2 * This file is part of UBIFS.
4 * Copyright (C) 2006-2008 Nokia Corporation
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published by
8 * the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc., 51
17 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 * Authors: Adrian Hunter
20 * Artem Bityutskiy (Битюцкий Артём)
24 * This file implements functions needed to recover from unclean un-mounts.
25 * When UBIFS is mounted, it checks a flag on the master node to determine if
26 * an un-mount was completed successfully. If not, the process of mounting
27 * incorporates additional checking and fixing of on-flash data structures.
28 * UBIFS always cleans away all remnants of an unclean un-mount, so that
29 * errors do not accumulate. However UBIFS defers recovery if it is mounted
30 * read-only, and the flash is not modified in that case.
33 #include <linux/crc32.h>
34 #include <linux/slab.h>
38 * is_empty - determine whether a buffer is empty (contains all 0xff).
39 * @buf: buffer to clean
40 * @len: length of buffer
42 * This function returns %1 if the buffer is empty (contains all 0xff) otherwise
45 static int is_empty(void *buf, int len)
50 for (i = 0; i < len; i++)
57 * first_non_ff - find offset of the first non-0xff byte.
58 * @buf: buffer to search in
59 * @len: length of buffer
61 * This function returns offset of the first non-0xff byte in @buf or %-1 if
62 * the buffer contains only 0xff bytes.
64 static int first_non_ff(void *buf, int len)
69 for (i = 0; i < len; i++)
76 * get_master_node - get the last valid master node allowing for corruption.
77 * @c: UBIFS file-system description object
79 * @pbuf: buffer containing the LEB read, is returned here
80 * @mst: master node, if found, is returned here
81 * @cor: corruption, if found, is returned here
83 * This function allocates a buffer, reads the LEB into it, and finds and
84 * returns the last valid master node allowing for one area of corruption.
85 * The corrupt area, if there is one, must be consistent with the assumption
86 * that it is the result of an unclean unmount while the master node was being
87 * written. Under those circumstances, it is valid to use the previously written
90 * This function returns %0 on success and a negative error code on failure.
92 static int get_master_node(const struct ubifs_info *c, int lnum, void **pbuf,
93 struct ubifs_mst_node **mst, void **cor)
95 const int sz = c->mst_node_alsz;
99 sbuf = vmalloc(c->leb_size);
103 err = ubi_read(c->ubi, lnum, sbuf, 0, c->leb_size);
104 if (err && err != -EBADMSG)
107 /* Find the first position that is definitely not a node */
111 while (offs + UBIFS_MST_NODE_SZ <= c->leb_size) {
112 struct ubifs_ch *ch = buf;
114 if (le32_to_cpu(ch->magic) != UBIFS_NODE_MAGIC)
120 /* See if there was a valid master node before that */
127 ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1);
128 if (ret != SCANNED_A_NODE && offs) {
129 /* Could have been corruption so check one place back */
133 ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1);
134 if (ret != SCANNED_A_NODE)
136 * We accept only one area of corruption because
137 * we are assuming that it was caused while
138 * trying to write a master node.
142 if (ret == SCANNED_A_NODE) {
143 struct ubifs_ch *ch = buf;
145 if (ch->node_type != UBIFS_MST_NODE)
147 dbg_rcvry("found a master node at %d:%d", lnum, offs);
154 /* Check for corruption */
155 if (offs < c->leb_size) {
156 if (!is_empty(buf, min_t(int, len, sz))) {
158 dbg_rcvry("found corruption at %d:%d", lnum, offs);
164 /* Check remaining empty space */
165 if (offs < c->leb_size)
166 if (!is_empty(buf, len))
181 * write_rcvrd_mst_node - write recovered master node.
182 * @c: UBIFS file-system description object
185 * This function returns %0 on success and a negative error code on failure.
187 static int write_rcvrd_mst_node(struct ubifs_info *c,
188 struct ubifs_mst_node *mst)
190 int err = 0, lnum = UBIFS_MST_LNUM, sz = c->mst_node_alsz;
193 dbg_rcvry("recovery");
195 save_flags = mst->flags;
196 mst->flags |= cpu_to_le32(UBIFS_MST_RCVRY);
198 ubifs_prepare_node(c, mst, UBIFS_MST_NODE_SZ, 1);
199 err = ubi_leb_change(c->ubi, lnum, mst, sz, UBI_SHORTTERM);
202 err = ubi_leb_change(c->ubi, lnum + 1, mst, sz, UBI_SHORTTERM);
206 mst->flags = save_flags;
211 * ubifs_recover_master_node - recover the master node.
212 * @c: UBIFS file-system description object
214 * This function recovers the master node from corruption that may occur due to
215 * an unclean unmount.
217 * This function returns %0 on success and a negative error code on failure.
219 int ubifs_recover_master_node(struct ubifs_info *c)
221 void *buf1 = NULL, *buf2 = NULL, *cor1 = NULL, *cor2 = NULL;
222 struct ubifs_mst_node *mst1 = NULL, *mst2 = NULL, *mst;
223 const int sz = c->mst_node_alsz;
224 int err, offs1, offs2;
226 dbg_rcvry("recovery");
228 err = get_master_node(c, UBIFS_MST_LNUM, &buf1, &mst1, &cor1);
232 err = get_master_node(c, UBIFS_MST_LNUM + 1, &buf2, &mst2, &cor2);
237 offs1 = (void *)mst1 - buf1;
238 if ((le32_to_cpu(mst1->flags) & UBIFS_MST_RCVRY) &&
239 (offs1 == 0 && !cor1)) {
241 * mst1 was written by recovery at offset 0 with no
244 dbg_rcvry("recovery recovery");
247 offs2 = (void *)mst2 - buf2;
248 if (offs1 == offs2) {
249 /* Same offset, so must be the same */
250 if (memcmp((void *)mst1 + UBIFS_CH_SZ,
251 (void *)mst2 + UBIFS_CH_SZ,
252 UBIFS_MST_NODE_SZ - UBIFS_CH_SZ))
255 } else if (offs2 + sz == offs1) {
256 /* 1st LEB was written, 2nd was not */
260 } else if (offs1 == 0 && offs2 + sz >= c->leb_size) {
261 /* 1st LEB was unmapped and written, 2nd not */
269 * 2nd LEB was unmapped and about to be written, so
270 * there must be only one master node in the first LEB
273 if (offs1 != 0 || cor1)
281 * 1st LEB was unmapped and about to be written, so there must
282 * be no room left in 2nd LEB.
284 offs2 = (void *)mst2 - buf2;
285 if (offs2 + sz + sz <= c->leb_size)
290 ubifs_msg("recovered master node from LEB %d",
291 (mst == mst1 ? UBIFS_MST_LNUM : UBIFS_MST_LNUM + 1));
293 memcpy(c->mst_node, mst, UBIFS_MST_NODE_SZ);
296 /* Read-only mode. Keep a copy for switching to rw mode */
297 c->rcvrd_mst_node = kmalloc(sz, GFP_KERNEL);
298 if (!c->rcvrd_mst_node) {
302 memcpy(c->rcvrd_mst_node, c->mst_node, UBIFS_MST_NODE_SZ);
304 /* Write the recovered master node */
305 c->max_sqnum = le64_to_cpu(mst->ch.sqnum) - 1;
306 err = write_rcvrd_mst_node(c, c->mst_node);
319 ubifs_err("failed to recover master node");
321 dbg_err("dumping first master node");
322 dbg_dump_node(c, mst1);
325 dbg_err("dumping second master node");
326 dbg_dump_node(c, mst2);
334 * ubifs_write_rcvrd_mst_node - write the recovered master node.
335 * @c: UBIFS file-system description object
337 * This function writes the master node that was recovered during mounting in
338 * read-only mode and must now be written because we are remounting rw.
340 * This function returns %0 on success and a negative error code on failure.
342 int ubifs_write_rcvrd_mst_node(struct ubifs_info *c)
346 if (!c->rcvrd_mst_node)
348 c->rcvrd_mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
349 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
350 err = write_rcvrd_mst_node(c, c->rcvrd_mst_node);
353 kfree(c->rcvrd_mst_node);
354 c->rcvrd_mst_node = NULL;
359 * is_last_write - determine if an offset was in the last write to a LEB.
360 * @c: UBIFS file-system description object
361 * @buf: buffer to check
362 * @offs: offset to check
364 * This function returns %1 if @offs was in the last write to the LEB whose data
365 * is in @buf, otherwise %0 is returned. The determination is made by checking
366 * for subsequent empty space starting from the next @c->min_io_size boundary.
368 static int is_last_write(const struct ubifs_info *c, void *buf, int offs)
370 int empty_offs, check_len;
374 * Round up to the next @c->min_io_size boundary i.e. @offs is in the
375 * last wbuf written. After that should be empty space.
377 empty_offs = ALIGN(offs + 1, c->min_io_size);
378 check_len = c->leb_size - empty_offs;
379 p = buf + empty_offs - offs;
380 return is_empty(p, check_len);
384 * clean_buf - clean the data from an LEB sitting in a buffer.
385 * @c: UBIFS file-system description object
386 * @buf: buffer to clean
387 * @lnum: LEB number to clean
388 * @offs: offset from which to clean
389 * @len: length of buffer
391 * This function pads up to the next min_io_size boundary (if there is one) and
392 * sets empty space to all 0xff. @buf, @offs and @len are updated to the next
393 * @c->min_io_size boundary.
395 static void clean_buf(const struct ubifs_info *c, void **buf, int lnum,
398 int empty_offs, pad_len;
401 dbg_rcvry("cleaning corruption at %d:%d", lnum, *offs);
403 ubifs_assert(!(*offs & 7));
404 empty_offs = ALIGN(*offs, c->min_io_size);
405 pad_len = empty_offs - *offs;
406 ubifs_pad(c, *buf, pad_len);
410 memset(*buf, 0xff, c->leb_size - empty_offs);
414 * no_more_nodes - determine if there are no more nodes in a buffer.
415 * @c: UBIFS file-system description object
416 * @buf: buffer to check
417 * @len: length of buffer
418 * @lnum: LEB number of the LEB from which @buf was read
419 * @offs: offset from which @buf was read
421 * This function ensures that the corrupted node at @offs is the last thing
422 * written to a LEB. This function returns %1 if more data is not found and
423 * %0 if more data is found.
425 static int no_more_nodes(const struct ubifs_info *c, void *buf, int len,
428 struct ubifs_ch *ch = buf;
429 int skip, dlen = le32_to_cpu(ch->len);
431 /* Check for empty space after the corrupt node's common header */
432 skip = ALIGN(offs + UBIFS_CH_SZ, c->min_io_size) - offs;
433 if (is_empty(buf + skip, len - skip))
436 * The area after the common header size is not empty, so the common
437 * header must be intact. Check it.
439 if (ubifs_check_node(c, buf, lnum, offs, 1, 0) != -EUCLEAN) {
440 dbg_rcvry("unexpected bad common header at %d:%d", lnum, offs);
443 /* Now we know the corrupt node's length we can skip over it */
444 skip = ALIGN(offs + dlen, c->min_io_size) - offs;
445 /* After which there should be empty space */
446 if (is_empty(buf + skip, len - skip))
448 dbg_rcvry("unexpected data at %d:%d", lnum, offs + skip);
453 * fix_unclean_leb - fix an unclean LEB.
454 * @c: UBIFS file-system description object
455 * @sleb: scanned LEB information
456 * @start: offset where scan started
458 static int fix_unclean_leb(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
461 int lnum = sleb->lnum, endpt = start;
463 /* Get the end offset of the last node we are keeping */
464 if (!list_empty(&sleb->nodes)) {
465 struct ubifs_scan_node *snod;
467 snod = list_entry(sleb->nodes.prev,
468 struct ubifs_scan_node, list);
469 endpt = snod->offs + snod->len;
472 if (c->ro_mount && !c->remounting_rw) {
473 /* Add to recovery list */
474 struct ubifs_unclean_leb *ucleb;
476 dbg_rcvry("need to fix LEB %d start %d endpt %d",
477 lnum, start, sleb->endpt);
478 ucleb = kzalloc(sizeof(struct ubifs_unclean_leb), GFP_NOFS);
482 ucleb->endpt = endpt;
483 list_add_tail(&ucleb->list, &c->unclean_leb_list);
485 /* Write the fixed LEB back to flash */
488 dbg_rcvry("fixing LEB %d start %d endpt %d",
489 lnum, start, sleb->endpt);
491 err = ubifs_leb_unmap(c, lnum);
495 int len = ALIGN(endpt, c->min_io_size);
498 err = ubi_read(c->ubi, lnum, sleb->buf, 0,
503 /* Pad to min_io_size */
505 int pad_len = len - ALIGN(endpt, 8);
508 void *buf = sleb->buf + len - pad_len;
510 ubifs_pad(c, buf, pad_len);
513 err = ubi_leb_change(c->ubi, lnum, sleb->buf, len,
523 * drop_incomplete_group - drop nodes from an incomplete group.
524 * @sleb: scanned LEB information
525 * @offs: offset of dropped nodes is returned here
527 * This function returns %1 if nodes are dropped and %0 otherwise.
529 static int drop_incomplete_group(struct ubifs_scan_leb *sleb, int *offs)
533 while (!list_empty(&sleb->nodes)) {
534 struct ubifs_scan_node *snod;
537 snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node,
540 if (ch->group_type != UBIFS_IN_NODE_GROUP)
542 dbg_rcvry("dropping node at %d:%d", sleb->lnum, snod->offs);
544 list_del(&snod->list);
546 sleb->nodes_cnt -= 1;
553 * ubifs_recover_leb - scan and recover a LEB.
554 * @c: UBIFS file-system description object
557 * @sbuf: LEB-sized buffer to use
558 * @grouped: nodes may be grouped for recovery
560 * This function does a scan of a LEB, but caters for errors that might have
561 * been caused by the unclean unmount from which we are attempting to recover.
562 * Returns %0 in case of success, %-EUCLEAN if an unrecoverable corruption is
563 * found, and a negative error code in case of failure.
565 struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum,
566 int offs, void *sbuf, int grouped)
568 int err, len = c->leb_size - offs, need_clean = 0, quiet = 1;
569 int empty_chkd = 0, start = offs;
570 struct ubifs_scan_leb *sleb;
571 void *buf = sbuf + offs;
573 dbg_rcvry("%d:%d", lnum, offs);
575 sleb = ubifs_start_scan(c, lnum, offs, sbuf);
585 dbg_scan("look at LEB %d:%d (%d bytes left)",
591 * Scan quietly until there is an error from which we cannot
594 ret = ubifs_scan_a_node(c, buf, len, lnum, offs, quiet);
596 if (ret == SCANNED_A_NODE) {
597 /* A valid node, and not a padding node */
598 struct ubifs_ch *ch = buf;
601 err = ubifs_add_snod(c, sleb, buf, offs);
604 node_len = ALIGN(le32_to_cpu(ch->len), 8);
612 /* Padding bytes or a valid padding node */
619 if (ret == SCANNED_EMPTY_SPACE) {
620 if (!is_empty(buf, len)) {
621 if (!is_last_write(c, buf, offs))
623 clean_buf(c, &buf, lnum, &offs, &len);
630 if (ret == SCANNED_GARBAGE || ret == SCANNED_A_BAD_PAD_NODE)
631 if (is_last_write(c, buf, offs)) {
632 clean_buf(c, &buf, lnum, &offs, &len);
638 if (ret == SCANNED_A_CORRUPT_NODE)
639 if (no_more_nodes(c, buf, len, lnum, offs)) {
640 clean_buf(c, &buf, lnum, &offs, &len);
647 /* Redo the last scan but noisily */
653 case SCANNED_GARBAGE:
656 case SCANNED_A_CORRUPT_NODE:
657 case SCANNED_A_BAD_PAD_NODE:
667 if (!empty_chkd && !is_empty(buf, len)) {
668 if (is_last_write(c, buf, offs)) {
669 clean_buf(c, &buf, lnum, &offs, &len);
672 int corruption = first_non_ff(buf, len);
674 ubifs_err("corrupt empty space LEB %d:%d, corruption "
675 "starts at %d", lnum, offs, corruption);
676 /* Make sure we dump interesting non-0xFF data */
683 /* Drop nodes from incomplete group */
684 if (grouped && drop_incomplete_group(sleb, &offs)) {
686 len = c->leb_size - offs;
687 clean_buf(c, &buf, lnum, &offs, &len);
691 if (offs % c->min_io_size) {
692 clean_buf(c, &buf, lnum, &offs, &len);
696 ubifs_end_scan(c, sleb, lnum, offs);
699 err = fix_unclean_leb(c, sleb, start);
707 ubifs_scanned_corruption(c, lnum, offs, buf);
710 ubifs_err("LEB %d scanning failed", lnum);
711 ubifs_scan_destroy(sleb);
716 * get_cs_sqnum - get commit start sequence number.
717 * @c: UBIFS file-system description object
718 * @lnum: LEB number of commit start node
719 * @offs: offset of commit start node
720 * @cs_sqnum: commit start sequence number is returned here
722 * This function returns %0 on success and a negative error code on failure.
724 static int get_cs_sqnum(struct ubifs_info *c, int lnum, int offs,
725 unsigned long long *cs_sqnum)
727 struct ubifs_cs_node *cs_node = NULL;
730 dbg_rcvry("at %d:%d", lnum, offs);
731 cs_node = kmalloc(UBIFS_CS_NODE_SZ, GFP_KERNEL);
734 if (c->leb_size - offs < UBIFS_CS_NODE_SZ)
736 err = ubi_read(c->ubi, lnum, (void *)cs_node, offs, UBIFS_CS_NODE_SZ);
737 if (err && err != -EBADMSG)
739 ret = ubifs_scan_a_node(c, cs_node, UBIFS_CS_NODE_SZ, lnum, offs, 0);
740 if (ret != SCANNED_A_NODE) {
741 dbg_err("Not a valid node");
744 if (cs_node->ch.node_type != UBIFS_CS_NODE) {
745 dbg_err("Node a CS node, type is %d", cs_node->ch.node_type);
748 if (le64_to_cpu(cs_node->cmt_no) != c->cmt_no) {
749 dbg_err("CS node cmt_no %llu != current cmt_no %llu",
750 (unsigned long long)le64_to_cpu(cs_node->cmt_no),
754 *cs_sqnum = le64_to_cpu(cs_node->ch.sqnum);
755 dbg_rcvry("commit start sqnum %llu", *cs_sqnum);
762 ubifs_err("failed to get CS sqnum");
768 * ubifs_recover_log_leb - scan and recover a log LEB.
769 * @c: UBIFS file-system description object
772 * @sbuf: LEB-sized buffer to use
774 * This function does a scan of a LEB, but caters for errors that might have
775 * been caused by unclean reboots from which we are attempting to recover
776 * (assume that only the last log LEB can be corrupted by an unclean reboot).
778 * This function returns %0 on success and a negative error code on failure.
780 struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum,
781 int offs, void *sbuf)
783 struct ubifs_scan_leb *sleb;
786 dbg_rcvry("LEB %d", lnum);
787 next_lnum = lnum + 1;
788 if (next_lnum >= UBIFS_LOG_LNUM + c->log_lebs)
789 next_lnum = UBIFS_LOG_LNUM;
790 if (next_lnum != c->ltail_lnum) {
792 * We can only recover at the end of the log, so check that the
793 * next log LEB is empty or out of date.
795 sleb = ubifs_scan(c, next_lnum, 0, sbuf, 0);
798 if (sleb->nodes_cnt) {
799 struct ubifs_scan_node *snod;
800 unsigned long long cs_sqnum = c->cs_sqnum;
802 snod = list_entry(sleb->nodes.next,
803 struct ubifs_scan_node, list);
807 err = get_cs_sqnum(c, lnum, offs, &cs_sqnum);
809 ubifs_scan_destroy(sleb);
813 if (snod->sqnum > cs_sqnum) {
814 ubifs_err("unrecoverable log corruption "
816 ubifs_scan_destroy(sleb);
817 return ERR_PTR(-EUCLEAN);
820 ubifs_scan_destroy(sleb);
822 return ubifs_recover_leb(c, lnum, offs, sbuf, 0);
826 * recover_head - recover a head.
827 * @c: UBIFS file-system description object
828 * @lnum: LEB number of head to recover
829 * @offs: offset of head to recover
830 * @sbuf: LEB-sized buffer to use
832 * This function ensures that there is no data on the flash at a head location.
834 * This function returns %0 on success and a negative error code on failure.
836 static int recover_head(const struct ubifs_info *c, int lnum, int offs,
841 if (c->min_io_size > 1)
842 len = c->min_io_size;
845 if (offs + len > c->leb_size)
846 len = c->leb_size - offs;
851 /* Read at the head location and check it is empty flash */
852 err = ubi_read(c->ubi, lnum, sbuf, offs, len);
853 if (err || !is_empty(sbuf, len)) {
854 dbg_rcvry("cleaning head at %d:%d", lnum, offs);
856 return ubifs_leb_unmap(c, lnum);
857 err = ubi_read(c->ubi, lnum, sbuf, 0, offs);
860 return ubi_leb_change(c->ubi, lnum, sbuf, offs, UBI_UNKNOWN);
867 * ubifs_recover_inl_heads - recover index and LPT heads.
868 * @c: UBIFS file-system description object
869 * @sbuf: LEB-sized buffer to use
871 * This function ensures that there is no data on the flash at the index and
872 * LPT head locations.
874 * This deals with the recovery of a half-completed journal commit. UBIFS is
875 * careful never to overwrite the last version of the index or the LPT. Because
876 * the index and LPT are wandering trees, data from a half-completed commit will
877 * not be referenced anywhere in UBIFS. The data will be either in LEBs that are
878 * assumed to be empty and will be unmapped anyway before use, or in the index
881 * This function returns %0 on success and a negative error code on failure.
883 int ubifs_recover_inl_heads(const struct ubifs_info *c, void *sbuf)
887 ubifs_assert(!c->ro_mount || c->remounting_rw);
889 dbg_rcvry("checking index head at %d:%d", c->ihead_lnum, c->ihead_offs);
890 err = recover_head(c, c->ihead_lnum, c->ihead_offs, sbuf);
894 dbg_rcvry("checking LPT head at %d:%d", c->nhead_lnum, c->nhead_offs);
895 err = recover_head(c, c->nhead_lnum, c->nhead_offs, sbuf);
903 * clean_an_unclean_leb - read and write a LEB to remove corruption.
904 * @c: UBIFS file-system description object
905 * @ucleb: unclean LEB information
906 * @sbuf: LEB-sized buffer to use
908 * This function reads a LEB up to a point pre-determined by the mount recovery,
909 * checks the nodes, and writes the result back to the flash, thereby cleaning
910 * off any following corruption, or non-fatal ECC errors.
912 * This function returns %0 on success and a negative error code on failure.
914 static int clean_an_unclean_leb(const struct ubifs_info *c,
915 struct ubifs_unclean_leb *ucleb, void *sbuf)
917 int err, lnum = ucleb->lnum, offs = 0, len = ucleb->endpt, quiet = 1;
920 dbg_rcvry("LEB %d len %d", lnum, len);
923 /* Nothing to read, just unmap it */
924 err = ubifs_leb_unmap(c, lnum);
930 err = ubi_read(c->ubi, lnum, buf, offs, len);
931 if (err && err != -EBADMSG)
939 /* Scan quietly until there is an error */
940 ret = ubifs_scan_a_node(c, buf, len, lnum, offs, quiet);
942 if (ret == SCANNED_A_NODE) {
943 /* A valid node, and not a padding node */
944 struct ubifs_ch *ch = buf;
947 node_len = ALIGN(le32_to_cpu(ch->len), 8);
955 /* Padding bytes or a valid padding node */
962 if (ret == SCANNED_EMPTY_SPACE) {
963 ubifs_err("unexpected empty space at %d:%d",
969 /* Redo the last scan but noisily */
974 ubifs_scanned_corruption(c, lnum, offs, buf);
978 /* Pad to min_io_size */
979 len = ALIGN(ucleb->endpt, c->min_io_size);
980 if (len > ucleb->endpt) {
981 int pad_len = len - ALIGN(ucleb->endpt, 8);
984 buf = c->sbuf + len - pad_len;
985 ubifs_pad(c, buf, pad_len);
989 /* Write back the LEB atomically */
990 err = ubi_leb_change(c->ubi, lnum, sbuf, len, UBI_UNKNOWN);
994 dbg_rcvry("cleaned LEB %d", lnum);
1000 * ubifs_clean_lebs - clean LEBs recovered during read-only mount.
1001 * @c: UBIFS file-system description object
1002 * @sbuf: LEB-sized buffer to use
1004 * This function cleans a LEB identified during recovery that needs to be
1005 * written but was not because UBIFS was mounted read-only. This happens when
1006 * remounting to read-write mode.
1008 * This function returns %0 on success and a negative error code on failure.
1010 int ubifs_clean_lebs(const struct ubifs_info *c, void *sbuf)
1012 dbg_rcvry("recovery");
1013 while (!list_empty(&c->unclean_leb_list)) {
1014 struct ubifs_unclean_leb *ucleb;
1017 ucleb = list_entry(c->unclean_leb_list.next,
1018 struct ubifs_unclean_leb, list);
1019 err = clean_an_unclean_leb(c, ucleb, sbuf);
1022 list_del(&ucleb->list);
1029 * ubifs_rcvry_gc_commit - recover the GC LEB number and run the commit.
1030 * @c: UBIFS file-system description object
1032 * Out-of-place garbage collection requires always one empty LEB with which to
1033 * start garbage collection. The LEB number is recorded in c->gc_lnum and is
1034 * written to the master node on unmounting. In the case of an unclean unmount
1035 * the value of gc_lnum recorded in the master node is out of date and cannot
1036 * be used. Instead, recovery must allocate an empty LEB for this purpose.
1037 * However, there may not be enough empty space, in which case it must be
1038 * possible to GC the dirtiest LEB into the GC head LEB.
1040 * This function also runs the commit which causes the TNC updates from
1041 * size-recovery and orphans to be written to the flash. That is important to
1042 * ensure correct replay order for subsequent mounts.
1044 * This function returns %0 on success and a negative error code on failure.
1046 int ubifs_rcvry_gc_commit(struct ubifs_info *c)
1048 struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
1049 struct ubifs_lprops lp;
1053 if (wbuf->lnum == -1) {
1054 dbg_rcvry("no GC head LEB");
1058 * See whether the used space in the dirtiest LEB fits in the GC head
1061 if (wbuf->offs == c->leb_size) {
1062 dbg_rcvry("no room in GC head LEB");
1065 err = ubifs_find_dirty_leb(c, &lp, wbuf->offs, 2);
1068 * There are no dirty or empty LEBs subject to here being
1069 * enough for the index. Try to use
1070 * 'ubifs_find_free_leb_for_idx()', which will return any empty
1071 * LEBs (ignoring index requirements). If the index then
1072 * doesn't have enough LEBs the recovery commit will fail -
1073 * which is the same result anyway i.e. recovery fails. So
1074 * there is no problem ignoring index requirements and just
1075 * grabbing a free LEB since we have already established there
1076 * is not a dirty LEB we could have used instead.
1078 if (err == -ENOSPC) {
1079 dbg_rcvry("could not find a dirty LEB");
1084 ubifs_assert(!(lp.flags & LPROPS_INDEX));
1086 if (lp.free + lp.dirty == c->leb_size) {
1087 /* An empty LEB was returned */
1088 if (lp.free != c->leb_size) {
1089 err = ubifs_change_one_lp(c, lnum, c->leb_size,
1094 err = ubifs_leb_unmap(c, lnum);
1098 dbg_rcvry("allocated LEB %d for GC", lnum);
1099 /* Run the commit */
1100 dbg_rcvry("committing");
1101 return ubifs_run_commit(c);
1104 * There was no empty LEB so the used space in the dirtiest LEB must fit
1105 * in the GC head LEB.
1107 if (lp.free + lp.dirty < wbuf->offs) {
1108 dbg_rcvry("LEB %d doesn't fit in GC head LEB %d:%d",
1109 lnum, wbuf->lnum, wbuf->offs);
1110 err = ubifs_return_leb(c, lnum);
1116 * We run the commit before garbage collection otherwise subsequent
1117 * mounts will see the GC and orphan deletion in a different order.
1119 dbg_rcvry("committing");
1120 err = ubifs_run_commit(c);
1124 * The data in the dirtiest LEB fits in the GC head LEB, so do the GC
1125 * - use locking to keep 'ubifs_assert()' happy.
1127 dbg_rcvry("GC'ing LEB %d", lnum);
1128 mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
1129 err = ubifs_garbage_collect_leb(c, &lp);
1131 int err2 = ubifs_wbuf_sync_nolock(wbuf);
1136 mutex_unlock(&wbuf->io_mutex);
1138 dbg_err("GC failed, error %d", err);
1143 if (err != LEB_RETAINED) {
1144 dbg_err("GC returned %d", err);
1147 err = ubifs_leb_unmap(c, c->gc_lnum);
1150 dbg_rcvry("allocated LEB %d for GC", lnum);
1155 * There is no GC head LEB or the free space in the GC head LEB is too
1156 * small, or there are not dirty LEBs. Allocate gc_lnum by calling
1157 * 'ubifs_find_free_leb_for_idx()' so GC is not run.
1159 lnum = ubifs_find_free_leb_for_idx(c);
1161 dbg_err("could not find an empty LEB");
1164 /* And reset the index flag */
1165 err = ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0,
1170 dbg_rcvry("allocated LEB %d for GC", lnum);
1171 /* Run the commit */
1172 dbg_rcvry("committing");
1173 return ubifs_run_commit(c);
1177 * struct size_entry - inode size information for recovery.
1178 * @rb: link in the RB-tree of sizes
1179 * @inum: inode number
1180 * @i_size: size on inode
1181 * @d_size: maximum size based on data nodes
1182 * @exists: indicates whether the inode exists
1183 * @inode: inode if pinned in memory awaiting rw mode to fix it
1191 struct inode *inode;
1195 * add_ino - add an entry to the size tree.
1196 * @c: UBIFS file-system description object
1197 * @inum: inode number
1198 * @i_size: size on inode
1199 * @d_size: maximum size based on data nodes
1200 * @exists: indicates whether the inode exists
1202 static int add_ino(struct ubifs_info *c, ino_t inum, loff_t i_size,
1203 loff_t d_size, int exists)
1205 struct rb_node **p = &c->size_tree.rb_node, *parent = NULL;
1206 struct size_entry *e;
1210 e = rb_entry(parent, struct size_entry, rb);
1214 p = &(*p)->rb_right;
1217 e = kzalloc(sizeof(struct size_entry), GFP_KERNEL);
1226 rb_link_node(&e->rb, parent, p);
1227 rb_insert_color(&e->rb, &c->size_tree);
1233 * find_ino - find an entry on the size tree.
1234 * @c: UBIFS file-system description object
1235 * @inum: inode number
1237 static struct size_entry *find_ino(struct ubifs_info *c, ino_t inum)
1239 struct rb_node *p = c->size_tree.rb_node;
1240 struct size_entry *e;
1243 e = rb_entry(p, struct size_entry, rb);
1246 else if (inum > e->inum)
1255 * remove_ino - remove an entry from the size tree.
1256 * @c: UBIFS file-system description object
1257 * @inum: inode number
1259 static void remove_ino(struct ubifs_info *c, ino_t inum)
1261 struct size_entry *e = find_ino(c, inum);
1265 rb_erase(&e->rb, &c->size_tree);
1270 * ubifs_destroy_size_tree - free resources related to the size tree.
1271 * @c: UBIFS file-system description object
1273 void ubifs_destroy_size_tree(struct ubifs_info *c)
1275 struct rb_node *this = c->size_tree.rb_node;
1276 struct size_entry *e;
1279 if (this->rb_left) {
1280 this = this->rb_left;
1282 } else if (this->rb_right) {
1283 this = this->rb_right;
1286 e = rb_entry(this, struct size_entry, rb);
1289 this = rb_parent(this);
1291 if (this->rb_left == &e->rb)
1292 this->rb_left = NULL;
1294 this->rb_right = NULL;
1298 c->size_tree = RB_ROOT;
1302 * ubifs_recover_size_accum - accumulate inode sizes for recovery.
1303 * @c: UBIFS file-system description object
1305 * @deletion: node is for a deletion
1306 * @new_size: inode size
1308 * This function has two purposes:
1309 * 1) to ensure there are no data nodes that fall outside the inode size
1310 * 2) to ensure there are no data nodes for inodes that do not exist
1311 * To accomplish those purposes, a rb-tree is constructed containing an entry
1312 * for each inode number in the journal that has not been deleted, and recording
1313 * the size from the inode node, the maximum size of any data node (also altered
1314 * by truncations) and a flag indicating a inode number for which no inode node
1315 * was present in the journal.
1317 * Note that there is still the possibility that there are data nodes that have
1318 * been committed that are beyond the inode size, however the only way to find
1319 * them would be to scan the entire index. Alternatively, some provision could
1320 * be made to record the size of inodes at the start of commit, which would seem
1321 * very cumbersome for a scenario that is quite unlikely and the only negative
1322 * consequence of which is wasted space.
1324 * This functions returns %0 on success and a negative error code on failure.
1326 int ubifs_recover_size_accum(struct ubifs_info *c, union ubifs_key *key,
1327 int deletion, loff_t new_size)
1329 ino_t inum = key_inum(c, key);
1330 struct size_entry *e;
1333 switch (key_type(c, key)) {
1336 remove_ino(c, inum);
1338 e = find_ino(c, inum);
1340 e->i_size = new_size;
1343 err = add_ino(c, inum, new_size, 0, 1);
1349 case UBIFS_DATA_KEY:
1350 e = find_ino(c, inum);
1352 if (new_size > e->d_size)
1353 e->d_size = new_size;
1355 err = add_ino(c, inum, 0, new_size, 0);
1360 case UBIFS_TRUN_KEY:
1361 e = find_ino(c, inum);
1363 e->d_size = new_size;
1370 * fix_size_in_place - fix inode size in place on flash.
1371 * @c: UBIFS file-system description object
1372 * @e: inode size information for recovery
1374 static int fix_size_in_place(struct ubifs_info *c, struct size_entry *e)
1376 struct ubifs_ino_node *ino = c->sbuf;
1378 union ubifs_key key;
1379 int err, lnum, offs, len;
1383 /* Locate the inode node LEB number and offset */
1384 ino_key_init(c, &key, e->inum);
1385 err = ubifs_tnc_locate(c, &key, ino, &lnum, &offs);
1389 * If the size recorded on the inode node is greater than the size that
1390 * was calculated from nodes in the journal then don't change the inode.
1392 i_size = le64_to_cpu(ino->size);
1393 if (i_size >= e->d_size)
1396 err = ubi_read(c->ubi, lnum, c->sbuf, 0, c->leb_size);
1399 /* Change the size field and recalculate the CRC */
1400 ino = c->sbuf + offs;
1401 ino->size = cpu_to_le64(e->d_size);
1402 len = le32_to_cpu(ino->ch.len);
1403 crc = crc32(UBIFS_CRC32_INIT, (void *)ino + 8, len - 8);
1404 ino->ch.crc = cpu_to_le32(crc);
1405 /* Work out where data in the LEB ends and free space begins */
1407 len = c->leb_size - 1;
1408 while (p[len] == 0xff)
1410 len = ALIGN(len + 1, c->min_io_size);
1411 /* Atomically write the fixed LEB back again */
1412 err = ubi_leb_change(c->ubi, lnum, c->sbuf, len, UBI_UNKNOWN);
1415 dbg_rcvry("inode %lu at %d:%d size %lld -> %lld ",
1416 (unsigned long)e->inum, lnum, offs, i_size, e->d_size);
1420 ubifs_warn("inode %lu failed to fix size %lld -> %lld error %d",
1421 (unsigned long)e->inum, e->i_size, e->d_size, err);
1426 * ubifs_recover_size - recover inode size.
1427 * @c: UBIFS file-system description object
1429 * This function attempts to fix inode size discrepancies identified by the
1430 * 'ubifs_recover_size_accum()' function.
1432 * This functions returns %0 on success and a negative error code on failure.
1434 int ubifs_recover_size(struct ubifs_info *c)
1436 struct rb_node *this = rb_first(&c->size_tree);
1439 struct size_entry *e;
1442 e = rb_entry(this, struct size_entry, rb);
1444 union ubifs_key key;
1446 ino_key_init(c, &key, e->inum);
1447 err = ubifs_tnc_lookup(c, &key, c->sbuf);
1448 if (err && err != -ENOENT)
1450 if (err == -ENOENT) {
1451 /* Remove data nodes that have no inode */
1452 dbg_rcvry("removing ino %lu",
1453 (unsigned long)e->inum);
1454 err = ubifs_tnc_remove_ino(c, e->inum);
1458 struct ubifs_ino_node *ino = c->sbuf;
1461 e->i_size = le64_to_cpu(ino->size);
1464 if (e->exists && e->i_size < e->d_size) {
1465 if (!e->inode && c->ro_mount) {
1466 /* Fix the inode size and pin it in memory */
1467 struct inode *inode;
1469 inode = ubifs_iget(c->vfs_sb, e->inum);
1471 return PTR_ERR(inode);
1472 if (inode->i_size < e->d_size) {
1473 dbg_rcvry("ino %lu size %lld -> %lld",
1474 (unsigned long)e->inum,
1475 e->d_size, inode->i_size);
1476 inode->i_size = e->d_size;
1477 ubifs_inode(inode)->ui_size = e->d_size;
1479 this = rb_next(this);
1484 /* Fix the size in place */
1485 err = fix_size_in_place(c, e);
1492 this = rb_next(this);
1493 rb_erase(&e->rb, &c->size_tree);