2 *------------------------------------------------------------------
3 * Copyright (c) 2016 Cisco and/or its affiliates.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 *------------------------------------------------------------------
18 #include <sys/types.h>
22 #include <vlib/vlib.h>
23 #include <vlib/unix/unix.h>
24 #include <vnet/ethernet/ethernet.h>
25 #include <vnet/gso/gso.h>
26 #include <vnet/ip/ip4_packet.h>
27 #include <vnet/ip/ip6_packet.h>
28 #include <vnet/tcp/tcp_packet.h>
29 #include <vnet/udp/udp_packet.h>
30 #include <vnet/devices/virtio/virtio.h>
32 #define foreach_virtio_tx_func_error \
33 _(NO_FREE_SLOTS, "no free tx slots") \
34 _(TRUNC_PACKET, "packet > buffer size -- truncated in tx ring") \
35 _(PENDING_MSGS, "pending msgs in tx ring") \
36 _(INDIRECT_DESC_ALLOC_FAILED, "indirect descriptor allocation failed - packet drop") \
37 _(OUT_OF_ORDER, "out-of-order buffers in used ring") \
38 _(GSO_PACKET_DROP, "gso disabled on itf -- gso packet drop") \
39 _(CSUM_OFFLOAD_PACKET_DROP, "checksum offload disabled on itf -- csum offload packet drop")
43 #define _(f,s) VIRTIO_TX_ERROR_##f,
44 foreach_virtio_tx_func_error
47 } virtio_tx_func_error_t;
49 static char *virtio_tx_func_error_strings[] = {
51 foreach_virtio_tx_func_error
56 format_virtio_device (u8 * s, va_list * args)
58 u32 dev_instance = va_arg (*args, u32);
59 int verbose = va_arg (*args, int);
60 u32 indent = format_get_indent (s);
62 s = format (s, "VIRTIO interface");
65 s = format (s, "\n%U instance %u", format_white_space, indent + 2,
72 format_virtio_tx_trace (u8 * s, va_list * args)
74 s = format (s, "Unimplemented...");
78 static_always_inline void
79 virtio_interface_drop_inline (vlib_main_t * vm, uword node_index,
81 virtio_tx_func_error_t error)
83 vlib_error_count (vm, node_index, error, n);
84 vlib_buffer_free (vm, buffers, n);
87 static_always_inline void
88 virtio_memset_ring_u32 (u32 * ring, u32 start, u32 ring_size, u32 n_buffers)
90 ASSERT (n_buffers <= ring_size);
92 if (PREDICT_TRUE (start + n_buffers <= ring_size))
94 clib_memset_u32 (ring + start, ~0, n_buffers);
98 clib_memset_u32 (ring + start, ~0, ring_size - start);
99 clib_memset_u32 (ring, ~0, n_buffers - (ring_size - start));
103 static_always_inline void
104 virtio_free_used_device_desc (vlib_main_t * vm, virtio_vring_t * vring,
107 u16 used = vring->desc_in_use;
108 u16 sz = vring->size;
110 u16 last = vring->last_used_idx;
111 u16 n_left = vring->used->idx - last;
112 u16 out_of_order_count = 0;
119 struct vring_used_elem *e = &vring->used->ring[last & mask];
121 slot = n_buffers = e->id;
123 while (e->id == (n_buffers & mask))
130 e = &vring->used->ring[last & mask];
132 vlib_buffer_free_from_ring (vm, vring->buffers, slot,
133 sz, (n_buffers - slot));
134 virtio_memset_ring_u32 (vring->buffers, slot, sz, (n_buffers - slot));
135 used -= (n_buffers - slot);
139 vlib_buffer_free (vm, &vring->buffers[e->id], 1);
140 vring->buffers[e->id] = ~0;
144 out_of_order_count++;
145 vring->flags |= VRING_TX_OUT_OF_ORDER;
150 * Some vhost-backends give buffers back in out-of-order fashion in used ring.
151 * It impacts the overall virtio-performance.
153 if (out_of_order_count)
154 vlib_error_count (vm, node_index, VIRTIO_TX_ERROR_OUT_OF_ORDER,
157 vring->desc_in_use = used;
158 vring->last_used_idx = last;
161 static_always_inline void
162 set_checksum_offsets (vlib_buffer_t * b, struct virtio_net_hdr_v1 *hdr)
164 if (b->flags & VNET_BUFFER_F_IS_IP4)
167 gso_header_offset_t gho = vnet_gso_header_offset_parser (b, 0);
168 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
169 hdr->csum_start = gho.l4_hdr_offset; // 0x22;
170 if (b->flags & VNET_BUFFER_F_OFFLOAD_TCP_CKSUM)
172 hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum);
174 else if (b->flags & VNET_BUFFER_F_OFFLOAD_UDP_CKSUM)
176 hdr->csum_offset = STRUCT_OFFSET_OF (udp_header_t, checksum);
180 * virtio devices do not support IP4 checksum offload. So driver takes care
181 * of it while doing tx.
184 (ip4_header_t *) (vlib_buffer_get_current (b) + gho.l3_hdr_offset);
185 if (b->flags & VNET_BUFFER_F_OFFLOAD_IP_CKSUM)
186 ip4->checksum = ip4_header_checksum (ip4);
188 else if (b->flags & VNET_BUFFER_F_IS_IP6)
190 gso_header_offset_t gho = vnet_gso_header_offset_parser (b, 1);
191 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
192 hdr->csum_start = gho.l4_hdr_offset; // 0x36;
193 if (b->flags & VNET_BUFFER_F_OFFLOAD_TCP_CKSUM)
195 hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum);
197 else if (b->flags & VNET_BUFFER_F_OFFLOAD_UDP_CKSUM)
199 hdr->csum_offset = STRUCT_OFFSET_OF (udp_header_t, checksum);
204 static_always_inline void
205 set_gso_offsets (vlib_buffer_t * b, struct virtio_net_hdr_v1 *hdr)
207 if (b->flags & VNET_BUFFER_F_IS_IP4)
210 gso_header_offset_t gho = vnet_gso_header_offset_parser (b, 0);
211 hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
212 hdr->gso_size = vnet_buffer2 (b)->gso_size;
213 hdr->hdr_len = gho.l4_hdr_offset + gho.l4_hdr_sz;
214 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
215 hdr->csum_start = gho.l4_hdr_offset; // 0x22;
216 hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum);
218 (ip4_header_t *) (vlib_buffer_get_current (b) + gho.l3_hdr_offset);
220 * virtio devices do not support IP4 checksum offload. So driver takes care
221 * of it while doing tx.
223 if (b->flags & VNET_BUFFER_F_OFFLOAD_IP_CKSUM)
224 ip4->checksum = ip4_header_checksum (ip4);
226 else if (b->flags & VNET_BUFFER_F_IS_IP6)
228 gso_header_offset_t gho = vnet_gso_header_offset_parser (b, 1);
229 hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
230 hdr->gso_size = vnet_buffer2 (b)->gso_size;
231 hdr->hdr_len = gho.l4_hdr_offset + gho.l4_hdr_sz;
232 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
233 hdr->csum_start = gho.l4_hdr_offset; // 0x36;
234 hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum);
238 static_always_inline u16
239 add_buffer_to_slot (vlib_main_t * vm, virtio_if_t * vif,
240 virtio_vring_t * vring, u32 bi, u16 avail, u16 next,
241 u16 mask, int do_gso, int csum_offload, uword node_index)
244 int hdr_sz = vif->virtio_net_hdr_sz;
245 struct vring_desc *d;
246 d = &vring->desc[next];
247 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
248 struct virtio_net_hdr_v1 *hdr = vlib_buffer_get_current (b) - hdr_sz;
250 clib_memset (hdr, 0, hdr_sz);
252 if (b->flags & VNET_BUFFER_F_GSO)
255 set_gso_offsets (b, hdr);
258 virtio_interface_drop_inline (vm, node_index, &bi, 1,
259 VIRTIO_TX_ERROR_GSO_PACKET_DROP);
263 else if (b->flags & (VNET_BUFFER_F_OFFLOAD_TCP_CKSUM |
264 VNET_BUFFER_F_OFFLOAD_UDP_CKSUM))
267 set_checksum_offsets (b, hdr);
270 virtio_interface_drop_inline (vm, node_index, &bi, 1,
271 VIRTIO_TX_ERROR_CSUM_OFFLOAD_PACKET_DROP);
276 if (PREDICT_TRUE ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0))
279 ((vif->type == VIRTIO_IF_TYPE_PCI) ? vlib_buffer_get_current_pa (vm,
281 pointer_to_uword (vlib_buffer_get_current (b))) - hdr_sz;
282 d->len = b->current_length + hdr_sz;
288 * We are using single vlib_buffer_t for indirect descriptor(s)
289 * chain. Single descriptor is 16 bytes and vlib_buffer_t
290 * has 2048 bytes space. So maximum long chain can have 128
291 * (=2048/16) indirect descriptors.
292 * It can easily support 65535 bytes of Jumbo frames with
293 * each data buffer size of 512 bytes minimum.
295 u32 indirect_buffer = 0;
296 if (PREDICT_FALSE (vlib_buffer_alloc (vm, &indirect_buffer, 1) == 0))
298 virtio_interface_drop_inline (vm, node_index, &bi, 1,
299 VIRTIO_TX_ERROR_INDIRECT_DESC_ALLOC_FAILED);
303 vlib_buffer_t *indirect_desc = vlib_get_buffer (vm, indirect_buffer);
304 indirect_desc->current_data = 0;
305 indirect_desc->flags |= VLIB_BUFFER_NEXT_PRESENT;
306 indirect_desc->next_buffer = bi;
307 bi = indirect_buffer;
309 struct vring_desc *id =
310 (struct vring_desc *) vlib_buffer_get_current (indirect_desc);
312 if (vif->type == VIRTIO_IF_TYPE_PCI)
314 d->addr = vlib_physmem_get_pa (vm, id);
315 id->addr = vlib_buffer_get_current_pa (vm, b) - hdr_sz;
318 * If VIRTIO_F_ANY_LAYOUT is not negotiated, then virtio_net_hdr
319 * should be presented in separate descriptor and data will start
320 * from next descriptor.
323 (vif->features & VIRTIO_FEATURE (VIRTIO_F_ANY_LAYOUT)))
324 id->len = b->current_length + hdr_sz;
328 id->flags = VRING_DESC_F_NEXT;
332 id->addr = vlib_buffer_get_current_pa (vm, b);
333 id->len = b->current_length;
335 while (b->flags & VLIB_BUFFER_NEXT_PRESENT)
337 id->flags = VRING_DESC_F_NEXT;
341 b = vlib_get_buffer (vm, b->next_buffer);
342 id->addr = vlib_buffer_get_current_pa (vm, b);
343 id->len = b->current_length;
346 else /* VIRTIO_IF_TYPE_TAP */
348 d->addr = pointer_to_uword (id);
349 /* first buffer in chain */
350 id->addr = pointer_to_uword (vlib_buffer_get_current (b)) - hdr_sz;
351 id->len = b->current_length + hdr_sz;
353 while (b->flags & VLIB_BUFFER_NEXT_PRESENT)
355 id->flags = VRING_DESC_F_NEXT;
359 b = vlib_get_buffer (vm, b->next_buffer);
360 id->addr = pointer_to_uword (vlib_buffer_get_current (b));
361 id->len = b->current_length;
366 d->len = count * sizeof (struct vring_desc);
367 d->flags = VRING_DESC_F_INDIRECT;
369 vring->buffers[next] = bi;
370 vring->avail->ring[avail & mask] = next;
375 static_always_inline void
376 virtio_find_free_desc (virtio_vring_t * vring, u16 size, u16 mask,
377 u16 req, u16 next, u32 * first_free_desc_index,
378 u16 * free_desc_count)
381 /* next is used as hint: from where to start looking */
382 for (u16 i = 0; i < size; i++, next++)
384 if (vring->buffers[next & mask] == ~0)
386 if (*first_free_desc_index == ~0)
388 *first_free_desc_index = (next & mask);
390 (*free_desc_count)++;
397 if (start + *free_desc_count == i)
399 (*free_desc_count)++;
411 static_always_inline uword
412 virtio_interface_tx_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
413 vlib_frame_t * frame, virtio_if_t * vif,
414 int do_gso, int csum_offload)
416 u16 n_left = frame->n_vectors;
417 virtio_vring_t *vring;
418 u16 qid = vm->thread_index % vif->num_txqs;
419 vring = vec_elt_at_index (vif->txq_vrings, qid);
420 u16 used, next, avail;
421 u16 sz = vring->size;
424 u32 *buffers = vlib_frame_vector_args (frame);
426 clib_spinlock_lock_if_init (&vring->lockp);
428 if ((vring->used->flags & VIRTIO_RING_FLAG_MASK_INT) == 0 &&
429 (vring->last_kick_avail_idx != vring->avail->idx))
430 virtio_kick (vm, vring, vif);
433 /* free consumed buffers */
434 virtio_free_used_device_desc (vm, vring, node->node_index);
436 used = vring->desc_in_use;
437 next = vring->desc_next;
438 avail = vring->avail->idx;
440 u16 free_desc_count = 0;
442 if (PREDICT_FALSE (vring->flags & VRING_TX_OUT_OF_ORDER))
444 u32 first_free_desc_index = ~0;
446 virtio_find_free_desc (vring, sz, mask, n_left, next,
447 &first_free_desc_index, &free_desc_count);
450 next = first_free_desc_index;
453 free_desc_count = sz - used;
455 while (n_left && free_desc_count)
459 add_buffer_to_slot (vm, vif, vring, buffers[0], avail, next, mask,
460 do_gso, csum_offload, node->node_index);
462 if (PREDICT_FALSE (n_added == 0))
470 next = (next + n_added) & mask;
477 if (n_left != frame->n_vectors)
479 CLIB_MEMORY_STORE_BARRIER ();
480 vring->avail->idx = avail;
481 vring->desc_next = next;
482 vring->desc_in_use = used;
483 if ((vring->used->flags & VIRTIO_RING_FLAG_MASK_INT) == 0)
484 virtio_kick (vm, vring, vif);
492 virtio_interface_drop_inline (vm, node->node_index, buffers, n_left,
493 VIRTIO_TX_ERROR_NO_FREE_SLOTS);
496 clib_spinlock_unlock_if_init (&vring->lockp);
498 return frame->n_vectors - n_left;
501 VNET_DEVICE_CLASS_TX_FN (virtio_device_class) (vlib_main_t * vm,
502 vlib_node_runtime_t * node,
503 vlib_frame_t * frame)
505 vnet_main_t *vnm = vnet_get_main ();
506 virtio_main_t *nm = &virtio_main;
507 vnet_interface_output_runtime_t *rund = (void *) node->runtime_data;
508 virtio_if_t *vif = pool_elt_at_index (nm->interfaces, rund->dev_instance);
509 vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, vif->hw_if_index);
511 if (hw->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_GSO)
512 return virtio_interface_tx_inline (vm, node, frame, vif, 1 /* do_gso */ ,
514 else if (hw->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_TX_L4_CKSUM_OFFLOAD)
515 return virtio_interface_tx_inline (vm, node, frame, vif,
516 0 /* no do_gso */ , 1);
518 return virtio_interface_tx_inline (vm, node, frame, vif,
519 0 /* no do_gso */ , 0);
523 virtio_set_interface_next_node (vnet_main_t * vnm, u32 hw_if_index,
526 virtio_main_t *apm = &virtio_main;
527 vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
528 virtio_if_t *vif = pool_elt_at_index (apm->interfaces, hw->dev_instance);
530 /* Shut off redirection */
531 if (node_index == ~0)
533 vif->per_interface_next_index = node_index;
537 vif->per_interface_next_index =
538 vlib_node_add_next (vlib_get_main (), virtio_input_node.index,
543 virtio_clear_hw_interface_counters (u32 instance)
545 /* Nothing for now */
548 static clib_error_t *
549 virtio_interface_rx_mode_change (vnet_main_t * vnm, u32 hw_if_index, u32 qid,
550 vnet_hw_interface_rx_mode mode)
552 virtio_main_t *mm = &virtio_main;
553 vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
554 virtio_if_t *vif = pool_elt_at_index (mm->interfaces, hw->dev_instance);
555 virtio_vring_t *vring = vec_elt_at_index (vif->rxq_vrings, qid);
557 if (vif->type == VIRTIO_IF_TYPE_PCI && !(vif->support_int_mode))
559 vring->avail->flags |= VIRTIO_RING_FLAG_MASK_INT;
560 return clib_error_return (0, "interrupt mode is not supported");
563 if (mode == VNET_HW_INTERFACE_RX_MODE_POLLING)
564 vring->avail->flags |= VIRTIO_RING_FLAG_MASK_INT;
566 vring->avail->flags &= ~VIRTIO_RING_FLAG_MASK_INT;
571 static clib_error_t *
572 virtio_interface_admin_up_down (vnet_main_t * vnm, u32 hw_if_index, u32 flags)
574 virtio_main_t *mm = &virtio_main;
575 vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
576 virtio_if_t *vif = pool_elt_at_index (mm->interfaces, hw->dev_instance);
578 if (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP)
580 vif->flags |= VIRTIO_IF_FLAG_ADMIN_UP;
581 vnet_hw_interface_set_flags (vnm, vif->hw_if_index,
582 VNET_HW_INTERFACE_FLAG_LINK_UP);
586 vif->flags &= ~VIRTIO_IF_FLAG_ADMIN_UP;
587 vnet_hw_interface_set_flags (vnm, vif->hw_if_index, 0);
592 static clib_error_t *
593 virtio_subif_add_del_function (vnet_main_t * vnm,
595 struct vnet_sw_interface_t *st, int is_add)
597 /* Nothing for now */
602 VNET_DEVICE_CLASS (virtio_device_class) = {
604 .format_device_name = format_virtio_device_name,
605 .format_device = format_virtio_device,
606 .format_tx_trace = format_virtio_tx_trace,
607 .tx_function_n_errors = VIRTIO_TX_N_ERROR,
608 .tx_function_error_strings = virtio_tx_func_error_strings,
609 .rx_redirect_to_node = virtio_set_interface_next_node,
610 .clear_counters = virtio_clear_hw_interface_counters,
611 .admin_up_down_function = virtio_interface_admin_up_down,
612 .subif_add_del_function = virtio_subif_add_del_function,
613 .rx_mode_change_function = virtio_interface_rx_mode_change,
618 * fd.io coding-style-patch-verification: ON
621 * eval: (c-set-style "gnu")