From 3d4ef9a15343f038ccae17f60468569f23113312 Mon Sep 17 00:00:00 2001 From: Steve French Date: Wed, 25 Apr 2018 22:19:09 -0500 Subject: smb3: fix redundant opens on root In SMB2/SMB3 unlike in cifs we unnecessarily open the root of the share over and over again in various places during mount and path revalidation and also in statfs. This patch cuts redundant traffic (opens and closes) by simply keeping the directory handle for the root around (and reopening it as needed on reconnect), so query calls don't require three round trips to copmlete - just one, and eases load on network, client and server (on mount alone, cuts network traffic by more than a third). Also add a new cifs mount parm "nohandlecache" to allow users whose servers might have resource constraints (eg in case they have a server with so many users connecting to it that this extra handle per mount could possibly be a resource concern). Signed-off-by: Steve French Reviewed-by: Ronnie Sahlberg --- fs/cifs/cifssmb.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'fs/cifs/cifssmb.c') diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c index 1529a088383d..c8e42785d261 100644 --- a/fs/cifs/cifssmb.c +++ b/fs/cifs/cifssmb.c @@ -106,6 +106,12 @@ cifs_mark_open_files_invalid(struct cifs_tcon *tcon) open_file->oplock_break_cancelled = true; } spin_unlock(&tcon->open_file_lock); + + mutex_lock(&tcon->prfid_mutex); + tcon->valid_root_fid = false; + memset(tcon->prfid, 0, sizeof(struct cifs_fid)); + mutex_unlock(&tcon->prfid_mutex); + /* * BB Add call to invalidate_inodes(sb) for all superblocks mounted * to this tcon. -- cgit v1.2.3-70-g09d2