cifs: always iterate smb sessions using primary channel

smb sessions and tcons currently hang off primary channel only.
Secondary channels have the lists as empty. Whenever there's a
need to iterate sessions or tcons, we should use the list in the
corresponding primary channel.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>

Author: sprasad-microsoft

fs/cifs/misc.c

@@ -400,6 +400,7 @@ is_valid_oplock_break(char *buffer, struct TCP_Server_Info *srv)
 {
 	struct smb_hdr *buf = (struct smb_hdr *)buffer;
 	struct smb_com_lock_req *pSMB = (struct smb_com_lock_req *)buf;
+	struct TCP_Server_Info *pserver;
 	struct cifs_ses *ses;
 	struct cifs_tcon *tcon;
 	struct cifsInodeInfo *pCifsInode;
@@ -464,9 +465,12 @@ is_valid_oplock_break(char *buffer, struct TCP_Server_Info *srv)
 	if (!(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE))
 		return false;
 
+	/* If server is a channel, select the primary channel */
+	pserver = CIFS_SERVER_IS_CHAN(srv) ? srv->primary_server : srv;
+
 	/* look up tcon based on tid & uid */
 	spin_lock(&cifs_tcp_ses_lock);
-	list_for_each_entry(ses, &srv->smb_ses_list, smb_ses_list) {
+	list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
 		list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 			if (tcon->tid != buf->Tid)
 				continue;

fs/cifs/smb2misc.c

@@ -135,6 +135,7 @@ static __u32 get_neg_ctxt_len(struct smb2_hdr *hdr, __u32 len,
 int
 smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *server)
 {
+	struct TCP_Server_Info *pserver;
 	struct smb2_hdr *shdr = (struct smb2_hdr *)buf;
 	struct smb2_pdu *pdu = (struct smb2_pdu *)shdr;
 	int hdr_size = sizeof(struct smb2_hdr);
@@ -143,6 +144,9 @@ smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *server)
 	__u32 calc_len; /* calculated length */
 	__u64 mid;
 
+	/* If server is a channel, select the primary channel */
+	pserver = CIFS_SERVER_IS_CHAN(server) ? server->primary_server : server;
+
 	/*
 	 * Add function to do table lookup of StructureSize by command
 	 * ie Validate the wct via smb2_struct_sizes table above
@@ -155,7 +159,7 @@ smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *server)
 
 		/* decrypt frame now that it is completely read in */
 		spin_lock(&cifs_tcp_ses_lock);
-		list_for_each_entry(iter, &server->smb_ses_list, smb_ses_list) {
+		list_for_each_entry(iter, &pserver->smb_ses_list, smb_ses_list) {
 			if (iter->Suid == le64_to_cpu(thdr->SessionId)) {
 				ses = iter;
 				break;
@@ -671,6 +675,7 @@ bool
 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 {
 	struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
+	struct TCP_Server_Info *pserver;
 	struct cifs_ses *ses;
 	struct cifs_tcon *tcon;
 	struct cifsInodeInfo *cinode;
@@ -691,9 +696,12 @@ smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 
 	cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
 
+	/* If server is a channel, select the primary channel */
+	pserver = CIFS_SERVER_IS_CHAN(server) ? server->primary_server : server;
+
 	/* look up tcon based on tid & uid */
 	spin_lock(&cifs_tcp_ses_lock);
-	list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
+	list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
 		list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 
 			spin_lock(&tcon->open_file_lock);

fs/cifs/smb2ops.c

@@ -2302,14 +2302,18 @@ static void
 smb2_is_network_name_deleted(char *buf, struct TCP_Server_Info *server)
 {
 	struct smb2_hdr *shdr = (struct smb2_hdr *)buf;
+	struct TCP_Server_Info *pserver;
 	struct cifs_ses *ses;
 	struct cifs_tcon *tcon;
 
 	if (shdr->Status != STATUS_NETWORK_NAME_DELETED)
 		return;
 
+	/* If server is a channel, select the primary channel */
+	pserver = CIFS_SERVER_IS_CHAN(server) ? server->primary_server : server;
+
 	spin_lock(&cifs_tcp_ses_lock);
-	list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
+	list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
 		list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 			if (tcon->tid == le32_to_cpu(shdr->Id.SyncId.TreeId)) {
 				spin_lock(&tcon->tc_lock);

fs/cifs/smb2transport.c

@@ -136,9 +136,13 @@ int smb2_get_sign_key(__u64 ses_id, struct TCP_Server_Info *server, u8 *key)
 static struct cifs_ses *
 smb2_find_smb_ses_unlocked(struct TCP_Server_Info *server, __u64 ses_id)
 {
+	struct TCP_Server_Info *pserver;
 	struct cifs_ses *ses;
 
-	list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
+	/* If server is a channel, select the primary channel */
+	pserver = CIFS_SERVER_IS_CHAN(server) ? server->primary_server : server;
+
+	list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
 		if (ses->Suid != ses_id)
 			continue;
 		++ses->ses_count;