diff options
Diffstat (limited to 'src/vnet/devices/af_packet/device.c')
| -rw-r--r-- | src/vnet/devices/af_packet/device.c | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/src/vnet/devices/af_packet/device.c b/src/vnet/devices/af_packet/device.c new file mode 100644 index 00000000000..1fb4000f6e6 --- /dev/null +++ b/src/vnet/devices/af_packet/device.c @@ -0,0 +1,250 @@ +/* + *------------------------------------------------------------------ + * af_packet.c - linux kernel packet interface + * + * Copyright (c) 2016 Cisco and/or its affiliates. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + *------------------------------------------------------------------ + */ + +#include <linux/if_packet.h> + +#include <vlib/vlib.h> +#include <vlib/unix/unix.h> +#include <vnet/ip/ip.h> +#include <vnet/ethernet/ethernet.h> + +#include <vnet/devices/af_packet/af_packet.h> + +#define foreach_af_packet_tx_func_error \ +_(FRAME_NOT_READY, "tx frame not ready") \ +_(TXRING_EAGAIN, "tx sendto temporary failure") \ +_(TXRING_FATAL, "tx sendto fatal failure") \ +_(TXRING_OVERRUN, "tx ring overrun") + +typedef enum +{ +#define _(f,s) AF_PACKET_TX_ERROR_##f, + foreach_af_packet_tx_func_error +#undef _ + AF_PACKET_TX_N_ERROR, +} af_packet_tx_func_error_t; + +static char *af_packet_tx_func_error_strings[] = { +#define _(n,s) s, + foreach_af_packet_tx_func_error +#undef _ +}; + + +static u8 * +format_af_packet_device_name (u8 * s, va_list * args) +{ + u32 i = va_arg (*args, u32); + af_packet_main_t *apm = &af_packet_main; + af_packet_if_t *apif = pool_elt_at_index (apm->interfaces, i); + + s = format (s, "host-%s", apif->host_if_name); + return s; +} + +static u8 * +format_af_packet_device (u8 * s, va_list * args) +{ + s = format (s, "Linux PACKET socket interface"); + return s; +} + +static u8 * +format_af_packet_tx_trace (u8 * s, va_list * args) +{ + s = format (s, "Unimplemented..."); + return s; +} + +static uword +af_packet_interface_tx (vlib_main_t * vm, + vlib_node_runtime_t * node, vlib_frame_t * frame) +{ + af_packet_main_t *apm = &af_packet_main; + u32 *buffers = vlib_frame_args (frame); + u32 n_left = frame->n_vectors; + u32 n_sent = 0; + vnet_interface_output_runtime_t *rd = (void *) node->runtime_data; + af_packet_if_t *apif = + pool_elt_at_index (apm->interfaces, rd->dev_instance); + int block = 0; + u32 block_size = apif->tx_req->tp_block_size; + u32 frame_size = apif->tx_req->tp_frame_size; + u32 frame_num = apif->tx_req->tp_frame_nr; + u8 *block_start = apif->tx_ring + block * block_size; + u32 tx_frame = apif->next_tx_frame; + struct tpacket2_hdr *tph; + u32 frame_not_ready = 0; + + while (n_left > 0) + { + u32 len; + u32 offset = 0; + vlib_buffer_t *b0; + n_left--; + u32 bi = buffers[0]; + buffers++; + + tph = (struct tpacket2_hdr *) (block_start + tx_frame * frame_size); + + if (PREDICT_FALSE + (tph->tp_status & (TP_STATUS_SEND_REQUEST | TP_STATUS_SENDING))) + { + frame_not_ready++; + goto next; + } + + do + { + b0 = vlib_get_buffer (vm, bi); + len = b0->current_length; + clib_memcpy ((u8 *) tph + + TPACKET_ALIGN (sizeof (struct tpacket2_hdr)) + offset, + vlib_buffer_get_current (b0), len); + offset += len; + } + while ((bi = b0->next_buffer)); + + tph->tp_len = tph->tp_snaplen = offset; + tph->tp_status = TP_STATUS_SEND_REQUEST; + n_sent++; + next: + /* check if we've exhausted the ring */ + if (PREDICT_FALSE (frame_not_ready + n_sent == frame_num)) + break; + + tx_frame = (tx_frame + 1) % frame_num; + } + + CLIB_MEMORY_BARRIER (); + + if (PREDICT_TRUE (n_sent)) + { + apif->next_tx_frame = tx_frame; + + if (PREDICT_FALSE (sendto (apif->fd, NULL, 0, + MSG_DONTWAIT, NULL, 0) == -1)) + { + /* Uh-oh, drop & move on, but count whether it was fatal or not. + * Note that we have no reliable way to properly determine the + * disposition of the packets we just enqueued for delivery. + */ + vlib_error_count (vm, node->node_index, + unix_error_is_fatal (errno) ? + AF_PACKET_TX_ERROR_TXRING_FATAL : + AF_PACKET_TX_ERROR_TXRING_EAGAIN, n_sent); + } + } + + if (PREDICT_FALSE (frame_not_ready)) + vlib_error_count (vm, node->node_index, + AF_PACKET_TX_ERROR_FRAME_NOT_READY, frame_not_ready); + + if (PREDICT_FALSE (frame_not_ready + n_sent == frame_num)) + vlib_error_count (vm, node->node_index, AF_PACKET_TX_ERROR_TXRING_OVERRUN, + n_left); + + vlib_buffer_free (vm, vlib_frame_args (frame), frame->n_vectors); + return frame->n_vectors; +} + +static void +af_packet_set_interface_next_node (vnet_main_t * vnm, u32 hw_if_index, + u32 node_index) +{ + af_packet_main_t *apm = &af_packet_main; + vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index); + af_packet_if_t *apif = + pool_elt_at_index (apm->interfaces, hw->dev_instance); + + /* Shut off redirection */ + if (node_index == ~0) + { + apif->per_interface_next_index = node_index; + return; + } + + apif->per_interface_next_index = + vlib_node_add_next (vlib_get_main (), af_packet_input_node.index, + node_index); +} + +static void +af_packet_clear_hw_interface_counters (u32 instance) +{ + /* Nothing for now */ +} + +static clib_error_t * +af_packet_interface_admin_up_down (vnet_main_t * vnm, u32 hw_if_index, + u32 flags) +{ + af_packet_main_t *apm = &af_packet_main; + vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index); + af_packet_if_t *apif = + pool_elt_at_index (apm->interfaces, hw->dev_instance); + u32 hw_flags; + + apif->is_admin_up = (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) != 0; + + if (apif->is_admin_up) + hw_flags = VNET_HW_INTERFACE_FLAG_LINK_UP; + else + hw_flags = 0; + + vnet_hw_interface_set_flags (vnm, hw_if_index, hw_flags); + + return 0; +} + +static clib_error_t * +af_packet_subif_add_del_function (vnet_main_t * vnm, + u32 hw_if_index, + struct vnet_sw_interface_t *st, int is_add) +{ + /* Nothing for now */ + return 0; +} + +/* *INDENT-OFF* */ +VNET_DEVICE_CLASS (af_packet_device_class) = { + .name = "af-packet", + .tx_function = af_packet_interface_tx, + .format_device_name = format_af_packet_device_name, + .format_device = format_af_packet_device, + .format_tx_trace = format_af_packet_tx_trace, + .tx_function_n_errors = AF_PACKET_TX_N_ERROR, + .tx_function_error_strings = af_packet_tx_func_error_strings, + .rx_redirect_to_node = af_packet_set_interface_next_node, + .clear_counters = af_packet_clear_hw_interface_counters, + .admin_up_down_function = af_packet_interface_admin_up_down, + .subif_add_del_function = af_packet_subif_add_del_function, +}; + +VLIB_DEVICE_TX_FUNCTION_MULTIARCH (af_packet_device_class, + af_packet_interface_tx) +/* *INDENT-ON* */ + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |