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 _(NO_TX_QUEUES, "no tx queues") \
37 _(OUT_OF_ORDER, "out-of-order buffers in used ring")
41 #define _(f,s) VIRTIO_TX_ERROR_##f,
42 foreach_virtio_tx_func_error
45 } virtio_tx_func_error_t;
47 static char *virtio_tx_func_error_strings[] = {
49 foreach_virtio_tx_func_error
54 format_virtio_device (u8 * s, va_list * args)
56 u32 dev_instance = va_arg (*args, u32);
57 int verbose = va_arg (*args, int);
58 u32 indent = format_get_indent (s);
60 s = format (s, "VIRTIO interface");
63 s = format (s, "\n%U instance %u", format_white_space, indent + 2,
70 format_virtio_tx_trace (u8 * s, va_list * args)
72 s = format (s, "Unimplemented...");
76 static_always_inline void
77 virtio_memset_ring_u32 (u32 * ring, u32 start, u32 ring_size, u32 n_buffers)
79 ASSERT (n_buffers <= ring_size);
81 if (PREDICT_TRUE (start + n_buffers <= ring_size))
83 clib_memset_u32 (ring + start, ~0, n_buffers);
87 clib_memset_u32 (ring + start, ~0, ring_size - start);
88 clib_memset_u32 (ring, ~0, n_buffers - (ring_size - start));
92 static_always_inline void
93 virtio_free_used_device_desc (vlib_main_t * vm, virtio_vring_t * vring,
96 u16 used = vring->desc_in_use;
99 u16 last = vring->last_used_idx;
100 u16 n_left = vring->used->idx - last;
101 u16 out_of_order_count = 0;
108 struct vring_used_elem *e = &vring->used->ring[last & mask];
110 slot = n_buffers = e->id;
112 while (e->id == (n_buffers & mask))
119 e = &vring->used->ring[last & mask];
121 vlib_buffer_free_from_ring (vm, vring->buffers, slot,
122 sz, (n_buffers - slot));
123 virtio_memset_ring_u32 (vring->buffers, slot, sz, (n_buffers - slot));
124 used -= (n_buffers - slot);
128 vlib_buffer_free (vm, &vring->buffers[e->id], 1);
129 vring->buffers[e->id] = ~0;
133 out_of_order_count++;
134 vring->flags |= VRING_TX_OUT_OF_ORDER;
139 * Some vhost-backends give buffers back in out-of-order fashion in used ring.
140 * It impacts the overall virtio-performance.
142 if (out_of_order_count)
143 vlib_error_count (vm, node_index, VIRTIO_TX_ERROR_OUT_OF_ORDER,
146 vring->desc_in_use = used;
147 vring->last_used_idx = last;
150 static_always_inline void
151 set_checksum_offsets (vlib_main_t * vm, virtio_if_t * vif, vlib_buffer_t * b,
152 struct virtio_net_hdr_v1 *hdr)
154 if (b->flags & VNET_BUFFER_F_IS_IP4)
157 gso_header_offset_t gho = vnet_gso_header_offset_parser (b, 0);
158 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
159 hdr->csum_start = gho.l4_hdr_offset; // 0x22;
160 if (b->flags & VNET_BUFFER_F_OFFLOAD_TCP_CKSUM)
161 hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum);
162 else if (b->flags & VNET_BUFFER_F_OFFLOAD_UDP_CKSUM)
163 hdr->csum_offset = STRUCT_OFFSET_OF (udp_header_t, checksum);
166 * virtio devices do not support IP4 checksum offload. So driver takes care
167 * of it while doing tx.
170 (ip4_header_t *) (vlib_buffer_get_current (b) + gho.l3_hdr_offset);
171 if (b->flags & VNET_BUFFER_F_OFFLOAD_IP_CKSUM)
172 ip4->checksum = ip4_header_checksum (ip4);
174 else if (b->flags & VNET_BUFFER_F_IS_IP6)
176 gso_header_offset_t gho = vnet_gso_header_offset_parser (b, 1);
177 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
178 hdr->csum_start = gho.l4_hdr_offset; // 0x36;
179 if (b->flags & VNET_BUFFER_F_OFFLOAD_TCP_CKSUM)
180 hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum);
181 else if (b->flags & VNET_BUFFER_F_OFFLOAD_UDP_CKSUM)
182 hdr->csum_offset = STRUCT_OFFSET_OF (udp_header_t, checksum);
186 static_always_inline u16
187 add_buffer_to_slot (vlib_main_t * vm, virtio_if_t * vif,
188 virtio_vring_t * vring, u32 bi, u16 avail, u16 next,
189 u16 mask, int do_gso, int csum_offload)
192 int hdr_sz = vif->virtio_net_hdr_sz;
193 struct vring_desc *d;
194 d = &vring->desc[next];
195 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
196 struct virtio_net_hdr_v1 *hdr = vlib_buffer_get_current (b) - hdr_sz;
198 clib_memset (hdr, 0, hdr_sz);
200 if (do_gso && (b->flags & VNET_BUFFER_F_GSO))
202 if (b->flags & VNET_BUFFER_F_IS_IP4)
205 gso_header_offset_t gho = vnet_gso_header_offset_parser (b, 0);
206 hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
207 hdr->gso_size = vnet_buffer2 (b)->gso_size;
208 hdr->hdr_len = gho.l4_hdr_offset + gho.l4_hdr_sz;
209 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
210 hdr->csum_start = gho.l4_hdr_offset; // 0x22;
211 hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum);
213 (ip4_header_t *) (vlib_buffer_get_current (b) +
216 * virtio devices do not support IP4 checksum offload. So driver takes care
217 * of it while doing tx.
219 if (b->flags & VNET_BUFFER_F_OFFLOAD_IP_CKSUM)
220 ip4->checksum = ip4_header_checksum (ip4);
222 else if (b->flags & VNET_BUFFER_F_IS_IP6)
224 gso_header_offset_t gho = vnet_gso_header_offset_parser (b, 1);
225 hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
226 hdr->gso_size = vnet_buffer2 (b)->gso_size;
227 hdr->hdr_len = gho.l4_hdr_offset + gho.l4_hdr_sz;
228 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
229 hdr->csum_start = gho.l4_hdr_offset; // 0x36;
230 hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum);
233 else if (csum_offload
234 && (b->flags & (VNET_BUFFER_F_OFFLOAD_TCP_CKSUM |
235 VNET_BUFFER_F_OFFLOAD_UDP_CKSUM)))
237 set_checksum_offsets (vm, vif, b, hdr);
240 if (PREDICT_TRUE ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0))
243 ((vif->type == VIRTIO_IF_TYPE_PCI) ? vlib_buffer_get_current_pa (vm,
245 pointer_to_uword (vlib_buffer_get_current (b))) - hdr_sz;
246 d->len = b->current_length + hdr_sz;
252 * We are using single vlib_buffer_t for indirect descriptor(s)
253 * chain. Single descriptor is 16 bytes and vlib_buffer_t
254 * has 2048 bytes space. So maximum long chain can have 128
255 * (=2048/16) indirect descriptors.
256 * It can easily support 65535 bytes of Jumbo frames with
257 * each data buffer size of 512 bytes minimum.
259 u32 indirect_buffer = 0;
260 if (PREDICT_FALSE (vlib_buffer_alloc (vm, &indirect_buffer, 1) == 0))
263 vlib_buffer_t *indirect_desc = vlib_get_buffer (vm, indirect_buffer);
264 indirect_desc->current_data = 0;
265 indirect_desc->flags |= VLIB_BUFFER_NEXT_PRESENT;
266 indirect_desc->next_buffer = bi;
267 bi = indirect_buffer;
269 struct vring_desc *id =
270 (struct vring_desc *) vlib_buffer_get_current (indirect_desc);
272 if (vif->type == VIRTIO_IF_TYPE_PCI)
274 d->addr = vlib_physmem_get_pa (vm, id);
275 id->addr = vlib_buffer_get_current_pa (vm, b) - hdr_sz;
278 * If VIRTIO_F_ANY_LAYOUT is not negotiated, then virtio_net_hdr
279 * should be presented in separate descriptor and data will start
280 * from next descriptor.
283 (vif->features & VIRTIO_FEATURE (VIRTIO_F_ANY_LAYOUT)))
284 id->len = b->current_length + hdr_sz;
288 id->flags = VRING_DESC_F_NEXT;
292 id->addr = vlib_buffer_get_current_pa (vm, b);
293 id->len = b->current_length;
295 while (b->flags & VLIB_BUFFER_NEXT_PRESENT)
297 id->flags = VRING_DESC_F_NEXT;
301 b = vlib_get_buffer (vm, b->next_buffer);
302 id->addr = vlib_buffer_get_current_pa (vm, b);
303 id->len = b->current_length;
306 else /* VIRTIO_IF_TYPE_TAP */
308 d->addr = pointer_to_uword (id);
309 /* first buffer in chain */
310 id->addr = pointer_to_uword (vlib_buffer_get_current (b)) - hdr_sz;
311 id->len = b->current_length + hdr_sz;
313 while (b->flags & VLIB_BUFFER_NEXT_PRESENT)
315 id->flags = VRING_DESC_F_NEXT;
319 b = vlib_get_buffer (vm, b->next_buffer);
320 id->addr = pointer_to_uword (vlib_buffer_get_current (b));
321 id->len = b->current_length;
326 d->len = count * sizeof (struct vring_desc);
327 d->flags = VRING_DESC_F_INDIRECT;
329 vring->buffers[next] = bi;
330 vring->avail->ring[avail & mask] = next;
335 static_always_inline void
336 virtio_find_free_desc (virtio_vring_t * vring, u16 size, u16 mask,
337 u16 req, u16 next, u32 * first_free_desc_index,
338 u16 * free_desc_count)
341 /* next is used as hint: from where to start looking */
342 for (u16 i = 0; i < size; i++, next++)
344 if (vring->buffers[next & mask] == ~0)
346 if (*first_free_desc_index == ~0)
348 *first_free_desc_index = (next & mask);
350 (*free_desc_count)++;
357 if (start + *free_desc_count == i)
359 (*free_desc_count)++;
371 static_always_inline uword
372 virtio_interface_tx_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
373 vlib_frame_t * frame, virtio_if_t * vif,
374 int do_gso, int csum_offload)
376 u16 n_left = frame->n_vectors;
377 virtio_vring_t *vring;
378 u16 qid = vm->thread_index % vif->num_txqs;
379 vring = vec_elt_at_index (vif->txq_vrings, qid);
380 u16 used, next, avail;
381 u16 sz = vring->size;
384 u32 *buffers = vlib_frame_vector_args (frame);
386 clib_spinlock_lock_if_init (&vring->lockp);
388 if ((vring->used->flags & VIRTIO_RING_FLAG_MASK_INT) == 0 &&
389 (vring->last_kick_avail_idx != vring->avail->idx))
390 virtio_kick (vm, vring, vif);
393 /* free consumed buffers */
394 virtio_free_used_device_desc (vm, vring, node->node_index);
396 used = vring->desc_in_use;
397 next = vring->desc_next;
398 avail = vring->avail->idx;
400 u16 free_desc_count = 0;
402 if (PREDICT_FALSE (vring->flags & VRING_TX_OUT_OF_ORDER))
404 u32 first_free_desc_index = ~0;
406 virtio_find_free_desc (vring, sz, mask, n_left, next,
407 &first_free_desc_index, &free_desc_count);
410 next = first_free_desc_index;
413 free_desc_count = sz - used;
415 while (n_left && free_desc_count)
419 add_buffer_to_slot (vm, vif, vring, buffers[0], avail, next, mask,
420 do_gso, csum_offload);
424 next = (next + n_added) & mask;
431 if (n_left != frame->n_vectors)
433 CLIB_MEMORY_STORE_BARRIER ();
434 vring->avail->idx = avail;
435 vring->desc_next = next;
436 vring->desc_in_use = used;
437 if ((vring->used->flags & VIRTIO_RING_FLAG_MASK_INT) == 0)
438 virtio_kick (vm, vring, vif);
446 vlib_error_count (vm, node->node_index, VIRTIO_TX_ERROR_NO_FREE_SLOTS,
448 vlib_buffer_free (vm, buffers, n_left);
451 clib_spinlock_unlock_if_init (&vring->lockp);
453 return frame->n_vectors - n_left;
456 VNET_DEVICE_CLASS_TX_FN (virtio_device_class) (vlib_main_t * vm,
457 vlib_node_runtime_t * node,
458 vlib_frame_t * frame)
460 vnet_main_t *vnm = vnet_get_main ();
461 virtio_main_t *nm = &virtio_main;
462 vnet_interface_output_runtime_t *rund = (void *) node->runtime_data;
463 virtio_if_t *vif = pool_elt_at_index (nm->interfaces, rund->dev_instance);
464 vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, vif->hw_if_index);
466 if (hw->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_GSO)
467 return virtio_interface_tx_inline (vm, node, frame, vif, 1 /* do_gso */ ,
469 else if (hw->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_TX_L4_CKSUM_OFFLOAD)
470 return virtio_interface_tx_inline (vm, node, frame, vif,
471 0 /* no do_gso */ , 1);
473 return virtio_interface_tx_inline (vm, node, frame, vif,
474 0 /* no do_gso */ , 0);
478 virtio_set_interface_next_node (vnet_main_t * vnm, u32 hw_if_index,
481 virtio_main_t *apm = &virtio_main;
482 vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
483 virtio_if_t *vif = pool_elt_at_index (apm->interfaces, hw->dev_instance);
485 /* Shut off redirection */
486 if (node_index == ~0)
488 vif->per_interface_next_index = node_index;
492 vif->per_interface_next_index =
493 vlib_node_add_next (vlib_get_main (), virtio_input_node.index,
498 virtio_clear_hw_interface_counters (u32 instance)
500 /* Nothing for now */
503 static clib_error_t *
504 virtio_interface_rx_mode_change (vnet_main_t * vnm, u32 hw_if_index, u32 qid,
505 vnet_hw_interface_rx_mode mode)
507 virtio_main_t *mm = &virtio_main;
508 vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
509 virtio_if_t *vif = pool_elt_at_index (mm->interfaces, hw->dev_instance);
510 virtio_vring_t *vring = vec_elt_at_index (vif->rxq_vrings, qid);
512 if (vif->type == VIRTIO_IF_TYPE_PCI && !(vif->support_int_mode))
514 vring->avail->flags |= VIRTIO_RING_FLAG_MASK_INT;
515 return clib_error_return (0, "interrupt mode is not supported");
518 if (mode == VNET_HW_INTERFACE_RX_MODE_POLLING)
519 vring->avail->flags |= VIRTIO_RING_FLAG_MASK_INT;
521 vring->avail->flags &= ~VIRTIO_RING_FLAG_MASK_INT;
526 static clib_error_t *
527 virtio_interface_admin_up_down (vnet_main_t * vnm, u32 hw_if_index, u32 flags)
529 virtio_main_t *mm = &virtio_main;
530 vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
531 virtio_if_t *vif = pool_elt_at_index (mm->interfaces, hw->dev_instance);
533 if (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP)
534 vif->flags |= VIRTIO_IF_FLAG_ADMIN_UP;
536 vif->flags &= ~VIRTIO_IF_FLAG_ADMIN_UP;
541 static clib_error_t *
542 virtio_subif_add_del_function (vnet_main_t * vnm,
544 struct vnet_sw_interface_t *st, int is_add)
546 /* Nothing for now */
551 VNET_DEVICE_CLASS (virtio_device_class) = {
553 .format_device_name = format_virtio_device_name,
554 .format_device = format_virtio_device,
555 .format_tx_trace = format_virtio_tx_trace,
556 .tx_function_n_errors = VIRTIO_TX_N_ERROR,
557 .tx_function_error_strings = virtio_tx_func_error_strings,
558 .rx_redirect_to_node = virtio_set_interface_next_node,
559 .clear_counters = virtio_clear_hw_interface_counters,
560 .admin_up_down_function = virtio_interface_admin_up_down,
561 .subif_add_del_function = virtio_subif_add_del_function,
562 .rx_mode_change_function = virtio_interface_rx_mode_change,
567 * fd.io coding-style-patch-verification: ON
570 * eval: (c-set-style "gnu")