net/tap: refactor ioctl calls

Create a socket for ioctl at tap device creation instead of opening it
and closing it every call to tap_link_set_flags().

Use a common tap_ioctl() function that can be extended for various uses
(such as MTU change, MAC address change, ...).

Signed-off-by: Pascal Mazon <pascal.mazon@6wind.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>

diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.c
index fcf4a1d..50a0724 100644 (file)
--- a/drivers/net/tap/rte_eth_tap.c
+++ b/drivers/net/tap/rte_eth_tap.c
@@ -114,6 +114,7 @@ struct pmd_internals {
        struct ether_addr eth_addr;     /* Mac address of the device port */
 
        int if_index;                   /* IF_INDEX for the port */
+       int ioctl_sock;                 /* socket for ioctl calls */
 
        struct rx_queue rxq[RTE_PMD_TAP_MAX_QUEUES];    /* List of RX queues */
        struct tx_queue txq[RTE_PMD_TAP_MAX_QUEUES];    /* List of TX queues */
@@ -328,63 +329,55 @@ pmd_tx_burst(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
 }
 
 static int
-tap_link_set_flags(struct pmd_internals *pmd, short flags, int add)
+tap_ioctl(struct pmd_internals *pmd, unsigned long request,
+         struct ifreq *ifr, int set)
 {
-       struct ifreq ifr;
-       int err, s;
-
-       /*
-        * An AF_INET/DGRAM socket is needed for
-        * SIOCGIFFLAGS/SIOCSIFFLAGS, using fd won't work.
-        */
-       s = socket(AF_INET, SOCK_DGRAM, 0);
-       if (s < 0) {
-               RTE_LOG(ERR, PMD,
-                       "Unable to get a socket to set flags: %s\n",
-                       strerror(errno));
-               return -1;
-       }
-       memset(&ifr, 0, sizeof(ifr));
-       snprintf(ifr.ifr_name, IFNAMSIZ, "%s", pmd->name);
-       err = ioctl(s, SIOCGIFFLAGS, &ifr);
-       if (err < 0) {
-               RTE_LOG(WARNING, PMD, "Unable to get %s device flags: %s\n",
-                       pmd->name, strerror(errno));
-               close(s);
-               return -1;
-       }
-       if (add)
-               ifr.ifr_flags |= flags;
-       else
-               ifr.ifr_flags &= ~flags;
-       err = ioctl(s, SIOCSIFFLAGS, &ifr);
-       if (err < 0) {
-               RTE_LOG(WARNING, PMD, "Unable to %s flags 0x%x: %s\n",
-                       add ? "set" : "unset", flags, strerror(errno));
-               close(s);
-               return -1;
-       }
-       close(s);
+       short req_flags = ifr->ifr_flags;
 
+       snprintf(ifr->ifr_name, IFNAMSIZ, "%s", pmd->name);
+       switch (request) {
+       case SIOCSIFFLAGS:
+               /* fetch current flags to leave other flags untouched */
+               if (ioctl(pmd->ioctl_sock, SIOCGIFFLAGS, ifr) < 0)
+                       goto error;
+               if (set)
+                       ifr->ifr_flags |= req_flags;
+               else
+                       ifr->ifr_flags &= ~req_flags;
+               break;
+       default:
+               RTE_LOG(WARNING, PMD, "%s: ioctl() called with wrong arg\n",
+                       pmd->name);
+               return -EINVAL;
+       }
+       if (ioctl(pmd->ioctl_sock, request, ifr) < 0)
+               goto error;
        return 0;
+
+error:
+       RTE_LOG(ERR, PMD, "%s: ioctl(%lu) failed with error: %s\n",
+               ifr->ifr_name, request, strerror(errno));
+       return -errno;
 }
 
 static int
 tap_link_set_down(struct rte_eth_dev *dev)
 {
        struct pmd_internals *pmd = dev->data->dev_private;
+       struct ifreq ifr = { .ifr_flags = IFF_UP };
 
        dev->data->dev_link.link_status = ETH_LINK_DOWN;
-       return tap_link_set_flags(pmd, IFF_UP, 0);
+       return tap_ioctl(pmd, SIOCSIFFLAGS, &ifr, 0);
 }
 
 static int
 tap_link_set_up(struct rte_eth_dev *dev)
 {
        struct pmd_internals *pmd = dev->data->dev_private;
+       struct ifreq ifr = { .ifr_flags = IFF_UP };
 
        dev->data->dev_link.link_status = ETH_LINK_UP;
-       return tap_link_set_flags(pmd, IFF_UP, 1);
+       return tap_ioctl(pmd, SIOCSIFFLAGS, &ifr, 1);
 }
 
 static int
@@ -518,36 +511,40 @@ static void
 tap_promisc_enable(struct rte_eth_dev *dev)
 {
        struct pmd_internals *pmd = dev->data->dev_private;
+       struct ifreq ifr = { .ifr_flags = IFF_PROMISC };
 
        dev->data->promiscuous = 1;
-       tap_link_set_flags(pmd, IFF_PROMISC, 1);
+       tap_ioctl(pmd, SIOCSIFFLAGS, &ifr, 1);
 }
 
 static void
 tap_promisc_disable(struct rte_eth_dev *dev)
 {
        struct pmd_internals *pmd = dev->data->dev_private;
+       struct ifreq ifr = { .ifr_flags = IFF_PROMISC };
 
        dev->data->promiscuous = 0;
-       tap_link_set_flags(pmd, IFF_PROMISC, 0);
+       tap_ioctl(pmd, SIOCSIFFLAGS, &ifr, 0);
 }
 
 static void
 tap_allmulti_enable(struct rte_eth_dev *dev)
 {
        struct pmd_internals *pmd = dev->data->dev_private;
+       struct ifreq ifr = { .ifr_flags = IFF_ALLMULTI };
 
        dev->data->all_multicast = 1;
-       tap_link_set_flags(pmd, IFF_ALLMULTI, 1);
+       tap_ioctl(pmd, SIOCSIFFLAGS, &ifr, 1);
 }
 
 static void
 tap_allmulti_disable(struct rte_eth_dev *dev)
 {
        struct pmd_internals *pmd = dev->data->dev_private;
+       struct ifreq ifr = { .ifr_flags = IFF_ALLMULTI };
 
        dev->data->all_multicast = 0;
-       tap_link_set_flags(pmd, IFF_ALLMULTI, 0);
+       tap_ioctl(pmd, SIOCSIFFLAGS, &ifr, 0);
 }
 
 static int
@@ -724,6 +721,14 @@ eth_dev_tap_create(const char *name, char *tap_name)
 
        pmd->nb_queues = RTE_PMD_TAP_MAX_QUEUES;
 
+       pmd->ioctl_sock = socket(AF_INET, SOCK_DGRAM, 0);
+       if (pmd->ioctl_sock == -1) {
+               RTE_LOG(ERR, PMD,
+                       "TAP Unable to get a socket for management: %s\n",
+                       strerror(errno));
+               goto error_exit;
+       }
+
        /* Setup some default values */
        data->dev_private = pmd;
        data->port_id = dev->data->port_id;
@@ -866,6 +871,7 @@ rte_pmd_tap_remove(const char *name)
                if (internals->rxq[i].fd != -1)
                        close(internals->rxq[i].fd);
 
+       close(internals->ioctl_sock);
        rte_free(eth_dev->data->dev_private);
        rte_free(eth_dev->data);