/* *------------------------------------------------------------------ * 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 <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <vlib/vlib.h> #include <vlib/unix/unix.h> #include <vnet/ethernet/ethernet.h> #include <vnet/gso/gso.h> #include <vnet/ip/ip4_packet.h> #include <vnet/ip/ip6_packet.h> #include <vnet/tcp/tcp_packet.h> #include <vnet/udp/udp_packet.h> #include <vnet/devices/virtio/virtio.h> #define foreach_virtio_tx_func_error \ _(NO_FREE_SLOTS, "no free tx slots") \ _(TRUNC_PACKET, "packet > buffer size -- truncated in tx ring") \ _(PENDING_MSGS, "pending msgs in tx ring") \ _(NO_TX_QUEUES, "no tx queues") \ _(OUT_OF_ORDER, "out-of-order buffers in used ring") typedef enum { #define _(f,s) VIRTIO_TX_ERROR_##f, foreach_virtio_tx_func_error #undef _ VIRTIO_TX_N_ERROR, } virtio_tx_func_error_t; static char *virtio_tx_func_error_strings[] = { #define _(n,s) s, foreach_virtio_tx_func_error #undef _ }; static u8 * format_virtio_device (u8 * s, va_list * args) { u32 dev_instance = va_arg (*args, u32); int verbose = va_arg (*args, int); u32 indent = format_get_indent (s); s = format (s, "VIRTIO interface"); if (verbose) { s = format (s, "\n%U instance %u", format_white_space, indent + 2, dev_instance); } return s; } static u8 * format_virtio_tx_trace (u8 * s, va_list * args) { s = format (s, "Unimplemented..."); return s; } static_always_inline void virtio_memset_ring_u32 (u32 * ring, u32 start, u32 ring_size, u32 n_buffers) { ASSERT (n_buffers <= ring_size); if (PREDICT_TRUE (start + n_buffers <= ring_size)) { clib_memset_u32 (ring + start, ~0, n_buffers); } else { clib_memset_u32 (ring + start, ~0, ring_size - start); clib_memset_u32 (ring, ~0, n_buffers - (ring_size - start)); } } static_always_inline void virtio_free_used_device_desc (vlib_main_t * vm, virtio_vring_t * vring, uword node_index) { u16 used = vring->desc_in_use; u16 sz = vring->size; u16 mask = sz - 1; u16 last = vring->last_used_idx; u16 n_left = vring->used->idx - last; u16 out_of_order_count = 0; if (n_left == 0) return; while (n_left) { struct vring_used_elem *e = &vring->used->ring[last & mask]; u16 slot, n_buffers; slot = n_buffers = e->id; while (e->id == (n_buffers & mask)) { n_left--; last++; n_buffers++; if (n_left == 0) break; e = &vring->used->ring[last & mask]; } vlib_buffer_free_from_ring (vm, vring->buffers, slot, sz, (n_buffers - slot)); virtio_memset_ring_u32 (vring->buffers, slot, sz, (n_buffers - slot)); used -= (n_buffers - slot); if (n_left > 0) { vlib_buffer_free (vm, &vring->buffers[e->id], 1); vring->buffers[e->id] = ~0; used--; last++; n_left--; out_of_order_count++; vring->flags |= VRING_TX_OUT_OF_ORDER; } } /* * Some vhost-backends give buffers back in out-of-order fashion in used ring. * It impacts the overall virtio-performance. */ if (out_of_order_count) vlib_error_count (vm, node_index, VIRTIO_TX_ERROR_OUT_OF_ORDER, out_of_order_count); vring->desc_in_use = used; vring->last_used_idx = last; } static_always_inline void set_checksum_offsets (vlib_main_t * vm, virtio_if_t * vif, vlib_buffer_t * b, struct virtio_net_hdr_v1 *hdr) { if (b->flags & VNET_BUFFER_F_IS_IP4) { ip4_header_t *ip4; gso_header_offset_t gho = vnet_gso_header_offset_parser (b, 0); hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; hdr->csum_start = gho.l4_hdr_offset; // 0x22; if (b->flags & VNET_BUFFER_F_OFFLOAD_TCP_CKSUM) hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum); else if (b->flags & VNET_BUFFER_F_OFFLOAD_UDP_CKSUM) hdr->csum_offset = STRUCT_OFFSET_OF (udp_header_t, checksum); /* * virtio devices do not support IP4 checksum offload. So driver takes care * of it while doing tx. */ ip4 = (ip4_header_t *) (vlib_buffer_get_current (b) + gho.l3_hdr_offset); if (b->flags & VNET_BUFFER_F_OFFLOAD_IP_CKSUM) ip4->checksum = ip4_header_checksum (ip4); } else if (b->flags & VNET_BUFFER_F_IS_IP6) { gso_header_offset_t gho = vnet_gso_header_offset_parser (b, 1); hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; hdr->csum_start = gho.l4_hdr_offset; // 0x36; if (b->flags & VNET_BUFFER_F_OFFLOAD_TCP_CKSUM) hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum); else if (b->flags & VNET_BUFFER_F_OFFLOAD_UDP_CKSUM) hdr->csum_offset = STRUCT_OFFSET_OF (udp_header_t, checksum); } } static_always_inline u16 add_buffer_to_slot (vlib_main_t * vm, virtio_if_t * vif, virtio_vring_t * vring, u32 bi, u16 avail, u16 next, u16 mask, int do_gso, int csum_offload) { u16 n_added = 0; int hdr_sz = vif->virtio_net_hdr_sz; struct vring_desc *d; d = &vring->desc[next]; vlib_buffer_t *b = vlib_get_buffer (vm, bi); struct virtio_net_hdr_v1 *hdr = vlib_buffer_get_current (b) - hdr_sz; clib_memset (hdr, 0, hdr_sz); if (do_gso && (b->flags & VNET_BUFFER_F_GSO)) { if (b->flags & VNET_BUFFER_F_IS_IP4) { ip4_header_t *ip4; gso_header_offset_t gho = vnet_gso_header_offset_parser (b, 0); hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4; hdr->gso_size = vnet_buffer2 (b)->gso_size; hdr->hdr_len = gho.l4_hdr_offset + gho.l4_hdr_sz; hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; hdr->csum_start = gho.l4_hdr_offset; // 0x22; hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum); ip4 = (ip4_header_t *) (vlib_buffer_get_current (b) + gho.l3_hdr_offset); /* * virtio devices do not support IP4 checksum offload. So driver takes care * of it while doing tx. */ if (b->flags & VNET_BUFFER_F_OFFLOAD_IP_CKSUM) ip4->checksum = ip4_header_checksum (ip4); } else if (b->flags & VNET_BUFFER_F_IS_IP6) { gso_header_offset_t gho = vnet_gso_header_offset_parser (b, 1); hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6; hdr->gso_size = vnet_buffer2 (b)->gso_size; hdr->hdr_len = gho.l4_hdr_offset + gho.l4_hdr_sz; hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; hdr->csum_start = gho.l4_hdr_offset; // 0x36; hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum); } } else if (csum_offload && (b->flags & (VNET_BUFFER_F_OFFLOAD_TCP_CKSUM | VNET_BUFFER_F_OFFLOAD_UDP_CKSUM))) { set_checksum_offsets (vm, vif, b, hdr); } if (PREDICT_TRUE ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0)) { d->addr = ((vif->type == VIRTIO_IF_TYPE_PCI) ? vlib_buffer_get_current_pa (vm, b) : pointer_to_uword (vlib_buffer_get_current (b))) - hdr_sz; d->len = b->current_length + hdr_sz; d->flags = 0; } else { /* * We are using single vlib_buffer_t for indirect descriptor(s) * chain. Single descriptor is 16 bytes and vlib_buffer_t * has 2048 bytes space. So maximum long chain can have 128 * (=2048/16) indirect descriptors. * It can easily support 65535 bytes of Jumbo frames with * each data buffer size of 512 bytes minimum. */ u32 indirect_buffer = 0; if (PREDICT_FALSE (vlib_buffer_alloc (vm, &indirect_buffer, 1) == 0)) return n_added; vlib_buffer_t *indirect_desc = vlib_get_buffer (vm, indirect_buffer); indirect_desc->current_data = 0; indirect_desc->flags |= VLIB_BUFFER_NEXT_PRESENT; indirect_desc->next_buffer = bi; bi = indirect_buffer; struct vring_desc *id = (struct vring_desc *) vlib_buffer_get_current (indirect_desc); u32 count = 1; if (vif->type == VIRTIO_IF_TYPE_PCI) { d->addr = vlib_physmem_get_pa (vm, id); id->addr = vlib_buffer_get_current_pa (vm, b) - hdr_sz; /* * If VIRTIO_F_ANY_LAYOUT is not negotiated, then virtio_net_hdr * should be presented in separate descriptor and data will start * from next descriptor. */ if (PREDICT_TRUE (vif->features & VIRTIO_FEATURE (VIRTIO_F_ANY_LAYOUT))) id->len = b->current_length + hdr_sz; else { id->len = hdr_sz; id->flags = VRING_DESC_F_NEXT; id->next = count; count++; id++; id->addr = vlib_buffer_get_current_pa (vm, b); id->len = b->current_length; } while (b->flags & VLIB_BUFFER_NEXT_PRESENT) { id->flags = VRING_DESC_F_NEXT; id->next = count; count++; id++; b = vlib_get_buffer (vm, b->next_buffer); id->addr = vlib_buffer_get_current_pa (vm, b); id->len = b->current_length; } } else /* VIRTIO_IF_TYPE_TAP */ { d->addr = pointer_to_uword (id); /* first buffer in chain */ id->addr = pointer_to_uword (vlib_buffer_get_current (b)) - hdr_sz; id->len = b->current_length + hdr_sz; while (b->flags & VLIB_BUFFER_NEXT_PRESENT) { id->flags = VRING_DESC_F_NEXT; id->next = count; count++; id++; b = vlib_get_buffer (vm, b->next_buffer); id->addr = pointer_to_uword (vlib_buffer_get_current (b)); id->len = b->current_length; } } id->flags = 0; id->next = 0; d->len = count * sizeof (struct vring_desc); d->flags = VRING_DESC_F_INDIRECT; } vring->buffers[next] = bi; vring->avail->ring[avail & mask] = next; n_added++; return n_added; } static_always_inline void virtio_find_free_desc (virtio_vring_t * vring, u16 size, u16 mask, u16 req, u16 next, u32 * first_free_desc_index, u16 * free_desc_count) { u16 start = 0; /* next is used as hint: from where to start looking */ for (u16 i = 0; i < size; i++, next++) { if (vring->buffers[next & mask] == ~0) { if (*first_free_desc_index == ~0) { *first_free_desc_index = (next & mask); start = i; (*free_desc_count)++; req--; if (req == 0) break; } else { if (start + *free_desc_count == i) { (*free_desc_count)++; req--; if (req == 0) break; } else break; } } } } static_always_inline uword virtio_interface_tx_inline (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame, virtio_if_t * vif, int do_gso, int csum_offload) { u16 n_left = frame->n_vectors; virtio_vring_t *vring; u16 qid = vm->thread_index % vif->num_txqs; vring = vec_elt_at_index (vif->txq_vrings, qid); u16 used, next, avail; u16 sz = vring->size; u16 mask = sz - 1; u16 retry_count = 2; u32 *buffers = vlib_frame_vector_args (frame); clib_spinlock_lock_if_init (&vring->lockp); if ((vring->used->flags & VIRTIO_RING_FLAG_MASK_INT) == 0 && (vring->last_kick_avail_idx != vring->avail->idx)) virtio_kick (vm, vring, vif); retry: /* free consumed buffers */ virtio_free_used_device_desc (vm, vring, node->node_index); used = vring->desc_in_use; next = vring->desc_next; avail = vring->avail->idx; u16 free_desc_count = 0; if (PREDICT_FALSE (vring->flags & VRING_TX_OUT_OF_ORDER)) { u32 first_free_desc_index = ~0; virtio_find_free_desc (vring, sz, mask, n_left, next, &first_free_desc_index, &free_desc_count); if (free_desc_count) next = first_free_desc_index; } else free_desc_count = sz - used; while (n_left && free_desc_count) { u16 n_added = 0; n_added = add_buffer_to_slot (vm, vif, vring, buffers[0], avail, next, mask, do_gso, csum_offload); if (!n_added) break; avail += n_added; next = (next + n_added) & mask; used += n_added; buffers++; n_left--; free_desc_count--; } if (n_left != frame->n_vectors) { CLIB_MEMORY_STORE_BARRIER (); vring->avail->idx = avail; vring->desc_next = next; vring->desc_in_use = used; if ((vring->used->flags & VIRTIO_RING_FLAG_MASK_INT) == 0) virtio_kick (vm, vring, vif); } if (n_left) { if (retry_count--) goto retry; vlib_error_count (vm, node->node_index, VIRTIO_TX_ERROR_NO_FREE_SLOTS, n_left); vlib_buffer_free (vm, buffers, n_left); } clib_spinlock_unlock_if_init (&vring->lockp); return frame->n_vectors - n_left; } VNET_DEVICE_CLASS_TX_FN (virtio_device_class) (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { vnet_main_t *vnm = vnet_get_main (); virtio_main_t *nm = &virtio_main; vnet_interface_output_runtime_t *rund = (void *) node->runtime_data; virtio_if_t *vif = pool_elt_at_index (nm->interfaces, rund->dev_instance); vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, vif->hw_if_index); if (hw->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_GSO) return virtio_interface_tx_inline (vm, node, frame, vif, 1 /* do_gso */ , 1); else if (hw->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_TX_L4_CKSUM_OFFLOAD) return virtio_interface_tx_inline (vm, node, frame, vif, 0 /* no do_gso */ , 1); else return virtio_interface_tx_inline (vm, node, frame, vif, 0 /* no do_gso */ , 0); } static void virtio_set_interface_next_node (vnet_main_t * vnm, u32 hw_if_index, u32 node_index) { virtio_main_t *apm = &virtio_main; vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index); virtio_if_t *vif = pool_elt_at_index (apm->interfaces, hw->dev_instance); /* Shut off redirection */ if (node_index == ~0) { vif->per_interface_next_index = node_index; return; } vif->per_interface_next_index = vlib_node_add_next (vlib_get_main (), virtio_input_node.index, node_index); } static void virtio_clear_hw_interface_counters (u32 instance) { /* Nothing for now */ } static clib_error_t * virtio_interface_rx_mode_change (vnet_main_t * vnm, u32 hw_if_index, u32 qid, vnet_hw_interface_rx_mode mode) { virtio_main_t *mm = &virtio_main; vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index); virtio_if_t *vif = pool_elt_at_index (mm->interfaces, hw->dev_instance); virtio_vring_t *vring = vec_elt_at_index (vif->rxq_vrings, qid); if (vif->type == VIRTIO_IF_TYPE_PCI && !(vif->support_int_mode)) { vring->avail->flags |= VIRTIO_RING_FLAG_MASK_INT; return clib_error_return (0, "interrupt mode is not supported"); } if (mode == VNET_HW_INTERFACE_RX_MODE_POLLING) vring->avail->flags |= VIRTIO_RING_FLAG_MASK_INT; else vring->avail->flags &= ~VIRTIO_RING_FLAG_MASK_INT; return 0; } static clib_error_t * virtio_interface_admin_up_down (vnet_main_t * vnm, u32 hw_if_index, u32 flags) { virtio_main_t *mm = &virtio_main; vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index); virtio_if_t *vif = pool_elt_at_index (mm->interfaces, hw->dev_instance); if (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) { vif->flags |= VIRTIO_IF_FLAG_ADMIN_UP; vnet_hw_interface_set_flags (vnm, vif->hw_if_index, VNET_HW_INTERFACE_FLAG_LINK_UP); } else { vif->flags &= ~VIRTIO_IF_FLAG_ADMIN_UP; vnet_hw_interface_set_flags (vnm, vif->hw_if_index, 0); } return 0; } static clib_error_t * virtio_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 (virtio_device_class) = { .name = "virtio", .format_device_name = format_virtio_device_name, .format_device = format_virtio_device, .format_tx_trace = format_virtio_tx_trace, .tx_function_n_errors = VIRTIO_TX_N_ERROR, .tx_function_error_strings = virtio_tx_func_error_strings, .rx_redirect_to_node = virtio_set_interface_next_node, .clear_counters = virtio_clear_hw_interface_counters, .admin_up_down_function = virtio_interface_admin_up_down, .subif_add_del_function = virtio_subif_add_del_function, .rx_mode_change_function = virtio_interface_rx_mode_change, }; /* *INDENT-ON* */ /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */