diff options
Diffstat (limited to 'src/vnet/devices/af_packet/node.c')
| -rw-r--r-- | src/vnet/devices/af_packet/node.c | 288 |
1 files changed, 288 insertions, 0 deletions
diff --git a/src/vnet/devices/af_packet/node.c b/src/vnet/devices/af_packet/node.c new file mode 100644 index 00000000000..72004320c67 --- /dev/null +++ b/src/vnet/devices/af_packet/node.c @@ -0,0 +1,288 @@ +/* + *------------------------------------------------------------------ + * 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/devices.h> +#include <vnet/feature/feature.h> + +#include <vnet/devices/af_packet/af_packet.h> + +#define foreach_af_packet_input_error + +typedef enum +{ +#define _(f,s) AF_PACKET_INPUT_ERROR_##f, + foreach_af_packet_input_error +#undef _ + AF_PACKET_INPUT_N_ERROR, +} af_packet_input_error_t; + +static char *af_packet_input_error_strings[] = { +#define _(n,s) s, + foreach_af_packet_input_error +#undef _ +}; + +typedef struct +{ + u32 next_index; + u32 hw_if_index; + int block; + struct tpacket2_hdr tph; +} af_packet_input_trace_t; + +static u8 * +format_af_packet_input_trace (u8 * s, va_list * args) +{ + CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *); + CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *); + af_packet_input_trace_t *t = va_arg (*args, af_packet_input_trace_t *); + uword indent = format_get_indent (s); + + s = format (s, "af_packet: hw_if_index %d next-index %d", + t->hw_if_index, t->next_index); + + s = + format (s, + "\n%Utpacket2_hdr:\n%Ustatus 0x%x len %u snaplen %u mac %u net %u" + "\n%Usec 0x%x nsec 0x%x vlan %U" +#ifdef TP_STATUS_VLAN_TPID_VALID + " vlan_tpid %u" +#endif + , + format_white_space, indent + 2, + format_white_space, indent + 4, + t->tph.tp_status, + t->tph.tp_len, + t->tph.tp_snaplen, + t->tph.tp_mac, + t->tph.tp_net, + format_white_space, indent + 4, + t->tph.tp_sec, + t->tph.tp_nsec, format_ethernet_vlan_tci, t->tph.tp_vlan_tci +#ifdef TP_STATUS_VLAN_TPID_VALID + , t->tph.tp_vlan_tpid +#endif + ); + return s; +} + +always_inline void +buffer_add_to_chain (vlib_main_t * vm, u32 bi, u32 first_bi, u32 prev_bi) +{ + vlib_buffer_t *b = vlib_get_buffer (vm, bi); + vlib_buffer_t *first_b = vlib_get_buffer (vm, first_bi); + vlib_buffer_t *prev_b = vlib_get_buffer (vm, prev_bi); + + /* update first buffer */ + first_b->total_length_not_including_first_buffer += b->current_length; + + /* update previous buffer */ + prev_b->next_buffer = bi; + prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT; + + /* update current buffer */ + b->next_buffer = 0; +} + +always_inline uword +af_packet_device_input_fn (vlib_main_t * vm, vlib_node_runtime_t * node, + vlib_frame_t * frame, u32 device_idx) +{ + af_packet_main_t *apm = &af_packet_main; + af_packet_if_t *apif = pool_elt_at_index (apm->interfaces, device_idx); + struct tpacket2_hdr *tph; + u32 next_index = VNET_DEVICE_INPUT_NEXT_ETHERNET_INPUT; + u32 block = 0; + u32 rx_frame; + u32 n_free_bufs; + u32 n_rx_packets = 0; + u32 n_rx_bytes = 0; + u32 *to_next = 0; + u32 block_size = apif->rx_req->tp_block_size; + u32 frame_size = apif->rx_req->tp_frame_size; + u32 frame_num = apif->rx_req->tp_frame_nr; + u8 *block_start = apif->rx_ring + block * block_size; + uword n_trace = vlib_get_trace_count (vm, node); + u32 n_buffer_bytes = vlib_buffer_free_list_buffer_size (vm, + VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX); + u32 min_bufs = apif->rx_req->tp_frame_size / n_buffer_bytes; + int cpu_index = node->cpu_index; + + if (apif->per_interface_next_index != ~0) + next_index = apif->per_interface_next_index; + + n_free_bufs = vec_len (apm->rx_buffers[cpu_index]); + if (PREDICT_FALSE (n_free_bufs < VLIB_FRAME_SIZE)) + { + vec_validate (apm->rx_buffers[cpu_index], + VLIB_FRAME_SIZE + n_free_bufs - 1); + n_free_bufs += + vlib_buffer_alloc (vm, &apm->rx_buffers[cpu_index][n_free_bufs], + VLIB_FRAME_SIZE); + _vec_len (apm->rx_buffers[cpu_index]) = n_free_bufs; + } + + rx_frame = apif->next_rx_frame; + tph = (struct tpacket2_hdr *) (block_start + rx_frame * frame_size); + while ((tph->tp_status & TP_STATUS_USER) && (n_free_bufs > min_bufs)) + { + vlib_buffer_t *b0 = 0, *first_b0 = 0; + u32 next0 = next_index; + + u32 n_left_to_next; + vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); + while ((tph->tp_status & TP_STATUS_USER) && (n_free_bufs > min_bufs) && + n_left_to_next) + { + u32 data_len = tph->tp_snaplen; + u32 offset = 0; + u32 bi0 = 0, first_bi0 = 0, prev_bi0; + + while (data_len) + { + /* grab free buffer */ + u32 last_empty_buffer = + vec_len (apm->rx_buffers[cpu_index]) - 1; + prev_bi0 = bi0; + bi0 = apm->rx_buffers[cpu_index][last_empty_buffer]; + b0 = vlib_get_buffer (vm, bi0); + _vec_len (apm->rx_buffers[cpu_index]) = last_empty_buffer; + n_free_bufs--; + + /* copy data */ + u32 bytes_to_copy = + data_len > n_buffer_bytes ? n_buffer_bytes : data_len; + b0->current_data = 0; + clib_memcpy (vlib_buffer_get_current (b0), + (u8 *) tph + tph->tp_mac + offset, bytes_to_copy); + + /* fill buffer header */ + b0->current_length = bytes_to_copy; + + if (offset == 0) + { + b0->total_length_not_including_first_buffer = 0; + b0->flags = VLIB_BUFFER_TOTAL_LENGTH_VALID; + vnet_buffer (b0)->sw_if_index[VLIB_RX] = apif->sw_if_index; + vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0; + first_bi0 = bi0; + first_b0 = vlib_get_buffer (vm, first_bi0); + } + else + buffer_add_to_chain (vm, bi0, first_bi0, prev_bi0); + + offset += bytes_to_copy; + data_len -= bytes_to_copy; + } + n_rx_packets++; + n_rx_bytes += tph->tp_snaplen; + to_next[0] = first_bi0; + to_next += 1; + n_left_to_next--; + + /* trace */ + VLIB_BUFFER_TRACE_TRAJECTORY_INIT (first_b0); + if (PREDICT_FALSE (n_trace > 0)) + { + af_packet_input_trace_t *tr; + vlib_trace_buffer (vm, node, next0, first_b0, /* follow_chain */ + 0); + vlib_set_trace_count (vm, node, --n_trace); + tr = vlib_add_trace (vm, node, first_b0, sizeof (*tr)); + tr->next_index = next0; + tr->hw_if_index = apif->hw_if_index; + clib_memcpy (&tr->tph, tph, sizeof (struct tpacket2_hdr)); + } + + /* redirect if feature path enabled */ + vnet_feature_start_device_input_x1 (apif->sw_if_index, &next0, b0, + 0); + + /* enque and take next packet */ + vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, + n_left_to_next, first_bi0, next0); + + /* next packet */ + tph->tp_status = TP_STATUS_KERNEL; + rx_frame = (rx_frame + 1) % frame_num; + tph = (struct tpacket2_hdr *) (block_start + rx_frame * frame_size); + } + + vlib_put_next_frame (vm, node, next_index, n_left_to_next); + } + + apif->next_rx_frame = rx_frame; + + vlib_increment_combined_counter + (vnet_get_main ()->interface_main.combined_sw_if_counters + + VNET_INTERFACE_COUNTER_RX, + os_get_cpu_number (), apif->hw_if_index, n_rx_packets, n_rx_bytes); + + return n_rx_packets; +} + +static uword +af_packet_input_fn (vlib_main_t * vm, vlib_node_runtime_t * node, + vlib_frame_t * frame) +{ + int i; + u32 n_rx_packets = 0; + + af_packet_main_t *apm = &af_packet_main; + + /* *INDENT-OFF* */ + clib_bitmap_foreach (i, apm->pending_input_bitmap, + ({ + clib_bitmap_set (apm->pending_input_bitmap, i, 0); + n_rx_packets += af_packet_device_input_fn(vm, node, frame, i); + })); + /* *INDENT-ON* */ + + return n_rx_packets; +} + +/* *INDENT-OFF* */ +VLIB_REGISTER_NODE (af_packet_input_node) = { + .function = af_packet_input_fn, + .name = "af-packet-input", + .sibling_of = "device-input", + .format_trace = format_af_packet_input_trace, + .type = VLIB_NODE_TYPE_INPUT, + .state = VLIB_NODE_STATE_INTERRUPT, + .n_errors = AF_PACKET_INPUT_N_ERROR, + .error_strings = af_packet_input_error_strings, +}; + +VLIB_NODE_FUNCTION_MULTIARCH (af_packet_input_node, af_packet_input_fn) +/* *INDENT-ON* */ + + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |