jim owens
2010-Mar-22 03:29 UTC
[PATCH V3 12/18] Btrfs: add direct I/O helper to return mirror count from extent_map.
Direct I/O retry needs to know the number of mirror copies.
Signed-off-by: jim owens <owens6336@gmail.com>
---
fs/btrfs/volumes.c | 22 ++++++++++++++--------
fs/btrfs/volumes.h | 1 +
2 files changed, 15 insertions(+), 8 deletions(-)
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 5a44c5c..aedef39 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -2586,10 +2586,20 @@ void btrfs_mapping_tree_free(struct btrfs_mapping_tree
*tree)
}
}
+int btrfs_map_num_copies(struct extent_map *em)
+{
+ struct map_lookup *map = (struct map_lookup *)em->bdev;
+
+ if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
+ return map->num_stripes;
+ if (map->type & BTRFS_BLOCK_GROUP_RAID10)
+ return map->sub_stripes;
+ return 1;
+}
+
int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len)
{
struct extent_map *em;
- struct map_lookup *map;
struct extent_map_tree *em_tree = &map_tree->map_tree;
int ret;
@@ -2599,13 +2609,9 @@ int btrfs_num_copies(struct btrfs_mapping_tree *map_tree,
u64 logical, u64 len)
BUG_ON(!em);
BUG_ON(em->start > logical || em->start + em->len < logical);
- map = (struct map_lookup *)em->bdev;
- if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
- ret = map->num_stripes;
- else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
- ret = map->sub_stripes;
- else
- ret = 1;
+
+ ret = btrfs_map_num_copies(em);
+
free_extent_map(em);
return ret;
}
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 226200d..732c8c5 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -195,4 +195,5 @@ int find_free_dev_extent(struct btrfs_trans_handle *trans,
int btrfs_map_stripe_count(struct extent_map *em);
struct block_device *btrfs_map_stripe_bdev(struct extent_map *em, int stripe);
u64 btrfs_map_stripe_physical(struct extent_map *em, int stripe);
+int btrfs_map_num_copies(struct extent_map *em);
#endif
--
1.6.3.3
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