[PATCH 1/4] ksmbd: advertise SMB2_GLOBAL_CAP_PERSISTENT_HANDLES

[Yunseong Kim <yunseong.kim@est.tech>]

Advertise SMB2_GLOBAL_CAP_PERSISTENT_HANDLES in the SMB2 negotiate
response when durable handles are enabled globally. This tells clients
that the server supports persistent handles, which is a prerequisite
for Continuously Available (CA) share functionality.

The capability is gated by KSMBD_GLOBAL_FLAG_DURABLE_HANDLE (controlled
by 'durable handles = yes' in ksmbd.conf) so administrators must
explicitly enable it.

Signed-off-by: Yunseong Kim <yunseong.kim@est.tech>
---
 fs/smb/server/smb2ops.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/fs/smb/server/smb2ops.c b/fs/smb/server/smb2ops.c
index 4578291fb172..414153fa2a68 100644
--- a/fs/smb/server/smb2ops.c
+++ b/fs/smb/server/smb2ops.c
@@ -270,10 +270,8 @@ void init_smb3_02_server(struct ksmbd_conn *conn)
 	if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB3_MULTICHANNEL)
 		conn->vals->req_capabilities |= SMB2_GLOBAL_CAP_MULTI_CHANNEL;
 
-	/*
-	 * Durable handles are in-memory only.  Do not advertise persistent
-	 * handles until CA recovery and fencing are implemented.
-	 */
+	if (server_conf.flags & KSMBD_GLOBAL_FLAG_DURABLE_HANDLE)
+		conn->vals->req_capabilities |= SMB2_GLOBAL_CAP_PERSISTENT_HANDLES;
 }
 
 /**
@@ -296,7 +294,9 @@ int init_smb3_11_server(struct ksmbd_conn *conn)
 	if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB3_MULTICHANNEL)
 		conn->vals->req_capabilities |= SMB2_GLOBAL_CAP_MULTI_CHANNEL;
 
-	/* See init_smb3_02_server(): persistent handles require CA recovery. */
+	if (server_conf.flags & KSMBD_GLOBAL_FLAG_DURABLE_HANDLE)
+		conn->vals->req_capabilities |= SMB2_GLOBAL_CAP_PERSISTENT_HANDLES;
+
 	return 0;
 }
 

-- 
2.47.3