btrfs: fix structs where bitfields and spinlock/atomic share 8B word

On ia64, powerpc64 and sparc64 the bitfield is modified through a RMW cycle and current gcc rewrites the adjacent 4B word, which in case of a spinlock or atomic has disaterous effect. https://lkml.org/lkml/2012/2/1/220 Signed-off-by: David Sterba <dsterba@suse.cz>
mariux64 · Feb 15, 2012 · c08782d · c08782d
1 parent 87826df
commit c08782d
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Showing 2 changed files with 3 additions and 3 deletions.
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
@@ -886,7 +886,7 @@ struct btrfs_block_rsv {
 	u64 reserved;
 	struct btrfs_space_info *space_info;
 	spinlock_t lock;
-	unsigned int full:1;
+	unsigned int full;
 };
 
 /*

diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
@@ -26,8 +26,8 @@ struct extent_map {
 	unsigned long flags;
 	struct block_device *bdev;
 	atomic_t refs;
-	unsigned int in_tree:1;
-	unsigned int compress_type:4;
+	unsigned int in_tree;
+	unsigned int compress_type;
 };
 
 struct extent_map_tree {