2 *------------------------------------------------------------------
3 * af_packet.c - linux kernel packet interface
5 * Copyright (c) 2016 Cisco and/or its affiliates.
6 * Licensed under the Apache License, Version 2.0 (the "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at:
10 * http://www.apache.org/licenses/LICENSE-2.0
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
17 *------------------------------------------------------------------
20 #include <linux/if_packet.h>
22 #include <vlib/vlib.h>
23 #include <vlib/unix/unix.h>
24 #include <vnet/ip/ip.h>
25 #include <vnet/ethernet/ethernet.h>
27 #include <vnet/devices/af_packet/af_packet.h>
29 #define foreach_af_packet_tx_func_error \
30 _(FRAME_NOT_READY, "tx frame not ready") \
31 _(TXRING_EAGAIN, "tx sendto temporary failure") \
32 _(TXRING_FATAL, "tx sendto fatal failure") \
33 _(TXRING_OVERRUN, "tx ring overrun")
37 #define _(f,s) AF_PACKET_TX_ERROR_##f,
38 foreach_af_packet_tx_func_error
41 } af_packet_tx_func_error_t;
43 static char *af_packet_tx_func_error_strings[] = {
45 foreach_af_packet_tx_func_error
51 format_af_packet_device_name (u8 * s, va_list * args)
53 u32 i = va_arg (*args, u32);
54 af_packet_main_t *apm = &af_packet_main;
55 af_packet_if_t *apif = pool_elt_at_index (apm->interfaces, i);
57 s = format (s, "host-%s", apif->host_if_name);
62 format_af_packet_device (u8 * s, va_list * args)
64 s = format (s, "Linux PACKET socket interface");
69 format_af_packet_tx_trace (u8 * s, va_list * args)
71 s = format (s, "Unimplemented...");
76 af_packet_interface_tx (vlib_main_t * vm,
77 vlib_node_runtime_t * node, vlib_frame_t * frame)
79 af_packet_main_t *apm = &af_packet_main;
80 u32 *buffers = vlib_frame_args (frame);
81 u32 n_left = frame->n_vectors;
83 vnet_interface_output_runtime_t *rd = (void *) node->runtime_data;
84 af_packet_if_t *apif =
85 pool_elt_at_index (apm->interfaces, rd->dev_instance);
87 u32 block_size = apif->tx_req->tp_block_size;
88 u32 frame_size = apif->tx_req->tp_frame_size;
89 u32 frame_num = apif->tx_req->tp_frame_nr;
90 u8 *block_start = apif->tx_ring + block * block_size;
91 u32 tx_frame = apif->next_tx_frame;
92 struct tpacket2_hdr *tph;
93 u32 frame_not_ready = 0;
104 tph = (struct tpacket2_hdr *) (block_start + tx_frame * frame_size);
107 (tph->tp_status & (TP_STATUS_SEND_REQUEST | TP_STATUS_SENDING)))
115 b0 = vlib_get_buffer (vm, bi);
116 len = b0->current_length;
117 clib_memcpy ((u8 *) tph +
118 TPACKET_ALIGN (sizeof (struct tpacket2_hdr)) + offset,
119 vlib_buffer_get_current (b0), len);
122 while ((bi = b0->next_buffer));
124 tph->tp_len = tph->tp_snaplen = offset;
125 tph->tp_status = TP_STATUS_SEND_REQUEST;
128 /* check if we've exhausted the ring */
129 if (PREDICT_FALSE (frame_not_ready + n_sent == frame_num))
132 tx_frame = (tx_frame + 1) % frame_num;
135 CLIB_MEMORY_BARRIER ();
137 if (PREDICT_TRUE (n_sent))
139 apif->next_tx_frame = tx_frame;
141 if (PREDICT_FALSE (sendto (apif->fd, NULL, 0,
142 MSG_DONTWAIT, NULL, 0) == -1))
144 /* Uh-oh, drop & move on, but count whether it was fatal or not.
145 * Note that we have no reliable way to properly determine the
146 * disposition of the packets we just enqueued for delivery.
148 vlib_error_count (vm, node->node_index,
149 unix_error_is_fatal (errno) ?
150 AF_PACKET_TX_ERROR_TXRING_FATAL :
151 AF_PACKET_TX_ERROR_TXRING_EAGAIN, n_sent);
155 if (PREDICT_FALSE (frame_not_ready))
156 vlib_error_count (vm, node->node_index,
157 AF_PACKET_TX_ERROR_FRAME_NOT_READY, frame_not_ready);
159 if (PREDICT_FALSE (frame_not_ready + n_sent == frame_num))
160 vlib_error_count (vm, node->node_index, AF_PACKET_TX_ERROR_TXRING_OVERRUN,
163 vlib_buffer_free (vm, vlib_frame_args (frame), frame->n_vectors);
164 return frame->n_vectors;
168 af_packet_set_interface_next_node (vnet_main_t * vnm, u32 hw_if_index,
171 af_packet_main_t *apm = &af_packet_main;
172 vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
173 af_packet_if_t *apif =
174 pool_elt_at_index (apm->interfaces, hw->dev_instance);
176 /* Shut off redirection */
177 if (node_index == ~0)
179 apif->per_interface_next_index = node_index;
183 apif->per_interface_next_index =
184 vlib_node_add_next (vlib_get_main (), af_packet_input_node.index,
189 af_packet_clear_hw_interface_counters (u32 instance)
191 /* Nothing for now */
194 static clib_error_t *
195 af_packet_interface_admin_up_down (vnet_main_t * vnm, u32 hw_if_index,
198 af_packet_main_t *apm = &af_packet_main;
199 vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
200 af_packet_if_t *apif =
201 pool_elt_at_index (apm->interfaces, hw->dev_instance);
204 apif->is_admin_up = (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) != 0;
206 if (apif->is_admin_up)
207 hw_flags = VNET_HW_INTERFACE_FLAG_LINK_UP;
211 vnet_hw_interface_set_flags (vnm, hw_if_index, hw_flags);
216 static clib_error_t *
217 af_packet_subif_add_del_function (vnet_main_t * vnm,
219 struct vnet_sw_interface_t *st, int is_add)
221 /* Nothing for now */
226 VNET_DEVICE_CLASS (af_packet_device_class) = {
228 .tx_function = af_packet_interface_tx,
229 .format_device_name = format_af_packet_device_name,
230 .format_device = format_af_packet_device,
231 .format_tx_trace = format_af_packet_tx_trace,
232 .tx_function_n_errors = AF_PACKET_TX_N_ERROR,
233 .tx_function_error_strings = af_packet_tx_func_error_strings,
234 .rx_redirect_to_node = af_packet_set_interface_next_node,
235 .clear_counters = af_packet_clear_hw_interface_counters,
236 .admin_up_down_function = af_packet_interface_admin_up_down,
237 .subif_add_del_function = af_packet_subif_add_del_function,
238 .no_flatten_output_chains = 1,
241 VLIB_DEVICE_TX_FUNCTION_MULTIARCH (af_packet_device_class,
242 af_packet_interface_tx)
246 * fd.io coding-style-patch-verification: ON
249 * eval: (c-set-style "gnu")