projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
xfs: factor out free space extent length check
[deliverable/linux.git] / fs / xfs / libxfs / xfs_attr_remote.c
1 /*
2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3 * Copyright (c) 2013 Red Hat, Inc.
4 * All Rights Reserved.
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it would be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 */
19 #include "xfs.h"
20 #include "xfs_fs.h"
21 #include "xfs_shared.h"
22 #include "xfs_format.h"
23 #include "xfs_log_format.h"
24 #include "xfs_trans_resv.h"
25 #include "xfs_bit.h"
26 #include "xfs_mount.h"
27 #include "xfs_da_format.h"
28 #include "xfs_da_btree.h"
29 #include "xfs_inode.h"
30 #include "xfs_alloc.h"
31 #include "xfs_trans.h"
32 #include "xfs_inode_item.h"
33 #include "xfs_bmap.h"
34 #include "xfs_bmap_util.h"
35 #include "xfs_attr.h"
36 #include "xfs_attr_leaf.h"
37 #include "xfs_attr_remote.h"
38 #include "xfs_trans_space.h"
39 #include "xfs_trace.h"
40 #include "xfs_cksum.h"
41 #include "xfs_buf_item.h"
42 #include "xfs_error.h"
43
44 #define ATTR_RMTVALUE_MAPSIZE 1 /* # of map entries at once */
45
46 /*
47 * Each contiguous block has a header, so it is not just a simple attribute
48 * length to FSB conversion.
49 */
50 int
51 xfs_attr3_rmt_blocks(
52 struct xfs_mount *mp,
53 int attrlen)
54 {
55 if (xfs_sb_version_hascrc(&mp->m_sb)) {
56 int buflen = XFS_ATTR3_RMT_BUF_SPACE(mp, mp->m_sb.sb_blocksize);
57 return (attrlen + buflen - 1) / buflen;
58 }
59 return XFS_B_TO_FSB(mp, attrlen);
60 }
61
62 /*
63 * Checking of the remote attribute header is split into two parts. The verifier
64 * does CRC, location and bounds checking, the unpacking function checks the
65 * attribute parameters and owner.
66 */
67 static bool
68 xfs_attr3_rmt_hdr_ok(
69 void *ptr,
70 xfs_ino_t ino,
71 uint32_t offset,
72 uint32_t size,
73 xfs_daddr_t bno)
74 {
75 struct xfs_attr3_rmt_hdr *rmt = ptr;
76
77 if (bno != be64_to_cpu(rmt->rm_blkno))
78 return false;
79 if (offset != be32_to_cpu(rmt->rm_offset))
80 return false;
81 if (size != be32_to_cpu(rmt->rm_bytes))
82 return false;
83 if (ino != be64_to_cpu(rmt->rm_owner))
84 return false;
85
86 /* ok */
87 return true;
88 }
89
90 static bool
91 xfs_attr3_rmt_verify(
92 struct xfs_mount *mp,
93 void *ptr,
94 int fsbsize,
95 xfs_daddr_t bno)
96 {
97 struct xfs_attr3_rmt_hdr *rmt = ptr;
98
99 if (!xfs_sb_version_hascrc(&mp->m_sb))
100 return false;
101 if (rmt->rm_magic != cpu_to_be32(XFS_ATTR3_RMT_MAGIC))
102 return false;
103 if (!uuid_equal(&rmt->rm_uuid, &mp->m_sb.sb_uuid))
104 return false;
105 if (be64_to_cpu(rmt->rm_blkno) != bno)
106 return false;
107 if (be32_to_cpu(rmt->rm_bytes) > fsbsize - sizeof(*rmt))
108 return false;
109 if (be32_to_cpu(rmt->rm_offset) +
110 be32_to_cpu(rmt->rm_bytes) > XATTR_SIZE_MAX)
111 return false;
112 if (rmt->rm_owner == 0)
113 return false;
114
115 return true;
116 }
117
118 static void
119 xfs_attr3_rmt_read_verify(
120 struct xfs_buf *bp)
121 {
122 struct xfs_mount *mp = bp->b_target->bt_mount;
123 char *ptr;
124 int len;
125 xfs_daddr_t bno;
126 int blksize = mp->m_attr_geo->blksize;
127
128 /* no verification of non-crc buffers */
129 if (!xfs_sb_version_hascrc(&mp->m_sb))
130 return;
131
132 ptr = bp->b_addr;
133 bno = bp->b_bn;
134 len = BBTOB(bp->b_length);
135 ASSERT(len >= blksize);
136
137 while (len > 0) {
138 if (!xfs_verify_cksum(ptr, blksize, XFS_ATTR3_RMT_CRC_OFF)) {
139 xfs_buf_ioerror(bp, -EFSBADCRC);
140 break;
141 }
142 if (!xfs_attr3_rmt_verify(mp, ptr, blksize, bno)) {
143 xfs_buf_ioerror(bp, -EFSCORRUPTED);
144 break;
145 }
146 len -= blksize;
147 ptr += blksize;
148 bno += BTOBB(blksize);
149 }
150
151 if (bp->b_error)
152 xfs_verifier_error(bp);
153 else
154 ASSERT(len == 0);
155 }
156
157 static void
158 xfs_attr3_rmt_write_verify(
159 struct xfs_buf *bp)
160 {
161 struct xfs_mount *mp = bp->b_target->bt_mount;
162 struct xfs_buf_log_item *bip = bp->b_fspriv;
163 char *ptr;
164 int len;
165 xfs_daddr_t bno;
166 int blksize = mp->m_attr_geo->blksize;
167
168 /* no verification of non-crc buffers */
169 if (!xfs_sb_version_hascrc(&mp->m_sb))
170 return;
171
172 ptr = bp->b_addr;
173 bno = bp->b_bn;
174 len = BBTOB(bp->b_length);
175 ASSERT(len >= blksize);
176
177 while (len > 0) {
178 if (!xfs_attr3_rmt_verify(mp, ptr, blksize, bno)) {
179 xfs_buf_ioerror(bp, -EFSCORRUPTED);
180 xfs_verifier_error(bp);
181 return;
182 }
183 if (bip) {
184 struct xfs_attr3_rmt_hdr *rmt;
185
186 rmt = (struct xfs_attr3_rmt_hdr *)ptr;
187 rmt->rm_lsn = cpu_to_be64(bip->bli_item.li_lsn);
188 }
189 xfs_update_cksum(ptr, blksize, XFS_ATTR3_RMT_CRC_OFF);
190
191 len -= blksize;
192 ptr += blksize;
193 bno += BTOBB(blksize);
194 }
195 ASSERT(len == 0);
196 }
197
198 const struct xfs_buf_ops xfs_attr3_rmt_buf_ops = {
199 .verify_read = xfs_attr3_rmt_read_verify,
200 .verify_write = xfs_attr3_rmt_write_verify,
201 };
202
203 STATIC int
204 xfs_attr3_rmt_hdr_set(
205 struct xfs_mount *mp,
206 void *ptr,
207 xfs_ino_t ino,
208 uint32_t offset,
209 uint32_t size,
210 xfs_daddr_t bno)
211 {
212 struct xfs_attr3_rmt_hdr *rmt = ptr;
213
214 if (!xfs_sb_version_hascrc(&mp->m_sb))
215 return 0;
216
217 rmt->rm_magic = cpu_to_be32(XFS_ATTR3_RMT_MAGIC);
218 rmt->rm_offset = cpu_to_be32(offset);
219 rmt->rm_bytes = cpu_to_be32(size);
220 uuid_copy(&rmt->rm_uuid, &mp->m_sb.sb_uuid);
221 rmt->rm_owner = cpu_to_be64(ino);
222 rmt->rm_blkno = cpu_to_be64(bno);
223
224 return sizeof(struct xfs_attr3_rmt_hdr);
225 }
226
227 /*
228 * Helper functions to copy attribute data in and out of the one disk extents
229 */
230 STATIC int
231 xfs_attr_rmtval_copyout(
232 struct xfs_mount *mp,
233 struct xfs_buf *bp,
234 xfs_ino_t ino,
235 int *offset,
236 int *valuelen,
237 __uint8_t **dst)
238 {
239 char *src = bp->b_addr;
240 xfs_daddr_t bno = bp->b_bn;
241 int len = BBTOB(bp->b_length);
242 int blksize = mp->m_attr_geo->blksize;
243
244 ASSERT(len >= blksize);
245
246 while (len > 0 && *valuelen > 0) {
247 int hdr_size = 0;
248 int byte_cnt = XFS_ATTR3_RMT_BUF_SPACE(mp, blksize);
249
250 byte_cnt = min(*valuelen, byte_cnt);
251
252 if (xfs_sb_version_hascrc(&mp->m_sb)) {
253 if (!xfs_attr3_rmt_hdr_ok(src, ino, *offset,
254 byte_cnt, bno)) {
255 xfs_alert(mp,
256 "remote attribute header mismatch bno/off/len/owner (0x%llx/0x%x/Ox%x/0x%llx)",
257 bno, *offset, byte_cnt, ino);
258 return -EFSCORRUPTED;
259 }
260 hdr_size = sizeof(struct xfs_attr3_rmt_hdr);
261 }
262
263 memcpy(*dst, src + hdr_size, byte_cnt);
264
265 /* roll buffer forwards */
266 len -= blksize;
267 src += blksize;
268 bno += BTOBB(blksize);
269
270 /* roll attribute data forwards */
271 *valuelen -= byte_cnt;
272 *dst += byte_cnt;
273 *offset += byte_cnt;
274 }
275 return 0;
276 }
277
278 STATIC void
279 xfs_attr_rmtval_copyin(
280 struct xfs_mount *mp,
281 struct xfs_buf *bp,
282 xfs_ino_t ino,
283 int *offset,
284 int *valuelen,
285 __uint8_t **src)
286 {
287 char *dst = bp->b_addr;
288 xfs_daddr_t bno = bp->b_bn;
289 int len = BBTOB(bp->b_length);
290 int blksize = mp->m_attr_geo->blksize;
291
292 ASSERT(len >= blksize);
293
294 while (len > 0 && *valuelen > 0) {
295 int hdr_size;
296 int byte_cnt = XFS_ATTR3_RMT_BUF_SPACE(mp, blksize);
297
298 byte_cnt = min(*valuelen, byte_cnt);
299 hdr_size = xfs_attr3_rmt_hdr_set(mp, dst, ino, *offset,
300 byte_cnt, bno);
301
302 memcpy(dst + hdr_size, *src, byte_cnt);
303
304 /*
305 * If this is the last block, zero the remainder of it.
306 * Check that we are actually the last block, too.
307 */
308 if (byte_cnt + hdr_size < blksize) {
309 ASSERT(*valuelen - byte_cnt == 0);
310 ASSERT(len == blksize);
311 memset(dst + hdr_size + byte_cnt, 0,
312 blksize - hdr_size - byte_cnt);
313 }
314
315 /* roll buffer forwards */
316 len -= blksize;
317 dst += blksize;
318 bno += BTOBB(blksize);
319
320 /* roll attribute data forwards */
321 *valuelen -= byte_cnt;
322 *src += byte_cnt;
323 *offset += byte_cnt;
324 }
325 }
326
327 /*
328 * Read the value associated with an attribute from the out-of-line buffer
329 * that we stored it in.
330 */
331 int
332 xfs_attr_rmtval_get(
333 struct xfs_da_args *args)
334 {
335 struct xfs_bmbt_irec map[ATTR_RMTVALUE_MAPSIZE];
336 struct xfs_mount *mp = args->dp->i_mount;
337 struct xfs_buf *bp;
338 xfs_dablk_t lblkno = args->rmtblkno;
339 __uint8_t *dst = args->value;
340 int valuelen;
341 int nmap;
342 int error;
343 int blkcnt = args->rmtblkcnt;
344 int i;
345 int offset = 0;
346
347 trace_xfs_attr_rmtval_get(args);
348
349 ASSERT(!(args->flags & ATTR_KERNOVAL));
350 ASSERT(args->rmtvaluelen == args->valuelen);
351
352 valuelen = args->rmtvaluelen;
353 while (valuelen > 0) {
354 nmap = ATTR_RMTVALUE_MAPSIZE;
355 error = xfs_bmapi_read(args->dp, (xfs_fileoff_t)lblkno,
356 blkcnt, map, &nmap,
357 XFS_BMAPI_ATTRFORK);
358 if (error)
359 return error;
360 ASSERT(nmap >= 1);
361
362 for (i = 0; (i < nmap) && (valuelen > 0); i++) {
363 xfs_daddr_t dblkno;
364 int dblkcnt;
365
366 ASSERT((map[i].br_startblock != DELAYSTARTBLOCK) &&
367 (map[i].br_startblock != HOLESTARTBLOCK));
368 dblkno = XFS_FSB_TO_DADDR(mp, map[i].br_startblock);
369 dblkcnt = XFS_FSB_TO_BB(mp, map[i].br_blockcount);
370 error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp,
371 dblkno, dblkcnt, 0, &bp,
372 &xfs_attr3_rmt_buf_ops);
373 if (error)
374 return error;
375
376 error = xfs_attr_rmtval_copyout(mp, bp, args->dp->i_ino,
377 &offset, &valuelen,
378 &dst);
379 xfs_buf_relse(bp);
380 if (error)
381 return error;
382
383 /* roll attribute extent map forwards */
384 lblkno += map[i].br_blockcount;
385 blkcnt -= map[i].br_blockcount;
386 }
387 }
388 ASSERT(valuelen == 0);
389 return 0;
390 }
391
392 /*
393 * Write the value associated with an attribute into the out-of-line buffer
394 * that we have defined for it.
395 */
396 int
397 xfs_attr_rmtval_set(
398 struct xfs_da_args *args)
399 {
400 struct xfs_inode *dp = args->dp;
401 struct xfs_mount *mp = dp->i_mount;
402 struct xfs_bmbt_irec map;
403 xfs_dablk_t lblkno;
404 xfs_fileoff_t lfileoff = 0;
405 __uint8_t *src = args->value;
406 int blkcnt;
407 int valuelen;
408 int nmap;
409 int error;
410 int offset = 0;
411
412 trace_xfs_attr_rmtval_set(args);
413
414 /*
415 * Find a "hole" in the attribute address space large enough for
416 * us to drop the new attribute's value into. Because CRC enable
417 * attributes have headers, we can't just do a straight byte to FSB
418 * conversion and have to take the header space into account.
419 */
420 blkcnt = xfs_attr3_rmt_blocks(mp, args->rmtvaluelen);
421 error = xfs_bmap_first_unused(args->trans, args->dp, blkcnt, &lfileoff,
422 XFS_ATTR_FORK);
423 if (error)
424 return error;
425
426 args->rmtblkno = lblkno = (xfs_dablk_t)lfileoff;
427 args->rmtblkcnt = blkcnt;
428
429 /*
430 * Roll through the "value", allocating blocks on disk as required.
431 */
432 while (blkcnt > 0) {
433 int committed;
434
435 /*
436 * Allocate a single extent, up to the size of the value.
437 */
438 xfs_bmap_init(args->flist, args->firstblock);
439 nmap = 1;
440 error = xfs_bmapi_write(args->trans, dp, (xfs_fileoff_t)lblkno,
441 blkcnt,
442 XFS_BMAPI_ATTRFORK | XFS_BMAPI_METADATA,
443 args->firstblock, args->total, &map, &nmap,
444 args->flist);
445 if (!error) {
446 error = xfs_bmap_finish(&args->trans, args->flist,
447 &committed);
448 }
449 if (error) {
450 ASSERT(committed);
451 args->trans = NULL;
452 xfs_bmap_cancel(args->flist);
453 return error;
454 }
455
456 /*
457 * bmap_finish() may have committed the last trans and started
458 * a new one. We need the inode to be in all transactions.
459 */
460 if (committed)
461 xfs_trans_ijoin(args->trans, dp, 0);
462
463 ASSERT(nmap == 1);
464 ASSERT((map.br_startblock != DELAYSTARTBLOCK) &&
465 (map.br_startblock != HOLESTARTBLOCK));
466 lblkno += map.br_blockcount;
467 blkcnt -= map.br_blockcount;
468
469 /*
470 * Start the next trans in the chain.
471 */
472 error = xfs_trans_roll(&args->trans, dp);
473 if (error)
474 return error;
475 }
476
477 /*
478 * Roll through the "value", copying the attribute value to the
479 * already-allocated blocks. Blocks are written synchronously
480 * so that we can know they are all on disk before we turn off
481 * the INCOMPLETE flag.
482 */
483 lblkno = args->rmtblkno;
484 blkcnt = args->rmtblkcnt;
485 valuelen = args->rmtvaluelen;
486 while (valuelen > 0) {
487 struct xfs_buf *bp;
488 xfs_daddr_t dblkno;
489 int dblkcnt;
490
491 ASSERT(blkcnt > 0);
492
493 xfs_bmap_init(args->flist, args->firstblock);
494 nmap = 1;
495 error = xfs_bmapi_read(dp, (xfs_fileoff_t)lblkno,
496 blkcnt, &map, &nmap,
497 XFS_BMAPI_ATTRFORK);
498 if (error)
499 return error;
500 ASSERT(nmap == 1);
501 ASSERT((map.br_startblock != DELAYSTARTBLOCK) &&
502 (map.br_startblock != HOLESTARTBLOCK));
503
504 dblkno = XFS_FSB_TO_DADDR(mp, map.br_startblock),
505 dblkcnt = XFS_FSB_TO_BB(mp, map.br_blockcount);
506
507 bp = xfs_buf_get(mp->m_ddev_targp, dblkno, dblkcnt, 0);
508 if (!bp)
509 return -ENOMEM;
510 bp->b_ops = &xfs_attr3_rmt_buf_ops;
511
512 xfs_attr_rmtval_copyin(mp, bp, args->dp->i_ino, &offset,
513 &valuelen, &src);
514
515 error = xfs_bwrite(bp); /* GROT: NOTE: synchronous write */
516 xfs_buf_relse(bp);
517 if (error)
518 return error;
519
520
521 /* roll attribute extent map forwards */
522 lblkno += map.br_blockcount;
523 blkcnt -= map.br_blockcount;
524 }
525 ASSERT(valuelen == 0);
526 return 0;
527 }
528
529 /*
530 * Remove the value associated with an attribute by deleting the
531 * out-of-line buffer that it is stored on.
532 */
533 int
534 xfs_attr_rmtval_remove(
535 struct xfs_da_args *args)
536 {
537 struct xfs_mount *mp = args->dp->i_mount;
538 xfs_dablk_t lblkno;
539 int blkcnt;
540 int error;
541 int done;
542
543 trace_xfs_attr_rmtval_remove(args);
544
545 /*
546 * Roll through the "value", invalidating the attribute value's blocks.
547 */
548 lblkno = args->rmtblkno;
549 blkcnt = args->rmtblkcnt;
550 while (blkcnt > 0) {
551 struct xfs_bmbt_irec map;
552 struct xfs_buf *bp;
553 xfs_daddr_t dblkno;
554 int dblkcnt;
555 int nmap;
556
557 /*
558 * Try to remember where we decided to put the value.
559 */
560 nmap = 1;
561 error = xfs_bmapi_read(args->dp, (xfs_fileoff_t)lblkno,
562 blkcnt, &map, &nmap, XFS_BMAPI_ATTRFORK);
563 if (error)
564 return error;
565 ASSERT(nmap == 1);
566 ASSERT((map.br_startblock != DELAYSTARTBLOCK) &&
567 (map.br_startblock != HOLESTARTBLOCK));
568
569 dblkno = XFS_FSB_TO_DADDR(mp, map.br_startblock),
570 dblkcnt = XFS_FSB_TO_BB(mp, map.br_blockcount);
571
572 /*
573 * If the "remote" value is in the cache, remove it.
574 */
575 bp = xfs_incore(mp->m_ddev_targp, dblkno, dblkcnt, XBF_TRYLOCK);
576 if (bp) {
577 xfs_buf_stale(bp);
578 xfs_buf_relse(bp);
579 bp = NULL;
580 }
581
582 lblkno += map.br_blockcount;
583 blkcnt -= map.br_blockcount;
584 }
585
586 /*
587 * Keep de-allocating extents until the remote-value region is gone.
588 */
589 lblkno = args->rmtblkno;
590 blkcnt = args->rmtblkcnt;
591 done = 0;
592 while (!done) {
593 int committed;
594
595 xfs_bmap_init(args->flist, args->firstblock);
596 error = xfs_bunmapi(args->trans, args->dp, lblkno, blkcnt,
597 XFS_BMAPI_ATTRFORK | XFS_BMAPI_METADATA,
598 1, args->firstblock, args->flist,
599 &done);
600 if (!error) {
601 error = xfs_bmap_finish(&args->trans, args->flist,
602 &committed);
603 }
604 if (error) {
605 ASSERT(committed);
606 args->trans = NULL;
607 xfs_bmap_cancel(args->flist);
608 return error;
609 }
610
611 /*
612 * bmap_finish() may have committed the last trans and started
613 * a new one. We need the inode to be in all transactions.
614 */
615 if (committed)
616 xfs_trans_ijoin(args->trans, args->dp, 0);
617
618 /*
619 * Close out trans and start the next one in the chain.
620 */
621 error = xfs_trans_roll(&args->trans, args->dp);
622 if (error)
623 return error;
624 }
625 return 0;
626 }
Linux kernel - Deliverables
This page took 0.058482 seconds and 5 git commands to generate.