ksmbd: replace connection list with xarray

Replace connection list with xarray to improve lookup performance.

Signed-off-by: Namjae Jeon <[email protected]>

Author: namjaejeon

connection.c

@@ -22,7 +22,7 @@ static DEFINE_MUTEX(init_lock);
 
 static struct ksmbd_conn_ops default_conn_ops;
 
-LIST_HEAD(conn_list);
+DEFINE_XARRAY(conn_list);
 DECLARE_RWSEM(conn_list_lock);
 
 /**
@@ -36,7 +36,7 @@ DECLARE_RWSEM(conn_list_lock);
 void ksmbd_conn_free(struct ksmbd_conn *conn)
 {
 	down_write(&conn_list_lock);
-	list_del(&conn->conns_list);
+	xa_erase(&conn_list, conn->inet_addr);
 	up_write(&conn_list_lock);
 
 	xa_destroy(&conn->sessions);
@@ -53,9 +53,10 @@ void ksmbd_conn_free(struct ksmbd_conn *conn)
  *
  * Return:	ksmbd_conn struct on success, otherwise NULL
  */
-struct ksmbd_conn *ksmbd_conn_alloc(void)
+struct ksmbd_conn *ksmbd_conn_alloc(__be32 inet_addr)
 {
 	struct ksmbd_conn *conn;
+	int err;
 
 	conn = kzalloc(sizeof(struct ksmbd_conn), KSMBD_DEFAULT_GFP);
 	if (!conn)
@@ -81,6 +82,7 @@ struct ksmbd_conn *ksmbd_conn_alloc(void)
 	atomic_set(&conn->refcnt, 1);
 	conn->total_credits = 1;
 	conn->outstanding_credits = 0;
+	conn->inet_addr = inet_addr;
 
 	init_waitqueue_head(&conn->req_running_q);
 	init_waitqueue_head(&conn->r_count_q);
@@ -98,7 +100,14 @@ struct ksmbd_conn *ksmbd_conn_alloc(void)
 	init_rwsem(&conn->session_lock);
 
 	down_write(&conn_list_lock);
-	list_add(&conn->conns_list, &conn_list);
+	err = xa_err(xa_store(&conn_list, inet_addr, conn, KSMBD_DEFAULT_GFP));
+	if (err < 0) {
+		if (IS_ENABLED(CONFIG_UNICODE))
+			utf8_unload(conn->um);
+		unload_nls(conn->local_nls);
+		kfree(conn);
+		conn = NULL;
+	}
 	up_write(&conn_list_lock);
 	return conn;
 }
@@ -107,9 +116,10 @@ bool ksmbd_conn_lookup_dialect(struct ksmbd_conn *c)
 {
 	struct ksmbd_conn *t;
 	bool ret = false;
+	unsigned long idx;
 
 	down_read(&conn_list_lock);
-	list_for_each_entry(t, &conn_list, conns_list) {
+	xa_for_each(&conn_list, idx, t) {
 		if (memcmp(t->ClientGUID, c->ClientGUID, SMB2_CLIENT_GUID_SIZE))
 			continue;
 
@@ -181,9 +191,10 @@ void ksmbd_conn_unlock(struct ksmbd_conn *conn)
 void ksmbd_all_conn_set_status(u64 sess_id, u32 status)
 {
 	struct ksmbd_conn *conn;
+	unsigned long idx;
 
 	down_read(&conn_list_lock);
-	list_for_each_entry(conn, &conn_list, conns_list) {
+	xa_for_each(&conn_list, idx, conn) {
 		if (conn->binding || xa_load(&conn->sessions, sess_id))
 			WRITE_ONCE(conn->status, status);
 	}
@@ -198,6 +209,7 @@ void ksmbd_conn_wait_idle(struct ksmbd_conn *conn)
 int ksmbd_conn_wait_idle_sess_id(struct ksmbd_conn *curr_conn, u64 sess_id)
 {
 	struct ksmbd_conn *conn;
+	unsigned long idx;
 	int rc, retry_count = 0, max_timeout = 120;
 	int rcount = 1;
 
@@ -206,7 +218,7 @@ int ksmbd_conn_wait_idle_sess_id(struct ksmbd_conn *curr_conn, u64 sess_id)
 		return -EIO;
 
 	down_read(&conn_list_lock);
-	list_for_each_entry(conn, &conn_list, conns_list) {
+	xa_for_each(&conn_list, idx, conn) {
 		if (conn->binding || xa_load(&conn->sessions, sess_id)) {
 			if (conn == curr_conn)
 				rcount = 2;
@@ -532,10 +544,11 @@ static void stop_sessions(void)
 {
 	struct ksmbd_conn *conn;
 	struct ksmbd_transport *t;
+	unsigned long idx;
 
 again:
 	down_read(&conn_list_lock);
-	list_for_each_entry(conn, &conn_list, conns_list) {
+	xa_for_each(&conn_list, idx, conn) {
 		t = conn->transport;
 		ksmbd_conn_set_exiting(conn);
 		if (t->ops->shutdown) {
@@ -546,7 +559,7 @@ static void stop_sessions(void)
 	}
 	up_read(&conn_list_lock);
 
-	if (!list_empty(&conn_list)) {
+	if (!xa_empty(&conn_list)) {
 		msleep(100);
 		goto again;
 	}

connection.h

@@ -146,13 +146,13 @@ struct ksmbd_transport {
 #define KSMBD_TCP_SEND_TIMEOUT	(5 * HZ)
 #define KSMBD_TCP_PEER_SOCKADDR(c)	((struct sockaddr *)&((c)->peer_addr))
 
-extern struct list_head conn_list;
+extern struct xarray conn_list;
 extern struct rw_semaphore conn_list_lock;
 
 bool ksmbd_conn_alive(struct ksmbd_conn *conn);
 void ksmbd_conn_wait_idle(struct ksmbd_conn *conn);
 int ksmbd_conn_wait_idle_sess_id(struct ksmbd_conn *curr_conn, u64 sess_id);
-struct ksmbd_conn *ksmbd_conn_alloc(void);
+struct ksmbd_conn *ksmbd_conn_alloc(__be32 inet_addr);
 void ksmbd_conn_free(struct ksmbd_conn *conn);
 bool ksmbd_conn_lookup_dialect(struct ksmbd_conn *c);
 int ksmbd_conn_write(struct ksmbd_work *work);

smb1pdu.c

@@ -1658,6 +1658,7 @@ int smb_locking_andx(struct ksmbd_work *work)
 	int locked, timeout;
 	const unsigned long long loff_max = ~0;
 	struct ksmbd_conn *conn;
+	unsigned long idx;
 
 	timeout = le32_to_cpu(req->Timeout);
 	ksmbd_debug(SMB, "got oplock brk for fid %d lock type = 0x%x, timeout: %d\n",
@@ -1782,7 +1783,7 @@ int smb_locking_andx(struct ksmbd_work *work)
 		list_del(&smb_lock->llist);
 		/* check locks in connections */
 		down_read(&conn_list_lock);
-		list_for_each_entry(conn, &conn_list, conns_list) {
+		xa_each_each(&conn_list, idx, conn) {
 			spin_lock(&conn->llist_lock);
 			list_for_each_entry_safe(cmp_lock, tmp2, &conn->lock_list, clist) {
 				if (file_inode(cmp_lock->fl->fl_file) !=
@@ -1948,7 +1949,7 @@ int smb_locking_andx(struct ksmbd_work *work)
 
 		locked = 0;
 		up_read(&conn_list_lock);
-		list_for_each_entry(conn, &conn_list, conns_list) {
+		xa_each_each(&conn_list, idx, conn) {
 			spin_lock(&conn->llist_lock);
 			list_for_each_entry(cmp_lock, &conn->lock_list, clist) {
 				if (file_inode(cmp_lock->fl->fl_file) !=

smb2pdu.c

@@ -7901,6 +7901,7 @@ int smb2_lock(struct ksmbd_work *work)
 	struct ksmbd_file *fp = NULL;
 	struct file_lock *flock = NULL;
 	struct file *filp = NULL;
+	unsigned long idx;
 	int lock_count;
 	int flags = 0;
 	int cmd = 0;
@@ -8026,7 +8027,7 @@ int smb2_lock(struct ksmbd_work *work)
 		nolock = 1;
 		/* check locks in connection list */
 		down_read(&conn_list_lock);
-		list_for_each_entry(conn, &conn_list, conns_list) {
+		xa_for_each(&conn_list, idx, conn) {
 			spin_lock(&conn->llist_lock);
 			list_for_each_entry_safe(cmp_lock, tmp2, &conn->lock_list, clist) {
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 9, 0)

transport_rdma.c

@@ -371,7 +371,7 @@ static struct smb_direct_transport *alloc_transport(struct rdma_cm_id *cm_id)
 	INIT_WORK(&t->send_immediate_work, smb_direct_send_immediate_work);
 	INIT_WORK(&t->disconnect_work, smb_direct_disconnect_rdma_work);
 
-	conn = ksmbd_conn_alloc();
+	conn = ksmbd_conn_alloc(0);
 	if (!conn)
 		goto err;
 	conn->transport = KSMBD_TRANS(t);

transport_tcp.c

@@ -109,13 +109,12 @@ static struct tcp_transport *alloc_transport(struct socket *client_sk)
 		return NULL;
 	t->sock = client_sk;
 
-	conn = ksmbd_conn_alloc();
+	conn = ksmbd_conn_alloc(inet_sk(client_sk->sk)->inet_daddr);
 	if (!conn) {
 		kfree(t);
 		return NULL;
 	}
 
-	conn->inet_addr = inet_sk(client_sk->sk)->inet_daddr;
 	conn->transport = KSMBD_TRANS(t);
 	KSMBD_TRANS(t)->conn = conn;
 	KSMBD_TRANS(t)->ops = &ksmbd_tcp_transport_ops;
@@ -284,14 +283,12 @@ static int ksmbd_kthread_fn(void *p)
 		 */
 		csk_inet = inet_sk(client_sk->sk);
 		down_read(&conn_list_lock);
-		list_for_each_entry(conn, &conn_list, conns_list)
-			if (csk_inet->inet_daddr == conn->inet_addr) {
-				ret = -EAGAIN;
-				break;
-			}
-		up_read(&conn_list_lock);
-		if (ret == -EAGAIN)
+		conn = xa_load(&conn_list, csk_inet->inet_daddr);
+		if (conn) {
+			up_read(&conn_list_lock);
 			continue;
+		}
+		up_read(&conn_list_lock);
 
 		if (server_conf.max_connections &&
 		    atomic_inc_return(&active_num_conn) >= server_conf.max_connections) {