From a1d3c4786a4b9c71c0767aa656a759968f7554b6 Mon Sep 17 00:00:00 2001 From: Jan Schmidt Date: Thu, 4 Aug 2011 17:15:33 +0200 Subject: btrfs: btrfs_multi_bio replaced with btrfs_bio btrfs_bio is a bio abstraction able to split and not complete after the last bio has returned (like the old btrfs_multi_bio). Additionally, btrfs_bio tracks the mirror_num used to read data which can be used for error correction purposes. Signed-off-by: Jan Schmidt --- fs/btrfs/volumes.c | 128 ++++++++++++++++++++++++++++------------------------- 1 file changed, 68 insertions(+), 60 deletions(-) (limited to 'fs/btrfs/volumes.c') diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index f2a4cc79da61..9db4d7962f9b 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -2848,7 +2848,7 @@ static int find_live_mirror(struct map_lookup *map, int first, int num, static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, u64 logical, u64 *length, - struct btrfs_multi_bio **multi_ret, + struct btrfs_bio **bbio_ret, int mirror_num) { struct extent_map *em; @@ -2866,18 +2866,18 @@ static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, int i; int num_stripes; int max_errors = 0; - struct btrfs_multi_bio *multi = NULL; + struct btrfs_bio *bbio = NULL; - if (multi_ret && !(rw & (REQ_WRITE | REQ_DISCARD))) + if (bbio_ret && !(rw & (REQ_WRITE | REQ_DISCARD))) stripes_allocated = 1; again: - if (multi_ret) { - multi = kzalloc(btrfs_multi_bio_size(stripes_allocated), + if (bbio_ret) { + bbio = kzalloc(btrfs_bio_size(stripes_allocated), GFP_NOFS); - if (!multi) + if (!bbio) return -ENOMEM; - atomic_set(&multi->error, 0); + atomic_set(&bbio->error, 0); } read_lock(&em_tree->lock); @@ -2898,7 +2898,7 @@ again: if (mirror_num > map->num_stripes) mirror_num = 0; - /* if our multi bio struct is too small, back off and try again */ + /* if our btrfs_bio struct is too small, back off and try again */ if (rw & REQ_WRITE) { if (map->type & (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_DUP)) { @@ -2917,11 +2917,11 @@ again: stripes_required = map->num_stripes; } } - if (multi_ret && (rw & (REQ_WRITE | REQ_DISCARD)) && + if (bbio_ret && (rw & (REQ_WRITE | REQ_DISCARD)) && stripes_allocated < stripes_required) { stripes_allocated = map->num_stripes; free_extent_map(em); - kfree(multi); + kfree(bbio); goto again; } stripe_nr = offset; @@ -2950,7 +2950,7 @@ again: *length = em->len - offset; } - if (!multi_ret) + if (!bbio_ret) goto out; num_stripes = 1; @@ -2975,13 +2975,17 @@ again: stripe_index = find_live_mirror(map, 0, map->num_stripes, current->pid % map->num_stripes); + mirror_num = stripe_index + 1; } } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { - if (rw & (REQ_WRITE | REQ_DISCARD)) + if (rw & (REQ_WRITE | REQ_DISCARD)) { num_stripes = map->num_stripes; - else if (mirror_num) + } else if (mirror_num) { stripe_index = mirror_num - 1; + } else { + mirror_num = 1; + } } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { int factor = map->num_stripes / map->sub_stripes; @@ -3001,6 +3005,7 @@ again: stripe_index = find_live_mirror(map, stripe_index, map->sub_stripes, stripe_index + current->pid % map->sub_stripes); + mirror_num = stripe_index + 1; } } else { /* @@ -3009,15 +3014,16 @@ again: * stripe_index is the number of our device in the stripe array */ stripe_index = do_div(stripe_nr, map->num_stripes); + mirror_num = stripe_index + 1; } BUG_ON(stripe_index >= map->num_stripes); if (rw & REQ_DISCARD) { for (i = 0; i < num_stripes; i++) { - multi->stripes[i].physical = + bbio->stripes[i].physical = map->stripes[stripe_index].physical + stripe_offset + stripe_nr * map->stripe_len; - multi->stripes[i].dev = map->stripes[stripe_index].dev; + bbio->stripes[i].dev = map->stripes[stripe_index].dev; if (map->type & BTRFS_BLOCK_GROUP_RAID0) { u64 stripes; @@ -3038,16 +3044,16 @@ again: } stripes = stripe_nr_end - 1 - j; do_div(stripes, map->num_stripes); - multi->stripes[i].length = map->stripe_len * + bbio->stripes[i].length = map->stripe_len * (stripes - stripe_nr + 1); if (i == 0) { - multi->stripes[i].length -= + bbio->stripes[i].length -= stripe_offset; stripe_offset = 0; } if (stripe_index == last_stripe) - multi->stripes[i].length -= + bbio->stripes[i].length -= stripe_end_offset; } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { u64 stripes; @@ -3072,11 +3078,11 @@ again: } stripes = stripe_nr_end - 1 - j; do_div(stripes, factor); - multi->stripes[i].length = map->stripe_len * + bbio->stripes[i].length = map->stripe_len * (stripes - stripe_nr + 1); if (i < map->sub_stripes) { - multi->stripes[i].length -= + bbio->stripes[i].length -= stripe_offset; if (i == map->sub_stripes - 1) stripe_offset = 0; @@ -3084,11 +3090,11 @@ again: if (stripe_index >= last_stripe && stripe_index <= (last_stripe + map->sub_stripes - 1)) { - multi->stripes[i].length -= + bbio->stripes[i].length -= stripe_end_offset; } } else - multi->stripes[i].length = *length; + bbio->stripes[i].length = *length; stripe_index++; if (stripe_index == map->num_stripes) { @@ -3099,19 +3105,20 @@ again: } } else { for (i = 0; i < num_stripes; i++) { - multi->stripes[i].physical = + bbio->stripes[i].physical = map->stripes[stripe_index].physical + stripe_offset + stripe_nr * map->stripe_len; - multi->stripes[i].dev = + bbio->stripes[i].dev = map->stripes[stripe_index].dev; stripe_index++; } } - if (multi_ret) { - *multi_ret = multi; - multi->num_stripes = num_stripes; - multi->max_errors = max_errors; + if (bbio_ret) { + *bbio_ret = bbio; + bbio->num_stripes = num_stripes; + bbio->max_errors = max_errors; + bbio->mirror_num = mirror_num; } out: free_extent_map(em); @@ -3120,9 +3127,9 @@ out: int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, u64 logical, u64 *length, - struct btrfs_multi_bio **multi_ret, int mirror_num) + struct btrfs_bio **bbio_ret, int mirror_num) { - return __btrfs_map_block(map_tree, rw, logical, length, multi_ret, + return __btrfs_map_block(map_tree, rw, logical, length, bbio_ret, mirror_num); } @@ -3191,28 +3198,28 @@ int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree, return 0; } -static void end_bio_multi_stripe(struct bio *bio, int err) +static void btrfs_end_bio(struct bio *bio, int err) { - struct btrfs_multi_bio *multi = bio->bi_private; + struct btrfs_bio *bbio = bio->bi_private; int is_orig_bio = 0; if (err) - atomic_inc(&multi->error); + atomic_inc(&bbio->error); - if (bio == multi->orig_bio) + if (bio == bbio->orig_bio) is_orig_bio = 1; - if (atomic_dec_and_test(&multi->stripes_pending)) { + if (atomic_dec_and_test(&bbio->stripes_pending)) { if (!is_orig_bio) { bio_put(bio); - bio = multi->orig_bio; + bio = bbio->orig_bio; } - bio->bi_private = multi->private; - bio->bi_end_io = multi->end_io; + bio->bi_private = bbio->private; + bio->bi_end_io = bbio->end_io; /* only send an error to the higher layers if it is * beyond the tolerance of the multi-bio */ - if (atomic_read(&multi->error) > multi->max_errors) { + if (atomic_read(&bbio->error) > bbio->max_errors) { err = -EIO; } else if (err) { /* @@ -3222,7 +3229,7 @@ static void end_bio_multi_stripe(struct bio *bio, int err) set_bit(BIO_UPTODATE, &bio->bi_flags); err = 0; } - kfree(multi); + kfree(bbio); bio_endio(bio, err); } else if (!is_orig_bio) { @@ -3302,20 +3309,20 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, u64 logical = (u64)bio->bi_sector << 9; u64 length = 0; u64 map_length; - struct btrfs_multi_bio *multi = NULL; int ret; int dev_nr = 0; int total_devs = 1; + struct btrfs_bio *bbio = NULL; length = bio->bi_size; map_tree = &root->fs_info->mapping_tree; map_length = length; - ret = btrfs_map_block(map_tree, rw, logical, &map_length, &multi, + ret = btrfs_map_block(map_tree, rw, logical, &map_length, &bbio, mirror_num); BUG_ON(ret); - total_devs = multi->num_stripes; + total_devs = bbio->num_stripes; if (map_length < length) { printk(KERN_CRIT "mapping failed logical %llu bio len %llu " "len %llu\n", (unsigned long long)logical, @@ -3323,25 +3330,28 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, (unsigned long long)map_length); BUG(); } - multi->end_io = first_bio->bi_end_io; - multi->private = first_bio->bi_private; - multi->orig_bio = first_bio; - atomic_set(&multi->stripes_pending, multi->num_stripes); + + bbio->orig_bio = first_bio; + bbio->private = first_bio->bi_private; + bbio->end_io = first_bio->bi_end_io; + atomic_set(&bbio->stripes_pending, bbio->num_stripes); while (dev_nr < total_devs) { - if (total_devs > 1) { - if (dev_nr < total_devs - 1) { - bio = bio_clone(first_bio, GFP_NOFS); - BUG_ON(!bio); - } else { - bio = first_bio; - } - bio->bi_private = multi; - bio->bi_end_io = end_bio_multi_stripe; + if (dev_nr < total_devs - 1) { + bio = bio_clone(first_bio, GFP_NOFS); + BUG_ON(!bio); + } else { + bio = first_bio; } - bio->bi_sector = multi->stripes[dev_nr].physical >> 9; - dev = multi->stripes[dev_nr].dev; + bio->bi_private = bbio; + bio->bi_end_io = btrfs_end_bio; + bio->bi_sector = bbio->stripes[dev_nr].physical >> 9; + dev = bbio->stripes[dev_nr].dev; if (dev && dev->bdev && (rw != WRITE || dev->writeable)) { + pr_debug("btrfs_map_bio: rw %d, secor=%llu, dev=%lu " + "(%s id %llu), size=%u\n", rw, + (u64)bio->bi_sector, (u_long)dev->bdev->bd_dev, + dev->name, dev->devid, bio->bi_size); bio->bi_bdev = dev->bdev; if (async_submit) schedule_bio(root, dev, rw, bio); @@ -3354,8 +3364,6 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, } dev_nr++; } - if (total_devs == 1) - kfree(multi); return 0; } -- cgit v1.2.3-55-g7522 From 2774b2ca3d49124bf1ae89e8d575b3dab4221266 Mon Sep 17 00:00:00 2001 From: Jan Schmidt Date: Thu, 16 Jun 2011 12:05:19 +0200 Subject: btrfs: Put mirror_num in bi_bdev The error correction code wants to make sure that only the bad mirror is rewritten. Thus, we need to know which mirror is the bad one. I did not find a more apropriate field than bi_bdev. But I think using this is fine, because it is modified by the block layer, anyway, and should not be read after the bio returned. Signed-off-by: Jan Schmidt --- fs/btrfs/volumes.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/btrfs/volumes.c') diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 9db4d7962f9b..18baac5a3f6c 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -3216,6 +3216,8 @@ static void btrfs_end_bio(struct bio *bio, int err) } bio->bi_private = bbio->private; bio->bi_end_io = bbio->end_io; + bio->bi_bdev = (struct block_device *) + (unsigned long)bbio->mirror_num; /* only send an error to the higher layers if it is * beyond the tolerance of the multi-bio */ -- cgit v1.2.3-55-g7522