From: NeilBrown <neilb@suse.de>
To: Andrew Morton <akpm@osdl.org>
Cc: linux-raid@vger.kernel.org
Subject: [PATCH md 014 of 14] Fix possible problem in raid1/raid10 error overwriting.
Date: Thu, 1 Dec 2005 14:24:02 +1100 [thread overview]
Message-ID: <1051201032402.29735@suse.de> (raw)
In-Reply-To: 20051201141508.29384.patches@notabene
The code to overwrite/reread for addressing read errors
in raid1/raid10 currently assumes that the read will
not alter the buffer which could be used to write to
the next device. This is not a safe assumption to make.
So we split the loops into a overwrite loop and a separate re-read
loop, so that the writing is complete before reading is attempted.
Cc: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Neil Brown <neilb@suse.de>
### Diffstat output
./drivers/md/raid1.c | 38 ++++++++++++++++++++++++++++++--------
./drivers/md/raid10.c | 22 ++++++++++++++++++----
2 files changed, 48 insertions(+), 12 deletions(-)
diff ./drivers/md/raid1.c~current~ ./drivers/md/raid1.c
--- ./drivers/md/raid1.c~current~ 2005-12-01 14:03:25.000000000 +1100
+++ ./drivers/md/raid1.c 2005-12-01 14:03:40.000000000 +1100
@@ -1252,6 +1252,7 @@ static void sync_request_write(mddev_t *
} while (!success && d != r1_bio->read_disk);
if (success) {
+ int start = d;
/* write it back and re-read */
set_bit(R1BIO_Uptodate, &r1_bio->state);
while (d != r1_bio->read_disk) {
@@ -1265,14 +1266,23 @@ static void sync_request_write(mddev_t *
sect + rdev->data_offset,
s<<9,
bio->bi_io_vec[idx].bv_page,
- WRITE) == 0 ||
- sync_page_io(rdev->bdev,
+ WRITE) == 0)
+ md_error(mddev, rdev);
+ }
+ d = start;
+ while (d != r1_bio->read_disk) {
+ if (d == 0)
+ d = conf->raid_disks;
+ d--;
+ if (r1_bio->bios[d]->bi_end_io != end_sync_read)
+ continue;
+ rdev = conf->mirrors[d].rdev;
+ if (sync_page_io(rdev->bdev,
sect + rdev->data_offset,
s<<9,
bio->bi_io_vec[idx].bv_page,
- READ) == 0) {
+ READ) == 0)
md_error(mddev, rdev);
- }
}
} else {
char b[BDEVNAME_SIZE];
@@ -1444,6 +1454,7 @@ static void raid1d(mddev_t *mddev)
if (success) {
/* write it back and re-read */
+ int start = d;
while (d != r1_bio->read_disk) {
if (d==0)
d = conf->raid_disks;
@@ -1453,13 +1464,24 @@ static void raid1d(mddev_t *mddev)
test_bit(In_sync, &rdev->flags)) {
if (sync_page_io(rdev->bdev,
sect + rdev->data_offset,
- s<<9, conf->tmppage, WRITE) == 0 ||
- sync_page_io(rdev->bdev,
+ s<<9, conf->tmppage, WRITE) == 0)
+ /* Well, this device is dead */
+ md_error(mddev, rdev);
+ }
+ }
+ d = start;
+ while (d != r1_bio->read_disk) {
+ if (d==0)
+ d = conf->raid_disks;
+ d--;
+ rdev = conf->mirrors[d].rdev;
+ if (rdev &&
+ test_bit(In_sync, &rdev->flags)) {
+ if (sync_page_io(rdev->bdev,
sect + rdev->data_offset,
- s<<9, conf->tmppage, READ) == 0) {
+ s<<9, conf->tmppage, READ) == 0)
/* Well, this device is dead */
md_error(mddev, rdev);
- }
}
}
} else {
diff ./drivers/md/raid10.c~current~ ./drivers/md/raid10.c
--- ./drivers/md/raid10.c~current~ 2005-12-01 14:03:25.000000000 +1100
+++ ./drivers/md/raid10.c 2005-12-01 14:03:41.000000000 +1100
@@ -1421,6 +1421,7 @@ static void raid10d(mddev_t *mddev)
} while (!success && sl != r10_bio->read_slot);
if (success) {
+ int start = sl;
/* write it back and re-read */
while (sl != r10_bio->read_slot) {
int d;
@@ -1434,14 +1435,27 @@ static void raid10d(mddev_t *mddev)
if (sync_page_io(rdev->bdev,
r10_bio->devs[sl].addr +
sect + rdev->data_offset,
- s<<9, conf->tmppage, WRITE) == 0 ||
- sync_page_io(rdev->bdev,
+ s<<9, conf->tmppage, WRITE) == 0)
+ /* Well, this device is dead */
+ md_error(mddev, rdev);
+ }
+ }
+ sl = start;
+ while (sl != r10_bio->read_slot) {
+ int d;
+ if (sl==0)
+ sl = conf->copies;
+ sl--;
+ d = r10_bio->devs[sl].devnum;
+ rdev = conf->mirrors[d].rdev;
+ if (rdev &&
+ test_bit(In_sync, &rdev->flags)) {
+ if (sync_page_io(rdev->bdev,
r10_bio->devs[sl].addr +
sect + rdev->data_offset,
- s<<9, conf->tmppage, READ) == 0) {
+ s<<9, conf->tmppage, READ) == 0)
/* Well, this device is dead */
md_error(mddev, rdev);
- }
}
}
} else {
prev parent reply other threads:[~2005-12-01 3:24 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-12-01 3:22 [PATCH md 000 of 14] Introduction NeilBrown
2005-12-01 3:22 ` [PATCH md 001 of 14] Support check-without-repair of raid10 arrays NeilBrown
2005-12-01 3:22 ` [PATCH md 002 of 14] Allow raid1 to check consistency NeilBrown
2005-12-01 22:34 ` Andrew Morton
2005-12-05 23:30 ` Neil Brown
2005-12-06 3:50 ` Andrew Morton
2005-12-01 3:23 ` [PATCH md 003 of 14] Make sure read error on last working drive of raid1 actually returns failure NeilBrown
2005-12-01 3:23 ` [PATCH md 004 of 14] auto-correct correctable read errors in raid10 NeilBrown
2005-12-01 3:23 ` [PATCH md 005 of 14] raid10 read-error handling - resync and read-only NeilBrown
2005-12-01 3:23 ` [PATCH md 006 of 14] Make /proc/mdstat pollable NeilBrown
2005-12-01 22:39 ` Andrew Morton
2005-12-01 3:23 ` [PATCH md 007 of 14] Clean up 'page' related names in md NeilBrown
2005-12-01 3:23 ` [PATCH md 008 of 14] Convert md to use kzalloc throughout NeilBrown
2005-12-01 22:42 ` Andrew Morton
2005-12-01 3:23 ` [PATCH md 009 of 14] Tidy up raid5/6 hash table code NeilBrown
2005-12-01 3:23 ` [PATCH md 010 of 14] Convert various kmap calls to kmap_atomic NeilBrown
2005-12-01 22:46 ` Andrew Morton
2005-12-05 23:43 ` Neil Brown
2005-12-01 3:23 ` [PATCH md 011 of 14] Convert recently exported symbol to GPL NeilBrown
2005-12-01 3:23 ` [PATCH md 012 of 14] Break out of a loop that doesn't need to run to completion NeilBrown
2005-12-01 3:23 ` [PATCH md 013 of 14] Remove personality numbering from md NeilBrown
2005-12-01 3:24 ` NeilBrown [this message]
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