From 2da338ff752a2789470d733111a5241f30026675 Mon Sep 17 00:00:00 2001
From: Steve French <stfrench@microsoft.com>
Date: Tue, 19 Sep 2023 11:35:53 -0500
Subject: [PATCH 37/50] smb3: do not start laundromat thread when dir leases 
 disabled

When no directory lease support, or for IPC shares where directories
can not be opened, do not start an unneeded laundromat thread for
that mount (it wastes resources).

Fixes: d14de8067e3f ("cifs: Add a laundromat thread for cached directories")
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Acked-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
---
 fs/smb/client/cached_dir.c |  6 ++++++
 fs/smb/client/cifsglob.h   |  2 +-
 fs/smb/client/cifsproto.h  |  2 +-
 fs/smb/client/connect.c    |  8 ++++++--
 fs/smb/client/misc.c       | 14 +++++++++-----
 fs/smb/client/smb2pdu.c    |  2 +-
 6 files changed, 24 insertions(+), 10 deletions(-)

diff --git a/fs/smb/client/cached_dir.c b/fs/smb/client/cached_dir.c
index b17f067e4ada..e2be8aedb26e 100644
--- a/fs/smb/client/cached_dir.c
+++ b/fs/smb/client/cached_dir.c
@@ -452,6 +452,9 @@ void invalidate_all_cached_dirs(struct cifs_tcon *tcon)
 	struct cached_fid *cfid, *q;
 	LIST_HEAD(entry);
 
+	if (cfids == NULL)
+		return;
+
 	spin_lock(&cfids->cfid_list_lock);
 	list_for_each_entry_safe(cfid, q, &cfids->entries, entry) {
 		list_move(&cfid->entry, &entry);
@@ -651,6 +654,9 @@ void free_cached_dirs(struct cached_fids *cfids)
 	struct cached_fid *cfid, *q;
 	LIST_HEAD(entry);
 
+	if (cfids == NULL)
+		return;
+
 	if (cfids->laundromat) {
 		kthread_stop(cfids->laundromat);
 		cfids->laundromat = NULL;
diff --git a/fs/smb/client/cifsglob.h b/fs/smb/client/cifsglob.h
index 032d8716f671..f594fcc0e889 100644
--- a/fs/smb/client/cifsglob.h
+++ b/fs/smb/client/cifsglob.h
@@ -1943,7 +1943,7 @@ require use of the stronger protocol */
  * cifsInodeInfo->lock_sem	cifsInodeInfo->llist		cifs_init_once
  *				->can_cache_brlcks
  * cifsInodeInfo->deferred_lock	cifsInodeInfo->deferred_closes	cifsInodeInfo_alloc
- * cached_fid->fid_mutex		cifs_tcon->crfid		tconInfoAlloc
+ * cached_fid->fid_mutex		cifs_tcon->crfid		tcon_info_alloc
  * cifsFileInfo->fh_mutex		cifsFileInfo			cifs_new_fileinfo
  * cifsFileInfo->file_info_lock	cifsFileInfo->count		cifs_new_fileinfo
  *				->invalidHandle			initiate_cifs_search
diff --git a/fs/smb/client/cifsproto.h b/fs/smb/client/cifsproto.h
index 7d8035846680..0c37eefa18a5 100644
--- a/fs/smb/client/cifsproto.h
+++ b/fs/smb/client/cifsproto.h
@@ -512,7 +512,7 @@ extern int CIFSSMBLogoff(const unsigned int xid, struct cifs_ses *ses);
 
 extern struct cifs_ses *sesInfoAlloc(void);
 extern void sesInfoFree(struct cifs_ses *);
-extern struct cifs_tcon *tconInfoAlloc(void);
+extern struct cifs_tcon *tcon_info_alloc(bool dir_leases_enabled);
 extern void tconInfoFree(struct cifs_tcon *);
 
 extern int cifs_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server,
diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c
index 687754791bf0..3902e90dca6b 100644
--- a/fs/smb/client/connect.c
+++ b/fs/smb/client/connect.c
@@ -1882,7 +1882,8 @@ cifs_setup_ipc(struct cifs_ses *ses, struct smb3_fs_context *ctx)
 		}
 	}
 
-	tcon = tconInfoAlloc();
+	/* no need to setup directory caching on IPC share, so pass in false */
+	tcon = tcon_info_alloc(false);
 	if (tcon == NULL)
 		return -ENOMEM;
 
@@ -2492,7 +2493,10 @@ cifs_get_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
 		goto out_fail;
 	}
 
-	tcon = tconInfoAlloc();
+	if (ses->server->capabilities & SMB2_GLOBAL_CAP_DIRECTORY_LEASING)
+		tcon = tcon_info_alloc(true);
+	else
+		tcon = tcon_info_alloc(false);
 	if (tcon == NULL) {
 		rc = -ENOMEM;
 		goto out_fail;
diff --git a/fs/smb/client/misc.c b/fs/smb/client/misc.c
index 366b755ca913..35b176457bbe 100644
--- a/fs/smb/client/misc.c
+++ b/fs/smb/client/misc.c
@@ -113,18 +113,22 @@ sesInfoFree(struct cifs_ses *buf_to_free)
 }
 
 struct cifs_tcon *
-tconInfoAlloc(void)
+tcon_info_alloc(bool dir_leases_enabled)
 {
 	struct cifs_tcon *ret_buf;
 
 	ret_buf = kzalloc(sizeof(*ret_buf), GFP_KERNEL);
 	if (!ret_buf)
 		return NULL;
-	ret_buf->cfids = init_cached_dirs();
-	if (!ret_buf->cfids) {
-		kfree(ret_buf);
-		return NULL;
+
+	if (dir_leases_enabled == true) {
+		ret_buf->cfids = init_cached_dirs();
+		if (!ret_buf->cfids) {
+			kfree(ret_buf);
+			return NULL;
+		}
 	}
+	/* else ret_buf->cfids is already set to NULL above */
 
 	atomic_inc(&tconInfoAllocCount);
 	ret_buf->status = TID_NEW;
diff --git a/fs/smb/client/smb2pdu.c b/fs/smb/client/smb2pdu.c
index 44d4943e9c56..405ea324f28d 100644
--- a/fs/smb/client/smb2pdu.c
+++ b/fs/smb/client/smb2pdu.c
@@ -3878,7 +3878,7 @@ void smb2_reconnect_server(struct work_struct *work)
 		goto done;
 
 	/* allocate a dummy tcon struct used for reconnect */
-	tcon = tconInfoAlloc();
+	tcon = tcon_info_alloc(false);
 	if (!tcon) {
 		resched = true;
 		list_for_each_entry_safe(ses, ses2, &tmp_ses_list, rlist) {
-- 
2.39.2

