tap: add support for persistance
Type: feature
Change-Id: I775f53531972447ebae0d69b9e2dfeee84d115e5
Signed-off-by: Mohsin Kazmi <sykazmi@cisco.com>
diff --git a/src/vnet/devices/tap/FEATURE.yaml b/src/vnet/devices/tap/FEATURE.yaml
index ce2c510..a143d33 100644
--- a/src/vnet/devices/tap/FEATURE.yaml
+++ b/src/vnet/devices/tap/FEATURE.yaml
@@ -3,6 +3,8 @@
maintainer: damarion@cisco.com sluong@cisco.com sykazmi@cisco.com
features:
- Virtio
+ - persistence
+ - attach to existing tap at host
description: "Create a tap v2 device interface, which connects to a
tap interface on the host system."
missing:
diff --git a/src/vnet/devices/tap/cli.c b/src/vnet/devices/tap/cli.c
index 8d59210..68b8cef 100644
--- a/src/vnet/devices/tap/cli.c
+++ b/src/vnet/devices/tap/cli.c
@@ -92,6 +92,10 @@
args.tap_flags |= TAP_FLAG_GSO;
else if (unformat (line_input, "csum-offload"))
args.tap_flags |= TAP_FLAG_CSUM_OFFLOAD;
+ else if (unformat (line_input, "persist"))
+ args.tap_flags |= TAP_FLAG_PERSIST;
+ else if (unformat (line_input, "attach"))
+ args.tap_flags |= TAP_FLAG_ATTACH;
else if (unformat (line_input, "hw-addr %U",
unformat_ethernet_address, args.mac_addr.bytes))
args.mac_addr_set = 1;
@@ -131,7 +135,8 @@
"[host-bridge <bridge-name>] [host-ip4-addr <ip4addr/mask>] "
"[host-ip6-addr <ip6-addr>] [host-ip4-gw <ip4-addr>] "
"[host-ip6-gw <ip6-addr>] [host-mac-addr <host-mac-address>] "
- "[host-if-name <name>] [host-mtu-size <size>] [no-gso|gso|csum-offload]",
+ "[host-if-name <name>] [host-mtu-size <size>] [no-gso|gso|csum-offload] "
+ "[persist] [attach]",
.function = tap_create_command_fn,
};
/* *INDENT-ON* */
diff --git a/src/vnet/devices/tap/tap.c b/src/vnet/devices/tap/tap.c
index 6f16a4c..e17d01d 100644
--- a/src/vnet/devices/tap/tap.c
+++ b/src/vnet/devices/tap/tap.c
@@ -91,6 +91,7 @@
{
virtio_main_t *mm = &virtio_main;
tap_main_t *tm = &tap_main;
+ clib_error_t *err = 0;
int i;
/* *INDENT-OFF* */
@@ -102,6 +103,9 @@
virtio_vring_free_tx (vm, vif, TX_QUEUE (i));
/* *INDENT-ON* */
+ _IOCTL (vif->tap_fd, TUNSETPERSIST, (void *) (uintptr_t) 0);
+ tap_log_dbg (vif, "TUNSETPERSIST: unset");
+error:
if (vif->tap_fd != -1)
close (vif->tap_fd);
@@ -131,6 +135,7 @@
int i;
int old_netns_fd = -1;
struct ifreq ifr = {.ifr_flags = IFF_TAP | IFF_NO_PI | IFF_VNET_HDR };
+ struct ifreq get_ifr = {.ifr_flags = 0 };
size_t hdrsz;
struct vhost_memory *vhost_mem = 0;
virtio_if_t *vif = 0;
@@ -170,6 +175,39 @@
vif->num_rxqs = args->num_rx_queues;
num_q_pairs = clib_max (vif->num_rxqs, vif->num_txqs);
+ if (args->tap_flags & TAP_FLAG_ATTACH)
+ {
+ if (args->host_if_name != NULL)
+ {
+ host_if_name = (char *) args->host_if_name;
+ clib_memcpy (ifr.ifr_name, host_if_name,
+ clib_min (IFNAMSIZ, strlen (host_if_name)));
+ }
+ else
+ {
+ args->rv = VNET_API_ERROR_NO_MATCHING_INTERFACE;
+ err = clib_error_return (0, "host_if_name is not provided");
+ goto error;
+ }
+ if (args->host_namespace)
+ {
+ old_netns_fd = open ("/proc/self/ns/net", O_RDONLY);
+ if ((nfd = open_netns_fd ((char *) args->host_namespace)) == -1)
+ {
+ args->rv = VNET_API_ERROR_SYSCALL_ERROR_2;
+ args->error = clib_error_return_unix (0, "open_netns_fd '%s'",
+ args->host_namespace);
+ goto error;
+ }
+ if (setns (nfd, CLONE_NEWNET) == -1)
+ {
+ args->rv = VNET_API_ERROR_SYSCALL_ERROR_3;
+ args->error = clib_error_return_unix (0, "setns '%s'",
+ args->host_namespace);
+ goto error;
+ }
+ }
+ }
if ((vif->tap_fd = tfd = open ("/dev/net/tun", O_RDWR | O_NONBLOCK)) < 0)
{
args->rv = VNET_API_ERROR_SYSCALL_ERROR_2;
@@ -231,6 +269,33 @@
goto error;
}
+ /*
+ * unset the persistence when attaching to existing
+ * interface
+ */
+ if (args->tap_flags & TAP_FLAG_ATTACH)
+ {
+ _IOCTL (tfd, TUNSETPERSIST, (void *) (uintptr_t) 0);
+ tap_log_dbg (vif, "TUNSETPERSIST: unset");
+ }
+
+ /* set the persistence */
+ if (args->tap_flags & TAP_FLAG_PERSIST)
+ {
+ _IOCTL (tfd, TUNSETPERSIST, (void *) (uintptr_t) 1);
+ tap_log_dbg (vif, "TUNSETPERSIST: set");
+
+ /* verify persistence is set, read the flags */
+ _IOCTL (tfd, TUNGETIFF, (void *) &get_ifr);
+ tap_log_dbg (vif, "TUNGETIFF: flags 0x%lx", get_ifr.ifr_flags);
+ if ((get_ifr.ifr_flags & IFF_PERSIST) == 0)
+ {
+ args->rv = VNET_API_ERROR_SYSCALL_ERROR_2;
+ args->error = clib_error_return (0, "persistence not supported");
+ goto error;
+ }
+ }
+
tap_log_dbg (vif, "TUNSETVNETHDRSZ: fd %d vnet_hdr_sz %u", tfd, hdrsz);
_IOCTL (tfd, TUNSETVNETHDRSZ, &hdrsz);
@@ -291,46 +356,46 @@
virtio_set_net_hdr_size (vif);
- /* if namespace is specified, all further netlink messages should be executed
- after we change our net namespace */
- if (args->host_namespace)
+ if (!(args->tap_flags & TAP_FLAG_ATTACH))
{
- old_netns_fd = open ("/proc/self/ns/net", O_RDONLY);
- if ((nfd = open_netns_fd ((char *) args->host_namespace)) == -1)
+ /* if namespace is specified, all further netlink messages should be executed
+ after we change our net namespace */
+ if (args->host_namespace)
{
- args->rv = VNET_API_ERROR_SYSCALL_ERROR_2;
- args->error = clib_error_return_unix (0, "open_netns_fd '%s'",
- args->host_namespace);
- goto error;
- }
- args->error = vnet_netlink_set_link_netns (vif->ifindex, nfd,
- host_if_name);
- if (args->error)
- {
- args->rv = VNET_API_ERROR_NETLINK_ERROR;
- goto error;
- }
- if (setns (nfd, CLONE_NEWNET) == -1)
- {
- args->rv = VNET_API_ERROR_SYSCALL_ERROR_3;
- args->error = clib_error_return_unix (0, "setns '%s'",
- args->host_namespace);
- goto error;
- }
- if ((vif->ifindex = if_nametoindex (host_if_name)) == 0)
- {
- args->rv = VNET_API_ERROR_SYSCALL_ERROR_3;
- args->error = clib_error_return_unix (0, "if_nametoindex '%s'",
- host_if_name);
- goto error;
- }
- }
- else
- {
- if (host_if_name)
- {
- args->error = vnet_netlink_set_link_name (vif->ifindex,
+ old_netns_fd = open ("/proc/self/ns/net", O_RDONLY);
+ if ((nfd = open_netns_fd ((char *) args->host_namespace)) == -1)
+ {
+ args->rv = VNET_API_ERROR_SYSCALL_ERROR_2;
+ args->error = clib_error_return_unix (0, "open_netns_fd '%s'",
+ args->host_namespace);
+ goto error;
+ }
+ args->error = vnet_netlink_set_link_netns (vif->ifindex, nfd,
+ host_if_name);
+ if (args->error)
+ {
+ args->rv = VNET_API_ERROR_NETLINK_ERROR;
+ goto error;
+ }
+ if (setns (nfd, CLONE_NEWNET) == -1)
+ {
+ args->rv = VNET_API_ERROR_SYSCALL_ERROR_3;
+ args->error = clib_error_return_unix (0, "setns '%s'",
+ args->host_namespace);
+ goto error;
+ }
+ if ((vif->ifindex = if_nametoindex (host_if_name)) == 0)
+ {
+ args->rv = VNET_API_ERROR_SYSCALL_ERROR_3;
+ args->error = clib_error_return_unix (0, "if_nametoindex '%s'",
host_if_name);
+ goto error;
+ }
+ }
+ else if (host_if_name)
+ {
+ args->error =
+ vnet_netlink_set_link_name (vif->ifindex, host_if_name);
if (args->error)
{
args->rv = VNET_API_ERROR_NETLINK_ERROR;
diff --git a/src/vnet/devices/tap/tap.h b/src/vnet/devices/tap/tap.h
index fd4006b..5d087ad 100644
--- a/src/vnet/devices/tap/tap.h
+++ b/src/vnet/devices/tap/tap.h
@@ -33,6 +33,8 @@
u32 tap_flags;
#define TAP_FLAG_GSO (1 << 0)
#define TAP_FLAG_CSUM_OFFLOAD (1 << 1)
+#define TAP_FLAG_PERSIST (1 << 2)
+#define TAP_FLAG_ATTACH (1 << 3)
u8 *host_namespace;
u8 *host_if_name;
mac_address_t host_mac_addr;
diff --git a/src/vnet/devices/tap/tapv2.api b/src/vnet/devices/tap/tapv2.api
index 861fe17..ccbbe15 100644
--- a/src/vnet/devices/tap/tapv2.api
+++ b/src/vnet/devices/tap/tapv2.api
@@ -28,6 +28,8 @@
enum tap_flags {
TAP_FLAG_GSO = 1,
TAP_FLAG_CSUM_OFFLOAD = 2,
+ TAP_FLAG_PERSIST = 4,
+ TAP_FLAG_ATTACH = 8,
};
/** \brief Initialize a new tap interface with the given parameters
diff --git a/src/vnet/devices/tap/tapv2_api.c b/src/vnet/devices/tap/tapv2_api.c
index 3b66bf0..9e09459 100644
--- a/src/vnet/devices/tap/tapv2_api.c
+++ b/src/vnet/devices/tap/tapv2_api.c
@@ -164,8 +164,6 @@
rv = tap_delete_if (vm, sw_if_index);
-
-
rmp = vl_msg_api_alloc (sizeof (*rmp));
rmp->_vl_msg_id = ntohs (VL_API_TAP_DELETE_V2_REPLY);
rmp->context = mp->context;