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;
95 if (PREDICT_FALSE (apif->lockp != 0))
97 while (__sync_lock_test_and_set (apif->lockp, 1))
110 tph = (struct tpacket2_hdr *) (block_start + tx_frame * frame_size);
113 (tph->tp_status & (TP_STATUS_SEND_REQUEST | TP_STATUS_SENDING)))
121 b0 = vlib_get_buffer (vm, bi);
122 len = b0->current_length;
123 clib_memcpy ((u8 *) tph +
124 TPACKET_ALIGN (sizeof (struct tpacket2_hdr)) + offset,
125 vlib_buffer_get_current (b0), len);
129 (b0->flags & VLIB_BUFFER_NEXT_PRESENT) ? b0->next_buffer : 0));
131 tph->tp_len = tph->tp_snaplen = offset;
132 tph->tp_status = TP_STATUS_SEND_REQUEST;
135 /* check if we've exhausted the ring */
136 if (PREDICT_FALSE (frame_not_ready + n_sent == frame_num))
139 tx_frame = (tx_frame + 1) % frame_num;
142 CLIB_MEMORY_BARRIER ();
144 if (PREDICT_TRUE (n_sent))
146 apif->next_tx_frame = tx_frame;
148 if (PREDICT_FALSE (sendto (apif->fd, NULL, 0,
149 MSG_DONTWAIT, NULL, 0) == -1))
151 /* Uh-oh, drop & move on, but count whether it was fatal or not.
152 * Note that we have no reliable way to properly determine the
153 * disposition of the packets we just enqueued for delivery.
155 vlib_error_count (vm, node->node_index,
156 unix_error_is_fatal (errno) ?
157 AF_PACKET_TX_ERROR_TXRING_FATAL :
158 AF_PACKET_TX_ERROR_TXRING_EAGAIN, n_sent);
162 if (PREDICT_FALSE (apif->lockp != 0))
165 if (PREDICT_FALSE (frame_not_ready))
166 vlib_error_count (vm, node->node_index,
167 AF_PACKET_TX_ERROR_FRAME_NOT_READY, frame_not_ready);
169 if (PREDICT_FALSE (frame_not_ready + n_sent == frame_num))
170 vlib_error_count (vm, node->node_index, AF_PACKET_TX_ERROR_TXRING_OVERRUN,
173 vlib_buffer_free (vm, vlib_frame_args (frame), frame->n_vectors);
174 return frame->n_vectors;
178 af_packet_set_interface_next_node (vnet_main_t * vnm, u32 hw_if_index,
181 af_packet_main_t *apm = &af_packet_main;
182 vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
183 af_packet_if_t *apif =
184 pool_elt_at_index (apm->interfaces, hw->dev_instance);
186 /* Shut off redirection */
187 if (node_index == ~0)
189 apif->per_interface_next_index = node_index;
193 apif->per_interface_next_index =
194 vlib_node_add_next (vlib_get_main (), af_packet_input_node.index,
199 af_packet_clear_hw_interface_counters (u32 instance)
201 /* Nothing for now */
204 static clib_error_t *
205 af_packet_interface_admin_up_down (vnet_main_t * vnm, u32 hw_if_index,
208 af_packet_main_t *apm = &af_packet_main;
209 vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
210 af_packet_if_t *apif =
211 pool_elt_at_index (apm->interfaces, hw->dev_instance);
214 apif->is_admin_up = (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) != 0;
216 if (apif->is_admin_up)
217 hw_flags = VNET_HW_INTERFACE_FLAG_LINK_UP;
221 vnet_hw_interface_set_flags (vnm, hw_if_index, hw_flags);
226 static clib_error_t *
227 af_packet_subif_add_del_function (vnet_main_t * vnm,
229 struct vnet_sw_interface_t *st, int is_add)
231 /* Nothing for now */
236 VNET_DEVICE_CLASS (af_packet_device_class) = {
238 .tx_function = af_packet_interface_tx,
239 .format_device_name = format_af_packet_device_name,
240 .format_device = format_af_packet_device,
241 .format_tx_trace = format_af_packet_tx_trace,
242 .tx_function_n_errors = AF_PACKET_TX_N_ERROR,
243 .tx_function_error_strings = af_packet_tx_func_error_strings,
244 .rx_redirect_to_node = af_packet_set_interface_next_node,
245 .clear_counters = af_packet_clear_hw_interface_counters,
246 .admin_up_down_function = af_packet_interface_admin_up_down,
247 .subif_add_del_function = af_packet_subif_add_del_function,
250 VLIB_DEVICE_TX_FUNCTION_MULTIARCH (af_packet_device_class,
251 af_packet_interface_tx)
255 * fd.io coding-style-patch-verification: ON
258 * eval: (c-set-style "gnu")