diff options
Diffstat (limited to 'src/dpdk/drivers/net/virtio/virtio_user/vhost_kernel_tap.c')
| -rw-r--r-- | src/dpdk/drivers/net/virtio/virtio_user/vhost_kernel_tap.c | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/src/dpdk/drivers/net/virtio/virtio_user/vhost_kernel_tap.c b/src/dpdk/drivers/net/virtio/virtio_user/vhost_kernel_tap.c new file mode 100644 index 00000000..f585de8c --- /dev/null +++ b/src/dpdk/drivers/net/virtio/virtio_user/vhost_kernel_tap.c @@ -0,0 +1,133 @@ +/*- + * BSD LICENSE + * + * Copyright(c) 2016 Intel Corporation. All rights reserved. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include <unistd.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <net/if.h> +#include <errno.h> +#include <string.h> +#include <limits.h> + +#include "vhost_kernel_tap.h" +#include "../virtio_logs.h" + +int +vhost_kernel_open_tap(char **p_ifname, int hdr_size, int req_mq) +{ + unsigned int tap_features; + int sndbuf = INT_MAX; + struct ifreq ifr; + int tapfd; + unsigned int offload = + TUN_F_CSUM | + TUN_F_TSO4 | + TUN_F_TSO6 | + TUN_F_TSO_ECN | + TUN_F_UFO; + + /* TODO: + * 1. verify we can get/set vnet_hdr_len, tap_probe_vnet_hdr_len + * 2. get number of memory regions from vhost module parameter + * max_mem_regions, supported in newer version linux kernel + */ + tapfd = open(PATH_NET_TUN, O_RDWR); + if (tapfd < 0) { + PMD_DRV_LOG(ERR, "fail to open %s: %s", + PATH_NET_TUN, strerror(errno)); + return -1; + } + + /* Construct ifr */ + memset(&ifr, 0, sizeof(ifr)); + ifr.ifr_flags = IFF_TAP | IFF_NO_PI; + + if (ioctl(tapfd, TUNGETFEATURES, &tap_features) == -1) { + PMD_DRV_LOG(ERR, "TUNGETFEATURES failed: %s", strerror(errno)); + goto error; + } + if (tap_features & IFF_ONE_QUEUE) + ifr.ifr_flags |= IFF_ONE_QUEUE; + + /* Let tap instead of vhost-net handle vnet header, as the latter does + * not support offloading. And in this case, we should not set feature + * bit VHOST_NET_F_VIRTIO_NET_HDR. + */ + if (tap_features & IFF_VNET_HDR) { + ifr.ifr_flags |= IFF_VNET_HDR; + } else { + PMD_DRV_LOG(ERR, "TAP does not support IFF_VNET_HDR"); + goto error; + } + + if (req_mq) + ifr.ifr_flags |= IFF_MULTI_QUEUE; + + if (*p_ifname) + strncpy(ifr.ifr_name, *p_ifname, IFNAMSIZ); + else + strncpy(ifr.ifr_name, "tap%d", IFNAMSIZ); + if (ioctl(tapfd, TUNSETIFF, (void *)&ifr) == -1) { + PMD_DRV_LOG(ERR, "TUNSETIFF failed: %s", strerror(errno)); + goto error; + } + + fcntl(tapfd, F_SETFL, O_NONBLOCK); + + if (ioctl(tapfd, TUNSETVNETHDRSZ, &hdr_size) < 0) { + PMD_DRV_LOG(ERR, "TUNSETVNETHDRSZ failed: %s", strerror(errno)); + goto error; + } + + if (ioctl(tapfd, TUNSETSNDBUF, &sndbuf) < 0) { + PMD_DRV_LOG(ERR, "TUNSETSNDBUF failed: %s", strerror(errno)); + goto error; + } + + /* TODO: before set the offload capabilities, we'd better (1) check + * negotiated features to see if necessary to offload; (2) query tap + * to see if it supports the offload capabilities. + */ + if (ioctl(tapfd, TUNSETOFFLOAD, offload) != 0) + PMD_DRV_LOG(ERR, "TUNSETOFFLOAD ioctl() failed: %s", + strerror(errno)); + + if (!(*p_ifname)) + *p_ifname = strdup(ifr.ifr_name); + + return tapfd; +error: + close(tapfd); + return -1; +} |