2019-05-31 16:13:21

by Liu Xiang

[permalink] [raw]
Subject: [PATCH v2] fs: buffer: fix fully_mapped reset in block_read_full_page()

Because get_block() might set the buffer mapped, fully_mapped reset
should be done according to the result of buffer_mapped(bh)
which check the buffer mapped attribute again after get_block().

Signed-off-by: Liu Xiang <[email protected]>
---

Changes in v2:
change comment

fs/buffer.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/buffer.c b/fs/buffer.c
index e450c55..987aadb 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -2243,7 +2243,6 @@ int block_read_full_page(struct page *page, get_block_t *get_block)
if (!buffer_mapped(bh)) {
int err = 0;

- fully_mapped = 0;
if (iblock < lblock) {
WARN_ON(bh->b_size != blocksize);
err = get_block(inode, iblock, bh, 0);
@@ -2251,6 +2250,7 @@ int block_read_full_page(struct page *page, get_block_t *get_block)
SetPageError(page);
}
if (!buffer_mapped(bh)) {
+ fully_mapped = 0;
zero_user(page, i * blocksize, blocksize);
if (!err)
set_buffer_uptodate(bh);
--
1.9.1