[Qemu-devel] [PATCH 5/6] virtio-9p-proxy: replace v9fs_receivefd with qemu_recv_with_fd

[Lei Li <lilei@linux.vnet.ibm.com>]

Signed-off-by: Lei Li <lilei@linux.vnet.ibm.com>
---
 hw/9pfs/virtio-9p-proxy.c |   60 ++------------------------------------------
 1 files changed, 3 insertions(+), 57 deletions(-)

diff --git a/hw/9pfs/virtio-9p-proxy.c b/hw/9pfs/virtio-9p-proxy.c
index 5f44bb7..f34b845 100644
--- a/hw/9pfs/virtio-9p-proxy.c
+++ b/hw/9pfs/virtio-9p-proxy.c
@@ -14,6 +14,7 @@
 #include "hw/virtio/virtio.h"
 #include "virtio-9p.h"
 #include "qemu/error-report.h"
+#include "qemu/fd-exchange.h"
 #include "fsdev/qemu-fsdev.h"
 #include "virtio-9p-proxy.h"
 
@@ -24,62 +25,6 @@ typedef struct V9fsProxy {
     struct iovec out_iovec;
 } V9fsProxy;
 
-/*
- * Return received file descriptor on success in *status.
- * errno is also returned on *status (which will be < 0)
- * return < 0 on transport error.
- */
-static int v9fs_receivefd(int sockfd, int *status)
-{
-    struct iovec iov;
-    struct msghdr msg;
-    struct cmsghdr *cmsg;
-    int retval, data, fd;
-    union MsgControl msg_control;
-
-    iov.iov_base = &data;
-    iov.iov_len = sizeof(data);
-
-    memset(&msg, 0, sizeof(msg));
-    msg.msg_iov = &iov;
-    msg.msg_iovlen = 1;
-    msg.msg_control = &msg_control;
-    msg.msg_controllen = sizeof(msg_control);
-
-    do {
-        retval = recvmsg(sockfd, &msg, 0);
-    } while (retval < 0 && errno == EINTR);
-    if (retval <= 0) {
-        return retval;
-    }
-    /*
-     * data is set to V9FS_FD_VALID, if ancillary data is sent.  If this
-     * request doesn't need ancillary data (fd) or an error occurred,
-     * data is set to negative errno value.
-     */
-    if (data != V9FS_FD_VALID) {
-        *status = data;
-        return 0;
-    }
-    /*
-     * File descriptor (fd) is sent in the ancillary data. Check if we
-     * indeed received it. One of the reasons to fail to receive it is if
-     * we exceeded the maximum number of file descriptors!
-     */
-    for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
-        if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)) ||
-            cmsg->cmsg_level != SOL_SOCKET ||
-            cmsg->cmsg_type != SCM_RIGHTS) {
-            continue;
-        }
-        fd = *((int *)CMSG_DATA(cmsg));
-        *status = fd;
-        return 0;
-    }
-    *status = -ENFILE;  /* Ancillary data sent but not received */
-    return 0;
-}
-
 static ssize_t socket_read(int sockfd, void *buff, size_t size)
 {
     ssize_t retval, total = 0;
@@ -307,6 +252,7 @@ static int v9fs_request(V9fsProxy *proxy, int type,
     V9fsString *name, *value;
     V9fsString *path, *oldpath;
     struct iovec *iovec = NULL, *reply = NULL;
+    int data = V9FS_FD_VALID;
 
     qemu_mutex_lock(&proxy->mutex);
 
@@ -548,7 +494,7 @@ static int v9fs_request(V9fsProxy *proxy, int type,
          * A file descriptor is returned as response for
          * T_OPEN,T_CREATE on success
          */
-        if (v9fs_receivefd(proxy->sockfd, &retval) < 0) {
+        if (qemu_recv_with_fd(proxy->sockfd, &retval, &data, sizeof(data)) < 0) {
             goto close_error;
         }
         break;
-- 
1.7.7.6