FD.io VPP  v19.08.3-2-gbabecb413
Vector Packet Processing
node.c
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1 /*
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:
7  *
8  * http://www.apache.org/licenses/LICENSE-2.0
9  *
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  *------------------------------------------------------------------
16  */
17 
18 #include <sys/types.h>
19 #include <sys/stat.h>
20 #include <fcntl.h>
21 #include <net/if.h>
22 #include <linux/if_tun.h>
23 #include <sys/ioctl.h>
24 #include <sys/eventfd.h>
25 
26 #include <vlib/vlib.h>
27 #include <vlib/unix/unix.h>
28 #include <vnet/ethernet/ethernet.h>
29 #include <vnet/devices/devices.h>
30 #include <vnet/feature/feature.h>
31 #include <vnet/ip/ip4_packet.h>
32 #include <vnet/ip/ip6_packet.h>
33 #include <vnet/udp/udp_packet.h>
35 
36 
37 #define foreach_virtio_input_error \
38  _(UNKNOWN, "unknown")
39 
40 typedef enum
41 {
42 #define _(f,s) VIRTIO_INPUT_ERROR_##f,
44 #undef _
47 
48 static char *virtio_input_error_strings[] = {
49 #define _(n,s) s,
51 #undef _
52 };
53 
54 typedef struct
55 {
60  struct virtio_net_hdr_v1 hdr;
62 
63 static u8 *
64 format_virtio_input_trace (u8 * s, va_list * args)
65 {
66  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
67  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
68  virtio_input_trace_t *t = va_arg (*args, virtio_input_trace_t *);
69  u32 indent = format_get_indent (s);
70 
71  s = format (s, "virtio: hw_if_index %d next-index %d vring %u len %u",
72  t->hw_if_index, t->next_index, t->ring, t->len);
73  s = format (s, "\n%Uhdr: flags 0x%02x gso_type 0x%02x hdr_len %u "
74  "gso_size %u csum_start %u csum_offset %u num_buffers %u",
75  format_white_space, indent + 2,
76  t->hdr.flags, t->hdr.gso_type, t->hdr.hdr_len, t->hdr.gso_size,
77  t->hdr.csum_start, t->hdr.csum_offset, t->hdr.num_buffers);
78  return s;
79 }
80 
83  virtio_vring_t * vring, const int hdr_sz)
84 {
85  u16 used, next, avail, n_slots;
86  u16 sz = vring->size;
87  u16 mask = sz - 1;
88 
89 more:
90  used = vring->desc_in_use;
91 
92  if (sz - used < sz / 8)
93  return;
94 
95  /* deliver free buffers in chunks of 64 */
96  n_slots = clib_min (sz - used, 64);
97 
98  next = vring->desc_next;
99  avail = vring->avail->idx;
100  n_slots =
102  vring->size, n_slots,
103  vring->buffer_pool_index);
104 
105  if (n_slots == 0)
106  return;
107 
108  while (n_slots)
109  {
110  struct vring_desc *d = &vring->desc[next];;
111  vlib_buffer_t *b = vlib_get_buffer (vm, vring->buffers[next]);
112  /*
113  * current_data may not be initialized with 0 and may contain
114  * previous offset. Here we want to make sure, it should be 0
115  * initialized.
116  */
117  b->current_data = 0;
118  b->current_data -= hdr_sz;
119  memset (vlib_buffer_get_current (b), 0, hdr_sz);
120  d->addr =
122  b) :
124  d->len = vlib_buffer_get_default_data_size (vm) + hdr_sz;
125  d->flags = VRING_DESC_F_WRITE;
126  vring->avail->ring[avail & mask] = next;
127  avail++;
128  next = (next + 1) & mask;
129  n_slots--;
130  used++;
131  }
133  vring->avail->idx = avail;
134  vring->desc_next = next;
135  vring->desc_in_use = used;
136 
137  if ((vring->used->flags & VIRTIO_RING_FLAG_MASK_INT) == 0)
138  {
139  virtio_kick (vm, vring, vif);
140  }
141  goto more;
142 }
143 
145 fill_gso_buffer_flags (vlib_buffer_t * b0, struct virtio_net_hdr_v1 *hdr)
146 {
147  u8 l4_proto = 0;
148  u8 l4_hdr_sz = 0;
149  if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM)
150 
151  {
153  u16 ethertype = clib_net_to_host_u16 (eh->type);
154  u16 l2hdr_sz = sizeof (ethernet_header_t);
155 
156  if (ethernet_frame_is_tagged (ethertype))
157  {
158  ethernet_vlan_header_t *vlan = (ethernet_vlan_header_t *) (eh + 1);
159 
160  ethertype = clib_net_to_host_u16 (vlan->type);
161  l2hdr_sz += sizeof (*vlan);
162  if (ethertype == ETHERNET_TYPE_VLAN)
163  {
164  vlan++;
165  ethertype = clib_net_to_host_u16 (vlan->type);
166  l2hdr_sz += sizeof (*vlan);
167  }
168  }
169 
170  vnet_buffer (b0)->l2_hdr_offset = 0;
171  vnet_buffer (b0)->l3_hdr_offset = l2hdr_sz;
172  if (PREDICT_TRUE (ethertype == ETHERNET_TYPE_IP4))
173  {
174  ip4_header_t *ip4 = (ip4_header_t *) (b0->data + l2hdr_sz);
175  vnet_buffer (b0)->l4_hdr_offset = l2hdr_sz + ip4_header_bytes (ip4);
176  l4_proto = ip4->protocol;
177  b0->flags |=
178  (VNET_BUFFER_F_IS_IP4 | VNET_BUFFER_F_L2_HDR_OFFSET_VALID
179  | VNET_BUFFER_F_L3_HDR_OFFSET_VALID |
180  VNET_BUFFER_F_L4_HDR_OFFSET_VALID);
181  b0->flags |= VNET_BUFFER_F_OFFLOAD_IP_CKSUM;
182  }
183  else if (PREDICT_TRUE (ethertype == ETHERNET_TYPE_IP6))
184  {
185  ip6_header_t *ip6 = (ip6_header_t *) (b0->data + l2hdr_sz);
186  /* FIXME IPv6 EH traversal */
187  vnet_buffer (b0)->l4_hdr_offset = l2hdr_sz + sizeof (ip6_header_t);
188  l4_proto = ip6->protocol;
189  b0->flags |=
190  (VNET_BUFFER_F_IS_IP6 | VNET_BUFFER_F_L2_HDR_OFFSET_VALID
191  | VNET_BUFFER_F_L3_HDR_OFFSET_VALID |
192  VNET_BUFFER_F_L4_HDR_OFFSET_VALID);
193  }
194  if (l4_proto == IP_PROTOCOL_TCP)
195  {
196  b0->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
197  tcp_header_t *tcp = (tcp_header_t *) (b0->data +
199  (b0)->l4_hdr_offset);
200  l4_hdr_sz = tcp_header_bytes (tcp);
201  tcp->checksum = 0;
202  }
203  else if (l4_proto == IP_PROTOCOL_UDP)
204  {
205  b0->flags |= VNET_BUFFER_F_OFFLOAD_UDP_CKSUM;
206  udp_header_t *udp = (udp_header_t *) (b0->data +
208  (b0)->l4_hdr_offset);
209  l4_hdr_sz = sizeof (*udp);
210  udp->checksum = 0;
211  }
212  }
213 
214  if (hdr->gso_type == VIRTIO_NET_HDR_GSO_TCPV4)
215  {
216  ASSERT (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM);
217  vnet_buffer2 (b0)->gso_size = hdr->gso_size;
218  vnet_buffer2 (b0)->gso_l4_hdr_sz = l4_hdr_sz;
219  b0->flags |= VNET_BUFFER_F_GSO;
220  b0->flags |= VNET_BUFFER_F_IS_IP4;
221  }
222  if (hdr->gso_type == VIRTIO_NET_HDR_GSO_TCPV6)
223  {
224  ASSERT (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM);
225  vnet_buffer2 (b0)->gso_size = hdr->gso_size;
226  vnet_buffer2 (b0)->gso_l4_hdr_sz = l4_hdr_sz;
227  b0->flags |= VNET_BUFFER_F_GSO;
228  b0->flags |= VNET_BUFFER_F_IS_IP6;
229  }
230 }
231 
232 
235  vlib_frame_t * frame, virtio_if_t * vif, u16 qid,
236  int gso_enabled)
237 {
238  vnet_main_t *vnm = vnet_get_main ();
239  u32 thread_index = vm->thread_index;
240  uword n_trace = vlib_get_trace_count (vm, node);
241  virtio_vring_t *vring = vec_elt_at_index (vif->rxq_vrings, qid);
243  const int hdr_sz = vif->virtio_net_hdr_sz;
244  u32 *to_next = 0;
245  u32 n_rx_packets = 0;
246  u32 n_rx_bytes = 0;
247  u16 mask = vring->size - 1;
248  u16 last = vring->last_used_idx;
249  u16 n_left = vring->used->idx - last;
250 
251  if ((vring->used->flags & VIRTIO_RING_FLAG_MASK_INT) == 0 &&
252  vring->last_kick_avail_idx != vring->avail->idx)
253  virtio_kick (vm, vring, vif);
254 
255  if (n_left == 0)
256  goto refill;
257 
258  while (n_left)
259  {
260  u32 n_left_to_next;
261  u32 next0 = next_index;
262  vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
263 
264  while (n_left && n_left_to_next)
265  {
266  u16 num_buffers = 1;
267  struct vring_used_elem *e = &vring->used->ring[last & mask];
268  struct virtio_net_hdr_v1 *hdr;
269  u16 slot = e->id;
270  u16 len = e->len - hdr_sz;
271  u32 bi0 = vring->buffers[slot];
272  vlib_buffer_t *b0 = vlib_get_buffer (vm, bi0);
273  hdr = vlib_buffer_get_current (b0);
274  if (hdr_sz == sizeof (struct virtio_net_hdr_v1))
275  num_buffers = hdr->num_buffers;
276 
277  b0->current_data += hdr_sz;
278  b0->current_length = len;
280  b0->flags = VLIB_BUFFER_TOTAL_LENGTH_VALID;
281 
282  if (gso_enabled)
283  fill_gso_buffer_flags (b0, hdr);
284 
285  vnet_buffer (b0)->sw_if_index[VLIB_RX] = vif->sw_if_index;
286  vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
287 
288  /* if multisegment packet */
289  if (PREDICT_FALSE (num_buffers > 1))
290  {
291  vlib_buffer_t *pb, *cb;
292  pb = b0;
293  while (num_buffers > 1)
294  {
295  last++;
296  e = &vring->used->ring[last & mask];
297  u32 cbi = vring->buffers[e->id];
298  cb = vlib_get_buffer (vm, cbi);
299 
300  /* current buffer */
301  cb->current_length = e->len;
302 
303  /* previous buffer */
304  pb->next_buffer = cbi;
305  pb->flags |= VLIB_BUFFER_NEXT_PRESENT;
306 
307  /* first buffer */
309 
310  pb = cb;
311  vring->desc_in_use--;
312  num_buffers--;
313  n_left--;
314  }
315  }
316 
317  if (PREDICT_FALSE (vif->per_interface_next_index != ~0))
318  next0 = vif->per_interface_next_index;
319 
320  /* redirect if feature path enabled */
322 
323  /* trace */
325 
326  if (PREDICT_FALSE (n_trace > 0))
327  {
329  vlib_trace_buffer (vm, node, next0, b0,
330  /* follow_chain */ 1);
331  vlib_set_trace_count (vm, node, --n_trace);
332  tr = vlib_add_trace (vm, node, b0, sizeof (*tr));
333  tr->next_index = next0;
334  tr->hw_if_index = vif->hw_if_index;
336  clib_memcpy_fast (&tr->hdr, hdr, hdr_sz);
337  }
338 
339  /* enqueue buffer */
340  to_next[0] = bi0;
341  vring->desc_in_use--;
342  to_next += 1;
343  n_left_to_next--;
344  n_left--;
345  last++;
346 
347  /* enqueue */
348  vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
349  n_left_to_next, bi0, next0);
350 
351  /* next packet */
352  n_rx_packets++;
353  n_rx_bytes += (len + b0->total_length_not_including_first_buffer);
354  }
355  vlib_put_next_frame (vm, node, next_index, n_left_to_next);
356  }
357  vring->last_used_idx = last;
358 
360  + VNET_INTERFACE_COUNTER_RX, thread_index,
361  vif->sw_if_index, n_rx_packets,
362  n_rx_bytes);
363 
364 refill:
365  virtio_refill_vring (vm, vif, vring, hdr_sz);
366 
367  return n_rx_packets;
368 }
369 
371  vlib_node_runtime_t * node,
372  vlib_frame_t * frame)
373 {
374  u32 n_rx = 0;
375  virtio_main_t *nm = &virtio_main;
376  vnet_device_input_runtime_t *rt = (void *) node->runtime_data;
378 
380  {
381  virtio_if_t *vif;
382  vif = vec_elt_at_index (nm->interfaces, dq->dev_instance);
383  if (vif->flags & VIRTIO_IF_FLAG_ADMIN_UP)
384  {
385  if (vif->gso_enabled)
386  n_rx += virtio_device_input_inline (vm, node, frame, vif,
387  dq->queue_id, 1);
388  else
389  n_rx += virtio_device_input_inline (vm, node, frame, vif,
390  dq->queue_id, 0);
391  }
392  }
393 
394  return n_rx;
395 }
396 
397 /* *INDENT-OFF* */
399  .name = "virtio-input",
400  .sibling_of = "device-input",
401  .format_trace = format_virtio_input_trace,
403  .type = VLIB_NODE_TYPE_INPUT,
404  .state = VLIB_NODE_STATE_INTERRUPT,
405  .n_errors = VIRTIO_INPUT_N_ERROR,
406  .error_strings = virtio_input_error_strings,
407 };
408 /* *INDENT-ON* */
409 
410 /*
411  * fd.io coding-style-patch-verification: ON
412  *
413  * Local Variables:
414  * eval: (c-set-style "gnu")
415  * End:
416  */
u32 per_interface_next_index
Definition: virtio.h:151
u32 flags
buffer flags: VLIB_BUFFER_FREE_LIST_INDEX_MASK: bits used to store free list index, VLIB_BUFFER_IS_TRACED: trace this buffer.
Definition: buffer.h:124
struct vring_used * used
Definition: virtio.h:105
static uword vlib_buffer_get_current_pa(vlib_main_t *vm, vlib_buffer_t *b)
Definition: buffer_funcs.h:427
vlib_node_registration_t virtio_input_node
(constructor) VLIB_REGISTER_NODE (virtio_input_node)
Definition: node.c:398
virtio_if_t * interfaces
Definition: virtio.h:193
vnet_device_and_queue_t * devices_and_queues
Definition: devices.h:69
#define clib_min(x, y)
Definition: clib.h:302
#define CLIB_UNUSED(x)
Definition: clib.h:83
static u32 vlib_get_trace_count(vlib_main_t *vm, vlib_node_runtime_t *rt)
Definition: trace_funcs.h:187
static void vlib_increment_combined_counter(vlib_combined_counter_main_t *cm, u32 thread_index, u32 index, u64 n_packets, u64 n_bytes)
Increment a combined counter.
Definition: counter.h:220
vnet_main_t * vnet_get_main(void)
Definition: misc.c:46
#define vnet_buffer2(b)
Definition: buffer.h:424
vnet_interface_main_t interface_main
Definition: vnet.h:56
#define PREDICT_TRUE(x)
Definition: clib.h:113
i16 current_data
signed offset in data[], pre_data[] that we are currently processing.
Definition: buffer.h:110
int gso_enabled
Definition: virtio.h:183
#define CLIB_MEMORY_STORE_BARRIER()
Definition: clib.h:119
u32 dev_instance
Definition: virtio.h:140
#define clib_memcpy_fast(a, b, c)
Definition: string.h:81
#define VLIB_NODE_FLAG_TRACE_SUPPORTED
Definition: node.h:306
u32 thread_index
Definition: main.h:218
u16 current_length
Nbytes between current data and the end of this buffer.
Definition: buffer.h:113
static heap_elt_t * last(heap_header_t *h)
Definition: heap.c:53
static u32 format_get_indent(u8 *s)
Definition: format.h:72
u8 * format(u8 *s, const char *fmt,...)
Definition: format.c:424
#define VLIB_NODE_FN(node)
Definition: node.h:202
static u32 vlib_buffer_alloc_to_ring_from_pool(vlib_main_t *vm, u32 *ring, u32 start, u32 ring_size, u32 n_buffers, u8 buffer_pool_index)
Allocate buffers into ring from specific buffer pool.
Definition: buffer_funcs.h:657
struct _tcp_header tcp_header_t
unsigned char u8
Definition: types.h:56
static void vlib_trace_buffer(vlib_main_t *vm, vlib_node_runtime_t *r, u32 next_index, vlib_buffer_t *b, int follow_chain)
Definition: trace_funcs.h:130
struct vring_avail * avail
Definition: virtio.h:106
#define static_always_inline
Definition: clib.h:100
u32 hw_if_index
Definition: virtio.h:141
static_always_inline void fill_gso_buffer_flags(vlib_buffer_t *b0, struct virtio_net_hdr_v1 *hdr)
Definition: node.c:145
vlib_combined_counter_main_t * combined_sw_if_counters
Definition: interface.h:846
u8 * format_white_space(u8 *s, va_list *va)
Definition: std-formats.c:129
#define vec_elt_at_index(v, i)
Get vector value at index i checking that i is in bounds.
unsigned int u32
Definition: types.h:88
static u8 * format_virtio_input_trace(u8 *s, va_list *args)
Definition: node.c:64
static char * virtio_input_error_strings[]
Definition: node.c:48
#define foreach_virtio_input_error
Definition: node.c:37
virtio_input_error_t
Definition: node.c:40
unsigned short u16
Definition: types.h:57
static void * vlib_buffer_get_current(vlib_buffer_t *b)
Get pointer to current data to process.
Definition: buffer.h:229
#define PREDICT_FALSE(x)
Definition: clib.h:112
u8 buffer_pool_index
Definition: virtio.h:112
#define vlib_validate_buffer_enqueue_x1(vm, node, next_index, to_next, n_left_to_next, bi0, next0)
Finish enqueueing one buffer forward in the graph.
Definition: buffer_node.h:218
#define vlib_get_next_frame(vm, node, next_index, vectors, n_vectors_left)
Get pointer to next frame vector data by (vlib_node_runtime_t, next_index).
Definition: node_funcs.h:338
u8 len
Definition: ip_types.api:90
u16 desc_next
Definition: virtio.h:109
u16 virtio_net_hdr_sz
Definition: virtio.h:144
static_always_inline u32 vlib_buffer_get_default_data_size(vlib_main_t *vm)
Definition: buffer_funcs.h:96
virtio_vring_t * rxq_vrings
Definition: virtio.h:162
u16 last_used_idx
Definition: virtio.h:119
#define VLIB_REGISTER_NODE(x,...)
Definition: node.h:169
vlib_main_t * vm
Definition: buffer.c:323
#define VIRTIO_RING_FLAG_MASK_INT
Definition: virtio.h:99
u8 data[]
Packet data.
Definition: buffer.h:181
u32 flags
Definition: virtio.h:138
u16 last_kick_avail_idx
Definition: virtio.h:120
void vlib_put_next_frame(vlib_main_t *vm, vlib_node_runtime_t *r, u32 next_index, u32 n_vectors_left)
Release pointer to next frame vector data.
Definition: main.c:456
virtio_if_type_t type
Definition: virtio.h:145
#define ASSERT(truth)
static_always_inline int ethernet_frame_is_tagged(u16 type)
Definition: ethernet.h:78
struct virtio_net_hdr_v1 hdr
Definition: node.c:60
static uword pointer_to_uword(const void *p)
Definition: types.h:131
virtio_main_t virtio_main
Definition: virtio.c:37
static void * vlib_add_trace(vlib_main_t *vm, vlib_node_runtime_t *r, vlib_buffer_t *b, u32 n_data_bytes)
Definition: trace_funcs.h:55
#define foreach_device_and_queue(var, vec)
Definition: devices.h:161
Definition: defs.h:47
u32 next_buffer
Next buffer for this linked-list of buffers.
Definition: buffer.h:140
#define VLIB_BUFFER_TRACE_TRAJECTORY_INIT(b)
Definition: buffer.h:489
VLIB buffer representation.
Definition: buffer.h:102
u64 uword
Definition: types.h:112
static_always_inline uword virtio_device_input_inline(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame, virtio_if_t *vif, u16 qid, int gso_enabled)
Definition: node.c:234
u32 * buffers
Definition: virtio.h:118
#define vnet_buffer(b)
Definition: buffer.h:365
u32 sw_if_index
Definition: virtio.h:142
static_always_inline void vnet_feature_start_device_input_x1(u32 sw_if_index, u32 *next0, vlib_buffer_t *b0)
Definition: feature.h:315
static int tcp_header_bytes(tcp_header_t *t)
Definition: tcp_packet.h:93
static_always_inline void virtio_refill_vring(vlib_main_t *vm, virtio_if_t *vif, virtio_vring_t *vring, const int hdr_sz)
Definition: node.c:82
struct vring_desc * desc
Definition: virtio.h:104
static int ip4_header_bytes(const ip4_header_t *i)
Definition: ip4_packet.h:235
static void vlib_set_trace_count(vlib_main_t *vm, vlib_node_runtime_t *rt, u32 count)
Definition: trace_funcs.h:203
u32 total_length_not_including_first_buffer
Only valid for first buffer in chain.
Definition: buffer.h:167
static vlib_buffer_t * vlib_get_buffer(vlib_main_t *vm, u32 buffer_index)
Translate buffer index into buffer pointer.
Definition: buffer_funcs.h:85
u16 desc_in_use
Definition: virtio.h:108
Definition: defs.h:46
static_always_inline void virtio_kick(vlib_main_t *vm, virtio_vring_t *vring, virtio_if_t *vif)
Definition: virtio.h:218