[PATCH 01/12] btrfs: add helpers for compression type and level

[Dennis Zhou]

It is very easy to miss places that rely on a certain bitshifting for
decyphering the type_level overloading. Add helpers to do this instead.

Signed-off-by: Dennis Zhou <den...@kernel.org>
Reviewed-by: Nikolay Borisov <nbori...@suse.com>
Reviewed-by: Josef Bacik <jo...@toxicpanda.com>
Cc: Omar Sandoval <osan...@osandov.com>
---
 fs/btrfs/compression.c |  2 +-
 fs/btrfs/compression.h | 10 ++++++++++
 fs/btrfs/zlib.c        |  2 +-
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 548057630b69..94a0b0a3a301 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -1036,9 +1036,9 @@ int btrfs_compress_pages(unsigned int type_level, struct 
address_space *mapping,
                         unsigned long *total_in,
                         unsigned long *total_out)
 {
+       int type = btrfs_compress_type(type_level);
        struct list_head *workspace;
        int ret;
-       int type = type_level & 0xF;
 
        workspace = find_workspace(type);
 
diff --git a/fs/btrfs/compression.h b/fs/btrfs/compression.h
index ddda9b80bf20..004db0b3111b 100644
--- a/fs/btrfs/compression.h
+++ b/fs/btrfs/compression.h
@@ -64,6 +64,16 @@ struct compressed_bio {
        u32 sums;
 };
 
+static inline unsigned int btrfs_compress_type(unsigned int type_level)
+{
+       return (type_level & 0xF);
+}
+
+static inline unsigned int btrfs_compress_level(unsigned int type_level)
+{
+       return ((type_level & 0xF0) >> 4);
+}
+
 void __init btrfs_init_compress(void);
 void __cold btrfs_exit_compress(void);
 
diff --git a/fs/btrfs/zlib.c b/fs/btrfs/zlib.c
index 970ff3e35bb3..2bd655c4f8b4 100644
--- a/fs/btrfs/zlib.c
+++ b/fs/btrfs/zlib.c
@@ -393,7 +393,7 @@ static int zlib_decompress(struct list_head *ws, unsigned 
char *data_in,
 static void zlib_set_level(struct list_head *ws, unsigned int type)
 {
        struct workspace *workspace = list_entry(ws, struct workspace, list);
-       unsigned level = (type & 0xF0) >> 4;
+       unsigned int level = btrfs_compress_level(type);
 
        if (level > 9)
                level = 9;
-- 
2.17.1