The part of btrfs_map_block() that decodes the extent map and rw/logical/length/mirror parameters is split into a routine btrfs_map_to_stripe() so direct I/O can build multiple bios with one lookup_extent_mapping().
The part of btrfs_map_block() that does lookup_extent_mapping() and optional creation of the btrfs_multi_bio struct now calls btrfs_map_to_stripe(). Signed-off-by: jim owens <[email protected]> Signed-off-by: jim owens <[email protected]> --- V2 fixes long line checkpatch warning fs/btrfs/volumes.c | 85 +++++++++++++++++++++++++++++++-------------------- fs/btrfs/volumes.h | 10 ++++++ 2 files changed, 62 insertions(+), 33 deletions(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 98c0924..ee66267 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -2619,33 +2619,16 @@ static int find_live_mirror(struct map_lookup *map, int first, int num, return optimal; } -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) +void btrfs_map_to_stripe(struct extent_map *em, int rw, int mirror_num, + u64 logical, u64 *length, + struct btrfs_stripe_info *stripe_info) { - struct extent_map *em; struct map_lookup *map; - struct extent_map_tree *em_tree = &map_tree->map_tree; u64 offset; u64 stripe_offset; u64 stripe_nr; int stripe_index; - int i; int num_stripes; - int max_errors; - struct btrfs_multi_bio *multi; - - read_lock(&em_tree->lock); - em = lookup_extent_mapping(em_tree, logical, *length); - read_unlock(&em_tree->lock); - - if (!em) { - printk(KERN_CRIT "unable to find logical %llu len %llu\n", - (unsigned long long)logical, - (unsigned long long)*length); - BUG(); - } BUG_ON(em->start > logical || em->start + em->len < logical); map = (struct map_lookup *)em->bdev; @@ -2675,19 +2658,19 @@ int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, *length = min(*length, em->len - offset); } - if (!multi_ret) - goto out; + if (!stripe_info) + return; if (mirror_num > map->num_stripes) mirror_num = 0; - max_errors = 0; + stripe_info->max_errors = 0; if (rw & (1 << BIO_RW)) { if (map->type & (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_DUP)) - max_errors = 1; + stripe_info->max_errors = 1; else if (map->type & BTRFS_BLOCK_GROUP_RAID10) - max_errors = 1; + stripe_info->max_errors = 1; } num_stripes = 1; @@ -2734,22 +2717,58 @@ int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, } BUG_ON(stripe_index >= map->num_stripes); - multi = kzalloc(btrfs_multi_bio_size(num_stripes), GFP_NOFS); + stripe_info->num_stripes = num_stripes; + stripe_info->stripe_index = stripe_index; + stripe_info->phys_offset = stripe_offset + stripe_nr * map->stripe_len; +} + +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 extent_map *em; + struct map_lookup *map; + struct extent_map_tree *em_tree = &map_tree->map_tree; + struct btrfs_multi_bio *multi; + struct btrfs_stripe_info stripe_info; + int i; + + read_lock(&em_tree->lock); + em = lookup_extent_mapping(em_tree, logical, *length); + read_unlock(&em_tree->lock); + + if (!em) { + printk(KERN_CRIT "unable to find logical %llu len %llu\n", + (unsigned long long)logical, + (unsigned long long)*length); + BUG(); + } + + btrfs_map_to_stripe(em, rw, mirror_num, logical, length, + multi_ret ? &stripe_info : NULL); + if (!multi_ret) + goto out; + + multi = kzalloc(btrfs_multi_bio_size(stripe_info.num_stripes), + GFP_NOFS); if (!multi) return -ENOMEM; *multi_ret = multi; atomic_set(&multi->error, 0); - multi->num_stripes = num_stripes; - multi->max_errors = max_errors; + multi->num_stripes = stripe_info.num_stripes; + multi->max_errors = stripe_info.max_errors; - for (i = 0; i < num_stripes; i++) { + map = (struct map_lookup *)em->bdev; + for (i = 0; i < stripe_info.num_stripes; i++) { multi->stripes[i].physical = - map->stripes[stripe_index].physical + - stripe_offset + stripe_nr * map->stripe_len; - multi->stripes[i].dev = map->stripes[stripe_index].dev; - stripe_index++; + map->stripes[stripe_info.stripe_index].physical + + stripe_info.phys_offset; + multi->stripes[i].dev = + map->stripes[stripe_info.stripe_index].dev; + stripe_info.stripe_index++; } + out: free_extent_map(em); return 0; diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index d5aab74..76c4394 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h @@ -135,6 +135,13 @@ struct btrfs_multi_bio { struct btrfs_bio_stripe stripes[]; }; +struct btrfs_stripe_info { + int num_stripes; + int max_errors; + int stripe_index; + u64 phys_offset; +}; + #define btrfs_multi_bio_size(n) (sizeof(struct btrfs_multi_bio) + \ (sizeof(struct btrfs_bio_stripe) * (n))) @@ -142,6 +149,9 @@ int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans, struct btrfs_device *device, u64 chunk_tree, u64 chunk_objectid, u64 chunk_offset, u64 start, u64 num_bytes); +void btrfs_map_to_stripe(struct extent_map *em, int rw, int mirror_num, + u64 logical, u64 *length, + struct btrfs_stripe_info *stripe_info); 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); -- 1.6.3.3 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
