summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorPavel Shilovsky <piastryyy@gmail.com>2019-03-04 17:48:01 -0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-03-23 08:44:35 +0100
commitb1faf3d2b5b4f81eeee6b367076d243adf87859f (patch)
treec4645dc0c9bb6f1c162ed98106f5c864a1f77978
parenta2ef87f9d268190e27580ec5ede7cbf7dd6702aa (diff)
CIFS: Fix read after write for files with read caching
commit 6dfbd84684700cb58b34e8602c01c12f3d2595c8 upstream. When we have a READ lease for a file and have just issued a write operation to the server we need to purge the cache and set oplock/lease level to NONE to avoid reading stale data. Currently we do that only if a write operation succedeed thus not covering cases when a request was sent to the server but a negative error code was returned later for some other reasons (e.g. -EIOCBQUEUED or -EINTR). Fix this by turning off caching regardless of the error code being returned. The patches fixes generic tests 075 and 112 from the xfs-tests. Cc: <stable@vger.kernel.org> Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--fs/cifs/file.c12
1 files changed, 7 insertions, 5 deletions
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 1062e96ee272..0305e3866216 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -2753,14 +2753,16 @@ cifs_strict_writev(struct kiocb *iocb, struct iov_iter *from)
* these pages but not on the region from pos to ppos+len-1.
*/
written = cifs_user_writev(iocb, from);
- if (written > 0 && CIFS_CACHE_READ(cinode)) {
+ if (CIFS_CACHE_READ(cinode)) {
/*
- * Windows 7 server can delay breaking level2 oplock if a write
- * request comes - break it on the client to prevent reading
- * an old data.
+ * We have read level caching and we have just sent a write
+ * request to the server thus making data in the cache stale.
+ * Zap the cache and set oplock/lease level to NONE to avoid
+ * reading stale data from the cache. All subsequent read
+ * operations will read new data from the server.
*/
cifs_zap_mapping(inode);
- cifs_dbg(FYI, "Set no oplock for inode=%p after a write operation\n",
+ cifs_dbg(FYI, "Set Oplock/Lease to NONE for inode=%p after write\n",
inode);
cinode->oplock = 0;
}