X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Fdpif-linux.c;h=5c2c755031d665246c84333cbc2ca36871dda94c;hb=856081f683d3e7d5b5fa07af4233d285eb205c47;hp=417349d8d768dfac6c44bcefcb93594d0d904bbe;hpb=e9e28be359f64c03944c0a282c17e714fcb0afc4;p=sliver-openvswitch.git

diff --git a/lib/dpif-linux.c b/lib/dpif-linux.c
index 417349d8d..5c2c75503 100644
--- a/lib/dpif-linux.c
+++ b/lib/dpif-linux.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2009 Nicira Networks.
+ * Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,32 +23,47 @@
 #include <fcntl.h>
 #include <inttypes.h>
 #include <net/if.h>
+#include <linux/types.h>
 #include <linux/ethtool.h>
+#include <linux/pkt_sched.h>
 #include <linux/rtnetlink.h>
 #include <linux/sockios.h>
 #include <stdlib.h>
 #include <sys/ioctl.h>
+#include <sys/stat.h>
 #include <unistd.h>
 
 #include "dpif-provider.h"
-#include "netdev-linux.h"
+#include "netdev.h"
+#include "netdev-vport.h"
+#include "netlink.h"
 #include "ofpbuf.h"
+#include "openvswitch/tunnel.h"
+#include "packets.h"
 #include "poll-loop.h"
+#include "rtnetlink.h"
+#include "rtnetlink-link.h"
+#include "shash.h"
 #include "svec.h"
 #include "util.h"
-
 #include "vlog.h"
-#define THIS_MODULE VLM_dpif_linux
+
+VLOG_DEFINE_THIS_MODULE(dpif_linux);
 
 /* Datapath interface for the openvswitch Linux kernel module. */
 struct dpif_linux {
     struct dpif dpif;
     int fd;
 
+    /* Used by dpif_linux_get_all_names(). */
+    char *local_ifname;
+    int minor;
+
     /* Change notification. */
     int local_ifindex;          /* Ifindex of local port. */
-    struct svec changed_ports;  /* Ports that have changed. */
-    struct linux_netdev_notifier port_notifier;
+    struct shash changed_ports;  /* Ports that have changed. */
+    struct rtnetlink_notifier port_notifier;
+    bool change_error;
 };
 
 static struct vlog_rate_limit error_rl = VLOG_RATE_LIMIT_INIT(9999, 5);
@@ -56,10 +71,11 @@ static struct vlog_rate_limit error_rl = VLOG_RATE_LIMIT_INIT(9999, 5);
 static int do_ioctl(const struct dpif *, int cmd, const void *arg);
 static int lookup_minor(const char *name, int *minor);
 static int finish_open(struct dpif *, const char *local_ifname);
+static int get_openvswitch_major(void);
 static int create_minor(const char *name, int minor, struct dpif **dpifp);
 static int open_minor(int minor, struct dpif **dpifp);
 static int make_openvswitch_device(int minor, char **fnp);
-static void dpif_linux_port_changed(const struct linux_netdev_change *,
+static void dpif_linux_port_changed(const struct rtnetlink_link_change *,
                                     void *dpif);
 
 static struct dpif_linux *
@@ -69,32 +85,52 @@ dpif_linux_cast(const struct dpif *dpif)
     return CONTAINER_OF(dpif, struct dpif_linux, dpif);
 }
 
-static void
-dpif_linux_run(void)
+static int
+dpif_linux_enumerate(struct svec *all_dps)
 {
-    linux_netdev_notifier_run();
-}
+    int major;
+    int error;
+    int i;
 
-static void
-dpif_linux_wait(void)
-{
-    linux_netdev_notifier_wait();
+    /* Check that the Open vSwitch module is loaded. */
+    major = get_openvswitch_major();
+    if (major < 0) {
+        return -major;
+    }
+
+    error = 0;
+    for (i = 0; i < ODP_MAX; i++) {
+        struct dpif *dpif;
+        char devname[16];
+        int retval;
+
+        sprintf(devname, "dp%d", i);
+        retval = dpif_open(devname, "system", &dpif);
+        if (!retval) {
+            svec_add(all_dps, devname);
+            dpif_uninit(dpif, true);
+        } else if (retval != ENODEV && !error) {
+            error = retval;
+        }
+    }
+    return error;
 }
 
 static int
-dpif_linux_open(const char *name UNUSED, char *suffix, bool create,
-                struct dpif **dpifp)
+dpif_linux_open(const struct dpif_class *class OVS_UNUSED, const char *name,
+                bool create, struct dpif **dpifp)
 {
     int minor;
 
-    minor = !strncmp(name, "dp", 2) && isdigit(name[2]) ? atoi(name + 2) : -1;
+    minor = !strncmp(name, "dp", 2)
+            && isdigit((unsigned char)name[2]) ? atoi(name + 2) : -1;
     if (create) {
         if (minor >= 0) {
-            return create_minor(suffix, minor, dpifp);
+            return create_minor(name, minor, dpifp);
         } else {
             /* Scan for unused minor number. */
             for (minor = 0; minor < ODP_MAX; minor++) {
-                int error = create_minor(suffix, minor, dpifp);
+                int error = create_minor(name, minor, dpifp);
                 if (error != EBUSY) {
                     return error;
                 }
@@ -109,7 +145,7 @@ dpif_linux_open(const char *name UNUSED, char *suffix, bool create,
         int error;
 
         if (minor < 0) {
-            error = lookup_minor(suffix, &minor);
+            error = lookup_minor(name, &minor);
             if (error) {
                 return error;
             }
@@ -125,13 +161,13 @@ dpif_linux_open(const char *name UNUSED, char *suffix, bool create,
          * getting the local port's name. */
         memset(&port, 0, sizeof port);
         port.port = ODPP_LOCAL;
-        if (ioctl(dpif->fd, ODP_PORT_QUERY, &port)) {
+        if (ioctl(dpif->fd, ODP_VPORT_QUERY, &port)) {
             error = errno;
             if (error != ENODEV) {
                 VLOG_WARN("%s: probe returned unexpected error: %s",
                           dpif_name(*dpifp), strerror(error));
             }
-            dpif_close(*dpifp);
+            dpif_uninit(*dpifp, true);
             return error;
         }
 
@@ -144,14 +180,25 @@ static void
 dpif_linux_close(struct dpif *dpif_)
 {
     struct dpif_linux *dpif = dpif_linux_cast(dpif_);
-    linux_netdev_notifier_unregister(&dpif->port_notifier);
-    svec_destroy(&dpif->changed_ports);
+    rtnetlink_link_notifier_unregister(&dpif->port_notifier);
+    shash_destroy(&dpif->changed_ports);
+    free(dpif->local_ifname);
     close(dpif->fd);
     free(dpif);
 }
 
 static int
-dpif_linux_delete(struct dpif *dpif_)
+dpif_linux_get_all_names(const struct dpif *dpif_, struct svec *all_names)
+{
+    struct dpif_linux *dpif = dpif_linux_cast(dpif_);
+
+    svec_add_nocopy(all_names, xasprintf("dp%d", dpif->minor));
+    svec_add(all_names, dpif->local_ifname);
+    return 0;
+}
+
+static int
+dpif_linux_destroy(struct dpif *dpif_)
 {
     return do_ioctl(dpif_, ODP_DP_DESTROY, NULL);
 }
@@ -159,6 +206,7 @@ dpif_linux_delete(struct dpif *dpif_)
 static int
 dpif_linux_get_stats(const struct dpif *dpif_, struct odp_stats *stats)
 {
+    memset(stats, 0, sizeof *stats);
     return do_ioctl(dpif_, ODP_DP_STATS, stats);
 }
 
@@ -182,46 +230,91 @@ dpif_linux_set_drop_frags(struct dpif *dpif_, bool drop_frags)
     return do_ioctl(dpif_, ODP_SET_DROP_FRAGS, &drop_frags_int);
 }
 
+static void
+translate_vport_type_to_netdev_type(struct odp_port *port)
+{
+    char *type = port->type;
+
+    if (!strcmp(type, "netdev")) {
+        ovs_strlcpy(type, "system", sizeof port->type);
+    } else if (!strcmp(type, "gre")) {
+        const struct tnl_port_config *config;
+
+        config = (struct tnl_port_config *)port->config;
+        if (config->flags & TNL_F_IPSEC) {
+            ovs_strlcpy(type, "ipsec_gre", sizeof port->type);
+        }
+    }
+}
+
+static void
+translate_netdev_type_to_vport_type(struct odp_port *port)
+{
+    char *type = port->type;
+
+    if (!strcmp(type, "system")) {
+        ovs_strlcpy(type, "netdev", sizeof port->type);
+    } else if (!strcmp(type, "ipsec_gre")) {
+        ovs_strlcpy(type, "gre", sizeof port->type);
+    }
+}
+
 static int
-dpif_linux_port_add(struct dpif *dpif_, const char *devname, uint16_t flags,
-                    uint16_t *port_no)
+dpif_linux_port_add(struct dpif *dpif, struct netdev *netdev,
+                    uint16_t *port_nop)
 {
+    const char *name = netdev_get_name(netdev);
+    const char *type = netdev_get_type(netdev);
     struct odp_port port;
     int error;
 
     memset(&port, 0, sizeof port);
-    strncpy(port.devname, devname, sizeof port.devname);
-    port.flags = flags;
-    error = do_ioctl(dpif_, ODP_PORT_ADD, &port);
+    strncpy(port.devname, name, sizeof port.devname);
+    strncpy(port.type, type, sizeof port.type);
+    netdev_vport_get_config(netdev, port.config);
+    translate_netdev_type_to_vport_type(&port);
+
+    error = do_ioctl(dpif, ODP_VPORT_ATTACH, &port);
     if (!error) {
-        *port_no = port.port;
+        *port_nop = port.port;
     }
+
     return error;
 }
 
 static int
-dpif_linux_port_del(struct dpif *dpif_, uint16_t port_no)
+dpif_linux_port_del(struct dpif *dpif_, uint16_t port_no_)
 {
-    int tmp = port_no;
-    return do_ioctl(dpif_, ODP_PORT_DEL, &tmp);
+    int port_no = port_no_;     /* Kernel expects an "int". */
+    return do_ioctl(dpif_, ODP_VPORT_DETACH, &port_no);
+}
+
+static int
+dpif_linux_port_query__(const struct dpif *dpif, struct odp_port *port)
+{
+    int error = do_ioctl(dpif, ODP_VPORT_QUERY, port);
+    if (!error) {
+        translate_vport_type_to_netdev_type(port);
+    }
+    return error;
 }
 
 static int
-dpif_linux_port_query_by_number(const struct dpif *dpif_, uint16_t port_no,
-                          struct odp_port *port)
+dpif_linux_port_query_by_number(const struct dpif *dpif, uint16_t port_no,
+                                struct odp_port *port)
 {
     memset(port, 0, sizeof *port);
     port->port = port_no;
-    return do_ioctl(dpif_, ODP_PORT_QUERY, port);
+    return dpif_linux_port_query__(dpif, port);
 }
 
 static int
-dpif_linux_port_query_by_name(const struct dpif *dpif_, const char *devname,
+dpif_linux_port_query_by_name(const struct dpif *dpif, const char *devname,
                               struct odp_port *port)
 {
     memset(port, 0, sizeof *port);
     strncpy(port->devname, devname, sizeof port->devname);
-    return do_ioctl(dpif_, ODP_PORT_QUERY, port);
+    return dpif_linux_port_query__(dpif, port);
 }
 
 static int
@@ -234,72 +327,53 @@ static int
 dpif_linux_port_list(const struct dpif *dpif_, struct odp_port *ports, int n)
 {
     struct odp_portvec pv;
+    unsigned int i;
     int error;
 
     pv.ports = ports;
     pv.n_ports = n;
-    error = do_ioctl(dpif_, ODP_PORT_LIST, &pv);
-    return error ? -error : pv.n_ports;
+    error = do_ioctl(dpif_, ODP_VPORT_LIST, &pv);
+    if (error) {
+        return -error;
+    }
+
+    for (i = 0; i < pv.n_ports; i++) {
+        struct odp_port *port = &pv.ports[i];
+
+        translate_vport_type_to_netdev_type(port);
+    }
+    return pv.n_ports;
 }
 
 static int
 dpif_linux_port_poll(const struct dpif *dpif_, char **devnamep)
 {
     struct dpif_linux *dpif = dpif_linux_cast(dpif_);
-    int error;
 
-    error = linux_netdev_notifier_get_error(&dpif->port_notifier);
-    if (!error) {
-        if (!dpif->changed_ports.n) {
-            return EAGAIN;
-        }
-        *devnamep = dpif->changed_ports.names[--dpif->changed_ports.n];
+    if (dpif->change_error) {
+        dpif->change_error = false;
+        shash_clear(&dpif->changed_ports);
+        return ENOBUFS;
+    } else if (!shash_is_empty(&dpif->changed_ports)) {
+        struct shash_node *node = shash_first(&dpif->changed_ports);
+        *devnamep = shash_steal(&dpif->changed_ports, node);
+        return 0;
     } else {
-        svec_clear(&dpif->changed_ports);
+        return EAGAIN;
     }
-    return error;
 }
 
 static void
 dpif_linux_port_poll_wait(const struct dpif *dpif_)
 {
     struct dpif_linux *dpif = dpif_linux_cast(dpif_);
-    if (dpif->changed_ports.n
-        || linux_netdev_notifier_peek_error(&dpif->port_notifier)) {
+    if (!shash_is_empty(&dpif->changed_ports) || dpif->change_error) {
         poll_immediate_wake();
     } else {
-        linux_netdev_notifier_wait();
+        rtnetlink_link_notifier_wait();
     }
 }
 
-static int
-dpif_linux_port_group_get(const struct dpif *dpif_, int group,
-                          uint16_t ports[], int n)
-{
-    struct odp_port_group pg;
-    int error;
-
-    assert(n <= UINT16_MAX);
-    pg.group = group;
-    pg.ports = ports;
-    pg.n_ports = n;
-    error = do_ioctl(dpif_, ODP_PORT_GROUP_GET, &pg);
-    return error ? -error : pg.n_ports;
-}
-
-static int
-dpif_linux_port_group_set(struct dpif *dpif_, int group,
-                          const uint16_t ports[], int n)
-{
-    struct odp_port_group pg;
-
-    assert(n <= UINT16_MAX);
-    pg.group = group;
-    pg.ports = (uint16_t *) ports;
-    pg.n_ports = n;
-    return do_ioctl(dpif_, ODP_PORT_GROUP_SET, &pg);
-}
-
 static int
 dpif_linux_flow_get(const struct dpif *dpif_, struct odp_flow flows[], int n)
 {
@@ -322,27 +396,40 @@ dpif_linux_flow_del(struct dpif *dpif_, struct odp_flow *flow)
 }
 
 static int
-dpif_linux_flow_list(const struct dpif *dpif_, struct odp_flow flows[], int n)
+dpif_linux_flow_dump_start(const struct dpif *dpif OVS_UNUSED, void **statep)
 {
-    struct odp_flowvec fv;
+    *statep = xzalloc(sizeof(struct odp_flow_dump));
+    return 0;
+}
+
+static int
+dpif_linux_flow_dump_next(const struct dpif *dpif, void *state,
+                          struct odp_flow *flow)
+{
+    struct odp_flow_dump *dump = state;
     int error;
 
-    fv.flows = flows;
-    fv.n_flows = n;
-    error = do_ioctl(dpif_, ODP_FLOW_LIST, &fv);
-    return error ? -error : fv.n_flows;
+    dump->flow = flow;
+    error = do_ioctl(dpif, ODP_FLOW_DUMP, dump);
+    return error ? error : flow->flags & ODPFF_EOF ? EOF : 0;
+}
+
+static int
+dpif_linux_flow_dump_done(const struct dpif *dpif OVS_UNUSED, void *state)
+{
+    free(state);
+    return 0;
 }
 
 static int
-dpif_linux_execute(struct dpif *dpif_, uint16_t in_port,
-                   const union odp_action actions[], int n_actions,
+dpif_linux_execute(struct dpif *dpif_,
+                   const struct nlattr *actions, size_t actions_len,
                    const struct ofpbuf *buf)
 {
     struct odp_execute execute;
     memset(&execute, 0, sizeof execute);
-    execute.in_port = in_port;
-    execute.actions = (union odp_action *) actions;
-    execute.n_actions = n_actions;
+    execute.actions = (struct nlattr *) actions;
+    execute.actions_len = actions_len;
     execute.data = buf->data;
     execute.length = buf->size;
     return do_ioctl(dpif_, ODP_EXECUTE, &execute);
@@ -361,7 +448,79 @@ dpif_linux_recv_set_mask(struct dpif *dpif_, int listen_mask)
 }
 
 static int
-dpif_linux_recv(struct dpif *dpif_, struct ofpbuf **bufp)
+dpif_linux_get_sflow_probability(const struct dpif *dpif_,
+                                 uint32_t *probability)
+{
+    return do_ioctl(dpif_, ODP_GET_SFLOW_PROBABILITY, probability);
+}
+
+static int
+dpif_linux_set_sflow_probability(struct dpif *dpif_, uint32_t probability)
+{
+    return do_ioctl(dpif_, ODP_SET_SFLOW_PROBABILITY, &probability);
+}
+
+static int
+dpif_linux_queue_to_priority(const struct dpif *dpif OVS_UNUSED,
+                             uint32_t queue_id, uint32_t *priority)
+{
+    if (queue_id < 0xf000) {
+        *priority = TC_H_MAKE(1 << 16, queue_id + 1);
+        return 0;
+    } else {
+        return EINVAL;
+    }
+}
+
+static int
+parse_odp_packet(struct ofpbuf *buf, struct dpif_upcall *upcall)
+{
+    static const struct nl_policy odp_packet_policy[] = {
+        /* Always present. */
+        [ODP_PACKET_ATTR_TYPE] = { .type = NL_A_U32 },
+        [ODP_PACKET_ATTR_PACKET] = { .type = NL_A_UNSPEC,
+                                     .min_len = ETH_HEADER_LEN },
+        [ODP_PACKET_ATTR_KEY] = { .type = NL_A_NESTED },
+
+        /* _ODPL_ACTION_NR only. */
+        [ODP_PACKET_ATTR_USERDATA] = { .type = NL_A_U64, .optional = true },
+
+        /* _ODPL_SFLOW_NR only. */
+        [ODP_PACKET_ATTR_SAMPLE_POOL] = { .type = NL_A_U32, .optional = true },
+        [ODP_PACKET_ATTR_ACTIONS] = { .type = NL_A_NESTED, .optional = true },
+    };
+
+    struct odp_packet *odp_packet = buf->data;
+    struct nlattr *a[ARRAY_SIZE(odp_packet_policy)];
+
+    if (!nl_policy_parse(buf, sizeof *odp_packet, odp_packet_policy,
+                         a, ARRAY_SIZE(odp_packet_policy))) {
+        return EINVAL;
+    }
+
+    memset(upcall, 0, sizeof *upcall);
+    upcall->type = nl_attr_get_u32(a[ODP_PACKET_ATTR_TYPE]);
+    upcall->packet = buf;
+    upcall->packet->data = (void *) nl_attr_get(a[ODP_PACKET_ATTR_PACKET]);
+    upcall->packet->size = nl_attr_get_size(a[ODP_PACKET_ATTR_PACKET]);
+    upcall->key = (void *) nl_attr_get(a[ODP_PACKET_ATTR_KEY]);
+    upcall->key_len = nl_attr_get_size(a[ODP_PACKET_ATTR_KEY]);
+    upcall->userdata = (a[ODP_PACKET_ATTR_USERDATA]
+                        ? nl_attr_get_u64(a[ODP_PACKET_ATTR_USERDATA])
+                        : 0);
+    upcall->sample_pool = (a[ODP_PACKET_ATTR_SAMPLE_POOL]
+                        ? nl_attr_get_u32(a[ODP_PACKET_ATTR_SAMPLE_POOL])
+                           : 0);
+    if (a[ODP_PACKET_ATTR_ACTIONS]) {
+        upcall->actions = (void *) nl_attr_get(a[ODP_PACKET_ATTR_ACTIONS]);
+        upcall->actions_len = nl_attr_get_size(a[ODP_PACKET_ATTR_ACTIONS]);
+    }
+
+    return 0;
+}
+
+static int
+dpif_linux_recv(struct dpif *dpif_, struct dpif_upcall *upcall)
 {
     struct dpif_linux *dpif = dpif_linux_cast(dpif_);
     struct ofpbuf *buf;
@@ -376,30 +535,30 @@ dpif_linux_recv(struct dpif *dpif_, struct ofpbuf **bufp)
             VLOG_WARN_RL(&error_rl, "%s: read failed: %s",
                          dpif_name(dpif_), strerror(error));
         }
-    } else if (retval >= sizeof(struct odp_msg)) {
-        struct odp_msg *msg = buf->data;
-        if (msg->length <= retval) {
-            buf->size += retval;
-            *bufp = buf;
-            return 0;
+    } else if (retval >= sizeof(struct odp_packet)) {
+        struct odp_packet *odp_packet = buf->data;
+        buf->size += retval;
+
+        if (odp_packet->len <= retval) {
+            error = parse_odp_packet(buf, upcall);
         } else {
             VLOG_WARN_RL(&error_rl, "%s: discarding message truncated "
-                         "from %zu bytes to %d",
-                         dpif_name(dpif_), msg->length, retval);
+                         "from %"PRIu32" bytes to %d",
+                         dpif_name(dpif_), odp_packet->len, retval);
             error = ERANGE;
         }
     } else if (!retval) {
         VLOG_WARN_RL(&error_rl, "%s: unexpected end of file", dpif_name(dpif_));
         error = EPROTO;
     } else {
-        VLOG_WARN_RL(&error_rl,
-                     "%s: discarding too-short message (%d bytes)",
+        VLOG_WARN_RL(&error_rl, "%s: discarding too-short message (%d bytes)",
                      dpif_name(dpif_), retval);
         error = ERANGE;
     }
 
-    *bufp = NULL;
-    ofpbuf_delete(buf);
+    if (error) {
+        ofpbuf_delete(buf);
+    }
     return error;
 }
 
@@ -411,13 +570,14 @@ dpif_linux_recv_wait(struct dpif *dpif_)
 }
 
 const struct dpif_class dpif_linux_class = {
-    "",                         /* This is the default class. */
-    "linux",
-    dpif_linux_run,
-    dpif_linux_wait,
+    "system",
+    NULL,
+    NULL,
+    dpif_linux_enumerate,
     dpif_linux_open,
     dpif_linux_close,
-    dpif_linux_delete,
+    dpif_linux_get_all_names,
+    dpif_linux_destroy,
     dpif_linux_get_stats,
     dpif_linux_get_drop_frags,
     dpif_linux_set_drop_frags,
@@ -428,22 +588,25 @@ const struct dpif_class dpif_linux_class = {
     dpif_linux_port_list,
     dpif_linux_port_poll,
     dpif_linux_port_poll_wait,
-    dpif_linux_port_group_get,
-    dpif_linux_port_group_set,
     dpif_linux_flow_get,
     dpif_linux_flow_put,
     dpif_linux_flow_del,
     dpif_linux_flow_flush,
-    dpif_linux_flow_list,
+    dpif_linux_flow_dump_start,
+    dpif_linux_flow_dump_next,
+    dpif_linux_flow_dump_done,
     dpif_linux_execute,
     dpif_linux_recv_get_mask,
     dpif_linux_recv_set_mask,
+    dpif_linux_get_sflow_probability,
+    dpif_linux_set_sflow_probability,
+    dpif_linux_queue_to_priority,
     dpif_linux_recv,
     dpif_linux_recv_wait,
 };
 
 static int get_openvswitch_major(void);
-static int get_major(const char *target, int default_major);
+static int get_major(const char *target);
 
 static int
 do_ioctl(const struct dpif *dpif_, int cmd, const void *arg)
@@ -453,9 +616,10 @@ do_ioctl(const struct dpif *dpif_, int cmd, const void *arg)
 }
 
 static int
-lookup_minor(const char *name, int *minor)
+lookup_minor(const char *name, int *minorp)
 {
     struct ethtool_drvinfo drvinfo;
+    int minor, port_no;
     struct ifreq ifr;
     int error;
     int sock;
@@ -485,14 +649,20 @@ lookup_minor(const char *name, int *minor)
         goto error_close_sock;
     }
 
-    if (!isdigit(drvinfo.bus_info[0])) {
-        VLOG_WARN("%s ethtool info does not contain an openvswitch minor",
-                  name);
+    if (sscanf(drvinfo.bus_info, "%d.%d", &minor, &port_no) != 2) {
+        VLOG_WARN("%s ethtool bus_info has unexpected format", name);
         error = EPROTOTYPE;
         goto error_close_sock;
+    } else if (port_no != ODPP_LOCAL) {
+        /* This is an Open vSwitch device but not the local port.  We
+         * intentionally support only using the name of the local port as the
+         * name of a datapath; otherwise, it would be too difficult to
+         * enumerate all the names of a datapath. */
+        error = EOPNOTSUPP;
+        goto error_close_sock;
     }
 
-    *minor = atoi(drvinfo.bus_info);
+    *minorp = minor;
     close(sock);
     return 0;
 
@@ -505,12 +675,20 @@ error:
 static int
 make_openvswitch_device(int minor, char **fnp)
 {
-    dev_t dev = makedev(get_openvswitch_major(), minor);
     const char dirname[] = "/dev/net";
+    int major;
+    dev_t dev;
     struct stat s;
     char fn[128];
 
     *fnp = NULL;
+
+    major = get_openvswitch_major();
+    if (major < 0) {
+        return -major;
+    }
+    dev = makedev(major, minor);
+
     sprintf(fn, "%s/dp%d", dirname, minor);
     if (!stat(fn, &s)) {
         if (!S_ISCHR(s.st_mode)) {
@@ -518,7 +696,7 @@ make_openvswitch_device(int minor, char **fnp)
                          fn);
         } else if (s.st_rdev != dev) {
             VLOG_WARN_RL(&error_rl,
-                         "%s is device %u:%u instead of %u:%u, fixing",
+                         "%s is device %u:%u but should be %u:%u, fixing",
                          fn, major(s.st_rdev), minor(s.st_rdev),
                          major(dev), minor(dev));
         } else {
@@ -561,20 +739,20 @@ success:
     return 0;
 }
 
-
+/* Return the major device number of the Open vSwitch device.  If it
+ * cannot be determined, a negative errno is returned. */
 static int
 get_openvswitch_major(void)
 {
-    static unsigned int openvswitch_major;
-    if (!openvswitch_major) {
-        enum { DEFAULT_MAJOR = 248 };
-        openvswitch_major = get_major("openvswitch", DEFAULT_MAJOR);
+    static int openvswitch_major = -1;
+    if (openvswitch_major < 0) {
+        openvswitch_major = get_major("openvswitch");
     }
     return openvswitch_major;
 }
 
 static int
-get_major(const char *target, int default_major)
+get_major(const char *target)
 {
     const char fn[] = "/proc/devices";
     char line[128];
@@ -584,7 +762,7 @@ get_major(const char *target, int default_major)
     file = fopen(fn, "r");
     if (!file) {
         VLOG_ERR("opening %s failed (%s)", fn, strerror(errno));
-        goto error;
+        return -errno;
     }
 
     for (ln = 1; fgets(line, sizeof line, file); ln++) {
@@ -602,29 +780,25 @@ get_major(const char *target, int default_major)
                 return major;
             }
         } else {
-            static bool warned;
-            if (!warned) {
-                VLOG_WARN("%s:%d: syntax error", fn, ln);
-            }
-            warned = true;
+            VLOG_WARN_ONCE("%s:%d: syntax error", fn, ln);
         }
     }
 
-    VLOG_ERR("%s: %s major not found (is the module loaded?), using "
-             "default major %d", fn, target, default_major);
-error:
-    VLOG_INFO("using default major %d for %s", default_major, target);
-    return default_major;
+    fclose(file);
+
+    VLOG_ERR("%s: %s major not found (is the module loaded?)", fn, target);
+    return -ENODEV;
 }
 
 static int
 finish_open(struct dpif *dpif_, const char *local_ifname)
 {
     struct dpif_linux *dpif = dpif_linux_cast(dpif_);
+    dpif->local_ifname = xstrdup(local_ifname);
     dpif->local_ifindex = if_nametoindex(local_ifname);
     if (!dpif->local_ifindex) {
         int error = errno;
-        dpif_close(dpif_);
+        dpif_uninit(dpif_, true);
         VLOG_WARN("could not get ifindex of %s device: %s",
                   local_ifname, strerror(errno));
         return error;
@@ -641,7 +815,7 @@ create_minor(const char *name, int minor, struct dpif **dpifp)
         if (!error) {
             error = finish_open(*dpifp, name);
         } else {
-            dpif_close(*dpifp);
+            dpif_uninit(*dpifp, true);
         }
     }
     return error;
@@ -662,8 +836,9 @@ open_minor(int minor, struct dpif **dpifp)
     fd = open(fn, O_RDONLY | O_NONBLOCK);
     if (fd >= 0) {
         struct dpif_linux *dpif = xmalloc(sizeof *dpif);
-        error = linux_netdev_notifier_register(&dpif->port_notifier,
-                                               dpif_linux_port_changed, dpif);
+        error = rtnetlink_link_notifier_register(&dpif->port_notifier,
+                                                 dpif_linux_port_changed,
+                                                 dpif);
         if (!error) {
             char *name;
 
@@ -672,8 +847,11 @@ open_minor(int minor, struct dpif **dpifp)
             free(name);
 
             dpif->fd = fd;
+            dpif->local_ifname = NULL;
+            dpif->minor = minor;
             dpif->local_ifindex = 0;
-            svec_init(&dpif->changed_ports);
+            shash_init(&dpif->changed_ports);
+            dpif->change_error = false;
             *dpifp = &dpif->dpif;
         } else {
             free(dpif);
@@ -688,19 +866,21 @@ open_minor(int minor, struct dpif **dpifp)
 }
 
 static void
-dpif_linux_port_changed(const struct linux_netdev_change *change, void *dpif_)
+dpif_linux_port_changed(const struct rtnetlink_link_change *change,
+                        void *dpif_)
 {
     struct dpif_linux *dpif = dpif_;
 
-    if (change->master_ifindex == dpif->local_ifindex
-        && (change->nlmsg_type == RTM_NEWLINK
-            || change->nlmsg_type == RTM_DELLINK))
-    {
-        /* Our datapath changed, either adding a new port or deleting an
-         * existing one. */
-        if (!svec_contains(&dpif->changed_ports, change->ifname)) {
-            svec_add(&dpif->changed_ports, change->ifname);
-            svec_sort(&dpif->changed_ports);
+    if (change) {
+        if (change->master_ifindex == dpif->local_ifindex
+            && (change->nlmsg_type == RTM_NEWLINK
+                || change->nlmsg_type == RTM_DELLINK))
+        {
+            /* Our datapath changed, either adding a new port or deleting an
+             * existing one. */
+            shash_add_once(&dpif->changed_ports, change->ifname, NULL);
         }
+    } else {
+        dpif->change_error = true;
     }
 }