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1 /*
2 * Copyright (c) 2000-2004 Silicon Graphics, Inc. All Rights Reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of version 2 of the GNU General Public License as
6 * published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it would be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
11 *
12 * Further, this software is distributed without any warranty that it is
13 * free of the rightful claim of any third person regarding infringement
14 * or the like. Any license provided herein, whether implied or
15 * otherwise, applies only to this software file. Patent licenses, if
16 * any, provided herein do not apply to combinations of this program with
17 * other software, or any other product whatsoever.
18 *
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write the Free Software Foundation, Inc., 59
21 * Temple Place - Suite 330, Boston MA 02111-1307, USA.
22 *
23 * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
24 * Mountain View, CA 94043, or:
25 *
26 * http://www.sgi.com
27 *
28 * For further information regarding this notice, see:
29 *
30 * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
31 */
32
33 #include "xfs.h"
34
35 #include "xfs_macros.h"
36 #include "xfs_types.h"
37 #include "xfs_inum.h"
38 #include "xfs_log.h"
39 #include "xfs_trans.h"
40 #include "xfs_sb.h"
41 #include "xfs_ag.h"
42 #include "xfs_dir.h"
43 #include "xfs_dir2.h"
44 #include "xfs_dmapi.h"
45 #include "xfs_mount.h"
46 #include "xfs_alloc_btree.h"
47 #include "xfs_bmap_btree.h"
48 #include "xfs_ialloc_btree.h"
49 #include "xfs_alloc.h"
50 #include "xfs_btree.h"
51 #include "xfs_attr_sf.h"
52 #include "xfs_dir_sf.h"
53 #include "xfs_dir2_sf.h"
54 #include "xfs_dinode.h"
55 #include "xfs_inode_item.h"
56 #include "xfs_inode.h"
57 #include "xfs_bmap.h"
58 #include "xfs_da_btree.h"
59 #include "xfs_attr.h"
60 #include "xfs_attr_leaf.h"
61 #include "xfs_dir_leaf.h"
62 #include "xfs_dir2_data.h"
63 #include "xfs_dir2_leaf.h"
64 #include "xfs_dir2_block.h"
65 #include "xfs_dir2_node.h"
66 #include "xfs_error.h"
67 #include "xfs_bit.h"
68
69 /*
70 * xfs_da_btree.c
71 *
72 * Routines to implement directories as Btrees of hashed names.
73 */
74
75 /*========================================================================
76 * Function prototypes for the kernel.
77 *========================================================================*/
78
79 /*
80 * Routines used for growing the Btree.
81 */
82 STATIC int xfs_da_root_split(xfs_da_state_t *state,
83 xfs_da_state_blk_t *existing_root,
84 xfs_da_state_blk_t *new_child);
85 STATIC int xfs_da_node_split(xfs_da_state_t *state,
86 xfs_da_state_blk_t *existing_blk,
87 xfs_da_state_blk_t *split_blk,
88 xfs_da_state_blk_t *blk_to_add,
89 int treelevel,
90 int *result);
91 STATIC void xfs_da_node_rebalance(xfs_da_state_t *state,
92 xfs_da_state_blk_t *node_blk_1,
93 xfs_da_state_blk_t *node_blk_2);
94 STATIC void xfs_da_node_add(xfs_da_state_t *state,
95 xfs_da_state_blk_t *old_node_blk,
96 xfs_da_state_blk_t *new_node_blk);
97
98 /*
99 * Routines used for shrinking the Btree.
100 */
101 STATIC int xfs_da_root_join(xfs_da_state_t *state,
102 xfs_da_state_blk_t *root_blk);
103 STATIC int xfs_da_node_toosmall(xfs_da_state_t *state, int *retval);
104 STATIC void xfs_da_node_remove(xfs_da_state_t *state,
105 xfs_da_state_blk_t *drop_blk);
106 STATIC void xfs_da_node_unbalance(xfs_da_state_t *state,
107 xfs_da_state_blk_t *src_node_blk,
108 xfs_da_state_blk_t *dst_node_blk);
109
110 /*
111 * Utility routines.
112 */
113 STATIC uint xfs_da_node_lasthash(xfs_dabuf_t *bp, int *count);
114 STATIC int xfs_da_node_order(xfs_dabuf_t *node1_bp, xfs_dabuf_t *node2_bp);
115 STATIC xfs_dabuf_t *xfs_da_buf_make(int nbuf, xfs_buf_t **bps, inst_t *ra);
116
117
118 /*========================================================================
119 * Routines used for growing the Btree.
120 *========================================================================*/
121
122 /*
123 * Create the initial contents of an intermediate node.
124 */
125 int
126 xfs_da_node_create(xfs_da_args_t *args, xfs_dablk_t blkno, int level,
127 xfs_dabuf_t **bpp, int whichfork)
128 {
129 xfs_da_intnode_t *node;
130 xfs_dabuf_t *bp;
131 int error;
132 xfs_trans_t *tp;
133
134 tp = args->trans;
135 error = xfs_da_get_buf(tp, args->dp, blkno, -1, &bp, whichfork);
136 if (error)
137 return(error);
138 ASSERT(bp != NULL);
139 node = bp->data;
140 node->hdr.info.forw = 0;
141 node->hdr.info.back = 0;
142 INT_SET(node->hdr.info.magic, ARCH_CONVERT, XFS_DA_NODE_MAGIC);
143 node->hdr.info.pad = 0;
144 node->hdr.count = 0;
145 INT_SET(node->hdr.level, ARCH_CONVERT, level);
146
147 xfs_da_log_buf(tp, bp,
148 XFS_DA_LOGRANGE(node, &node->hdr, sizeof(node->hdr)));
149
150 *bpp = bp;
151 return(0);
152 }
153
154 /*
155 * Split a leaf node, rebalance, then possibly split
156 * intermediate nodes, rebalance, etc.
157 */
158 int /* error */
159 xfs_da_split(xfs_da_state_t *state)
160 {
161 xfs_da_state_blk_t *oldblk, *newblk, *addblk;
162 xfs_da_intnode_t *node;
163 xfs_dabuf_t *bp;
164 int max, action, error, i;
165
166 /*
167 * Walk back up the tree splitting/inserting/adjusting as necessary.
168 * If we need to insert and there isn't room, split the node, then
169 * decide which fragment to insert the new block from below into.
170 * Note that we may split the root this way, but we need more fixup.
171 */
172 max = state->path.active - 1;
173 ASSERT((max >= 0) && (max < XFS_DA_NODE_MAXDEPTH));
174 ASSERT(state->path.blk[max].magic == XFS_ATTR_LEAF_MAGIC ||
175 state->path.blk[max].magic == XFS_DIRX_LEAF_MAGIC(state->mp));
176
177 addblk = &state->path.blk[max]; /* initial dummy value */
178 for (i = max; (i >= 0) && addblk; state->path.active--, i--) {
179 oldblk = &state->path.blk[i];
180 newblk = &state->altpath.blk[i];
181
182 /*
183 * If a leaf node then
184 * Allocate a new leaf node, then rebalance across them.
185 * else if an intermediate node then
186 * We split on the last layer, must we split the node?
187 */
188 switch (oldblk->magic) {
189 case XFS_ATTR_LEAF_MAGIC:
190 #ifndef __KERNEL__
191 return(ENOTTY);
192 #else
193 error = xfs_attr_leaf_split(state, oldblk, newblk);
194 if ((error != 0) && (error != ENOSPC)) {
195 return(error); /* GROT: attr is inconsistent */
196 }
197 if (!error) {
198 addblk = newblk;
199 break;
200 }
201 /*
202 * Entry wouldn't fit, split the leaf again.
203 */
204 state->extravalid = 1;
205 if (state->inleaf) {
206 state->extraafter = 0; /* before newblk */
207 error = xfs_attr_leaf_split(state, oldblk,
208 &state->extrablk);
209 } else {
210 state->extraafter = 1; /* after newblk */
211 error = xfs_attr_leaf_split(state, newblk,
212 &state->extrablk);
213 }
214 if (error)
215 return(error); /* GROT: attr inconsistent */
216 addblk = newblk;
217 break;
218 #endif
219 case XFS_DIR_LEAF_MAGIC:
220 ASSERT(XFS_DIR_IS_V1(state->mp));
221 error = xfs_dir_leaf_split(state, oldblk, newblk);
222 if ((error != 0) && (error != ENOSPC)) {
223 return(error); /* GROT: dir is inconsistent */
224 }
225 if (!error) {
226 addblk = newblk;
227 break;
228 }
229 /*
230 * Entry wouldn't fit, split the leaf again.
231 */
232 state->extravalid = 1;
233 if (state->inleaf) {
234 state->extraafter = 0; /* before newblk */
235 error = xfs_dir_leaf_split(state, oldblk,
236 &state->extrablk);
237 if (error)
238 return(error); /* GROT: dir incon. */
239 addblk = newblk;
240 } else {
241 state->extraafter = 1; /* after newblk */
242 error = xfs_dir_leaf_split(state, newblk,
243 &state->extrablk);
244 if (error)
245 return(error); /* GROT: dir incon. */
246 addblk = newblk;
247 }
248 break;
249 case XFS_DIR2_LEAFN_MAGIC:
250 ASSERT(XFS_DIR_IS_V2(state->mp));
251 error = xfs_dir2_leafn_split(state, oldblk, newblk);
252 if (error)
253 return error;
254 addblk = newblk;
255 break;
256 case XFS_DA_NODE_MAGIC:
257 error = xfs_da_node_split(state, oldblk, newblk, addblk,
258 max - i, &action);
259 xfs_da_buf_done(addblk->bp);
260 addblk->bp = NULL;
261 if (error)
262 return(error); /* GROT: dir is inconsistent */
263 /*
264 * Record the newly split block for the next time thru?
265 */
266 if (action)
267 addblk = newblk;
268 else
269 addblk = NULL;
270 break;
271 }
272
273 /*
274 * Update the btree to show the new hashval for this child.
275 */
276 xfs_da_fixhashpath(state, &state->path);
277 /*
278 * If we won't need this block again, it's getting dropped
279 * from the active path by the loop control, so we need
280 * to mark it done now.
281 */
282 if (i > 0 || !addblk)
283 xfs_da_buf_done(oldblk->bp);
284 }
285 if (!addblk)
286 return(0);
287
288 /*
289 * Split the root node.
290 */
291 ASSERT(state->path.active == 0);
292 oldblk = &state->path.blk[0];
293 error = xfs_da_root_split(state, oldblk, addblk);
294 if (error) {
295 xfs_da_buf_done(oldblk->bp);
296 xfs_da_buf_done(addblk->bp);
297 addblk->bp = NULL;
298 return(error); /* GROT: dir is inconsistent */
299 }
300
301 /*
302 * Update pointers to the node which used to be block 0 and
303 * just got bumped because of the addition of a new root node.
304 * There might be three blocks involved if a double split occurred,
305 * and the original block 0 could be at any position in the list.
306 */
307
308 node = oldblk->bp->data;
309 if (node->hdr.info.forw) {
310 if (INT_GET(node->hdr.info.forw, ARCH_CONVERT) == addblk->blkno) {
311 bp = addblk->bp;
312 } else {
313 ASSERT(state->extravalid);
314 bp = state->extrablk.bp;
315 }
316 node = bp->data;
317 INT_SET(node->hdr.info.back, ARCH_CONVERT, oldblk->blkno);
318 xfs_da_log_buf(state->args->trans, bp,
319 XFS_DA_LOGRANGE(node, &node->hdr.info,
320 sizeof(node->hdr.info)));
321 }
322 node = oldblk->bp->data;
323 if (INT_GET(node->hdr.info.back, ARCH_CONVERT)) {
324 if (INT_GET(node->hdr.info.back, ARCH_CONVERT) == addblk->blkno) {
325 bp = addblk->bp;
326 } else {
327 ASSERT(state->extravalid);
328 bp = state->extrablk.bp;
329 }
330 node = bp->data;
331 INT_SET(node->hdr.info.forw, ARCH_CONVERT, oldblk->blkno);
332 xfs_da_log_buf(state->args->trans, bp,
333 XFS_DA_LOGRANGE(node, &node->hdr.info,
334 sizeof(node->hdr.info)));
335 }
336 xfs_da_buf_done(oldblk->bp);
337 xfs_da_buf_done(addblk->bp);
338 addblk->bp = NULL;
339 return(0);
340 }
341
342 /*
343 * Split the root. We have to create a new root and point to the two
344 * parts (the split old root) that we just created. Copy block zero to
345 * the EOF, extending the inode in process.
346 */
347 STATIC int /* error */
348 xfs_da_root_split(xfs_da_state_t *state, xfs_da_state_blk_t *blk1,
349 xfs_da_state_blk_t *blk2)
350 {
351 xfs_da_intnode_t *node, *oldroot;
352 xfs_da_args_t *args;
353 xfs_dablk_t blkno;
354 xfs_dabuf_t *bp;
355 int error, size;
356 xfs_inode_t *dp;
357 xfs_trans_t *tp;
358 xfs_mount_t *mp;
359 xfs_dir2_leaf_t *leaf;
360
361 /*
362 * Copy the existing (incorrect) block from the root node position
363 * to a free space somewhere.
364 */
365 args = state->args;
366 ASSERT(args != NULL);
367 error = xfs_da_grow_inode(args, &blkno);
368 if (error)
369 return(error);
370 dp = args->dp;
371 tp = args->trans;
372 mp = state->mp;
373 error = xfs_da_get_buf(tp, dp, blkno, -1, &bp, args->whichfork);
374 if (error)
375 return(error);
376 ASSERT(bp != NULL);
377 node = bp->data;
378 oldroot = blk1->bp->data;
379 if (INT_GET(oldroot->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC) {
380 size = (int)((char *)&oldroot->btree[INT_GET(oldroot->hdr.count, ARCH_CONVERT)] -
381 (char *)oldroot);
382 } else {
383 ASSERT(XFS_DIR_IS_V2(mp));
384 ASSERT(INT_GET(oldroot->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
385 leaf = (xfs_dir2_leaf_t *)oldroot;
386 size = (int)((char *)&leaf->ents[INT_GET(leaf->hdr.count, ARCH_CONVERT)] -
387 (char *)leaf);
388 }
389 memcpy(node, oldroot, size);
390 xfs_da_log_buf(tp, bp, 0, size - 1);
391 xfs_da_buf_done(blk1->bp);
392 blk1->bp = bp;
393 blk1->blkno = blkno;
394
395 /*
396 * Set up the new root node.
397 */
398 error = xfs_da_node_create(args,
399 args->whichfork == XFS_DATA_FORK &&
400 XFS_DIR_IS_V2(mp) ? mp->m_dirleafblk : 0,
401 INT_GET(node->hdr.level, ARCH_CONVERT) + 1, &bp, args->whichfork);
402 if (error)
403 return(error);
404 node = bp->data;
405 INT_SET(node->btree[0].hashval, ARCH_CONVERT, blk1->hashval);
406 INT_SET(node->btree[0].before, ARCH_CONVERT, blk1->blkno);
407 INT_SET(node->btree[1].hashval, ARCH_CONVERT, blk2->hashval);
408 INT_SET(node->btree[1].before, ARCH_CONVERT, blk2->blkno);
409 INT_SET(node->hdr.count, ARCH_CONVERT, 2);
410
411 #ifdef DEBUG
412 if (INT_GET(oldroot->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC) {
413 ASSERT(blk1->blkno >= mp->m_dirleafblk &&
414 blk1->blkno < mp->m_dirfreeblk);
415 ASSERT(blk2->blkno >= mp->m_dirleafblk &&
416 blk2->blkno < mp->m_dirfreeblk);
417 }
418 #endif
419
420 /* Header is already logged by xfs_da_node_create */
421 xfs_da_log_buf(tp, bp,
422 XFS_DA_LOGRANGE(node, node->btree,
423 sizeof(xfs_da_node_entry_t) * 2));
424 xfs_da_buf_done(bp);
425
426 return(0);
427 }
428
429 /*
430 * Split the node, rebalance, then add the new entry.
431 */
432 STATIC int /* error */
433 xfs_da_node_split(xfs_da_state_t *state, xfs_da_state_blk_t *oldblk,
434 xfs_da_state_blk_t *newblk,
435 xfs_da_state_blk_t *addblk,
436 int treelevel, int *result)
437 {
438 xfs_da_intnode_t *node;
439 xfs_dablk_t blkno;
440 int newcount, error;
441 int useextra;
442
443 node = oldblk->bp->data;
444 ASSERT(INT_GET(node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
445
446 /*
447 * With V2 the extra block is data or freespace.
448 */
449 useextra = state->extravalid && XFS_DIR_IS_V1(state->mp);
450 newcount = 1 + useextra;
451 /*
452 * Do we have to split the node?
453 */
454 if ((INT_GET(node->hdr.count, ARCH_CONVERT) + newcount) > state->node_ents) {
455 /*
456 * Allocate a new node, add to the doubly linked chain of
457 * nodes, then move some of our excess entries into it.
458 */
459 error = xfs_da_grow_inode(state->args, &blkno);
460 if (error)
461 return(error); /* GROT: dir is inconsistent */
462
463 error = xfs_da_node_create(state->args, blkno, treelevel,
464 &newblk->bp, state->args->whichfork);
465 if (error)
466 return(error); /* GROT: dir is inconsistent */
467 newblk->blkno = blkno;
468 newblk->magic = XFS_DA_NODE_MAGIC;
469 xfs_da_node_rebalance(state, oldblk, newblk);
470 error = xfs_da_blk_link(state, oldblk, newblk);
471 if (error)
472 return(error);
473 *result = 1;
474 } else {
475 *result = 0;
476 }
477
478 /*
479 * Insert the new entry(s) into the correct block
480 * (updating last hashval in the process).
481 *
482 * xfs_da_node_add() inserts BEFORE the given index,
483 * and as a result of using node_lookup_int() we always
484 * point to a valid entry (not after one), but a split
485 * operation always results in a new block whose hashvals
486 * FOLLOW the current block.
487 *
488 * If we had double-split op below us, then add the extra block too.
489 */
490 node = oldblk->bp->data;
491 if (oldblk->index <= INT_GET(node->hdr.count, ARCH_CONVERT)) {
492 oldblk->index++;
493 xfs_da_node_add(state, oldblk, addblk);
494 if (useextra) {
495 if (state->extraafter)
496 oldblk->index++;
497 xfs_da_node_add(state, oldblk, &state->extrablk);
498 state->extravalid = 0;
499 }
500 } else {
501 newblk->index++;
502 xfs_da_node_add(state, newblk, addblk);
503 if (useextra) {
504 if (state->extraafter)
505 newblk->index++;
506 xfs_da_node_add(state, newblk, &state->extrablk);
507 state->extravalid = 0;
508 }
509 }
510
511 return(0);
512 }
513
514 /*
515 * Balance the btree elements between two intermediate nodes,
516 * usually one full and one empty.
517 *
518 * NOTE: if blk2 is empty, then it will get the upper half of blk1.
519 */
520 STATIC void
521 xfs_da_node_rebalance(xfs_da_state_t *state, xfs_da_state_blk_t *blk1,
522 xfs_da_state_blk_t *blk2)
523 {
524 xfs_da_intnode_t *node1, *node2, *tmpnode;
525 xfs_da_node_entry_t *btree_s, *btree_d;
526 int count, tmp;
527 xfs_trans_t *tp;
528
529 node1 = blk1->bp->data;
530 node2 = blk2->bp->data;
531 /*
532 * Figure out how many entries need to move, and in which direction.
533 * Swap the nodes around if that makes it simpler.
534 */
535 if ((INT_GET(node1->hdr.count, ARCH_CONVERT) > 0) && (INT_GET(node2->hdr.count, ARCH_CONVERT) > 0) &&
536 ((INT_GET(node2->btree[ 0 ].hashval, ARCH_CONVERT) < INT_GET(node1->btree[ 0 ].hashval, ARCH_CONVERT)) ||
537 (INT_GET(node2->btree[ INT_GET(node2->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT) <
538 INT_GET(node1->btree[ INT_GET(node1->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT)))) {
539 tmpnode = node1;
540 node1 = node2;
541 node2 = tmpnode;
542 }
543 ASSERT(INT_GET(node1->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
544 ASSERT(INT_GET(node2->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
545 count = (INT_GET(node1->hdr.count, ARCH_CONVERT) - INT_GET(node2->hdr.count, ARCH_CONVERT)) / 2;
546 if (count == 0)
547 return;
548 tp = state->args->trans;
549 /*
550 * Two cases: high-to-low and low-to-high.
551 */
552 if (count > 0) {
553 /*
554 * Move elements in node2 up to make a hole.
555 */
556 if ((tmp = INT_GET(node2->hdr.count, ARCH_CONVERT)) > 0) {
557 tmp *= (uint)sizeof(xfs_da_node_entry_t);
558 btree_s = &node2->btree[0];
559 btree_d = &node2->btree[count];
560 memmove(btree_d, btree_s, tmp);
561 }
562
563 /*
564 * Move the req'd B-tree elements from high in node1 to
565 * low in node2.
566 */
567 INT_MOD(node2->hdr.count, ARCH_CONVERT, count);
568 tmp = count * (uint)sizeof(xfs_da_node_entry_t);
569 btree_s = &node1->btree[INT_GET(node1->hdr.count, ARCH_CONVERT) - count];
570 btree_d = &node2->btree[0];
571 memcpy(btree_d, btree_s, tmp);
572 INT_MOD(node1->hdr.count, ARCH_CONVERT, -(count));
573
574 } else {
575 /*
576 * Move the req'd B-tree elements from low in node2 to
577 * high in node1.
578 */
579 count = -count;
580 tmp = count * (uint)sizeof(xfs_da_node_entry_t);
581 btree_s = &node2->btree[0];
582 btree_d = &node1->btree[INT_GET(node1->hdr.count, ARCH_CONVERT)];
583 memcpy(btree_d, btree_s, tmp);
584 INT_MOD(node1->hdr.count, ARCH_CONVERT, count);
585 xfs_da_log_buf(tp, blk1->bp,
586 XFS_DA_LOGRANGE(node1, btree_d, tmp));
587
588 /*
589 * Move elements in node2 down to fill the hole.
590 */
591 tmp = INT_GET(node2->hdr.count, ARCH_CONVERT) - count;
592 tmp *= (uint)sizeof(xfs_da_node_entry_t);
593 btree_s = &node2->btree[count];
594 btree_d = &node2->btree[0];
595 memmove(btree_d, btree_s, tmp);
596 INT_MOD(node2->hdr.count, ARCH_CONVERT, -(count));
597 }
598
599 /*
600 * Log header of node 1 and all current bits of node 2.
601 */
602 xfs_da_log_buf(tp, blk1->bp,
603 XFS_DA_LOGRANGE(node1, &node1->hdr, sizeof(node1->hdr)));
604 xfs_da_log_buf(tp, blk2->bp,
605 XFS_DA_LOGRANGE(node2, &node2->hdr,
606 sizeof(node2->hdr) +
607 sizeof(node2->btree[0]) * INT_GET(node2->hdr.count, ARCH_CONVERT)));
608
609 /*
610 * Record the last hashval from each block for upward propagation.
611 * (note: don't use the swapped node pointers)
612 */
613 node1 = blk1->bp->data;
614 node2 = blk2->bp->data;
615 blk1->hashval = INT_GET(node1->btree[ INT_GET(node1->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
616 blk2->hashval = INT_GET(node2->btree[ INT_GET(node2->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
617
618 /*
619 * Adjust the expected index for insertion.
620 */
621 if (blk1->index >= INT_GET(node1->hdr.count, ARCH_CONVERT)) {
622 blk2->index = blk1->index - INT_GET(node1->hdr.count, ARCH_CONVERT);
623 blk1->index = INT_GET(node1->hdr.count, ARCH_CONVERT) + 1; /* make it invalid */
624 }
625 }
626
627 /*
628 * Add a new entry to an intermediate node.
629 */
630 STATIC void
631 xfs_da_node_add(xfs_da_state_t *state, xfs_da_state_blk_t *oldblk,
632 xfs_da_state_blk_t *newblk)
633 {
634 xfs_da_intnode_t *node;
635 xfs_da_node_entry_t *btree;
636 int tmp;
637 xfs_mount_t *mp;
638
639 node = oldblk->bp->data;
640 mp = state->mp;
641 ASSERT(INT_GET(node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
642 ASSERT((oldblk->index >= 0) && (oldblk->index <= INT_GET(node->hdr.count, ARCH_CONVERT)));
643 ASSERT(newblk->blkno != 0);
644 if (state->args->whichfork == XFS_DATA_FORK && XFS_DIR_IS_V2(mp))
645 ASSERT(newblk->blkno >= mp->m_dirleafblk &&
646 newblk->blkno < mp->m_dirfreeblk);
647
648 /*
649 * We may need to make some room before we insert the new node.
650 */
651 tmp = 0;
652 btree = &node->btree[ oldblk->index ];
653 if (oldblk->index < INT_GET(node->hdr.count, ARCH_CONVERT)) {
654 tmp = (INT_GET(node->hdr.count, ARCH_CONVERT) - oldblk->index) * (uint)sizeof(*btree);
655 memmove(btree + 1, btree, tmp);
656 }
657 INT_SET(btree->hashval, ARCH_CONVERT, newblk->hashval);
658 INT_SET(btree->before, ARCH_CONVERT, newblk->blkno);
659 xfs_da_log_buf(state->args->trans, oldblk->bp,
660 XFS_DA_LOGRANGE(node, btree, tmp + sizeof(*btree)));
661 INT_MOD(node->hdr.count, ARCH_CONVERT, +1);
662 xfs_da_log_buf(state->args->trans, oldblk->bp,
663 XFS_DA_LOGRANGE(node, &node->hdr, sizeof(node->hdr)));
664
665 /*
666 * Copy the last hash value from the oldblk to propagate upwards.
667 */
668 oldblk->hashval = INT_GET(node->btree[ INT_GET(node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
669 }
670
671 /*========================================================================
672 * Routines used for shrinking the Btree.
673 *========================================================================*/
674
675 /*
676 * Deallocate an empty leaf node, remove it from its parent,
677 * possibly deallocating that block, etc...
678 */
679 int
680 xfs_da_join(xfs_da_state_t *state)
681 {
682 xfs_da_state_blk_t *drop_blk, *save_blk;
683 int action, error;
684
685 action = 0;
686 drop_blk = &state->path.blk[ state->path.active-1 ];
687 save_blk = &state->altpath.blk[ state->path.active-1 ];
688 ASSERT(state->path.blk[0].magic == XFS_DA_NODE_MAGIC);
689 ASSERT(drop_blk->magic == XFS_ATTR_LEAF_MAGIC ||
690 drop_blk->magic == XFS_DIRX_LEAF_MAGIC(state->mp));
691
692 /*
693 * Walk back up the tree joining/deallocating as necessary.
694 * When we stop dropping blocks, break out.
695 */
696 for ( ; state->path.active >= 2; drop_blk--, save_blk--,
697 state->path.active--) {
698 /*
699 * See if we can combine the block with a neighbor.
700 * (action == 0) => no options, just leave
701 * (action == 1) => coalesce, then unlink
702 * (action == 2) => block empty, unlink it
703 */
704 switch (drop_blk->magic) {
705 case XFS_ATTR_LEAF_MAGIC:
706 #ifndef __KERNEL__
707 error = ENOTTY;
708 #else
709 error = xfs_attr_leaf_toosmall(state, &action);
710 #endif
711 if (error)
712 return(error);
713 if (action == 0)
714 return(0);
715 #ifdef __KERNEL__
716 xfs_attr_leaf_unbalance(state, drop_blk, save_blk);
717 #endif
718 break;
719 case XFS_DIR_LEAF_MAGIC:
720 ASSERT(XFS_DIR_IS_V1(state->mp));
721 error = xfs_dir_leaf_toosmall(state, &action);
722 if (error)
723 return(error);
724 if (action == 0)
725 return(0);
726 xfs_dir_leaf_unbalance(state, drop_blk, save_blk);
727 break;
728 case XFS_DIR2_LEAFN_MAGIC:
729 ASSERT(XFS_DIR_IS_V2(state->mp));
730 error = xfs_dir2_leafn_toosmall(state, &action);
731 if (error)
732 return error;
733 if (action == 0)
734 return 0;
735 xfs_dir2_leafn_unbalance(state, drop_blk, save_blk);
736 break;
737 case XFS_DA_NODE_MAGIC:
738 /*
739 * Remove the offending node, fixup hashvals,
740 * check for a toosmall neighbor.
741 */
742 xfs_da_node_remove(state, drop_blk);
743 xfs_da_fixhashpath(state, &state->path);
744 error = xfs_da_node_toosmall(state, &action);
745 if (error)
746 return(error);
747 if (action == 0)
748 return 0;
749 xfs_da_node_unbalance(state, drop_blk, save_blk);
750 break;
751 }
752 xfs_da_fixhashpath(state, &state->altpath);
753 error = xfs_da_blk_unlink(state, drop_blk, save_blk);
754 xfs_da_state_kill_altpath(state);
755 if (error)
756 return(error);
757 error = xfs_da_shrink_inode(state->args, drop_blk->blkno,
758 drop_blk->bp);
759 drop_blk->bp = NULL;
760 if (error)
761 return(error);
762 }
763 /*
764 * We joined all the way to the top. If it turns out that
765 * we only have one entry in the root, make the child block
766 * the new root.
767 */
768 xfs_da_node_remove(state, drop_blk);
769 xfs_da_fixhashpath(state, &state->path);
770 error = xfs_da_root_join(state, &state->path.blk[0]);
771 return(error);
772 }
773
774 /*
775 * We have only one entry in the root. Copy the only remaining child of
776 * the old root to block 0 as the new root node.
777 */
778 STATIC int
779 xfs_da_root_join(xfs_da_state_t *state, xfs_da_state_blk_t *root_blk)
780 {
781 xfs_da_intnode_t *oldroot;
782 /* REFERENCED */
783 xfs_da_blkinfo_t *blkinfo;
784 xfs_da_args_t *args;
785 xfs_dablk_t child;
786 xfs_dabuf_t *bp;
787 int error;
788
789 args = state->args;
790 ASSERT(args != NULL);
791 ASSERT(root_blk->magic == XFS_DA_NODE_MAGIC);
792 oldroot = root_blk->bp->data;
793 ASSERT(INT_GET(oldroot->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
794 ASSERT(!oldroot->hdr.info.forw);
795 ASSERT(!oldroot->hdr.info.back);
796
797 /*
798 * If the root has more than one child, then don't do anything.
799 */
800 if (INT_GET(oldroot->hdr.count, ARCH_CONVERT) > 1)
801 return(0);
802
803 /*
804 * Read in the (only) child block, then copy those bytes into
805 * the root block's buffer and free the original child block.
806 */
807 child = INT_GET(oldroot->btree[ 0 ].before, ARCH_CONVERT);
808 ASSERT(child != 0);
809 error = xfs_da_read_buf(args->trans, args->dp, child, -1, &bp,
810 args->whichfork);
811 if (error)
812 return(error);
813 ASSERT(bp != NULL);
814 blkinfo = bp->data;
815 if (INT_GET(oldroot->hdr.level, ARCH_CONVERT) == 1) {
816 ASSERT(INT_GET(blkinfo->magic, ARCH_CONVERT) == XFS_DIRX_LEAF_MAGIC(state->mp) ||
817 INT_GET(blkinfo->magic, ARCH_CONVERT) == XFS_ATTR_LEAF_MAGIC);
818 } else {
819 ASSERT(INT_GET(blkinfo->magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
820 }
821 ASSERT(!blkinfo->forw);
822 ASSERT(!blkinfo->back);
823 memcpy(root_blk->bp->data, bp->data, state->blocksize);
824 xfs_da_log_buf(args->trans, root_blk->bp, 0, state->blocksize - 1);
825 error = xfs_da_shrink_inode(args, child, bp);
826 return(error);
827 }
828
829 /*
830 * Check a node block and its neighbors to see if the block should be
831 * collapsed into one or the other neighbor. Always keep the block
832 * with the smaller block number.
833 * If the current block is over 50% full, don't try to join it, return 0.
834 * If the block is empty, fill in the state structure and return 2.
835 * If it can be collapsed, fill in the state structure and return 1.
836 * If nothing can be done, return 0.
837 */
838 STATIC int
839 xfs_da_node_toosmall(xfs_da_state_t *state, int *action)
840 {
841 xfs_da_intnode_t *node;
842 xfs_da_state_blk_t *blk;
843 xfs_da_blkinfo_t *info;
844 int count, forward, error, retval, i;
845 xfs_dablk_t blkno;
846 xfs_dabuf_t *bp;
847
848 /*
849 * Check for the degenerate case of the block being over 50% full.
850 * If so, it's not worth even looking to see if we might be able
851 * to coalesce with a sibling.
852 */
853 blk = &state->path.blk[ state->path.active-1 ];
854 info = blk->bp->data;
855 ASSERT(INT_GET(info->magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
856 node = (xfs_da_intnode_t *)info;
857 count = INT_GET(node->hdr.count, ARCH_CONVERT);
858 if (count > (state->node_ents >> 1)) {
859 *action = 0; /* blk over 50%, don't try to join */
860 return(0); /* blk over 50%, don't try to join */
861 }
862
863 /*
864 * Check for the degenerate case of the block being empty.
865 * If the block is empty, we'll simply delete it, no need to
866 * coalesce it with a sibling block. We choose (aribtrarily)
867 * to merge with the forward block unless it is NULL.
868 */
869 if (count == 0) {
870 /*
871 * Make altpath point to the block we want to keep and
872 * path point to the block we want to drop (this one).
873 */
874 forward = info->forw;
875 memcpy(&state->altpath, &state->path, sizeof(state->path));
876 error = xfs_da_path_shift(state, &state->altpath, forward,
877 0, &retval);
878 if (error)
879 return(error);
880 if (retval) {
881 *action = 0;
882 } else {
883 *action = 2;
884 }
885 return(0);
886 }
887
888 /*
889 * Examine each sibling block to see if we can coalesce with
890 * at least 25% free space to spare. We need to figure out
891 * whether to merge with the forward or the backward block.
892 * We prefer coalescing with the lower numbered sibling so as
893 * to shrink a directory over time.
894 */
895 /* start with smaller blk num */
896 forward = (INT_GET(info->forw, ARCH_CONVERT)
897 < INT_GET(info->back, ARCH_CONVERT));
898 for (i = 0; i < 2; forward = !forward, i++) {
899 if (forward)
900 blkno = INT_GET(info->forw, ARCH_CONVERT);
901 else
902 blkno = INT_GET(info->back, ARCH_CONVERT);
903 if (blkno == 0)
904 continue;
905 error = xfs_da_read_buf(state->args->trans, state->args->dp,
906 blkno, -1, &bp, state->args->whichfork);
907 if (error)
908 return(error);
909 ASSERT(bp != NULL);
910
911 node = (xfs_da_intnode_t *)info;
912 count = state->node_ents;
913 count -= state->node_ents >> 2;
914 count -= INT_GET(node->hdr.count, ARCH_CONVERT);
915 node = bp->data;
916 ASSERT(INT_GET(node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
917 count -= INT_GET(node->hdr.count, ARCH_CONVERT);
918 xfs_da_brelse(state->args->trans, bp);
919 if (count >= 0)
920 break; /* fits with at least 25% to spare */
921 }
922 if (i >= 2) {
923 *action = 0;
924 return(0);
925 }
926
927 /*
928 * Make altpath point to the block we want to keep (the lower
929 * numbered block) and path point to the block we want to drop.
930 */
931 memcpy(&state->altpath, &state->path, sizeof(state->path));
932 if (blkno < blk->blkno) {
933 error = xfs_da_path_shift(state, &state->altpath, forward,
934 0, &retval);
935 if (error) {
936 return(error);
937 }
938 if (retval) {
939 *action = 0;
940 return(0);
941 }
942 } else {
943 error = xfs_da_path_shift(state, &state->path, forward,
944 0, &retval);
945 if (error) {
946 return(error);
947 }
948 if (retval) {
949 *action = 0;
950 return(0);
951 }
952 }
953 *action = 1;
954 return(0);
955 }
956
957 /*
958 * Walk back up the tree adjusting hash values as necessary,
959 * when we stop making changes, return.
960 */
961 void
962 xfs_da_fixhashpath(xfs_da_state_t *state, xfs_da_state_path_t *path)
963 {
964 xfs_da_state_blk_t *blk;
965 xfs_da_intnode_t *node;
966 xfs_da_node_entry_t *btree;
967 xfs_dahash_t lasthash=0;
968 int level, count;
969
970 level = path->active-1;
971 blk = &path->blk[ level ];
972 switch (blk->magic) {
973 #ifdef __KERNEL__
974 case XFS_ATTR_LEAF_MAGIC:
975 lasthash = xfs_attr_leaf_lasthash(blk->bp, &count);
976 if (count == 0)
977 return;
978 break;
979 #endif
980 case XFS_DIR_LEAF_MAGIC:
981 ASSERT(XFS_DIR_IS_V1(state->mp));
982 lasthash = xfs_dir_leaf_lasthash(blk->bp, &count);
983 if (count == 0)
984 return;
985 break;
986 case XFS_DIR2_LEAFN_MAGIC:
987 ASSERT(XFS_DIR_IS_V2(state->mp));
988 lasthash = xfs_dir2_leafn_lasthash(blk->bp, &count);
989 if (count == 0)
990 return;
991 break;
992 case XFS_DA_NODE_MAGIC:
993 lasthash = xfs_da_node_lasthash(blk->bp, &count);
994 if (count == 0)
995 return;
996 break;
997 }
998 for (blk--, level--; level >= 0; blk--, level--) {
999 node = blk->bp->data;
1000 ASSERT(INT_GET(node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
1001 btree = &node->btree[ blk->index ];
1002 if (INT_GET(btree->hashval, ARCH_CONVERT) == lasthash)
1003 break;
1004 blk->hashval = lasthash;
1005 INT_SET(btree->hashval, ARCH_CONVERT, lasthash);
1006 xfs_da_log_buf(state->args->trans, blk->bp,
1007 XFS_DA_LOGRANGE(node, btree, sizeof(*btree)));
1008
1009 lasthash = INT_GET(node->btree[ INT_GET(node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
1010 }
1011 }
1012
1013 /*
1014 * Remove an entry from an intermediate node.
1015 */
1016 STATIC void
1017 xfs_da_node_remove(xfs_da_state_t *state, xfs_da_state_blk_t *drop_blk)
1018 {
1019 xfs_da_intnode_t *node;
1020 xfs_da_node_entry_t *btree;
1021 int tmp;
1022
1023 node = drop_blk->bp->data;
1024 ASSERT(drop_blk->index < INT_GET(node->hdr.count, ARCH_CONVERT));
1025 ASSERT(drop_blk->index >= 0);
1026
1027 /*
1028 * Copy over the offending entry, or just zero it out.
1029 */
1030 btree = &node->btree[drop_blk->index];
1031 if (drop_blk->index < (INT_GET(node->hdr.count, ARCH_CONVERT)-1)) {
1032 tmp = INT_GET(node->hdr.count, ARCH_CONVERT) - drop_blk->index - 1;
1033 tmp *= (uint)sizeof(xfs_da_node_entry_t);
1034 memmove(btree, btree + 1, tmp);
1035 xfs_da_log_buf(state->args->trans, drop_blk->bp,
1036 XFS_DA_LOGRANGE(node, btree, tmp));
1037 btree = &node->btree[ INT_GET(node->hdr.count, ARCH_CONVERT)-1 ];
1038 }
1039 memset((char *)btree, 0, sizeof(xfs_da_node_entry_t));
1040 xfs_da_log_buf(state->args->trans, drop_blk->bp,
1041 XFS_DA_LOGRANGE(node, btree, sizeof(*btree)));
1042 INT_MOD(node->hdr.count, ARCH_CONVERT, -1);
1043 xfs_da_log_buf(state->args->trans, drop_blk->bp,
1044 XFS_DA_LOGRANGE(node, &node->hdr, sizeof(node->hdr)));
1045
1046 /*
1047 * Copy the last hash value from the block to propagate upwards.
1048 */
1049 btree--;
1050 drop_blk->hashval = INT_GET(btree->hashval, ARCH_CONVERT);
1051 }
1052
1053 /*
1054 * Unbalance the btree elements between two intermediate nodes,
1055 * move all Btree elements from one node into another.
1056 */
1057 STATIC void
1058 xfs_da_node_unbalance(xfs_da_state_t *state, xfs_da_state_blk_t *drop_blk,
1059 xfs_da_state_blk_t *save_blk)
1060 {
1061 xfs_da_intnode_t *drop_node, *save_node;
1062 xfs_da_node_entry_t *btree;
1063 int tmp;
1064 xfs_trans_t *tp;
1065
1066 drop_node = drop_blk->bp->data;
1067 save_node = save_blk->bp->data;
1068 ASSERT(INT_GET(drop_node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
1069 ASSERT(INT_GET(save_node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
1070 tp = state->args->trans;
1071
1072 /*
1073 * If the dying block has lower hashvals, then move all the
1074 * elements in the remaining block up to make a hole.
1075 */
1076 if ((INT_GET(drop_node->btree[ 0 ].hashval, ARCH_CONVERT) < INT_GET(save_node->btree[ 0 ].hashval, ARCH_CONVERT)) ||
1077 (INT_GET(drop_node->btree[ INT_GET(drop_node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT) <
1078 INT_GET(save_node->btree[ INT_GET(save_node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT)))
1079 {
1080 btree = &save_node->btree[ INT_GET(drop_node->hdr.count, ARCH_CONVERT) ];
1081 tmp = INT_GET(save_node->hdr.count, ARCH_CONVERT) * (uint)sizeof(xfs_da_node_entry_t);
1082 memmove(btree, &save_node->btree[0], tmp);
1083 btree = &save_node->btree[0];
1084 xfs_da_log_buf(tp, save_blk->bp,
1085 XFS_DA_LOGRANGE(save_node, btree,
1086 (INT_GET(save_node->hdr.count, ARCH_CONVERT) + INT_GET(drop_node->hdr.count, ARCH_CONVERT)) *
1087 sizeof(xfs_da_node_entry_t)));
1088 } else {
1089 btree = &save_node->btree[ INT_GET(save_node->hdr.count, ARCH_CONVERT) ];
1090 xfs_da_log_buf(tp, save_blk->bp,
1091 XFS_DA_LOGRANGE(save_node, btree,
1092 INT_GET(drop_node->hdr.count, ARCH_CONVERT) *
1093 sizeof(xfs_da_node_entry_t)));
1094 }
1095
1096 /*
1097 * Move all the B-tree elements from drop_blk to save_blk.
1098 */
1099 tmp = INT_GET(drop_node->hdr.count, ARCH_CONVERT) * (uint)sizeof(xfs_da_node_entry_t);
1100 memcpy(btree, &drop_node->btree[0], tmp);
1101 INT_MOD(save_node->hdr.count, ARCH_CONVERT, INT_GET(drop_node->hdr.count, ARCH_CONVERT));
1102
1103 xfs_da_log_buf(tp, save_blk->bp,
1104 XFS_DA_LOGRANGE(save_node, &save_node->hdr,
1105 sizeof(save_node->hdr)));
1106
1107 /*
1108 * Save the last hashval in the remaining block for upward propagation.
1109 */
1110 save_blk->hashval = INT_GET(save_node->btree[ INT_GET(save_node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
1111 }
1112
1113 /*========================================================================
1114 * Routines used for finding things in the Btree.
1115 *========================================================================*/
1116
1117 /*
1118 * Walk down the Btree looking for a particular filename, filling
1119 * in the state structure as we go.
1120 *
1121 * We will set the state structure to point to each of the elements
1122 * in each of the nodes where either the hashval is or should be.
1123 *
1124 * We support duplicate hashval's so for each entry in the current
1125 * node that could contain the desired hashval, descend. This is a
1126 * pruned depth-first tree search.
1127 */
1128 int /* error */
1129 xfs_da_node_lookup_int(xfs_da_state_t *state, int *result)
1130 {
1131 xfs_da_state_blk_t *blk;
1132 xfs_da_blkinfo_t *curr;
1133 xfs_da_intnode_t *node;
1134 xfs_da_node_entry_t *btree;
1135 xfs_dablk_t blkno;
1136 int probe, span, max, error, retval;
1137 xfs_dahash_t hashval;
1138 xfs_da_args_t *args;
1139
1140 args = state->args;
1141
1142 /*
1143 * Descend thru the B-tree searching each level for the right
1144 * node to use, until the right hashval is found.
1145 */
1146 if (args->whichfork == XFS_DATA_FORK && XFS_DIR_IS_V2(state->mp))
1147 blkno = state->mp->m_dirleafblk;
1148 else
1149 blkno = 0;
1150 for (blk = &state->path.blk[0], state->path.active = 1;
1151 state->path.active <= XFS_DA_NODE_MAXDEPTH;
1152 blk++, state->path.active++) {
1153 /*
1154 * Read the next node down in the tree.
1155 */
1156 blk->blkno = blkno;
1157 error = xfs_da_read_buf(args->trans, args->dp, blkno,
1158 -1, &blk->bp, args->whichfork);
1159 if (error) {
1160 blk->blkno = 0;
1161 state->path.active--;
1162 return(error);
1163 }
1164 curr = blk->bp->data;
1165 ASSERT(INT_GET(curr->magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC ||
1166 INT_GET(curr->magic, ARCH_CONVERT) == XFS_DIRX_LEAF_MAGIC(state->mp) ||
1167 INT_GET(curr->magic, ARCH_CONVERT) == XFS_ATTR_LEAF_MAGIC);
1168
1169 /*
1170 * Search an intermediate node for a match.
1171 */
1172 blk->magic = INT_GET(curr->magic, ARCH_CONVERT);
1173 if (INT_GET(curr->magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC) {
1174 node = blk->bp->data;
1175 blk->hashval = INT_GET(node->btree[ INT_GET(node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
1176
1177 /*
1178 * Binary search. (note: small blocks will skip loop)
1179 */
1180 max = INT_GET(node->hdr.count, ARCH_CONVERT);
1181 probe = span = max / 2;
1182 hashval = args->hashval;
1183 for (btree = &node->btree[probe]; span > 4;
1184 btree = &node->btree[probe]) {
1185 span /= 2;
1186 if (INT_GET(btree->hashval, ARCH_CONVERT) < hashval)
1187 probe += span;
1188 else if (INT_GET(btree->hashval, ARCH_CONVERT) > hashval)
1189 probe -= span;
1190 else
1191 break;
1192 }
1193 ASSERT((probe >= 0) && (probe < max));
1194 ASSERT((span <= 4) || (INT_GET(btree->hashval, ARCH_CONVERT) == hashval));
1195
1196 /*
1197 * Since we may have duplicate hashval's, find the first
1198 * matching hashval in the node.
1199 */
1200 while ((probe > 0) && (INT_GET(btree->hashval, ARCH_CONVERT) >= hashval)) {
1201 btree--;
1202 probe--;
1203 }
1204 while ((probe < max) && (INT_GET(btree->hashval, ARCH_CONVERT) < hashval)) {
1205 btree++;
1206 probe++;
1207 }
1208
1209 /*
1210 * Pick the right block to descend on.
1211 */
1212 if (probe == max) {
1213 blk->index = max-1;
1214 blkno = INT_GET(node->btree[ max-1 ].before, ARCH_CONVERT);
1215 } else {
1216 blk->index = probe;
1217 blkno = INT_GET(btree->before, ARCH_CONVERT);
1218 }
1219 }
1220 #ifdef __KERNEL__
1221 else if (INT_GET(curr->magic, ARCH_CONVERT) == XFS_ATTR_LEAF_MAGIC) {
1222 blk->hashval = xfs_attr_leaf_lasthash(blk->bp, NULL);
1223 break;
1224 }
1225 #endif
1226 else if (INT_GET(curr->magic, ARCH_CONVERT) == XFS_DIR_LEAF_MAGIC) {
1227 blk->hashval = xfs_dir_leaf_lasthash(blk->bp, NULL);
1228 break;
1229 }
1230 else if (INT_GET(curr->magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC) {
1231 blk->hashval = xfs_dir2_leafn_lasthash(blk->bp, NULL);
1232 break;
1233 }
1234 }
1235
1236 /*
1237 * A leaf block that ends in the hashval that we are interested in
1238 * (final hashval == search hashval) means that the next block may
1239 * contain more entries with the same hashval, shift upward to the
1240 * next leaf and keep searching.
1241 */
1242 for (;;) {
1243 if (blk->magic == XFS_DIR_LEAF_MAGIC) {
1244 ASSERT(XFS_DIR_IS_V1(state->mp));
1245 retval = xfs_dir_leaf_lookup_int(blk->bp, args,
1246 &blk->index);
1247 } else if (blk->magic == XFS_DIR2_LEAFN_MAGIC) {
1248 ASSERT(XFS_DIR_IS_V2(state->mp));
1249 retval = xfs_dir2_leafn_lookup_int(blk->bp, args,
1250 &blk->index, state);
1251 }
1252 #ifdef __KERNEL__
1253 else if (blk->magic == XFS_ATTR_LEAF_MAGIC) {
1254 retval = xfs_attr_leaf_lookup_int(blk->bp, args);
1255 blk->index = args->index;
1256 args->blkno = blk->blkno;
1257 }
1258 #endif
1259 if (((retval == ENOENT) || (retval == ENOATTR)) &&
1260 (blk->hashval == args->hashval)) {
1261 error = xfs_da_path_shift(state, &state->path, 1, 1,
1262 &retval);
1263 if (error)
1264 return(error);
1265 if (retval == 0) {
1266 continue;
1267 }
1268 #ifdef __KERNEL__
1269 else if (blk->magic == XFS_ATTR_LEAF_MAGIC) {
1270 /* path_shift() gives ENOENT */
1271 retval = XFS_ERROR(ENOATTR);
1272 }
1273 #endif
1274 }
1275 break;
1276 }
1277 *result = retval;
1278 return(0);
1279 }
1280
1281 /*========================================================================
1282 * Utility routines.
1283 *========================================================================*/
1284
1285 /*
1286 * Link a new block into a doubly linked list of blocks (of whatever type).
1287 */
1288 int /* error */
1289 xfs_da_blk_link(xfs_da_state_t *state, xfs_da_state_blk_t *old_blk,
1290 xfs_da_state_blk_t *new_blk)
1291 {
1292 xfs_da_blkinfo_t *old_info, *new_info, *tmp_info;
1293 xfs_da_args_t *args;
1294 int before=0, error;
1295 xfs_dabuf_t *bp;
1296
1297 /*
1298 * Set up environment.
1299 */
1300 args = state->args;
1301 ASSERT(args != NULL);
1302 old_info = old_blk->bp->data;
1303 new_info = new_blk->bp->data;
1304 ASSERT(old_blk->magic == XFS_DA_NODE_MAGIC ||
1305 old_blk->magic == XFS_DIRX_LEAF_MAGIC(state->mp) ||
1306 old_blk->magic == XFS_ATTR_LEAF_MAGIC);
1307 ASSERT(old_blk->magic == INT_GET(old_info->magic, ARCH_CONVERT));
1308 ASSERT(new_blk->magic == INT_GET(new_info->magic, ARCH_CONVERT));
1309 ASSERT(old_blk->magic == new_blk->magic);
1310
1311 switch (old_blk->magic) {
1312 #ifdef __KERNEL__
1313 case XFS_ATTR_LEAF_MAGIC:
1314 before = xfs_attr_leaf_order(old_blk->bp, new_blk->bp);
1315 break;
1316 #endif
1317 case XFS_DIR_LEAF_MAGIC:
1318 ASSERT(XFS_DIR_IS_V1(state->mp));
1319 before = xfs_dir_leaf_order(old_blk->bp, new_blk->bp);
1320 break;
1321 case XFS_DIR2_LEAFN_MAGIC:
1322 ASSERT(XFS_DIR_IS_V2(state->mp));
1323 before = xfs_dir2_leafn_order(old_blk->bp, new_blk->bp);
1324 break;
1325 case XFS_DA_NODE_MAGIC:
1326 before = xfs_da_node_order(old_blk->bp, new_blk->bp);
1327 break;
1328 }
1329
1330 /*
1331 * Link blocks in appropriate order.
1332 */
1333 if (before) {
1334 /*
1335 * Link new block in before existing block.
1336 */
1337 INT_SET(new_info->forw, ARCH_CONVERT, old_blk->blkno);
1338 new_info->back = old_info->back; /* INT_: direct copy */
1339 if (INT_GET(old_info->back, ARCH_CONVERT)) {
1340 error = xfs_da_read_buf(args->trans, args->dp,
1341 INT_GET(old_info->back,
1342 ARCH_CONVERT), -1, &bp,
1343 args->whichfork);
1344 if (error)
1345 return(error);
1346 ASSERT(bp != NULL);
1347 tmp_info = bp->data;
1348 ASSERT(INT_GET(tmp_info->magic, ARCH_CONVERT) == INT_GET(old_info->magic, ARCH_CONVERT));
1349 ASSERT(INT_GET(tmp_info->forw, ARCH_CONVERT) == old_blk->blkno);
1350 INT_SET(tmp_info->forw, ARCH_CONVERT, new_blk->blkno);
1351 xfs_da_log_buf(args->trans, bp, 0, sizeof(*tmp_info)-1);
1352 xfs_da_buf_done(bp);
1353 }
1354 INT_SET(old_info->back, ARCH_CONVERT, new_blk->blkno);
1355 } else {
1356 /*
1357 * Link new block in after existing block.
1358 */
1359 new_info->forw = old_info->forw; /* INT_: direct copy */
1360 INT_SET(new_info->back, ARCH_CONVERT, old_blk->blkno);
1361 if (INT_GET(old_info->forw, ARCH_CONVERT)) {
1362 error = xfs_da_read_buf(args->trans, args->dp,
1363 INT_GET(old_info->forw, ARCH_CONVERT), -1, &bp,
1364 args->whichfork);
1365 if (error)
1366 return(error);
1367 ASSERT(bp != NULL);
1368 tmp_info = bp->data;
1369 ASSERT(INT_GET(tmp_info->magic, ARCH_CONVERT)
1370 == INT_GET(old_info->magic, ARCH_CONVERT));
1371 ASSERT(INT_GET(tmp_info->back, ARCH_CONVERT)
1372 == old_blk->blkno);
1373 INT_SET(tmp_info->back, ARCH_CONVERT, new_blk->blkno);
1374 xfs_da_log_buf(args->trans, bp, 0, sizeof(*tmp_info)-1);
1375 xfs_da_buf_done(bp);
1376 }
1377 INT_SET(old_info->forw, ARCH_CONVERT, new_blk->blkno);
1378 }
1379
1380 xfs_da_log_buf(args->trans, old_blk->bp, 0, sizeof(*tmp_info) - 1);
1381 xfs_da_log_buf(args->trans, new_blk->bp, 0, sizeof(*tmp_info) - 1);
1382 return(0);
1383 }
1384
1385 /*
1386 * Compare two intermediate nodes for "order".
1387 */
1388 STATIC int
1389 xfs_da_node_order(xfs_dabuf_t *node1_bp, xfs_dabuf_t *node2_bp)
1390 {
1391 xfs_da_intnode_t *node1, *node2;
1392
1393 node1 = node1_bp->data;
1394 node2 = node2_bp->data;
1395 ASSERT((INT_GET(node1->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC) &&
1396 (INT_GET(node2->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC));
1397 if ((INT_GET(node1->hdr.count, ARCH_CONVERT) > 0) && (INT_GET(node2->hdr.count, ARCH_CONVERT) > 0) &&
1398 ((INT_GET(node2->btree[ 0 ].hashval, ARCH_CONVERT) <
1399 INT_GET(node1->btree[ 0 ].hashval, ARCH_CONVERT)) ||
1400 (INT_GET(node2->btree[ INT_GET(node2->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT) <
1401 INT_GET(node1->btree[ INT_GET(node1->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT)))) {
1402 return(1);
1403 }
1404 return(0);
1405 }
1406
1407 /*
1408 * Pick up the last hashvalue from an intermediate node.
1409 */
1410 STATIC uint
1411 xfs_da_node_lasthash(xfs_dabuf_t *bp, int *count)
1412 {
1413 xfs_da_intnode_t *node;
1414
1415 node = bp->data;
1416 ASSERT(INT_GET(node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
1417 if (count)
1418 *count = INT_GET(node->hdr.count, ARCH_CONVERT);
1419 if (!node->hdr.count)
1420 return(0);
1421 return(INT_GET(node->btree[ INT_GET(node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT));
1422 }
1423
1424 /*
1425 * Unlink a block from a doubly linked list of blocks.
1426 */
1427 int /* error */
1428 xfs_da_blk_unlink(xfs_da_state_t *state, xfs_da_state_blk_t *drop_blk,
1429 xfs_da_state_blk_t *save_blk)
1430 {
1431 xfs_da_blkinfo_t *drop_info, *save_info, *tmp_info;
1432 xfs_da_args_t *args;
1433 xfs_dabuf_t *bp;
1434 int error;
1435
1436 /*
1437 * Set up environment.
1438 */
1439 args = state->args;
1440 ASSERT(args != NULL);
1441 save_info = save_blk->bp->data;
1442 drop_info = drop_blk->bp->data;
1443 ASSERT(save_blk->magic == XFS_DA_NODE_MAGIC ||
1444 save_blk->magic == XFS_DIRX_LEAF_MAGIC(state->mp) ||
1445 save_blk->magic == XFS_ATTR_LEAF_MAGIC);
1446 ASSERT(save_blk->magic == INT_GET(save_info->magic, ARCH_CONVERT));
1447 ASSERT(drop_blk->magic == INT_GET(drop_info->magic, ARCH_CONVERT));
1448 ASSERT(save_blk->magic == drop_blk->magic);
1449 ASSERT((INT_GET(save_info->forw, ARCH_CONVERT) == drop_blk->blkno) ||
1450 (INT_GET(save_info->back, ARCH_CONVERT) == drop_blk->blkno));
1451 ASSERT((INT_GET(drop_info->forw, ARCH_CONVERT) == save_blk->blkno) ||
1452 (INT_GET(drop_info->back, ARCH_CONVERT) == save_blk->blkno));
1453
1454 /*
1455 * Unlink the leaf block from the doubly linked chain of leaves.
1456 */
1457 if (INT_GET(save_info->back, ARCH_CONVERT) == drop_blk->blkno) {
1458 save_info->back = drop_info->back; /* INT_: direct copy */
1459 if (INT_GET(drop_info->back, ARCH_CONVERT)) {
1460 error = xfs_da_read_buf(args->trans, args->dp,
1461 INT_GET(drop_info->back,
1462 ARCH_CONVERT), -1, &bp,
1463 args->whichfork);
1464 if (error)
1465 return(error);
1466 ASSERT(bp != NULL);
1467 tmp_info = bp->data;
1468 ASSERT(INT_GET(tmp_info->magic, ARCH_CONVERT) == INT_GET(save_info->magic, ARCH_CONVERT));
1469 ASSERT(INT_GET(tmp_info->forw, ARCH_CONVERT) == drop_blk->blkno);
1470 INT_SET(tmp_info->forw, ARCH_CONVERT, save_blk->blkno);
1471 xfs_da_log_buf(args->trans, bp, 0,
1472 sizeof(*tmp_info) - 1);
1473 xfs_da_buf_done(bp);
1474 }
1475 } else {
1476 save_info->forw = drop_info->forw; /* INT_: direct copy */
1477 if (INT_GET(drop_info->forw, ARCH_CONVERT)) {
1478 error = xfs_da_read_buf(args->trans, args->dp,
1479 INT_GET(drop_info->forw, ARCH_CONVERT), -1, &bp,
1480 args->whichfork);
1481 if (error)
1482 return(error);
1483 ASSERT(bp != NULL);
1484 tmp_info = bp->data;
1485 ASSERT(INT_GET(tmp_info->magic, ARCH_CONVERT)
1486 == INT_GET(save_info->magic, ARCH_CONVERT));
1487 ASSERT(INT_GET(tmp_info->back, ARCH_CONVERT)
1488 == drop_blk->blkno);
1489 INT_SET(tmp_info->back, ARCH_CONVERT, save_blk->blkno);
1490 xfs_da_log_buf(args->trans, bp, 0,
1491 sizeof(*tmp_info) - 1);
1492 xfs_da_buf_done(bp);
1493 }
1494 }
1495
1496 xfs_da_log_buf(args->trans, save_blk->bp, 0, sizeof(*save_info) - 1);
1497 return(0);
1498 }
1499
1500 /*
1501 * Move a path "forward" or "!forward" one block at the current level.
1502 *
1503 * This routine will adjust a "path" to point to the next block
1504 * "forward" (higher hashvalues) or "!forward" (lower hashvals) in the
1505 * Btree, including updating pointers to the intermediate nodes between
1506 * the new bottom and the root.
1507 */
1508 int /* error */
1509 xfs_da_path_shift(xfs_da_state_t *state, xfs_da_state_path_t *path,
1510 int forward, int release, int *result)
1511 {
1512 xfs_da_state_blk_t *blk;
1513 xfs_da_blkinfo_t *info;
1514 xfs_da_intnode_t *node;
1515 xfs_da_args_t *args;
1516 xfs_dablk_t blkno=0;
1517 int level, error;
1518
1519 /*
1520 * Roll up the Btree looking for the first block where our
1521 * current index is not at the edge of the block. Note that
1522 * we skip the bottom layer because we want the sibling block.
1523 */
1524 args = state->args;
1525 ASSERT(args != NULL);
1526 ASSERT(path != NULL);
1527 ASSERT((path->active > 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1528 level = (path->active-1) - 1; /* skip bottom layer in path */
1529 for (blk = &path->blk[level]; level >= 0; blk--, level--) {
1530 ASSERT(blk->bp != NULL);
1531 node = blk->bp->data;
1532 ASSERT(INT_GET(node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
1533 if (forward && (blk->index < INT_GET(node->hdr.count, ARCH_CONVERT)-1)) {
1534 blk->index++;
1535 blkno = INT_GET(node->btree[ blk->index ].before, ARCH_CONVERT);
1536 break;
1537 } else if (!forward && (blk->index > 0)) {
1538 blk->index--;
1539 blkno = INT_GET(node->btree[ blk->index ].before, ARCH_CONVERT);
1540 break;
1541 }
1542 }
1543 if (level < 0) {
1544 *result = XFS_ERROR(ENOENT); /* we're out of our tree */
1545 ASSERT(args->oknoent);
1546 return(0);
1547 }
1548
1549 /*
1550 * Roll down the edge of the subtree until we reach the
1551 * same depth we were at originally.
1552 */
1553 for (blk++, level++; level < path->active; blk++, level++) {
1554 /*
1555 * Release the old block.
1556 * (if it's dirty, trans won't actually let go)
1557 */
1558 if (release)
1559 xfs_da_brelse(args->trans, blk->bp);
1560
1561 /*
1562 * Read the next child block.
1563 */
1564 blk->blkno = blkno;
1565 error = xfs_da_read_buf(args->trans, args->dp, blkno, -1,
1566 &blk->bp, args->whichfork);
1567 if (error)
1568 return(error);
1569 ASSERT(blk->bp != NULL);
1570 info = blk->bp->data;
1571 ASSERT(INT_GET(info->magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC ||
1572 INT_GET(info->magic, ARCH_CONVERT) == XFS_DIRX_LEAF_MAGIC(state->mp) ||
1573 INT_GET(info->magic, ARCH_CONVERT) == XFS_ATTR_LEAF_MAGIC);
1574 blk->magic = INT_GET(info->magic, ARCH_CONVERT);
1575 if (INT_GET(info->magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC) {
1576 node = (xfs_da_intnode_t *)info;
1577 blk->hashval = INT_GET(node->btree[ INT_GET(node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
1578 if (forward)
1579 blk->index = 0;
1580 else
1581 blk->index = INT_GET(node->hdr.count, ARCH_CONVERT)-1;
1582 blkno = INT_GET(node->btree[ blk->index ].before, ARCH_CONVERT);
1583 } else {
1584 ASSERT(level == path->active-1);
1585 blk->index = 0;
1586 switch(blk->magic) {
1587 #ifdef __KERNEL__
1588 case XFS_ATTR_LEAF_MAGIC:
1589 blk->hashval = xfs_attr_leaf_lasthash(blk->bp,
1590 NULL);
1591 break;
1592 #endif
1593 case XFS_DIR_LEAF_MAGIC:
1594 ASSERT(XFS_DIR_IS_V1(state->mp));
1595 blk->hashval = xfs_dir_leaf_lasthash(blk->bp,
1596 NULL);
1597 break;
1598 case XFS_DIR2_LEAFN_MAGIC:
1599 ASSERT(XFS_DIR_IS_V2(state->mp));
1600 blk->hashval = xfs_dir2_leafn_lasthash(blk->bp,
1601 NULL);
1602 break;
1603 default:
1604 ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC ||
1605 blk->magic ==
1606 XFS_DIRX_LEAF_MAGIC(state->mp));
1607 break;
1608 }
1609 }
1610 }
1611 *result = 0;
1612 return(0);
1613 }
1614
1615
1616 /*========================================================================
1617 * Utility routines.
1618 *========================================================================*/
1619
1620 /*
1621 * Implement a simple hash on a character string.
1622 * Rotate the hash value by 7 bits, then XOR each character in.
1623 * This is implemented with some source-level loop unrolling.
1624 */
1625 xfs_dahash_t
1626 xfs_da_hashname(uchar_t *name, int namelen)
1627 {
1628 xfs_dahash_t hash;
1629
1630 #ifdef SLOWVERSION
1631 /*
1632 * This is the old one-byte-at-a-time version.
1633 */
1634 for (hash = 0; namelen > 0; namelen--)
1635 hash = *name++ ^ rol32(hash, 7);
1636
1637 return(hash);
1638 #else
1639 /*
1640 * Do four characters at a time as long as we can.
1641 */
1642 for (hash = 0; namelen >= 4; namelen -= 4, name += 4)
1643 hash = (name[0] << 21) ^ (name[1] << 14) ^ (name[2] << 7) ^
1644 (name[3] << 0) ^ rol32(hash, 7 * 4);
1645
1646 /*
1647 * Now do the rest of the characters.
1648 */
1649 switch (namelen) {
1650 case 3:
1651 return (name[0] << 14) ^ (name[1] << 7) ^ (name[2] << 0) ^
1652 rol32(hash, 7 * 3);
1653 case 2:
1654 return (name[0] << 7) ^ (name[1] << 0) ^ rol32(hash, 7 * 2);
1655 case 1:
1656 return (name[0] << 0) ^ rol32(hash, 7 * 1);
1657 case 0:
1658 return hash;
1659 }
1660 /* NOTREACHED */
1661 #endif
1662 return 0; /* keep gcc happy */
1663 }
1664
1665 /*
1666 * Add a block to the btree ahead of the file.
1667 * Return the new block number to the caller.
1668 */
1669 int
1670 xfs_da_grow_inode(xfs_da_args_t *args, xfs_dablk_t *new_blkno)
1671 {
1672 xfs_fileoff_t bno, b;
1673 xfs_bmbt_irec_t map;
1674 xfs_bmbt_irec_t *mapp;
1675 xfs_inode_t *dp;
1676 int nmap, error, w, count, c, got, i, mapi;
1677 xfs_fsize_t size;
1678 xfs_trans_t *tp;
1679 xfs_mount_t *mp;
1680
1681 dp = args->dp;
1682 mp = dp->i_mount;
1683 w = args->whichfork;
1684 tp = args->trans;
1685 /*
1686 * For new directories adjust the file offset and block count.
1687 */
1688 if (w == XFS_DATA_FORK && XFS_DIR_IS_V2(mp)) {
1689 bno = mp->m_dirleafblk;
1690 count = mp->m_dirblkfsbs;
1691 } else {
1692 bno = 0;
1693 count = 1;
1694 }
1695 /*
1696 * Find a spot in the file space to put the new block.
1697 */
1698 if ((error = xfs_bmap_first_unused(tp, dp, count, &bno, w))) {
1699 return error;
1700 }
1701 if (w == XFS_DATA_FORK && XFS_DIR_IS_V2(mp))
1702 ASSERT(bno >= mp->m_dirleafblk && bno < mp->m_dirfreeblk);
1703 /*
1704 * Try mapping it in one filesystem block.
1705 */
1706 nmap = 1;
1707 ASSERT(args->firstblock != NULL);
1708 if ((error = xfs_bmapi(tp, dp, bno, count,
1709 XFS_BMAPI_AFLAG(w)|XFS_BMAPI_WRITE|XFS_BMAPI_METADATA|
1710 XFS_BMAPI_CONTIG,
1711 args->firstblock, args->total, &map, &nmap,
1712 args->flist))) {
1713 return error;
1714 }
1715 ASSERT(nmap <= 1);
1716 if (nmap == 1) {
1717 mapp = &map;
1718 mapi = 1;
1719 }
1720 /*
1721 * If we didn't get it and the block might work if fragmented,
1722 * try without the CONTIG flag. Loop until we get it all.
1723 */
1724 else if (nmap == 0 && count > 1) {
1725 mapp = kmem_alloc(sizeof(*mapp) * count, KM_SLEEP);
1726 for (b = bno, mapi = 0; b < bno + count; ) {
1727 nmap = MIN(XFS_BMAP_MAX_NMAP, count);
1728 c = (int)(bno + count - b);
1729 if ((error = xfs_bmapi(tp, dp, b, c,
1730 XFS_BMAPI_AFLAG(w)|XFS_BMAPI_WRITE|
1731 XFS_BMAPI_METADATA,
1732 args->firstblock, args->total,
1733 &mapp[mapi], &nmap, args->flist))) {
1734 kmem_free(mapp, sizeof(*mapp) * count);
1735 return error;
1736 }
1737 if (nmap < 1)
1738 break;
1739 mapi += nmap;
1740 b = mapp[mapi - 1].br_startoff +
1741 mapp[mapi - 1].br_blockcount;
1742 }
1743 } else {
1744 mapi = 0;
1745 mapp = NULL;
1746 }
1747 /*
1748 * Count the blocks we got, make sure it matches the total.
1749 */
1750 for (i = 0, got = 0; i < mapi; i++)
1751 got += mapp[i].br_blockcount;
1752 if (got != count || mapp[0].br_startoff != bno ||
1753 mapp[mapi - 1].br_startoff + mapp[mapi - 1].br_blockcount !=
1754 bno + count) {
1755 if (mapp != &map)
1756 kmem_free(mapp, sizeof(*mapp) * count);
1757 return XFS_ERROR(ENOSPC);
1758 }
1759 if (mapp != &map)
1760 kmem_free(mapp, sizeof(*mapp) * count);
1761 *new_blkno = (xfs_dablk_t)bno;
1762 /*
1763 * For version 1 directories, adjust the file size if it changed.
1764 */
1765 if (w == XFS_DATA_FORK && XFS_DIR_IS_V1(mp)) {
1766 ASSERT(mapi == 1);
1767 if ((error = xfs_bmap_last_offset(tp, dp, &bno, w)))
1768 return error;
1769 size = XFS_FSB_TO_B(mp, bno);
1770 if (size != dp->i_d.di_size) {
1771 dp->i_d.di_size = size;
1772 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1773 }
1774 }
1775 return 0;
1776 }
1777
1778 /*
1779 * Ick. We need to always be able to remove a btree block, even
1780 * if there's no space reservation because the filesystem is full.
1781 * This is called if xfs_bunmapi on a btree block fails due to ENOSPC.
1782 * It swaps the target block with the last block in the file. The
1783 * last block in the file can always be removed since it can't cause
1784 * a bmap btree split to do that.
1785 */
1786 STATIC int
1787 xfs_da_swap_lastblock(xfs_da_args_t *args, xfs_dablk_t *dead_blknop,
1788 xfs_dabuf_t **dead_bufp)
1789 {
1790 xfs_dablk_t dead_blkno, last_blkno, sib_blkno, par_blkno;
1791 xfs_dabuf_t *dead_buf, *last_buf, *sib_buf, *par_buf;
1792 xfs_fileoff_t lastoff;
1793 xfs_inode_t *ip;
1794 xfs_trans_t *tp;
1795 xfs_mount_t *mp;
1796 int error, w, entno, level, dead_level;
1797 xfs_da_blkinfo_t *dead_info, *sib_info;
1798 xfs_da_intnode_t *par_node, *dead_node;
1799 xfs_dir_leafblock_t *dead_leaf;
1800 xfs_dir2_leaf_t *dead_leaf2;
1801 xfs_dahash_t dead_hash;
1802
1803 dead_buf = *dead_bufp;
1804 dead_blkno = *dead_blknop;
1805 tp = args->trans;
1806 ip = args->dp;
1807 w = args->whichfork;
1808 ASSERT(w == XFS_DATA_FORK);
1809 mp = ip->i_mount;
1810 if (XFS_DIR_IS_V2(mp)) {
1811 lastoff = mp->m_dirfreeblk;
1812 error = xfs_bmap_last_before(tp, ip, &lastoff, w);
1813 } else
1814 error = xfs_bmap_last_offset(tp, ip, &lastoff, w);
1815 if (error)
1816 return error;
1817 if (unlikely(lastoff == 0)) {
1818 XFS_ERROR_REPORT("xfs_da_swap_lastblock(1)", XFS_ERRLEVEL_LOW,
1819 mp);
1820 return XFS_ERROR(EFSCORRUPTED);
1821 }
1822 /*
1823 * Read the last block in the btree space.
1824 */
1825 last_blkno = (xfs_dablk_t)lastoff - mp->m_dirblkfsbs;
1826 if ((error = xfs_da_read_buf(tp, ip, last_blkno, -1, &last_buf, w)))
1827 return error;
1828 /*
1829 * Copy the last block into the dead buffer and log it.
1830 */
1831 memcpy(dead_buf->data, last_buf->data, mp->m_dirblksize);
1832 xfs_da_log_buf(tp, dead_buf, 0, mp->m_dirblksize - 1);
1833 dead_info = dead_buf->data;
1834 /*
1835 * Get values from the moved block.
1836 */
1837 if (INT_GET(dead_info->magic, ARCH_CONVERT) == XFS_DIR_LEAF_MAGIC) {
1838 ASSERT(XFS_DIR_IS_V1(mp));
1839 dead_leaf = (xfs_dir_leafblock_t *)dead_info;
1840 dead_level = 0;
1841 dead_hash =
1842 INT_GET(dead_leaf->entries[INT_GET(dead_leaf->hdr.count, ARCH_CONVERT) - 1].hashval, ARCH_CONVERT);
1843 } else if (INT_GET(dead_info->magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC) {
1844 ASSERT(XFS_DIR_IS_V2(mp));
1845 dead_leaf2 = (xfs_dir2_leaf_t *)dead_info;
1846 dead_level = 0;
1847 dead_hash = INT_GET(dead_leaf2->ents[INT_GET(dead_leaf2->hdr.count, ARCH_CONVERT) - 1].hashval, ARCH_CONVERT);
1848 } else {
1849 ASSERT(INT_GET(dead_info->magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
1850 dead_node = (xfs_da_intnode_t *)dead_info;
1851 dead_level = INT_GET(dead_node->hdr.level, ARCH_CONVERT);
1852 dead_hash = INT_GET(dead_node->btree[INT_GET(dead_node->hdr.count, ARCH_CONVERT) - 1].hashval, ARCH_CONVERT);
1853 }
1854 sib_buf = par_buf = NULL;
1855 /*
1856 * If the moved block has a left sibling, fix up the pointers.
1857 */
1858 if ((sib_blkno = INT_GET(dead_info->back, ARCH_CONVERT))) {
1859 if ((error = xfs_da_read_buf(tp, ip, sib_blkno, -1, &sib_buf, w)))
1860 goto done;
1861 sib_info = sib_buf->data;
1862 if (unlikely(
1863 INT_GET(sib_info->forw, ARCH_CONVERT) != last_blkno ||
1864 INT_GET(sib_info->magic, ARCH_CONVERT) != INT_GET(dead_info->magic, ARCH_CONVERT))) {
1865 XFS_ERROR_REPORT("xfs_da_swap_lastblock(2)",
1866 XFS_ERRLEVEL_LOW, mp);
1867 error = XFS_ERROR(EFSCORRUPTED);
1868 goto done;
1869 }
1870 INT_SET(sib_info->forw, ARCH_CONVERT, dead_blkno);
1871 xfs_da_log_buf(tp, sib_buf,
1872 XFS_DA_LOGRANGE(sib_info, &sib_info->forw,
1873 sizeof(sib_info->forw)));
1874 xfs_da_buf_done(sib_buf);
1875 sib_buf = NULL;
1876 }
1877 /*
1878 * If the moved block has a right sibling, fix up the pointers.
1879 */
1880 if ((sib_blkno = INT_GET(dead_info->forw, ARCH_CONVERT))) {
1881 if ((error = xfs_da_read_buf(tp, ip, sib_blkno, -1, &sib_buf, w)))
1882 goto done;
1883 sib_info = sib_buf->data;
1884 if (unlikely(
1885 INT_GET(sib_info->back, ARCH_CONVERT) != last_blkno
1886 || INT_GET(sib_info->magic, ARCH_CONVERT)
1887 != INT_GET(dead_info->magic, ARCH_CONVERT))) {
1888 XFS_ERROR_REPORT("xfs_da_swap_lastblock(3)",
1889 XFS_ERRLEVEL_LOW, mp);
1890 error = XFS_ERROR(EFSCORRUPTED);
1891 goto done;
1892 }
1893 INT_SET(sib_info->back, ARCH_CONVERT, dead_blkno);
1894 xfs_da_log_buf(tp, sib_buf,
1895 XFS_DA_LOGRANGE(sib_info, &sib_info->back,
1896 sizeof(sib_info->back)));
1897 xfs_da_buf_done(sib_buf);
1898 sib_buf = NULL;
1899 }
1900 par_blkno = XFS_DIR_IS_V1(mp) ? 0 : mp->m_dirleafblk;
1901 level = -1;
1902 /*
1903 * Walk down the tree looking for the parent of the moved block.
1904 */
1905 for (;;) {
1906 if ((error = xfs_da_read_buf(tp, ip, par_blkno, -1, &par_buf, w)))
1907 goto done;
1908 par_node = par_buf->data;
1909 if (unlikely(
1910 INT_GET(par_node->hdr.info.magic, ARCH_CONVERT) != XFS_DA_NODE_MAGIC ||
1911 (level >= 0 && level != INT_GET(par_node->hdr.level, ARCH_CONVERT) + 1))) {
1912 XFS_ERROR_REPORT("xfs_da_swap_lastblock(4)",
1913 XFS_ERRLEVEL_LOW, mp);
1914 error = XFS_ERROR(EFSCORRUPTED);
1915 goto done;
1916 }
1917 level = INT_GET(par_node->hdr.level, ARCH_CONVERT);
1918 for (entno = 0;
1919 entno < INT_GET(par_node->hdr.count, ARCH_CONVERT) &&
1920 INT_GET(par_node->btree[entno].hashval, ARCH_CONVERT) < dead_hash;
1921 entno++)
1922 continue;
1923 if (unlikely(entno == INT_GET(par_node->hdr.count, ARCH_CONVERT))) {
1924 XFS_ERROR_REPORT("xfs_da_swap_lastblock(5)",
1925 XFS_ERRLEVEL_LOW, mp);
1926 error = XFS_ERROR(EFSCORRUPTED);
1927 goto done;
1928 }
1929 par_blkno = INT_GET(par_node->btree[entno].before, ARCH_CONVERT);
1930 if (level == dead_level + 1)
1931 break;
1932 xfs_da_brelse(tp, par_buf);
1933 par_buf = NULL;
1934 }
1935 /*
1936 * We're in the right parent block.
1937 * Look for the right entry.
1938 */
1939 for (;;) {
1940 for (;
1941 entno < INT_GET(par_node->hdr.count, ARCH_CONVERT) &&
1942 INT_GET(par_node->btree[entno].before, ARCH_CONVERT) != last_blkno;
1943 entno++)
1944 continue;
1945 if (entno < INT_GET(par_node->hdr.count, ARCH_CONVERT))
1946 break;
1947 par_blkno = INT_GET(par_node->hdr.info.forw, ARCH_CONVERT);
1948 xfs_da_brelse(tp, par_buf);
1949 par_buf = NULL;
1950 if (unlikely(par_blkno == 0)) {
1951 XFS_ERROR_REPORT("xfs_da_swap_lastblock(6)",
1952 XFS_ERRLEVEL_LOW, mp);
1953 error = XFS_ERROR(EFSCORRUPTED);
1954 goto done;
1955 }
1956 if ((error = xfs_da_read_buf(tp, ip, par_blkno, -1, &par_buf, w)))
1957 goto done;
1958 par_node = par_buf->data;
1959 if (unlikely(
1960 INT_GET(par_node->hdr.level, ARCH_CONVERT) != level ||
1961 INT_GET(par_node->hdr.info.magic, ARCH_CONVERT) != XFS_DA_NODE_MAGIC)) {
1962 XFS_ERROR_REPORT("xfs_da_swap_lastblock(7)",
1963 XFS_ERRLEVEL_LOW, mp);
1964 error = XFS_ERROR(EFSCORRUPTED);
1965 goto done;
1966 }
1967 entno = 0;
1968 }
1969 /*
1970 * Update the parent entry pointing to the moved block.
1971 */
1972 INT_SET(par_node->btree[entno].before, ARCH_CONVERT, dead_blkno);
1973 xfs_da_log_buf(tp, par_buf,
1974 XFS_DA_LOGRANGE(par_node, &par_node->btree[entno].before,
1975 sizeof(par_node->btree[entno].before)));
1976 xfs_da_buf_done(par_buf);
1977 xfs_da_buf_done(dead_buf);
1978 *dead_blknop = last_blkno;
1979 *dead_bufp = last_buf;
1980 return 0;
1981 done:
1982 if (par_buf)
1983 xfs_da_brelse(tp, par_buf);
1984 if (sib_buf)
1985 xfs_da_brelse(tp, sib_buf);
1986 xfs_da_brelse(tp, last_buf);
1987 return error;
1988 }
1989
1990 /*
1991 * Remove a btree block from a directory or attribute.
1992 */
1993 int
1994 xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno,
1995 xfs_dabuf_t *dead_buf)
1996 {
1997 xfs_inode_t *dp;
1998 int done, error, w, count;
1999 xfs_fileoff_t bno;
2000 xfs_fsize_t size;
2001 xfs_trans_t *tp;
2002 xfs_mount_t *mp;
2003
2004 dp = args->dp;
2005 w = args->whichfork;
2006 tp = args->trans;
2007 mp = dp->i_mount;
2008 if (w == XFS_DATA_FORK && XFS_DIR_IS_V2(mp))
2009 count = mp->m_dirblkfsbs;
2010 else
2011 count = 1;
2012 for (;;) {
2013 /*
2014 * Remove extents. If we get ENOSPC for a dir we have to move
2015 * the last block to the place we want to kill.
2016 */
2017 if ((error = xfs_bunmapi(tp, dp, dead_blkno, count,
2018 XFS_BMAPI_AFLAG(w)|XFS_BMAPI_METADATA,
2019 0, args->firstblock, args->flist,
2020 &done)) == ENOSPC) {
2021 if (w != XFS_DATA_FORK)
2022 goto done;
2023 if ((error = xfs_da_swap_lastblock(args, &dead_blkno,
2024 &dead_buf)))
2025 goto done;
2026 } else if (error)
2027 goto done;
2028 else
2029 break;
2030 }
2031 ASSERT(done);
2032 xfs_da_binval(tp, dead_buf);
2033 /*
2034 * Adjust the directory size for version 1.
2035 */
2036 if (w == XFS_DATA_FORK && XFS_DIR_IS_V1(mp)) {
2037 if ((error = xfs_bmap_last_offset(tp, dp, &bno, w)))
2038 return error;
2039 size = XFS_FSB_TO_B(dp->i_mount, bno);
2040 if (size != dp->i_d.di_size) {
2041 dp->i_d.di_size = size;
2042 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
2043 }
2044 }
2045 return 0;
2046 done:
2047 xfs_da_binval(tp, dead_buf);
2048 return error;
2049 }
2050
2051 /*
2052 * See if the mapping(s) for this btree block are valid, i.e.
2053 * don't contain holes, are logically contiguous, and cover the whole range.
2054 */
2055 STATIC int
2056 xfs_da_map_covers_blocks(
2057 int nmap,
2058 xfs_bmbt_irec_t *mapp,
2059 xfs_dablk_t bno,
2060 int count)
2061 {
2062 int i;
2063 xfs_fileoff_t off;
2064
2065 for (i = 0, off = bno; i < nmap; i++) {
2066 if (mapp[i].br_startblock == HOLESTARTBLOCK ||
2067 mapp[i].br_startblock == DELAYSTARTBLOCK) {
2068 return 0;
2069 }
2070 if (off != mapp[i].br_startoff) {
2071 return 0;
2072 }
2073 off += mapp[i].br_blockcount;
2074 }
2075 return off == bno + count;
2076 }
2077
2078 /*
2079 * Make a dabuf.
2080 * Used for get_buf, read_buf, read_bufr, and reada_buf.
2081 */
2082 STATIC int
2083 xfs_da_do_buf(
2084 xfs_trans_t *trans,
2085 xfs_inode_t *dp,
2086 xfs_dablk_t bno,
2087 xfs_daddr_t *mappedbnop,
2088 xfs_dabuf_t **bpp,
2089 int whichfork,
2090 int caller,
2091 inst_t *ra)
2092 {
2093 xfs_buf_t *bp = NULL;
2094 xfs_buf_t **bplist;
2095 int error=0;
2096 int i;
2097 xfs_bmbt_irec_t map;
2098 xfs_bmbt_irec_t *mapp;
2099 xfs_daddr_t mappedbno;
2100 xfs_mount_t *mp;
2101 int nbplist=0;
2102 int nfsb;
2103 int nmap;
2104 xfs_dabuf_t *rbp;
2105
2106 mp = dp->i_mount;
2107 if (whichfork == XFS_DATA_FORK && XFS_DIR_IS_V2(mp))
2108 nfsb = mp->m_dirblkfsbs;
2109 else
2110 nfsb = 1;
2111 mappedbno = *mappedbnop;
2112 /*
2113 * Caller doesn't have a mapping. -2 means don't complain
2114 * if we land in a hole.
2115 */
2116 if (mappedbno == -1 || mappedbno == -2) {
2117 /*
2118 * Optimize the one-block case.
2119 */
2120 if (nfsb == 1) {
2121 xfs_fsblock_t fsb;
2122
2123 if ((error =
2124 xfs_bmapi_single(trans, dp, whichfork, &fsb,
2125 (xfs_fileoff_t)bno))) {
2126 return error;
2127 }
2128 mapp = &map;
2129 if (fsb == NULLFSBLOCK) {
2130 nmap = 0;
2131 } else {
2132 map.br_startblock = fsb;
2133 map.br_startoff = (xfs_fileoff_t)bno;
2134 map.br_blockcount = 1;
2135 nmap = 1;
2136 }
2137 } else {
2138 mapp = kmem_alloc(sizeof(*mapp) * nfsb, KM_SLEEP);
2139 nmap = nfsb;
2140 if ((error = xfs_bmapi(trans, dp, (xfs_fileoff_t)bno,
2141 nfsb,
2142 XFS_BMAPI_METADATA |
2143 XFS_BMAPI_AFLAG(whichfork),
2144 NULL, 0, mapp, &nmap, NULL)))
2145 goto exit0;
2146 }
2147 } else {
2148 map.br_startblock = XFS_DADDR_TO_FSB(mp, mappedbno);
2149 map.br_startoff = (xfs_fileoff_t)bno;
2150 map.br_blockcount = nfsb;
2151 mapp = &map;
2152 nmap = 1;
2153 }
2154 if (!xfs_da_map_covers_blocks(nmap, mapp, bno, nfsb)) {
2155 error = mappedbno == -2 ? 0 : XFS_ERROR(EFSCORRUPTED);
2156 if (unlikely(error == EFSCORRUPTED)) {
2157 if (xfs_error_level >= XFS_ERRLEVEL_LOW) {
2158 int i;
2159 cmn_err(CE_ALERT, "xfs_da_do_buf: bno %lld\n",
2160 (long long)bno);
2161 cmn_err(CE_ALERT, "dir: inode %lld\n",
2162 (long long)dp->i_ino);
2163 for (i = 0; i < nmap; i++) {
2164 cmn_err(CE_ALERT,
2165 "[%02d] br_startoff %lld br_startblock %lld br_blockcount %lld br_state %d\n",
2166 i,
2167 (long long)mapp[i].br_startoff,
2168 (long long)mapp[i].br_startblock,
2169 (long long)mapp[i].br_blockcount,
2170 mapp[i].br_state);
2171 }
2172 }
2173 XFS_ERROR_REPORT("xfs_da_do_buf(1)",
2174 XFS_ERRLEVEL_LOW, mp);
2175 }
2176 goto exit0;
2177 }
2178 if (caller != 3 && nmap > 1) {
2179 bplist = kmem_alloc(sizeof(*bplist) * nmap, KM_SLEEP);
2180 nbplist = 0;
2181 } else
2182 bplist = NULL;
2183 /*
2184 * Turn the mapping(s) into buffer(s).
2185 */
2186 for (i = 0; i < nmap; i++) {
2187 int nmapped;
2188
2189 mappedbno = XFS_FSB_TO_DADDR(mp, mapp[i].br_startblock);
2190 if (i == 0)
2191 *mappedbnop = mappedbno;
2192 nmapped = (int)XFS_FSB_TO_BB(mp, mapp[i].br_blockcount);
2193 switch (caller) {
2194 case 0:
2195 bp = xfs_trans_get_buf(trans, mp->m_ddev_targp,
2196 mappedbno, nmapped, 0);
2197 error = bp ? XFS_BUF_GETERROR(bp) : XFS_ERROR(EIO);
2198 break;
2199 case 1:
2200 #ifndef __KERNEL__
2201 case 2:
2202 #endif
2203 bp = NULL;
2204 error = xfs_trans_read_buf(mp, trans, mp->m_ddev_targp,
2205 mappedbno, nmapped, 0, &bp);
2206 break;
2207 #ifdef __KERNEL__
2208 case 3:
2209 xfs_baread(mp->m_ddev_targp, mappedbno, nmapped);
2210 error = 0;
2211 bp = NULL;
2212 break;
2213 #endif
2214 }
2215 if (error) {
2216 if (bp)
2217 xfs_trans_brelse(trans, bp);
2218 goto exit1;
2219 }
2220 if (!bp)
2221 continue;
2222 if (caller == 1) {
2223 if (whichfork == XFS_ATTR_FORK) {
2224 XFS_BUF_SET_VTYPE_REF(bp, B_FS_ATTR_BTREE,
2225 XFS_ATTR_BTREE_REF);
2226 } else {
2227 XFS_BUF_SET_VTYPE_REF(bp, B_FS_DIR_BTREE,
2228 XFS_DIR_BTREE_REF);
2229 }
2230 }
2231 if (bplist) {
2232 bplist[nbplist++] = bp;
2233 }
2234 }
2235 /*
2236 * Build a dabuf structure.
2237 */
2238 if (bplist) {
2239 rbp = xfs_da_buf_make(nbplist, bplist, ra);
2240 } else if (bp)
2241 rbp = xfs_da_buf_make(1, &bp, ra);
2242 else
2243 rbp = NULL;
2244 /*
2245 * For read_buf, check the magic number.
2246 */
2247 if (caller == 1) {
2248 xfs_dir2_data_t *data;
2249 xfs_dir2_free_t *free;
2250 xfs_da_blkinfo_t *info;
2251 uint magic, magic1;
2252
2253 info = rbp->data;
2254 data = rbp->data;
2255 free = rbp->data;
2256 magic = INT_GET(info->magic, ARCH_CONVERT);
2257 magic1 = INT_GET(data->hdr.magic, ARCH_CONVERT);
2258 if (unlikely(
2259 XFS_TEST_ERROR((magic != XFS_DA_NODE_MAGIC) &&
2260 (magic != XFS_DIR_LEAF_MAGIC) &&
2261 (magic != XFS_ATTR_LEAF_MAGIC) &&
2262 (magic != XFS_DIR2_LEAF1_MAGIC) &&
2263 (magic != XFS_DIR2_LEAFN_MAGIC) &&
2264 (magic1 != XFS_DIR2_BLOCK_MAGIC) &&
2265 (magic1 != XFS_DIR2_DATA_MAGIC) &&
2266 (INT_GET(free->hdr.magic, ARCH_CONVERT) != XFS_DIR2_FREE_MAGIC),
2267 mp, XFS_ERRTAG_DA_READ_BUF,
2268 XFS_RANDOM_DA_READ_BUF))) {
2269 xfs_buftrace("DA READ ERROR", rbp->bps[0]);
2270 XFS_CORRUPTION_ERROR("xfs_da_do_buf(2)",
2271 XFS_ERRLEVEL_LOW, mp, info);
2272 error = XFS_ERROR(EFSCORRUPTED);
2273 xfs_da_brelse(trans, rbp);
2274 nbplist = 0;
2275 goto exit1;
2276 }
2277 }
2278 if (bplist) {
2279 kmem_free(bplist, sizeof(*bplist) * nmap);
2280 }
2281 if (mapp != &map) {
2282 kmem_free(mapp, sizeof(*mapp) * nfsb);
2283 }
2284 if (bpp)
2285 *bpp = rbp;
2286 return 0;
2287 exit1:
2288 if (bplist) {
2289 for (i = 0; i < nbplist; i++)
2290 xfs_trans_brelse(trans, bplist[i]);
2291 kmem_free(bplist, sizeof(*bplist) * nmap);
2292 }
2293 exit0:
2294 if (mapp != &map)
2295 kmem_free(mapp, sizeof(*mapp) * nfsb);
2296 if (bpp)
2297 *bpp = NULL;
2298 return error;
2299 }
2300
2301 /*
2302 * Get a buffer for the dir/attr block.
2303 */
2304 int
2305 xfs_da_get_buf(
2306 xfs_trans_t *trans,
2307 xfs_inode_t *dp,
2308 xfs_dablk_t bno,
2309 xfs_daddr_t mappedbno,
2310 xfs_dabuf_t **bpp,
2311 int whichfork)
2312 {
2313 return xfs_da_do_buf(trans, dp, bno, &mappedbno, bpp, whichfork, 0,
2314 (inst_t *)__return_address);
2315 }
2316
2317 /*
2318 * Get a buffer for the dir/attr block, fill in the contents.
2319 */
2320 int
2321 xfs_da_read_buf(
2322 xfs_trans_t *trans,
2323 xfs_inode_t *dp,
2324 xfs_dablk_t bno,
2325 xfs_daddr_t mappedbno,
2326 xfs_dabuf_t **bpp,
2327 int whichfork)
2328 {
2329 return xfs_da_do_buf(trans, dp, bno, &mappedbno, bpp, whichfork, 1,
2330 (inst_t *)__return_address);
2331 }
2332
2333 /*
2334 * Readahead the dir/attr block.
2335 */
2336 xfs_daddr_t
2337 xfs_da_reada_buf(
2338 xfs_trans_t *trans,
2339 xfs_inode_t *dp,
2340 xfs_dablk_t bno,
2341 int whichfork)
2342 {
2343 xfs_daddr_t rval;
2344
2345 rval = -1;
2346 if (xfs_da_do_buf(trans, dp, bno, &rval, NULL, whichfork, 3,
2347 (inst_t *)__return_address))
2348 return -1;
2349 else
2350 return rval;
2351 }
2352
2353 /*
2354 * Calculate the number of bits needed to hold i different values.
2355 */
2356 uint
2357 xfs_da_log2_roundup(uint i)
2358 {
2359 uint rval;
2360
2361 for (rval = 0; rval < NBBY * sizeof(i); rval++) {
2362 if ((1 << rval) >= i)
2363 break;
2364 }
2365 return(rval);
2366 }
2367
2368 kmem_zone_t *xfs_da_state_zone; /* anchor for state struct zone */
2369 kmem_zone_t *xfs_dabuf_zone; /* dabuf zone */
2370
2371 /*
2372 * Allocate a dir-state structure.
2373 * We don't put them on the stack since they're large.
2374 */
2375 xfs_da_state_t *
2376 xfs_da_state_alloc(void)
2377 {
2378 return kmem_zone_zalloc(xfs_da_state_zone, KM_SLEEP);
2379 }
2380
2381 /*
2382 * Kill the altpath contents of a da-state structure.
2383 */
2384 void
2385 xfs_da_state_kill_altpath(xfs_da_state_t *state)
2386 {
2387 int i;
2388
2389 for (i = 0; i < state->altpath.active; i++) {
2390 if (state->altpath.blk[i].bp) {
2391 if (state->altpath.blk[i].bp != state->path.blk[i].bp)
2392 xfs_da_buf_done(state->altpath.blk[i].bp);
2393 state->altpath.blk[i].bp = NULL;
2394 }
2395 }
2396 state->altpath.active = 0;
2397 }
2398
2399 /*
2400 * Free a da-state structure.
2401 */
2402 void
2403 xfs_da_state_free(xfs_da_state_t *state)
2404 {
2405 int i;
2406
2407 xfs_da_state_kill_altpath(state);
2408 for (i = 0; i < state->path.active; i++) {
2409 if (state->path.blk[i].bp)
2410 xfs_da_buf_done(state->path.blk[i].bp);
2411 }
2412 if (state->extravalid && state->extrablk.bp)
2413 xfs_da_buf_done(state->extrablk.bp);
2414 #ifdef DEBUG
2415 memset((char *)state, 0, sizeof(*state));
2416 #endif /* DEBUG */
2417 kmem_zone_free(xfs_da_state_zone, state);
2418 }
2419
2420 #ifdef XFS_DABUF_DEBUG
2421 xfs_dabuf_t *xfs_dabuf_global_list;
2422 lock_t xfs_dabuf_global_lock;
2423 #endif
2424
2425 /*
2426 * Create a dabuf.
2427 */
2428 /* ARGSUSED */
2429 STATIC xfs_dabuf_t *
2430 xfs_da_buf_make(int nbuf, xfs_buf_t **bps, inst_t *ra)
2431 {
2432 xfs_buf_t *bp;
2433 xfs_dabuf_t *dabuf;
2434 int i;
2435 int off;
2436
2437 if (nbuf == 1)
2438 dabuf = kmem_zone_alloc(xfs_dabuf_zone, KM_SLEEP);
2439 else
2440 dabuf = kmem_alloc(XFS_DA_BUF_SIZE(nbuf), KM_SLEEP);
2441 dabuf->dirty = 0;
2442 #ifdef XFS_DABUF_DEBUG
2443 dabuf->ra = ra;
2444 dabuf->target = XFS_BUF_TARGET(bps[0]);
2445 dabuf->blkno = XFS_BUF_ADDR(bps[0]);
2446 #endif
2447 if (nbuf == 1) {
2448 dabuf->nbuf = 1;
2449 bp = bps[0];
2450 dabuf->bbcount = (short)BTOBB(XFS_BUF_COUNT(bp));
2451 dabuf->data = XFS_BUF_PTR(bp);
2452 dabuf->bps[0] = bp;
2453 } else {
2454 dabuf->nbuf = nbuf;
2455 for (i = 0, dabuf->bbcount = 0; i < nbuf; i++) {
2456 dabuf->bps[i] = bp = bps[i];
2457 dabuf->bbcount += BTOBB(XFS_BUF_COUNT(bp));
2458 }
2459 dabuf->data = kmem_alloc(BBTOB(dabuf->bbcount), KM_SLEEP);
2460 for (i = off = 0; i < nbuf; i++, off += XFS_BUF_COUNT(bp)) {
2461 bp = bps[i];
2462 memcpy((char *)dabuf->data + off, XFS_BUF_PTR(bp),
2463 XFS_BUF_COUNT(bp));
2464 }
2465 }
2466 #ifdef XFS_DABUF_DEBUG
2467 {
2468 SPLDECL(s);
2469 xfs_dabuf_t *p;
2470
2471 s = mutex_spinlock(&xfs_dabuf_global_lock);
2472 for (p = xfs_dabuf_global_list; p; p = p->next) {
2473 ASSERT(p->blkno != dabuf->blkno ||
2474 p->target != dabuf->target);
2475 }
2476 dabuf->prev = NULL;
2477 if (xfs_dabuf_global_list)
2478 xfs_dabuf_global_list->prev = dabuf;
2479 dabuf->next = xfs_dabuf_global_list;
2480 xfs_dabuf_global_list = dabuf;
2481 mutex_spinunlock(&xfs_dabuf_global_lock, s);
2482 }
2483 #endif
2484 return dabuf;
2485 }
2486
2487 /*
2488 * Un-dirty a dabuf.
2489 */
2490 STATIC void
2491 xfs_da_buf_clean(xfs_dabuf_t *dabuf)
2492 {
2493 xfs_buf_t *bp;
2494 int i;
2495 int off;
2496
2497 if (dabuf->dirty) {
2498 ASSERT(dabuf->nbuf > 1);
2499 dabuf->dirty = 0;
2500 for (i = off = 0; i < dabuf->nbuf;
2501 i++, off += XFS_BUF_COUNT(bp)) {
2502 bp = dabuf->bps[i];
2503 memcpy(XFS_BUF_PTR(bp), (char *)dabuf->data + off,
2504 XFS_BUF_COUNT(bp));
2505 }
2506 }
2507 }
2508
2509 /*
2510 * Release a dabuf.
2511 */
2512 void
2513 xfs_da_buf_done(xfs_dabuf_t *dabuf)
2514 {
2515 ASSERT(dabuf);
2516 ASSERT(dabuf->nbuf && dabuf->data && dabuf->bbcount && dabuf->bps[0]);
2517 if (dabuf->dirty)
2518 xfs_da_buf_clean(dabuf);
2519 if (dabuf->nbuf > 1)
2520 kmem_free(dabuf->data, BBTOB(dabuf->bbcount));
2521 #ifdef XFS_DABUF_DEBUG
2522 {
2523 SPLDECL(s);
2524
2525 s = mutex_spinlock(&xfs_dabuf_global_lock);
2526 if (dabuf->prev)
2527 dabuf->prev->next = dabuf->next;
2528 else
2529 xfs_dabuf_global_list = dabuf->next;
2530 if (dabuf->next)
2531 dabuf->next->prev = dabuf->prev;
2532 mutex_spinunlock(&xfs_dabuf_global_lock, s);
2533 }
2534 memset(dabuf, 0, XFS_DA_BUF_SIZE(dabuf->nbuf));
2535 #endif
2536 if (dabuf->nbuf == 1)
2537 kmem_zone_free(xfs_dabuf_zone, dabuf);
2538 else
2539 kmem_free(dabuf, XFS_DA_BUF_SIZE(dabuf->nbuf));
2540 }
2541
2542 /*
2543 * Log transaction from a dabuf.
2544 */
2545 void
2546 xfs_da_log_buf(xfs_trans_t *tp, xfs_dabuf_t *dabuf, uint first, uint last)
2547 {
2548 xfs_buf_t *bp;
2549 uint f;
2550 int i;
2551 uint l;
2552 int off;
2553
2554 ASSERT(dabuf->nbuf && dabuf->data && dabuf->bbcount && dabuf->bps[0]);
2555 if (dabuf->nbuf == 1) {
2556 ASSERT(dabuf->data == (void *)XFS_BUF_PTR(dabuf->bps[0]));
2557 xfs_trans_log_buf(tp, dabuf->bps[0], first, last);
2558 return;
2559 }
2560 dabuf->dirty = 1;
2561 ASSERT(first <= last);
2562 for (i = off = 0; i < dabuf->nbuf; i++, off += XFS_BUF_COUNT(bp)) {
2563 bp = dabuf->bps[i];
2564 f = off;
2565 l = f + XFS_BUF_COUNT(bp) - 1;
2566 if (f < first)
2567 f = first;
2568 if (l > last)
2569 l = last;
2570 if (f <= l)
2571 xfs_trans_log_buf(tp, bp, f - off, l - off);
2572 /*
2573 * B_DONE is set by xfs_trans_log buf.
2574 * If we don't set it on a new buffer (get not read)
2575 * then if we don't put anything in the buffer it won't
2576 * be set, and at commit it it released into the cache,
2577 * and then a read will fail.
2578 */
2579 else if (!(XFS_BUF_ISDONE(bp)))
2580 XFS_BUF_DONE(bp);
2581 }
2582 ASSERT(last < off);
2583 }
2584
2585 /*
2586 * Release dabuf from a transaction.
2587 * Have to free up the dabuf before the buffers are released,
2588 * since the synchronization on the dabuf is really the lock on the buffer.
2589 */
2590 void
2591 xfs_da_brelse(xfs_trans_t *tp, xfs_dabuf_t *dabuf)
2592 {
2593 xfs_buf_t *bp;
2594 xfs_buf_t **bplist;
2595 int i;
2596 int nbuf;
2597
2598 ASSERT(dabuf->nbuf && dabuf->data && dabuf->bbcount && dabuf->bps[0]);
2599 if ((nbuf = dabuf->nbuf) == 1) {
2600 bplist = &bp;
2601 bp = dabuf->bps[0];
2602 } else {
2603 bplist = kmem_alloc(nbuf * sizeof(*bplist), KM_SLEEP);
2604 memcpy(bplist, dabuf->bps, nbuf * sizeof(*bplist));
2605 }
2606 xfs_da_buf_done(dabuf);
2607 for (i = 0; i < nbuf; i++)
2608 xfs_trans_brelse(tp, bplist[i]);
2609 if (bplist != &bp)
2610 kmem_free(bplist, nbuf * sizeof(*bplist));
2611 }
2612
2613 /*
2614 * Invalidate dabuf from a transaction.
2615 */
2616 void
2617 xfs_da_binval(xfs_trans_t *tp, xfs_dabuf_t *dabuf)
2618 {
2619 xfs_buf_t *bp;
2620 xfs_buf_t **bplist;
2621 int i;
2622 int nbuf;
2623
2624 ASSERT(dabuf->nbuf && dabuf->data && dabuf->bbcount && dabuf->bps[0]);
2625 if ((nbuf = dabuf->nbuf) == 1) {
2626 bplist = &bp;
2627 bp = dabuf->bps[0];
2628 } else {
2629 bplist = kmem_alloc(nbuf * sizeof(*bplist), KM_SLEEP);
2630 memcpy(bplist, dabuf->bps, nbuf * sizeof(*bplist));
2631 }
2632 xfs_da_buf_done(dabuf);
2633 for (i = 0; i < nbuf; i++)
2634 xfs_trans_binval(tp, bplist[i]);
2635 if (bplist != &bp)
2636 kmem_free(bplist, nbuf * sizeof(*bplist));
2637 }
2638
2639 /*
2640 * Get the first daddr from a dabuf.
2641 */
2642 xfs_daddr_t
2643 xfs_da_blkno(xfs_dabuf_t *dabuf)
2644 {
2645 ASSERT(dabuf->nbuf);
2646 ASSERT(dabuf->data);
2647 return XFS_BUF_ADDR(dabuf->bps[0]);
2648 }