[PATCH] UBIFS: optionally return partial LEB scan results
Matthew L. Creech
mlcreech at gmail.com
Tue Jun 7 16:52:47 EDT 2011
ubifs_scan() currently returns -EUCLEAN when it encounters corrupted data
while scanning a LEB. This is usually the right thing to do, but it prevents
us from debugging certain kinds of corruption, since ubifs_scan() is called
from dbg_dump_leb().
Add a flag which makes ubifs_scan() return partial node data when corruption
is encountered, and use that flag in dbg_dump_leb().
Signed-off-by: Matthew L. Creech <mlcreech at gmail.com>
---
fs/ubifs/debug.c | 2 +-
fs/ubifs/gc.c | 2 +-
fs/ubifs/log.c | 2 +-
fs/ubifs/lprops.c | 2 +-
fs/ubifs/master.c | 4 ++--
fs/ubifs/orphan.c | 4 ++--
fs/ubifs/recovery.c | 2 +-
fs/ubifs/replay.c | 4 ++--
fs/ubifs/scan.c | 16 ++++++++++++----
fs/ubifs/tnc_commit.c | 2 +-
fs/ubifs/ubifs.h | 2 +-
11 files changed, 25 insertions(+), 17 deletions(-)
diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
index 26d4c61..d6239d2 100644
--- a/fs/ubifs/debug.c
+++ b/fs/ubifs/debug.c
@@ -898,7 +898,7 @@ void dbg_dump_leb(const struct ubifs_info *c, int lnum)
return;
}
- sleb = ubifs_scan(c, lnum, 0, buf, 0);
+ sleb = ubifs_scan(c, lnum, 0, buf, 0, 1);
if (IS_ERR(sleb)) {
ubifs_err("scan error %d", (int)PTR_ERR(sleb));
goto out;
diff --git a/fs/ubifs/gc.c b/fs/ubifs/gc.c
index ded29f6..5266dc6 100644
--- a/fs/ubifs/gc.c
+++ b/fs/ubifs/gc.c
@@ -513,7 +513,7 @@ int ubifs_garbage_collect_leb(struct ubifs_info *c, struct ubifs_lprops *lp)
* We scan the entire LEB even though we only really need to scan up to
* (c->leb_size - lp->free).
*/
- sleb = ubifs_scan(c, lnum, 0, c->sbuf, 0);
+ sleb = ubifs_scan(c, lnum, 0, c->sbuf, 0, 0);
if (IS_ERR(sleb))
return PTR_ERR(sleb);
diff --git a/fs/ubifs/log.c b/fs/ubifs/log.c
index affea94..472aff6 100644
--- a/fs/ubifs/log.c
+++ b/fs/ubifs/log.c
@@ -662,7 +662,7 @@ int ubifs_consolidate_log(struct ubifs_info *c)
lnum = c->ltail_lnum;
write_lnum = lnum;
while (1) {
- sleb = ubifs_scan(c, lnum, 0, c->sbuf, 0);
+ sleb = ubifs_scan(c, lnum, 0, c->sbuf, 0, 0);
if (IS_ERR(sleb)) {
err = PTR_ERR(sleb);
goto out_free;
diff --git a/fs/ubifs/lprops.c b/fs/ubifs/lprops.c
index 98b8e73..2384463 100644
--- a/fs/ubifs/lprops.c
+++ b/fs/ubifs/lprops.c
@@ -1105,7 +1105,7 @@ static int scan_check_cb(struct ubifs_info *c,
return LPT_SCAN_CONTINUE;
}
- sleb = ubifs_scan(c, lnum, 0, buf, 0);
+ sleb = ubifs_scan(c, lnum, 0, buf, 0, 0);
if (IS_ERR(sleb)) {
ret = PTR_ERR(sleb);
if (ret == -EUCLEAN) {
diff --git a/fs/ubifs/master.c b/fs/ubifs/master.c
index 278c238..8b86712 100644
--- a/fs/ubifs/master.c
+++ b/fs/ubifs/master.c
@@ -41,7 +41,7 @@ static int scan_for_master(struct ubifs_info *c)
lnum = UBIFS_MST_LNUM;
- sleb = ubifs_scan(c, lnum, 0, c->sbuf, 1);
+ sleb = ubifs_scan(c, lnum, 0, c->sbuf, 1, 0);
if (IS_ERR(sleb))
return PTR_ERR(sleb);
nodes_cnt = sleb->nodes_cnt;
@@ -57,7 +57,7 @@ static int scan_for_master(struct ubifs_info *c)
lnum += 1;
- sleb = ubifs_scan(c, lnum, 0, c->sbuf, 1);
+ sleb = ubifs_scan(c, lnum, 0, c->sbuf, 1, 0);
if (IS_ERR(sleb))
return PTR_ERR(sleb);
if (sleb->nodes_cnt != nodes_cnt)
diff --git a/fs/ubifs/orphan.c b/fs/ubifs/orphan.c
index a5422ff..76fba30 100644
--- a/fs/ubifs/orphan.c
+++ b/fs/ubifs/orphan.c
@@ -670,7 +670,7 @@ static int kill_orphans(struct ubifs_info *c)
struct ubifs_scan_leb *sleb;
dbg_rcvry("LEB %d", lnum);
- sleb = ubifs_scan(c, lnum, 0, c->sbuf, 1);
+ sleb = ubifs_scan(c, lnum, 0, c->sbuf, 1, 0);
if (IS_ERR(sleb)) {
if (PTR_ERR(sleb) == -EUCLEAN)
sleb = ubifs_recover_leb(c, lnum, 0,
@@ -908,7 +908,7 @@ static int dbg_scan_orphans(struct ubifs_info *c, struct check_info *ci)
for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
struct ubifs_scan_leb *sleb;
- sleb = ubifs_scan(c, lnum, 0, buf, 0);
+ sleb = ubifs_scan(c, lnum, 0, buf, 0, 0);
if (IS_ERR(sleb)) {
err = PTR_ERR(sleb);
break;
diff --git a/fs/ubifs/recovery.c b/fs/ubifs/recovery.c
index 783d8e0..2456dd0 100644
--- a/fs/ubifs/recovery.c
+++ b/fs/ubifs/recovery.c
@@ -878,7 +878,7 @@ struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum,
* We can only recover at the end of the log, so check that the
* next log LEB is empty or out of date.
*/
- sleb = ubifs_scan(c, next_lnum, 0, sbuf, 0);
+ sleb = ubifs_scan(c, next_lnum, 0, sbuf, 0, 0);
if (IS_ERR(sleb))
return sleb;
if (sleb->nodes_cnt) {
diff --git a/fs/ubifs/replay.c b/fs/ubifs/replay.c
index 5e97161..53eb2bb 100644
--- a/fs/ubifs/replay.c
+++ b/fs/ubifs/replay.c
@@ -559,7 +559,7 @@ static int replay_bud(struct ubifs_info *c, struct bud_entry *b)
*/
sleb = ubifs_recover_leb(c, lnum, offs, c->sbuf, b->bud->jhead);
else
- sleb = ubifs_scan(c, lnum, offs, c->sbuf, 0);
+ sleb = ubifs_scan(c, lnum, offs, c->sbuf, 0, 0);
if (IS_ERR(sleb))
return PTR_ERR(sleb);
@@ -832,7 +832,7 @@ static int replay_log_leb(struct ubifs_info *c, int lnum, int offs, void *sbuf)
const struct ubifs_cs_node *node;
dbg_mnt("replay log LEB %d:%d", lnum, offs);
- sleb = ubifs_scan(c, lnum, offs, sbuf, c->need_recovery);
+ sleb = ubifs_scan(c, lnum, offs, sbuf, c->need_recovery, 0);
if (IS_ERR(sleb)) {
if (PTR_ERR(sleb) != -EUCLEAN || !c->need_recovery)
return PTR_ERR(sleb);
diff --git a/fs/ubifs/scan.c b/fs/ubifs/scan.c
index 36216b4..3f70d47 100644
--- a/fs/ubifs/scan.c
+++ b/fs/ubifs/scan.c
@@ -256,17 +256,21 @@ void ubifs_scanned_corruption(const struct ubifs_info *c, int lnum, int offs,
* @offs: offset to start at (usually zero)
* @sbuf: scan buffer (must be of @c->leb_size bytes in size)
* @quiet: print no messages
+ * @partial: return partial results when corruption is encountered (vs. error)
*
* This function scans LEB number @lnum and returns complete information about
- * its contents. Returns the scaned information in case of success and,
- * %-EUCLEAN if the LEB neads recovery, and other negative error codes in case
- * of failure.
+ * its contents. Returns the scaned information in case of success,
+ * %-EUCLEAN if the LEB neads recovery (and @partial is not set), and other
+ * negative error codes in case of failure.
*
* If @quiet is non-zero, this function does not print large and scary
* error messages and flash dumps in case of errors.
+ *
+ * If @partial is non-zero, this function returns partial scan data if the LEB
+ * is corrupt. This can be useful for debugging.
*/
struct ubifs_scan_leb *ubifs_scan(const struct ubifs_info *c, int lnum,
- int offs, void *sbuf, int quiet)
+ int offs, void *sbuf, int quiet, int partial)
{
void *buf = sbuf + offs;
int err, len = c->leb_size - offs;
@@ -352,6 +356,10 @@ corrupted:
ubifs_err("LEB %d scanning failed", lnum);
}
err = -EUCLEAN;
+ if (partial) {
+ dbg_err("returning partial results for %d:%d", lnum, offs);
+ return sleb;
+ }
ubifs_scan_destroy(sleb);
return ERR_PTR(err);
diff --git a/fs/ubifs/tnc_commit.c b/fs/ubifs/tnc_commit.c
index d6fab1a..f831abd 100644
--- a/fs/ubifs/tnc_commit.c
+++ b/fs/ubifs/tnc_commit.c
@@ -249,7 +249,7 @@ static int layout_leb_in_gaps(struct ubifs_info *c, int *p)
* it is more comprehensive and less efficient than is needed for this
* purpose.
*/
- sleb = ubifs_scan(c, lnum, 0, c->ileb_buf, 0);
+ sleb = ubifs_scan(c, lnum, 0, c->ileb_buf, 0, 0);
c->ileb_len = 0;
if (IS_ERR(sleb))
return PTR_ERR(sleb);
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 3304aad..dfa5012 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -1491,7 +1491,7 @@ int ubifs_sync_wbufs_by_inode(struct ubifs_info *c, struct inode *inode);
/* scan.c */
struct ubifs_scan_leb *ubifs_scan(const struct ubifs_info *c, int lnum,
- int offs, void *sbuf, int quiet);
+ int offs, void *sbuf, int quiet, int partial);
void ubifs_scan_destroy(struct ubifs_scan_leb *sleb);
int ubifs_scan_a_node(const struct ubifs_info *c, void *buf, int len, int lnum,
int offs, int quiet);
--
1.6.3.3
More information about the linux-mtd
mailing list