9  * UBI attaching sub-system.
32  * UBI protects EC and VID headers with CRC-32 checksums, so it can detect
33  * whether the headers are corrupted or not. Sometimes UBI also protects the
37  * UBI tries to distinguish between 2 types of corruptions.
39  * 1. Corruptions caused by power cuts. These are expected corruptions and UBI
46  * When UBI detects a corruption (CRC-32 mismatch) in a PEB, and it looks like
47  * the reason is a power cut, UBI puts this PEB to the @erase list, and all
51  * attaching, such PEBs are put to the @corr list and UBI preserves them.
53  * UBI runs out of free PEBs, it switches to R/O mode. UBI also loudly informs
57  * corruptions and UBI's strategy is as follows (in case of attaching by
58  * scanning). UBI assumes corruption type 2 if the VID header is corrupted and
61  * area.  Otherwise UBI assumes corruption type 1. So the decision criteria
77 #include "ubi.h"
79 static int self_check_ai(struct ubi_device *ubi, struct ubi_attach_info *ai);
317  * @ubi: UBI device description object
325  * Note, UBI does sanity check of everything it reads from the flash media.
330 static int validate_vid_hdr(const struct ubi_device *ubi,  in validate_vid_hdr()  argument
349 			ubi_err(ubi, "inconsistent vol_id");  in validate_vid_hdr()
359 			ubi_err(ubi, "inconsistent vol_type");  in validate_vid_hdr()
364 			ubi_err(ubi, "inconsistent used_ebs");  in validate_vid_hdr()
369 			ubi_err(ubi, "inconsistent data_pad");  in validate_vid_hdr()
377 	ubi_err(ubi, "inconsistent VID header at PEB %d", pnum);  in validate_vid_hdr()
420  * @ubi: UBI device description object
438 int ubi_compare_lebs(struct ubi_device *ubi, const struct ubi_ainf_peb *aeb,  in ubi_compare_lebs()  argument
448 		 * This must be a really ancient UBI image which has been  in ubi_compare_lebs()
451 		 * eraseblocks. That was before UBI got into mainline. We do not  in ubi_compare_lebs()
455 		ubi_err(ubi, "unsupported on-flash UBI format");  in ubi_compare_lebs()
486 		vidb = ubi_alloc_vid_buf(ubi, GFP_KERNEL);  in ubi_compare_lebs()
491 		err = ubi_io_read_vid_hdr(ubi, pnum, vidb, 0);  in ubi_compare_lebs()
496 				ubi_err(ubi, "VID of PEB %d header is bad, but it was OK earlier, err %d",  in ubi_compare_lebs()
512 	mutex_lock(&ubi->buf_mutex);  in ubi_compare_lebs()
513 	err = ubi_io_read_data(ubi, ubi->peb_buf, pnum, 0, len);  in ubi_compare_lebs()
518 	crc = crc32(UBI_CRC32_INIT, ubi->peb_buf, len);  in ubi_compare_lebs()
529 	mutex_unlock(&ubi->buf_mutex);  in ubi_compare_lebs()
541 	mutex_unlock(&ubi->buf_mutex);  in ubi_compare_lebs()
549  * @ubi: UBI device description object
563 int ubi_add_to_av(struct ubi_device *ubi, struct ubi_attach_info *ai, int pnum,  in ubi_add_to_av()  argument
617 		 * be an ancient UBI image from the era when UBI did not have  in ubi_add_to_av()
626 			ubi_err(ubi, "two LEBs with same sequence number %llu",  in ubi_add_to_av()
637 		cmp_res = ubi_compare_lebs(ubi, aeb, pnum, vid_hdr);  in ubi_add_to_av()
646 			err = validate_vid_hdr(ubi, vid_hdr, av, pnum);  in ubi_add_to_av()
684 	err = validate_vid_hdr(ubi, vid_hdr, av, pnum);  in ubi_add_to_av()
760  * @ubi: UBI device description object
766  * counter header to it. This function should only be used on UBI device
771 static int early_erase_peb(struct ubi_device *ubi,  in early_erase_peb()  argument
779 		 * Erase counter overflow. Upgrade UBI and use 64-bit  in early_erase_peb()
782 		ubi_err(ubi, "erase counter overflow at PEB %d, EC %d",  in early_erase_peb()
787 	ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);  in early_erase_peb()
793 	err = ubi_io_sync_erase(ubi, pnum, 0);  in early_erase_peb()
797 	err = ubi_io_write_ec_hdr(ubi, pnum, ec_hdr);  in early_erase_peb()
806  * @ubi: UBI device description object
810  * called on the UBI initialization stages when the wear-leveling sub-system is
818 struct ubi_ainf_peb *ubi_early_get_peb(struct ubi_device *ubi,  in ubi_early_get_peb()  argument
841 		err = early_erase_peb(ubi, ai, aeb->pnum, aeb->ec+1);  in ubi_early_get_peb()
851 	ubi_err(ubi, "no free eraseblocks");  in ubi_early_get_peb()
857  * @ubi: UBI device description object
868  * If the corruption reason was a power cut, UBI can safely erase this PEB.
872 static int check_corruption(struct ubi_device *ubi, struct ubi_vid_hdr *vid_hdr,  in check_corruption()  argument
877 	mutex_lock(&ubi->buf_mutex);  in check_corruption()
878 	memset(ubi->peb_buf, 0x00, ubi->leb_size);  in check_corruption()
880 	err = ubi_io_read(ubi, ubi->peb_buf, pnum, ubi->leb_start,  in check_corruption()
881 			  ubi->leb_size);  in check_corruption()
897 	if (ubi_check_pattern(ubi->peb_buf, 0xFF, ubi->leb_size))  in check_corruption()
900 	ubi_err(ubi, "PEB %d contains corrupted VID header, and the data does not contain all 0xFF",  in check_corruption()
902 …ubi_err(ubi, "this may be a non-UBI PEB or a severe VID header corruption which requires manual in…  in check_corruption()
905 	       pnum, ubi->leb_start, ubi->leb_size);  in check_corruption()
907 			       ubi->peb_buf, ubi->leb_size, 1);  in check_corruption()
911 	mutex_unlock(&ubi->buf_mutex);  in check_corruption()
930  * scan_peb - scan and process UBI headers of a PEB.
931  * @ubi: UBI device description object
936  * This function reads UBI headers of PEB @pnum, checks them, and adds
941 static int scan_peb(struct ubi_device *ubi, struct ubi_attach_info *ai,  in scan_peb()  argument
953 	err = ubi_io_is_bad(ubi, pnum);  in scan_peb()
961 	err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);  in scan_peb()
990 		ubi_err(ubi, "'ubi_io_read_ec_hdr()' returned unknown code %d",  in scan_peb()
998 		/* Make sure UBI version is OK */  in scan_peb()
1000 			ubi_err(ubi, "this UBI version is %d, image version is %d",  in scan_peb()
1011 			 * flash. Upgrade UBI and use 64-bit erase counters  in scan_peb()
1014 			ubi_err(ubi, "erase counter overflow, max is %d",  in scan_peb()
1022 		 * This allows us to detect situations when users flash UBI  in scan_peb()
1023 		 * images incorrectly, so that the flash has the new UBI image  in scan_peb()
1026 		 * zero, because old UBI implementations always set it to zero.  in scan_peb()
1032 		if (!ubi->image_seq)  in scan_peb()
1033 			ubi->image_seq = image_seq;  in scan_peb()
1034 		if (image_seq && ubi->image_seq != image_seq) {  in scan_peb()
1035 			ubi_err(ubi, "bad image sequence number %d in PEB %d, expected %d",  in scan_peb()
1036 				image_seq, pnum, ubi->image_seq);  in scan_peb()
1044 	err = ubi_io_read_vid_hdr(ubi, pnum, vidb, 0);  in scan_peb()
1081 			 * that this a valid UBI PEB which has corresponding  in scan_peb()
1097 			err = check_corruption(ubi, vidh, pnum);  in scan_peb()
1128 		ubi_err(ubi, "'ubi_io_read_vid_hdr()' returned unknown code %d",  in scan_peb()
1140 			ubi_msg(ubi, "\"delete\" compatible internal volume %d:%d found, will remove it",  in scan_peb()
1150 			ubi_msg(ubi, "read-only compatible internal volume %d:%d found, switch to read-only mode",  in scan_peb()
1152 			ubi->ro_mode = 1;  in scan_peb()
1156 			ubi_msg(ubi, "\"preserve\" compatible internal volume %d:%d found",  in scan_peb()
1165 			ubi_err(ubi, "incompatible internal volume %d:%d found",  in scan_peb()
1172 		ubi_warn(ubi, "valid VID header but corrupted EC header at PEB %d",  in scan_peb()
1178 		err = ubi_add_to_av(ubi, ai, pnum, ec, vidh, bitflips);  in scan_peb()
1198  * @ubi: UBI device description object
1207 static int late_analysis(struct ubi_device *ubi, struct ubi_attach_info *ai)  in late_analysis()  argument
1212 	peb_count = ubi->peb_count - ai->bad_peb_count - ai->alien_peb_count;  in late_analysis()
1221 		ubi_err(ubi, "%d PEBs are corrupted and preserved",  in late_analysis()
1233 			ubi_err(ubi, "too many corrupted PEBs, refusing");  in late_analysis()
1251 		 * 2. Flash contains non-UBI data and we do not want to format  in late_analysis()
1256 			ubi_msg(ubi, "empty MTD device detected");  in late_analysis()
1257 			get_random_bytes(&ubi->image_seq,  in late_analysis()
1258 					 sizeof(ubi->image_seq));  in late_analysis()
1260 			ubi_err(ubi, "MTD device is not UBI-formatted and possibly contains non-UBI data - refusing it");  in late_analysis()
1366  * @ubi: UBI device description object
1374 static int scan_all(struct ubi_device *ubi, struct ubi_attach_info *ai,  in scan_all()  argument
1384 	ai->ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);  in scan_all()
1388 	ai->vidb = ubi_alloc_vid_buf(ubi, GFP_KERNEL);  in scan_all()
1392 	for (pnum = start; pnum < ubi->peb_count; pnum++) {  in scan_all()
1396 		err = scan_peb(ubi, ai, pnum, false);  in scan_all()
1401 	ubi_msg(ubi, "scanning is finished");  in scan_all()
1407 	err = late_analysis(ubi, ai);  in scan_all()
1434 	err = self_check_ai(ubi, ai);  in scan_all()
1479  * @ubi: UBI device description object
1487 static int scan_fast(struct ubi_device *ubi, struct ubi_attach_info **ai)  in scan_fast()  argument
1498 	scan_ai->ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);  in scan_fast()
1502 	scan_ai->vidb = ubi_alloc_vid_buf(ubi, GFP_KERNEL);  in scan_fast()
1510 		err = scan_peb(ubi, scan_ai, pnum, true);  in scan_fast()
1521 		err = ubi_scan_fastmap(ubi, *ai, scan_ai);  in scan_fast()
1549  * @ubi: UBI device descriptor
1555 int ubi_attach(struct ubi_device *ubi, int force_scan)  in ubi_attach()  argument
1566 	if ((int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd) <= UBI_FM_MAX_START) {  in ubi_attach()
1567 		ubi->fm_disabled = 1;  in ubi_attach()
1572 		err = scan_all(ubi, ai, 0);  in ubi_attach()
1574 		err = scan_fast(ubi, &ai);  in ubi_attach()
1582 				err = scan_all(ubi, ai, 0);  in ubi_attach()
1584 				err = scan_all(ubi, ai, UBI_FM_MAX_START);  in ubi_attach()
1589 	err = scan_all(ubi, ai, 0);  in ubi_attach()
1594 	ubi->bad_peb_count = ai->bad_peb_count;  in ubi_attach()
1595 	ubi->good_peb_count = ubi->peb_count - ubi->bad_peb_count;  in ubi_attach()
1596 	ubi->corr_peb_count = ai->corr_peb_count;  in ubi_attach()
1597 	ubi->max_ec = ai->max_ec;  in ubi_attach()
1598 	ubi->mean_ec = ai->mean_ec;  in ubi_attach()
1601 	err = ubi_read_volume_table(ubi, ai);  in ubi_attach()
1605 	err = ubi_wl_init(ubi, ai);  in ubi_attach()
1609 	err = ubi_eba_init(ubi, ai);  in ubi_attach()
1614 	if (ubi->fm && ubi_dbg_chk_fastmap(ubi)) {  in ubi_attach()
1623 		err = scan_all(ubi, scan_ai, 0);  in ubi_attach()
1629 		err = self_check_eba(ubi, ai, scan_ai);  in ubi_attach()
1641 	ubi_wl_close(ubi);  in ubi_attach()
1643 	ubi_free_all_volumes(ubi);  in ubi_attach()
1644 	vfree(ubi->vtbl);  in ubi_attach()
1652  * @ubi: UBI device description object
1658 static int self_check_ai(struct ubi_device *ubi, struct ubi_attach_info *ai)  in self_check_ai()  argument
1668 	if (!ubi_dbg_chk_gen(ubi))  in self_check_ai()
1682 			ubi_err(ubi, "bad is_empty flag");  in self_check_ai()
1689 			ubi_err(ubi, "negative values");  in self_check_ai()
1695 			ubi_err(ubi, "bad vol_id");  in self_check_ai()
1700 			ubi_err(ubi, "highest_vol_id is %d, but vol_id %d is there",  in self_check_ai()
1707 			ubi_err(ubi, "bad vol_type");  in self_check_ai()
1711 		if (av->data_pad > ubi->leb_size / 2) {  in self_check_ai()
1712 			ubi_err(ubi, "bad data_pad");  in self_check_ai()
1724 				ubi_err(ubi, "negative values");  in self_check_ai()
1729 				ubi_err(ubi, "bad ai->min_ec (%d), %d found",  in self_check_ai()
1735 				ubi_err(ubi, "bad ai->max_ec (%d), %d found",  in self_check_ai()
1740 			if (aeb->pnum >= ubi->peb_count) {  in self_check_ai()
1741 				ubi_err(ubi, "too high PEB number %d, total PEBs %d",  in self_check_ai()
1742 					aeb->pnum, ubi->peb_count);  in self_check_ai()
1748 					ubi_err(ubi, "bad lnum or used_ebs");  in self_check_ai()
1753 					ubi_err(ubi, "non-zero used_ebs");  in self_check_ai()
1759 				ubi_err(ubi, "incorrect highest_lnum or lnum");  in self_check_ai()
1765 			ubi_err(ubi, "bad leb_count, %d objects in the tree",  in self_check_ai()
1776 			ubi_err(ubi, "bad highest_lnum");  in self_check_ai()
1782 		ubi_err(ubi, "bad ai->vols_found %d, should be %d",  in self_check_ai()
1797 			err = ubi_io_read_vid_hdr(ubi, aeb->pnum, vidb, 1);  in self_check_ai()
1799 				ubi_err(ubi, "VID header is not OK (%d)",  in self_check_ai()
1809 				ubi_err(ubi, "bad vol_type");  in self_check_ai()
1814 				ubi_err(ubi, "bad sqnum %llu", aeb->sqnum);  in self_check_ai()
1819 				ubi_err(ubi, "bad vol_id %d", av->vol_id);  in self_check_ai()
1824 				ubi_err(ubi, "bad compat %d", vidh->compat);  in self_check_ai()
1829 				ubi_err(ubi, "bad lnum %d", aeb->lnum);  in self_check_ai()
1834 				ubi_err(ubi, "bad used_ebs %d", av->used_ebs);  in self_check_ai()
1839 				ubi_err(ubi, "bad data_pad %d", av->data_pad);  in self_check_ai()
1848 			ubi_err(ubi, "bad highest_lnum %d", av->highest_lnum);  in self_check_ai()
1853 			ubi_err(ubi, "bad last_data_size %d",  in self_check_ai()
1863 	buf = kzalloc(ubi->peb_count, GFP_KERNEL);  in self_check_ai()
1867 	for (pnum = 0; pnum < ubi->peb_count; pnum++) {  in self_check_ai()
1868 		err = ubi_io_is_bad(ubi, pnum);  in self_check_ai()
1893 	for (pnum = 0; pnum < ubi->peb_count; pnum++)  in self_check_ai()
1895 			ubi_err(ubi, "PEB %d is not referred", pnum);  in self_check_ai()
1905 	ubi_err(ubi, "bad attaching information about LEB %d", aeb->lnum);  in self_check_ai()
1911 	ubi_err(ubi, "bad attaching information about volume %d", av->vol_id);  in self_check_ai()
1916 	ubi_err(ubi, "bad attaching information about volume %d", av->vol_id);  in self_check_ai()