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>
44 #include <vppinfra/fifo.h>
47 vlib buffer access methods.
51 /** \brief Translate buffer index into buffer pointer
53 @param vm - (vlib_main_t *) vlib main data structure pointer
54 @param buffer_index - (u32) buffer index
55 @return - (vlib_buffer_t *) buffer pointer
57 always_inline vlib_buffer_t *
58 vlib_get_buffer (vlib_main_t * vm, u32 buffer_index)
60 vlib_buffer_main_t *bm = vm->buffer_main;
61 uword offset = ((uword) buffer_index) << CLIB_LOG2_CACHE_LINE_BYTES;
62 ASSERT (offset < bm->buffer_mem_size);
64 return uword_to_pointer (bm->buffer_mem_start + offset, void *);
67 static_always_inline void
68 vlib_buffer_copy_indices (u32 * dst, u32 * src, u32 n_indices)
70 clib_memcpy_fast (dst, src, n_indices * sizeof (u32));
73 static_always_inline void
74 vlib_buffer_copy_template (vlib_buffer_t * b, vlib_buffer_t * bt)
76 clib_memcpy_fast (b, bt, STRUCT_OFFSET_OF (vlib_buffer_t, template_end));
79 /** \brief Translate array of buffer indices into buffer pointers with offset
81 @param vm - (vlib_main_t *) vlib main data structure pointer
82 @param bi - (u32 *) array of buffer indices
83 @param b - (void **) array to store buffer pointers
84 @param count - (uword) number of elements
85 @param offset - (i32) offset applied to each pointer
87 static_always_inline void
88 vlib_get_buffers_with_offset (vlib_main_t * vm, u32 * bi, void **b, int count,
91 uword buffer_mem_start = vm->buffer_main->buffer_mem_start;
92 #ifdef CLIB_HAVE_VEC256
93 u64x4 off = u64x4_splat (buffer_mem_start + offset);
94 /* if count is not const, compiler will not unroll while loop
95 se we maintain two-in-parallel variant */
98 u64x4 b0 = u32x4_extend_to_u64x4 (u32x4_load_unaligned (bi));
99 u64x4 b1 = u32x4_extend_to_u64x4 (u32x4_load_unaligned (bi + 4));
100 /* shift and add to get vlib_buffer_t pointer */
101 u64x4_store_unaligned ((b0 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b);
102 u64x4_store_unaligned ((b1 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b + 4);
110 #ifdef CLIB_HAVE_VEC256
111 u64x4 b0 = u32x4_extend_to_u64x4 (u32x4_load_unaligned (bi));
112 /* shift and add to get vlib_buffer_t pointer */
113 u64x4_store_unaligned ((b0 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b);
114 #elif defined (CLIB_HAVE_VEC128)
115 u64x2 off = u64x2_splat (buffer_mem_start + offset);
116 u32x4 bi4 = u32x4_load_unaligned (bi);
117 u64x2 b0 = u32x4_extend_to_u64x2 ((u32x4) bi4);
118 #if defined (__aarch64__)
119 u64x2 b1 = u32x4_extend_to_u64x2_high ((u32x4) bi4);
121 bi4 = u32x4_shuffle (bi4, 2, 3, 0, 1);
122 u64x2 b1 = u32x4_extend_to_u64x2 ((u32x4) bi4);
124 u64x2_store_unaligned ((b0 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b);
125 u64x2_store_unaligned ((b1 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b + 2);
127 b[0] = ((u8 *) vlib_get_buffer (vm, bi[0])) + offset;
128 b[1] = ((u8 *) vlib_get_buffer (vm, bi[1])) + offset;
129 b[2] = ((u8 *) vlib_get_buffer (vm, bi[2])) + offset;
130 b[3] = ((u8 *) vlib_get_buffer (vm, bi[3])) + offset;
138 b[0] = ((u8 *) vlib_get_buffer (vm, bi[0])) + offset;
145 /** \brief Translate array of buffer indices into buffer pointers
147 @param vm - (vlib_main_t *) vlib main data structure pointer
148 @param bi - (u32 *) array of buffer indices
149 @param b - (vlib_buffer_t **) array to store buffer pointers
150 @param count - (uword) number of elements
153 static_always_inline void
154 vlib_get_buffers (vlib_main_t * vm, u32 * bi, vlib_buffer_t ** b, int count)
156 vlib_get_buffers_with_offset (vm, bi, (void **) b, count, 0);
159 /** \brief Translate buffer pointer into buffer index
161 @param vm - (vlib_main_t *) vlib main data structure pointer
162 @param p - (void *) buffer pointer
163 @return - (u32) buffer index
167 vlib_get_buffer_index (vlib_main_t * vm, void *p)
169 vlib_buffer_main_t *bm = vm->buffer_main;
170 uword offset = pointer_to_uword (p) - bm->buffer_mem_start;
171 ASSERT (pointer_to_uword (p) >= bm->buffer_mem_start);
172 ASSERT (offset < bm->buffer_mem_size);
173 ASSERT ((offset % (1 << CLIB_LOG2_CACHE_LINE_BYTES)) == 0);
174 return offset >> CLIB_LOG2_CACHE_LINE_BYTES;
177 /** \brief Translate array of buffer pointers into buffer indices with offset
179 @param vm - (vlib_main_t *) vlib main data structure pointer
180 @param b - (void **) array of buffer pointers
181 @param bi - (u32 *) array to store buffer indices
182 @param count - (uword) number of elements
183 @param offset - (i32) offset applied to each pointer
185 static_always_inline void
186 vlib_get_buffer_indices_with_offset (vlib_main_t * vm, void **b, u32 * bi,
187 uword count, i32 offset)
189 #ifdef CLIB_HAVE_VEC256
190 u32x8 mask = { 0, 2, 4, 6, 1, 3, 5, 7 };
191 u64x4 off4 = u64x4_splat (vm->buffer_main->buffer_mem_start - offset);
195 /* load 4 pointers into 256-bit register */
196 u64x4 v0 = u64x4_load_unaligned (b);
197 u64x4 v1 = u64x4_load_unaligned (b + 4);
203 v0 >>= CLIB_LOG2_CACHE_LINE_BYTES;
204 v1 >>= CLIB_LOG2_CACHE_LINE_BYTES;
206 /* permute 256-bit register so lower u32s of each buffer index are
207 * placed into lower 128-bits */
208 v2 = u32x8_permute ((u32x8) v0, mask);
209 v3 = u32x8_permute ((u32x8) v1, mask);
211 /* extract lower 128-bits and save them to the array of buffer indices */
212 u32x4_store_unaligned (u32x8_extract_lo (v2), bi);
213 u32x4_store_unaligned (u32x8_extract_lo (v3), bi + 4);
221 /* equivalent non-nector implementation */
222 bi[0] = vlib_get_buffer_index (vm, ((u8 *) b[0]) + offset);
223 bi[1] = vlib_get_buffer_index (vm, ((u8 *) b[1]) + offset);
224 bi[2] = vlib_get_buffer_index (vm, ((u8 *) b[2]) + offset);
225 bi[3] = vlib_get_buffer_index (vm, ((u8 *) b[3]) + offset);
232 bi[0] = vlib_get_buffer_index (vm, ((u8 *) b[0]) + offset);
239 /** \brief Translate array of buffer pointers into buffer indices
241 @param vm - (vlib_main_t *) vlib main data structure pointer
242 @param b - (vlib_buffer_t **) array of buffer pointers
243 @param bi - (u32 *) array to store buffer indices
244 @param count - (uword) number of elements
246 static_always_inline void
247 vlib_get_buffer_indices (vlib_main_t * vm, vlib_buffer_t ** b, u32 * bi,
250 vlib_get_buffer_indices_with_offset (vm, (void **) b, bi, count, 0);
253 /** \brief Get next buffer in buffer linklist, or zero for end of list.
255 @param vm - (vlib_main_t *) vlib main data structure pointer
256 @param b - (void *) buffer pointer
257 @return - (vlib_buffer_t *) next buffer, or NULL
259 always_inline vlib_buffer_t *
260 vlib_get_next_buffer (vlib_main_t * vm, vlib_buffer_t * b)
262 return (b->flags & VLIB_BUFFER_NEXT_PRESENT
263 ? vlib_get_buffer (vm, b->next_buffer) : 0);
266 uword vlib_buffer_length_in_chain_slow_path (vlib_main_t * vm,
267 vlib_buffer_t * b_first);
269 /** \brief Get length in bytes of the buffer chain
271 @param vm - (vlib_main_t *) vlib main data structure pointer
272 @param b - (void *) buffer pointer
273 @return - (uword) length of buffer chain
276 vlib_buffer_length_in_chain (vlib_main_t * vm, vlib_buffer_t * b)
278 uword len = b->current_length;
280 if (PREDICT_TRUE ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0))
283 if (PREDICT_TRUE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID))
284 return len + b->total_length_not_including_first_buffer;
286 return vlib_buffer_length_in_chain_slow_path (vm, b);
289 /** \brief Get length in bytes of the buffer index buffer chain
291 @param vm - (vlib_main_t *) vlib main data structure pointer
292 @param bi - (u32) buffer index
293 @return - (uword) length of buffer chain
296 vlib_buffer_index_length_in_chain (vlib_main_t * vm, u32 bi)
298 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
299 return vlib_buffer_length_in_chain (vm, b);
302 /** \brief Copy buffer contents to memory
304 @param vm - (vlib_main_t *) vlib main data structure pointer
305 @param buffer_index - (u32) buffer index
306 @param contents - (u8 *) memory, <strong>must be large enough</strong>
307 @return - (uword) length of buffer chain
310 vlib_buffer_contents (vlib_main_t * vm, u32 buffer_index, u8 * contents)
312 uword content_len = 0;
318 b = vlib_get_buffer (vm, buffer_index);
319 l = b->current_length;
320 clib_memcpy_fast (contents + content_len, b->data + b->current_data, l);
322 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
324 buffer_index = b->next_buffer;
331 vlib_buffer_get_pa (vlib_main_t * vm, vlib_buffer_t * b)
333 return vlib_physmem_get_pa (vm, b->data);
337 vlib_buffer_get_current_pa (vlib_main_t * vm, vlib_buffer_t * b)
339 return vlib_buffer_get_pa (vm, b) + b->current_data;
342 /** \brief Prefetch buffer metadata by buffer index
343 The first 64 bytes of buffer contains most header information
345 @param vm - (vlib_main_t *) vlib main data structure pointer
346 @param bi - (u32) buffer index
347 @param type - LOAD, STORE. In most cases, STORE is the right answer
349 /* Prefetch buffer header given index. */
350 #define vlib_prefetch_buffer_with_index(vm,bi,type) \
352 vlib_buffer_t * _b = vlib_get_buffer (vm, bi); \
353 vlib_prefetch_buffer_header (_b, type); \
358 /* Index is unknown. */
361 /* Index is known and free/allocated. */
362 VLIB_BUFFER_KNOWN_FREE,
363 VLIB_BUFFER_KNOWN_ALLOCATED,
364 } vlib_buffer_known_state_t;
366 void vlib_buffer_validate_alloc_free (vlib_main_t * vm, u32 * buffers,
368 vlib_buffer_known_state_t
371 always_inline vlib_buffer_known_state_t
372 vlib_buffer_is_known (vlib_main_t * vm, u32 buffer_index)
374 vlib_buffer_main_t *bm = vm->buffer_main;
376 clib_spinlock_lock (&bm->buffer_known_hash_lockp);
377 uword *p = hash_get (bm->buffer_known_hash, buffer_index);
378 clib_spinlock_unlock (&bm->buffer_known_hash_lockp);
379 return p ? p[0] : VLIB_BUFFER_UNKNOWN;
383 vlib_buffer_set_known_state (vlib_main_t * vm, u32 buffer_index,
384 vlib_buffer_known_state_t state)
386 vlib_buffer_main_t *bm = vm->buffer_main;
388 clib_spinlock_lock (&bm->buffer_known_hash_lockp);
389 hash_set (bm->buffer_known_hash, buffer_index, state);
390 clib_spinlock_unlock (&bm->buffer_known_hash_lockp);
393 /* Validates sanity of a single buffer.
394 Returns format'ed vector with error message if any. */
395 u8 *vlib_validate_buffer (vlib_main_t * vm, u32 buffer_index,
399 vlib_buffer_round_size (u32 size)
401 return round_pow2 (size, sizeof (vlib_buffer_t));
404 /** \brief Allocate buffers from specific freelist into supplied array
406 @param vm - (vlib_main_t *) vlib main data structure pointer
407 @param buffers - (u32 * ) buffer index array
408 @param n_buffers - (u32) number of buffers requested
409 @return - (u32) number of buffers actually allocated, may be
410 less than the number requested or zero
413 vlib_buffer_alloc_from_free_list (vlib_main_t * vm,
416 vlib_buffer_free_list_index_t index)
418 vlib_buffer_free_list_t *fl;
419 vlib_buffer_main_t *bm = vm->buffer_main;
423 ASSERT (bm->cb.vlib_buffer_fill_free_list_cb);
425 fl = pool_elt_at_index (vm->buffer_free_list_pool, index);
427 len = vec_len (fl->buffers);
429 if (PREDICT_FALSE (len < n_buffers))
431 bm->cb.vlib_buffer_fill_free_list_cb (vm, fl, n_buffers);
432 if (PREDICT_FALSE ((len = vec_len (fl->buffers)) == 0))
435 /* even if fill free list didn't manage to refill free list
436 we should give what we have */
437 n_buffers = clib_min (len, n_buffers);
439 /* following code is intentionaly duplicated to allow compiler
440 to optimize fast path when n_buffers is constant value */
441 src = fl->buffers + len - n_buffers;
442 vlib_buffer_copy_indices (buffers, src, n_buffers);
443 _vec_len (fl->buffers) -= n_buffers;
445 /* Verify that buffers are known free. */
446 vlib_buffer_validate_alloc_free (vm, buffers, n_buffers,
447 VLIB_BUFFER_KNOWN_FREE);
452 src = fl->buffers + len - n_buffers;
453 vlib_buffer_copy_indices (buffers, src, n_buffers);
454 _vec_len (fl->buffers) -= n_buffers;
456 /* Verify that buffers are known free. */
457 vlib_buffer_validate_alloc_free (vm, buffers, n_buffers,
458 VLIB_BUFFER_KNOWN_FREE);
463 /** \brief Allocate buffers into supplied array
465 @param vm - (vlib_main_t *) vlib main data structure pointer
466 @param buffers - (u32 * ) buffer index array
467 @param n_buffers - (u32) number of buffers requested
468 @return - (u32) number of buffers actually allocated, may be
469 less than the number requested or zero
472 vlib_buffer_alloc (vlib_main_t * vm, u32 * buffers, u32 n_buffers)
474 return vlib_buffer_alloc_from_free_list (vm, buffers, n_buffers,
475 VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);
478 /** \brief Allocate buffers into ring
480 @param vm - (vlib_main_t *) vlib main data structure pointer
481 @param buffers - (u32 * ) buffer index ring
482 @param start - (u32) first slot in the ring
483 @param ring_size - (u32) ring size
484 @param n_buffers - (u32) number of buffers requested
485 @return - (u32) number of buffers actually allocated, may be
486 less than the number requested or zero
489 vlib_buffer_alloc_to_ring (vlib_main_t * vm, u32 * ring, u32 start,
490 u32 ring_size, u32 n_buffers)
494 ASSERT (n_buffers <= ring_size);
496 if (PREDICT_TRUE (start + n_buffers <= ring_size))
497 return vlib_buffer_alloc (vm, ring + start, n_buffers);
499 n_alloc = vlib_buffer_alloc (vm, ring + start, ring_size - start);
501 if (PREDICT_TRUE (n_alloc == ring_size - start))
502 n_alloc += vlib_buffer_alloc (vm, ring, n_buffers - n_alloc);
507 /** \brief Free buffers
508 Frees the entire buffer chain for each buffer
510 @param vm - (vlib_main_t *) vlib main data structure pointer
511 @param buffers - (u32 * ) buffer index array
512 @param n_buffers - (u32) number of buffers to free
516 vlib_buffer_free (vlib_main_t * vm,
517 /* pointer to first buffer */
519 /* number of buffers to free */
522 vlib_buffer_main_t *bm = vm->buffer_main;
524 ASSERT (bm->cb.vlib_buffer_free_cb);
526 return bm->cb.vlib_buffer_free_cb (vm, buffers, n_buffers);
529 /** \brief Free buffers, does not free the buffer chain for each buffer
531 @param vm - (vlib_main_t *) vlib main data structure pointer
532 @param buffers - (u32 * ) buffer index array
533 @param n_buffers - (u32) number of buffers to free
537 vlib_buffer_free_no_next (vlib_main_t * vm,
538 /* pointer to first buffer */
540 /* number of buffers to free */
543 vlib_buffer_main_t *bm = vm->buffer_main;
545 ASSERT (bm->cb.vlib_buffer_free_no_next_cb);
547 return bm->cb.vlib_buffer_free_no_next_cb (vm, buffers, n_buffers);
550 /** \brief Free one buffer
551 Shorthand to free a single buffer chain.
553 @param vm - (vlib_main_t *) vlib main data structure pointer
554 @param buffer_index - (u32) buffer index to free
557 vlib_buffer_free_one (vlib_main_t * vm, u32 buffer_index)
559 vlib_buffer_free (vm, &buffer_index, /* n_buffers */ 1);
562 /** \brief Free buffers from ring
564 @param vm - (vlib_main_t *) vlib main data structure pointer
565 @param buffers - (u32 * ) buffer index ring
566 @param start - (u32) first slot in the ring
567 @param ring_size - (u32) ring size
568 @param n_buffers - (u32) number of buffers
571 vlib_buffer_free_from_ring (vlib_main_t * vm, u32 * ring, u32 start,
572 u32 ring_size, u32 n_buffers)
574 ASSERT (n_buffers <= ring_size);
576 if (PREDICT_TRUE (start + n_buffers <= ring_size))
578 vlib_buffer_free (vm, ring + start, n_buffers);
582 vlib_buffer_free (vm, ring + start, ring_size - start);
583 vlib_buffer_free (vm, ring, n_buffers - (ring_size - start));
587 /** \brief Free buffers from ring without freeing tail buffers
589 @param vm - (vlib_main_t *) vlib main data structure pointer
590 @param buffers - (u32 * ) buffer index ring
591 @param start - (u32) first slot in the ring
592 @param ring_size - (u32) ring size
593 @param n_buffers - (u32) number of buffers
596 vlib_buffer_free_from_ring_no_next (vlib_main_t * vm, u32 * ring, u32 start,
597 u32 ring_size, u32 n_buffers)
599 ASSERT (n_buffers <= ring_size);
601 if (PREDICT_TRUE (start + n_buffers <= ring_size))
603 vlib_buffer_free_no_next (vm, ring + start, n_buffers);
607 vlib_buffer_free_no_next (vm, ring + start, ring_size - start);
608 vlib_buffer_free_no_next (vm, ring, n_buffers - (ring_size - start));
612 /* Add/delete buffer free lists. */
613 vlib_buffer_free_list_index_t vlib_buffer_create_free_list (vlib_main_t * vm,
617 /* Append given data to end of buffer, possibly allocating new buffers. */
618 int vlib_buffer_add_data (vlib_main_t * vm, u32 * buffer_index, void *data,
621 /* duplicate all buffers in chain */
622 always_inline vlib_buffer_t *
623 vlib_buffer_copy (vlib_main_t * vm, vlib_buffer_t * b)
625 vlib_buffer_t *s, *d, *fd;
626 uword n_alloc, n_buffers = 1;
627 u32 flag_mask = VLIB_BUFFER_NEXT_PRESENT | VLIB_BUFFER_TOTAL_LENGTH_VALID;
631 while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
634 s = vlib_get_buffer (vm, s->next_buffer);
636 u32 new_buffers[n_buffers];
638 n_alloc = vlib_buffer_alloc (vm, new_buffers, n_buffers);
640 /* No guarantee that we'll get all the buffers we asked for */
641 if (PREDICT_FALSE (n_alloc < n_buffers))
644 vlib_buffer_free (vm, new_buffers, n_alloc);
650 fd = d = vlib_get_buffer (vm, new_buffers[0]);
651 d->current_data = s->current_data;
652 d->current_length = s->current_length;
653 d->flags = s->flags & flag_mask;
654 d->total_length_not_including_first_buffer =
655 s->total_length_not_including_first_buffer;
656 clib_memcpy_fast (d->opaque, s->opaque, sizeof (s->opaque));
657 clib_memcpy_fast (d->opaque2, s->opaque2, sizeof (s->opaque2));
658 clib_memcpy_fast (vlib_buffer_get_current (d),
659 vlib_buffer_get_current (s), s->current_length);
662 for (i = 1; i < n_buffers; i++)
665 d->next_buffer = new_buffers[i];
667 s = vlib_get_buffer (vm, s->next_buffer);
668 d = vlib_get_buffer (vm, new_buffers[i]);
669 d->current_data = s->current_data;
670 d->current_length = s->current_length;
671 clib_memcpy_fast (vlib_buffer_get_current (d),
672 vlib_buffer_get_current (s), s->current_length);
673 d->flags = s->flags & flag_mask;
679 /** \brief Create a maximum of 256 clones of buffer and store them
680 in the supplied array
682 @param vm - (vlib_main_t *) vlib main data structure pointer
683 @param src_buffer - (u32) source buffer index
684 @param buffers - (u32 * ) buffer index array
685 @param n_buffers - (u16) number of buffer clones requested (<=256)
686 @param head_end_offset - (u16) offset relative to current position
687 where packet head ends
688 @return - (u16) number of buffers actually cloned, may be
689 less than the number requested or zero
692 vlib_buffer_clone_256 (vlib_main_t * vm, u32 src_buffer, u32 * buffers,
693 u16 n_buffers, u16 head_end_offset)
696 vlib_buffer_t *s = vlib_get_buffer (vm, src_buffer);
698 ASSERT (s->n_add_refs == 0);
700 ASSERT (n_buffers <= 256);
702 if (s->current_length <= head_end_offset + CLIB_CACHE_LINE_BYTES * 2)
704 buffers[0] = src_buffer;
705 for (i = 1; i < n_buffers; i++)
708 d = vlib_buffer_copy (vm, s);
711 buffers[i] = vlib_get_buffer_index (vm, d);
717 if (PREDICT_FALSE (n_buffers == 1))
719 buffers[0] = src_buffer;
723 n_buffers = vlib_buffer_alloc (vm, buffers, n_buffers);
725 for (i = 0; i < n_buffers; i++)
727 vlib_buffer_t *d = vlib_get_buffer (vm, buffers[i]);
728 d->current_data = s->current_data;
729 d->current_length = head_end_offset;
730 d->total_length_not_including_first_buffer = s->current_length -
732 if (PREDICT_FALSE (s->flags & VLIB_BUFFER_NEXT_PRESENT))
734 d->total_length_not_including_first_buffer +=
735 s->total_length_not_including_first_buffer;
737 d->flags = s->flags | VLIB_BUFFER_NEXT_PRESENT;
738 d->flags &= ~VLIB_BUFFER_EXT_HDR_VALID;
739 clib_memcpy_fast (d->opaque, s->opaque, sizeof (s->opaque));
740 clib_memcpy_fast (d->opaque2, s->opaque2, sizeof (s->opaque2));
741 clib_memcpy_fast (vlib_buffer_get_current (d),
742 vlib_buffer_get_current (s), head_end_offset);
743 d->next_buffer = src_buffer;
745 vlib_buffer_advance (s, head_end_offset);
746 s->n_add_refs = n_buffers - 1;
747 while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
749 s = vlib_get_buffer (vm, s->next_buffer);
750 s->n_add_refs = n_buffers - 1;
756 /** \brief Create multiple clones of buffer and store them
757 in the supplied array
759 @param vm - (vlib_main_t *) vlib main data structure pointer
760 @param src_buffer - (u32) source buffer index
761 @param buffers - (u32 * ) buffer index array
762 @param n_buffers - (u16) number of buffer clones requested (<=256)
763 @param head_end_offset - (u16) offset relative to current position
764 where packet head ends
765 @return - (u16) number of buffers actually cloned, may be
766 less than the number requested or zero
769 vlib_buffer_clone (vlib_main_t * vm, u32 src_buffer, u32 * buffers,
770 u16 n_buffers, u16 head_end_offset)
772 vlib_buffer_t *s = vlib_get_buffer (vm, src_buffer);
775 while (n_buffers > 256)
778 copy = vlib_buffer_copy (vm, s);
779 n_cloned += vlib_buffer_clone_256 (vm,
780 vlib_get_buffer_index (vm, copy),
781 (buffers + n_cloned),
782 256, head_end_offset);
785 n_cloned += vlib_buffer_clone_256 (vm, src_buffer,
787 n_buffers, head_end_offset);
792 /** \brief Attach cloned tail to the buffer
794 @param vm - (vlib_main_t *) vlib main data structure pointer
795 @param head - (vlib_buffer_t *) head buffer
796 @param tail - (Vlib buffer_t *) tail buffer to clone and attach to head
800 vlib_buffer_attach_clone (vlib_main_t * vm, vlib_buffer_t * head,
801 vlib_buffer_t * tail)
803 ASSERT ((head->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
805 head->flags |= VLIB_BUFFER_NEXT_PRESENT;
806 head->flags &= ~VLIB_BUFFER_TOTAL_LENGTH_VALID;
807 head->flags &= ~VLIB_BUFFER_EXT_HDR_VALID;
808 head->flags |= (tail->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID);
809 head->next_buffer = vlib_get_buffer_index (vm, tail);
810 head->total_length_not_including_first_buffer = tail->current_length +
811 tail->total_length_not_including_first_buffer;
814 clib_atomic_add_fetch (&tail->n_add_refs, 1);
816 if (tail->flags & VLIB_BUFFER_NEXT_PRESENT)
818 tail = vlib_get_buffer (vm, tail->next_buffer);
823 /* Initializes the buffer as an empty packet with no chained buffers. */
825 vlib_buffer_chain_init (vlib_buffer_t * first)
827 first->total_length_not_including_first_buffer = 0;
828 first->current_length = 0;
829 first->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
830 first->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
833 /* The provided next_bi buffer index is appended to the end of the packet. */
834 always_inline vlib_buffer_t *
835 vlib_buffer_chain_buffer (vlib_main_t * vm, vlib_buffer_t * last, u32 next_bi)
837 vlib_buffer_t *next_buffer = vlib_get_buffer (vm, next_bi);
838 last->next_buffer = next_bi;
839 last->flags |= VLIB_BUFFER_NEXT_PRESENT;
840 next_buffer->current_length = 0;
841 next_buffer->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
845 /* Increases or decreases the packet length.
846 * It does not allocate or deallocate new buffers.
847 * Therefore, the added length must be compatible
848 * with the last buffer. */
850 vlib_buffer_chain_increase_length (vlib_buffer_t * first,
851 vlib_buffer_t * last, i32 len)
853 last->current_length += len;
855 first->total_length_not_including_first_buffer += len;
858 /* Copy data to the end of the packet and increases its length.
859 * It does not allocate new buffers.
860 * Returns the number of copied bytes. */
862 vlib_buffer_chain_append_data (vlib_main_t * vm,
863 vlib_buffer_free_list_index_t free_list_index,
864 vlib_buffer_t * first,
865 vlib_buffer_t * last, void *data, u16 data_len)
867 u32 n_buffer_bytes = VLIB_BUFFER_DATA_SIZE;
868 ASSERT (n_buffer_bytes >= last->current_length + last->current_data);
869 u16 len = clib_min (data_len,
870 n_buffer_bytes - last->current_length -
872 clib_memcpy_fast (vlib_buffer_get_current (last) + last->current_length,
874 vlib_buffer_chain_increase_length (first, last, len);
878 /* Copy data to the end of the packet and increases its length.
879 * Allocates additional buffers from the free list if necessary.
880 * Returns the number of copied bytes.
881 * 'last' value is modified whenever new buffers are allocated and
882 * chained and points to the last buffer in the chain. */
884 vlib_buffer_chain_append_data_with_alloc (vlib_main_t * vm,
885 vlib_buffer_free_list_index_t
887 vlib_buffer_t * first,
888 vlib_buffer_t ** last, void *data,
890 void vlib_buffer_chain_validate (vlib_main_t * vm, vlib_buffer_t * first);
892 format_function_t format_vlib_buffer, format_vlib_buffer_and_data,
893 format_vlib_buffer_contents;
897 /* Vector of packet data. */
900 /* Number of buffers to allocate in each call to allocator. */
901 u32 min_n_buffers_each_alloc;
903 /* Buffer free list for this template. */
904 vlib_buffer_free_list_index_t free_list_index;
909 } vlib_packet_template_t;
911 void vlib_packet_template_get_packet_helper (vlib_main_t * vm,
912 vlib_packet_template_t * t);
914 void vlib_packet_template_init (vlib_main_t * vm,
915 vlib_packet_template_t * t,
917 uword n_packet_data_bytes,
918 uword min_n_buffers_each_alloc,
921 void *vlib_packet_template_get_packet (vlib_main_t * vm,
922 vlib_packet_template_t * t,
926 vlib_packet_template_free (vlib_main_t * vm, vlib_packet_template_t * t)
928 vec_free (t->packet_data);
931 static_always_inline vlib_buffer_pool_t *
932 vlib_buffer_pool_get (vlib_main_t * vm, u8 buffer_pool_index)
934 vlib_buffer_main_t *bm = vm->buffer_main;
935 return vec_elt_at_index (bm->buffer_pools, buffer_pool_index);
939 vlib_buffer_add_to_free_list (vlib_main_t * vm,
940 vlib_buffer_free_list_t * f,
941 u32 buffer_index, u8 do_init)
943 vlib_buffer_pool_t *bp = vlib_buffer_pool_get (vm, f->buffer_pool_index);
945 b = vlib_get_buffer (vm, buffer_index);
946 if (PREDICT_TRUE (do_init))
947 clib_memset (b, 0, STRUCT_OFFSET_OF (vlib_buffer_t, template_end));
948 vec_add1_aligned (f->buffers, buffer_index, CLIB_CACHE_LINE_BYTES);
950 if (vec_len (f->buffers) > 4 * VLIB_FRAME_SIZE)
952 clib_spinlock_lock (&bp->lock);
953 /* keep last stored buffers, as they are more likely hot in the cache */
954 vec_add_aligned (bp->buffers, f->buffers, VLIB_FRAME_SIZE,
955 CLIB_CACHE_LINE_BYTES);
956 vec_delete (f->buffers, VLIB_FRAME_SIZE, 0);
957 f->n_alloc -= VLIB_FRAME_SIZE;
958 clib_spinlock_unlock (&bp->lock);
963 extern u32 *vlib_buffer_state_validation_lock;
964 extern uword *vlib_buffer_state_validation_hash;
965 extern void *vlib_buffer_state_heap;
969 vlib_validate_buffer_in_use (vlib_buffer_t * b, u32 expected)
975 oldheap = clib_mem_set_heap (vlib_buffer_state_heap);
977 while (clib_atomic_test_and_set (vlib_buffer_state_validation_lock))
980 p = hash_get (vlib_buffer_state_validation_hash, b);
982 /* If we don't know about b, declare it to be in the expected state */
985 hash_set (vlib_buffer_state_validation_hash, b, expected);
989 if (p[0] != expected)
993 vlib_main_t *vm = &vlib_global_main;
997 bi = vlib_get_buffer_index (vm, b);
999 clib_mem_set_heap (oldheap);
1000 clib_warning ("%.6f buffer %llx (%d): %s, not %s",
1001 vlib_time_now (vm), bi,
1002 p[0] ? "busy" : "free", expected ? "busy" : "free");
1006 CLIB_MEMORY_BARRIER ();
1007 *vlib_buffer_state_validation_lock = 0;
1008 clib_mem_set_heap (oldheap);
1013 vlib_validate_buffer_set_in_use (vlib_buffer_t * b, u32 expected)
1018 oldheap = clib_mem_set_heap (vlib_buffer_state_heap);
1020 while (clib_atomic_test_and_set (vlib_buffer_state_validation_lock))
1023 hash_set (vlib_buffer_state_validation_hash, b, expected);
1025 CLIB_MEMORY_BARRIER ();
1026 *vlib_buffer_state_validation_lock = 0;
1027 clib_mem_set_heap (oldheap);
1031 /** minimum data size of first buffer in a buffer chain */
1032 #define VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE (256)
1035 * @brief compress buffer chain in a way where the first buffer is at least
1036 * VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE long
1038 * @param[in] vm - vlib_main
1039 * @param[in,out] first - first buffer in chain
1040 * @param[in,out] discard_vector - vector of buffer indexes which were removed
1044 vlib_buffer_chain_compress (vlib_main_t * vm,
1045 vlib_buffer_t * first, u32 ** discard_vector)
1047 if (first->current_length >= VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE ||
1048 !(first->flags & VLIB_BUFFER_NEXT_PRESENT))
1050 /* this is already big enough or not a chain */
1054 u32 want_first_size = clib_min (VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE,
1055 VLIB_BUFFER_DATA_SIZE -
1056 first->current_data);
1059 vlib_buffer_t *second = vlib_get_buffer (vm, first->next_buffer);
1060 u32 need = want_first_size - first->current_length;
1061 u32 amount_to_copy = clib_min (need, second->current_length);
1062 clib_memcpy_fast (((u8 *) vlib_buffer_get_current (first)) +
1063 first->current_length,
1064 vlib_buffer_get_current (second), amount_to_copy);
1065 first->current_length += amount_to_copy;
1066 second->current_data += amount_to_copy;
1067 second->current_length -= amount_to_copy;
1068 if (first->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID)
1070 first->total_length_not_including_first_buffer -= amount_to_copy;
1072 if (!second->current_length)
1074 vec_add1 (*discard_vector, first->next_buffer);
1075 if (second->flags & VLIB_BUFFER_NEXT_PRESENT)
1077 first->next_buffer = second->next_buffer;
1081 first->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
1083 second->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
1086 while ((first->current_length < want_first_size) &&
1087 (first->flags & VLIB_BUFFER_NEXT_PRESENT));
1091 * @brief linearize buffer chain - the first buffer is filled, if needed,
1092 * buffers are allocated and filled, returns free space in last buffer or
1093 * negative on failure
1095 * @param[in] vm - vlib_main
1096 * @param[in,out] first - first buffer in chain
1099 vlib_buffer_chain_linearize (vlib_main_t * vm, vlib_buffer_t * first)
1101 vlib_buffer_t *b = first;
1102 u32 buf_len = VLIB_BUFFER_DATA_SIZE;
1103 // free buffer chain starting from the second buffer
1104 int free_count = (b->flags & VLIB_BUFFER_NEXT_PRESENT) != 0;
1105 u32 chain_to_free = b->next_buffer;
1107 u32 len = vlib_buffer_length_in_chain (vm, b);
1108 u32 free_len = buf_len - b->current_data - b->current_length;
1109 int alloc_len = clib_max (len - free_len, 0); //use the free len in the first buffer
1110 int n_buffers = (alloc_len + buf_len - 1) / buf_len;
1111 u32 new_buffers[n_buffers];
1113 u32 n_alloc = vlib_buffer_alloc (vm, new_buffers, n_buffers);
1114 if (n_alloc != n_buffers)
1116 vlib_buffer_free_no_next (vm, new_buffers, n_alloc);
1120 vlib_buffer_t *s = b;
1121 while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
1123 s = vlib_get_buffer (vm, s->next_buffer);
1124 int d_free_len = buf_len - b->current_data - b->current_length;
1125 ASSERT (d_free_len >= 0);
1126 // chain buf and split write
1127 u32 copy_len = clib_min (d_free_len, s->current_length);
1128 u8 *d = vlib_buffer_put_uninit (b, copy_len);
1129 clib_memcpy (d, vlib_buffer_get_current (s), copy_len);
1130 int rest = s->current_length - copy_len;
1134 ASSERT (vlib_buffer_get_tail (b) == b->data + buf_len);
1135 ASSERT (n_buffers > 0);
1136 b = vlib_buffer_chain_buffer (vm, b, new_buffers[--n_buffers]);
1137 //make full use of the new buffers
1138 b->current_data = 0;
1139 d = vlib_buffer_put_uninit (b, rest);
1140 clib_memcpy (d, vlib_buffer_get_current (s) + copy_len, rest);
1143 vlib_buffer_free (vm, &chain_to_free, free_count);
1144 b->flags &= ~VLIB_BUFFER_TOTAL_LENGTH_VALID;
1145 if (b == first) /* no buffers addeed */
1146 b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
1147 ASSERT (len == vlib_buffer_length_in_chain (vm, first));
1148 ASSERT (n_buffers == 0);
1149 return buf_len - b->current_data - b->current_length;
1152 #endif /* included_vlib_buffer_funcs_h */
1155 * fd.io coding-style-patch-verification: ON
1158 * eval: (c-set-style "gnu")