From 0bacbe528e26422e424d110ebda4ec68ea0fd5eb Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 2 Feb 2016 02:28:05 +0000 Subject: [PATCH] affs_do_readpage_ofs(): just use kmap_atomic() around memcpy() It forgets kunmap() on a failure exit, but there's really no point keeping the page kmapped at all - after all, what we are doing is a bunch of memcpy() into the parts of page, so kmap_atomic()/kunmap_atomic() just around those memcpy() is enough. Spotted-by: Insu Yun Signed-off-by: Al Viro --- fs/affs/file.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/fs/affs/file.c b/fs/affs/file.c index 0548c53f41d5..22fc7c802d69 100644 --- a/fs/affs/file.c +++ b/fs/affs/file.c @@ -511,8 +511,6 @@ affs_do_readpage_ofs(struct page *page, unsigned to) pr_debug("%s(%lu, %ld, 0, %d)\n", __func__, inode->i_ino, page->index, to); BUG_ON(to > PAGE_CACHE_SIZE); - kmap(page); - data = page_address(page); bsize = AFFS_SB(sb)->s_data_blksize; tmp = page->index << PAGE_CACHE_SHIFT; bidx = tmp / bsize; @@ -524,14 +522,15 @@ affs_do_readpage_ofs(struct page *page, unsigned to) return PTR_ERR(bh); tmp = min(bsize - boff, to - pos); BUG_ON(pos + tmp > to || tmp > bsize); + data = kmap_atomic(page); memcpy(data + pos, AFFS_DATA(bh) + boff, tmp); + kunmap_atomic(data); affs_brelse(bh); bidx++; pos += tmp; boff = 0; } flush_dcache_page(page); - kunmap(page); return 0; } -- 2.20.1