FD.io VPP  v18.07.1-19-g511ce25
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  used = vring->desc_in_use;
91 
92  if (sz - used < sz / 8)
93  return;
94 
95  n_slots = sz - used;
96  next = vring->desc_next;
97  avail = vring->avail->idx;
98  n_slots = vlib_buffer_alloc_to_ring (vm, vring->buffers, next, vring->size,
99  n_slots);
100 
101  while (n_slots)
102  {
103  struct vring_desc *d = &vring->desc[next];;
104  vlib_buffer_t *b = vlib_get_buffer (vm, vring->buffers[next]);
105  d->addr = pointer_to_uword (vlib_buffer_get_current (b)) - hdr_sz;
106  d->len = VLIB_BUFFER_DATA_SIZE + hdr_sz;
107  d->flags = VRING_DESC_F_WRITE;
108  vring->avail->ring[avail & mask] = next;
109  avail++;
110  next = (next + 1) & mask;
111  n_slots--;
112  used++;
113  }
115  vring->avail->idx = avail;
116  vring->desc_next = next;
117  vring->desc_in_use = used;
118 
119  if ((vring->used->flags & VIRTIO_RING_FLAG_MASK_INT) == 0)
120  {
121  u64 b = 1;
122  CLIB_UNUSED (int r) = write (vring->kick_fd, &b, sizeof (b));
123  }
124 }
125 
128  vlib_frame_t * frame, virtio_if_t * vif, u16 qid)
129 {
130  vnet_main_t *vnm = vnet_get_main ();
131  u32 thread_index = vm->thread_index;
132  uword n_trace = vlib_get_trace_count (vm, node);
133  virtio_vring_t *vring = vec_elt_at_index (vif->vrings, 0);
135  const int hdr_sz = sizeof (struct virtio_net_hdr_v1);
136  u32 *to_next = 0;
137  u32 n_rx_packets = 0;
138  u32 n_rx_bytes = 0;
139  u16 mask = vring->size - 1;
140  u16 last = vring->last_used_idx;
141  u16 n_left = vring->used->idx - last;
142 
143  if (n_left == 0)
144  goto refill;
145 
146  while (n_left)
147  {
148  u32 n_left_to_next;
149  u32 next0 = next_index;
150  vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
151 
152  while (n_left && n_left_to_next)
153  {
154  u16 num_buffers;
155  struct vring_used_elem *e = &vring->used->ring[last & mask];
156  struct virtio_net_hdr_v1 *hdr;
157  u16 slot = e->id;
158  u16 len = e->len - hdr_sz;
159  u32 bi0 = vring->buffers[slot];
160  vlib_buffer_t *b0 = vlib_get_buffer (vm, bi0);
161  hdr = vlib_buffer_get_current (b0) - hdr_sz;
162  num_buffers = hdr->num_buffers;
163 
164  b0->current_data = 0;
165  b0->current_length = len;
167  b0->flags = VLIB_BUFFER_TOTAL_LENGTH_VALID;
168  vnet_buffer (b0)->sw_if_index[VLIB_RX] = vif->sw_if_index;
169  vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
170 
171  /* if multisegment packet */
172  if (PREDICT_FALSE (num_buffers > 1))
173  {
174  vlib_buffer_t *pb, *cb;
175  pb = b0;
176  while (num_buffers > 1)
177  {
178  last++;
179  e = &vring->used->ring[last & mask];
180  u32 cbi = vring->buffers[e->id];
181  cb = vlib_get_buffer (vm, cbi);
182 
183  /* current buffer */
184  cb->current_data = -hdr_sz;
185  cb->current_length = e->len;
186 
187  /* previous buffer */
188  pb->next_buffer = cbi;
189  pb->flags |= VLIB_BUFFER_NEXT_PRESENT;
190 
191  /* first buffer */
193 
194  pb = cb;
195  vring->desc_in_use--;
196  num_buffers--;
197  n_left--;
198  }
199  }
200 
201  if (PREDICT_FALSE (vif->per_interface_next_index != ~0))
202  next0 = vif->per_interface_next_index;
203  else
204  /* redirect if feature path enabled */
206  /* trace */
208 
209  if (PREDICT_FALSE (n_trace > 0))
210  {
212  vlib_trace_buffer (vm, node, next0, b0,
213  /* follow_chain */ 0);
214  vlib_set_trace_count (vm, node, --n_trace);
215  tr = vlib_add_trace (vm, node, b0, sizeof (*tr));
216  tr->next_index = next0;
217  tr->hw_if_index = vif->hw_if_index;
218  tr->len = len;
219  clib_memcpy (&tr->hdr, hdr, hdr_sz);
220  }
221 
222  /* enqueue buffer */
223  to_next[0] = bi0;
224  vring->desc_in_use--;
225  to_next += 1;
226  n_left_to_next--;
227  n_left--;
228  last++;
229 
230  /* enqueue */
231  vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
232  n_left_to_next, bi0, next0);
233 
234  /* next packet */
235  n_rx_packets++;
236  n_rx_bytes += len;
237  }
238  vlib_put_next_frame (vm, node, next_index, n_left_to_next);
239  }
240  vring->last_used_idx = last;
241 
243  + VNET_INTERFACE_COUNTER_RX, thread_index,
244  vif->hw_if_index, n_rx_packets,
245  n_rx_bytes);
246 
247 refill:
248  virtio_refill_vring (vm, vring);
249 
250  return n_rx_packets;
251 }
252 
253 static uword
255  vlib_frame_t * frame)
256 {
257  u32 n_rx = 0;
258  virtio_main_t *nm = &virtio_main;
259  vnet_device_input_runtime_t *rt = (void *) node->runtime_data;
261 
263  {
264  virtio_if_t *mif;
265  mif = vec_elt_at_index (nm->interfaces, dq->dev_instance);
266  if (mif->flags & VIRTIO_IF_FLAG_ADMIN_UP)
267  {
268  n_rx += virtio_device_input_inline (vm, node, frame, mif,
269  dq->queue_id);
270  }
271  }
272 
273  return n_rx;
274 }
275 
276 /* *INDENT-OFF* */
278  .function = virtio_input_fn,
279  .name = "virtio-input",
280  .sibling_of = "device-input",
281  .format_trace = format_virtio_input_trace,
282  .type = VLIB_NODE_TYPE_INPUT,
283  .state = VLIB_NODE_STATE_INTERRUPT,
284  .n_errors = TAP_INPUT_N_ERROR,
285  .error_strings = virtio_input_error_strings,
286 };
287 
289 /* *INDENT-ON* */
290 
291 /*
292  * fd.io coding-style-patch-verification: ON
293  *
294  * Local Variables:
295  * eval: (c-set-style "gnu")
296  * End:
297  */
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:277
virtio_if_t * interfaces
Definition: virtio.h:124
vnet_device_and_queue_t * devices_and_queues
Definition: devices.h:69
#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:213
u8 runtime_data[0]
Function dependent node-runtime data.
Definition: node.h:500
vnet_main_t * vnet_get_main(void)
Definition: misc.c:47
vnet_interface_main_t interface_main
Definition: vnet.h:56
unsigned long u64
Definition: types.h:89
#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:127
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:254
virtio_vring_t * vrings
Definition: virtio.h:103
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:104
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:104
#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:811
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 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:108
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:202
#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
#define VLIB_REGISTER_NODE(x,...)
Definition: node.h:153
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: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
u32 next_buffer
Next buffer for this linked-list of buffers.
Definition: buffer.h:126
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:55
u32 total_length_not_including_first_buffer
Only valid for first buffer in chain.
Definition: buffer.h:152
#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:507
#define VLIB_BUFFER_TRACE_TRAJECTORY_INIT(b)
Definition: buffer.h:546
u64 uword
Definition: types.h:112
u32 * buffers
Definition: virtio.h:87
#define vnet_buffer(b)
Definition: buffer.h:360
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:250
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:111
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:1216
u16 desc_in_use
Definition: virtio.h:79
Definition: defs.h:46