[PATCH v2] f2fs: use round_up()/DIV_ROUND_UP()

[Chao Yu]

.i_cluster_size should be power of 2, so we can use round_up() instead
of roundup() to enhance the calculation.

In addition, use DIV_ROUND_UP to clean up codes.

Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
---
v2:
- don't change blocksize to PAGE_SIZE
 fs/f2fs/data.c | 14 ++++++--------
 fs/f2fs/file.c | 17 +++++------------
 2 files changed, 11 insertions(+), 20 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 0a829a89f596..fea93719f14f 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -1969,8 +1969,7 @@ static int f2fs_read_single_page(struct inode *inode, struct page *page,
 					bool is_readahead)
 {
 	struct bio *bio = *bio_ret;
-	const unsigned blkbits = inode->i_blkbits;
-	const unsigned blocksize = 1 << blkbits;
+	const unsigned blocksize = 1 << inode->i_blkbits;
 	sector_t block_in_file;
 	sector_t last_block;
 	sector_t last_block_in_file;
@@ -1979,8 +1978,8 @@ static int f2fs_read_single_page(struct inode *inode, struct page *page,
 
 	block_in_file = (sector_t)page_index(page);
 	last_block = block_in_file + nr_pages;
-	last_block_in_file = (f2fs_readpage_limit(inode) + blocksize - 1) >>
-							blkbits;
+	last_block_in_file = DIV_ROUND_UP(f2fs_readpage_limit(inode),
+								blocksize);
 	if (last_block > last_block_in_file)
 		last_block = last_block_in_file;
 
@@ -2091,16 +2090,15 @@ int f2fs_read_multi_pages(struct compress_ctx *cc, struct bio **bio_ret,
 	struct bio *bio = *bio_ret;
 	unsigned int start_idx = cc->cluster_idx << cc->log_cluster_size;
 	sector_t last_block_in_file;
-	const unsigned blkbits = inode->i_blkbits;
-	const unsigned blocksize = 1 << blkbits;
+	const unsigned blocksize = 1 << inode->i_blkbits;
 	struct decompress_io_ctx *dic = NULL;
 	int i;
 	int ret = 0;
 
 	f2fs_bug_on(sbi, f2fs_cluster_is_empty(cc));
 
-	last_block_in_file = (f2fs_readpage_limit(inode) +
-					blocksize - 1) >> blkbits;
+	last_block_in_file = DIV_ROUND_UP(f2fs_readpage_limit(inode),
+								blocksize);
 
 	/* get rid of pages beyond EOF */
 	for (i = 0; i < cc->cluster_size; i++) {
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index c2d38a1c4972..0f8be076620c 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -736,16 +736,9 @@ int f2fs_truncate_blocks(struct inode *inode, u64 from, bool lock)
 	 * for compressed file, only support cluster size
 	 * aligned truncation.
 	 */
-	if (f2fs_compressed_file(inode)) {
-		size_t cluster_shift = PAGE_SHIFT +
-					F2FS_I(inode)->i_log_cluster_size;
-		size_t cluster_mask = (1 << cluster_shift) - 1;
-
-		free_from = from >> cluster_shift;
-		if (from & cluster_mask)
-			free_from++;
-		free_from <<= cluster_shift;
-	}
+	if (f2fs_compressed_file(inode))
+		free_from = round_up(from,
+				F2FS_I(inode)->i_cluster_size << PAGE_SHIFT);
 #endif
 
 	err = f2fs_do_truncate_blocks(inode, free_from, lock);
@@ -3537,7 +3530,7 @@ static int f2fs_release_compress_blocks(struct file *filp, unsigned long arg)
 
 		end_offset = ADDRS_PER_PAGE(dn.node_page, inode);
 		count = min(end_offset - dn.ofs_in_node, last_idx - page_idx);
-		count = roundup(count, F2FS_I(inode)->i_cluster_size);
+		count = round_up(count, F2FS_I(inode)->i_cluster_size);
 
 		ret = release_compress_blocks(&dn, count);
 
@@ -3689,7 +3682,7 @@ static int f2fs_reserve_compress_blocks(struct file *filp, unsigned long arg)
 
 		end_offset = ADDRS_PER_PAGE(dn.node_page, inode);
 		count = min(end_offset - dn.ofs_in_node, last_idx - page_idx);
-		count = roundup(count, F2FS_I(inode)->i_cluster_size);
+		count = round_up(count, F2FS_I(inode)->i_cluster_size);
 
 		ret = reserve_compress_blocks(&dn, count);
 
-- 
2.18.0.rc1