netdev: Adopt four-step alloc/construct/destruct/dealloc lifecycle.

This is the same lifecycle used in the ofproto provider interface.
Compared to the previous netdev provider interface, it has the
advantage that the netdev top layer can control when any given
netdev becomes visible to the outside world.

Signed-off-by: Ben Pfaff <blp@nicira.com>

1 files changed, 80 insertions, 65 deletions

diff --git a/lib/netdev-linux.c b/lib/netdev-linux.c
index 93061006..cf459059 100644
--- a/lib/netdev-linux.c
+++ b/lib/netdev-linux.c
@@ -398,8 +398,6 @@ struct netdev_rx_linux {
     int fd;
 };
 
-static const struct netdev_rx_class netdev_rx_linux_class;
-
 /* This is set pretty low because we probably won't learn anything from the
  * additional log messages. */
 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 20);
@@ -448,7 +446,7 @@ netdev_linux_cast(const struct netdev *netdev)
 static struct netdev_rx_linux *
 netdev_rx_linux_cast(const struct netdev_rx *rx)
 {
-    netdev_rx_assert_class(rx, &netdev_rx_linux_class);
+    ovs_assert(is_netdev_linux_class(netdev_get_class(rx->netdev)));
     return CONTAINER_OF(rx, struct netdev_rx_linux, up);
 }
 
@@ -571,29 +569,38 @@ cache_notifier_unref(void)
     }
 }
 
+static struct netdev *
+netdev_linux_alloc(void)
+{
+    struct netdev_linux *netdev = xzalloc(sizeof *netdev);
+    return &netdev->up;
+}
+
+static int
+netdev_linux_common_construct(struct netdev_linux *netdev)
+{
+    netdev->change_seq = 1;
+
+    return cache_notifier_ref();
+}
+
 /* Creates system and internal devices. */
 static int
-netdev_linux_create(const struct netdev_class *class, const char *name,
-                    struct netdev **netdevp)
+netdev_linux_construct(struct netdev *netdev_)
 {
-    struct netdev_linux *netdev;
+    struct netdev_linux *netdev = netdev_linux_cast(netdev_);
     int error;
 
-    error = cache_notifier_ref();
+    error = netdev_linux_common_construct(netdev);
     if (error) {
         return error;
     }
 
-    netdev = xzalloc(sizeof *netdev);
-    netdev->change_seq = 1;
-    netdev_init(&netdev->up, name, class);
     error = get_flags(&netdev->up, &netdev->ifi_flags);
     if (error == ENODEV) {
-        if (class != &netdev_internal_class) {
+        if (netdev->up.netdev_class != &netdev_internal_class) {
             /* The device does not exist, so don't allow it to be opened. */
-            netdev_uninit(&netdev->up, false);
             cache_notifier_unref();
-            free(netdev);
             return ENODEV;
         } else {
             /* "Internal" netdevs have to be created as netdev objects before
@@ -603,7 +610,6 @@ netdev_linux_create(const struct netdev_class *class, const char *name,
         }
     }
 
-    *netdevp = &netdev->up;
     return 0;
 }
 
@@ -614,18 +620,15 @@ netdev_linux_create(const struct netdev_class *class, const char *name,
  * buffers, across all readers.  Therefore once data is read it will
  * be unavailable to other reads for tap devices. */
 static int
-netdev_linux_create_tap(const struct netdev_class *class OVS_UNUSED,
-                        const char *name, struct netdev **netdevp)
+netdev_linux_construct_tap(struct netdev *netdev_)
 {
-    struct netdev_linux *netdev;
+    struct netdev_linux *netdev = netdev_linux_cast(netdev_);
     static const char tap_dev[] = "/dev/net/tun";
+    const char *name = netdev_->name;
     struct ifreq ifr;
     int error;
 
-    netdev = xzalloc(sizeof *netdev);
-    netdev->change_seq = 1;
-
-    error = cache_notifier_ref();
+    error = netdev_linux_common_construct(netdev);
     if (error) {
         goto error;
     }
@@ -654,8 +657,6 @@ netdev_linux_create_tap(const struct netdev_class *class OVS_UNUSED,
         goto error_close;
     }
 
-    netdev_init(&netdev->up, name, &netdev_tap_class);
-    *netdevp = &netdev->up;
     return 0;
 
 error_close:
@@ -663,12 +664,11 @@ error_close:
 error_unref_notifier:
     cache_notifier_unref();
 error:
-    free(netdev);
     return error;
 }
 
 static void
-netdev_linux_destroy(struct netdev *netdev_)
+netdev_linux_destruct(struct netdev *netdev_)
 {
     struct netdev_linux *netdev = netdev_linux_cast(netdev_);
 
@@ -681,22 +681,35 @@ netdev_linux_destroy(struct netdev *netdev_)
     {
         close(netdev->tap_fd);
     }
-    free(netdev);
 
     cache_notifier_unref();
 }
 
+static void
+netdev_linux_dealloc(struct netdev *netdev_)
+{
+    struct netdev_linux *netdev = netdev_linux_cast(netdev_);
+    free(netdev);
+}
+
+static struct netdev_rx *
+netdev_linux_rx_alloc(void)
+{
+    struct netdev_rx_linux *rx = xzalloc(sizeof *rx);
+    return &rx->up;
+}
+
 static int
-netdev_linux_rx_open(struct netdev *netdev_, struct netdev_rx **rxp)
+netdev_linux_rx_construct(struct netdev_rx *rx_)
 {
+    struct netdev_rx_linux *rx = netdev_rx_linux_cast(rx_);
+    struct netdev *netdev_ = rx->up.netdev;
     struct netdev_linux *netdev = netdev_linux_cast(netdev_);
-    bool is_tap = is_tap_netdev(netdev_);
-    struct netdev_rx_linux *rx;
     int error;
-    int fd;
 
-    if (is_tap) {
-        fd = netdev->tap_fd;
+    rx->is_tap = is_tap_netdev(netdev_);
+    if (rx->is_tap) {
+        rx->fd = netdev->tap_fd;
     } else {
         struct sockaddr_ll sll;
         int ifindex;
@@ -712,15 +725,15 @@ netdev_linux_rx_open(struct netdev *netdev_, struct netdev_rx **rxp)
         };
 
         /* Create file descriptor. */
-        fd = socket(PF_PACKET, SOCK_RAW, 0);
-        if (fd < 0) {
+        rx->fd = socket(PF_PACKET, SOCK_RAW, 0);
+        if (rx->fd < 0) {
             error = errno;
             VLOG_ERR("failed to create raw socket (%s)", ovs_strerror(error));
             goto error;
         }
 
         /* Set non-blocking mode. */
-        error = set_nonblocking(fd);
+        error = set_nonblocking(rx->fd);
         if (error) {
             goto error;
         }
@@ -736,7 +749,7 @@ netdev_linux_rx_open(struct netdev *netdev_, struct netdev_rx **rxp)
         sll.sll_family = AF_PACKET;
         sll.sll_ifindex = ifindex;
         sll.sll_protocol = (OVS_FORCE unsigned short int) htons(ETH_P_ALL);
-        if (bind(fd, (struct sockaddr *) &sll, sizeof sll) < 0) {
+        if (bind(rx->fd, (struct sockaddr *) &sll, sizeof sll) < 0) {
             error = errno;
             VLOG_ERR("%s: failed to bind raw socket (%s)",
                      netdev_get_name(netdev_), ovs_strerror(error));
@@ -744,7 +757,7 @@ netdev_linux_rx_open(struct netdev *netdev_, struct netdev_rx **rxp)
         }
 
         /* Filter for only inbound packets. */
-        error = setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &fprog,
+        error = setsockopt(rx->fd, SOL_SOCKET, SO_ATTACH_FILTER, &fprog,
                            sizeof fprog);
         if (error) {
             error = errno;
@@ -754,34 +767,35 @@ netdev_linux_rx_open(struct netdev *netdev_, struct netdev_rx **rxp)
         }
     }
 
-    rx = xmalloc(sizeof *rx);
-    netdev_rx_init(&rx->up, netdev_, &netdev_rx_linux_class);
-    rx->is_tap = is_tap;
-    rx->fd = fd;
-
-    *rxp = &rx->up;
     return 0;
 
 error:
-    if (fd >= 0) {
-        close(fd);
+    if (rx->fd >= 0) {
+        close(rx->fd);
     }
     return error;
 }
 
 static void
-netdev_rx_linux_destroy(struct netdev_rx *rx_)
+netdev_linux_rx_destruct(struct netdev_rx *rx_)
 {
     struct netdev_rx_linux *rx = netdev_rx_linux_cast(rx_);
 
     if (!rx->is_tap) {
         close(rx->fd);
     }
+}
+
+static void
+netdev_linux_rx_dealloc(struct netdev_rx *rx_)
+{
+    struct netdev_rx_linux *rx = netdev_rx_linux_cast(rx_);
+
     free(rx);
 }
 
 static int
-netdev_rx_linux_recv(struct netdev_rx *rx_, void *data, size_t size)
+netdev_linux_rx_recv(struct netdev_rx *rx_, void *data, size_t size)
 {
     struct netdev_rx_linux *rx = netdev_rx_linux_cast(rx_);
     ssize_t retval;
@@ -804,14 +818,14 @@ netdev_rx_linux_recv(struct netdev_rx *rx_, void *data, size_t size)
 }
 
 static void
-netdev_rx_linux_wait(struct netdev_rx *rx_)
+netdev_linux_rx_wait(struct netdev_rx *rx_)
 {
     struct netdev_rx_linux *rx = netdev_rx_linux_cast(rx_);
     poll_fd_wait(rx->fd, POLLIN);
 }
 
 static int
-netdev_rx_linux_drain(struct netdev_rx *rx_)
+netdev_linux_rx_drain(struct netdev_rx *rx_)
 {
     struct netdev_rx_linux *rx = netdev_rx_linux_cast(rx_);
     if (rx->is_tap) {
@@ -2379,7 +2393,7 @@ netdev_linux_change_seq(const struct netdev *netdev)
     return netdev_linux_cast(netdev)->change_seq;
 }
 
-#define NETDEV_LINUX_CLASS(NAME, CREATE, GET_STATS, SET_STATS,  \
+#define NETDEV_LINUX_CLASS(NAME, CONSTRUCT, GET_STATS, SET_STATS,  \
                            GET_FEATURES, GET_STATUS)            \
 {                                                               \
     NAME,                                                       \
@@ -2388,14 +2402,14 @@ netdev_linux_change_seq(const struct netdev *netdev)
     netdev_linux_run,                                           \
     netdev_linux_wait,                                          \
                                                                 \
-    CREATE,                                                     \
-    netdev_linux_destroy,                                       \
+    netdev_linux_alloc,                                         \
+    CONSTRUCT,                                                  \
+    netdev_linux_destruct,                                      \
+    netdev_linux_dealloc,                                       \
     NULL,                       /* get_config */                \
     NULL,                       /* set_config */                \
     NULL,                       /* get_tunnel_config */         \
                                                                 \
-    netdev_linux_rx_open,                                       \
-                                                                \
     netdev_linux_send,                                          \
     netdev_linux_send_wait,                                     \
                                                                 \
@@ -2435,13 +2449,21 @@ netdev_linux_change_seq(const struct netdev *netdev)
                                                                 \
     netdev_linux_update_flags,                                  \
                                                                 \
-    netdev_linux_change_seq                                     \
+    netdev_linux_change_seq,                                    \
+                                                                \
+    netdev_linux_rx_alloc,                                      \
+    netdev_linux_rx_construct,                                  \
+    netdev_linux_rx_destruct,                                   \
+    netdev_linux_rx_dealloc,                                    \
+    netdev_linux_rx_recv,                                       \
+    netdev_linux_rx_wait,                                       \
+    netdev_linux_rx_drain,                                      \
 }
 
 const struct netdev_class netdev_linux_class =
     NETDEV_LINUX_CLASS(
         "system",
-        netdev_linux_create,
+        netdev_linux_construct,
         netdev_linux_get_stats,
         NULL,                    /* set_stats */
         netdev_linux_get_features,
@@ -2450,7 +2472,7 @@ const struct netdev_class netdev_linux_class =
 const struct netdev_class netdev_tap_class =
     NETDEV_LINUX_CLASS(
         "tap",
-        netdev_linux_create_tap,
+        netdev_linux_construct_tap,
         netdev_tap_get_stats,
         NULL,                   /* set_stats */
         netdev_linux_get_features,
@@ -2459,18 +2481,11 @@ const struct netdev_class netdev_tap_class =
 const struct netdev_class netdev_internal_class =
     NETDEV_LINUX_CLASS(
         "internal",
-        netdev_linux_create,
+        netdev_linux_construct,
         netdev_internal_get_stats,
         netdev_internal_set_stats,
         NULL,                  /* get_features */
         netdev_internal_get_status);
-
-static const struct netdev_rx_class netdev_rx_linux_class = {
-    netdev_rx_linux_destroy,
-    netdev_rx_linux_recv,
-    netdev_rx_linux_wait,
-    netdev_rx_linux_drain,
-};
 
 /* HTB traffic control class. */