linux-kernel - [PATCH] f2fs: use round_up to enhance calculation

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Date:   Wed, 8 Apr 2020 19:55:17 +0800
From:   Chao Yu <yuchao0@...wei.com>
To:     <jaegeuk@...nel.org>
CC:     <linux-f2fs-devel@...ts.sourceforge.net>,
        <linux-kernel@...r.kernel.org>, <chao@...nel.org>,
        Chao Yu <yuchao0@...wei.com>
Subject: [PATCH] f2fs: use round_up to enhance calculation

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

Signed-off-by: Chao Yu <yuchao0@...wei.com>
---
 fs/f2fs/file.c | 17 +++++------------
 1 file changed, 5 insertions(+), 12 deletions(-)

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