diff options
Diffstat (limited to 'fs/ubifs/recovery.c')
-rw-r--r-- | fs/ubifs/recovery.c | 57 |
1 files changed, 33 insertions, 24 deletions
diff --git a/fs/ubifs/recovery.c b/fs/ubifs/recovery.c index 805605250f12..e5f6cf8a1155 100644 --- a/fs/ubifs/recovery.c +++ b/fs/ubifs/recovery.c @@ -53,6 +53,25 @@ static int is_empty(void *buf, int len) } /** + * first_non_ff - find offset of the first non-0xff byte. + * @buf: buffer to search in + * @len: length of buffer + * + * This function returns offset of the first non-0xff byte in @buf or %-1 if + * the buffer contains only 0xff bytes. + */ +static int first_non_ff(void *buf, int len) +{ + uint8_t *p = buf; + int i; + + for (i = 0; i < len; i++) + if (*p++ != 0xff) + return i; + return -1; +} + +/** * get_master_node - get the last valid master node allowing for corruption. * @c: UBIFS file-system description object * @lnum: LEB number @@ -357,11 +376,7 @@ static int is_last_write(const struct ubifs_info *c, void *buf, int offs) empty_offs = ALIGN(offs + 1, c->min_io_size); check_len = c->leb_size - empty_offs; p = buf + empty_offs - offs; - - for (; check_len > 0; check_len--) - if (*p++ != 0xff) - return 0; - return 1; + return is_empty(p, check_len); } /** @@ -543,8 +558,8 @@ static int drop_incomplete_group(struct ubifs_scan_leb *sleb, int *offs) * * This function does a scan of a LEB, but caters for errors that might have * been caused by the unclean unmount from which we are attempting to recover. - * - * This function returns %0 on success and a negative error code on failure. + * Returns %0 in case of success, %-EUCLEAN if an unrecoverable corruption is + * found, and a negative error code in case of failure. */ struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum, int offs, void *sbuf, int grouped) @@ -643,7 +658,8 @@ struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum, goto corrupted; default: dbg_err("unknown"); - goto corrupted; + err = -EINVAL; + goto error; } } @@ -652,8 +668,13 @@ struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum, clean_buf(c, &buf, lnum, &offs, &len); need_clean = 1; } else { - ubifs_err("corrupt empty space at LEB %d:%d", - lnum, offs); + int corruption = first_non_ff(buf, len); + + ubifs_err("corrupt empty space LEB %d:%d, corruption " + "starts at %d", lnum, offs, corruption); + /* Make sure we dump interesting non-0xFF data */ + offs = corruption; + buf += corruption; goto corrupted; } } @@ -813,7 +834,7 @@ struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum, static int recover_head(const struct ubifs_info *c, int lnum, int offs, void *sbuf) { - int len, err, need_clean = 0; + int len, err; if (c->min_io_size > 1) len = c->min_io_size; @@ -827,19 +848,7 @@ static int recover_head(const struct ubifs_info *c, int lnum, int offs, /* Read at the head location and check it is empty flash */ err = ubi_read(c->ubi, lnum, sbuf, offs, len); - if (err) - need_clean = 1; - else { - uint8_t *p = sbuf; - - while (len--) - if (*p++ != 0xff) { - need_clean = 1; - break; - } - } - - if (need_clean) { + if (err || !is_empty(sbuf, len)) { dbg_rcvry("cleaning head at %d:%d", lnum, offs); if (offs == 0) return ubifs_leb_unmap(c, lnum); |