/* * replication.c : packet replication * * Copyright (c) 2013 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 <vlib/vlib.h> #include <vnet/vnet.h> #include <vppinfra/error.h> #include <vnet/ip/ip4_packet.h> #include <vnet/replication.h> replication_main_t replication_main; replication_context_t * replication_prep (vlib_main_t * vm, vlib_buffer_t * b0, u32 recycle_node_index, u32 l2_packet) { replication_main_t *rm = &replication_main; replication_context_t *ctx; uword thread_index = vm->thread_index; ip4_header_t *ip; u32 ctx_id; /* Allocate a context, reserve context 0 */ if (PREDICT_FALSE (rm->contexts[thread_index] == 0)) pool_get_aligned (rm->contexts[thread_index], ctx, CLIB_CACHE_LINE_BYTES); pool_get_aligned (rm->contexts[thread_index], ctx, CLIB_CACHE_LINE_BYTES); ctx_id = ctx - rm->contexts[thread_index]; /* Save state from vlib buffer */ ctx->saved_free_list_index = vlib_buffer_get_free_list_index (b0); ctx->current_data = b0->current_data; ctx->flags = b0->flags & VNET_BUFFER_FLAGS_VLAN_BITS; /* Set up vlib buffer hooks */ b0->recycle_count = ctx_id; vlib_buffer_set_free_list_index (b0, rm->recycle_list_index); b0->flags |= VLIB_BUFFER_RECYCLE; /* Save feature state */ ctx->recycle_node_index = recycle_node_index; /* Save vnet state */ clib_memcpy (ctx->vnet_buffer, vnet_buffer (b0), sizeof (vnet_buffer_opaque_t)); /* Save packet contents */ ctx->l2_packet = l2_packet; ip = (ip4_header_t *) vlib_buffer_get_current (b0); if (l2_packet) { /* Save ethernet header */ ctx->l2_header[0] = ((u64 *) ip)[0]; ctx->l2_header[1] = ((u64 *) ip)[1]; ctx->l2_header[2] = ((u64 *) ip)[2]; /* set ip to the true ip header */ ip = (ip4_header_t *) (((u8 *) ip) + vnet_buffer (b0)->l2.l2_len); } /* * Copy L3 fields. * We need to save TOS for ip4 and ip6 packets. * Fortunately the TOS field is * in the first two bytes of both the ip4 and ip6 headers. */ ctx->ip_tos = *((u16 *) (ip)); /* * Save the ip4 checksum as well. We just blindly save the corresponding two * bytes even for ip6 packets. */ ctx->ip4_checksum = ip->checksum; return ctx; } replication_context_t * replication_recycle (vlib_main_t * vm, vlib_buffer_t * b0, u32 is_last) { replication_main_t *rm = &replication_main; replication_context_t *ctx; uword thread_index = vm->thread_index; ip4_header_t *ip; /* Get access to the replication context */ ctx = pool_elt_at_index (rm->contexts[thread_index], b0->recycle_count); /* Restore vnet buffer state */ clib_memcpy (vnet_buffer (b0), ctx->vnet_buffer, sizeof (vnet_buffer_opaque_t)); /* Restore the vlan flags */ b0->flags &= ~VNET_BUFFER_FLAGS_VLAN_BITS; b0->flags |= ctx->flags; /* Restore the packet start (current_data) and length */ vlib_buffer_advance (b0, ctx->current_data - b0->current_data); /* Restore packet contents */ ip = (ip4_header_t *) vlib_buffer_get_current (b0); if (ctx->l2_packet) { /* Restore ethernet header */ ((u64 *) ip)[0] = ctx->l2_header[0]; ((u64 *) ip)[1] = ctx->l2_header[1]; ((u64 *) ip)[2] = ctx->l2_header[2]; /* set ip to the true ip header */ ip = (ip4_header_t *) (((u8 *) ip) + vnet_buffer (b0)->l2.l2_len); } // Restore L3 fields *((u16 *) (ip)) = ctx->ip_tos; ip->checksum = ctx->ip4_checksum; if (is_last) { /* * This is the last replication in the list. * Restore original buffer free functionality. */ vlib_buffer_set_free_list_index (b0, ctx->saved_free_list_index); b0->flags &= ~VLIB_BUFFER_RECYCLE; /* Free context back to its pool */ pool_put (rm->contexts[thread_index], ctx); } return ctx; } /* * fish pkts back from the recycle queue/freelist * un-flatten the context chains */ static void replication_recycle_callback (vlib_main_t * vm, vlib_buffer_free_list_t * fl) { vlib_frame_t *f = 0; u32 n_left_from; u32 n_left_to_next = 0; u32 n_this_frame = 0; u32 *from; u32 *to_next = 0; u32 bi0, pi0; vlib_buffer_t *b0; int i; replication_main_t *rm = &replication_main; replication_context_t *ctx; u32 feature_node_index = 0; uword thread_index = vm->thread_index; /* * All buffers in the list are destined to the same recycle node. * Pull the recycle node index from the first buffer. * Note: this could be sped up if the node index were stuffed into * the freelist itself. */ if (vec_len (fl->buffers) > 0) { bi0 = fl->buffers[0]; b0 = vlib_get_buffer (vm, bi0); ctx = pool_elt_at_index (rm->contexts[thread_index], b0->recycle_count); feature_node_index = ctx->recycle_node_index; } /* buffers */ for (i = 0; i < 2; i++) { if (i == 0) { from = fl->buffers; n_left_from = vec_len (from); } while (n_left_from > 0) { if (PREDICT_FALSE (n_left_to_next == 0)) { if (f) { f->n_vectors = n_this_frame; vlib_put_frame_to_node (vm, feature_node_index, f); } f = vlib_get_frame_to_node (vm, feature_node_index); to_next = vlib_frame_vector_args (f); n_left_to_next = VLIB_FRAME_SIZE; n_this_frame = 0; } bi0 = from[0]; if (PREDICT_TRUE (n_left_from > 1)) { pi0 = from[1]; vlib_prefetch_buffer_with_index (vm, pi0, LOAD); } b0 = vlib_get_buffer (vm, bi0); /* Mark that this buffer was just recycled */ b0->flags |= VLIB_BUFFER_IS_RECYCLED; #if (CLIB_DEBUG > 0) if (vm->buffer_main->callbacks_registered == 0) vlib_buffer_set_known_state (vm, bi0, VLIB_BUFFER_KNOWN_ALLOCATED); #endif /* If buffer is traced, mark frame as traced */ if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED)) f->flags |= VLIB_FRAME_TRACE; to_next[0] = bi0; from++; to_next++; n_this_frame++; n_left_to_next--; n_left_from--; } } vec_reset_length (fl->buffers); if (f) { ASSERT (n_this_frame); f->n_vectors = n_this_frame; vlib_put_frame_to_node (vm, feature_node_index, f); } } clib_error_t * replication_init (vlib_main_t * vm) { replication_main_t *rm = &replication_main; vlib_buffer_main_t *bm = vm->buffer_main; vlib_buffer_free_list_t *fl; __attribute__ ((unused)) replication_context_t *ctx; vlib_thread_main_t *tm = vlib_get_thread_main (); rm->vlib_main = vm; rm->vnet_main = vnet_get_main (); rm->recycle_list_index = vlib_buffer_create_free_list (vm, 1024 /* fictional */ , "replication-recycle"); fl = pool_elt_at_index (bm->buffer_free_list_pool, rm->recycle_list_index); fl->buffers_added_to_freelist_function = replication_recycle_callback; /* Verify the replication context is the expected size */ ASSERT (sizeof (replication_context_t) == 128); /* 2 cache lines */ vec_validate (rm->contexts, tm->n_vlib_mains - 1); return 0; } VLIB_INIT_FUNCTION (replication_init); /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */