btrfs: cleanup, stop casting for extent_map->lookup everywhere
Overloading extent_map->bdev to struct map_lookup * might have started out
as a means to an end, but it's a pattern that's used all over the place
now. Let's get rid of the casting and just add a union instead.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index 1e668fb..cbb7dbf 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -614,7 +614,7 @@
em = lookup_extent_mapping(em_tree, start, (u64)-1);
if (!em)
break;
- map = (struct map_lookup *)em->bdev;
+ map = em->map_lookup;
for (i = 0; i < map->num_stripes; i++)
if (srcdev == map->stripes[i].dev)
map->stripes[i].dev = tgtdev;
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 1ea56d8..8c91289 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -10322,7 +10322,7 @@
* more device items and remove one chunk item), but this is done at
* btrfs_remove_chunk() through a call to check_system_chunk().
*/
- map = (struct map_lookup *)em->bdev;
+ map = em->map_lookup;
num_items = 3 + map->num_stripes;
free_extent_map(em);
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 6a98bdd..84fb56d 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -76,7 +76,7 @@
WARN_ON(extent_map_in_tree(em));
WARN_ON(!list_empty(&em->list));
if (test_bit(EXTENT_FLAG_FS_MAPPING, &em->flags))
- kfree(em->bdev);
+ kfree(em->map_lookup);
kmem_cache_free(extent_map_cache, em);
}
}
diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index b2991fd..eb8b8fa 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -32,7 +32,15 @@
u64 block_len;
u64 generation;
unsigned long flags;
- struct block_device *bdev;
+ union {
+ struct block_device *bdev;
+
+ /*
+ * used for chunk mappings
+ * flags & EXTENT_FLAG_FS_MAPPING must be set
+ */
+ struct map_lookup *map_lookup;
+ };
atomic_t refs;
unsigned int compress_type;
struct list_head list;
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index b57a15a..151000f 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -3458,7 +3458,7 @@
return ret;
}
- map = (struct map_lookup *)em->bdev;
+ map = em->map_lookup;
if (em->start != chunk_offset)
goto out;
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index adb79ad..9cb78e3 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1182,7 +1182,7 @@
struct map_lookup *map;
int i;
- map = (struct map_lookup *)em->bdev;
+ map = em->map_lookup;
for (i = 0; i < map->num_stripes; i++) {
u64 end;
@@ -2754,7 +2754,7 @@
free_extent_map(em);
return -EINVAL;
}
- map = (struct map_lookup *)em->bdev;
+ map = em->map_lookup;
lock_chunks(root->fs_info->chunk_root);
check_system_chunk(trans, extent_root, map->type);
unlock_chunks(root->fs_info->chunk_root);
@@ -4718,7 +4718,7 @@
goto error;
}
set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
- em->bdev = (struct block_device *)map;
+ em->map_lookup = map;
em->start = start;
em->len = num_bytes;
em->block_start = 0;
@@ -4813,7 +4813,7 @@
return -EINVAL;
}
- map = (struct map_lookup *)em->bdev;
+ map = em->map_lookup;
item_size = btrfs_chunk_item_size(map->num_stripes);
stripe_size = em->orig_block_len;
@@ -4955,7 +4955,7 @@
if (!em)
return 1;
- map = (struct map_lookup *)em->bdev;
+ map = em->map_lookup;
for (i = 0; i < map->num_stripes; i++) {
if (map->stripes[i].dev->missing) {
miss_ndevs++;
@@ -5035,7 +5035,7 @@
return 1;
}
- map = (struct map_lookup *)em->bdev;
+ map = em->map_lookup;
if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
ret = map->num_stripes;
else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
@@ -5071,7 +5071,7 @@
BUG_ON(!em);
BUG_ON(em->start > logical || em->start + em->len < logical);
- map = (struct map_lookup *)em->bdev;
+ map = em->map_lookup;
if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
len = map->stripe_len * nr_data_stripes(map);
free_extent_map(em);
@@ -5092,7 +5092,7 @@
BUG_ON(!em);
BUG_ON(em->start > logical || em->start + em->len < logical);
- map = (struct map_lookup *)em->bdev;
+ map = em->map_lookup;
if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
ret = 1;
free_extent_map(em);
@@ -5251,7 +5251,7 @@
return -EINVAL;
}
- map = (struct map_lookup *)em->bdev;
+ map = em->map_lookup;
offset = logical - em->start;
stripe_len = map->stripe_len;
@@ -5793,7 +5793,7 @@
free_extent_map(em);
return -EIO;
}
- map = (struct map_lookup *)em->bdev;
+ map = em->map_lookup;
length = em->len;
rmap_len = map->stripe_len;
@@ -6229,7 +6229,7 @@
}
set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
- em->bdev = (struct block_device *)map;
+ em->map_lookup = map;
em->start = logical;
em->len = length;
em->orig_start = 0;
@@ -6920,7 +6920,7 @@
/* In order to kick the device replace finish process */
lock_chunks(root);
list_for_each_entry(em, &transaction->pending_chunks, list) {
- map = (struct map_lookup *)em->bdev;
+ map = em->map_lookup;
for (i = 0; i < map->num_stripes; i++) {
dev = map->stripes[i].dev;