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>
diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index 33a7890..1195f09 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -26,8 +26,8 @@
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 {