btrfs: use DIV_ROUND_UP instead of open-coded variants
The form
(value + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT
is equivalent to
(value + PAGE_CACHE_SIZE - 1) / PAGE_CACHE_SIZE
The rest is a simple subsitution, no difference in the generated
assembly code.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
diff --git a/fs/btrfs/zlib.c b/fs/btrfs/zlib.c
index b67d8fc..77a0e5d 100644
--- a/fs/btrfs/zlib.c
+++ b/fs/btrfs/zlib.c
@@ -225,8 +225,7 @@
size_t total_out = 0;
unsigned long page_in_index = 0;
unsigned long page_out_index = 0;
- unsigned long total_pages_in = (srclen + PAGE_CACHE_SIZE - 1) /
- PAGE_CACHE_SIZE;
+ unsigned long total_pages_in = DIV_ROUND_UP(srclen, PAGE_CACHE_SIZE);
unsigned long buf_start;
unsigned long pg_offset;