FD.io VPP  v18.10-32-g1161dda
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 <linux/virtio_net.h>
25 #include <linux/vhost.h>
26 #include <sys/eventfd.h>
27 
28 #include <vlib/vlib.h>
29 #include <vlib/unix/unix.h>
30 #include <vnet/ethernet/ethernet.h>
31 #include <vnet/devices/devices.h>
32 #include <vnet/feature/feature.h>
33 #include <vnet/ip/ip4_packet.h>
34 #include <vnet/ip/ip6_packet.h>
36 
37 
38 #define foreach_virtio_input_error \
39  _(UNKNOWN, "unknown")
40 
41 typedef enum
42 {
43 #define _(f,s) TAP_INPUT_ERROR_##f,
45 #undef _
48 
49 static char *virtio_input_error_strings[] = {
50 #define _(n,s) s,
52 #undef _
53 };
54 
55 typedef struct
56 {
61  struct virtio_net_hdr_v1 hdr;
63 
64 static u8 *
65 format_virtio_input_trace (u8 * s, va_list * args)
66 {
67  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
68  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
69  virtio_input_trace_t *t = va_arg (*args, virtio_input_trace_t *);
70  u32 indent = format_get_indent (s);
71 
72  s = format (s, "virtio: hw_if_index %d next-index %d vring %u len %u",
73  t->hw_if_index, t->next_index, t->ring, t->len);
74  s = format (s, "\n%Uhdr: flags 0x%02x gso_type 0x%02x hdr_len %u "
75  "gso_size %u csum_start %u csum_offset %u num_buffers %u",
76  format_white_space, indent + 2,
77  t->hdr.flags, t->hdr.gso_type, t->hdr.hdr_len, t->hdr.gso_size,
78  t->hdr.csum_start, t->hdr.csum_offset, t->hdr.num_buffers);
79  return s;
80 }
81 
84 {
85  const int hdr_sz = sizeof (struct virtio_net_hdr_v1);
86  u16 used, next, avail, n_slots;
87  u16 sz = vring->size;
88  u16 mask = sz - 1;
89 
90 more:
91  used = vring->desc_in_use;
92 
93  if (sz - used < sz / 8)
94  return;
95 
96  /* deliver free buffers in chunks of 64 */
97  n_slots = clib_min (sz - used, 64);
98 
99  next = vring->desc_next;
100  avail = vring->avail->idx;
101  n_slots = vlib_buffer_alloc_to_ring (vm, vring->buffers, next, vring->size,
102  n_slots);
103 
104  if (n_slots == 0)
105  return;
106 
107  while (n_slots)
108  {
109  struct vring_desc *d = &vring->desc[next];;
110  vlib_buffer_t *b = vlib_get_buffer (vm, vring->buffers[next]);
111  d->addr = pointer_to_uword (vlib_buffer_get_current (b)) - hdr_sz;
112  d->len = VLIB_BUFFER_DATA_SIZE + hdr_sz;
113  d->flags = VRING_DESC_F_WRITE;
114  vring->avail->ring[avail & mask] = next;
115  avail++;
116  next = (next + 1) & mask;
117  n_slots--;
118  used++;
119  }
121  vring->avail->idx = avail;
122  vring->desc_next = next;
123  vring->desc_in_use = used;
124 
125  if ((vring->used->flags & VIRTIO_RING_FLAG_MASK_INT) == 0)
126  virtio_kick (vring);
127  goto more;
128 }
129 
132  vlib_frame_t * frame, virtio_if_t * vif, u16 qid)
133 {
134  vnet_main_t *vnm = vnet_get_main ();
135  u32 thread_index = vm->thread_index;
136  uword n_trace = vlib_get_trace_count (vm, node);
137  virtio_vring_t *vring = vec_elt_at_index (vif->vrings, 0);
139  const int hdr_sz = sizeof (struct virtio_net_hdr_v1);
140  u32 *to_next = 0;
141  u32 n_rx_packets = 0;
142  u32 n_rx_bytes = 0;
143  u16 mask = vring->size - 1;
144  u16 last = vring->last_used_idx;
145  u16 n_left = vring->used->idx - last;
146 
147  if ((vring->used->flags & VIRTIO_RING_FLAG_MASK_INT) == 0 &&
148  vring->last_kick_avail_idx != vring->avail->idx)
149  virtio_kick (vring);
150 
151  if (n_left == 0)
152  goto refill;
153 
154  while (n_left)
155  {
156  u32 n_left_to_next;
157  u32 next0 = next_index;
158  vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
159 
160  while (n_left && n_left_to_next)
161  {
162  u16 num_buffers;
163  struct vring_used_elem *e = &vring->used->ring[last & mask];
164  struct virtio_net_hdr_v1 *hdr;
165  u16 slot = e->id;
166  u16 len = e->len - hdr_sz;
167  u32 bi0 = vring->buffers[slot];
168  vlib_buffer_t *b0 = vlib_get_buffer (vm, bi0);
169  hdr = vlib_buffer_get_current (b0) - hdr_sz;
170  num_buffers = hdr->num_buffers;
171 
172  b0->current_data = 0;
173  b0->current_length = len;
175  b0->flags = VLIB_BUFFER_TOTAL_LENGTH_VALID;
176  vnet_buffer (b0)->sw_if_index[VLIB_RX] = vif->sw_if_index;
177  vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
178 
179  /* if multisegment packet */
180  if (PREDICT_FALSE (num_buffers > 1))
181  {
182  vlib_buffer_t *pb, *cb;
183  pb = b0;
184  while (num_buffers > 1)
185  {
186  last++;
187  e = &vring->used->ring[last & mask];
188  u32 cbi = vring->buffers[e->id];
189  cb = vlib_get_buffer (vm, cbi);
190 
191  /* current buffer */
192  cb->current_data = -hdr_sz;
193  cb->current_length = e->len;
194 
195  /* previous buffer */
196  pb->next_buffer = cbi;
197  pb->flags |= VLIB_BUFFER_NEXT_PRESENT;
198 
199  /* first buffer */
201 
202  pb = cb;
203  vring->desc_in_use--;
204  num_buffers--;
205  n_left--;
206  }
207  }
208 
209  if (PREDICT_FALSE (vif->per_interface_next_index != ~0))
210  next0 = vif->per_interface_next_index;
211  else
212  /* redirect if feature path enabled */
214  /* trace */
216 
217  if (PREDICT_FALSE (n_trace > 0))
218  {
220  vlib_trace_buffer (vm, node, next0, b0,
221  /* follow_chain */ 0);
222  vlib_set_trace_count (vm, node, --n_trace);
223  tr = vlib_add_trace (vm, node, b0, sizeof (*tr));
224  tr->next_index = next0;
225  tr->hw_if_index = vif->hw_if_index;
226  tr->len = len;
227  clib_memcpy (&tr->hdr, hdr, hdr_sz);
228  }
229 
230  /* enqueue buffer */
231  to_next[0] = bi0;
232  vring->desc_in_use--;
233  to_next += 1;
234  n_left_to_next--;
235  n_left--;
236  last++;
237 
238  /* enqueue */
239  vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
240  n_left_to_next, bi0, next0);
241 
242  /* next packet */
243  n_rx_packets++;
244  n_rx_bytes += len;
245  }
246  vlib_put_next_frame (vm, node, next_index, n_left_to_next);
247  }
248  vring->last_used_idx = last;
249 
251  + VNET_INTERFACE_COUNTER_RX, thread_index,
252  vif->hw_if_index, n_rx_packets,
253  n_rx_bytes);
254 
255 refill:
256  virtio_refill_vring (vm, vring);
257 
258  return n_rx_packets;
259 }
260 
261 static uword
263  vlib_frame_t * frame)
264 {
265  u32 n_rx = 0;
266  virtio_main_t *nm = &virtio_main;
267  vnet_device_input_runtime_t *rt = (void *) node->runtime_data;
269 
271  {
272  virtio_if_t *mif;
273  mif = vec_elt_at_index (nm->interfaces, dq->dev_instance);
274  if (mif->flags & VIRTIO_IF_FLAG_ADMIN_UP)
275  {
276  n_rx += virtio_device_input_inline (vm, node, frame, mif,
277  dq->queue_id);
278  }
279  }
280 
281  return n_rx;
282 }
283 
284 /* *INDENT-OFF* */
286  .function = virtio_input_fn,
287  .name = "virtio-input",
288  .sibling_of = "device-input",
289  .format_trace = format_virtio_input_trace,
290  .type = VLIB_NODE_TYPE_INPUT,
291  .state = VLIB_NODE_STATE_INTERRUPT,
292  .n_errors = TAP_INPUT_N_ERROR,
293  .error_strings = virtio_input_error_strings,
294 };
295 
297 /* *INDENT-ON* */
298 
299 /*
300  * fd.io coding-style-patch-verification: ON
301  *
302  * Local Variables:
303  * eval: (c-set-style "gnu")
304  * End:
305  */
u32 per_interface_next_index
Definition: virtio.h:101
struct vring_used * used
Definition: virtio.h:77
vlib_node_registration_t virtio_input_node
(constructor) VLIB_REGISTER_NODE (virtio_input_node)
Definition: node.c:285
virtio_if_t * interfaces
Definition: virtio.h:125
vnet_device_and_queue_t * devices_and_queues
Definition: devices.h:69
#define clib_min(x, y)
Definition: clib.h:291
#define CLIB_UNUSED(x)
Definition: clib.h:81
static u32 vlib_get_trace_count(vlib_main_t *vm, vlib_node_runtime_t *rt)
Definition: trace_funcs.h:156
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:204
u8 runtime_data[0]
Function dependent node-runtime data.
Definition: node.h:521
vnet_main_t * vnet_get_main(void)
Definition: misc.c:47
vnet_interface_main_t interface_main
Definition: vnet.h:56
#define CLIB_MEMORY_STORE_BARRIER()
Definition: clib.h:114
u32 dev_instance
Definition: virtio.h:98
static_always_inline void virtio_refill_vring(vlib_main_t *vm, virtio_vring_t *vring)
Definition: node.c:83
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)
Definition: node.c:131
u32 thread_index
Definition: main.h:179
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:419
static uword virtio_input_fn(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
Definition: node.c:262
virtio_vring_t * vrings
Definition: virtio.h:104
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:114
struct vring_avail * avail
Definition: virtio.h:78
i16 current_data
signed offset in data[], pre_data[] that we are currently processing.
Definition: buffer.h:109
#define static_always_inline
Definition: clib.h:95
u32 hw_if_index
Definition: virtio.h:99
vlib_combined_counter_main_t * combined_sw_if_counters
Definition: interface.h:855
u8 * format_white_space(u8 *s, va_list *va)
Definition: std-formats.c:113
#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:65
static char * virtio_input_error_strings[]
Definition: node.c:49
#define VLIB_NODE_FUNCTION_MULTIARCH(node, fn)
Definition: node.h:209
#define foreach_virtio_input_error
Definition: node.c:38
virtio_input_error_t
Definition: node.c:41
u16 current_length
Nbytes between current data and the end of this buffer.
Definition: buffer.h:113
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:205
#define PREDICT_FALSE(x)
Definition: clib.h:107
#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:364
u16 desc_next
Definition: virtio.h:80
u16 last_used_idx
Definition: virtio.h:88
#define VLIB_REGISTER_NODE(x,...)
Definition: node.h:155
static_always_inline void virtio_kick(virtio_vring_t *vring)
Definition: virtio.h:141
vlib_main_t * vm
Definition: buffer.c:294
#define VIRTIO_RING_FLAG_MASK_INT
Definition: virtio.h:84
#define clib_memcpy(a, b, c)
Definition: string.h:75
u32 flags
Definition: virtio.h:94
u16 last_kick_avail_idx
Definition: virtio.h:89
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:455
#define VLIB_BUFFER_DATA_SIZE
Definition: buffer.h:51
u32 next_buffer
Next buffer for this linked-list of buffers.
Definition: buffer.h:129
struct virtio_net_hdr_v1 hdr
Definition: node.c:61
static uword pointer_to_uword(const void *p)
Definition: types.h:131
virtio_main_t virtio_main
Definition: virtio.c:35
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:57
u32 total_length_not_including_first_buffer
Only valid for first buffer in chain.
Definition: buffer.h:155
#define foreach_device_and_queue(var, vec)
Definition: devices.h:156
Definition: defs.h:47
static u32 vlib_buffer_alloc_to_ring(vlib_main_t *vm, u32 *ring, u32 start, u32 ring_size, u32 n_buffers)
Allocate buffers into ring.
Definition: buffer_funcs.h:520
#define VLIB_BUFFER_TRACE_TRAJECTORY_INIT(b)
Definition: buffer.h:547
u64 uword
Definition: types.h:112
u32 * buffers
Definition: virtio.h:87
#define vnet_buffer(b)
Definition: buffer.h:344
u32 sw_if_index
Definition: virtio.h:100
static_always_inline void vnet_feature_start_device_input_x1(u32 sw_if_index, u32 *next0, vlib_buffer_t *b0)
Definition: feature.h:259
struct vring_desc * desc
Definition: virtio.h:76
static void vlib_set_trace_count(vlib_main_t *vm, vlib_node_runtime_t *rt, u32 count)
Definition: trace_funcs.h:172
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:116
static vlib_buffer_t * vlib_get_buffer(vlib_main_t *vm, u32 buffer_index)
Translate buffer index into buffer pointer.
Definition: buffer_funcs.h:58
u16 desc_in_use
Definition: virtio.h:79
Definition: defs.h:46