ivshmem: use little-endian int64_t for the protocol

The current ivshmem protocol uses 'long' for integers. But the
sizeof(long) depends on the host and the endianess is not defined, which
may cause portability troubles.

Instead, switch to using little-endian int64_t. This breaks the
protocol, except on x64 little-endian host where this change
should be compatible.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Claudio Fontana <claudio.fontana@huawei.com>

diff --git a/contrib/ivshmem-client/ivshmem-client.c b/contrib/ivshmem-client/ivshmem-client.c
index 076e3ec31cbb2cf2bab7696f5025c5e75dfed4d6..31619d80e91b0052f7ea54b7cffcaab76ce7ad63 100644 (file)
--- a/contrib/ivshmem-client/ivshmem-client.c
+++ b/contrib/ivshmem-client/ivshmem-client.c
@@ -24,7 +24,7 @@
 
 /* read message from the unix socket */
 static int
-ivshmem_client_read_one_msg(IvshmemClient *client, long *index, int *fd)
+ivshmem_client_read_one_msg(IvshmemClient *client, int64_t *index, int *fd)
 {
     int ret;
     struct msghdr msg;
@@ -45,7 +45,7 @@ ivshmem_client_read_one_msg(IvshmemClient *client, long *index, int *fd)
     msg.msg_controllen = sizeof(msg_control);
 
     ret = recvmsg(client->sock_fd, &msg, 0);
-    if (ret < 0) {
+    if (ret < sizeof(*index)) {
         IVSHMEM_CLIENT_DEBUG(client, "cannot read message: %s\n",
                              strerror(errno));
         return -1;
@@ -55,6 +55,7 @@ ivshmem_client_read_one_msg(IvshmemClient *client, long *index, int *fd)
         return -1;
     }
 
+    *index = GINT64_FROM_LE(*index);
     *fd = -1;
 
     for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
@@ -91,7 +92,7 @@ static int
 ivshmem_client_handle_server_msg(IvshmemClient *client)
 {
     IvshmemClientPeer *peer;
-    long peer_id;
+    int64_t peer_id;
     int ret, fd;
 
     ret = ivshmem_client_read_one_msg(client, &peer_id, &fd);
@@ -107,11 +108,11 @@ ivshmem_client_handle_server_msg(IvshmemClient *client)
 
         if (peer == NULL || peer == &client->local) {
             IVSHMEM_CLIENT_DEBUG(client, "receive delete for invalid "
-                                 "peer %ld\n", peer_id);
+                                 "peer %" PRId64 "\n", peer_id);
             return -1;
         }
 
-        IVSHMEM_CLIENT_DEBUG(client, "delete peer id = %ld\n", peer_id);
+        IVSHMEM_CLIENT_DEBUG(client, "delete peer id = %" PRId64 "\n", peer_id);
         ivshmem_client_free_peer(client, peer);
         return 0;
     }
@@ -122,12 +123,12 @@ ivshmem_client_handle_server_msg(IvshmemClient *client)
         peer->id = peer_id;
         peer->vectors_count = 0;
         QTAILQ_INSERT_TAIL(&client->peer_list, peer, next);
-        IVSHMEM_CLIENT_DEBUG(client, "new peer id = %ld\n", peer_id);
+        IVSHMEM_CLIENT_DEBUG(client, "new peer id = %" PRId64 "\n", peer_id);
     }
 
     /* new vector */
-    IVSHMEM_CLIENT_DEBUG(client, "  new vector %d (fd=%d) for peer id %ld\n",
-                         peer->vectors_count, fd, peer->id);
+    IVSHMEM_CLIENT_DEBUG(client, "  new vector %d (fd=%d) for peer id %"
+                         PRId64 "\n", peer->vectors_count, fd, peer->id);
     if (peer->vectors_count >= G_N_ELEMENTS(peer->vectors)) {
         IVSHMEM_CLIENT_DEBUG(client, "Too many vectors received, failing");
         return -1;
@@ -180,7 +181,7 @@ ivshmem_client_connect(IvshmemClient *client)
 {
     struct sockaddr_un sun;
     int fd, ret;
-    long tmp;
+    int64_t tmp;
 
     IVSHMEM_CLIENT_DEBUG(client, "connect to client %s\n",
                          client->unix_sock_path);
@@ -219,7 +220,7 @@ ivshmem_client_connect(IvshmemClient *client)
         IVSHMEM_CLIENT_DEBUG(client, "cannot read from server (2)\n");
         goto err_close;
     }
-    IVSHMEM_CLIENT_DEBUG(client, "our_id=%ld\n", client->local.id);
+    IVSHMEM_CLIENT_DEBUG(client, "our_id=%" PRId64 "\n", client->local.id);
 
     /* now, we expect shared mem fd + a -1 index, note that shm fd
      * is not used */
@@ -350,13 +351,13 @@ ivshmem_client_notify(const IvshmemClient *client,
     int fd;
 
     if (vector >= peer->vectors_count) {
-        IVSHMEM_CLIENT_DEBUG(client, "invalid vector %u on peer %ld\n",
+        IVSHMEM_CLIENT_DEBUG(client, "invalid vector %u on peer %" PRId64 "\n",
                              vector, peer->id);
         return -1;
     }
     fd = peer->vectors[vector];
-    IVSHMEM_CLIENT_DEBUG(client, "notify peer %ld on vector %d, fd %d\n",
-                         peer->id, vector, fd);
+    IVSHMEM_CLIENT_DEBUG(client, "notify peer %" PRId64
+                         " on vector %d, fd %d\n", peer->id, vector, fd);
 
     kick = 1;
     if (write(fd, &kick, sizeof(kick)) != sizeof(kick)) {
@@ -402,7 +403,7 @@ ivshmem_client_notify_broadcast(const IvshmemClient *client)
 
 /* lookup peer from its id */
 IvshmemClientPeer *
-ivshmem_client_search_peer(IvshmemClient *client, long peer_id)
+ivshmem_client_search_peer(IvshmemClient *client, int64_t peer_id)
 {
     IvshmemClientPeer *peer;
 
@@ -427,7 +428,7 @@ ivshmem_client_dump(const IvshmemClient *client)
 
     /* dump local infos */
     peer = &client->local;
-    printf("our_id = %ld\n", peer->id);
+    printf("our_id = %" PRId64 "\n", peer->id);
     for (vector = 0; vector < peer->vectors_count; vector++) {
         printf("  vector %d is enabled (fd=%d)\n", vector,
                peer->vectors[vector]);
@@ -435,7 +436,7 @@ ivshmem_client_dump(const IvshmemClient *client)
 
     /* dump peers */
     QTAILQ_FOREACH(peer, &client->peer_list, next) {
-        printf("peer_id = %ld\n", peer->id);
+        printf("peer_id = %" PRId64 "\n", peer->id);
 
         for (vector = 0; vector < peer->vectors_count; vector++) {
             printf("  vector %d is enabled (fd=%d)\n", vector,

diff --git a/contrib/ivshmem-client/ivshmem-client.h b/contrib/ivshmem-client/ivshmem-client.h
index 9215f3420ee7c0d254eac181e06fb389f1d9f09a..3a4f8096827771a7c566180555825dd539cb0c6f 100644 (file)
--- a/contrib/ivshmem-client/ivshmem-client.h
+++ b/contrib/ivshmem-client/ivshmem-client.h
@@ -43,7 +43,7 @@
  */
 typedef struct IvshmemClientPeer {
     QTAILQ_ENTRY(IvshmemClientPeer) next;    /**< next in list*/
-    long id;                                 /**< the id of the peer */
+    int64_t id;                              /**< the id of the peer */
     int vectors[IVSHMEM_CLIENT_MAX_VECTORS]; /**< one fd per vector */
     unsigned vectors_count;                  /**< number of vectors */
 } IvshmemClientPeer;
@@ -198,7 +198,7 @@ int ivshmem_client_notify_broadcast(const IvshmemClient *client);
  * Returns:  The peer structure, or NULL if not found
  */
 IvshmemClientPeer *
-ivshmem_client_search_peer(IvshmemClient *client, long peer_id);
+ivshmem_client_search_peer(IvshmemClient *client, int64_t peer_id);
 
 /**
  * Dump information of this ivshmem client on stdout

diff --git a/contrib/ivshmem-client/main.c b/contrib/ivshmem-client/main.c
index 28dd81e5a189603b7dfc0a747ba5a203f2931429..c004870ae3362c411f4203b02539f803da69d867 100644 (file)
--- a/contrib/ivshmem-client/main.c
+++ b/contrib/ivshmem-client/main.c
@@ -179,7 +179,8 @@ ivshmem_client_notification_cb(const IvshmemClient *client,
 {
     (void)client;
     (void)arg;
-    printf("receive notification from peer_id=%ld vector=%d\n", peer->id, vect);
+    printf("receive notification from peer_id=%" PRId64 " vector=%u\n",
+           peer->id, vect);
 }
 
 int

diff --git a/contrib/ivshmem-server/ivshmem-server.c b/contrib/ivshmem-server/ivshmem-server.c
index e8693dec3cf715f3f47437fef5ad4be271e4a7e7..5e5239ce4547f6a79ad0cf1594b3092dc43adc38 100644 (file)
--- a/contrib/ivshmem-server/ivshmem-server.c
+++ b/contrib/ivshmem-server/ivshmem-server.c
@@ -33,7 +33,7 @@
 
 /* send message to a client unix socket */
 static int
-ivshmem_server_send_one_msg(int sock_fd, long peer_id, int fd)
+ivshmem_server_send_one_msg(int sock_fd, int64_t peer_id, int fd)
 {
     int ret;
     struct msghdr msg;
@@ -44,6 +44,7 @@ ivshmem_server_send_one_msg(int sock_fd, long peer_id, int fd)
     } msg_control;
     struct cmsghdr *cmsg;
 
+    peer_id = GINT64_TO_LE(peer_id);
     iov[0].iov_base = &peer_id;
     iov[0].iov_len = sizeof(peer_id);
 
@@ -79,7 +80,7 @@ ivshmem_server_free_peer(IvshmemServer *server, IvshmemServerPeer *peer)
     unsigned vector;
     IvshmemServerPeer *other_peer;
 
-    IVSHMEM_SERVER_DEBUG(server, "free peer %ld\n", peer->id);
+    IVSHMEM_SERVER_DEBUG(server, "free peer %" PRId64 "\n", peer->id);
     close(peer->sock_fd);
     QTAILQ_REMOVE(&server->peer_list, peer, next);
 
@@ -209,7 +210,7 @@ ivshmem_server_handle_new_conn(IvshmemServer *server)
     }
 
     QTAILQ_INSERT_TAIL(&server->peer_list, peer, next);
-    IVSHMEM_SERVER_DEBUG(server, "new peer id = %ld\n",
+    IVSHMEM_SERVER_DEBUG(server, "new peer id = %" PRId64 "\n",
                          peer->id);
     return 0;
 
@@ -459,7 +460,7 @@ ivshmem_server_handle_fds(IvshmemServer *server, fd_set *fds, int maxfd)
 
 /* lookup peer from its id */
 IvshmemServerPeer *
-ivshmem_server_search_peer(IvshmemServer *server, long peer_id)
+ivshmem_server_search_peer(IvshmemServer *server, int64_t peer_id)
 {
     IvshmemServerPeer *peer;
 
@@ -480,7 +481,7 @@ ivshmem_server_dump(const IvshmemServer *server)
 
     /* dump peers */
     QTAILQ_FOREACH(peer, &server->peer_list, next) {
-        printf("peer_id = %ld\n", peer->id);
+        printf("peer_id = %" PRId64 "\n", peer->id);
 
         for (vector = 0; vector < peer->vectors_count; vector++) {
             printf("  vector %d is enabled (fd=%d)\n", vector,

diff --git a/contrib/ivshmem-server/ivshmem-server.h b/contrib/ivshmem-server/ivshmem-server.h
index 89c905fa630b37a5434d3a66f1489f2af1036fb6..c9359a0a8a4ca8f6b4f83021bc90a69eef3e651a 100644 (file)
--- a/contrib/ivshmem-server/ivshmem-server.h
+++ b/contrib/ivshmem-server/ivshmem-server.h
@@ -51,7 +51,7 @@
 typedef struct IvshmemServerPeer {
     QTAILQ_ENTRY(IvshmemServerPeer) next;    /**< next in list*/
     int sock_fd;                             /**< connected unix sock */
-    long id;                                 /**< the id of the peer */
+    int64_t id;                              /**< the id of the peer */
     EventNotifier vectors[IVSHMEM_SERVER_MAX_VECTORS]; /**< one per vector */
     unsigned vectors_count;                  /**< number of vectors */
 } IvshmemServerPeer;
@@ -155,7 +155,7 @@ int ivshmem_server_handle_fds(IvshmemServer *server, fd_set *fds, int maxfd);
  * Returns:  The peer structure, or NULL if not found
  */
 IvshmemServerPeer *
-ivshmem_server_search_peer(IvshmemServer *server, long peer_id);
+ivshmem_server_search_peer(IvshmemServer *server, int64_t peer_id);
 
 /**
  * Dump information of this ivshmem server and its peers on stdout

diff --git a/docs/specs/ivshmem_device_spec.txt b/docs/specs/ivshmem_device_spec.txt
index 3435116b3708c8cb9301310b89eb801230030590..d318d65c3259fb0d2bf0721abdf924ec1d388d2c 100644 (file)
--- a/docs/specs/ivshmem_device_spec.txt
+++ b/docs/specs/ivshmem_device_spec.txt
@@ -61,7 +61,7 @@ This server code is available in qemu.git/contrib/ivshmem-server.
 
 The server must be started on the host before any guest.
 It creates a shared memory object then waits for clients to connect on a unix
-socket.
+socket. All the messages are little-endian int64_t integer.
 
 For each client (QEMU process) that connects to the server:
 - the server sends a protocol version, if client does not support it, the client

diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
index e9dae834da5abfc3ba143858fe53eb9617d75a53..83d7bd3e5f0d38d714ce2393b32eaca0a7da09f4 100644 (file)
--- a/hw/misc/ivshmem.c
+++ b/hw/misc/ivshmem.c
@@ -276,7 +276,7 @@ static void ivshmem_receive(void *opaque, const uint8_t *buf, int size)
 
 static int ivshmem_can_receive(void * opaque)
 {
-    return sizeof(long);
+    return sizeof(int64_t);
 }
 
 static void ivshmem_event(void *opaque, int event)
@@ -516,7 +516,7 @@ static bool fifo_update_and_get(IVShmemState *s, const uint8_t *buf, int size,
     const uint8_t *p;
     uint32_t num;
 
-    assert(len <= sizeof(long)); /* limitation of the fifo */
+    assert(len <= sizeof(int64_t)); /* limitation of the fifo */
     if (fifo8_is_empty(&s->incoming_fifo) && size == len) {
         memcpy(data, buf, size);
         return true;
@@ -524,7 +524,7 @@ static bool fifo_update_and_get(IVShmemState *s, const uint8_t *buf, int size,
 
     IVSHMEM_DPRINTF("short read of %d bytes\n", size);
 
-    num = MIN(size, sizeof(long) - fifo8_num_used(&s->incoming_fifo));
+    num = MIN(size, sizeof(int64_t) - fifo8_num_used(&s->incoming_fifo));
     fifo8_push_all(&s->incoming_fifo, buf, num);
 
     if (fifo8_num_used(&s->incoming_fifo) < len) {
@@ -546,6 +546,17 @@ static bool fifo_update_and_get(IVShmemState *s, const uint8_t *buf, int size,
     return true;
 }
 
+static bool fifo_update_and_get_i64(IVShmemState *s,
+                                    const uint8_t *buf, int size, int64_t *i64)
+{
+    if (fifo_update_and_get(s, buf, size, i64, sizeof(*i64))) {
+        *i64 = GINT64_FROM_LE(*i64);
+        return true;
+    }
+
+    return false;
+}
+
 static int ivshmem_add_kvm_msi_virq(IVShmemState *s, int vector)
 {
     PCIDevice *pdev = PCI_DEVICE(s);
@@ -603,23 +614,23 @@ static void ivshmem_read(void *opaque, const uint8_t *buf, int size)
     IVShmemState *s = opaque;
     int incoming_fd;
     int new_eventfd;
-    long incoming_posn;
+    int64_t incoming_posn;
     Error *err = NULL;
     Peer *peer;
 
-    if (!fifo_update_and_get(s, buf, size,
-                             &incoming_posn, sizeof(incoming_posn))) {
+    if (!fifo_update_and_get_i64(s, buf, size, &incoming_posn)) {
         return;
     }
 
     if (incoming_posn < -1) {
-        IVSHMEM_DPRINTF("invalid incoming_posn %ld\n", incoming_posn);
+        IVSHMEM_DPRINTF("invalid incoming_posn %" PRId64 "\n", incoming_posn);
         return;
     }
 
     /* pick off s->server_chr->msgfd and store it, posn should accompany msg */
     incoming_fd = qemu_chr_fe_get_msgfd(s->server_chr);
-    IVSHMEM_DPRINTF("posn is %ld, fd is %d\n", incoming_posn, incoming_fd);
+    IVSHMEM_DPRINTF("posn is %" PRId64 ", fd is %d\n",
+                    incoming_posn, incoming_fd);
 
     /* make sure we have enough space for this peer */
     if (incoming_posn >= s->nb_peers) {
@@ -641,7 +652,7 @@ static void ivshmem_read(void *opaque, const uint8_t *buf, int size)
             s->vm_id = incoming_posn;
         } else {
             /* otherwise an fd == -1 means an existing peer has gone away */
-            IVSHMEM_DPRINTF("posn %ld has gone away\n", incoming_posn);
+            IVSHMEM_DPRINTF("posn %" PRId64 " has gone away\n", incoming_posn);
             close_peer_eventfds(s, incoming_posn);
         }
         return;
@@ -697,7 +708,7 @@ static void ivshmem_read(void *opaque, const uint8_t *buf, int size)
     new_eventfd = peer->nb_eventfds++;
 
     /* this is an eventfd for a particular peer VM */
-    IVSHMEM_DPRINTF("eventfds[%ld][%d] = %d\n", incoming_posn,
+    IVSHMEM_DPRINTF("eventfds[%" PRId64 "][%d] = %d\n", incoming_posn,
                     new_eventfd, incoming_fd);
     event_notifier_init_fd(&peer->eventfds[new_eventfd], incoming_fd);
     fcntl_setfl(incoming_fd, O_NONBLOCK); /* msix/irqfd poll non block */
@@ -715,10 +726,9 @@ static void ivshmem_check_version(void *opaque, const uint8_t * buf, int size)
 {
     IVShmemState *s = opaque;
     int tmp;
-    long version;
+    int64_t version;
 
-    if (!fifo_update_and_get(s, buf, size,
-                             &version, sizeof(version))) {
+    if (!fifo_update_and_get_i64(s, buf, size, &version)) {
         return;
     }
 
@@ -873,7 +883,7 @@ static void pci_ivshmem_realize(PCIDevice *dev, Error **errp)
         s->ivshmem_size = size;
     }
 
-    fifo8_create(&s->incoming_fifo, sizeof(long));
+    fifo8_create(&s->incoming_fifo, sizeof(int64_t));
 
     /* IRQFD requires MSI */
     if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD) &&