2 * Copyright (c) 2015 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
16 * buffer_funcs.h: VLIB buffer related functions/inlines
18 * Copyright (c) 2008 Eliot Dresselhaus
20 * Permission is hereby granted, free of charge, to any person obtaining
21 * a copy of this software and associated documentation files (the
22 * "Software"), to deal in the Software without restriction, including
23 * without limitation the rights to use, copy, modify, merge, publish,
24 * distribute, sublicense, and/or sell copies of the Software, and to
25 * permit persons to whom the Software is furnished to do so, subject to
26 * the following conditions:
28 * The above copyright notice and this permission notice shall be
29 * included in all copies or substantial portions of the Software.
31 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
32 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
33 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
34 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
35 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
36 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
37 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
40 #ifndef included_vlib_buffer_funcs_h
41 #define included_vlib_buffer_funcs_h
43 #include <vppinfra/hash.h>
46 vlib buffer access methods.
50 /** \brief Translate buffer index into buffer pointer
52 @param vm - (vlib_main_t *) vlib main data structure pointer
53 @param buffer_index - (u32) buffer index
54 @return - (vlib_buffer_t *) buffer pointer
56 always_inline vlib_buffer_t *
57 vlib_get_buffer (vlib_main_t * vm, u32 buffer_index)
59 vlib_buffer_main_t *bm = vm->buffer_main;
60 uword offset = ((uword) buffer_index) << CLIB_LOG2_CACHE_LINE_BYTES;
61 ASSERT (offset < bm->buffer_mem_size);
63 return uword_to_pointer (bm->buffer_mem_start + offset, void *);
66 /** \brief Translate buffer pointer into buffer index
68 @param vm - (vlib_main_t *) vlib main data structure pointer
69 @param p - (void *) buffer pointer
70 @return - (u32) buffer index
74 vlib_get_buffer_index (vlib_main_t * vm, void *p)
76 vlib_buffer_main_t *bm = vm->buffer_main;
77 uword offset = pointer_to_uword (p) - bm->buffer_mem_start;
78 ASSERT (pointer_to_uword (p) >= bm->buffer_mem_start);
79 ASSERT (offset < bm->buffer_mem_size);
80 ASSERT ((offset % (1 << CLIB_LOG2_CACHE_LINE_BYTES)) == 0);
81 return offset >> CLIB_LOG2_CACHE_LINE_BYTES;
84 /** \brief Get next buffer in buffer linklist, or zero for end of list.
86 @param vm - (vlib_main_t *) vlib main data structure pointer
87 @param b - (void *) buffer pointer
88 @return - (vlib_buffer_t *) next buffer, or NULL
90 always_inline vlib_buffer_t *
91 vlib_get_next_buffer (vlib_main_t * vm, vlib_buffer_t * b)
93 return (b->flags & VLIB_BUFFER_NEXT_PRESENT
94 ? vlib_get_buffer (vm, b->next_buffer) : 0);
97 uword vlib_buffer_length_in_chain_slow_path (vlib_main_t * vm,
98 vlib_buffer_t * b_first);
100 /** \brief Get length in bytes of the buffer chain
102 @param vm - (vlib_main_t *) vlib main data structure pointer
103 @param b - (void *) buffer pointer
104 @return - (uword) length of buffer chain
107 vlib_buffer_length_in_chain (vlib_main_t * vm, vlib_buffer_t * b)
109 uword len = b->current_length;
111 if (PREDICT_TRUE ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0))
114 if (PREDICT_TRUE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID))
115 return len + b->total_length_not_including_first_buffer;
117 return vlib_buffer_length_in_chain_slow_path (vm, b);
120 /** \brief Get length in bytes of the buffer index buffer chain
122 @param vm - (vlib_main_t *) vlib main data structure pointer
123 @param bi - (u32) buffer index
124 @return - (uword) length of buffer chain
127 vlib_buffer_index_length_in_chain (vlib_main_t * vm, u32 bi)
129 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
130 return vlib_buffer_length_in_chain (vm, b);
133 /** \brief Copy buffer contents to memory
135 @param vm - (vlib_main_t *) vlib main data structure pointer
136 @param buffer_index - (u32) buffer index
137 @param contents - (u8 *) memory, <strong>must be large enough</strong>
138 @return - (uword) length of buffer chain
141 vlib_buffer_contents (vlib_main_t * vm, u32 buffer_index, u8 * contents)
143 uword content_len = 0;
149 b = vlib_get_buffer (vm, buffer_index);
150 l = b->current_length;
151 clib_memcpy (contents + content_len, b->data + b->current_data, l);
153 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
155 buffer_index = b->next_buffer;
161 /* Return physical address of buffer->data start. */
163 vlib_get_buffer_data_physical_address (vlib_main_t * vm, u32 buffer_index)
165 vlib_buffer_main_t *bm = vm->buffer_main;
166 vlib_buffer_t *b = vlib_get_buffer (vm, buffer_index);
167 vlib_buffer_pool_t *pool = vec_elt_at_index (bm->buffer_pools,
168 b->buffer_pool_index);
170 return vlib_physmem_virtual_to_physical (vm, pool->physmem_region, b->data);
173 /** \brief Prefetch buffer metadata by buffer index
174 The first 64 bytes of buffer contains most header information
176 @param vm - (vlib_main_t *) vlib main data structure pointer
177 @param bi - (u32) buffer index
178 @param type - LOAD, STORE. In most cases, STORE is the right answer
180 /* Prefetch buffer header given index. */
181 #define vlib_prefetch_buffer_with_index(vm,bi,type) \
183 vlib_buffer_t * _b = vlib_get_buffer (vm, bi); \
184 vlib_prefetch_buffer_header (_b, type); \
188 /* Iterate over known allocated vlib bufs. You probably do not want
190 @param vm the vlib_main_t
191 @param bi found allocated buffer index
192 @param body operation to perform on buffer index
193 function executes body for each allocated buffer index
195 #define vlib_buffer_foreach_allocated(vm,bi,body) \
197 vlib_main_t * _vmain = (vm); \
198 vlib_buffer_main_t * _bmain = &_vmain->buffer_main; \
199 hash_pair_t * _vbpair; \
200 hash_foreach_pair(_vbpair, _bmain->buffer_known_hash, ({ \
201 if (VLIB_BUFFER_KNOWN_ALLOCATED == _vbpair->value[0]) { \
202 (bi) = _vbpair->key; \
211 /* Index is unknown. */
214 /* Index is known and free/allocated. */
215 VLIB_BUFFER_KNOWN_FREE,
216 VLIB_BUFFER_KNOWN_ALLOCATED,
217 } vlib_buffer_known_state_t;
219 void vlib_buffer_validate_alloc_free (vlib_main_t * vm, u32 * buffers,
221 vlib_buffer_known_state_t
224 always_inline vlib_buffer_known_state_t
225 vlib_buffer_is_known (u32 buffer_index)
227 vlib_buffer_main_t *bm = vlib_global_main.buffer_main;
229 clib_spinlock_lock (&bm->buffer_known_hash_lockp);
230 uword *p = hash_get (bm->buffer_known_hash, buffer_index);
231 clib_spinlock_unlock (&bm->buffer_known_hash_lockp);
232 return p ? p[0] : VLIB_BUFFER_UNKNOWN;
236 vlib_buffer_set_known_state (u32 buffer_index,
237 vlib_buffer_known_state_t state)
239 vlib_buffer_main_t *bm = vlib_global_main.buffer_main;
241 clib_spinlock_lock (&bm->buffer_known_hash_lockp);
242 hash_set (bm->buffer_known_hash, buffer_index, state);
243 clib_spinlock_unlock (&bm->buffer_known_hash_lockp);
246 /* Validates sanity of a single buffer.
247 Returns format'ed vector with error message if any. */
248 u8 *vlib_validate_buffer (vlib_main_t * vm, u32 buffer_index,
252 vlib_buffer_round_size (u32 size)
254 return round_pow2 (size, sizeof (vlib_buffer_t));
257 always_inline vlib_buffer_free_list_index_t
258 vlib_buffer_get_free_list_index (vlib_buffer_t * b)
260 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NON_DEFAULT_FREELIST))
261 return b->free_list_index;
267 vlib_buffer_set_free_list_index (vlib_buffer_t * b,
268 vlib_buffer_free_list_index_t index)
270 if (PREDICT_FALSE (index))
272 b->flags |= VLIB_BUFFER_NON_DEFAULT_FREELIST;
273 b->free_list_index = index;
276 b->flags &= ~VLIB_BUFFER_NON_DEFAULT_FREELIST;
279 /** \brief Allocate buffers from specific freelist into supplied array
281 @param vm - (vlib_main_t *) vlib main data structure pointer
282 @param buffers - (u32 * ) buffer index array
283 @param n_buffers - (u32) number of buffers requested
284 @return - (u32) number of buffers actually allocated, may be
285 less than the number requested or zero
288 vlib_buffer_alloc_from_free_list (vlib_main_t * vm,
291 vlib_buffer_free_list_index_t index)
293 vlib_buffer_main_t *bm = vm->buffer_main;
294 vlib_buffer_free_list_t *fl;
298 ASSERT (bm->cb.vlib_buffer_fill_free_list_cb);
300 fl = pool_elt_at_index (bm->buffer_free_list_pool, index);
302 len = vec_len (fl->buffers);
304 if (PREDICT_FALSE (len < n_buffers))
306 bm->cb.vlib_buffer_fill_free_list_cb (vm, fl, n_buffers);
307 len = vec_len (fl->buffers);
309 /* even if fill free list didn't manage to refill free list
310 we should give what we have */
311 n_buffers = clib_min (len, n_buffers);
313 /* following code is intentionaly duplicated to allow compiler
314 to optimize fast path when n_buffers is constant value */
315 src = fl->buffers + len - n_buffers;
316 clib_memcpy (buffers, src, n_buffers * sizeof (u32));
317 _vec_len (fl->buffers) -= n_buffers;
319 /* Verify that buffers are known free. */
320 vlib_buffer_validate_alloc_free (vm, buffers, n_buffers,
321 VLIB_BUFFER_KNOWN_FREE);
326 src = fl->buffers + len - n_buffers;
327 clib_memcpy (buffers, src, n_buffers * sizeof (u32));
328 _vec_len (fl->buffers) -= n_buffers;
330 /* Verify that buffers are known free. */
331 vlib_buffer_validate_alloc_free (vm, buffers, n_buffers,
332 VLIB_BUFFER_KNOWN_FREE);
337 /** \brief Allocate buffers into supplied array
339 @param vm - (vlib_main_t *) vlib main data structure pointer
340 @param buffers - (u32 * ) buffer index array
341 @param n_buffers - (u32) number of buffers requested
342 @return - (u32) number of buffers actually allocated, may be
343 less than the number requested or zero
346 vlib_buffer_alloc (vlib_main_t * vm, u32 * buffers, u32 n_buffers)
348 return vlib_buffer_alloc_from_free_list (vm, buffers, n_buffers,
349 VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);
352 /** \brief Allocate buffers into ring
354 @param vm - (vlib_main_t *) vlib main data structure pointer
355 @param buffers - (u32 * ) buffer index ring
356 @param start - (u32) first slot in the ring
357 @param ring_size - (u32) ring size
358 @param n_buffers - (u32) number of buffers requested
359 @return - (u32) number of buffers actually allocated, may be
360 less than the number requested or zero
363 vlib_buffer_alloc_to_ring (vlib_main_t * vm, u32 * ring, u32 start,
364 u32 ring_size, u32 n_buffers)
368 ASSERT (n_buffers <= ring_size);
370 if (PREDICT_TRUE (start + n_buffers <= ring_size))
371 return vlib_buffer_alloc (vm, ring + start, n_buffers);
373 n_alloc = vlib_buffer_alloc (vm, ring + start, ring_size - start);
375 if (PREDICT_TRUE (n_alloc == ring_size - start))
376 n_alloc += vlib_buffer_alloc (vm, ring, n_buffers - n_alloc);
381 /** \brief Free buffers
382 Frees the entire buffer chain for each buffer
384 @param vm - (vlib_main_t *) vlib main data structure pointer
385 @param buffers - (u32 * ) buffer index array
386 @param n_buffers - (u32) number of buffers to free
390 vlib_buffer_free (vlib_main_t * vm,
391 /* pointer to first buffer */
393 /* number of buffers to free */
396 vlib_buffer_main_t *bm = vm->buffer_main;
398 ASSERT (bm->cb.vlib_buffer_free_cb);
400 return bm->cb.vlib_buffer_free_cb (vm, buffers, n_buffers);
403 /** \brief Free buffers, does not free the buffer chain for each buffer
405 @param vm - (vlib_main_t *) vlib main data structure pointer
406 @param buffers - (u32 * ) buffer index array
407 @param n_buffers - (u32) number of buffers to free
411 vlib_buffer_free_no_next (vlib_main_t * vm,
412 /* pointer to first buffer */
414 /* number of buffers to free */
417 vlib_buffer_main_t *bm = vm->buffer_main;
419 ASSERT (bm->cb.vlib_buffer_free_no_next_cb);
421 return bm->cb.vlib_buffer_free_no_next_cb (vm, buffers, n_buffers);
424 /** \brief Free one buffer
425 Shorthand to free a single buffer chain.
427 @param vm - (vlib_main_t *) vlib main data structure pointer
428 @param buffer_index - (u32) buffer index to free
431 vlib_buffer_free_one (vlib_main_t * vm, u32 buffer_index)
433 vlib_buffer_free (vm, &buffer_index, /* n_buffers */ 1);
436 /** \brief Free buffers from ring
438 @param vm - (vlib_main_t *) vlib main data structure pointer
439 @param buffers - (u32 * ) buffer index ring
440 @param start - (u32) first slot in the ring
441 @param ring_size - (u32) ring size
442 @param n_buffers - (u32) number of buffers
445 vlib_buffer_free_from_ring (vlib_main_t * vm, u32 * ring, u32 start,
446 u32 ring_size, u32 n_buffers)
448 ASSERT (n_buffers <= ring_size);
450 if (PREDICT_TRUE (start + n_buffers <= ring_size))
452 vlib_buffer_free (vm, ring + start, n_buffers);
456 vlib_buffer_free (vm, ring + start, ring_size - start);
457 vlib_buffer_free (vm, ring, n_buffers - (ring_size - start));
462 /* Add/delete buffer free lists. */
463 vlib_buffer_free_list_index_t vlib_buffer_create_free_list (vlib_main_t * vm,
467 vlib_buffer_delete_free_list (vlib_main_t * vm,
468 vlib_buffer_free_list_index_t free_list_index)
470 vlib_buffer_main_t *bm = vm->buffer_main;
472 ASSERT (bm->cb.vlib_buffer_delete_free_list_cb);
474 bm->cb.vlib_buffer_delete_free_list_cb (vm, free_list_index);
477 /* Find already existing public free list with given size or create one. */
478 vlib_buffer_free_list_index_t vlib_buffer_get_or_create_free_list (vlib_main_t
485 /* Merge two free lists */
486 void vlib_buffer_merge_free_lists (vlib_buffer_free_list_t * dst,
487 vlib_buffer_free_list_t * src);
489 /* Make sure we have at least given number of unaligned buffers. */
490 void vlib_buffer_free_list_fill_unaligned (vlib_main_t * vm,
491 vlib_buffer_free_list_t *
493 uword n_unaligned_buffers);
495 always_inline vlib_buffer_free_list_index_t
496 vlib_buffer_get_free_list_with_size (vlib_main_t * vm, u32 size)
498 vlib_buffer_main_t *bm = vm->buffer_main;
500 size = vlib_buffer_round_size (size);
501 uword *p = hash_get (bm->free_list_by_size, size);
502 return p ? p[0] : ~0;
505 always_inline vlib_buffer_free_list_t *
506 vlib_buffer_get_buffer_free_list (vlib_main_t * vm, vlib_buffer_t * b,
507 vlib_buffer_free_list_index_t * index)
509 vlib_buffer_main_t *bm = vm->buffer_main;
510 vlib_buffer_free_list_index_t i;
512 *index = i = vlib_buffer_get_free_list_index (b);
513 return pool_elt_at_index (bm->buffer_free_list_pool, i);
516 always_inline vlib_buffer_free_list_t *
517 vlib_buffer_get_free_list (vlib_main_t * vm,
518 vlib_buffer_free_list_index_t free_list_index)
520 vlib_buffer_main_t *bm = vm->buffer_main;
521 vlib_buffer_free_list_t *f;
523 f = pool_elt_at_index (bm->buffer_free_list_pool, free_list_index);
525 /* Sanity: indices must match. */
526 ASSERT (f->index == free_list_index);
532 vlib_buffer_free_list_buffer_size (vlib_main_t * vm,
533 vlib_buffer_free_list_index_t index)
535 vlib_buffer_free_list_t *f = vlib_buffer_get_free_list (vm, index);
536 return f->n_data_bytes;
539 void vlib_aligned_memcpy (void *_dst, void *_src, int n_bytes);
541 /* Reasonably fast buffer copy routine. */
543 vlib_copy_buffers (u32 * dst, u32 * src, u32 n)
564 /* Append given data to end of buffer, possibly allocating new buffers. */
565 u32 vlib_buffer_add_data (vlib_main_t * vm,
566 vlib_buffer_free_list_index_t free_list_index,
567 u32 buffer_index, void *data, u32 n_data_bytes);
569 /* duplicate all buffers in chain */
570 always_inline vlib_buffer_t *
571 vlib_buffer_copy (vlib_main_t * vm, vlib_buffer_t * b)
573 vlib_buffer_t *s, *d, *fd;
574 uword n_alloc, n_buffers = 1;
575 u32 flag_mask = VLIB_BUFFER_NEXT_PRESENT | VLIB_BUFFER_TOTAL_LENGTH_VALID;
579 while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
582 s = vlib_get_buffer (vm, s->next_buffer);
584 u32 new_buffers[n_buffers];
586 n_alloc = vlib_buffer_alloc (vm, new_buffers, n_buffers);
588 /* No guarantee that we'll get all the buffers we asked for */
589 if (PREDICT_FALSE (n_alloc < n_buffers))
592 vlib_buffer_free (vm, new_buffers, n_alloc);
598 fd = d = vlib_get_buffer (vm, new_buffers[0]);
599 d->current_data = s->current_data;
600 d->current_length = s->current_length;
601 d->flags = s->flags & flag_mask;
602 d->total_length_not_including_first_buffer =
603 s->total_length_not_including_first_buffer;
604 clib_memcpy (d->opaque, s->opaque, sizeof (s->opaque));
605 clib_memcpy (vlib_buffer_get_current (d),
606 vlib_buffer_get_current (s), s->current_length);
609 for (i = 1; i < n_buffers; i++)
612 d->next_buffer = new_buffers[i];
614 s = vlib_get_buffer (vm, s->next_buffer);
615 d = vlib_get_buffer (vm, new_buffers[i]);
616 d->current_data = s->current_data;
617 d->current_length = s->current_length;
618 clib_memcpy (vlib_buffer_get_current (d),
619 vlib_buffer_get_current (s), s->current_length);
620 d->flags = s->flags & flag_mask;
626 /** \brief Create a maximum of 256 clones of buffer and store them
627 in the supplied array
629 @param vm - (vlib_main_t *) vlib main data structure pointer
630 @param src_buffer - (u32) source buffer index
631 @param buffers - (u32 * ) buffer index array
632 @param n_buffers - (u16) number of buffer clones requested (<=256)
633 @param head_end_offset - (u16) offset relative to current position
634 where packet head ends
635 @return - (u16) number of buffers actually cloned, may be
636 less than the number requested or zero
639 vlib_buffer_clone_256 (vlib_main_t * vm, u32 src_buffer, u32 * buffers,
640 u16 n_buffers, u16 head_end_offset)
643 vlib_buffer_t *s = vlib_get_buffer (vm, src_buffer);
645 ASSERT (s->n_add_refs == 0);
647 ASSERT (n_buffers <= 256);
649 if (s->current_length <= head_end_offset + CLIB_CACHE_LINE_BYTES * 2)
651 buffers[0] = src_buffer;
652 for (i = 1; i < n_buffers; i++)
655 d = vlib_buffer_copy (vm, s);
658 buffers[i] = vlib_get_buffer_index (vm, d);
664 if (PREDICT_FALSE (n_buffers == 1))
666 buffers[0] = src_buffer;
670 n_buffers = vlib_buffer_alloc_from_free_list (vm, buffers, n_buffers,
671 vlib_buffer_get_free_list_index
674 for (i = 0; i < n_buffers; i++)
676 vlib_buffer_t *d = vlib_get_buffer (vm, buffers[i]);
677 d->current_data = s->current_data;
678 d->current_length = head_end_offset;
679 vlib_buffer_set_free_list_index (d,
680 vlib_buffer_get_free_list_index (s));
681 d->total_length_not_including_first_buffer =
682 s->total_length_not_including_first_buffer + s->current_length -
684 d->flags = s->flags | VLIB_BUFFER_NEXT_PRESENT;
685 d->flags &= ~VLIB_BUFFER_EXT_HDR_VALID;
686 clib_memcpy (d->opaque, s->opaque, sizeof (s->opaque));
687 clib_memcpy (vlib_buffer_get_current (d), vlib_buffer_get_current (s),
689 d->next_buffer = src_buffer;
691 vlib_buffer_advance (s, head_end_offset);
692 s->n_add_refs = n_buffers - 1;
693 while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
695 s = vlib_get_buffer (vm, s->next_buffer);
696 s->n_add_refs = n_buffers - 1;
702 /** \brief Create multiple clones of buffer and store them
703 in the supplied array
705 @param vm - (vlib_main_t *) vlib main data structure pointer
706 @param src_buffer - (u32) source buffer index
707 @param buffers - (u32 * ) buffer index array
708 @param n_buffers - (u16) number of buffer clones requested (<=256)
709 @param head_end_offset - (u16) offset relative to current position
710 where packet head ends
711 @return - (u16) number of buffers actually cloned, may be
712 less than the number requested or zero
715 vlib_buffer_clone (vlib_main_t * vm, u32 src_buffer, u32 * buffers,
716 u16 n_buffers, u16 head_end_offset)
718 vlib_buffer_t *s = vlib_get_buffer (vm, src_buffer);
721 while (n_buffers > 256)
724 copy = vlib_buffer_copy (vm, s);
725 n_cloned += vlib_buffer_clone_256 (vm,
726 vlib_get_buffer_index (vm, copy),
727 (buffers + n_cloned),
728 256, head_end_offset);
731 n_cloned += vlib_buffer_clone_256 (vm, src_buffer,
733 n_buffers, head_end_offset);
738 /** \brief Attach cloned tail to the buffer
740 @param vm - (vlib_main_t *) vlib main data structure pointer
741 @param head - (vlib_buffer_t *) head buffer
742 @param tail - (Vlib buffer_t *) tail buffer to clone and attach to head
746 vlib_buffer_attach_clone (vlib_main_t * vm, vlib_buffer_t * head,
747 vlib_buffer_t * tail)
749 ASSERT ((head->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
750 ASSERT (vlib_buffer_get_free_list_index (head) ==
751 vlib_buffer_get_free_list_index (tail));
753 head->flags |= VLIB_BUFFER_NEXT_PRESENT;
754 head->flags &= ~VLIB_BUFFER_TOTAL_LENGTH_VALID;
755 head->flags &= ~VLIB_BUFFER_EXT_HDR_VALID;
756 head->flags |= (tail->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID);
757 head->next_buffer = vlib_get_buffer_index (vm, tail);
758 head->total_length_not_including_first_buffer = tail->current_length +
759 tail->total_length_not_including_first_buffer;
762 __sync_add_and_fetch (&tail->n_add_refs, 1);
764 if (tail->flags & VLIB_BUFFER_NEXT_PRESENT)
766 tail = vlib_get_buffer (vm, tail->next_buffer);
771 /* Initializes the buffer as an empty packet with no chained buffers. */
773 vlib_buffer_chain_init (vlib_buffer_t * first)
775 first->total_length_not_including_first_buffer = 0;
776 first->current_length = 0;
777 first->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
778 first->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
781 /* The provided next_bi buffer index is appended to the end of the packet. */
782 always_inline vlib_buffer_t *
783 vlib_buffer_chain_buffer (vlib_main_t * vm,
784 vlib_buffer_t * first,
785 vlib_buffer_t * last, u32 next_bi)
787 vlib_buffer_t *next_buffer = vlib_get_buffer (vm, next_bi);
788 last->next_buffer = next_bi;
789 last->flags |= VLIB_BUFFER_NEXT_PRESENT;
790 next_buffer->current_length = 0;
791 next_buffer->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
795 /* Increases or decreases the packet length.
796 * It does not allocate or deallocate new buffers.
797 * Therefore, the added length must be compatible
798 * with the last buffer. */
800 vlib_buffer_chain_increase_length (vlib_buffer_t * first,
801 vlib_buffer_t * last, i32 len)
803 last->current_length += len;
805 first->total_length_not_including_first_buffer += len;
808 /* Copy data to the end of the packet and increases its length.
809 * It does not allocate new buffers.
810 * Returns the number of copied bytes. */
812 vlib_buffer_chain_append_data (vlib_main_t * vm,
813 vlib_buffer_free_list_index_t free_list_index,
814 vlib_buffer_t * first,
815 vlib_buffer_t * last, void *data, u16 data_len)
818 vlib_buffer_free_list_buffer_size (vm, free_list_index);
819 ASSERT (n_buffer_bytes >= last->current_length + last->current_data);
820 u16 len = clib_min (data_len,
821 n_buffer_bytes - last->current_length -
823 clib_memcpy (vlib_buffer_get_current (last) + last->current_length, data,
825 vlib_buffer_chain_increase_length (first, last, len);
829 /* Copy data to the end of the packet and increases its length.
830 * Allocates additional buffers from the free list if necessary.
831 * Returns the number of copied bytes.
832 * 'last' value is modified whenever new buffers are allocated and
833 * chained and points to the last buffer in the chain. */
835 vlib_buffer_chain_append_data_with_alloc (vlib_main_t * vm,
836 vlib_buffer_free_list_index_t
838 vlib_buffer_t * first,
839 vlib_buffer_t ** last, void *data,
841 void vlib_buffer_chain_validate (vlib_main_t * vm, vlib_buffer_t * first);
843 format_function_t format_vlib_buffer, format_vlib_buffer_and_data,
844 format_vlib_buffer_contents;
848 /* Vector of packet data. */
851 /* Number of buffers to allocate in each call to physmem
853 u32 min_n_buffers_each_physmem_alloc;
855 /* Buffer free list for this template. */
856 vlib_buffer_free_list_index_t free_list_index;
859 } vlib_packet_template_t;
861 void vlib_packet_template_get_packet_helper (vlib_main_t * vm,
862 vlib_packet_template_t * t);
864 void vlib_packet_template_init (vlib_main_t * vm,
865 vlib_packet_template_t * t,
867 uword n_packet_data_bytes,
868 uword min_n_buffers_each_physmem_alloc,
871 void *vlib_packet_template_get_packet (vlib_main_t * vm,
872 vlib_packet_template_t * t,
876 vlib_packet_template_free (vlib_main_t * vm, vlib_packet_template_t * t)
878 vec_free (t->packet_data);
882 unserialize_vlib_buffer_n_bytes (serialize_main_t * m)
884 serialize_stream_t *s = &m->stream;
885 vlib_serialize_buffer_main_t *sm
886 = uword_to_pointer (m->stream.data_function_opaque,
887 vlib_serialize_buffer_main_t *);
888 vlib_main_t *vm = sm->vlib_main;
891 n = s->n_buffer_bytes - s->current_buffer_index;
892 if (sm->last_buffer != ~0)
894 vlib_buffer_t *b = vlib_get_buffer (vm, sm->last_buffer);
895 while (b->flags & VLIB_BUFFER_NEXT_PRESENT)
897 b = vlib_get_buffer (vm, b->next_buffer);
898 n += b->current_length;
903 clib_fifo_foreach (f, sm->rx.buffer_fifo, ({
904 n += vlib_buffer_index_length_in_chain (vm, f[0]);
911 /* Set a buffer quickly into "uninitialized" state. We want this to
912 be extremely cheap and arrange for all fields that need to be
913 initialized to be in the first 128 bits of the buffer. */
915 vlib_buffer_init_for_free_list (vlib_buffer_t * dst,
916 vlib_buffer_free_list_t * fl)
918 vlib_buffer_t *src = &fl->buffer_init_template;
920 /* Make sure vlib_buffer_t is cacheline aligned and sized */
921 ASSERT (STRUCT_OFFSET_OF (vlib_buffer_t, cacheline0) == 0);
922 ASSERT (STRUCT_OFFSET_OF (vlib_buffer_t, cacheline1) ==
923 CLIB_CACHE_LINE_BYTES);
924 ASSERT (STRUCT_OFFSET_OF (vlib_buffer_t, cacheline2) ==
925 CLIB_CACHE_LINE_BYTES * 2);
927 /* Make sure buffer template is sane. */
928 ASSERT (fl->index == vlib_buffer_get_free_list_index (src));
930 clib_memcpy (STRUCT_MARK_PTR (dst, template_start),
931 STRUCT_MARK_PTR (src, template_start),
932 STRUCT_OFFSET_OF (vlib_buffer_t, template_end) -
933 STRUCT_OFFSET_OF (vlib_buffer_t, template_start));
935 /* Not in the first 16 octets. */
936 dst->n_add_refs = src->n_add_refs;
937 vlib_buffer_set_free_list_index (dst, fl->index);
939 /* Make sure it really worked. */
940 #define _(f) ASSERT (dst->f == src->f);
945 /* ASSERT (dst->total_length_not_including_first_buffer == 0); */
946 /* total_length_not_including_first_buffer is not in the template anymore
947 * so it may actually not zeroed for some buffers. One option is to
948 * uncomment the line lower (comes at a cost), the other, is to just not
950 /* dst->total_length_not_including_first_buffer = 0; */
951 ASSERT (dst->n_add_refs == 0);
955 vlib_buffer_add_to_free_list (vlib_main_t * vm,
956 vlib_buffer_free_list_t * f,
957 u32 buffer_index, u8 do_init)
960 b = vlib_get_buffer (vm, buffer_index);
961 if (PREDICT_TRUE (do_init))
962 vlib_buffer_init_for_free_list (b, f);
963 vec_add1_aligned (f->buffers, buffer_index, CLIB_CACHE_LINE_BYTES);
965 if (vec_len (f->buffers) > 4 * VLIB_FRAME_SIZE)
967 vlib_buffer_free_list_t *mf;
968 mf = vlib_buffer_get_free_list (vlib_mains[0], f->index);
969 clib_spinlock_lock (&mf->global_buffers_lock);
970 /* keep last stored buffers, as they are more likely hot in the cache */
971 vec_add_aligned (mf->global_buffers, f->buffers, VLIB_FRAME_SIZE,
972 CLIB_CACHE_LINE_BYTES);
973 vec_delete (f->buffers, VLIB_FRAME_SIZE, 0);
974 f->n_alloc -= VLIB_FRAME_SIZE;
975 clib_spinlock_unlock (&mf->global_buffers_lock);
980 extern u32 *vlib_buffer_state_validation_lock;
981 extern uword *vlib_buffer_state_validation_hash;
982 extern void *vlib_buffer_state_heap;
986 vlib_validate_buffer_in_use (vlib_buffer_t * b, u32 expected)
992 oldheap = clib_mem_set_heap (vlib_buffer_state_heap);
994 while (__sync_lock_test_and_set (vlib_buffer_state_validation_lock, 1))
997 p = hash_get (vlib_buffer_state_validation_hash, b);
999 /* If we don't know about b, declare it to be in the expected state */
1002 hash_set (vlib_buffer_state_validation_hash, b, expected);
1006 if (p[0] != expected)
1008 void cj_stop (void);
1010 vlib_main_t *vm = &vlib_global_main;
1014 bi = vlib_get_buffer_index (vm, b);
1016 clib_mem_set_heap (oldheap);
1017 clib_warning ("%.6f buffer %llx (%d): %s, not %s",
1018 vlib_time_now (vm), bi,
1019 p[0] ? "busy" : "free", expected ? "busy" : "free");
1023 CLIB_MEMORY_BARRIER ();
1024 *vlib_buffer_state_validation_lock = 0;
1025 clib_mem_set_heap (oldheap);
1030 vlib_validate_buffer_set_in_use (vlib_buffer_t * b, u32 expected)
1035 oldheap = clib_mem_set_heap (vlib_buffer_state_heap);
1037 while (__sync_lock_test_and_set (vlib_buffer_state_validation_lock, 1))
1040 hash_set (vlib_buffer_state_validation_hash, b, expected);
1042 CLIB_MEMORY_BARRIER ();
1043 *vlib_buffer_state_validation_lock = 0;
1044 clib_mem_set_heap (oldheap);
1048 /** minimum data size of first buffer in a buffer chain */
1049 #define VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE (256)
1052 * @brief compress buffer chain in a way where the first buffer is at least
1053 * VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE long
1055 * @param[in] vm - vlib_main
1056 * @param[in,out] first - first buffer in chain
1057 * @param[in,out] discard_vector - vector of buffer indexes which were removed
1061 vlib_buffer_chain_compress (vlib_main_t * vm,
1062 vlib_buffer_t * first, u32 ** discard_vector)
1064 if (first->current_length >= VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE ||
1065 !(first->flags & VLIB_BUFFER_NEXT_PRESENT))
1067 /* this is already big enough or not a chain */
1070 /* probe free list to find allocated buffer size to avoid overfill */
1071 vlib_buffer_free_list_index_t index;
1072 vlib_buffer_free_list_t *free_list =
1073 vlib_buffer_get_buffer_free_list (vm, first, &index);
1075 u32 want_first_size = clib_min (VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE,
1076 free_list->n_data_bytes -
1077 first->current_data);
1080 vlib_buffer_t *second = vlib_get_buffer (vm, first->next_buffer);
1081 u32 need = want_first_size - first->current_length;
1082 u32 amount_to_copy = clib_min (need, second->current_length);
1083 clib_memcpy (((u8 *) vlib_buffer_get_current (first)) +
1084 first->current_length,
1085 vlib_buffer_get_current (second), amount_to_copy);
1086 first->current_length += amount_to_copy;
1087 vlib_buffer_advance (second, amount_to_copy);
1088 if (first->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID)
1090 first->total_length_not_including_first_buffer -= amount_to_copy;
1092 if (!second->current_length)
1094 vec_add1 (*discard_vector, first->next_buffer);
1095 if (second->flags & VLIB_BUFFER_NEXT_PRESENT)
1097 first->next_buffer = second->next_buffer;
1101 first->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
1103 second->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
1106 while ((first->current_length < want_first_size) &&
1107 (first->flags & VLIB_BUFFER_NEXT_PRESENT));
1110 #endif /* included_vlib_buffer_funcs_h */
1113 * fd.io coding-style-patch-verification: ON
1116 * eval: (c-set-style "gnu")