ceph: Avoid data inconsistency due to d-cache aliasing in readpage()

If the length of data to be read in readpage() is exactly
PAGE_CACHE_SIZE, the original code does not flush d-cache
for data consistency after finishing reading. This patches fixes
this.

Signed-off-by: Li Wang <liwang@ubuntukylin.com>
Signed-off-by: Sage Weil <sage@inktank.com>
This commit is contained in:
Li Wang 2013-11-13 15:22:14 +08:00 committed by Sage Weil
parent 86b58d1313
commit 56f91aad69
1 changed files with 6 additions and 2 deletions

View File

@ -210,9 +210,13 @@ static int readpage_nounlock(struct file *filp, struct page *page)
if (err < 0) {
SetPageError(page);
goto out;
} else if (err < PAGE_CACHE_SIZE) {
} else {
if (err < PAGE_CACHE_SIZE) {
/* zero fill remainder of page */
zero_user_segment(page, err, PAGE_CACHE_SIZE);
zero_user_segment(page, err, PAGE_CACHE_SIZE);
} else {
flush_dcache_page(page);
}
}
SetPageUptodate(page);