diff options
Diffstat (limited to 'drivers/mtd')
| -rw-r--r-- | drivers/mtd/ubi/attach.c | 28 | ||||
| -rw-r--r-- | drivers/mtd/ubi/ubi.h | 3 |
2 files changed, 27 insertions, 4 deletions
diff --git a/drivers/mtd/ubi/attach.c b/drivers/mtd/ubi/attach.c index bd6fc528b10a..903becd31410 100644 --- a/drivers/mtd/ubi/attach.c +++ b/drivers/mtd/ubi/attach.c @@ -856,13 +856,15 @@ static bool vol_ignored(int vol_id) * @ubi: UBI device description object * @ai: attaching information * @pnum: the physical eraseblock number + * @fast: true if we're scanning for a Fastmap * * This function reads UBI headers of PEB @pnum, checks them, and adds * information about this PEB to the corresponding list or RB-tree in the * "attaching info" structure. Returns zero if the physical eraseblock was * successfully handled and a negative error code in case of failure. */ -static int scan_peb(struct ubi_device *ubi, struct ubi_attach_info *ai, int pnum) +static int scan_peb(struct ubi_device *ubi, struct ubi_attach_info *ai, + int pnum, bool fast) { long long ec; int err, bitflips = 0, vol_id = -1, ec_err = 0; @@ -980,6 +982,20 @@ static int scan_peb(struct ubi_device *ubi, struct ubi_attach_info *ai, int pnum */ ai->maybe_bad_peb_count += 1; case UBI_IO_BAD_HDR: + /* + * If we're facing a bad VID header we have to drop *all* + * Fastmap data structures we find. The most recent Fastmap + * could be bad and therefore there is a chance that we attach + * from an old one. On a fine MTD stack a PEB must not render + * bad all of a sudden, but the reality is different. + * So, let's be paranoid and help finding the root cause by + * falling back to scanning mode instead of attaching with a + * bad EBA table and cause data corruption which is hard to + * analyze. + */ + if (fast) + ai->force_full_scan = 1; + if (ec_err) /* * Both headers are corrupted. There is a possibility @@ -1293,7 +1309,7 @@ static int scan_all(struct ubi_device *ubi, struct ubi_attach_info *ai, cond_resched(); dbg_gen("process PEB %d", pnum); - err = scan_peb(ubi, ai, pnum); + err = scan_peb(ubi, ai, pnum, false); if (err < 0) goto out_vidh; } @@ -1407,7 +1423,7 @@ static int scan_fast(struct ubi_device *ubi, struct ubi_attach_info **ai) cond_resched(); dbg_gen("process PEB %d", pnum); - err = scan_peb(ubi, scan_ai, pnum); + err = scan_peb(ubi, scan_ai, pnum, true); if (err < 0) goto out_vidh; } @@ -1415,7 +1431,11 @@ static int scan_fast(struct ubi_device *ubi, struct ubi_attach_info **ai) ubi_free_vid_hdr(ubi, vidh); kfree(ech); - err = ubi_scan_fastmap(ubi, *ai, scan_ai); + if (scan_ai->force_full_scan) + err = UBI_NO_FASTMAP; + else + err = ubi_scan_fastmap(ubi, *ai, scan_ai); + if (err) { /* * Didn't attach via fastmap, do a full scan but reuse what diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h index c8b90a866d27..b616a115c9d3 100644 --- a/drivers/mtd/ubi/ubi.h +++ b/drivers/mtd/ubi/ubi.h @@ -715,6 +715,8 @@ struct ubi_ainf_volume { * @vols_found: number of volumes found * @highest_vol_id: highest volume ID * @is_empty: flag indicating whether the MTD device is empty or not + * @force_full_scan: flag indicating whether we need to do a full scan and drop + all existing Fastmap data structures * @min_ec: lowest erase counter value * @max_ec: highest erase counter value * @max_sqnum: highest sequence number value @@ -742,6 +744,7 @@ struct ubi_attach_info { int vols_found; int highest_vol_id; int is_empty; + int force_full_scan; int min_ec; int max_ec; unsigned long long max_sqnum; |