before = cpu_to_be32(blk2->blkno);
356 node->hdr.count = cpu_to_be16(2);
358 #ifdef DEBUG
359 if (be16_to_cpu(oldroot->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC) {
360 ASSERT(blk1->blkno >= mp->m_dirleafblk &&
361 blk1->blkno < mp->m_dirfreeblk);
362 ASSERT(blk2->blkno >= mp->m_dirleafblk &&
363 blk2->blkno < mp->m_dirfreeblk);
365 #endif
367 /* Header is already logged by xfs_da_node_create */
368 xfs_da_log_buf(tp, bp,
369 XFS_DA_LOGRANGE(node, node->btree,
370 sizeof(xfs_da_node_entry_t) * 2));
371 xfs_da_buf_done(bp);
373 return(0);
377 * Split the node, rebalance, then add the new entry.
379 STATIC int /* error */
380 xfs_da_node_split(xfs_da_state_t *state, xfs_da_state_blk_t *oldblk,
381 xfs_da_state_blk_t *newblk,
382 xfs_da_state_blk_t *addblk,
383 int treelevel, int *result)
385 xfs_da_intnode_t *node;
386 xfs_dablk_t blkno;
387 int newcount, error;
388 int useextra;
390 node = oldblk->bp->data;
391 ASSERT(be16_to_cpu(node->hdr.info.magic) == XFS_DA_NODE_MAGIC);
394 * With V2 dirs the extra block is data or freespace.
396 useextra = state->extravalid && state->args->whichfork == XFS_ATTR_FORK;
397 newcount = 1 + useextra;
399 * Do we have to split the node?
401 if ((be16_to_cpu(node->hdr.count) + newcount) > state->node_ents) {
403 * Allocate a new node, add to the doubly linked chain of
404 * nodes, then move some of our excess entries into it.
406 error = xfs_da_grow_inode(state->args, &blkno);
407 if (error)
408 return(error); /* GROT: dir is inconsistent */
410 error = xfs_da_node_create(state->args, blkno, treelevel,
411 &newblk->bp, state->args->whichfork);
412 if (error)
413 return(error); /* GROT: dir is inconsistent */
414 newblk->blkno = blkno;
415 newblk->magic = XFS_DA_NODE_MAGIC;
416 xfs_da_node_rebalance(state, oldblk, newblk);
417 error = xfs_da_blk_link(state, oldblk, newblk);
418 if (error)
419 return(error);
420 *result = 1;
421 } else {
422 *result = 0;
426 * Insert the new entry(s) into the correct block
427 * (updating last hashval in the process).
429 * xfs_da_node_add() inserts BEFORE the given index,
430 * and as a result of using node_lookup_int() we always
431 * point to a valid entry (not after one), but a split
432 * operation always results in a new block whose hashvals
433 * FOLLOW the current block.
435 * If we had double-split op below us, then add the extra block too.
437 node = oldblk->bp->data;
438 if (oldblk->index <= be16_to_cpu(node->hdr.count)) {
439 oldblk->index++;
440 xfs_da_node_add(state, oldblk, addblk);
441 if (useextra) {
442 if (state->extraafter)
443 oldblk->index++;
444 xfs_da_node_add(state, oldblk, &state->extrablk);
445 state->extravalid = 0;
447 } else {
448 newblk->index++;
449 xfs_da_node_add(state, newblk, addblk);
450 if (useextra) {
451 if (state->extraafter)
452 newblk->index++;
453 xfs_da_node_add(state, newblk, &state->extrablk);
454 state->extravalid = 0;
458 return(0);
462 * Balance the btree elements between two intermediate nodes,
463 * usually one full and one empty.
465 * NOTE: if blk2 is empty, then it will get the upper half of blk1.
467 STATIC void
468 xfs_da_node_rebalance(xfs_da_state_t *state, xfs_da_state_blk_t *blk1,
469 xfs_da_state_blk_t *blk2)
471 xfs_da_intnode_t *node1, *node2, *tmpnode;
472 xfs_da_node_entry_t *btree_s, *btree_d;
473 int count, tmp;
474 xfs_trans_t *tp;
476 node1 = blk1->bp->data;
477 node2 = blk2->bp->data;
479 * Figure out how many entries need to move, and in which direction.
480 * Swap the nodes around if that makes it simpler.
482 if ((be16_to_cpu(node1->hdr.count) > 0) && (be16_to_cpu(node2->hdr.count) > 0) &&
483 ((be32_to_cpu(node2->btree[0].hashval) < be32_to_cpu(node1->btree[0].hashval)) ||
484 (be32_to_cpu(node2->btree[be16_to_cpu(node2->hdr.count)-1].hashval) <
485 be32_to_cpu(node1->btree[be16_to_cpu(node1->hdr.count)-1].hashval)))) {
486 tmpnode = node1;
487 node1 = node2;
488 node2 = tmpnode;
490 ASSERT(be16_to_cpu(node1->hdr.info.magic) == XFS_DA_NODE_MAGIC);
491 ASSERT(be16_to_cpu(node2->hdr.info.magic) == XFS_DA_NODE_MAGIC);
492 count = (be16_to_cpu(node1->hdr.count) - be16_to_cpu(node2->hdr.count)) / 2;
493 if (count == 0)
494 return;
495 tp = state->args->trans;
497 * Two cases: high-to-low and low-to-high.
499 if (count > 0) {
501 * Move elements in node2 up to make a hole.
503 if ((tmp = be16_to_cpu(node2->hdr.count)) > 0) {
504 tmp *= (uint)sizeof(xfs_da_node_entry_t);
505 btree_s = &node2->btree[0];
506 btree_d = &node2->btree[count];
507 memmove(btree_d, btree_s, tmp);
511 * Move the req'd B-tree elements from high in node1 to
512 * low in node2.
514 be16_add(&node2->hdr.count, count);
515 tmp = count * (uint)sizeof(xfs_da_node_entry_t);
516 btree_s = &node1->btree[be16_to_cpu(node1->hdr.count) - count];
517 btree_d = &node2->btree[0];
518 memcpy(btree_d, btree_s, tmp);
519 be16_add(&node1->hdr.count, -count);
520 } else {
522 * Move the req'd B-tree elements from low in node2 to
523 * high in node1.
525 count = -count;
526 tmp = count * (uint)sizeof(xfs_da_node_entry_t);
527 btree_s = &node2->btree[0];
528 btree_d = &node1->btree[be16_to_cpu(node1->hdr.count)];
529 memcpy(btree_d, btree_s, tmp);
530 be16_add(&node1->hdr.count, count);
531 xfs_da_log_buf(tp, blk1->bp,
532 XFS_DA_LOGRANGE(node1, btree_d, tmp));
535 * Move elements in node2 down to fill the hole.
537 tmp = be16_to_cpu(node2->hdr.count) - count;
538 tmp *= (uint)sizeof(xfs_da_node_entry_t);
539 btree_s = &node2->btree[count];
540 btree_d = &node2->btree[0];
541 memmove(btree_d, btree_s, tmp);
542 be16_add(&node2->hdr.count, -count);
546 * Log header of node 1 and all current bits of node 2.
548 xfs_da_log_buf(tp, blk1->bp,
549 XFS_DA_LOGRANGE(node1, &node1->hdr, sizeof(node1->hdr)));
550 xfs_da_log_buf(tp, blk2->bp,
551 XFS_DA_LOGRANGE(node2, &node2->hdr,
552 sizeof(node2->hdr) +
553 sizeof(node2->btree[0]) * be16_to_cpu(node2->hdr.count)));
556 * Record the last hashval from each block for upward propagation.
557 * (note: don't use the swapped node pointers)
559 node1 = blk1->bp->data;
560 node2 = blk2->bp->data;
561 blk1->hashval = be32_to_cpu(node1->btree[be16_to_cpu(node1->hdr.count)-1].hashval);
562 blk2->hashval = be32_to_cpu(node2->btree[be16_to_cpu(node2->hdr.count)-1].hashval);
565 * Adjust the expected index for insertion.
567 if (blk1->index >= be16_to_cpu(node1->hdr.count)) {
568 blk2->index = blk1->index - be16_to_cpu(node1->hdr.count);
569 blk1->index = be16_to_cpu(node1->hdr.count) + 1; /* make it invalid */
574 * Add a new entry to an intermediate node.
576 STATIC void
577 xfs_da_node_add(xfs_da_state_t *state, xfs_da_state_blk_t *oldblk,
578 xfs_da_state_blk_t *newblk)
580 xfs_da_intnode_t *node;
581 xfs_da_node_entry_t *btree;
582 int tmp;
583 xfs_mount_t *mp;
585 node = oldblk->bp->data;
586 mp = state->mp;
587 ASSERT(be16_to_cpu(node->hdr.info.magic) == XFS_DA_NODE_MAGIC);
588 ASSERT((oldblk->index >= 0) && (oldblk->index <= be16_to_cpu(node->hdr.count)));
589 ASSERT(newblk->blkno != 0);
590 if (state->args->whichfork == XFS_DATA_FORK)
591 ASSERT(newblk->blkno >= mp->m_dirleafblk &&
592 newblk->blkno < mp->m_dirfreeblk);
595 * We may need to make some room before we insert the new node.
597 tmp = 0;
598 btree = &node->btree[ oldblk->index ];
599 if (oldblk->index < be16_to_cpu(node->hdr.count)) {
600 tmp = (be16_to_cpu(node->hdr.count) - oldblk->index) * (uint)sizeof(*btree);
601 memmove(btree + 1, btree, tmp);
603 btree->hashval = cpu_to_be32(newblk->hashval);
604 btree->before = cpu_to_be32(newblk->blkno);
605 xfs_da_log_buf(state->args->trans, oldblk->bp,
606 XFS_DA_LOGRANGE(node, btree, tmp + sizeof(*btree)));
607 be16_add(&node->hdr.count, 1);
608 xfs_da_log_buf(state->args->trans, oldblk->bp,
609 XFS_DA_LOGRANGE(node, &node->hdr, sizeof(node->hdr)));
612 * Copy the last hash value from the oldblk to propagate upwards.
614 oldblk->hashval = be32_to_cpu(node->btree[be16_to_cpu(node->hdr.count)-1 ].hashval);
617 /*========================================================================
618 * Routines used for shrinking the Btree.
619 *========================================================================*/
622 * Deallocate an empty leaf node, remove it from its parent,
623 * possibly deallocating that block, etc...
626 xfs_da_join(xfs_da_state_t *state)
628 xfs_da_state_blk_t *drop_blk, *save_blk;
629 int action, error;
631 action = 0;
632 drop_blk = &state->path.blk[ state->path.active-1 ];
633 save_blk = &state->altpath.blk[ state->path.active-1 ];
634 ASSERT(state->path.blk[0].magic == XFS_DA_NODE_MAGIC);
635 ASSERT(drop_blk->magic == XFS_ATTR_LEAF_MAGIC ||
636 drop_blk->magic == XFS_DIR2_LEAFN_MAGIC);
639 * Walk back up the tree joining/deallocating as necessary.
640 * When we stop dropping blocks, break out.
642 for ( ; state->path.active >= 2; drop_blk--, save_blk--,
643 state->path.active--) {
645 * See if we can combine the block with a neighbor.
646 * (action == 0) => no options, just leave
647 * (action == 1) => coalesce, then unlink
648 * (action == 2) => block empty, unlink it
650 switch (drop_blk->magic) {
651 case XFS_ATTR_LEAF_MAGIC:
652 error = xfs_attr_leaf_toosmall(state, &action);
653 if (error)
654 return(error);
655 if (action == 0)
656 return(0);
657 xfs_attr_leaf_unbalance(state, drop_blk, save_blk);
658 break;
659 case XFS_DIR2_LEAFN_MAGIC:
660 error = xfs_dir2_leafn_toosmall(state, &action);
661 if (error)
662 return error;
663 if (action == 0)
664 return 0;
665 xfs_dir2_leafn_unbalance(state, drop_blk, save_blk);
666 break;
667 case XFS_DA_NODE_MAGIC:
669 * Remove the offending node, fixup hashvals,
670 * check for a toosmall neighbor.
672 xfs_da_node_remove(state, drop_blk);
673 xfs_da_fixhashpath(state, &state->path);
674 error = xfs_da_node_toosmall(state, &action);
675 if (error)
676 return(error);
677 if (action == 0)
678 return 0;
679 xfs_da_node_unbalance(state, drop_blk, save_blk);
680 break;
682 xfs_da_fixhashpath(state, &state->altpath);
683 error = xfs_da_blk_unlink(state, drop_blk, save_blk);
684 xfs_da_state_kill_altpath(state);
685 if (error)
686 return(error);
687 error = xfs_da_shrink_inode(state->args, drop_blk->blkno,
688 drop_blk->bp);
689 drop_blk->bp = NULL;
690 if (error)
691 return(error);
694 * We joined all the way to the top. If it turns out that
695 * we only have one entry in the root, make the child block
696 * the new root.
698 xfs_da_node_remove(state, drop_blk);
699 xfs_da_fixhashpath(state, &state->path);
700 error = xfs_da_root_join(state, &state->path.blk[0]);
701 return(error);
705 * We have only one entry in the root. Copy the only remaining child of
706 * the old root to block 0 as the new root node.
708 STATIC int
709 xfs_da_root_join(xfs_da_state_t *state, xfs_da_state_blk_t *root_blk)
711 xfs_da_intnode_t *oldroot;
712 /* REFERENCED */
713 xfs_da_blkinfo_t *blkinfo;
714 xfs_da_args_t *args;
715 xfs_dablk_t child;
716 xfs_dabuf_t *bp;
717 int error;
719 args = state->args;
720 ASSERT(args != NULL);
721 ASSERT(root_blk->magic == XFS_DA_NODE_MAGIC);
722 oldroot = root_blk->bp->data;
723 ASSERT(be16_to_cpu(oldroot->hdr.info.magic) == XFS_DA_NODE_MAGIC);
724 ASSERT(!oldroot->hdr.info.forw);
725 ASSERT(!oldroot->hdr.info.back);
728 * If the root has more than one child, then don't do anything.
730 if (be16_to_cpu(oldroot->hdr.count) > 1)
731 return(0);
734 * Read in the (only) child block, then copy those bytes into
735 * the root block's buffer and free the original child block.
737 child = be32_to_cpu(oldroot->btree[0].before);
738 ASSERT(child != 0);
739 error = xfs_da_read_buf(args->trans, args->dp, child, -1, &bp,
740 args->whichfork);
741 if (error)
742 return(error);
743 ASSERT(bp != NULL);
744 blkinfo = bp->data;
745 if (be16_to_cpu(oldroot->hdr.level) == 1) {
746 ASSERT(be16_to_cpu(blkinfo->magic) == XFS_DIR2_LEAFN_MAGIC ||
747 be16_to_cpu(blkinfo->magic) == XFS_ATTR_LEAF_MAGIC);
748 } else {
749 ASSERT(be16_to_cpu(blkinfo->magic) == XFS_DA_NODE_MAGIC);
751 ASSERT(!blkinfo->forw);
752 ASSERT(!blkinfo->back);
753 memcpy(root_blk->bp->data, bp->data, state->blocksize);
754 xfs_da_log_buf(args->trans, root_blk->bp, 0, state->blocksize - 1);
755 error = xfs_da_shrink_inode(args, child, bp);
756 return(error);
760 * Check a node block and its neighbors to see if the block should be
761 * collapsed into one or the other neighbor. Always keep the block
762 * with the smaller block number.
763 * If the current block is over 50% full, don't try to join it, return 0.
764 * If the block is empty, fill in the state structure and return 2.
765 * If it can be collapsed, fill in the state structure and return 1.
766 * If nothing can be done, return 0.
768 STATIC int
769 xfs_da_node_toosmall(xfs_da_state_t *state, int *action)
771 xfs_da_intnode_t *node;
772 xfs_da_state_blk_t *blk;
773 xfs_da_blkinfo_t *info;
774 int count, forward, error, retval, i;
775 xfs_dablk_t blkno;
776 xfs_dabuf_t *bp;
779 * Check for the degenerate case of the block being over 50% full.
780 * If so, it's not worth even looking to see if we might be able
781 * to coalesce with a sibling.
783 blk = &state->path.blk[ state->path.active-1 ];
784 info = blk->bp->data;
785 ASSERT(be16_to_cpu(info->magic) == XFS_DA_NODE_MAGIC);
786 node = (xfs_da_intnode_t *)info;
787 count = be16_to_cpu(node->hdr.count);
788 if (count > (state->node_ents >> 1)) {
789 *action = 0; /* blk over 50%, don't try to join */
790 return(0); /* blk over 50%, don't try to join */
794 * Check for the degenerate case of the block being empty.
795 * If the block is empty, we'll simply delete it, no need to
796 * coalesce it with a sibling block. We choose (arbitrarily)
797 * to merge with the forward block unless it is NULL.
799 if (count == 0) {
801 * Make altpath point to the block we want to keep and
802 * path point to the block we want to drop (this one).
804 forward = (info->forw != 0);
805 memcpy(&state->altpath, &state->path, sizeof(state->path));
806 error = xfs_da_path_shift(state, &state->altpath, forward,
807 0, &retval);
808 if (error)
809 return(error);
810 if (retval) {
811 *action = 0;
812 } else {
813 *action = 2;
815 return(0);
819 * Examine each sibling block to see if we can coalesce with
820 * at least 25% free space to spare. We need to figure out
821 * whether to merge with the forward or the backward block.
822 * We prefer coalescing with the lower numbered sibling so as
823 * to shrink a directory over time.
825 /* start with smaller blk num */
826 forward = (be32_to_cpu(info->forw) < be32_to_cpu(info->back));
827 for (i = 0; i < 2; forward = !forward, i++) {
828 if (forward)
829 blkno = be32_to_cpu(info->forw);
830 else
831 blkno = be32_to_cpu(info->back);
832 if (blkno == 0)
833 continue;
834 error = xfs_da_read_buf(state->args->trans, state->args->dp,
835 blkno, -1, &bp, state->args->whichfork);
836 if (error)
837 return(error);
838 ASSERT(bp != NULL);
840 node = (xfs_da_intnode_t *)info;
841 count = state->node_ents;
842 count -= state->node_ents >> 2;
843 count -= be16_to_cpu(node->hdr.count);
844 node = bp->data;
845 ASSERT(be16_to_cpu(node->hdr.info.magic) == XFS_DA_NODE_MAGIC);
846 count -= be16_to_cpu(node->hdr.count);
847 xfs_da_brelse(state->args->trans, bp);
848 if (count >= 0)
849 break; /* fits with at least 25% to spare */
851 if (i >= 2) {
852 *action = 0;
853 return(0);
857 * Make altpath point to the block we want to keep (the lower
858 * numbered block) and path point to the block we want to drop.
860 memcpy(&state->altpath, &state->path, sizeof(state->path));
861 if (blkno < blk->blkno) {
862 error = xfs_da_path_shift(state, &state->altpath, forward,
863 0, &retval);
864 if (error) {
865 return(error);
867 if (retval) {
868 *action = 0;
869 return(0);
871 } else {
872 error = xfs_da_path_shift(state, &state->path, forward,
873 0, &retval);
874 if (error) {
875 return(error);
877 if (retval) {
878 *action = 0;
879 return(0);
882 *action = 1;
883 return(0);
887 * Walk back up the tree adjusting hash values as necessary,
888 * when we stop making changes, return.
890 void
891 xfs_da_fixhashpath(xfs_da_state_t *state, xfs_da_state_path_t *path)
893 xfs_da_state_blk_t *blk;
894 xfs_da_intnode_t *node;
895 xfs_da_node_entry_t *btree;
896 xfs_dahash_t lasthash=0;
897 int level, count;
899 level = path->active-1;
900 blk = &path->blk[ level ];
901 switch (blk->magic) {
902 case XFS_ATTR_LEAF_MAGIC:
903 lasthash = xfs_attr_leaf_lasthash(blk->bp, &count);
904 if (count == 0)
905 return;
906 break;
907 case XFS_DIR2_LEAFN_MAGIC:
908 lasthash = xfs_dir2_leafn_lasthash(blk->bp, &count);
909 if (count == 0)
910 return;
911 break;
912 case XFS_DA_NODE_MAGIC:
913 lasthash = xfs_da_node_lasthash(blk->bp, &count);
914 if (count == 0)
915 return;
916 break;
918 for (blk--, level--; level >= 0; blk--, level--) {
919 node = blk->bp->data;
920 ASSERT(be16_to_cpu(node->hdr.info.magic) == XFS_DA_NODE_MAGIC);
921 btree = &node->btree[ blk->index ];
922 if (be32_to_cpu(btree->hashval) == lasthash)
923 break;
924 blk->hashval = lasthash;
925 btree->hashval = cpu_to_be32(lasthash);
926 xfs_da_log_buf(state->args->trans, blk->bp,
927 XFS_DA_LOGRANGE(node, btree, sizeof(*btree)));
929 lasthash = be32_to_cpu(node->btree[be16_to_cpu(node->hdr.count)-1].hashval);
934 * Remove an entry from an intermediate node.
936 STATIC void
937 xfs_da_node_remove(xfs_da_state_t *state, xfs_da_state_blk_t *drop_blk)
939 xfs_da_intnode_t *node;
940 xfs_da_node_entry_t *btree;
941 int tmp;
943 node = drop_blk->bp->data;
944 ASSERT(drop_blk->index < be16_to_cpu(node->hdr.count));
945 ASSERT(drop_blk->index >= 0);
948 * Copy over the offending entry, or just zero it out.
950 btree = &node->btree[drop_blk->index];
951 if (drop_blk->index < (be16_to_cpu(node->hdr.count)-1)) {
952 tmp = be16_to_cpu(node->hdr.count) - drop_blk->index - 1;
953 tmp *= (uint)sizeof(xfs_da_node_entry_t);
954 memmove(btree, btree + 1, tmp);
955 xfs_da_log_buf(state->args->trans, drop_blk->bp,
956 XFS_DA_LOGRANGE(node, btree, tmp));
957 btree = &node->btree[be16_to_cpu(node->hdr.count)-1];
959 memset((char *)btree, 0, sizeof(xfs_da_node_entry_t));
960 xfs_da_log_buf(state->args->trans, drop_blk->bp,
961 XFS_DA_LOGRANGE(node, btree, sizeof(*btree)));
962 be16_add(&node->hdr.count, -1);
963 xfs_da_log_buf(state->args->trans, drop_blk->bp,
964 XFS_DA_LOGRANGE(node, &node->hdr, sizeof(node->hdr)));
967 * Copy the last hash value from the block to propagate upwards.
969 btree--;
970 drop_blk->hashval = be32_to_cpu(btree->hashval);
974 * Unbalance the btree elements between two intermediate nodes,
975 * move all Btree elements from one node into another.
977 STATIC void
978 xfs_da_node_unbalance(xfs_da_state_t *state, xfs_da_state_blk_t *drop_blk,
979 xfs_da_state_blk_t *save_blk)
981 xfs_da_intnode_t *drop_node, *save_node;
982 xfs_da_node_entry_t *btree;
983 int tmp;
984 xfs_trans_t *tp;
986 drop_node = drop_blk->bp->data;
987 save_node = save_blk->bp->data;
988 ASSERT(be16_to_cpu(drop_node->hdr.info.magic) == XFS_DA_NODE_MAGIC);
989 ASSERT(be16_to_cpu(save_node->hdr.info.magic) == XFS_DA_NODE_MAGIC);
990 tp = state->args->trans;
993 * If the dying block has lower hashvals, then move all the
994 * elements in the remaining block up to make a hole.
996 if ((be32_to_cpu(drop_node->btree[0].hashval) < be32_to_cpu(save_node->btree[ 0 ].hashval)) ||
997 (be32_to_cpu(drop_node->btree[be16_to_cpu(drop_node->hdr.count)-1].hashval) <
998 be32_to_cpu(save_node->btree[be16_to_cpu(save_node->hdr.count)-1].hashval)))
1000 btree = &save_node->btree[be16_to_cpu(drop_node->hdr.count)];
1001 tmp = be16_to_cpu(save_node->hdr.count) * (uint)sizeof(xfs_da_node_entry_t);
1002 memmove(btree, &save_node->btree[0], tmp);
1003 btree = &save_node->btree[0];
1004 xfs_da_log_buf(tp, save_blk->bp,
1005 XFS_DA_LOGRANGE(save_node, btree,
1006 (be16_to_cpu(save_node->hdr.count) + be16_to_cpu(drop_node->hdr.count)) *
1007 sizeof(xfs_da_node_entry_t)));
1008 } else {
1009 btree = &save_node->btree[be16_to_cpu(save_node->hdr.count)];
1010 xfs_da_log_buf(tp, save_blk->bp,
1011 XFS_DA_LOGRANGE(save_node, btree,
1012 be16_to_cpu(drop_node->hdr.count) *
1013 sizeof(xfs_da_node_entry_t)));
1017 * Move all the B-tree elements from drop_blk to save_blk.
1019 tmp = be16_to_cpu(drop_node->hdr.count) * (uint)sizeof(xfs_da_node_entry_t);
1020 memcpy(btree, &drop_node->btree[0], tmp);
1021 be16_add(&save_node->hdr.count, be16_to_cpu(drop_node->hdr.count));
1023 xfs_da_log_buf(tp, save_blk->bp,
1024 XFS_DA_LOGRANGE(save_node, &save_node->hdr,
1025 sizeof(save_node->hdr)));
1028 * Save the last hashval in the remaining block for upward propagation.
1030 save_blk->hashval = be32_to_cpu(save_node->btree[be16_to_cpu(save_node->hdr.count)-1].hashval);
1033 /*========================================================================
1034 * Routines used for finding things in the Btree.
1035 *========================================================================*/
1038 * Walk down the Btree looking for a particular filename, filling
1039 * in the state structure as we go.
1041 * We will set the state structure to point to each of the elements
1042 * in each of the nodes where either the hashval is or should be.
1044 * We support duplicate hashval's so for each entry in the current
1045 * node that could contain the desired hashval, descend. This is a
1046 * pruned depth-first tree search.
1048 int /* error */
1049 xfs_da_node_lookup_int(xfs_da_state_t *state, int *result)
1051 xfs_da_state_blk_t *blk;
1052 xfs_da_blkinfo_t *curr;
1053 xfs_da_intnode_t *node;
1054 xfs_da_node_entry_t *btree;
1055 xfs_dablk_t blkno;
1056 int probe, span, max, error, retval;
1057 xfs_dahash_t hashval, btreehashval;
1058 xfs_da_args_t *args;
1060 args = state->args;
1063 * Descend thru the B-tree searching each level for the right
1064 * node to use, until the right hashval is found.
1066 blkno = (args->whichfork == XFS_DATA_FORK)? state->mp->m_dirleafblk : 0;
1067 for (blk = &state->path.blk[0], state->path.active = 1;
1068 state->path.active <= XFS_DA_NODE_MAXDEPTH;
1069 blk++, state->path.active++) {
1071 * Read the next node down in the tree.
1073 blk->blkno = blkno;
1074 error = xfs_da_read_buf(args->trans, args->dp, blkno,
1075 -1, &blk->bp, args->whichfork);
1076 if (error) {
1077 blk->blkno = 0;
1078 state->path.active--;
1079 return(error);
1081 curr = blk->bp->data;
1082 blk->magic = be16_to_cpu(curr->magic);
1083 ASSERT(blk->magic == XFS_DA_NODE_MAGIC ||
1084 blk->magic == XFS_DIR2_LEAFN_MAGIC ||
1085 blk->magic == XFS_ATTR_LEAF_MAGIC);
1088 * Search an intermediate node for a match.
1090 if (blk->magic == XFS_DA_NODE_MAGIC) {
1091 node = blk->bp->data;
1092 max = be16_to_cpu(node->hdr.count);
1093 btreehashval = node->btree[max-1].hashval;
1094 blk->hashval = be32_to_cpu(btreehashval);
1097 * Binary search. (note: small blocks will skip loop)
1099 probe = span = max / 2;
1100 hashval = args->hashval;
1101 for (btree = &node->btree[probe]; span > 4;
1102 btree = &node->btree[probe]) {
1103 span /= 2;
1104 btreehashval = be32_to_cpu(btree->hashval);
1105 if (btreehashval < hashval)
1106 probe += span;
1107 else if (btreehashval > hashval)
1108 probe -= span;
1109 else
1110 break;
1112 ASSERT((probe >= 0) && (probe < max));
1113 ASSERT((span <= 4) || (be32_to_cpu(btree->hashval) == hashval));
1116 * Since we may have duplicate hashval's, find the first
1117 * matching hashval in the node.
1119 while ((probe > 0) && (be32_to_cpu(btree->hashval) >= hashval)) {
1120 btree--;
1121 probe--;
1123 while ((probe < max) && (be32_to_cpu(btree->hashval) < hashval)) {
1124 btree++;
1125 probe++;
1129 * Pick the right block to descend on.
1131 if (probe == max) {
1132 blk->index = max-1;
1133 blkno = be32_to_cpu(node->btree[max-1].before);
1134 } else {
1135 blk->index = probe;
1136 blkno = be32_to_cpu(btree->before);
1138 } else if (blk->magic == XFS_ATTR_LEAF_MAGIC) {
1139 blk->hashval = xfs_attr_leaf_lasthash(blk->bp, NULL);
1140 break;
1141 } else if (blk->magic == XFS_DIR2_LEAFN_MAGIC) {
1142 blk->hashval = xfs_dir2_leafn_lasthash(blk->bp, NULL);
1143 break;
1148 * A leaf block that ends in the hashval that we are interested in
1149 * (final hashval == search hashval) means that the next block may
1150 * contain more entries with the same hashval, shift upward to the
1151 * next leaf and keep searching.
1153 for (;;) {
1154 if (blk->magic == XFS_DIR2_LEAFN_MAGIC) {
1155 retval = xfs_dir2_leafn_lookup_int(blk->bp, args,
1156 &blk->index, state);
1157 } else if (blk->magic == XFS_ATTR_LEAF_MAGIC) {
1158 retval = xfs_attr_leaf_lookup_int(blk->bp, args);
1159 blk->index = args->index;
1160 args->blkno = blk->blkno;
1161 } else {
1162 ASSERT(0);
1163 return XFS_ERROR(EFSCORRUPTED);
1165 if (((retval == ENOENT) || (retval == ENOATTR)) &&
1166 (blk->hashval == args->hashval)) {
1167 error = xfs_da_path_shift(state, &state->path, 1, 1,
1168 &retval);
1169 if (error)
1170 return(error);
1171 if (retval == 0) {
1172 continue;
1173 } else if (blk->magic == XFS_ATTR_LEAF_MAGIC) {
1174 /* path_shift() gives ENOENT */
1175 retval = XFS_ERROR(ENOATTR);
1178 break;
1180 *result = retval;
1181 return(0);
1184 /*========================================================================
1185 * Utility routines.
1186 *========================================================================*/
1189 * Link a new block into a doubly linked list of blocks (of whatever type).
1191 int /* error */
1192 xfs_da_blk_link(xfs_da_state_t *state, xfs_da_state_blk_t *old_blk,
1193 xfs_da_state_blk_t *new_blk)
1195 xfs_da_blkinfo_t *old_info, *new_info, *tmp_info;
1196 xfs_da_args_t *args;
1197 int before=0, error;
1198 xfs_dabuf_t *bp;
1201 * Set up environment.
1203 args = state->args;
1204 ASSERT(args != NULL);
1205 old_info = old_blk->bp->data;
1206 new_info = new_blk->bp->data;
1207 ASSERT(old_blk->magic == XFS_DA_NODE_MAGIC ||
1208 old_blk->magic == XFS_DIR2_LEAFN_MAGIC ||
1209 old_blk->magic == XFS_ATTR_LEAF_MAGIC);
1210 ASSERT(old_blk->magic == be16_to_cpu(old_info->magic));
1211 ASSERT(new_blk->magic == be16_to_cpu(new_info->magic));
1212 ASSERT(old_blk->magic == new_blk->magic);
1214 switch (old_blk->magic) {
1215 case XFS_ATTR_LEAF_MAGIC:
1216 before = xfs_attr_leaf_order(old_blk->bp, new_blk->bp);
1217 break;
1218 case XFS_DIR2_LEAFN_MAGIC:
1219 before = xfs_dir2_leafn_order(old_blk->bp, new_blk->bp);
1220 break;
1221 case XFS_DA_NODE_MAGIC:
1222 before = xfs_da_node_order(old_blk->bp, new_blk->bp);
1223 break;
1227 * Link blocks in appropriate order.
1229 if (before) {
1231 * Link new block in before existing block.
1233 new_info->forw = cpu_to_be32(old_blk->blkno);
1234 new_info->back = old_info->back;
1235 if (old_info->back) {
1236 error = xfs_da_read_buf(args->trans, args->dp,
1237 be32_to_cpu(old_info->back),
1238 -1, &bp, args->whichfork);
1239 if (error)
1240 return(error);
1241 ASSERT(bp != NULL);
1242 tmp_info = bp->data;
1243 ASSERT(be16_to_cpu(tmp_info->magic) == be16_to_cpu(old_info->magic));
1244 ASSERT(be32_to_cpu(tmp_info->forw) == old_blk->blkno);
1245 tmp_info->forw = cpu_to_be32(new_blk->blkno);
1246 xfs_da_log_buf(args->trans, bp, 0, sizeof(*tmp_info)-1);
1247 xfs_da_buf_done(bp);
1249 old_info->back = cpu_to_be32(new_blk->blkno);
1250 } else {
1252 * Link new block in after existing block.
1254 new_info->forw = old_info->forw;
1255 new_info->back = cpu_to_be32(old_blk->blkno);
1256 if (old_info->forw) {
1257 error = xfs_da_read_buf(args->trans, args->dp,
1258 be32_to_cpu(old_info->forw),
1259 -1, &bp, args->whichfork);
1260 if (error)
1261 return(error);
1262 ASSERT(bp != NULL);
1263 tmp_info = bp->data;
1264 ASSERT(tmp_info->magic == old_info->magic);
1265 ASSERT(be32_to_cpu(tmp_info->back) == old_blk->blkno);
1266 tmp_info->back = cpu_to_be32(new_blk->blkno);
1267 xfs_da_log_buf(args->trans, bp, 0, sizeof(*tmp_info)-1);
1268 xfs_da_buf_done(bp);
1270 old_info->forw = cpu_to_be32(new_blk->blkno);
1273 xfs_da_log_buf(args->trans, old_blk->bp, 0, sizeof(*tmp_info) - 1);
1274 xfs_da_log_buf(args->trans, new_blk->bp, 0, sizeof(*tmp_info) - 1);
1275 return(0);
1279 * Compare two intermediate nodes for "order".
1281 STATIC int
1282 xfs_da_node_order(xfs_dabuf_t *node1_bp, xfs_dabuf_t *node2_bp)
1284 xfs_da_intnode_t *node1, *node2;
1286 node1 = node1_bp->data;
1287 node2 = node2_bp->data;
1288 ASSERT((be16_to_cpu(node1->hdr.info.magic) == XFS_DA_NODE_MAGIC) &&
1289 (be16_to_cpu(node2->hdr.info.magic) == XFS_DA_NODE_MAGIC));
1290 if ((be16_to_cpu(node1->hdr.count) > 0) && (be16_to_cpu(node2->hdr.count) > 0) &&
1291 ((be32_to_cpu(node2->btree[0].hashval) <
1292 be32_to_cpu(node1->btree[0].hashval)) ||
1293 (be32_to_cpu(node2->btree[be16_to_cpu(node2->hdr.count)-1].hashval) <
1294 be32_to_cpu(node1->btree[be16_to_cpu(node1->hdr.count)-1].hashval)))) {
1295 return(1);
1297 return(0);
1301 * Pick up the last hashvalue from an intermediate node.
1303 STATIC uint
1304 xfs_da_node_lasthash(xfs_dabuf_t *bp, int *count)
1306 xfs_da_intnode_t *node;
1308 node = bp->data;
1309 ASSERT(be16_to_cpu(node->hdr.info.magic) == XFS_DA_NODE_MAGIC);
1310 if (count)
1311 *count = be16_to_cpu(node->hdr.count);
1312 if (!node->hdr.count)
1313 return(0);
1314 return be32_to_cpu(node->btree[be16_to_cpu(node->hdr.count)-1].hashval);
1318 * Unlink a block from a doubly linked list of blocks.
1320 STATIC int /* error */
1321 xfs_da_blk_unlink(xfs_da_state_t *state, xfs_da_state_blk_t *drop_blk,
1322 xfs_da_state_blk_t *save_blk)
1324 xfs_da_blkinfo_t *drop_info, *save_info, *tmp_info;
1325 xfs_da_args_t *args;
1326 xfs_dabuf_t *bp;
1327 int error;
1330 * Set up environment.
1332 args = state->args;
1333 ASSERT(args != NULL);
1334 save_info = save_blk->bp->data;
1335 drop_info = drop_blk->bp->data;
1336 ASSERT(save_blk->magic == XFS_DA_NODE_MAGIC ||
1337 save_blk->magic == XFS_DIR2_LEAFN_MAGIC ||
1338 save_blk->magic == XFS_ATTR_LEAF_MAGIC);
1339 ASSERT(save_blk->magic == be16_to_cpu(save_info->magic));
1340 ASSERT(drop_blk->magic == be16_to_cpu(drop_info->magic));
1341 ASSERT(save_blk->magic == drop_blk->magic);
1342 ASSERT((be32_to_cpu(save_info->forw) == drop_blk->blkno) ||
1343 (be32_to_cpu(save_info->back) == drop_blk->blkno));
1344 ASSERT((be32_to_cpu(drop_info->forw) == save_blk->blkno) ||
1345 (be32_to_cpu(drop_info->back) == save_blk->blkno));
1348 * Unlink the leaf block from the doubly linked chain of leaves.
1350 if (be32_to_cpu(save_info->back) == drop_blk->blkno) {
1351 save_info->back = drop_info->back;
1352 if (drop_info->back) {
1353 error = xfs_da_read_buf(args->trans, args->dp,
1354 be32_to_cpu(drop_info->back),
1355 -1, &bp, args->whichfork);
1356 if (error)
1357 return(error);
1358 ASSERT(bp != NULL);
1359 tmp_info = bp->data;
1360 ASSERT(tmp_info->magic == save_info->magic);
1361 ASSERT(be32_to_cpu(tmp_info->forw) == drop_blk->blkno);
1362 tmp_info->forw = cpu_to_be32(save_blk->blkno);
1363 xfs_da_log_buf(args->trans, bp, 0,
1364 sizeof(*tmp_info) - 1);
1365 xfs_da_buf_done(bp);
1367 } else {
1368 save_info->forw = drop_info->forw;
1369 if (drop_info->forw) {
1370 error = xfs_da_read_buf(args->trans, args->dp,
1371 be32_to_cpu(drop_info->forw),
1372 -1, &bp, args->whichfork);
1373 if (error)
1374 return(error);
1375 ASSERT(bp != NULL);
1376 tmp_info = bp->data;
1377 ASSERT(tmp_info->magic == save_info->magic);
1378 ASSERT(be32_to_cpu(tmp_info->back) == drop_blk->blkno);
1379 tmp_info->back = cpu_to_be32(save_blk->blkno);
1380 xfs_da_log_buf(args->trans, bp, 0,
1381 sizeof(*tmp_info) - 1);
1382 xfs_da_buf_done(bp);
1386 xfs_da_log_buf(args->trans, save_blk->bp, 0, sizeof(*save_info) - 1);
1387 return(0);
1391 * Move a path "forward" or "!forward" one block at the current level.
1393 * This routine will adjust a "path" to point to the next block
1394 * "forward" (higher hashvalues) or "!forward" (lower hashvals) in the
1395 * Btree, including updating pointers to the intermediate nodes between
1396 * the new bottom and the root.
1398 int /* error */
1399 xfs_da_path_shift(xfs_da_state_t *state, xfs_da_state_path_t *path,
1400 int forward, int release, int *result)
1402 xfs_da_state_blk_t *blk;
1403 xfs_da_blkinfo_t *info;
1404 xfs_da_intnode_t *node;
1405 xfs_da_args_t *args;
1406 xfs_dablk_t blkno=0;
1407 int level, error;
1410 * Roll up the Btree looking for the first block where our
1411 * current index is not at the edge of the block. Note that
1412 * we skip the bottom layer because we want the sibling block.
1414 args = state->args;
1415 ASSERT(args != NULL);
1416 ASSERT(path != NULL);
1417 ASSERT((path->active > 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1418 level = (path->active-1) - 1; /* skip bottom layer in path */
1419 for (blk = &path->blk[level]; level >= 0; blk--, level--) {
1420 ASSERT(blk->bp != NULL);
1421 node = blk->bp->data;
1422 ASSERT(be16_to_cpu(node->hdr.info.magic) == XFS_DA_NODE_MAGIC);
1423 if (forward && (blk->index < be16_to_cpu(node->hdr.count)-1)) {
1424 blk->index++;
1425 blkno = be32_to_cpu(node->btree[blk->index].before);
1426 break;
1427 } else if (!forward && (blk->index > 0)) {
1428 blk->index--;
1429 blkno = be32_to_cpu(node->btree[blk->index].before);
1430 break;
1433 if (level < 0) {
1434 *result = XFS_ERROR(ENOENT); /* we're out of our tree */
1435 ASSERT(args->oknoent);
1436 return(0);
1440 * Roll down the edge of the subtree until we reach the
1441 * same depth we were at originally.
1443 for (blk++, level++; level < path->active; blk++, level++) {
1445 * Release the old block.
1446 * (if it's dirty, trans won't actually let go)
1448 if (release)
1449 xfs_da_brelse(args->trans, blk->bp);
1452 * Read the next child block.
1454 blk->blkno = blkno;
1455 error = xfs_da_read_buf(args->trans, args->dp, blkno, -1,
1456 &blk->bp, args->whichfork);
1457 if (error)
1458 return(error);
1459 ASSERT(blk->bp != NULL);
1460 info = blk->bp->data;
1461 ASSERT(be16_to_cpu(info->magic) == XFS_DA_NODE_MAGIC ||
1462 be16_to_cpu(info->magic) == XFS_DIR2_LEAFN_MAGIC ||
1463 be16_to_cpu(info->magic) == XFS_ATTR_LEAF_MAGIC);
1464 blk->magic = be16_to_cpu(info->magic);
1465 if (blk->magic == XFS_DA_NODE_MAGIC) {
1466 node = (xfs_da_intnode_t *)info;
1467 blk->hashval = be32_to_cpu(node->btree[be16_to_cpu(node->hdr.count)-1].hashval);
1468 if (forward)
1469 blk->index = 0;
1470 else
1471 blk->index = be16_to_cpu(node->hdr.count)-1;
1472 blkno = be32_to_cpu(node->btree[blk->index].before);
1473 } else {
1474 ASSERT(level == path->active-1);
1475 blk->index = 0;
1476 switch(blk->magic) {
1477 case XFS_ATTR_LEAF_MAGIC:
1478 blk->hashval = xfs_attr_leaf_lasthash(blk->bp,
1479 NULL);
1480 break;
1481 case XFS_DIR2_LEAFN_MAGIC:
1482 blk->hashval = xfs_dir2_leafn_lasthash(blk->bp,
1483 NULL);
1484 break;
1485 default:
1486 ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC ||
1487 blk->magic == XFS_DIR2_LEAFN_MAGIC);
1488 break;
1492 *result = 0;
1493 return(0);
1497 /*========================================================================
1498 * Utility routines.
1499 *========================================================================*/
1502 * Implement a simple hash on a character string.
1503 * Rotate the hash value by 7 bits, then XOR each character in.
1504 * This is implemented with some source-level loop unrolling.
1506 xfs_dahash_t
1507 xfs_da_hashname(const uchar_t *name, int namelen)
1509 xfs_dahash_t hash;
1512 * Do four characters at a time as long as we can.
1514 for (hash = 0; namelen >= 4; namelen -= 4, name += 4)
1515 hash = (name[0] << 21) ^ (name[1] << 14) ^ (name[2] << 7) ^
1516 (name[3] << 0) ^ rol32(hash, 7 * 4);
1519 * Now do the rest of the characters.
1521 switch (namelen) {
1522 case 3:
1523 return (name[0] << 14) ^ (name[1] << 7) ^ (name[2] << 0) ^
1524 rol32(hash, 7 * 3);
1525 case 2:
1526 return (name[0] << 7) ^ (name[1] << 0) ^ rol32(hash, 7 * 2);
1527 case 1:
1528 return (name[0] << 0) ^ rol32(hash, 7 * 1);
1529 default: /* case 0: */
1530 return hash;
1535 * Add a block to the btree ahead of the file.
1536 * Return the new block number to the caller.
1539 xfs_da_grow_inode(xfs_da_args_t *args, xfs_dablk_t *new_blkno)
1541 xfs_fileoff_t bno, b;
1542 xfs_bmbt_irec_t map;
1543 xfs_bmbt_irec_t *mapp;
1544 xfs_inode_t *dp;
1545 int nmap, error, w, count, c, got, i, mapi;
1546 xfs_trans_t *tp;
1547 xfs_mount_t *mp;
1549 dp = args->dp;
1550 mp = dp->i_mount;
1551 w = args->whichfork;
1552 tp = args->trans;
1554 * For new directories adjust the file offset and block count.
1556 if (w == XFS_DATA_FORK) {
1557 bno = mp->m_dirleafblk;
1558 count = mp->m_dirblkfsbs;
1559 } else {
1560 bno = 0;
1561 count = 1;
1564 * Find a spot in the file space to put the new block.
1566 if ((error = xfs_bmap_first_unused(tp, dp, count, &bno, w)))
1567 return error;
1568 if (w == XFS_DATA_FORK)
1569 ASSERT(bno >= mp->m_dirleafblk && bno < mp->m_dirfreeblk);
1571 * Try mapping it in one filesystem block.
1573 nmap = 1;
1574 ASSERT(args->firstblock != NULL);
1575 if ((error = xfs_bmapi(tp, dp, bno, count,
1576 XFS_BMAPI_AFLAG(w)|XFS_BMAPI_WRITE|XFS_BMAPI_METADATA|
1577 XFS_BMAPI_CONTIG,
1578 args->firstblock, args->total, &map, &nmap,
1579 args->flist, NULL))) {
1580 return error;
1582 ASSERT(nmap <= 1);
1583 if (nmap == 1) {
1584 mapp = &map;
1585 mapi = 1;
1588 * If we didn't get it and the block might work if fragmented,
1589 * try without the CONTIG flag. Loop until we get it all.
1591 else if (nmap == 0 && count > 1) {
1592 mapp = kmem_alloc(sizeof(*mapp) * count, KM_SLEEP);
1593 for (b = bno, mapi = 0; b < bno + count; ) {
1594 nmap = MIN(XFS_BMAP_MAX_NMAP, count);
1595 c = (int)(bno + count - b);
1596 if ((error = xfs_bmapi(tp, dp, b, c,
1597 XFS_BMAPI_AFLAG(w)|XFS_BMAPI_WRITE|
1598 XFS_BMAPI_METADATA,
1599 args->firstblock, args->total,
1600 &mapp[mapi], &nmap, args->flist,
1601 NULL))) {
1602 kmem_free(mapp, sizeof(*mapp) * count);
1603 return error;
1605 if (nmap < 1)
1606 break;
1607 mapi += nmap;
1608 b = mapp[mapi - 1].br_startoff +
1609 mapp[mapi - 1].br_blockcount;
1611 } else {
1612 mapi = 0;
1613 mapp = NULL;
1616 * Count the blocks we got, make sure it matches the total.
1618 for (i = 0, got = 0; i < mapi; i++)
1619 got += mapp[i].br_blockcount;
1620 if (got != count || mapp[0].br_startoff != bno ||
1621 mapp[mapi - 1].br_startoff + mapp[mapi - 1].br_blockcount !=
1622 bno + count) {
1623 if (mapp != &map)
1624 kmem_free(mapp, sizeof(*mapp) * count);
1625 return XFS_ERROR(ENOSPC);
1627 if (mapp != &map)
1628 kmem_free(mapp, sizeof(*mapp) * count);
1629 *new_blkno = (xfs_dablk_t)bno;
1630 return 0;
1634 * Ick. We need to always be able to remove a btree block, even
1635 * if there's no space reservation because the filesystem is full.
1636 * This is called if xfs_bunmapi on a btree block fails due to ENOSPC.
1637 * It swaps the target block with the last block in the file. The
1638 * last block in the file can always be removed since it can't cause
1639 * a bmap btree split to do that.
1641 STATIC int
1642 xfs_da_swap_lastblock(xfs_da_args_t *args, xfs_dablk_t *dead_blknop,
1643 xfs_dabuf_t **dead_bufp)
1645 xfs_dablk_t dead_blkno, last_blkno, sib_blkno, par_blkno;
1646 xfs_dabuf_t *dead_buf, *last_buf, *sib_buf, *par_buf;
1647 xfs_fileoff_t lastoff;
1648 xfs_inode_t *ip;
1649 xfs_trans_t *tp;
1650 xfs_mount_t *mp;
1651 int error, w, entno, level, dead_level;
1652 xfs_da_blkinfo_t *dead_info, *sib_info;
1653 xfs_da_intnode_t *par_node, *dead_node;
1654 xfs_dir2_leaf_t *dead_leaf2;
1655 xfs_dahash_t dead_hash;
1657 dead_buf = *dead_bufp;
1658 dead_blkno = *dead_blknop;
1659 tp = args->trans;
1660 ip = args->dp;
1661 w = args->whichfork;
1662 ASSERT(w == XFS_DATA_FORK);
1663 mp = ip->i_mount;
1664 lastoff = mp->m_dirfreeblk;
1665 error = xfs_bmap_last_before(tp, ip, &lastoff, w);
1666 if (error)
1667 return error;
1668 if (unlikely(lastoff == 0)) {
1669 XFS_ERROR_REPORT("xfs_da_swap_lastblock(1)", XFS_ERRLEVEL_LOW,
1670 mp);
1671 return XFS_ERROR(EFSCORRUPTED);
1674 * Read the last block in the btree space.
1676 last_blkno = (xfs_dablk_t)lastoff - mp->m_dirblkfsbs;
1677 if ((error = xfs_da_read_buf(tp, ip, last_blkno, -1, &last_buf, w)))
1678 return error;
1680 * Copy the last block into the dead buffer and log it.
1682 memcpy(dead_buf->data, last_buf->data, mp->m_dirblksize);
1683 xfs_da_log_buf(tp, dead_buf, 0, mp->m_dirblksize - 1);
1684 dead_info = dead_buf->data;
1686 * Get values from the moved block.
1688 if (be16_to_cpu(dead_info->magic) == XFS_DIR2_LEAFN_MAGIC) {
1689 dead_leaf2 = (xfs_dir2_leaf_t *)dead_info;
1690 dead_level = 0;
1691 dead_hash = be32_to_cpu(dead_leaf2->ents[be16_to_cpu(dead_leaf2->hdr.count) - 1].hashval);
1692 } else {
1693 ASSERT(be16_to_cpu(dead_info->magic) == XFS_DA_NODE_MAGIC);
1694 dead_node = (xfs_da_intnode_t *)dead_info;
1695 dead_level = be16_to_cpu(dead_node->hdr.level);
1696 dead_hash = be32_to_cpu(dead_node->btree[be16_to_cpu(dead_node->hdr.count) - 1].hashval);
1698 sib_buf = par_buf = NULL;
1700 * If the moved block has a left sibling, fix up the pointers.
1702 if ((sib_blkno = be32_to_cpu(dead_info->back))) {
1703 if ((error = xfs_da_read_buf(tp, ip, sib_blkno, -1, &sib_buf, w)))
1704 goto done;
1705 sib_info = sib_buf->data;
1706 if (unlikely(
1707 be32_to_cpu(sib_info->forw) != last_blkno ||
1708 sib_info->magic != dead_info->magic)) {
1709 XFS_ERROR_REPORT("xfs_da_swap_lastblock(2)",
1710 XFS_ERRLEVEL_LOW, mp);
1711 error = XFS_ERROR(EFSCORRUPTED);
1712 goto done;
1714 sib_info->forw = cpu_to_be32(dead_blkno);
1715 xfs_da_log_buf(tp, sib_buf,
1716 XFS_DA_LOGRANGE(sib_info, &sib_info->forw,
1717 sizeof(sib_info->forw)));
1718 xfs_da_buf_done(sib_buf);
1719 sib_buf = NULL;
1722 * If the moved block has a right sibling, fix up the pointers.
1724 if ((sib_blkno = be32_to_cpu(dead_info->forw))) {
1725 if ((error = xfs_da_read_buf(tp, ip, sib_blkno, -1, &sib_buf, w)))
1726 goto done;
1727 sib_info = sib_buf->data;
1728 if (unlikely(
1729 be32_to_cpu(sib_info->back) != last_blkno ||
1730 sib_info->magic != dead_info->magic)) {
1731 XFS_ERROR_REPORT("xfs_da_swap_lastblock(3)",
1732 XFS_ERRLEVEL_LOW, mp);
1733 error = XFS_ERROR(EFSCORRUPTED);
1734 goto done;
1736 sib_info->back = cpu_to_be32(dead_blkno);
1737 xfs_da_log_buf(tp, sib_buf,
1738 XFS_DA_LOGRANGE(sib_info, &sib_info->back,
1739 sizeof(sib_info->back)));
1740 xfs_da_buf_done(sib_buf);
1741 sib_buf = NULL;
1743 par_blkno = mp->m_dirleafblk;
1744 level = -1;
1746 * Walk down the tree looking for the parent of the moved block.
1748 for (;;) {
1749 if ((error = xfs_da_read_buf(tp, ip, par_blkno, -1, &par_buf, w)))
1750 goto done;
1751 par_node = par_buf->data;
1752 if (unlikely(
1753 be16_to_cpu(par_node->hdr.info.magic) != XFS_DA_NODE_MAGIC ||
1754 (level >= 0 && level != be16_to_cpu(par_node->hdr.level) + 1))) {
1755 XFS_ERROR_REPORT("xfs_da_swap_lastblock(4)",
1756 XFS_ERRLEVEL_LOW, mp);
1757 error = XFS_ERROR(EFSCORRUPTED);
1758 goto done;
1760 level = be16_to_cpu(par_node->hdr.level);
1761 for (entno = 0;
1762 entno < be16_to_cpu(par_node->hdr.count) &&
1763 be32_to_cpu(par_node->btree[entno].hashval) < dead_hash;
1764 entno++)
1765 continue;
1766 if (unlikely(entno == be16_to_cpu(par_node->hdr.count))) {
1767 XFS_ERROR_REPORT("xfs_da_swap_lastblock(5)",
1768 XFS_ERRLEVEL_LOW, mp);
1769 error = XFS_ERROR(EFSCORRUPTED);
1770 goto done;
1772 par_blkno = be32_to_cpu(par_node->btree[entno].before);
1773 if (level == dead_level + 1)
1774 break;
1775 xfs_da_brelse(tp, par_buf);
1776 par_buf = NULL;
1779 * We're in the right parent block.
1780 * Look for the right entry.
1782 for (;;) {
1783 for (;
1784 entno < be16_to_cpu(par_node->hdr.count) &&
1785 be32_to_cpu(par_node->btree[entno].before) != last_blkno;
1786 entno++)
1787 continue;
1788 if (entno < be16_to_cpu(par_node->hdr.count))
1789 break;
1790 par_blkno = be32_to_cpu(par_node->hdr.info.forw);
1791 xfs_da_brelse(tp, par_buf);
1792 par_buf = NULL;
1793 if (unlikely(par_blkno == 0)) {
1794 XFS_ERROR_REPORT("xfs_da_swap_lastblock(6)",
1795 XFS_ERRLEVEL_LOW, mp);
1796 error = XFS_ERROR(EFSCORRUPTED);
1797 goto done;
1799 if ((error = xfs_da_read_buf(tp, ip, par_blkno, -1, &par_buf, w)))
1800 goto done;
1801 par_node = par_buf->data;
1802 if (unlikely(
1803 be16_to_cpu(par_node->hdr.level) != level ||
1804 be16_to_cpu(par_node->hdr.info.magic) != XFS_DA_NODE_MAGIC)) {
1805 XFS_ERROR_REPORT("xfs_da_swap_lastblock(7)",
1806 XFS_ERRLEVEL_LOW, mp);
1807 error = XFS_ERROR(EFSCORRUPTED);
1808 goto done;
1810 entno = 0;
1813 * Update the parent entry pointing to the moved block.
1815 par_node->btree[entno].before = cpu_to_be32(dead_blkno);
1816 xfs_da_log_buf(tp, par_buf,
1817 XFS_DA_LOGRANGE(par_node, &par_node->btree[entno].before,
1818 sizeof(par_node->btree[entno].before)));
1819 xfs_da_buf_done(par_buf);
1820 xfs_da_buf_done(dead_buf);
1821 *dead_blknop = last_blkno;
1822 *dead_bufp = last_buf;
1823 return 0;
1824 done:
1825 if (par_buf)
1826 xfs_da_brelse(tp, par_buf);
1827 if (sib_buf)
1828 xfs_da_brelse(tp, sib_buf);
1829 xfs_da_brelse(tp, last_buf);
1830 return error;
1834 * Remove a btree block from a directory or attribute.
1837 xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno,
1838 xfs_dabuf_t *dead_buf)
1840 xfs_inode_t *dp;
1841 int done, error, w, count;
1842 xfs_trans_t *tp;
1843 xfs_mount_t *mp;
1845 dp = args->dp;
1846 w = args->whichfork;
1847 tp = args->trans;
1848 mp = dp->i_mount;
1849 if (w == XFS_DATA_FORK)
1850 count = mp->m_dirblkfsbs;
1851 else
1852 count = 1;
1853 for (;;) {
1855 * Remove extents. If we get ENOSPC for a dir we have to move
1856 * the last block to the place we want to kill.
1858 if ((error = xfs_bunmapi(tp, dp, dead_blkno, count,
1859 XFS_BMAPI_AFLAG(w)|XFS_BMAPI_METADATA,
1860 0, args->firstblock, args->flist, NULL,
1861 &done)) == ENOSPC) {
1862 if (w != XFS_DATA_FORK)
1863 break;
1864 if ((error = xfs_da_swap_lastblock(args, &dead_blkno,
1865 &dead_buf)))
1866 break;
1867 } else {
1868 break;
1871 xfs_da_binval(tp, dead_buf);
1872 return error;
1876 * See if the mapping(s) for this btree block are valid, i.e.
1877 * don't contain holes, are logically contiguous, and cover the whole range.
1879 STATIC int
1880 xfs_da_map_covers_blocks(
1881 int nmap,
1882 xfs_bmbt_irec_t *mapp,
1883 xfs_dablk_t bno,
1884 int count)
1886 int i;
1887 xfs_fileoff_t off;
1889 for (i = 0, off = bno; i < nmap; i++) {
1890 if (mapp[i].br_startblock == HOLESTARTBLOCK ||
1891 mapp[i].br_startblock == DELAYSTARTBLOCK) {
1892 return 0;
1894 if (off != mapp[i].br_startoff) {
1895 return 0;
1897 off += mapp[i].br_blockcount;
1899 return off == bno + count;
1903 * Make a dabuf.
1904 * Used for get_buf, read_buf, read_bufr, and reada_buf.
1906 STATIC int
1907 xfs_da_do_buf(
1908 xfs_trans_t *trans,
1909 xfs_inode_t *dp,
1910 xfs_dablk_t bno,
1911 xfs_daddr_t *mappedbnop,
1912 xfs_dabuf_t **bpp,
1913 int whichfork,
1914 int caller,
1915 inst_t *ra)
1917 xfs_buf_t *bp = NULL;
1918 xfs_buf_t **bplist;
1919 int error=0;
1920 int i;
1921 xfs_bmbt_irec_t map;
1922 xfs_bmbt_irec_t *mapp;
1923 xfs_daddr_t mappedbno;
1924 xfs_mount_t *mp;
1925 int nbplist=0;
1926 int nfsb;
1927 int nmap;
1928 xfs_dabuf_t *rbp;
1930 mp = dp->i_mount;
1931 nfsb = (whichfork == XFS_DATA_FORK) ? mp->m_dirblkfsbs : 1;
1932 mappedbno = *mappedbnop;
1934 * Caller doesn't have a mapping. -2 means don't complain
1935 * if we land in a hole.
1937 if (mappedbno == -1 || mappedbno == -2) {
1939 * Optimize the one-block case.
1941 if (nfsb == 1) {
1942 xfs_fsblock_t fsb;
1944 if ((error =
1945 xfs_bmapi_single(trans, dp, whichfork, &fsb,
1946 (xfs_fileoff_t)bno))) {
1947 return error;
1949 mapp = &map;
1950 if (fsb == NULLFSBLOCK) {
1951 nmap = 0;
1952 } else {
1953 map.br_startblock = fsb;
1954 map.br_startoff = (xfs_fileoff_t)bno;
1955 map.br_blockcount = 1;
1956 nmap = 1;
1958 } else {
1959 mapp = kmem_alloc(sizeof(*mapp) * nfsb, KM_SLEEP);
1960 nmap = nfsb;
1961 if ((error = xfs_bmapi(trans, dp, (xfs_fileoff_t)bno,
1962 nfsb,
1963 XFS_BMAPI_METADATA |
1964 XFS_BMAPI_AFLAG(whichfork),
1965 NULL, 0, mapp, &nmap, NULL, NULL)))
1966 goto exit0;
1968 } else {
1969 map.br_startblock = XFS_DADDR_TO_FSB(mp, mappedbno);
1970 map.br_startoff = (xfs_fileoff_t)bno;
1971 map.br_blockcount = nfsb;
1972 mapp = &map;
1973 nmap = 1;
1975 if (!xfs_da_map_covers_blocks(nmap, mapp, bno, nfsb)) {
1976 error = mappedbno == -2 ? 0 : XFS_ERROR(EFSCORRUPTED);
1977 if (unlikely(error == EFSCORRUPTED)) {
1978 if (xfs_error_level >= XFS_ERRLEVEL_LOW) {
1979 int i;
1980 cmn_err(CE_ALERT, "xfs_da_do_buf: bno %lld\n",
1981 (long long)bno);
1982 cmn_err(CE_ALERT, "dir: inode %lld\n",
1983 (long long)dp->i_ino);
1984 for (i = 0; i < nmap; i++) {
1985 cmn_err(CE_ALERT,
1986 "[%02d] br_startoff %lld br_startblock %lld br_blockcount %lld br_state %d\n",
1988 (long long)mapp[i].br_startoff,
1989 (long long)mapp[i].br_startblock,
1990 (long long)mapp[i].br_blockcount,
1991 mapp[i].br_state);
1994 XFS_ERROR_REPORT("xfs_da_do_buf(1)",
1995 XFS_ERRLEVEL_LOW, mp);
1997 goto exit0;
1999 if (caller != 3 && nmap > 1) {
2000 bplist = kmem_alloc(sizeof(*bplist) * nmap, KM_SLEEP);
2001 nbplist = 0;
2002 } else
2003 bplist = NULL;
2005 * Turn the mapping(s) into buffer(s).
2007 for (i = 0; i < nmap; i++) {
2008 int nmapped;
2010 mappedbno = XFS_FSB_TO_DADDR(mp, mapp[i].br_startblock);
2011 if (i == 0)
2012 *mappedbnop = mappedbno;
2013 nmapped = (int)XFS_FSB_TO_BB(mp, mapp[i].br_blockcount);
2014 switch (caller) {
2015 case 0:
2016 bp = xfs_trans_get_buf(trans, mp->m_ddev_targp,
2017 mappedbno, nmapped, 0);
2018 error = bp ? XFS_BUF_GETERROR(bp) : XFS_ERROR(EIO);
2019 break;
2020 case 1:
2021 case 2:
2022 bp = NULL;
2023 error = xfs_trans_read_buf(mp, trans, mp->m_ddev_targp,
2024 mappedbno, nmapped, 0, &bp);
2025 break;
2026 case 3:
2027 xfs_baread(mp->m_ddev_targp, mappedbno, nmapped);
2028 error = 0;
2029 bp = NULL;
2030 break;
2032 if (error) {
2033 if (bp)
2034 xfs_trans_brelse(trans, bp);
2035 goto exit1;
2037 if (!bp)
2038 continue;
2039 if (caller == 1) {
2040 if (whichfork == XFS_ATTR_FORK) {
2041 XFS_BUF_SET_VTYPE_REF(bp, B_FS_ATTR_BTREE,
2042 XFS_ATTR_BTREE_REF);
2043 } else {
2044 XFS_BUF_SET_VTYPE_REF(bp, B_FS_DIR_BTREE,
2045 XFS_DIR_BTREE_REF);
2048 if (bplist) {
2049 bplist[nbplist++] = bp;
2053 * Build a dabuf structure.
2055 if (bplist) {
2056 rbp = xfs_da_buf_make(nbplist, bplist, ra);
2057 } else if (bp)
2058 rbp = xfs_da_buf_make(1, &bp, ra);
2059 else
2060 rbp = NULL;
2062 * For read_buf, check the magic number.
2064 if (caller == 1) {
2065 xfs_dir2_data_t *data;
2066 xfs_dir2_free_t *free;
2067 xfs_da_blkinfo_t *info;
2068 uint magic, magic1;
2070 info = rbp->data;
2071 data = rbp->data;
2072 free = rbp->data;
2073 magic = be16_to_cpu(info->magic);
2074 magic1 = be32_to_cpu(data->hdr.magic);
2075 if (unlikely(
2076 XFS_TEST_ERROR((magic != XFS_DA_NODE_MAGIC) &&
2077 (magic != XFS_ATTR_LEAF_MAGIC) &&
2078 (magic != XFS_DIR2_LEAF1_MAGIC) &&
2079 (magic != XFS_DIR2_LEAFN_MAGIC) &&
2080 (magic1 != XFS_DIR2_BLOCK_MAGIC) &&
2081 (magic1 != XFS_DIR2_DATA_MAGIC) &&
2082 (be32_to_cpu(free->hdr.magic) != XFS_DIR2_FREE_MAGIC),
2083 mp, XFS_ERRTAG_DA_READ_BUF,
2084 XFS_RANDOM_DA_READ_BUF))) {
2085 xfs_buftrace("DA READ ERROR", rbp->bps[0]);
2086 XFS_CORRUPTION_ERROR("xfs_da_do_buf(2)",
2087 XFS_ERRLEVEL_LOW, mp, info);
2088 error = XFS_ERROR(EFSCORRUPTED);
2089 xfs_da_brelse(trans, rbp);
2090 nbplist = 0;
2091 goto exit1;
2094 if (bplist) {
2095 kmem_free(bplist, sizeof(*bplist) * nmap);
2097 if (mapp != &map) {
2098 kmem_free(mapp, sizeof(*mapp) * nfsb);
2100 if (bpp)
2101 *bpp = rbp;
2102 return 0;
2103 exit1:
2104 if (bplist) {
2105 for (i = 0; i < nbplist; i++)
2106 xfs_trans_brelse(trans, bplist[i]);
2107 kmem_free(bplist, sizeof(*bplist) * nmap);
2109 exit0:
2110 if (mapp != &map)
2111 kmem_free(mapp, sizeof(*mapp) * nfsb);
2112 if (bpp)
2113 *bpp = NULL;
2114 return error;
2118 * Get a buffer for the dir/attr block.
2121 xfs_da_get_buf(
2122 xfs_trans_t *trans,
2123 xfs_inode_t *dp,
2124 xfs_dablk_t bno,
2125 xfs_daddr_t mappedbno,
2126 xfs_dabuf_t **bpp,
2127 int whichfork)
2129 return xfs_da_do_buf(trans, dp, bno, &mappedbno, bpp, whichfork, 0,
2130 (inst_t *)__return_address);
2134 * Get a buffer for the dir/attr block, fill in the contents.
2137 xfs_da_read_buf(
2138 xfs_trans_t *trans,
2139 xfs_inode_t *dp,
2140 xfs_dablk_t bno,
2141 xfs_daddr_t mappedbno,
2142 xfs_dabuf_t **bpp,
2143 int whichfork)
2145 return xfs_da_do_buf(trans, dp, bno, &mappedbno, bpp, whichfork, 1,
2146 (inst_t *)__return_address);
2150 * Readahead the dir/attr block.
2152 xfs_daddr_t
2153 xfs_da_reada_buf(
2154 xfs_trans_t *trans,
2155 xfs_inode_t *dp,
2156 xfs_dablk_t bno,
2157 int whichfork)
2159 xfs_daddr_t rval;
2161 rval = -1;
2162 if (xfs_da_do_buf(trans, dp, bno, &rval, NULL, whichfork, 3,
2163 (inst_t *)__return_address))
2164 return -1;
2165 else
2166 return rval;
2170 * Calculate the number of bits needed to hold i different values.
2172 uint
2173 xfs_da_log2_roundup(uint i)
2175 uint rval;
2177 for (rval = 0; rval < NBBY * sizeof(i); rval++) {
2178 if ((1 << rval) >= i)
2179 break;
2181 return(rval);
2184 kmem_zone_t *xfs_da_state_zone; /* anchor for state struct zone */
2185 kmem_zone_t *xfs_dabuf_zone; /* dabuf zone */
2188 * Allocate a dir-state structure.
2189 * We don't put them on the stack since they're large.
2191 xfs_da_state_t *
2192 xfs_da_state_alloc(void)
2194 return kmem_zone_zalloc(xfs_da_state_zone, KM_SLEEP);
2198 * Kill the altpath contents of a da-state structure.
2200 STATIC void
2201 xfs_da_state_kill_altpath(xfs_da_state_t *state)
2203 int i;
2205 for (i = 0; i < state->altpath.active; i++) {
2206 if (state->altpath.blk[i].bp) {
2207 if (state->altpath.blk[i].bp != state->path.blk[i].bp)
2208 xfs_da_buf_done(state->altpath.blk[i].bp);
2209 state->altpath.blk[i].bp = NULL;
2212 state->altpath.active = 0;
2216 * Free a da-state structure.
2218 void
2219 xfs_da_state_free(xfs_da_state_t *state)
2221 int i;
2223 xfs_da_state_kill_altpath(state);
2224 for (i = 0; i < state->path.active; i++) {
2225 if (state->path.blk[i].bp)
2226 xfs_da_buf_done(state->path.blk[i].bp);
2228 if (state->extravalid && state->extrablk.bp)
2229 xfs_da_buf_done(state->extrablk.bp);
2230 #ifdef DEBUG
2231 memset((char *)state, 0, sizeof(*state));
2232 #endif /* DEBUG */
2233 kmem_zone_free(xfs_da_state_zone, state);
2236 #ifdef XFS_DABUF_DEBUG
2237 xfs_dabuf_t *xfs_dabuf_global_list;
2238 lock_t xfs_dabuf_global_lock;
2239 #endif
2242 * Create a dabuf.
2244 /* ARGSUSED */
2245 STATIC xfs_dabuf_t *
2246 xfs_da_buf_make(int nbuf, xfs_buf_t **bps, inst_t *ra)
2248 xfs_buf_t *bp;
2249 xfs_dabuf_t *dabuf;
2250 int i;
2251 int off;
2253 if (nbuf == 1)
2254 dabuf = kmem_zone_alloc(xfs_dabuf_zone, KM_SLEEP);
2255 else
2256 dabuf = kmem_alloc(XFS_DA_BUF_SIZE(nbuf), KM_SLEEP);
2257 dabuf->dirty = 0;
2258 #ifdef XFS_DABUF_DEBUG
2259 dabuf->ra = ra;
2260 dabuf->target = XFS_BUF_TARGET(bps[0]);
2261 dabuf->blkno = XFS_BUF_ADDR(bps[0]);
2262 #endif
2263 if (nbuf == 1) {
2264 dabuf->nbuf = 1;
2265 bp = bps[0];
2266 dabuf->bbcount = (short)BTOBB(XFS_BUF_COUNT(bp));
2267 dabuf->data = XFS_BUF_PTR(bp);
2268 dabuf->bps[0] = bp;
2269 } else {
2270 dabuf->nbuf = nbuf;
2271 for (i = 0, dabuf->bbcount = 0; i < nbuf; i++) {
2272 dabuf->bps[i] = bp = bps[i];
2273 dabuf->bbcount += BTOBB(XFS_BUF_COUNT(bp));
2275 dabuf->data = kmem_alloc(BBTOB(dabuf->bbcount), KM_SLEEP);
2276 for (i = off = 0; i < nbuf; i++, off += XFS_BUF_COUNT(bp)) {
2277 bp = bps[i];
2278 memcpy((char *)dabuf->data + off, XFS_BUF_PTR(bp),
2279 XFS_BUF_COUNT(bp));
2282 #ifdef XFS_DABUF_DEBUG
2284 SPLDECL(s);
2285 xfs_dabuf_t *p;
2287 s = mutex_spinlock(&xfs_dabuf_global_lock);
2288 for (p = xfs_dabuf_global_list; p; p = p->next) {
2289 ASSERT(p->blkno != dabuf->blkno ||
2290 p->target != dabuf->target);
2292 dabuf->prev = NULL;
2293 if (xfs_dabuf_global_list)
2294 xfs_dabuf_global_list->prev = dabuf;
2295 dabuf->next = xfs_dabuf_global_list;
2296 xfs_dabuf_global_list = dabuf;
2297 mutex_spinunlock(&xfs_dabuf_global_lock, s);
2299 #endif
2300 return dabuf;
2304 * Un-dirty a dabuf.
2306 STATIC void
2307 xfs_da_buf_clean(xfs_dabuf_t *dabuf)
2309 xfs_buf_t *bp;
2310 int i;
2311 int off;
2313 if (dabuf->dirty) {
2314 ASSERT(dabuf->nbuf > 1);
2315 dabuf->dirty = 0;
2316 for (i = off = 0; i < dabuf->nbuf;
2317 i++, off += XFS_BUF_COUNT(bp)) {
2318 bp = dabuf->bps[i];
2319 memcpy(XFS_BUF_PTR(bp), (char *)dabuf->data + off,
2320 XFS_BUF_COUNT(bp));
2326 * Release a dabuf.
2328 void
2329 xfs_da_buf_done(xfs_dabuf_t *dabuf)
2331 ASSERT(dabuf);
2332 ASSERT(dabuf->nbuf && dabuf->data && dabuf->bbcount && dabuf->bps[0]);
2333 if (dabuf->dirty)
2334 xfs_da_buf_clean(dabuf);
2335 if (dabuf->nbuf > 1)
2336 kmem_free(dabuf->data, BBTOB(dabuf->bbcount));
2337 #ifdef XFS_DABUF_DEBUG
2339 SPLDECL(s);
2341 s = mutex_spinlock(&xfs_dabuf_global_lock);
2342 if (dabuf->prev)
2343 dabuf->prev->next = dabuf->next;
2344 else
2345 xfs_dabuf_global_list = dabuf->next;
2346 if (dabuf->next)
2347 dabuf->next->prev = dabuf->prev;
2348 mutex_spinunlock(&xfs_dabuf_global_lock, s);
2350 memset(dabuf, 0, XFS_DA_BUF_SIZE(dabuf->nbuf));
2351 #endif
2352 if (dabuf->nbuf == 1)
2353 kmem_zone_free(xfs_dabuf_zone, dabuf);
2354 else
2355 kmem_free(dabuf, XFS_DA_BUF_SIZE(dabuf->nbuf));
2359 * Log transaction from a dabuf.
2361 void
2362 xfs_da_log_buf(xfs_trans_t *tp, xfs_dabuf_t *dabuf, uint first, uint last)
2364 xfs_buf_t *bp;
2365 uint f;
2366 int i;
2367 uint l;
2368 int off;
2370 ASSERT(dabuf->nbuf && dabuf->data && dabuf->bbcount && dabuf->bps[0]);
2371 if (dabuf->nbuf == 1) {
2372 ASSERT(dabuf->data == (void *)XFS_BUF_PTR(dabuf->bps[0]));
2373 xfs_trans_log_buf(tp, dabuf->bps[0], first, last);
2374 return;
2376 dabuf->dirty = 1;
2377 ASSERT(first <= last);
2378 for (i = off = 0; i < dabuf->nbuf; i++, off += XFS_BUF_COUNT(bp)) {
2379 bp = dabuf->bps[i];
2380 f = off;
2381 l = f + XFS_BUF_COUNT(bp) - 1;
2382 if (f < first)
2383 f = first;
2384 if (l > last)
2385 l = last;
2386 if (f <= l)
2387 xfs_trans_log_buf(tp, bp, f - off, l - off);
2389 * B_DONE is set by xfs_trans_log buf.
2390 * If we don't set it on a new buffer (get not read)
2391 * then if we don't put anything in the buffer it won't
2392 * be set, and at commit it it released into the cache,
2393 * and then a read will fail.
2395 else if (!(XFS_BUF_ISDONE(bp)))
2396 XFS_BUF_DONE(bp);
2398 ASSERT(last < off);
2402 * Release dabuf from a transaction.
2403 * Have to free up the dabuf before the buffers are released,
2404 * since the synchronization on the dabuf is really the lock on the buffer.
2406 void
2407 xfs_da_brelse(xfs_trans_t *tp, xfs_dabuf_t *dabuf)
2409 xfs_buf_t *bp;
2410 xfs_buf_t **bplist;
2411 int i;
2412 int nbuf;
2414 ASSERT(dabuf->nbuf && dabuf->data && dabuf->bbcount && dabuf->bps[0]);
2415 if ((nbuf = dabuf->nbuf) == 1) {
2416 bplist = &bp;
2417 bp = dabuf->bps[0];
2418 } else {
2419 bplist = kmem_alloc(nbuf * sizeof(*bplist), KM_SLEEP);
2420 memcpy(bplist, dabuf->bps, nbuf * sizeof(*bplist));
2422 xfs_da_buf_done(dabuf);
2423 for (i = 0; i < nbuf; i++)
2424 xfs_trans_brelse(tp, bplist[i]);
2425 if (bplist != &bp)
2426 kmem_free(bplist, nbuf * sizeof(*bplist));
2430 * Invalidate dabuf from a transaction.
2432 void
2433 xfs_da_binval(xfs_trans_t *tp, xfs_dabuf_t *dabuf)
2435 xfs_buf_t *bp;
2436 xfs_buf_t **bplist;
2437 int i;
2438 int nbuf;
2440 ASSERT(dabuf->nbuf && dabuf->data && dabuf->bbcount && dabuf->bps[0]);
2441 if ((nbuf = dabuf->nbuf) == 1) {
2442 bplist = &bp;
2443 bp = dabuf->bps[0];
2444 } else {
2445 bplist = kmem_alloc(nbuf * sizeof(*bplist), KM_SLEEP);
2446 memcpy(bplist, dabuf->bps, nbuf * sizeof(*bplist));
2448 xfs_da_buf_done(dabuf);
2449 for (i = 0; i < nbuf; i++)
2450 xfs_trans_binval(tp, bplist[i]);
2451 if (bplist != &bp)
2452 kmem_free(bplist, nbuf * sizeof(*bplist));
2456 * Get the first daddr from a dabuf.
2458 xfs_daddr_t
2459 xfs_da_blkno(xfs_dabuf_t *dabuf)
2461 ASSERT(dabuf->nbuf);
2462 ASSERT(dabuf->data);
2463 return XFS_BUF_ADDR(dabuf->bps[0]);