From cf30a473a02901fe4db37abc0b0fa26dd5ba3f72 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Fri, 6 Jan 2006 00:20:23 -0800 Subject: [PATCH] [PATCH] md: handle errors when read-only Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/raid1.c | 18 +++++++++++------- include/linux/raid/raid1.h | 7 +++++++ 2 files changed, 18 insertions(+), 7 deletions(-) diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 14a8fe0349c..a8bc93d6ff6 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -154,7 +154,7 @@ static void put_all_bios(conf_t *conf, r1bio_t *r1_bio) for (i = 0; i < conf->raid_disks; i++) { struct bio **bio = r1_bio->bios + i; - if (*bio) + if (*bio && *bio != IO_BLOCKED) bio_put(*bio); *bio = NULL; } @@ -419,11 +419,13 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio) new_disk = 0; for (rdev = rcu_dereference(conf->mirrors[new_disk].rdev); + r1_bio->bios[new_disk] == IO_BLOCKED || !rdev || !test_bit(In_sync, &rdev->flags) || test_bit(WriteMostly, &rdev->flags); rdev = rcu_dereference(conf->mirrors[++new_disk].rdev)) { - if (rdev && test_bit(In_sync, &rdev->flags)) + if (rdev && test_bit(In_sync, &rdev->flags) && + r1_bio->bios[new_disk] != IO_BLOCKED) wonly_disk = new_disk; if (new_disk == conf->raid_disks - 1) { @@ -437,11 +439,13 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio) /* make sure the disk is operational */ for (rdev = rcu_dereference(conf->mirrors[new_disk].rdev); + r1_bio->bios[new_disk] == IO_BLOCKED || !rdev || !test_bit(In_sync, &rdev->flags) || test_bit(WriteMostly, &rdev->flags); rdev = rcu_dereference(conf->mirrors[new_disk].rdev)) { - if (rdev && test_bit(In_sync, &rdev->flags)) + if (rdev && test_bit(In_sync, &rdev->flags) && + r1_bio->bios[new_disk] != IO_BLOCKED) wonly_disk = new_disk; if (new_disk <= 0) @@ -478,7 +482,7 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio) rdev = rcu_dereference(conf->mirrors[disk].rdev); - if (!rdev || + if (!rdev || r1_bio->bios[disk] == IO_BLOCKED || !test_bit(In_sync, &rdev->flags) || test_bit(WriteMostly, &rdev->flags)) continue; @@ -1335,7 +1339,7 @@ static void raid1d(mddev_t *mddev) sector_t sect = r1_bio->sector; int sectors = r1_bio->sectors; freeze_array(conf); - while(sectors) { + if (mddev->ro == 0) while(sectors) { int s = sectors; int d = r1_bio->read_disk; int success = 0; @@ -1388,7 +1392,6 @@ static void raid1d(mddev_t *mddev) sect += s; } - unfreeze_array(conf); bio = r1_bio->bios[r1_bio->read_disk]; @@ -1399,7 +1402,8 @@ static void raid1d(mddev_t *mddev) (unsigned long long)r1_bio->sector); raid_end_bio_io(r1_bio); } else { - r1_bio->bios[r1_bio->read_disk] = NULL; + r1_bio->bios[r1_bio->read_disk] = + mddev->ro ? IO_BLOCKED : NULL; r1_bio->read_disk = disk; bio_put(bio); bio = bio_clone(r1_bio->master_bio, GFP_NOIO); diff --git a/include/linux/raid/raid1.h b/include/linux/raid/raid1.h index cbe4238d3f9..9d5494aaac0 100644 --- a/include/linux/raid/raid1.h +++ b/include/linux/raid/raid1.h @@ -109,6 +109,13 @@ struct r1bio_s { /* DO NOT PUT ANY NEW FIELDS HERE - bios array is contiguously alloced*/ }; +/* when we get a read error on a read-only array, we redirect to another + * device without failing the first device, or trying to over-write to + * correct the read error. To keep track of bad blocks on a per-bio + * level, we store IO_BLOCKED in the appropriate 'bios' pointer + */ +#define IO_BLOCKED ((struct bio*)1) + /* bits for r1bio.state */ #define R1BIO_Uptodate 0 #define R1BIO_IsSync 1 -- 2.20.1