summaryrefslogtreecommitdiff
path: root/fs/cifs/file.c
diff options
context:
space:
mode:
authorPavel Shilovsky <pshilov@microsoft.com>2019-10-29 16:51:19 -0700
committerSteve French <stfrench@microsoft.com>2019-11-25 01:17:12 -0600
commit9bd4540836684013aaad6070a65d6fcdd9006625 (patch)
tree93f7efa7ff635683f5120f961cde3b852fc27f42 /fs/cifs/file.c
parent32546a9586aa4565035bb557e191648e022b29e8 (diff)
CIFS: Properly process SMB3 lease breaks
Currenly we doesn't assume that a server may break a lease from RWH to RW which causes us setting a wrong lease state on a file and thus mistakenly flushing data and byte-range locks and purging cached data on the client. This leads to performance degradation because subsequent IOs go directly to the server. Fix this by propagating new lease state and epoch values to the oplock break handler through cifsFileInfo structure and removing the use of cifsInodeInfo flags for that. It allows to avoid some races of several lease/oplock breaks using those flags in parallel. Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
Diffstat (limited to 'fs/cifs/file.c')
-rw-r--r--fs/cifs/file.c10
1 files changed, 7 insertions, 3 deletions
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 776d9e5be020..f1fe9c44d298 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -4730,12 +4730,13 @@ void cifs_oplock_break(struct work_struct *work)
struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
struct TCP_Server_Info *server = tcon->ses->server;
int rc = 0;
+ bool purge_cache = false;
wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS,
TASK_UNINTERRUPTIBLE);
- server->ops->downgrade_oplock(server, cinode,
- test_bit(CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2, &cinode->flags));
+ server->ops->downgrade_oplock(server, cinode, cfile->oplock_level,
+ cfile->oplock_epoch, &purge_cache);
if (!CIFS_CACHE_WRITE(cinode) && CIFS_CACHE_READ(cinode) &&
cifs_has_mand_locks(cinode)) {
@@ -4750,18 +4751,21 @@ void cifs_oplock_break(struct work_struct *work)
else
break_lease(inode, O_WRONLY);
rc = filemap_fdatawrite(inode->i_mapping);
- if (!CIFS_CACHE_READ(cinode)) {
+ if (!CIFS_CACHE_READ(cinode) || purge_cache) {
rc = filemap_fdatawait(inode->i_mapping);
mapping_set_error(inode->i_mapping, rc);
cifs_zap_mapping(inode);
}
cifs_dbg(FYI, "Oplock flush inode %p rc %d\n", inode, rc);
+ if (CIFS_CACHE_WRITE(cinode))
+ goto oplock_break_ack;
}
rc = cifs_push_locks(cfile);
if (rc)
cifs_dbg(VFS, "Push locks rc = %d\n", rc);
+oplock_break_ack:
/*
* releasing stale oplock after recent reconnect of smb session using
* a now incorrect file handle is not a data integrity issue but do