[PATCH 08/14] cifs: account for primary channel in the interface list

nspmangalore
2023-10-30T11:00:52Z

From: Shyam Prasad N <sprasad@microsoft.com>

The refcounting of server interfaces should account
for the primary channel too. Although this is not
strictly necessary, doing so will account for the primary
channel in DebugData.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
---
fs/smb/client/sess.c | 23 +++++++++++++++++++++++
fs/smb/client/smb2ops.c | 6 ++++++
2 files changed, 29 insertions(+)

diff --git a/fs/smb/client/sess.c b/fs/smb/client/sess.c
index d009994f82cf..6843deed6119 100644
--- a/fs/smb/client/sess.c
+++ b/fs/smb/client/sess.c
@@ -332,6 +332,16 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)

/* then look for a new one */
list_for_each_entry(iface, &ses->iface_list, iface_head) {
+ if (!chan_index) {
+ /* if we're trying to get the updated iface for primary channel */
+ if (!cifs_match_ipaddr((struct sockaddr *) &server->dstaddr,
+ (struct sockaddr *) &iface->sockaddr))
+ continue;
+
+ kref_get(&iface->refcount);
+ break;
+ }
+
/* do not mix rdma and non-rdma interfaces */
if (iface->rdma_capable != server->rdma)
continue;
@@ -358,6 +368,13 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
cifs_dbg(FYI, "unable to find a suitable iface\n");
}

+ if (!chan_index && !iface) {
+ cifs_dbg(VFS, "unable to get the interface matching: %pIS\n",
+ &server->dstaddr);
+ spin_unlock(&ses->iface_lock);
+ return 0;
+ }
+
/* now drop the ref to the current iface */
if (old_iface && iface) {
cifs_dbg(FYI, "replacing iface: %pIS with %pIS\n",
@@ -380,6 +397,12 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
old_iface->weight_fulfilled--;

kref_put(&old_iface->refcount, release_iface);
+ } else if (!chan_index) {
+ /* special case: update interface for primary channel */
+ cifs_dbg(FYI, "referencing primary channel iface: %pIS\n",
+ &iface->sockaddr);
+ iface->num_channels++;
+ iface->weight_fulfilled++;
} else {
WARN_ON(!iface);
cifs_dbg(FYI, "adding new iface: %pIS\n", &iface->sockaddr);
diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c
index 9aeecee6b91b..e7e1e0e5bdfe 100644
--- a/fs/smb/client/smb2ops.c
+++ b/fs/smb/client/smb2ops.c
@@ -756,6 +756,7 @@ SMB3_request_interfaces(const unsigned int xid, struct cifs_tcon *tcon, bool in_
unsigned int ret_data_len = 0;
struct network_interface_info_ioctl_rsp *out_buf = NULL;
struct cifs_ses *ses = tcon->ses;
+ struct TCP_Server_Info *pserver;

/* do not query too frequently */
if (ses->iface_last_update &&
@@ -780,6 +781,11 @@ SMB3_request_interfaces(const unsigned int xid, struct cifs_tcon *tcon, bool in_
if (rc)
goto out;

+ /* check if iface is still active */
+ pserver = ses->chans[0].server;
+ if (pserver && !cifs_chan_is_iface_active(ses, pserver))
+ cifs_chan_update_iface(ses, pserver);
+
out:
kfree(out_buf);
return rc;
--
2.34.1