Patchwork jffs2: don't fail on bitflips in OOB

login
register
mail settings
Submitter Brian Norris
Date Aug. 31, 2012, 10:01 p.m.
Message ID <1346450479-22400-1-git-send-email-computersforpeace@gmail.com>
Download mbox | patch
Permalink /patch/181062/
State New
Headers show

Comments

Brian Norris - Aug. 31, 2012, 10:01 p.m.
JFFS2 was designed without thought for OOB bitflips, it seems, but they
can occur and will be reported to JFFS2 via mtd_read_oob()[1]. We don't
want to fail on these transactions, since the data was corrected.

[1] Few drivers report bitflips for OOB-only transactions. With such
    drivers, this patch should have no effect.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: stable@vger.kernel.org
---
 fs/jffs2/wbuf.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)
Artem Bityutskiy - Sept. 4, 2012, 8:03 a.m.
On Fri, 2012-08-31 at 15:01 -0700, Brian Norris wrote:
> JFFS2 was designed without thought for OOB bitflips, it seems, but they
> can occur and will be reported to JFFS2 via mtd_read_oob()[1]. We don't
> want to fail on these transactions, since the data was corrected.
> 
> [1] Few drivers report bitflips for OOB-only transactions. With such
>     drivers, this patch should have no effect.
> 
> Signed-off-by: Brian Norris <computersforpeace@gmail.com>
> Cc: stable@vger.kernel.org

Pushed to l2-mtd.git, thanks!

Patch

diff --git a/fs/jffs2/wbuf.c b/fs/jffs2/wbuf.c
index 6f4529d..a6597d6 100644
--- a/fs/jffs2/wbuf.c
+++ b/fs/jffs2/wbuf.c
@@ -1044,10 +1044,10 @@  int jffs2_check_oob_empty(struct jffs2_sb_info *c,
 	ops.datbuf = NULL;
 
 	ret = mtd_read_oob(c->mtd, jeb->offset, &ops);
-	if (ret || ops.oobretlen != ops.ooblen) {
+	if ((ret && !mtd_is_bitflip(ret)) || ops.oobretlen != ops.ooblen) {
 		pr_err("cannot read OOB for EB at %08x, requested %zd bytes, read %zd bytes, error %d\n",
 		       jeb->offset, ops.ooblen, ops.oobretlen, ret);
-		if (!ret)
+		if (!ret || mtd_is_bitflip(ret))
 			ret = -EIO;
 		return ret;
 	}
@@ -1086,10 +1086,10 @@  int jffs2_check_nand_cleanmarker(struct jffs2_sb_info *c,
 	ops.datbuf = NULL;
 
 	ret = mtd_read_oob(c->mtd, jeb->offset, &ops);
-	if (ret || ops.oobretlen != ops.ooblen) {
+	if ((ret && !mtd_is_bitflip(ret)) || ops.oobretlen != ops.ooblen) {
 		pr_err("cannot read OOB for EB at %08x, requested %zd bytes, read %zd bytes, error %d\n",
 		       jeb->offset, ops.ooblen, ops.oobretlen, ret);
-		if (!ret)
+		if (!ret || mtd_is_bitflip(ret))
 			ret = -EIO;
 		return ret;
 	}