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@xxxxxxxxxxxx> Signed-off-by: Neil Brown <neilb@xxxxxxx> ### 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 { - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html