2 * Copyright (c) International Business Machines Corp., 2006
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
12 * the GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 * Author: Artem Bityutskiy (Битюцкий Артём)
22 * UBI scanning sub-system.
24 * This sub-system is responsible for scanning the flash media, checking UBI
25 * headers and providing complete information about the UBI flash image.
27 * The scanning information is represented by a &struct ubi_scan_info' object.
28 * Information about found volumes is represented by &struct ubi_scan_volume
29 * objects which are kept in volume RB-tree with root at the @volumes field.
30 * The RB-tree is indexed by the volume ID.
32 * Found logical eraseblocks are represented by &struct ubi_scan_leb objects.
33 * These objects are kept in per-volume RB-trees with the root at the
34 * corresponding &struct ubi_scan_volume object. To put it differently, we keep
35 * an RB-tree of per-volume objects and each of these objects is the root of
36 * RB-tree of per-eraseblock objects.
38 * Corrupted physical eraseblocks are put to the @corr list, free physical
39 * eraseblocks are put to the @free list and the physical eraseblock to be
40 * erased are put to the @erase list.
43 #include <linux/err.h>
44 #include <linux/crc32.h>
45 #include <linux/math64.h>
48 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
49 static int paranoid_check_si(struct ubi_device *ubi, struct ubi_scan_info *si);
51 #define paranoid_check_si(ubi, si) 0
54 /* Temporary variables used during scanning */
55 static struct ubi_ec_hdr *ech;
56 static struct ubi_vid_hdr *vidh;
59 * add_to_list - add physical eraseblock to a list.
60 * @si: scanning information
61 * @pnum: physical eraseblock number to add
62 * @ec: erase counter of the physical eraseblock
63 * @list: the list to add to
65 * This function adds physical eraseblock @pnum to free, erase, corrupted or
66 * alien lists. Returns zero in case of success and a negative error code in
69 static int add_to_list(struct ubi_scan_info *si, int pnum, int ec,
70 struct list_head *list)
72 struct ubi_scan_leb *seb;
74 if (list == &si->free)
75 dbg_bld("add to free: PEB %d, EC %d", pnum, ec);
76 else if (list == &si->erase)
77 dbg_bld("add to erase: PEB %d, EC %d", pnum, ec);
78 else if (list == &si->corr)
79 dbg_bld("add to corrupted: PEB %d, EC %d", pnum, ec);
80 else if (list == &si->alien)
81 dbg_bld("add to alien: PEB %d, EC %d", pnum, ec);
85 seb = kmalloc(sizeof(struct ubi_scan_leb), GFP_KERNEL);
91 list_add_tail(&seb->u.list, list);
96 * validate_vid_hdr - check volume identifier header.
97 * @vid_hdr: the volume identifier header to check
98 * @sv: information about the volume this logical eraseblock belongs to
99 * @pnum: physical eraseblock number the VID header came from
101 * This function checks that data stored in @vid_hdr is consistent. Returns
102 * non-zero if an inconsistency was found and zero if not.
104 * Note, UBI does sanity check of everything it reads from the flash media.
105 * Most of the checks are done in the I/O sub-system. Here we check that the
106 * information in the VID header is consistent to the information in other VID
107 * headers of the same volume.
109 static int validate_vid_hdr(const struct ubi_vid_hdr *vid_hdr,
110 const struct ubi_scan_volume *sv, int pnum)
112 int vol_type = vid_hdr->vol_type;
113 int vol_id = be32_to_cpu(vid_hdr->vol_id);
114 int used_ebs = be32_to_cpu(vid_hdr->used_ebs);
115 int data_pad = be32_to_cpu(vid_hdr->data_pad);
117 if (sv->leb_count != 0) {
121 * This is not the first logical eraseblock belonging to this
122 * volume. Ensure that the data in its VID header is consistent
123 * to the data in previous logical eraseblock headers.
126 if (vol_id != sv->vol_id) {
127 dbg_err("inconsistent vol_id");
131 if (sv->vol_type == UBI_STATIC_VOLUME)
132 sv_vol_type = UBI_VID_STATIC;
134 sv_vol_type = UBI_VID_DYNAMIC;
136 if (vol_type != sv_vol_type) {
137 dbg_err("inconsistent vol_type");
141 if (used_ebs != sv->used_ebs) {
142 dbg_err("inconsistent used_ebs");
146 if (data_pad != sv->data_pad) {
147 dbg_err("inconsistent data_pad");
155 ubi_err("inconsistent VID header at PEB %d", pnum);
156 ubi_dbg_dump_vid_hdr(vid_hdr);
162 * add_volume - add volume to the scanning information.
163 * @si: scanning information
164 * @vol_id: ID of the volume to add
165 * @pnum: physical eraseblock number
166 * @vid_hdr: volume identifier header
168 * If the volume corresponding to the @vid_hdr logical eraseblock is already
169 * present in the scanning information, this function does nothing. Otherwise
170 * it adds corresponding volume to the scanning information. Returns a pointer
171 * to the scanning volume object in case of success and a negative error code
172 * in case of failure.
174 static struct ubi_scan_volume *add_volume(struct ubi_scan_info *si, int vol_id,
176 const struct ubi_vid_hdr *vid_hdr)
178 struct ubi_scan_volume *sv;
179 struct rb_node **p = &si->volumes.rb_node, *parent = NULL;
181 ubi_assert(vol_id == be32_to_cpu(vid_hdr->vol_id));
183 /* Walk the volume RB-tree to look if this volume is already present */
186 sv = rb_entry(parent, struct ubi_scan_volume, rb);
188 if (vol_id == sv->vol_id)
191 if (vol_id > sv->vol_id)
197 /* The volume is absent - add it */
198 sv = kmalloc(sizeof(struct ubi_scan_volume), GFP_KERNEL);
200 return ERR_PTR(-ENOMEM);
202 sv->highest_lnum = sv->leb_count = 0;
205 sv->used_ebs = be32_to_cpu(vid_hdr->used_ebs);
206 sv->data_pad = be32_to_cpu(vid_hdr->data_pad);
207 sv->compat = vid_hdr->compat;
208 sv->vol_type = vid_hdr->vol_type == UBI_VID_DYNAMIC ? UBI_DYNAMIC_VOLUME
210 if (vol_id > si->highest_vol_id)
211 si->highest_vol_id = vol_id;
213 rb_link_node(&sv->rb, parent, p);
214 rb_insert_color(&sv->rb, &si->volumes);
216 dbg_bld("added volume %d", vol_id);
221 * compare_lebs - find out which logical eraseblock is newer.
222 * @ubi: UBI device description object
223 * @seb: first logical eraseblock to compare
224 * @pnum: physical eraseblock number of the second logical eraseblock to
226 * @vid_hdr: volume identifier header of the second logical eraseblock
228 * This function compares 2 copies of a LEB and informs which one is newer. In
229 * case of success this function returns a positive value, in case of failure, a
230 * negative error code is returned. The success return codes use the following
232 * o bit 0 is cleared: the first PEB (described by @seb) is newer then the
233 * second PEB (described by @pnum and @vid_hdr);
234 * o bit 0 is set: the second PEB is newer;
235 * o bit 1 is cleared: no bit-flips were detected in the newer LEB;
236 * o bit 1 is set: bit-flips were detected in the newer LEB;
237 * o bit 2 is cleared: the older LEB is not corrupted;
238 * o bit 2 is set: the older LEB is corrupted.
240 static int compare_lebs(struct ubi_device *ubi, const struct ubi_scan_leb *seb,
241 int pnum, const struct ubi_vid_hdr *vid_hdr)
244 int len, err, second_is_newer, bitflips = 0, corrupted = 0;
245 uint32_t data_crc, crc;
246 struct ubi_vid_hdr *vh = NULL;
247 unsigned long long sqnum2 = be64_to_cpu(vid_hdr->sqnum);
249 if (sqnum2 == seb->sqnum) {
251 * This must be a really ancient UBI image which has been
252 * created before sequence numbers support has been added. At
253 * that times we used 32-bit LEB versions stored in logical
254 * eraseblocks. That was before UBI got into mainline. We do not
255 * support these images anymore. Well, those images will work
256 * still work, but only if no unclean reboots happened.
258 ubi_err("unsupported on-flash UBI format\n");
262 /* Obviously the LEB with lower sequence counter is older */
263 second_is_newer = !!(sqnum2 > seb->sqnum);
266 * Now we know which copy is newer. If the copy flag of the PEB with
267 * newer version is not set, then we just return, otherwise we have to
268 * check data CRC. For the second PEB we already have the VID header,
269 * for the first one - we'll need to re-read it from flash.
271 * Note: this may be optimized so that we wouldn't read twice.
274 if (second_is_newer) {
275 if (!vid_hdr->copy_flag) {
276 /* It is not a copy, so it is newer */
277 dbg_bld("second PEB %d is newer, copy_flag is unset",
284 vh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
288 err = ubi_io_read_vid_hdr(ubi, pnum, vh, 0);
290 if (err == UBI_IO_BITFLIPS)
293 dbg_err("VID of PEB %d header is bad, but it "
294 "was OK earlier", pnum);
302 if (!vh->copy_flag) {
303 /* It is not a copy, so it is newer */
304 dbg_bld("first PEB %d is newer, copy_flag is unset",
313 /* Read the data of the copy and check the CRC */
315 len = be32_to_cpu(vid_hdr->data_size);
322 err = ubi_io_read_data(ubi, buf, pnum, 0, len);
323 if (err && err != UBI_IO_BITFLIPS && err != -EBADMSG)
326 data_crc = be32_to_cpu(vid_hdr->data_crc);
327 crc = crc32(UBI_CRC32_INIT, buf, len);
328 if (crc != data_crc) {
329 dbg_bld("PEB %d CRC error: calculated %#08x, must be %#08x",
330 pnum, crc, data_crc);
333 second_is_newer = !second_is_newer;
335 dbg_bld("PEB %d CRC is OK", pnum);
340 ubi_free_vid_hdr(ubi, vh);
343 dbg_bld("second PEB %d is newer, copy_flag is set", pnum);
345 dbg_bld("first PEB %d is newer, copy_flag is set", pnum);
347 return second_is_newer | (bitflips << 1) | (corrupted << 2);
352 ubi_free_vid_hdr(ubi, vh);
357 * ubi_scan_add_used - add physical eraseblock to the scanning information.
358 * @ubi: UBI device description object
359 * @si: scanning information
360 * @pnum: the physical eraseblock number
362 * @vid_hdr: the volume identifier header
363 * @bitflips: if bit-flips were detected when this physical eraseblock was read
365 * This function adds information about a used physical eraseblock to the
366 * 'used' tree of the corresponding volume. The function is rather complex
367 * because it has to handle cases when this is not the first physical
368 * eraseblock belonging to the same logical eraseblock, and the newer one has
369 * to be picked, while the older one has to be dropped. This function returns
370 * zero in case of success and a negative error code in case of failure.
372 int ubi_scan_add_used(struct ubi_device *ubi, struct ubi_scan_info *si,
373 int pnum, int ec, const struct ubi_vid_hdr *vid_hdr,
376 int err, vol_id, lnum;
377 unsigned long long sqnum;
378 struct ubi_scan_volume *sv;
379 struct ubi_scan_leb *seb;
380 struct rb_node **p, *parent = NULL;
382 vol_id = be32_to_cpu(vid_hdr->vol_id);
383 lnum = be32_to_cpu(vid_hdr->lnum);
384 sqnum = be64_to_cpu(vid_hdr->sqnum);
386 dbg_bld("PEB %d, LEB %d:%d, EC %d, sqnum %llu, bitflips %d",
387 pnum, vol_id, lnum, ec, sqnum, bitflips);
389 sv = add_volume(si, vol_id, pnum, vid_hdr);
393 if (si->max_sqnum < sqnum)
394 si->max_sqnum = sqnum;
397 * Walk the RB-tree of logical eraseblocks of volume @vol_id to look
398 * if this is the first instance of this logical eraseblock or not.
400 p = &sv->root.rb_node;
405 seb = rb_entry(parent, struct ubi_scan_leb, u.rb);
406 if (lnum != seb->lnum) {
407 if (lnum < seb->lnum)
415 * There is already a physical eraseblock describing the same
416 * logical eraseblock present.
419 dbg_bld("this LEB already exists: PEB %d, sqnum %llu, "
420 "EC %d", seb->pnum, seb->sqnum, seb->ec);
423 * Make sure that the logical eraseblocks have different
424 * sequence numbers. Otherwise the image is bad.
426 * However, if the sequence number is zero, we assume it must
427 * be an ancient UBI image from the era when UBI did not have
428 * sequence numbers. We still can attach these images, unless
429 * there is a need to distinguish between old and new
430 * eraseblocks, in which case we'll refuse the image in
431 * 'compare_lebs()'. In other words, we attach old clean
432 * images, but refuse attaching old images with duplicated
433 * logical eraseblocks because there was an unclean reboot.
435 if (seb->sqnum == sqnum && sqnum != 0) {
436 ubi_err("two LEBs with same sequence number %llu",
438 ubi_dbg_dump_seb(seb, 0);
439 ubi_dbg_dump_vid_hdr(vid_hdr);
444 * Now we have to drop the older one and preserve the newer
447 cmp_res = compare_lebs(ubi, seb, pnum, vid_hdr);
453 * This logical eraseblock is newer then the one
456 err = validate_vid_hdr(vid_hdr, sv, pnum);
461 err = add_to_list(si, seb->pnum, seb->ec,
464 err = add_to_list(si, seb->pnum, seb->ec,
471 seb->scrub = ((cmp_res & 2) || bitflips);
474 if (sv->highest_lnum == lnum)
476 be32_to_cpu(vid_hdr->data_size);
481 * This logical eraseblock is older than the one found
485 return add_to_list(si, pnum, ec, &si->corr);
487 return add_to_list(si, pnum, ec, &si->erase);
492 * We've met this logical eraseblock for the first time, add it to the
493 * scanning information.
496 err = validate_vid_hdr(vid_hdr, sv, pnum);
500 seb = kmalloc(sizeof(struct ubi_scan_leb), GFP_KERNEL);
508 seb->scrub = bitflips;
510 if (sv->highest_lnum <= lnum) {
511 sv->highest_lnum = lnum;
512 sv->last_data_size = be32_to_cpu(vid_hdr->data_size);
516 rb_link_node(&seb->u.rb, parent, p);
517 rb_insert_color(&seb->u.rb, &sv->root);
522 * ubi_scan_find_sv - find volume in the scanning information.
523 * @si: scanning information
524 * @vol_id: the requested volume ID
526 * This function returns a pointer to the volume description or %NULL if there
527 * are no data about this volume in the scanning information.
529 struct ubi_scan_volume *ubi_scan_find_sv(const struct ubi_scan_info *si,
532 struct ubi_scan_volume *sv;
533 struct rb_node *p = si->volumes.rb_node;
536 sv = rb_entry(p, struct ubi_scan_volume, rb);
538 if (vol_id == sv->vol_id)
541 if (vol_id > sv->vol_id)
551 * ubi_scan_find_seb - find LEB in the volume scanning information.
552 * @sv: a pointer to the volume scanning information
553 * @lnum: the requested logical eraseblock
555 * This function returns a pointer to the scanning logical eraseblock or %NULL
556 * if there are no data about it in the scanning volume information.
558 struct ubi_scan_leb *ubi_scan_find_seb(const struct ubi_scan_volume *sv,
561 struct ubi_scan_leb *seb;
562 struct rb_node *p = sv->root.rb_node;
565 seb = rb_entry(p, struct ubi_scan_leb, u.rb);
567 if (lnum == seb->lnum)
570 if (lnum > seb->lnum)
580 * ubi_scan_rm_volume - delete scanning information about a volume.
581 * @si: scanning information
582 * @sv: the volume scanning information to delete
584 void ubi_scan_rm_volume(struct ubi_scan_info *si, struct ubi_scan_volume *sv)
587 struct ubi_scan_leb *seb;
589 dbg_bld("remove scanning information about volume %d", sv->vol_id);
591 while ((rb = rb_first(&sv->root))) {
592 seb = rb_entry(rb, struct ubi_scan_leb, u.rb);
593 rb_erase(&seb->u.rb, &sv->root);
594 list_add_tail(&seb->u.list, &si->erase);
597 rb_erase(&sv->rb, &si->volumes);
603 * ubi_scan_erase_peb - erase a physical eraseblock.
604 * @ubi: UBI device description object
605 * @si: scanning information
606 * @pnum: physical eraseblock number to erase;
607 * @ec: erase counter value to write (%UBI_SCAN_UNKNOWN_EC if it is unknown)
609 * This function erases physical eraseblock 'pnum', and writes the erase
610 * counter header to it. This function should only be used on UBI device
611 * initialization stages, when the EBA sub-system had not been yet initialized.
612 * This function returns zero in case of success and a negative error code in
615 int ubi_scan_erase_peb(struct ubi_device *ubi, const struct ubi_scan_info *si,
619 struct ubi_ec_hdr *ec_hdr;
621 if ((long long)ec >= UBI_MAX_ERASECOUNTER) {
623 * Erase counter overflow. Upgrade UBI and use 64-bit
624 * erase counters internally.
626 ubi_err("erase counter overflow at PEB %d, EC %d", pnum, ec);
630 ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
634 ec_hdr->ec = cpu_to_be64(ec);
636 err = ubi_io_sync_erase(ubi, pnum, 0);
640 err = ubi_io_write_ec_hdr(ubi, pnum, ec_hdr);
648 * ubi_scan_get_free_peb - get a free physical eraseblock.
649 * @ubi: UBI device description object
650 * @si: scanning information
652 * This function returns a free physical eraseblock. It is supposed to be
653 * called on the UBI initialization stages when the wear-leveling sub-system is
654 * not initialized yet. This function picks a physical eraseblocks from one of
655 * the lists, writes the EC header if it is needed, and removes it from the
658 * This function returns scanning physical eraseblock information in case of
659 * success and an error code in case of failure.
661 struct ubi_scan_leb *ubi_scan_get_free_peb(struct ubi_device *ubi,
662 struct ubi_scan_info *si)
665 struct ubi_scan_leb *seb;
667 if (!list_empty(&si->free)) {
668 seb = list_entry(si->free.next, struct ubi_scan_leb, u.list);
669 list_del(&seb->u.list);
670 dbg_bld("return free PEB %d, EC %d", seb->pnum, seb->ec);
674 for (i = 0; i < 2; i++) {
675 struct list_head *head;
676 struct ubi_scan_leb *tmp_seb;
684 * We try to erase the first physical eraseblock from the @head
685 * list and pick it if we succeed, or try to erase the
686 * next one if not. And so forth. We don't want to take care
687 * about bad eraseblocks here - they'll be handled later.
689 list_for_each_entry_safe(seb, tmp_seb, head, u.list) {
690 if (seb->ec == UBI_SCAN_UNKNOWN_EC)
691 seb->ec = si->mean_ec;
693 err = ubi_scan_erase_peb(ubi, si, seb->pnum, seb->ec+1);
698 list_del(&seb->u.list);
699 dbg_bld("return PEB %d, EC %d", seb->pnum, seb->ec);
704 ubi_err("no eraseblocks found");
705 return ERR_PTR(-ENOSPC);
709 * process_eb - read, check UBI headers, and add them to scanning information.
710 * @ubi: UBI device description object
711 * @si: scanning information
712 * @pnum: the physical eraseblock number
714 * This function returns a zero if the physical eraseblock was successfully
715 * handled and a negative error code in case of failure.
717 static int process_eb(struct ubi_device *ubi, struct ubi_scan_info *si,
720 long long uninitialized_var(ec);
721 int err, bitflips = 0, vol_id, ec_corr = 0;
723 dbg_bld("scan PEB %d", pnum);
725 /* Skip bad physical eraseblocks */
726 err = ubi_io_is_bad(ubi, pnum);
731 * FIXME: this is actually duty of the I/O sub-system to
732 * initialize this, but MTD does not provide enough
735 si->bad_peb_count += 1;
739 err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
742 else if (err == UBI_IO_BITFLIPS)
744 else if (err == UBI_IO_PEB_EMPTY)
745 return add_to_list(si, pnum, UBI_SCAN_UNKNOWN_EC, &si->erase);
746 else if (err == UBI_IO_BAD_EC_HDR) {
748 * We have to also look at the VID header, possibly it is not
749 * corrupted. Set %bitflips flag in order to make this PEB be
750 * moved and EC be re-created.
753 ec = UBI_SCAN_UNKNOWN_EC;
762 /* Make sure UBI version is OK */
763 if (ech->version != UBI_VERSION) {
764 ubi_err("this UBI version is %d, image version is %d",
765 UBI_VERSION, (int)ech->version);
769 ec = be64_to_cpu(ech->ec);
770 if (ec > UBI_MAX_ERASECOUNTER) {
772 * Erase counter overflow. The EC headers have 64 bits
773 * reserved, but we anyway make use of only 31 bit
774 * values, as this seems to be enough for any existing
775 * flash. Upgrade UBI and use 64-bit erase counters
778 ubi_err("erase counter overflow, max is %d",
779 UBI_MAX_ERASECOUNTER);
780 ubi_dbg_dump_ec_hdr(ech);
785 * Make sure that all PEBs have the same image sequence number.
786 * This allows us to detect situations when users flash UBI
787 * images incorrectly, so that the flash has the new UBI image
788 * and leftovers from the old one. This feature was added
789 * relatively recently, and the sequence number was always
790 * zero, because old UBI implementations always set it to zero.
791 * For this reasons, we do not panic if some PEBs have zero
792 * sequence number, while other PEBs have non-zero sequence
795 image_seq = be32_to_cpu(ech->image_seq);
796 if (!si->image_seq_set) {
797 ubi->image_seq = image_seq;
798 si->image_seq_set = 1;
799 } else if (ubi->image_seq && ubi->image_seq != image_seq) {
800 ubi_err("bad image sequence number %d in PEB %d, "
801 "expected %d", image_seq, pnum, ubi->image_seq);
802 ubi_dbg_dump_ec_hdr(ech);
808 /* OK, we've done with the EC header, let's look at the VID header */
810 err = ubi_io_read_vid_hdr(ubi, pnum, vidh, 0);
813 else if (err == UBI_IO_BITFLIPS)
815 else if (err == UBI_IO_BAD_VID_HDR ||
816 (err == UBI_IO_PEB_FREE && ec_corr)) {
817 /* VID header is corrupted */
818 err = add_to_list(si, pnum, ec, &si->corr);
822 } else if (err == UBI_IO_PEB_FREE) {
823 /* No VID header - the physical eraseblock is free */
824 err = add_to_list(si, pnum, ec, &si->free);
830 vol_id = be32_to_cpu(vidh->vol_id);
831 if (vol_id > UBI_MAX_VOLUMES && vol_id != UBI_LAYOUT_VOLUME_ID) {
832 int lnum = be32_to_cpu(vidh->lnum);
834 /* Unsupported internal volume */
835 switch (vidh->compat) {
836 case UBI_COMPAT_DELETE:
837 ubi_msg("\"delete\" compatible internal volume %d:%d"
838 " found, remove it", vol_id, lnum);
839 err = add_to_list(si, pnum, ec, &si->corr);
845 ubi_msg("read-only compatible internal volume %d:%d"
846 " found, switch to read-only mode",
851 case UBI_COMPAT_PRESERVE:
852 ubi_msg("\"preserve\" compatible internal volume %d:%d"
853 " found", vol_id, lnum);
854 err = add_to_list(si, pnum, ec, &si->alien);
857 si->alien_peb_count += 1;
860 case UBI_COMPAT_REJECT:
861 ubi_err("incompatible internal volume %d:%d found",
868 ubi_warn("valid VID header but corrupted EC header at PEB %d",
870 err = ubi_scan_add_used(ubi, si, pnum, ec, vidh, bitflips);
888 * ubi_scan - scan an MTD device.
889 * @ubi: UBI device description object
891 * This function does full scanning of an MTD device and returns complete
892 * information about it. In case of failure, an error code is returned.
894 struct ubi_scan_info *ubi_scan(struct ubi_device *ubi)
897 struct rb_node *rb1, *rb2;
898 struct ubi_scan_volume *sv;
899 struct ubi_scan_leb *seb;
900 struct ubi_scan_info *si;
902 si = kzalloc(sizeof(struct ubi_scan_info), GFP_KERNEL);
904 return ERR_PTR(-ENOMEM);
906 INIT_LIST_HEAD(&si->corr);
907 INIT_LIST_HEAD(&si->free);
908 INIT_LIST_HEAD(&si->erase);
909 INIT_LIST_HEAD(&si->alien);
910 si->volumes = RB_ROOT;
914 ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
918 vidh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
922 for (pnum = 0; pnum < ubi->peb_count; pnum++) {
925 dbg_gen("process PEB %d", pnum);
926 err = process_eb(ubi, si, pnum);
931 dbg_msg("scanning is finished");
933 /* Calculate mean erase counter */
935 si->mean_ec = div_u64(si->ec_sum, si->ec_count);
938 ubi_msg("empty MTD device detected");
941 * In case of unknown erase counter we use the mean erase counter
944 ubi_rb_for_each_entry(rb1, sv, &si->volumes, rb) {
945 ubi_rb_for_each_entry(rb2, seb, &sv->root, u.rb)
946 if (seb->ec == UBI_SCAN_UNKNOWN_EC)
947 seb->ec = si->mean_ec;
950 list_for_each_entry(seb, &si->free, u.list) {
951 if (seb->ec == UBI_SCAN_UNKNOWN_EC)
952 seb->ec = si->mean_ec;
955 list_for_each_entry(seb, &si->corr, u.list)
956 if (seb->ec == UBI_SCAN_UNKNOWN_EC)
957 seb->ec = si->mean_ec;
959 list_for_each_entry(seb, &si->erase, u.list)
960 if (seb->ec == UBI_SCAN_UNKNOWN_EC)
961 seb->ec = si->mean_ec;
963 err = paranoid_check_si(ubi, si);
970 ubi_free_vid_hdr(ubi, vidh);
976 ubi_free_vid_hdr(ubi, vidh);
980 ubi_scan_destroy_si(si);
985 * destroy_sv - free the scanning volume information
986 * @sv: scanning volume information
988 * This function destroys the volume RB-tree (@sv->root) and the scanning
989 * volume information.
991 static void destroy_sv(struct ubi_scan_volume *sv)
993 struct ubi_scan_leb *seb;
994 struct rb_node *this = sv->root.rb_node;
998 this = this->rb_left;
999 else if (this->rb_right)
1000 this = this->rb_right;
1002 seb = rb_entry(this, struct ubi_scan_leb, u.rb);
1003 this = rb_parent(this);
1005 if (this->rb_left == &seb->u.rb)
1006 this->rb_left = NULL;
1008 this->rb_right = NULL;
1018 * ubi_scan_destroy_si - destroy scanning information.
1019 * @si: scanning information
1021 void ubi_scan_destroy_si(struct ubi_scan_info *si)
1023 struct ubi_scan_leb *seb, *seb_tmp;
1024 struct ubi_scan_volume *sv;
1027 list_for_each_entry_safe(seb, seb_tmp, &si->alien, u.list) {
1028 list_del(&seb->u.list);
1031 list_for_each_entry_safe(seb, seb_tmp, &si->erase, u.list) {
1032 list_del(&seb->u.list);
1035 list_for_each_entry_safe(seb, seb_tmp, &si->corr, u.list) {
1036 list_del(&seb->u.list);
1039 list_for_each_entry_safe(seb, seb_tmp, &si->free, u.list) {
1040 list_del(&seb->u.list);
1044 /* Destroy the volume RB-tree */
1045 rb = si->volumes.rb_node;
1049 else if (rb->rb_right)
1052 sv = rb_entry(rb, struct ubi_scan_volume, rb);
1056 if (rb->rb_left == &sv->rb)
1059 rb->rb_right = NULL;
1069 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
1072 * paranoid_check_si - check the scanning information.
1073 * @ubi: UBI device description object
1074 * @si: scanning information
1076 * This function returns zero if the scanning information is all right, %1 if
1077 * not and a negative error code if an error occurred.
1079 static int paranoid_check_si(struct ubi_device *ubi, struct ubi_scan_info *si)
1081 int pnum, err, vols_found = 0;
1082 struct rb_node *rb1, *rb2;
1083 struct ubi_scan_volume *sv;
1084 struct ubi_scan_leb *seb, *last_seb;
1088 * At first, check that scanning information is OK.
1090 ubi_rb_for_each_entry(rb1, sv, &si->volumes, rb) {
1098 ubi_err("bad is_empty flag");
1102 if (sv->vol_id < 0 || sv->highest_lnum < 0 ||
1103 sv->leb_count < 0 || sv->vol_type < 0 || sv->used_ebs < 0 ||
1104 sv->data_pad < 0 || sv->last_data_size < 0) {
1105 ubi_err("negative values");
1109 if (sv->vol_id >= UBI_MAX_VOLUMES &&
1110 sv->vol_id < UBI_INTERNAL_VOL_START) {
1111 ubi_err("bad vol_id");
1115 if (sv->vol_id > si->highest_vol_id) {
1116 ubi_err("highest_vol_id is %d, but vol_id %d is there",
1117 si->highest_vol_id, sv->vol_id);
1121 if (sv->vol_type != UBI_DYNAMIC_VOLUME &&
1122 sv->vol_type != UBI_STATIC_VOLUME) {
1123 ubi_err("bad vol_type");
1127 if (sv->data_pad > ubi->leb_size / 2) {
1128 ubi_err("bad data_pad");
1133 ubi_rb_for_each_entry(rb2, seb, &sv->root, u.rb) {
1139 if (seb->pnum < 0 || seb->ec < 0) {
1140 ubi_err("negative values");
1144 if (seb->ec < si->min_ec) {
1145 ubi_err("bad si->min_ec (%d), %d found",
1146 si->min_ec, seb->ec);
1150 if (seb->ec > si->max_ec) {
1151 ubi_err("bad si->max_ec (%d), %d found",
1152 si->max_ec, seb->ec);
1156 if (seb->pnum >= ubi->peb_count) {
1157 ubi_err("too high PEB number %d, total PEBs %d",
1158 seb->pnum, ubi->peb_count);
1162 if (sv->vol_type == UBI_STATIC_VOLUME) {
1163 if (seb->lnum >= sv->used_ebs) {
1164 ubi_err("bad lnum or used_ebs");
1168 if (sv->used_ebs != 0) {
1169 ubi_err("non-zero used_ebs");
1174 if (seb->lnum > sv->highest_lnum) {
1175 ubi_err("incorrect highest_lnum or lnum");
1180 if (sv->leb_count != leb_count) {
1181 ubi_err("bad leb_count, %d objects in the tree",
1191 if (seb->lnum != sv->highest_lnum) {
1192 ubi_err("bad highest_lnum");
1197 if (vols_found != si->vols_found) {
1198 ubi_err("bad si->vols_found %d, should be %d",
1199 si->vols_found, vols_found);
1203 /* Check that scanning information is correct */
1204 ubi_rb_for_each_entry(rb1, sv, &si->volumes, rb) {
1206 ubi_rb_for_each_entry(rb2, seb, &sv->root, u.rb) {
1213 err = ubi_io_read_vid_hdr(ubi, seb->pnum, vidh, 1);
1214 if (err && err != UBI_IO_BITFLIPS) {
1215 ubi_err("VID header is not OK (%d)", err);
1221 vol_type = vidh->vol_type == UBI_VID_DYNAMIC ?
1222 UBI_DYNAMIC_VOLUME : UBI_STATIC_VOLUME;
1223 if (sv->vol_type != vol_type) {
1224 ubi_err("bad vol_type");
1228 if (seb->sqnum != be64_to_cpu(vidh->sqnum)) {
1229 ubi_err("bad sqnum %llu", seb->sqnum);
1233 if (sv->vol_id != be32_to_cpu(vidh->vol_id)) {
1234 ubi_err("bad vol_id %d", sv->vol_id);
1238 if (sv->compat != vidh->compat) {
1239 ubi_err("bad compat %d", vidh->compat);
1243 if (seb->lnum != be32_to_cpu(vidh->lnum)) {
1244 ubi_err("bad lnum %d", seb->lnum);
1248 if (sv->used_ebs != be32_to_cpu(vidh->used_ebs)) {
1249 ubi_err("bad used_ebs %d", sv->used_ebs);
1253 if (sv->data_pad != be32_to_cpu(vidh->data_pad)) {
1254 ubi_err("bad data_pad %d", sv->data_pad);
1262 if (sv->highest_lnum != be32_to_cpu(vidh->lnum)) {
1263 ubi_err("bad highest_lnum %d", sv->highest_lnum);
1267 if (sv->last_data_size != be32_to_cpu(vidh->data_size)) {
1268 ubi_err("bad last_data_size %d", sv->last_data_size);
1274 * Make sure that all the physical eraseblocks are in one of the lists
1277 buf = kzalloc(ubi->peb_count, GFP_KERNEL);
1281 for (pnum = 0; pnum < ubi->peb_count; pnum++) {
1282 err = ubi_io_is_bad(ubi, pnum);
1290 ubi_rb_for_each_entry(rb1, sv, &si->volumes, rb)
1291 ubi_rb_for_each_entry(rb2, seb, &sv->root, u.rb)
1294 list_for_each_entry(seb, &si->free, u.list)
1297 list_for_each_entry(seb, &si->corr, u.list)
1300 list_for_each_entry(seb, &si->erase, u.list)
1303 list_for_each_entry(seb, &si->alien, u.list)
1307 for (pnum = 0; pnum < ubi->peb_count; pnum++)
1309 ubi_err("PEB %d is not referred", pnum);
1319 ubi_err("bad scanning information about LEB %d", seb->lnum);
1320 ubi_dbg_dump_seb(seb, 0);
1321 ubi_dbg_dump_sv(sv);
1325 ubi_err("bad scanning information about volume %d", sv->vol_id);
1326 ubi_dbg_dump_sv(sv);
1330 ubi_err("bad scanning information about volume %d", sv->vol_id);
1331 ubi_dbg_dump_sv(sv);
1332 ubi_dbg_dump_vid_hdr(vidh);
1335 ubi_dbg_dump_stack();
1339 #endif /* CONFIG_MTD_UBI_DEBUG_PARANOID */