[RFC PATCH net-next v6 04/14] af_vsock: generalize bind table functions

[Amery Hung]

From: Bobby Eshleman <bobby.eshle...@bytedance.com>

This commit makes the bind table management functions in vsock usable
for different bind tables. Future work will introduce a new table for
datagrams to avoid address collisions, and these functions will be used
there.

Signed-off-by: Bobby Eshleman <bobby.eshle...@bytedance.com>
---
 net/vmw_vsock/af_vsock.c | 34 +++++++++++++++++++++++++++-------
 1 file changed, 27 insertions(+), 7 deletions(-)

diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index acc15e11700c..d571be9cdbf0 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -232,11 +232,12 @@ static void __vsock_remove_connected(struct vsock_sock 
*vsk)
        sock_put(&vsk->sk);
 }
 
-static struct sock *__vsock_find_bound_socket(struct sockaddr_vm *addr)
+static struct sock *vsock_find_bound_socket_common(struct sockaddr_vm *addr,
+                                                  struct list_head *bind_table)
 {
        struct vsock_sock *vsk;
 
-       list_for_each_entry(vsk, vsock_bound_sockets(addr), bound_table) {
+       list_for_each_entry(vsk, bind_table, bound_table) {
                if (vsock_addr_equals_addr(addr, &vsk->local_addr))
                        return sk_vsock(vsk);
 
@@ -249,6 +250,11 @@ static struct sock *__vsock_find_bound_socket(struct 
sockaddr_vm *addr)
        return NULL;
 }
 
+static struct sock *__vsock_find_bound_socket(struct sockaddr_vm *addr)
+{
+       return vsock_find_bound_socket_common(addr, vsock_bound_sockets(addr));
+}
+
 static struct sock *__vsock_find_connected_socket(struct sockaddr_vm *src,
                                                  struct sockaddr_vm *dst)
 {
@@ -671,12 +677,18 @@ static void vsock_pending_work(struct work_struct *work)
 
 /**** SOCKET OPERATIONS ****/
 
-static int __vsock_bind_connectible(struct vsock_sock *vsk,
-                                   struct sockaddr_vm *addr)
+static int vsock_bind_common(struct vsock_sock *vsk,
+                            struct sockaddr_vm *addr,
+                            struct list_head *bind_table,
+                            size_t table_size)
 {
        static u32 port;
        struct sockaddr_vm new_addr;
 
+       if (WARN_ONCE(table_size < VSOCK_HASH_SIZE,
+                     "table size too small, may cause overflow"))
+               return -EINVAL;
+
        if (!port)
                port = get_random_u32_above(LAST_RESERVED_PORT);
 
@@ -692,7 +704,8 @@ static int __vsock_bind_connectible(struct vsock_sock *vsk,
 
                        new_addr.svm_port = port++;
 
-                       if (!__vsock_find_bound_socket(&new_addr)) {
+                       if (!vsock_find_bound_socket_common(&new_addr,
+                                                           
&bind_table[VSOCK_HASH(addr)])) {
                                found = true;
                                break;
                        }
@@ -709,7 +722,8 @@ static int __vsock_bind_connectible(struct vsock_sock *vsk,
                        return -EACCES;
                }
 
-               if (__vsock_find_bound_socket(&new_addr))
+               if (vsock_find_bound_socket_common(&new_addr,
+                                                  
&bind_table[VSOCK_HASH(addr)]))
                        return -EADDRINUSE;
        }
 
@@ -721,11 +735,17 @@ static int __vsock_bind_connectible(struct vsock_sock 
*vsk,
         * by AF_UNIX.
         */
        __vsock_remove_bound(vsk);
-       __vsock_insert_bound(vsock_bound_sockets(&vsk->local_addr), vsk);
+       __vsock_insert_bound(&bind_table[VSOCK_HASH(&vsk->local_addr)], vsk);
 
        return 0;
 }
 
+static int __vsock_bind_connectible(struct vsock_sock *vsk,
+                                   struct sockaddr_vm *addr)
+{
+       return vsock_bind_common(vsk, addr, vsock_bind_table, VSOCK_HASH_SIZE + 
1);
+}
+
 static int __vsock_bind_dgram(struct vsock_sock *vsk,
                              struct sockaddr_vm *addr)
 {
-- 
2.20.1