FD.io VPP  v18.01.2-1-g9b554f3
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, n_alloc;
87  u16 sz = vring->size;
88  u16 mask = sz - 1;
89  int i;
90 
91  used = vring->desc_in_use;
92 
93  if (sz - used < sz / 8)
94  return;
95 
96  n_slots = sz - used;
97  next = vring->desc_next;
98  avail = vring->avail->idx;
99  n_alloc = vlib_buffer_alloc (vm, &vring->buffers[next], n_slots);
100 
101  if (PREDICT_FALSE (n_alloc < n_slots))
102  n_slots = n_alloc;
103 
104  i = next + n_slots - sz;
105  if (PREDICT_FALSE (i > 0))
106  clib_memcpy (vring->buffers, &vring->buffers[sz], i * sizeof (u32));
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  d->addr = pointer_to_uword (vlib_buffer_get_current (b)) - hdr_sz;
113  d->len = VLIB_BUFFER_DATA_SIZE + hdr_sz;
114  d->flags = VRING_DESC_F_WRITE;
115  vring->avail->ring[avail & mask] = next;
116  avail++;
117  next = (next + 1) & mask;
118  n_slots--;
119  used++;
120  }
122  vring->avail->idx = avail;
123  vring->desc_next = next;
124  vring->desc_in_use = used;
125 
126  if ((vring->used->flags & VIRTIO_RING_FLAG_MASK_INT) == 0)
127  {
128  u64 b = 1;
129  CLIB_UNUSED (int r) = write (vring->kick_fd, &b, sizeof (b));
130  }
131 }
132 
135  vlib_frame_t * frame, virtio_if_t * vif, u16 qid)
136 {
137  vnet_main_t *vnm = vnet_get_main ();
138  u32 thread_index = vlib_get_thread_index ();
139  uword n_trace = vlib_get_trace_count (vm, node);
140  virtio_vring_t *vring = vec_elt_at_index (vif->vrings, 0);
142  const int hdr_sz = sizeof (struct virtio_net_hdr_v1);
143  u32 *to_next = 0;
144  u32 n_rx_packets = 0;
145  u32 n_rx_bytes = 0;
146  u16 mask = vring->size - 1;
147  u16 last = vring->last_used_idx;
148  u16 n_left = vring->used->idx - last;
149 
150  if (n_left == 0)
151  goto refill;
152 
153  while (n_left)
154  {
155  u32 n_left_to_next;
156  u32 next0 = next_index;
157  vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
158 
159  while (n_left && n_left_to_next)
160  {
161  u16 num_buffers;
162  struct vring_used_elem *e = &vring->used->ring[last & mask];
163  struct virtio_net_hdr_v1 *hdr;
164  u16 slot = e->id;
165  u16 len = e->len - hdr_sz;
166  u32 bi0 = vring->buffers[slot];
167  vlib_buffer_t *b0 = vlib_get_buffer (vm, bi0);
168  hdr = vlib_buffer_get_current (b0) - hdr_sz;
169  num_buffers = hdr->num_buffers;
170 
171  b0->current_data = 0;
172  b0->current_length = len;
175  vnet_buffer (b0)->sw_if_index[VLIB_RX] = vif->sw_if_index;
176  vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
177 
178  /* if multisegment packet */
179  if (PREDICT_FALSE (num_buffers > 1))
180  {
181  vlib_buffer_t *pb, *cb;
182  pb = b0;
183  while (num_buffers > 1)
184  {
185  last++;
186  e = &vring->used->ring[last & mask];
187  u32 cbi = vring->buffers[e->id];
188  cb = vlib_get_buffer (vm, cbi);
189 
190  /* current buffer */
191  cb->current_data = -hdr_sz;
192  cb->current_length = e->len;
193 
194  /* previous buffer */
195  pb->next_buffer = cbi;
197 
198  /* first buffer */
200 
201  pb = cb;
202  vring->desc_in_use--;
203  num_buffers--;
204  n_left--;
205  }
206  }
207 
208  if (PREDICT_FALSE (vif->per_interface_next_index != ~0))
209  next0 = vif->per_interface_next_index;
210  else
211  /* redirect if feature path enabled */
213  /* trace */
215 
216  if (PREDICT_FALSE (n_trace > 0))
217  {
219  vlib_trace_buffer (vm, node, next0, b0,
220  /* follow_chain */ 0);
221  vlib_set_trace_count (vm, node, --n_trace);
222  tr = vlib_add_trace (vm, node, b0, sizeof (*tr));
223  tr->next_index = next0;
224  tr->hw_if_index = vif->hw_if_index;
225  tr->len = len;
226  clib_memcpy (&tr->hdr, hdr, hdr_sz);
227  }
228 
229  /* enqueue buffer */
230  to_next[0] = bi0;
231  vring->desc_in_use--;
232  to_next += 1;
233  n_left_to_next--;
234  n_left--;
235  last++;
236 
237  /* enqueue */
238  vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
239  n_left_to_next, bi0, next0);
240 
241  /* next packet */
242  n_rx_packets++;
243  n_rx_bytes += len;
244  }
245  vlib_put_next_frame (vm, node, next_index, n_left_to_next);
246  }
247  vring->last_used_idx = last;
248 
250  + VNET_INTERFACE_COUNTER_RX, thread_index,
251  vif->hw_if_index, n_rx_packets,
252  n_rx_bytes);
253 
254 refill:
255  virtio_refill_vring (vm, vring);
256 
257  return n_rx_packets;
258 }
259 
260 static uword
262  vlib_frame_t * frame)
263 {
264  u32 n_rx = 0;
265  virtio_main_t *nm = &virtio_main;
266  vnet_device_input_runtime_t *rt = (void *) node->runtime_data;
268 
270  {
271  virtio_if_t *mif;
272  mif = vec_elt_at_index (nm->interfaces, dq->dev_instance);
273  if (mif->flags & VIRTIO_IF_FLAG_ADMIN_UP)
274  {
275  n_rx += virtio_device_input_inline (vm, node, frame, mif,
276  dq->queue_id);
277  }
278  }
279 
280  return n_rx;
281 }
282 
283 /* *INDENT-OFF* */
285  .function = virtio_input_fn,
286  .name = "virtio-input",
287  .sibling_of = "device-input",
288  .format_trace = format_virtio_input_trace,
289  .type = VLIB_NODE_TYPE_INPUT,
290  .state = VLIB_NODE_STATE_INTERRUPT,
291  .n_errors = TAP_INPUT_N_ERROR,
292  .error_strings = virtio_input_error_strings,
293 };
294 
296 /* *INDENT-ON* */
297 
298 /*
299  * fd.io coding-style-patch-verification: ON
300  *
301  * Local Variables:
302  * eval: (c-set-style "gnu")
303  * End:
304  */
u32 per_interface_next_index
Definition: virtio.h:100
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:284
virtio_if_t * interfaces
Definition: virtio.h:124
vnet_device_and_queue_t * devices_and_queues
Definition: devices.h:69
sll srl srl sll sra u16x4 i
Definition: vector_sse2.h:337
#define CLIB_UNUSED(x)
Definition: clib.h:79
static u32 vlib_get_trace_count(vlib_main_t *vm, vlib_node_runtime_t *rt)
Definition: trace_funcs.h:143
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:211
u8 runtime_data[0]
Function dependent node-runtime data.
Definition: node.h:464
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:112
u32 dev_instance
Definition: virtio.h:97
static_always_inline void virtio_refill_vring(vlib_main_t *vm, virtio_vring_t *vring)
Definition: node.c:83
int kick_fd
Definition: virtio.h:81
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:134
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:261
virtio_vring_t * vrings
Definition: virtio.h:103
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:104
#define VLIB_BUFFER_NEXT_PRESENT
Definition: buffer.h:95
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:68
#define static_always_inline
Definition: clib.h:93
u32 hw_if_index
Definition: virtio.h:98
vlib_combined_counter_main_t * combined_sw_if_counters
Definition: interface.h:672
u8 * format_white_space(u8 *s, va_list *va)
Definition: std-formats.c:113
#define VLIB_BUFFER_TOTAL_LENGTH_VALID
Definition: buffer.h:97
#define vec_elt_at_index(v, i)
Get vector value at index i checking that i is in bounds.
unsigned long u64
Definition: types.h:89
static u8 * format_virtio_input_trace(u8 *s, va_list *args)
Definition: node.c:65
static uword pointer_to_uword(const void *p)
Definition: types.h:131
static char * virtio_input_error_strings[]
Definition: node.c:49
#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:72
static void * vlib_buffer_get_current(vlib_buffer_t *b)
Get pointer to current data to process.
Definition: buffer.h:195
#define PREDICT_FALSE(x)
Definition: clib.h:105
#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
static_always_inline uword vlib_get_thread_index(void)
Definition: threads.h:221
vlib_main_t * vm
Definition: buffer.c:283
#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:93
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:454
#define VLIB_BUFFER_DATA_SIZE
Definition: buffer.h:51
unsigned int u32
Definition: types.h:88
u32 next_buffer
Next buffer for this linked-list of buffers.
Definition: buffer.h:109
struct virtio_net_hdr_v1 hdr
Definition: node.c:61
virtio_main_t virtio_main
Definition: virtio.c:35
u64 uword
Definition: types.h:112
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
u32 total_length_not_including_first_buffer
Only valid for first buffer in chain.
Definition: buffer.h:142
#define foreach_device_and_queue(var, vec)
Definition: devices.h:156
Definition: defs.h:47
unsigned short u16
Definition: types.h:57
unsigned char u8
Definition: types.h:56
#define VLIB_BUFFER_TRACE_TRAJECTORY_INIT(b)
Definition: buffer.h:534
u32 * buffers
Definition: virtio.h:87
#define vnet_buffer(b)
Definition: buffer.h:326
u32 sw_if_index
Definition: virtio.h:99
static_always_inline void vnet_feature_start_device_input_x1(u32 sw_if_index, u32 *next0, vlib_buffer_t *b0)
Definition: feature.h:227
#define VLIB_REGISTER_NODE(x,...)
Definition: node.h:143
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:159
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:75
static u32 vlib_buffer_alloc(vlib_main_t *vm, u32 *buffers, u32 n_buffers)
Allocate buffers into supplied array.
Definition: buffer_funcs.h:341
static vlib_buffer_t * vlib_get_buffer(vlib_main_t *vm, u32 buffer_index)
Translate buffer index into buffer pointer.
Definition: buffer_funcs.h:57
VLIB_NODE_FUNCTION_MULTIARCH(ethernet_input_not_l2_node, ethernet_input_not_l2)
Definition: node.c:1229
u16 desc_in_use
Definition: virtio.h:79
Definition: defs.h:46