From: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Date: Sun, 7 Feb 2021 19:04:22 +0000 (-0800)
Subject: ext4: use memcpy_from_page() in pagecache_read()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=4d93874b9e9ce582fd4401334c88eaf93b6dff43;p=linux.git

ext4: use memcpy_from_page() in pagecache_read()

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210207190425.38107-6-chaitanya.kulkarni@wdc.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
---

diff --git a/fs/ext4/verity.c b/fs/ext4/verity.c
index 00e3cbde472e4..daf88669a2e9e 100644
--- a/fs/ext4/verity.c
+++ b/fs/ext4/verity.c
@@ -45,16 +45,13 @@ static int pagecache_read(struct inode *inode, void *buf, size_t count,
 		size_t n = min_t(size_t, count,
 				 PAGE_SIZE - offset_in_page(pos));
 		struct page *page;
-		void *addr;
 
 		page = read_mapping_page(inode->i_mapping, pos >> PAGE_SHIFT,
 					 NULL);
 		if (IS_ERR(page))
 			return PTR_ERR(page);
 
-		addr = kmap_atomic(page);
-		memcpy(buf, addr + offset_in_page(pos), n);
-		kunmap_atomic(addr);
+		memcpy_from_page(buf, page, offset_in_page(pos), n);
 
 		put_page(page);