linux-kernel - [PATCH 1/3] f2fs: clean up check condition for writting beyond EOF

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Date:   Fri, 1 Nov 2019 17:53:22 +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 1/3] f2fs: clean up check condition for writting beyond EOF

Clean up with below codes suggested by Eric:

__write_data_page()

	unsigned nr_pages = DIV_ROUND_UP(i_size, PAGE_SIZE);

	/*
	 * If the offset is out-of-range of file size,
	 * this page does not have to be written to disk.
	 */
	if (page->index >= nr_pages)
		goto out;

Signed-off-by: Chao Yu <yuchao0@...wei.com>
---
 fs/f2fs/data.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index ba3bcf4c7889..ca7161e38d1f 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -2204,6 +2204,7 @@ static int __write_data_page(struct page *page, bool *submitted,
 	const pgoff_t end_index = ((unsigned long long) i_size)
 							>> PAGE_SHIFT;
 	loff_t psize = (page->index + 1) << PAGE_SHIFT;
+	unsigned nr_pages = DIV_ROUND_UP(i_size, PAGE_SIZE);
 	unsigned offset = 0;
 	bool need_balance_fs = false;
 	int err = 0;
@@ -2248,8 +2249,7 @@ static int __write_data_page(struct page *page, bool *submitted,
 	 * If the offset is out-of-range of file size,
 	 * this page does not have to be written to disk.
 	 */
-	offset = i_size & (PAGE_SIZE - 1);
-	if ((page->index >= end_index + 1) || !offset)
+	if (page->index >= nr_pages)
 		goto out;
 
 	zero_user_segment(page, offset, PAGE_SIZE);
-- 
2.18.0.rc1