[DLM] fix lowcomms receiving

This patch fixes a bug whereby data on a newly accepted connection would be
ignored if it arrived soon after the accept.

Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 13 insertions, 11 deletions

diff --git a/fs/dlm/lowcomms-tcp.c b/fs/dlm/lowcomms-tcp.c
index 6e27201f2f95..8e6a76cf1805 100644
--- a/fs/dlm/lowcomms-tcp.c
+++ b/fs/dlm/lowcomms-tcp.c
@@ -327,6 +327,9 @@ static int receive_from_sock(struct connection *con)
 
         if (ret <= 0)
                 goto out_close;
+        if (ret == -EAGAIN)
+                goto out_resched;
+
         if (ret == len)
                 call_again_soon = 1;
         cbuf_add(&con->cb, ret);
@@ -359,8 +362,7 @@ out_resched:
         if (!test_and_set_bit(CF_READ_PENDING, &con->flags))
                 queue_work(recv_workqueue, &con->rwork);
         up_read(&con->sock_sem);
-        cond_resched();
-        return 0;
+        return -EAGAIN;
 
 out_close:
         up_read(&con->sock_sem);
@@ -381,6 +383,7 @@ static int accept_from_sock(struct connection *con)
         int len;
         int nodeid;
         struct connection *newcon;
+        struct connection *addcon;
 
         memset(&peeraddr, 0, sizeof(peeraddr));
         result = sock_create_kern(dlm_local_addr.ss_family, SOCK_STREAM,
@@ -454,12 +457,13 @@ static int accept_from_sock(struct connection *con)
                 othercon->sock = newsock;
                 newsock->sk->sk_user_data = othercon;
                 add_sock(newsock, othercon);
+                addcon = othercon;
         }
         else {
                 newsock->sk->sk_user_data = newcon;
                 newcon->rx_action = receive_from_sock;
                 add_sock(newsock, newcon);
-
+                addcon = newcon;
         }
 
         up_write(&newcon->sock_sem);
@@ -469,8 +473,8 @@ static int accept_from_sock(struct connection *con)
          * beween processing the accept adding the socket
          * to the read_sockets list
          */
-        if (!test_and_set_bit(CF_READ_PENDING, &newcon->flags))
-                queue_work(recv_workqueue, &newcon->rwork);
+        if (!test_and_set_bit(CF_READ_PENDING, &addcon->flags))
+                queue_work(recv_workqueue, &addcon->rwork);
         up_read(&con->sock_sem);
 
         return 0;
@@ -610,8 +614,7 @@ static struct socket *create_listen_sock(struct connection *con,
 
         result = sock->ops->listen(sock, 5);
         if (result < 0) {
-                printk("dlm: Can't listen on port %d\n",
-                       dlm_config.ci_tcp_port);
+                printk("dlm: Can't listen on port %d\n", dlm_config.ci_tcp_port);
                 sock_release(sock);
                 sock = NULL;
                 goto create_out;
@@ -811,7 +814,7 @@ send_error:
 
 out_connect:
         up_read(&con->sock_sem);
-        lowcomms_connect_sock(con);
+        connect_to_sock(con);
         return;
 }
 
@@ -873,9 +876,8 @@ static void process_send_sockets(struct work_struct *work)
                 connect_to_sock(con);
         }
 
-        if (test_and_clear_bit(CF_WRITE_PENDING, &con->flags)) {
-                send_to_sock(con);
-        }
+        clear_bit(CF_WRITE_PENDING, &con->flags);
+        send_to_sock(con);
 }