libceph: fix socket write error handling
Sage Weil [Tue, 25 Jan 2011 16:19:34 +0000 (08:19 -0800)]
Pass errors from writing to the socket up the stack.  If we get -EAGAIN,
return 0 from the helper to simplify the callers' checks.

Signed-off-by: Sage Weil <sage@newdream.net>

net/ceph/messenger.c

index d95576d..35b36b8 100644 (file)
@@ -268,13 +268,17 @@ static int ceph_tcp_sendmsg(struct socket *sock, struct kvec *iov,
                     size_t kvlen, size_t len, int more)
 {
        struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL };
+       int r;
 
        if (more)
                msg.msg_flags |= MSG_MORE;
        else
                msg.msg_flags |= MSG_EOR;  /* superfluous, but what the hell */
 
-       return kernel_sendmsg(sock, &msg, iov, kvlen, len);
+       r = kernel_sendmsg(sock, &msg, iov, kvlen, len);
+       if (r == -EAGAIN)
+               r = 0;
+       return r;
 }
 
 
@@ -851,6 +855,8 @@ static int write_partial_msg_pages(struct ceph_connection *con)
                    (msg->pages || msg->pagelist || msg->bio || in_trail))
                        kunmap(page);
 
+               if (ret == -EAGAIN)
+                       ret = 0;
                if (ret <= 0)
                        goto out;
 
@@ -1741,16 +1747,12 @@ more_kvec:
        if (con->out_skip) {
                ret = write_partial_skip(con);
                if (ret <= 0)
-                       goto done;
-               if (ret < 0) {
-                       dout("try_write write_partial_skip err %d\n", ret);
-                       goto done;
-               }
+                       goto out;
        }
        if (con->out_kvec_left) {
                ret = write_partial_kvec(con);
                if (ret <= 0)
-                       goto done;
+                       goto out;
        }
 
        /* msg pages? */
@@ -1765,11 +1767,11 @@ more_kvec:
                if (ret == 1)
                        goto more_kvec;  /* we need to send the footer, too! */
                if (ret == 0)
-                       goto done;
+                       goto out;
                if (ret < 0) {
                        dout("try_write write_partial_msg_pages err %d\n",
                             ret);
-                       goto done;
+                       goto out;
                }
        }
 
@@ -1793,10 +1795,9 @@ do_next:
        /* Nothing to do! */
        clear_bit(WRITE_PENDING, &con->state);
        dout("try_write nothing else to write.\n");
-done:
        ret = 0;
 out:
-       dout("try_write done on %p\n", con);
+       dout("try_write done on %p ret %d\n", con, ret);
        return ret;
 }