1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
4 * All Rights Reserved.
5 */
6 #include "xfs.h"
7 #include "xfs_fs.h"
8 #include "xfs_shared.h"
9 #include "xfs_format.h"
10 #include "xfs_log_format.h"
11 #include "xfs_trans_resv.h"
12 #include "xfs_bit.h"
13 #include "xfs_mount.h"
14 #include "xfs_inode.h"
15 #include "xfs_trans.h"
16 #include "xfs_alloc.h"
17 #include "xfs_btree.h"
18 #include "xfs_bmap_btree.h"
19 #include "xfs_bmap.h"
20 #include "xfs_error.h"
21 #include "xfs_quota.h"
22 #include "xfs_trace.h"
23 #include "xfs_rmap.h"
24
25 /*
26 * Convert on-disk form of btree root to in-memory form.
27 */
28 void
xfs_bmdr_to_bmbt(struct xfs_inode * ip,xfs_bmdr_block_t * dblock,int dblocklen,struct xfs_btree_block * rblock,int rblocklen)29 xfs_bmdr_to_bmbt(
30 struct xfs_inode *ip,
31 xfs_bmdr_block_t *dblock,
32 int dblocklen,
33 struct xfs_btree_block *rblock,
34 int rblocklen)
35 {
36 struct xfs_mount *mp = ip->i_mount;
37 int dmxr;
38 xfs_bmbt_key_t *fkp;
39 __be64 *fpp;
40 xfs_bmbt_key_t *tkp;
41 __be64 *tpp;
42
43 xfs_btree_init_block_int(mp, rblock, XFS_BUF_DADDR_NULL,
44 XFS_BTNUM_BMAP, 0, 0, ip->i_ino,
45 XFS_BTREE_LONG_PTRS);
46 rblock->bb_level = dblock->bb_level;
47 ASSERT(be16_to_cpu(rblock->bb_level) > 0);
48 rblock->bb_numrecs = dblock->bb_numrecs;
49 dmxr = xfs_bmdr_maxrecs(dblocklen, 0);
50 fkp = XFS_BMDR_KEY_ADDR(dblock, 1);
51 tkp = XFS_BMBT_KEY_ADDR(mp, rblock, 1);
52 fpp = XFS_BMDR_PTR_ADDR(dblock, 1, dmxr);
53 tpp = XFS_BMAP_BROOT_PTR_ADDR(mp, rblock, 1, rblocklen);
54 dmxr = be16_to_cpu(dblock->bb_numrecs);
55 memcpy(tkp, fkp, sizeof(*fkp) * dmxr);
56 memcpy(tpp, fpp, sizeof(*fpp) * dmxr);
57 }
58
59 void
xfs_bmbt_disk_get_all(struct xfs_bmbt_rec * rec,struct xfs_bmbt_irec * irec)60 xfs_bmbt_disk_get_all(
61 struct xfs_bmbt_rec *rec,
62 struct xfs_bmbt_irec *irec)
63 {
64 uint64_t l0 = get_unaligned_be64(&rec->l0);
65 uint64_t l1 = get_unaligned_be64(&rec->l1);
66
67 irec->br_startoff = (l0 & xfs_mask64lo(64 - BMBT_EXNTFLAG_BITLEN)) >> 9;
68 irec->br_startblock = ((l0 & xfs_mask64lo(9)) << 43) | (l1 >> 21);
69 irec->br_blockcount = l1 & xfs_mask64lo(21);
70 if (l0 >> (64 - BMBT_EXNTFLAG_BITLEN))
71 irec->br_state = XFS_EXT_UNWRITTEN;
72 else
73 irec->br_state = XFS_EXT_NORM;
74 }
75
76 /*
77 * Extract the blockcount field from an on disk bmap extent record.
78 */
79 xfs_filblks_t
xfs_bmbt_disk_get_blockcount(xfs_bmbt_rec_t * r)80 xfs_bmbt_disk_get_blockcount(
81 xfs_bmbt_rec_t *r)
82 {
83 return (xfs_filblks_t)(be64_to_cpu(r->l1) & xfs_mask64lo(21));
84 }
85
86 /*
87 * Extract the startoff field from a disk format bmap extent record.
88 */
89 xfs_fileoff_t
xfs_bmbt_disk_get_startoff(xfs_bmbt_rec_t * r)90 xfs_bmbt_disk_get_startoff(
91 xfs_bmbt_rec_t *r)
92 {
93 return ((xfs_fileoff_t)be64_to_cpu(r->l0) &
94 xfs_mask64lo(64 - BMBT_EXNTFLAG_BITLEN)) >> 9;
95 }
96
97 /*
98 * Set all the fields in a bmap extent record from the uncompressed form.
99 */
100 void
xfs_bmbt_disk_set_all(struct xfs_bmbt_rec * r,struct xfs_bmbt_irec * s)101 xfs_bmbt_disk_set_all(
102 struct xfs_bmbt_rec *r,
103 struct xfs_bmbt_irec *s)
104 {
105 int extent_flag = (s->br_state != XFS_EXT_NORM);
106
107 ASSERT(s->br_state == XFS_EXT_NORM || s->br_state == XFS_EXT_UNWRITTEN);
108 ASSERT(!(s->br_startoff & xfs_mask64hi(64-BMBT_STARTOFF_BITLEN)));
109 ASSERT(!(s->br_blockcount & xfs_mask64hi(64-BMBT_BLOCKCOUNT_BITLEN)));
110 ASSERT(!(s->br_startblock & xfs_mask64hi(64-BMBT_STARTBLOCK_BITLEN)));
111
112 put_unaligned_be64(
113 ((xfs_bmbt_rec_base_t)extent_flag << 63) |
114 ((xfs_bmbt_rec_base_t)s->br_startoff << 9) |
115 ((xfs_bmbt_rec_base_t)s->br_startblock >> 43), &r->l0);
116 put_unaligned_be64(
117 ((xfs_bmbt_rec_base_t)s->br_startblock << 21) |
118 ((xfs_bmbt_rec_base_t)s->br_blockcount &
119 (xfs_bmbt_rec_base_t)xfs_mask64lo(21)), &r->l1);
120 }
121
122 /*
123 * Convert in-memory form of btree root to on-disk form.
124 */
125 void
xfs_bmbt_to_bmdr(struct xfs_mount * mp,struct xfs_btree_block * rblock,int rblocklen,xfs_bmdr_block_t * dblock,int dblocklen)126 xfs_bmbt_to_bmdr(
127 struct xfs_mount *mp,
128 struct xfs_btree_block *rblock,
129 int rblocklen,
130 xfs_bmdr_block_t *dblock,
131 int dblocklen)
132 {
133 int dmxr;
134 xfs_bmbt_key_t *fkp;
135 __be64 *fpp;
136 xfs_bmbt_key_t *tkp;
137 __be64 *tpp;
138
139 if (xfs_sb_version_hascrc(&mp->m_sb)) {
140 ASSERT(rblock->bb_magic == cpu_to_be32(XFS_BMAP_CRC_MAGIC));
141 ASSERT(uuid_equal(&rblock->bb_u.l.bb_uuid,
142 &mp->m_sb.sb_meta_uuid));
143 ASSERT(rblock->bb_u.l.bb_blkno ==
144 cpu_to_be64(XFS_BUF_DADDR_NULL));
145 } else
146 ASSERT(rblock->bb_magic == cpu_to_be32(XFS_BMAP_MAGIC));
147 ASSERT(rblock->bb_u.l.bb_leftsib == cpu_to_be64(NULLFSBLOCK));
148 ASSERT(rblock->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK));
149 ASSERT(rblock->bb_level != 0);
150 dblock->bb_level = rblock->bb_level;
151 dblock->bb_numrecs = rblock->bb_numrecs;
152 dmxr = xfs_bmdr_maxrecs(dblocklen, 0);
153 fkp = XFS_BMBT_KEY_ADDR(mp, rblock, 1);
154 tkp = XFS_BMDR_KEY_ADDR(dblock, 1);
155 fpp = XFS_BMAP_BROOT_PTR_ADDR(mp, rblock, 1, rblocklen);
156 tpp = XFS_BMDR_PTR_ADDR(dblock, 1, dmxr);
157 dmxr = be16_to_cpu(dblock->bb_numrecs);
158 memcpy(tkp, fkp, sizeof(*fkp) * dmxr);
159 memcpy(tpp, fpp, sizeof(*fpp) * dmxr);
160 }
161
162 STATIC struct xfs_btree_cur *
xfs_bmbt_dup_cursor(struct xfs_btree_cur * cur)163 xfs_bmbt_dup_cursor(
164 struct xfs_btree_cur *cur)
165 {
166 struct xfs_btree_cur *new;
167
168 new = xfs_bmbt_init_cursor(cur->bc_mp, cur->bc_tp,
169 cur->bc_ino.ip, cur->bc_ino.whichfork);
170
171 /*
172 * Copy the firstblock, dfops, and flags values,
173 * since init cursor doesn't get them.
174 */
175 new->bc_ino.flags = cur->bc_ino.flags;
176
177 return new;
178 }
179
180 STATIC void
xfs_bmbt_update_cursor(struct xfs_btree_cur * src,struct xfs_btree_cur * dst)181 xfs_bmbt_update_cursor(
182 struct xfs_btree_cur *src,
183 struct xfs_btree_cur *dst)
184 {
185 ASSERT((dst->bc_tp->t_firstblock != NULLFSBLOCK) ||
186 (dst->bc_ino.ip->i_d.di_flags & XFS_DIFLAG_REALTIME));
187
188 dst->bc_ino.allocated += src->bc_ino.allocated;
189 dst->bc_tp->t_firstblock = src->bc_tp->t_firstblock;
190
191 src->bc_ino.allocated = 0;
192 }
193
194 STATIC int
xfs_bmbt_alloc_block(struct xfs_btree_cur * cur,union xfs_btree_ptr * start,union xfs_btree_ptr * new,int * stat)195 xfs_bmbt_alloc_block(
196 struct xfs_btree_cur *cur,
197 union xfs_btree_ptr *start,
198 union xfs_btree_ptr *new,
199 int *stat)
200 {
201 xfs_alloc_arg_t args; /* block allocation args */
202 int error; /* error return value */
203
204 memset(&args, 0, sizeof(args));
205 args.tp = cur->bc_tp;
206 args.mp = cur->bc_mp;
207 args.fsbno = cur->bc_tp->t_firstblock;
208 xfs_rmap_ino_bmbt_owner(&args.oinfo, cur->bc_ino.ip->i_ino,
209 cur->bc_ino.whichfork);
210
211 if (args.fsbno == NULLFSBLOCK) {
212 args.fsbno = be64_to_cpu(start->l);
213 args.type = XFS_ALLOCTYPE_START_BNO;
214 /*
215 * Make sure there is sufficient room left in the AG to
216 * complete a full tree split for an extent insert. If
217 * we are converting the middle part of an extent then
218 * we may need space for two tree splits.
219 *
220 * We are relying on the caller to make the correct block
221 * reservation for this operation to succeed. If the
222 * reservation amount is insufficient then we may fail a
223 * block allocation here and corrupt the filesystem.
224 */
225 args.minleft = args.tp->t_blk_res;
226 } else if (cur->bc_tp->t_flags & XFS_TRANS_LOWMODE) {
227 args.type = XFS_ALLOCTYPE_START_BNO;
228 } else {
229 args.type = XFS_ALLOCTYPE_NEAR_BNO;
230 }
231
232 args.minlen = args.maxlen = args.prod = 1;
233 args.wasdel = cur->bc_ino.flags & XFS_BTCUR_BMBT_WASDEL;
234 if (!args.wasdel && args.tp->t_blk_res == 0) {
235 error = -ENOSPC;
236 goto error0;
237 }
238 error = xfs_alloc_vextent(&args);
239 if (error)
240 goto error0;
241
242 if (args.fsbno == NULLFSBLOCK && args.minleft) {
243 /*
244 * Could not find an AG with enough free space to satisfy
245 * a full btree split. Try again and if
246 * successful activate the lowspace algorithm.
247 */
248 args.fsbno = 0;
249 args.type = XFS_ALLOCTYPE_FIRST_AG;
250 error = xfs_alloc_vextent(&args);
251 if (error)
252 goto error0;
253 cur->bc_tp->t_flags |= XFS_TRANS_LOWMODE;
254 }
255 if (WARN_ON_ONCE(args.fsbno == NULLFSBLOCK)) {
256 *stat = 0;
257 return 0;
258 }
259
260 ASSERT(args.len == 1);
261 cur->bc_tp->t_firstblock = args.fsbno;
262 cur->bc_ino.allocated++;
263 cur->bc_ino.ip->i_d.di_nblocks++;
264 xfs_trans_log_inode(args.tp, cur->bc_ino.ip, XFS_ILOG_CORE);
265 xfs_trans_mod_dquot_byino(args.tp, cur->bc_ino.ip,
266 XFS_TRANS_DQ_BCOUNT, 1L);
267
268 new->l = cpu_to_be64(args.fsbno);
269
270 *stat = 1;
271 return 0;
272
273 error0:
274 return error;
275 }
276
277 STATIC int
xfs_bmbt_free_block(struct xfs_btree_cur * cur,struct xfs_buf * bp)278 xfs_bmbt_free_block(
279 struct xfs_btree_cur *cur,
280 struct xfs_buf *bp)
281 {
282 struct xfs_mount *mp = cur->bc_mp;
283 struct xfs_inode *ip = cur->bc_ino.ip;
284 struct xfs_trans *tp = cur->bc_tp;
285 xfs_fsblock_t fsbno = XFS_DADDR_TO_FSB(mp, XFS_BUF_ADDR(bp));
286 struct xfs_owner_info oinfo;
287
288 xfs_rmap_ino_bmbt_owner(&oinfo, ip->i_ino, cur->bc_ino.whichfork);
289 xfs_bmap_add_free(cur->bc_tp, fsbno, 1, &oinfo);
290 ip->i_d.di_nblocks--;
291
292 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
293 xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, -1L);
294 return 0;
295 }
296
297 STATIC int
xfs_bmbt_get_minrecs(struct xfs_btree_cur * cur,int level)298 xfs_bmbt_get_minrecs(
299 struct xfs_btree_cur *cur,
300 int level)
301 {
302 if (level == cur->bc_nlevels - 1) {
303 struct xfs_ifork *ifp;
304
305 ifp = XFS_IFORK_PTR(cur->bc_ino.ip,
306 cur->bc_ino.whichfork);
307
308 return xfs_bmbt_maxrecs(cur->bc_mp,
309 ifp->if_broot_bytes, level == 0) / 2;
310 }
311
312 return cur->bc_mp->m_bmap_dmnr[level != 0];
313 }
314
315 int
xfs_bmbt_get_maxrecs(struct xfs_btree_cur * cur,int level)316 xfs_bmbt_get_maxrecs(
317 struct xfs_btree_cur *cur,
318 int level)
319 {
320 if (level == cur->bc_nlevels - 1) {
321 struct xfs_ifork *ifp;
322
323 ifp = XFS_IFORK_PTR(cur->bc_ino.ip,
324 cur->bc_ino.whichfork);
325
326 return xfs_bmbt_maxrecs(cur->bc_mp,
327 ifp->if_broot_bytes, level == 0);
328 }
329
330 return cur->bc_mp->m_bmap_dmxr[level != 0];
331
332 }
333
334 /*
335 * Get the maximum records we could store in the on-disk format.
336 *
337 * For non-root nodes this is equivalent to xfs_bmbt_get_maxrecs, but
338 * for the root node this checks the available space in the dinode fork
339 * so that we can resize the in-memory buffer to match it. After a
340 * resize to the maximum size this function returns the same value
341 * as xfs_bmbt_get_maxrecs for the root node, too.
342 */
343 STATIC int
xfs_bmbt_get_dmaxrecs(struct xfs_btree_cur * cur,int level)344 xfs_bmbt_get_dmaxrecs(
345 struct xfs_btree_cur *cur,
346 int level)
347 {
348 if (level != cur->bc_nlevels - 1)
349 return cur->bc_mp->m_bmap_dmxr[level != 0];
350 return xfs_bmdr_maxrecs(cur->bc_ino.forksize, level == 0);
351 }
352
353 STATIC void
xfs_bmbt_init_key_from_rec(union xfs_btree_key * key,union xfs_btree_rec * rec)354 xfs_bmbt_init_key_from_rec(
355 union xfs_btree_key *key,
356 union xfs_btree_rec *rec)
357 {
358 key->bmbt.br_startoff =
359 cpu_to_be64(xfs_bmbt_disk_get_startoff(&rec->bmbt));
360 }
361
362 STATIC void
xfs_bmbt_init_high_key_from_rec(union xfs_btree_key * key,union xfs_btree_rec * rec)363 xfs_bmbt_init_high_key_from_rec(
364 union xfs_btree_key *key,
365 union xfs_btree_rec *rec)
366 {
367 key->bmbt.br_startoff = cpu_to_be64(
368 xfs_bmbt_disk_get_startoff(&rec->bmbt) +
369 xfs_bmbt_disk_get_blockcount(&rec->bmbt) - 1);
370 }
371
372 STATIC void
xfs_bmbt_init_rec_from_cur(struct xfs_btree_cur * cur,union xfs_btree_rec * rec)373 xfs_bmbt_init_rec_from_cur(
374 struct xfs_btree_cur *cur,
375 union xfs_btree_rec *rec)
376 {
377 xfs_bmbt_disk_set_all(&rec->bmbt, &cur->bc_rec.b);
378 }
379
380 STATIC void
xfs_bmbt_init_ptr_from_cur(struct xfs_btree_cur * cur,union xfs_btree_ptr * ptr)381 xfs_bmbt_init_ptr_from_cur(
382 struct xfs_btree_cur *cur,
383 union xfs_btree_ptr *ptr)
384 {
385 ptr->l = 0;
386 }
387
388 STATIC int64_t
xfs_bmbt_key_diff(struct xfs_btree_cur * cur,union xfs_btree_key * key)389 xfs_bmbt_key_diff(
390 struct xfs_btree_cur *cur,
391 union xfs_btree_key *key)
392 {
393 return (int64_t)be64_to_cpu(key->bmbt.br_startoff) -
394 cur->bc_rec.b.br_startoff;
395 }
396
397 STATIC int64_t
xfs_bmbt_diff_two_keys(struct xfs_btree_cur * cur,union xfs_btree_key * k1,union xfs_btree_key * k2)398 xfs_bmbt_diff_two_keys(
399 struct xfs_btree_cur *cur,
400 union xfs_btree_key *k1,
401 union xfs_btree_key *k2)
402 {
403 uint64_t a = be64_to_cpu(k1->bmbt.br_startoff);
404 uint64_t b = be64_to_cpu(k2->bmbt.br_startoff);
405
406 /*
407 * Note: This routine previously casted a and b to int64 and subtracted
408 * them to generate a result. This lead to problems if b was the
409 * "maximum" key value (all ones) being signed incorrectly, hence this
410 * somewhat less efficient version.
411 */
412 if (a > b)
413 return 1;
414 if (b > a)
415 return -1;
416 return 0;
417 }
418
419 static xfs_failaddr_t
xfs_bmbt_verify(struct xfs_buf * bp)420 xfs_bmbt_verify(
421 struct xfs_buf *bp)
422 {
423 struct xfs_mount *mp = bp->b_mount;
424 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
425 xfs_failaddr_t fa;
426 unsigned int level;
427
428 if (!xfs_verify_magic(bp, block->bb_magic))
429 return __this_address;
430
431 if (xfs_sb_version_hascrc(&mp->m_sb)) {
432 /*
433 * XXX: need a better way of verifying the owner here. Right now
434 * just make sure there has been one set.
435 */
436 fa = xfs_btree_lblock_v5hdr_verify(bp, XFS_RMAP_OWN_UNKNOWN);
437 if (fa)
438 return fa;
439 }
440
441 /*
442 * numrecs and level verification.
443 *
444 * We don't know what fork we belong to, so just verify that the level
445 * is less than the maximum of the two. Later checks will be more
446 * precise.
447 */
448 level = be16_to_cpu(block->bb_level);
449 if (level > max(mp->m_bm_maxlevels[0], mp->m_bm_maxlevels[1]))
450 return __this_address;
451
452 return xfs_btree_lblock_verify(bp, mp->m_bmap_dmxr[level != 0]);
453 }
454
455 static void
xfs_bmbt_read_verify(struct xfs_buf * bp)456 xfs_bmbt_read_verify(
457 struct xfs_buf *bp)
458 {
459 xfs_failaddr_t fa;
460
461 if (!xfs_btree_lblock_verify_crc(bp))
462 xfs_verifier_error(bp, -EFSBADCRC, __this_address);
463 else {
464 fa = xfs_bmbt_verify(bp);
465 if (fa)
466 xfs_verifier_error(bp, -EFSCORRUPTED, fa);
467 }
468
469 if (bp->b_error)
470 trace_xfs_btree_corrupt(bp, _RET_IP_);
471 }
472
473 static void
xfs_bmbt_write_verify(struct xfs_buf * bp)474 xfs_bmbt_write_verify(
475 struct xfs_buf *bp)
476 {
477 xfs_failaddr_t fa;
478
479 fa = xfs_bmbt_verify(bp);
480 if (fa) {
481 trace_xfs_btree_corrupt(bp, _RET_IP_);
482 xfs_verifier_error(bp, -EFSCORRUPTED, fa);
483 return;
484 }
485 xfs_btree_lblock_calc_crc(bp);
486 }
487
488 const struct xfs_buf_ops xfs_bmbt_buf_ops = {
489 .name = "xfs_bmbt",
490 .magic = { cpu_to_be32(XFS_BMAP_MAGIC),
491 cpu_to_be32(XFS_BMAP_CRC_MAGIC) },
492 .verify_read = xfs_bmbt_read_verify,
493 .verify_write = xfs_bmbt_write_verify,
494 .verify_struct = xfs_bmbt_verify,
495 };
496
497
498 STATIC int
xfs_bmbt_keys_inorder(struct xfs_btree_cur * cur,union xfs_btree_key * k1,union xfs_btree_key * k2)499 xfs_bmbt_keys_inorder(
500 struct xfs_btree_cur *cur,
501 union xfs_btree_key *k1,
502 union xfs_btree_key *k2)
503 {
504 return be64_to_cpu(k1->bmbt.br_startoff) <
505 be64_to_cpu(k2->bmbt.br_startoff);
506 }
507
508 STATIC int
xfs_bmbt_recs_inorder(struct xfs_btree_cur * cur,union xfs_btree_rec * r1,union xfs_btree_rec * r2)509 xfs_bmbt_recs_inorder(
510 struct xfs_btree_cur *cur,
511 union xfs_btree_rec *r1,
512 union xfs_btree_rec *r2)
513 {
514 return xfs_bmbt_disk_get_startoff(&r1->bmbt) +
515 xfs_bmbt_disk_get_blockcount(&r1->bmbt) <=
516 xfs_bmbt_disk_get_startoff(&r2->bmbt);
517 }
518
519 static const struct xfs_btree_ops xfs_bmbt_ops = {
520 .rec_len = sizeof(xfs_bmbt_rec_t),
521 .key_len = sizeof(xfs_bmbt_key_t),
522
523 .dup_cursor = xfs_bmbt_dup_cursor,
524 .update_cursor = xfs_bmbt_update_cursor,
525 .alloc_block = xfs_bmbt_alloc_block,
526 .free_block = xfs_bmbt_free_block,
527 .get_maxrecs = xfs_bmbt_get_maxrecs,
528 .get_minrecs = xfs_bmbt_get_minrecs,
529 .get_dmaxrecs = xfs_bmbt_get_dmaxrecs,
530 .init_key_from_rec = xfs_bmbt_init_key_from_rec,
531 .init_high_key_from_rec = xfs_bmbt_init_high_key_from_rec,
532 .init_rec_from_cur = xfs_bmbt_init_rec_from_cur,
533 .init_ptr_from_cur = xfs_bmbt_init_ptr_from_cur,
534 .key_diff = xfs_bmbt_key_diff,
535 .diff_two_keys = xfs_bmbt_diff_two_keys,
536 .buf_ops = &xfs_bmbt_buf_ops,
537 .keys_inorder = xfs_bmbt_keys_inorder,
538 .recs_inorder = xfs_bmbt_recs_inorder,
539 };
540
541 /*
542 * Allocate a new bmap btree cursor.
543 */
544 struct xfs_btree_cur * /* new bmap btree cursor */
xfs_bmbt_init_cursor(struct xfs_mount * mp,struct xfs_trans * tp,struct xfs_inode * ip,int whichfork)545 xfs_bmbt_init_cursor(
546 struct xfs_mount *mp, /* file system mount point */
547 struct xfs_trans *tp, /* transaction pointer */
548 struct xfs_inode *ip, /* inode owning the btree */
549 int whichfork) /* data or attr fork */
550 {
551 struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork);
552 struct xfs_btree_cur *cur;
553 ASSERT(whichfork != XFS_COW_FORK);
554
555 cur = kmem_cache_zalloc(xfs_btree_cur_zone, GFP_NOFS | __GFP_NOFAIL);
556
557 cur->bc_tp = tp;
558 cur->bc_mp = mp;
559 cur->bc_nlevels = be16_to_cpu(ifp->if_broot->bb_level) + 1;
560 cur->bc_btnum = XFS_BTNUM_BMAP;
561 cur->bc_blocklog = mp->m_sb.sb_blocklog;
562 cur->bc_statoff = XFS_STATS_CALC_INDEX(xs_bmbt_2);
563
564 cur->bc_ops = &xfs_bmbt_ops;
565 cur->bc_flags = XFS_BTREE_LONG_PTRS | XFS_BTREE_ROOT_IN_INODE;
566 if (xfs_sb_version_hascrc(&mp->m_sb))
567 cur->bc_flags |= XFS_BTREE_CRC_BLOCKS;
568
569 cur->bc_ino.forksize = XFS_IFORK_SIZE(ip, whichfork);
570 cur->bc_ino.ip = ip;
571 cur->bc_ino.allocated = 0;
572 cur->bc_ino.flags = 0;
573 cur->bc_ino.whichfork = whichfork;
574
575 return cur;
576 }
577
578 /*
579 * Calculate number of records in a bmap btree block.
580 */
581 int
xfs_bmbt_maxrecs(struct xfs_mount * mp,int blocklen,int leaf)582 xfs_bmbt_maxrecs(
583 struct xfs_mount *mp,
584 int blocklen,
585 int leaf)
586 {
587 blocklen -= XFS_BMBT_BLOCK_LEN(mp);
588
589 if (leaf)
590 return blocklen / sizeof(xfs_bmbt_rec_t);
591 return blocklen / (sizeof(xfs_bmbt_key_t) + sizeof(xfs_bmbt_ptr_t));
592 }
593
594 /*
595 * Calculate number of records in a bmap btree inode root.
596 */
597 int
xfs_bmdr_maxrecs(int blocklen,int leaf)598 xfs_bmdr_maxrecs(
599 int blocklen,
600 int leaf)
601 {
602 blocklen -= sizeof(xfs_bmdr_block_t);
603
604 if (leaf)
605 return blocklen / sizeof(xfs_bmdr_rec_t);
606 return blocklen / (sizeof(xfs_bmdr_key_t) + sizeof(xfs_bmdr_ptr_t));
607 }
608
609 /*
610 * Change the owner of a btree format fork fo the inode passed in. Change it to
611 * the owner of that is passed in so that we can change owners before or after
612 * we switch forks between inodes. The operation that the caller is doing will
613 * determine whether is needs to change owner before or after the switch.
614 *
615 * For demand paged transactional modification, the fork switch should be done
616 * after reading in all the blocks, modifying them and pinning them in the
617 * transaction. For modification when the buffers are already pinned in memory,
618 * the fork switch can be done before changing the owner as we won't need to
619 * validate the owner until the btree buffers are unpinned and writes can occur
620 * again.
621 *
622 * For recovery based ownership change, there is no transactional context and
623 * so a buffer list must be supplied so that we can record the buffers that we
624 * modified for the caller to issue IO on.
625 */
626 int
xfs_bmbt_change_owner(struct xfs_trans * tp,struct xfs_inode * ip,int whichfork,xfs_ino_t new_owner,struct list_head * buffer_list)627 xfs_bmbt_change_owner(
628 struct xfs_trans *tp,
629 struct xfs_inode *ip,
630 int whichfork,
631 xfs_ino_t new_owner,
632 struct list_head *buffer_list)
633 {
634 struct xfs_btree_cur *cur;
635 int error;
636
637 ASSERT(tp || buffer_list);
638 ASSERT(!(tp && buffer_list));
639 ASSERT(XFS_IFORK_PTR(ip, whichfork)->if_format == XFS_DINODE_FMT_BTREE);
640
641 cur = xfs_bmbt_init_cursor(ip->i_mount, tp, ip, whichfork);
642 if (!cur)
643 return -ENOMEM;
644 cur->bc_ino.flags |= XFS_BTCUR_BMBT_INVALID_OWNER;
645
646 error = xfs_btree_change_owner(cur, new_owner, buffer_list);
647 xfs_btree_del_cursor(cur, error);
648 return error;
649 }
650
651 /* Calculate the bmap btree size for some records. */
652 unsigned long long
xfs_bmbt_calc_size(struct xfs_mount * mp,unsigned long long len)653 xfs_bmbt_calc_size(
654 struct xfs_mount *mp,
655 unsigned long long len)
656 {
657 return xfs_btree_calc_size(mp->m_bmap_dmnr, len);
658 }
659