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_ASSERT_OFFSET_OF (vlib_buffer_t, template_end, 64);
74 static_always_inline void
75 vlib_buffer_copy_template (vlib_buffer_t * b, vlib_buffer_t * bt)
77 #if defined CLIB_HAVE_VEC512
78 b->as_u8x64[0] = bt->as_u8x64[0];
79 #elif defined (CLIB_HAVE_VEC256)
80 b->as_u8x32[0] = bt->as_u8x32[0];
81 b->as_u8x32[1] = bt->as_u8x32[1];
82 #elif defined (CLIB_HAVE_VEC128)
83 b->as_u8x16[0] = bt->as_u8x16[0];
84 b->as_u8x16[1] = bt->as_u8x16[1];
85 b->as_u8x16[2] = bt->as_u8x16[2];
86 b->as_u8x16[3] = bt->as_u8x16[3];
88 clib_memcpy_fast (b, bt, 64);
92 /** \brief Translate array of buffer indices into buffer pointers with offset
94 @param vm - (vlib_main_t *) vlib main data structure pointer
95 @param bi - (u32 *) array of buffer indices
96 @param b - (void **) array to store buffer pointers
97 @param count - (uword) number of elements
98 @param offset - (i32) offset applied to each pointer
100 static_always_inline void
101 vlib_get_buffers_with_offset (vlib_main_t * vm, u32 * bi, void **b, int count,
104 uword buffer_mem_start = vm->buffer_main->buffer_mem_start;
105 #ifdef CLIB_HAVE_VEC256
106 u64x4 off = u64x4_splat (buffer_mem_start + offset);
107 /* if count is not const, compiler will not unroll while loop
108 se we maintain two-in-parallel variant */
111 u64x4 b0 = u32x4_extend_to_u64x4 (u32x4_load_unaligned (bi));
112 u64x4 b1 = u32x4_extend_to_u64x4 (u32x4_load_unaligned (bi + 4));
113 /* shift and add to get vlib_buffer_t pointer */
114 u64x4_store_unaligned ((b0 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b);
115 u64x4_store_unaligned ((b1 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b + 4);
123 #ifdef CLIB_HAVE_VEC256
124 u64x4 b0 = u32x4_extend_to_u64x4 (u32x4_load_unaligned (bi));
125 /* shift and add to get vlib_buffer_t pointer */
126 u64x4_store_unaligned ((b0 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b);
127 #elif defined (CLIB_HAVE_VEC128)
128 u64x2 off = u64x2_splat (buffer_mem_start + offset);
129 u32x4 bi4 = u32x4_load_unaligned (bi);
130 u64x2 b0 = u32x4_extend_to_u64x2 ((u32x4) bi4);
131 #if defined (__aarch64__)
132 u64x2 b1 = u32x4_extend_to_u64x2_high ((u32x4) bi4);
134 bi4 = u32x4_shuffle (bi4, 2, 3, 0, 1);
135 u64x2 b1 = u32x4_extend_to_u64x2 ((u32x4) bi4);
137 u64x2_store_unaligned ((b0 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b);
138 u64x2_store_unaligned ((b1 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b + 2);
140 b[0] = ((u8 *) vlib_get_buffer (vm, bi[0])) + offset;
141 b[1] = ((u8 *) vlib_get_buffer (vm, bi[1])) + offset;
142 b[2] = ((u8 *) vlib_get_buffer (vm, bi[2])) + offset;
143 b[3] = ((u8 *) vlib_get_buffer (vm, bi[3])) + offset;
151 b[0] = ((u8 *) vlib_get_buffer (vm, bi[0])) + offset;
158 /** \brief Translate array of buffer indices into buffer pointers
160 @param vm - (vlib_main_t *) vlib main data structure pointer
161 @param bi - (u32 *) array of buffer indices
162 @param b - (vlib_buffer_t **) array to store buffer pointers
163 @param count - (uword) number of elements
166 static_always_inline void
167 vlib_get_buffers (vlib_main_t * vm, u32 * bi, vlib_buffer_t ** b, int count)
169 vlib_get_buffers_with_offset (vm, bi, (void **) b, count, 0);
172 /** \brief Translate buffer pointer into buffer index
174 @param vm - (vlib_main_t *) vlib main data structure pointer
175 @param p - (void *) buffer pointer
176 @return - (u32) buffer index
180 vlib_get_buffer_index (vlib_main_t * vm, void *p)
182 vlib_buffer_main_t *bm = vm->buffer_main;
183 uword offset = pointer_to_uword (p) - bm->buffer_mem_start;
184 ASSERT (pointer_to_uword (p) >= bm->buffer_mem_start);
185 ASSERT (offset < bm->buffer_mem_size);
186 ASSERT ((offset % (1 << CLIB_LOG2_CACHE_LINE_BYTES)) == 0);
187 return offset >> CLIB_LOG2_CACHE_LINE_BYTES;
190 /** \brief Translate array of buffer pointers into buffer indices with offset
192 @param vm - (vlib_main_t *) vlib main data structure pointer
193 @param b - (void **) array of buffer pointers
194 @param bi - (u32 *) array to store buffer indices
195 @param count - (uword) number of elements
196 @param offset - (i32) offset applied to each pointer
198 static_always_inline void
199 vlib_get_buffer_indices_with_offset (vlib_main_t * vm, void **b, u32 * bi,
200 uword count, i32 offset)
202 #ifdef CLIB_HAVE_VEC256
203 u32x8 mask = { 0, 2, 4, 6, 1, 3, 5, 7 };
204 u64x4 off4 = u64x4_splat (vm->buffer_main->buffer_mem_start - offset);
208 /* load 4 pointers into 256-bit register */
209 u64x4 v0 = u64x4_load_unaligned (b);
210 u64x4 v1 = u64x4_load_unaligned (b + 4);
216 v0 >>= CLIB_LOG2_CACHE_LINE_BYTES;
217 v1 >>= CLIB_LOG2_CACHE_LINE_BYTES;
219 /* permute 256-bit register so lower u32s of each buffer index are
220 * placed into lower 128-bits */
221 v2 = u32x8_permute ((u32x8) v0, mask);
222 v3 = u32x8_permute ((u32x8) v1, mask);
224 /* extract lower 128-bits and save them to the array of buffer indices */
225 u32x4_store_unaligned (u32x8_extract_lo (v2), bi);
226 u32x4_store_unaligned (u32x8_extract_lo (v3), bi + 4);
234 /* equivalent non-nector implementation */
235 bi[0] = vlib_get_buffer_index (vm, ((u8 *) b[0]) + offset);
236 bi[1] = vlib_get_buffer_index (vm, ((u8 *) b[1]) + offset);
237 bi[2] = vlib_get_buffer_index (vm, ((u8 *) b[2]) + offset);
238 bi[3] = vlib_get_buffer_index (vm, ((u8 *) b[3]) + offset);
245 bi[0] = vlib_get_buffer_index (vm, ((u8 *) b[0]) + offset);
252 /** \brief Translate array of buffer pointers into buffer indices
254 @param vm - (vlib_main_t *) vlib main data structure pointer
255 @param b - (vlib_buffer_t **) array of buffer pointers
256 @param bi - (u32 *) array to store buffer indices
257 @param count - (uword) number of elements
259 static_always_inline void
260 vlib_get_buffer_indices (vlib_main_t * vm, vlib_buffer_t ** b, u32 * bi,
263 vlib_get_buffer_indices_with_offset (vm, (void **) b, bi, count, 0);
266 /** \brief Get next buffer in buffer linklist, or zero for end of list.
268 @param vm - (vlib_main_t *) vlib main data structure pointer
269 @param b - (void *) buffer pointer
270 @return - (vlib_buffer_t *) next buffer, or NULL
272 always_inline vlib_buffer_t *
273 vlib_get_next_buffer (vlib_main_t * vm, vlib_buffer_t * b)
275 return (b->flags & VLIB_BUFFER_NEXT_PRESENT
276 ? vlib_get_buffer (vm, b->next_buffer) : 0);
279 uword vlib_buffer_length_in_chain_slow_path (vlib_main_t * vm,
280 vlib_buffer_t * b_first);
282 /** \brief Get length in bytes of the buffer chain
284 @param vm - (vlib_main_t *) vlib main data structure pointer
285 @param b - (void *) buffer pointer
286 @return - (uword) length of buffer chain
289 vlib_buffer_length_in_chain (vlib_main_t * vm, vlib_buffer_t * b)
291 uword len = b->current_length;
293 if (PREDICT_TRUE ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0))
296 if (PREDICT_TRUE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID))
297 return len + b->total_length_not_including_first_buffer;
299 return vlib_buffer_length_in_chain_slow_path (vm, b);
302 /** \brief Get length in bytes of the buffer index buffer chain
304 @param vm - (vlib_main_t *) vlib main data structure pointer
305 @param bi - (u32) buffer index
306 @return - (uword) length of buffer chain
309 vlib_buffer_index_length_in_chain (vlib_main_t * vm, u32 bi)
311 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
312 return vlib_buffer_length_in_chain (vm, b);
315 /** \brief Copy buffer contents to memory
317 @param vm - (vlib_main_t *) vlib main data structure pointer
318 @param buffer_index - (u32) buffer index
319 @param contents - (u8 *) memory, <strong>must be large enough</strong>
320 @return - (uword) length of buffer chain
323 vlib_buffer_contents (vlib_main_t * vm, u32 buffer_index, u8 * contents)
325 uword content_len = 0;
331 b = vlib_get_buffer (vm, buffer_index);
332 l = b->current_length;
333 clib_memcpy_fast (contents + content_len, b->data + b->current_data, l);
335 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
337 buffer_index = b->next_buffer;
344 vlib_buffer_get_pa (vlib_main_t * vm, vlib_buffer_t * b)
346 return vlib_physmem_get_pa (vm, b->data);
350 vlib_buffer_get_current_pa (vlib_main_t * vm, vlib_buffer_t * b)
352 return vlib_buffer_get_pa (vm, b) + b->current_data;
355 /** \brief Prefetch buffer metadata by buffer index
356 The first 64 bytes of buffer contains most header information
358 @param vm - (vlib_main_t *) vlib main data structure pointer
359 @param bi - (u32) buffer index
360 @param type - LOAD, STORE. In most cases, STORE is the right answer
362 /* Prefetch buffer header given index. */
363 #define vlib_prefetch_buffer_with_index(vm,bi,type) \
365 vlib_buffer_t * _b = vlib_get_buffer (vm, bi); \
366 vlib_prefetch_buffer_header (_b, type); \
371 /* Index is unknown. */
374 /* Index is known and free/allocated. */
375 VLIB_BUFFER_KNOWN_FREE,
376 VLIB_BUFFER_KNOWN_ALLOCATED,
377 } vlib_buffer_known_state_t;
379 void vlib_buffer_validate_alloc_free (vlib_main_t * vm, u32 * buffers,
381 vlib_buffer_known_state_t
384 always_inline vlib_buffer_known_state_t
385 vlib_buffer_is_known (vlib_main_t * vm, u32 buffer_index)
387 vlib_buffer_main_t *bm = vm->buffer_main;
389 clib_spinlock_lock (&bm->buffer_known_hash_lockp);
390 uword *p = hash_get (bm->buffer_known_hash, buffer_index);
391 clib_spinlock_unlock (&bm->buffer_known_hash_lockp);
392 return p ? p[0] : VLIB_BUFFER_UNKNOWN;
396 vlib_buffer_set_known_state (vlib_main_t * vm, u32 buffer_index,
397 vlib_buffer_known_state_t state)
399 vlib_buffer_main_t *bm = vm->buffer_main;
401 clib_spinlock_lock (&bm->buffer_known_hash_lockp);
402 hash_set (bm->buffer_known_hash, buffer_index, state);
403 clib_spinlock_unlock (&bm->buffer_known_hash_lockp);
406 /* Validates sanity of a single buffer.
407 Returns format'ed vector with error message if any. */
408 u8 *vlib_validate_buffer (vlib_main_t * vm, u32 buffer_index,
412 vlib_buffer_round_size (u32 size)
414 return round_pow2 (size, sizeof (vlib_buffer_t));
417 /** \brief Allocate buffers from specific freelist into supplied array
419 @param vm - (vlib_main_t *) vlib main data structure pointer
420 @param buffers - (u32 * ) buffer index array
421 @param n_buffers - (u32) number of buffers requested
422 @return - (u32) number of buffers actually allocated, may be
423 less than the number requested or zero
426 vlib_buffer_alloc_from_free_list (vlib_main_t * vm,
429 vlib_buffer_free_list_index_t index)
431 vlib_buffer_free_list_t *fl;
432 vlib_buffer_main_t *bm = vm->buffer_main;
436 ASSERT (bm->cb.vlib_buffer_fill_free_list_cb);
438 fl = pool_elt_at_index (vm->buffer_free_list_pool, index);
440 len = vec_len (fl->buffers);
442 if (PREDICT_FALSE (len < n_buffers))
444 bm->cb.vlib_buffer_fill_free_list_cb (vm, fl, n_buffers);
445 if (PREDICT_FALSE ((len = vec_len (fl->buffers)) == 0))
448 /* even if fill free list didn't manage to refill free list
449 we should give what we have */
450 n_buffers = clib_min (len, n_buffers);
452 /* following code is intentionaly duplicated to allow compiler
453 to optimize fast path when n_buffers is constant value */
454 src = fl->buffers + len - n_buffers;
455 vlib_buffer_copy_indices (buffers, src, n_buffers);
456 _vec_len (fl->buffers) -= n_buffers;
458 /* Verify that buffers are known free. */
459 vlib_buffer_validate_alloc_free (vm, buffers, n_buffers,
460 VLIB_BUFFER_KNOWN_FREE);
465 src = fl->buffers + len - n_buffers;
466 vlib_buffer_copy_indices (buffers, src, n_buffers);
467 _vec_len (fl->buffers) -= n_buffers;
469 /* Verify that buffers are known free. */
470 vlib_buffer_validate_alloc_free (vm, buffers, n_buffers,
471 VLIB_BUFFER_KNOWN_FREE);
476 /** \brief Allocate buffers into supplied array
478 @param vm - (vlib_main_t *) vlib main data structure pointer
479 @param buffers - (u32 * ) buffer index array
480 @param n_buffers - (u32) number of buffers requested
481 @return - (u32) number of buffers actually allocated, may be
482 less than the number requested or zero
485 vlib_buffer_alloc (vlib_main_t * vm, u32 * buffers, u32 n_buffers)
487 return vlib_buffer_alloc_from_free_list (vm, buffers, n_buffers,
488 VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);
491 /** \brief Allocate buffers into ring
493 @param vm - (vlib_main_t *) vlib main data structure pointer
494 @param buffers - (u32 * ) buffer index ring
495 @param start - (u32) first slot in the ring
496 @param ring_size - (u32) ring size
497 @param n_buffers - (u32) number of buffers requested
498 @return - (u32) number of buffers actually allocated, may be
499 less than the number requested or zero
502 vlib_buffer_alloc_to_ring (vlib_main_t * vm, u32 * ring, u32 start,
503 u32 ring_size, u32 n_buffers)
507 ASSERT (n_buffers <= ring_size);
509 if (PREDICT_TRUE (start + n_buffers <= ring_size))
510 return vlib_buffer_alloc (vm, ring + start, n_buffers);
512 n_alloc = vlib_buffer_alloc (vm, ring + start, ring_size - start);
514 if (PREDICT_TRUE (n_alloc == ring_size - start))
515 n_alloc += vlib_buffer_alloc (vm, ring, n_buffers - n_alloc);
520 /** \brief Free buffers
521 Frees the entire buffer chain for each buffer
523 @param vm - (vlib_main_t *) vlib main data structure pointer
524 @param buffers - (u32 * ) buffer index array
525 @param n_buffers - (u32) number of buffers to free
529 vlib_buffer_free (vlib_main_t * vm,
530 /* pointer to first buffer */
532 /* number of buffers to free */
535 vlib_buffer_main_t *bm = vm->buffer_main;
537 ASSERT (bm->cb.vlib_buffer_free_cb);
539 return bm->cb.vlib_buffer_free_cb (vm, buffers, n_buffers);
542 /** \brief Free buffers, does not free the buffer chain for each buffer
544 @param vm - (vlib_main_t *) vlib main data structure pointer
545 @param buffers - (u32 * ) buffer index array
546 @param n_buffers - (u32) number of buffers to free
550 vlib_buffer_free_no_next (vlib_main_t * vm,
551 /* pointer to first buffer */
553 /* number of buffers to free */
556 vlib_buffer_main_t *bm = vm->buffer_main;
558 ASSERT (bm->cb.vlib_buffer_free_no_next_cb);
560 return bm->cb.vlib_buffer_free_no_next_cb (vm, buffers, n_buffers);
563 /** \brief Free one buffer
564 Shorthand to free a single buffer chain.
566 @param vm - (vlib_main_t *) vlib main data structure pointer
567 @param buffer_index - (u32) buffer index to free
570 vlib_buffer_free_one (vlib_main_t * vm, u32 buffer_index)
572 vlib_buffer_free (vm, &buffer_index, /* n_buffers */ 1);
575 /** \brief Free buffers from ring
577 @param vm - (vlib_main_t *) vlib main data structure pointer
578 @param buffers - (u32 * ) buffer index ring
579 @param start - (u32) first slot in the ring
580 @param ring_size - (u32) ring size
581 @param n_buffers - (u32) number of buffers
584 vlib_buffer_free_from_ring (vlib_main_t * vm, u32 * ring, u32 start,
585 u32 ring_size, u32 n_buffers)
587 ASSERT (n_buffers <= ring_size);
589 if (PREDICT_TRUE (start + n_buffers <= ring_size))
591 vlib_buffer_free (vm, ring + start, n_buffers);
595 vlib_buffer_free (vm, ring + start, ring_size - start);
596 vlib_buffer_free (vm, ring, n_buffers - (ring_size - start));
600 /** \brief Free buffers from ring without freeing tail buffers
602 @param vm - (vlib_main_t *) vlib main data structure pointer
603 @param buffers - (u32 * ) buffer index ring
604 @param start - (u32) first slot in the ring
605 @param ring_size - (u32) ring size
606 @param n_buffers - (u32) number of buffers
609 vlib_buffer_free_from_ring_no_next (vlib_main_t * vm, u32 * ring, u32 start,
610 u32 ring_size, u32 n_buffers)
612 ASSERT (n_buffers <= ring_size);
614 if (PREDICT_TRUE (start + n_buffers <= ring_size))
616 vlib_buffer_free_no_next (vm, ring + start, n_buffers);
620 vlib_buffer_free_no_next (vm, ring + start, ring_size - start);
621 vlib_buffer_free_no_next (vm, ring, n_buffers - (ring_size - start));
625 /* Add/delete buffer free lists. */
626 vlib_buffer_free_list_index_t vlib_buffer_create_free_list (vlib_main_t * vm,
630 /* Append given data to end of buffer, possibly allocating new buffers. */
631 int vlib_buffer_add_data (vlib_main_t * vm, u32 * buffer_index, void *data,
634 /* duplicate all buffers in chain */
635 always_inline vlib_buffer_t *
636 vlib_buffer_copy (vlib_main_t * vm, vlib_buffer_t * b)
638 vlib_buffer_t *s, *d, *fd;
639 uword n_alloc, n_buffers = 1;
640 u32 flag_mask = VLIB_BUFFER_NEXT_PRESENT | VLIB_BUFFER_TOTAL_LENGTH_VALID;
644 while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
647 s = vlib_get_buffer (vm, s->next_buffer);
649 u32 new_buffers[n_buffers];
651 n_alloc = vlib_buffer_alloc (vm, new_buffers, n_buffers);
653 /* No guarantee that we'll get all the buffers we asked for */
654 if (PREDICT_FALSE (n_alloc < n_buffers))
657 vlib_buffer_free (vm, new_buffers, n_alloc);
663 fd = d = vlib_get_buffer (vm, new_buffers[0]);
664 d->current_data = s->current_data;
665 d->current_length = s->current_length;
666 d->flags = s->flags & flag_mask;
667 d->total_length_not_including_first_buffer =
668 s->total_length_not_including_first_buffer;
669 clib_memcpy_fast (d->opaque, s->opaque, sizeof (s->opaque));
670 clib_memcpy_fast (d->opaque2, s->opaque2, sizeof (s->opaque2));
671 clib_memcpy_fast (vlib_buffer_get_current (d),
672 vlib_buffer_get_current (s), s->current_length);
675 for (i = 1; i < n_buffers; i++)
678 d->next_buffer = new_buffers[i];
680 s = vlib_get_buffer (vm, s->next_buffer);
681 d = vlib_get_buffer (vm, new_buffers[i]);
682 d->current_data = s->current_data;
683 d->current_length = s->current_length;
684 clib_memcpy_fast (vlib_buffer_get_current (d),
685 vlib_buffer_get_current (s), s->current_length);
686 d->flags = s->flags & flag_mask;
692 /** \brief Create a maximum of 256 clones of buffer and store them
693 in the supplied array
695 @param vm - (vlib_main_t *) vlib main data structure pointer
696 @param src_buffer - (u32) source buffer index
697 @param buffers - (u32 * ) buffer index array
698 @param n_buffers - (u16) number of buffer clones requested (<=256)
699 @param head_end_offset - (u16) offset relative to current position
700 where packet head ends
701 @return - (u16) number of buffers actually cloned, may be
702 less than the number requested or zero
705 vlib_buffer_clone_256 (vlib_main_t * vm, u32 src_buffer, u32 * buffers,
706 u16 n_buffers, u16 head_end_offset)
709 vlib_buffer_t *s = vlib_get_buffer (vm, src_buffer);
711 ASSERT (s->n_add_refs == 0);
713 ASSERT (n_buffers <= 256);
715 if (s->current_length <= head_end_offset + CLIB_CACHE_LINE_BYTES * 2)
717 buffers[0] = src_buffer;
718 for (i = 1; i < n_buffers; i++)
721 d = vlib_buffer_copy (vm, s);
724 buffers[i] = vlib_get_buffer_index (vm, d);
730 if (PREDICT_FALSE (n_buffers == 1))
732 buffers[0] = src_buffer;
736 n_buffers = vlib_buffer_alloc (vm, buffers, n_buffers);
738 for (i = 0; i < n_buffers; i++)
740 vlib_buffer_t *d = vlib_get_buffer (vm, buffers[i]);
741 d->current_data = s->current_data;
742 d->current_length = head_end_offset;
743 d->total_length_not_including_first_buffer = s->current_length -
745 if (PREDICT_FALSE (s->flags & VLIB_BUFFER_NEXT_PRESENT))
747 d->total_length_not_including_first_buffer +=
748 s->total_length_not_including_first_buffer;
750 d->flags = s->flags | VLIB_BUFFER_NEXT_PRESENT;
751 d->flags &= ~VLIB_BUFFER_EXT_HDR_VALID;
752 clib_memcpy_fast (d->opaque, s->opaque, sizeof (s->opaque));
753 clib_memcpy_fast (d->opaque2, s->opaque2, sizeof (s->opaque2));
754 clib_memcpy_fast (vlib_buffer_get_current (d),
755 vlib_buffer_get_current (s), head_end_offset);
756 d->next_buffer = src_buffer;
758 vlib_buffer_advance (s, head_end_offset);
759 s->n_add_refs = n_buffers - 1;
760 while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
762 s = vlib_get_buffer (vm, s->next_buffer);
763 s->n_add_refs = n_buffers - 1;
769 /** \brief Create multiple clones of buffer and store them
770 in the supplied array
772 @param vm - (vlib_main_t *) vlib main data structure pointer
773 @param src_buffer - (u32) source buffer index
774 @param buffers - (u32 * ) buffer index array
775 @param n_buffers - (u16) number of buffer clones requested (<=256)
776 @param head_end_offset - (u16) offset relative to current position
777 where packet head ends
778 @return - (u16) number of buffers actually cloned, may be
779 less than the number requested or zero
782 vlib_buffer_clone (vlib_main_t * vm, u32 src_buffer, u32 * buffers,
783 u16 n_buffers, u16 head_end_offset)
785 vlib_buffer_t *s = vlib_get_buffer (vm, src_buffer);
788 while (n_buffers > 256)
791 copy = vlib_buffer_copy (vm, s);
792 n_cloned += vlib_buffer_clone_256 (vm,
793 vlib_get_buffer_index (vm, copy),
794 (buffers + n_cloned),
795 256, head_end_offset);
798 n_cloned += vlib_buffer_clone_256 (vm, src_buffer,
800 n_buffers, head_end_offset);
805 /** \brief Attach cloned tail to the buffer
807 @param vm - (vlib_main_t *) vlib main data structure pointer
808 @param head - (vlib_buffer_t *) head buffer
809 @param tail - (Vlib buffer_t *) tail buffer to clone and attach to head
813 vlib_buffer_attach_clone (vlib_main_t * vm, vlib_buffer_t * head,
814 vlib_buffer_t * tail)
816 ASSERT ((head->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
818 head->flags |= VLIB_BUFFER_NEXT_PRESENT;
819 head->flags &= ~VLIB_BUFFER_TOTAL_LENGTH_VALID;
820 head->flags &= ~VLIB_BUFFER_EXT_HDR_VALID;
821 head->flags |= (tail->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID);
822 head->next_buffer = vlib_get_buffer_index (vm, tail);
823 head->total_length_not_including_first_buffer = tail->current_length +
824 tail->total_length_not_including_first_buffer;
827 clib_atomic_add_fetch (&tail->n_add_refs, 1);
829 if (tail->flags & VLIB_BUFFER_NEXT_PRESENT)
831 tail = vlib_get_buffer (vm, tail->next_buffer);
836 /* Initializes the buffer as an empty packet with no chained buffers. */
838 vlib_buffer_chain_init (vlib_buffer_t * first)
840 first->total_length_not_including_first_buffer = 0;
841 first->current_length = 0;
842 first->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
843 first->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
846 /* The provided next_bi buffer index is appended to the end of the packet. */
847 always_inline vlib_buffer_t *
848 vlib_buffer_chain_buffer (vlib_main_t * vm, vlib_buffer_t * last, u32 next_bi)
850 vlib_buffer_t *next_buffer = vlib_get_buffer (vm, next_bi);
851 last->next_buffer = next_bi;
852 last->flags |= VLIB_BUFFER_NEXT_PRESENT;
853 next_buffer->current_length = 0;
854 next_buffer->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
858 /* Increases or decreases the packet length.
859 * It does not allocate or deallocate new buffers.
860 * Therefore, the added length must be compatible
861 * with the last buffer. */
863 vlib_buffer_chain_increase_length (vlib_buffer_t * first,
864 vlib_buffer_t * last, i32 len)
866 last->current_length += len;
868 first->total_length_not_including_first_buffer += len;
871 /* Copy data to the end of the packet and increases its length.
872 * It does not allocate new buffers.
873 * Returns the number of copied bytes. */
875 vlib_buffer_chain_append_data (vlib_main_t * vm,
876 vlib_buffer_free_list_index_t free_list_index,
877 vlib_buffer_t * first,
878 vlib_buffer_t * last, void *data, u16 data_len)
880 u32 n_buffer_bytes = VLIB_BUFFER_DATA_SIZE;
881 ASSERT (n_buffer_bytes >= last->current_length + last->current_data);
882 u16 len = clib_min (data_len,
883 n_buffer_bytes - last->current_length -
885 clib_memcpy_fast (vlib_buffer_get_current (last) + last->current_length,
887 vlib_buffer_chain_increase_length (first, last, len);
891 /* Copy data to the end of the packet and increases its length.
892 * Allocates additional buffers from the free list if necessary.
893 * Returns the number of copied bytes.
894 * 'last' value is modified whenever new buffers are allocated and
895 * chained and points to the last buffer in the chain. */
897 vlib_buffer_chain_append_data_with_alloc (vlib_main_t * vm,
898 vlib_buffer_free_list_index_t
900 vlib_buffer_t * first,
901 vlib_buffer_t ** last, void *data,
903 void vlib_buffer_chain_validate (vlib_main_t * vm, vlib_buffer_t * first);
905 format_function_t format_vlib_buffer, format_vlib_buffer_and_data,
906 format_vlib_buffer_contents;
910 /* Vector of packet data. */
913 /* Number of buffers to allocate in each call to allocator. */
914 u32 min_n_buffers_each_alloc;
916 /* Buffer free list for this template. */
917 vlib_buffer_free_list_index_t free_list_index;
922 } vlib_packet_template_t;
924 void vlib_packet_template_get_packet_helper (vlib_main_t * vm,
925 vlib_packet_template_t * t);
927 void vlib_packet_template_init (vlib_main_t * vm,
928 vlib_packet_template_t * t,
930 uword n_packet_data_bytes,
931 uword min_n_buffers_each_alloc,
934 void *vlib_packet_template_get_packet (vlib_main_t * vm,
935 vlib_packet_template_t * t,
939 vlib_packet_template_free (vlib_main_t * vm, vlib_packet_template_t * t)
941 vec_free (t->packet_data);
944 static_always_inline vlib_buffer_pool_t *
945 vlib_buffer_pool_get (vlib_main_t * vm, u8 buffer_pool_index)
947 vlib_buffer_main_t *bm = vm->buffer_main;
948 return vec_elt_at_index (bm->buffer_pools, buffer_pool_index);
952 vlib_buffer_add_to_free_list (vlib_main_t * vm,
953 vlib_buffer_free_list_t * f,
954 u32 buffer_index, u8 do_init)
956 vlib_buffer_pool_t *bp = vlib_buffer_pool_get (vm, f->buffer_pool_index);
958 b = vlib_get_buffer (vm, buffer_index);
959 if (PREDICT_TRUE (do_init))
960 clib_memset (b, 0, STRUCT_OFFSET_OF (vlib_buffer_t, template_end));
961 vec_add1_aligned (f->buffers, buffer_index, CLIB_CACHE_LINE_BYTES);
963 if (vec_len (f->buffers) > 4 * VLIB_FRAME_SIZE)
965 clib_spinlock_lock (&bp->lock);
966 /* keep last stored buffers, as they are more likely hot in the cache */
967 vec_add_aligned (bp->buffers, f->buffers, VLIB_FRAME_SIZE,
968 CLIB_CACHE_LINE_BYTES);
969 vec_delete (f->buffers, VLIB_FRAME_SIZE, 0);
970 f->n_alloc -= VLIB_FRAME_SIZE;
971 clib_spinlock_unlock (&bp->lock);
976 extern u32 *vlib_buffer_state_validation_lock;
977 extern uword *vlib_buffer_state_validation_hash;
978 extern void *vlib_buffer_state_heap;
982 vlib_validate_buffer_in_use (vlib_buffer_t * b, u32 expected)
988 oldheap = clib_mem_set_heap (vlib_buffer_state_heap);
990 while (clib_atomic_test_and_set (vlib_buffer_state_validation_lock))
993 p = hash_get (vlib_buffer_state_validation_hash, b);
995 /* If we don't know about b, declare it to be in the expected state */
998 hash_set (vlib_buffer_state_validation_hash, b, expected);
1002 if (p[0] != expected)
1004 void cj_stop (void);
1006 vlib_main_t *vm = &vlib_global_main;
1010 bi = vlib_get_buffer_index (vm, b);
1012 clib_mem_set_heap (oldheap);
1013 clib_warning ("%.6f buffer %llx (%d): %s, not %s",
1014 vlib_time_now (vm), bi,
1015 p[0] ? "busy" : "free", expected ? "busy" : "free");
1019 CLIB_MEMORY_BARRIER ();
1020 *vlib_buffer_state_validation_lock = 0;
1021 clib_mem_set_heap (oldheap);
1026 vlib_validate_buffer_set_in_use (vlib_buffer_t * b, u32 expected)
1031 oldheap = clib_mem_set_heap (vlib_buffer_state_heap);
1033 while (clib_atomic_test_and_set (vlib_buffer_state_validation_lock))
1036 hash_set (vlib_buffer_state_validation_hash, b, expected);
1038 CLIB_MEMORY_BARRIER ();
1039 *vlib_buffer_state_validation_lock = 0;
1040 clib_mem_set_heap (oldheap);
1044 /** minimum data size of first buffer in a buffer chain */
1045 #define VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE (256)
1048 * @brief compress buffer chain in a way where the first buffer is at least
1049 * VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE long
1051 * @param[in] vm - vlib_main
1052 * @param[in,out] first - first buffer in chain
1053 * @param[in,out] discard_vector - vector of buffer indexes which were removed
1057 vlib_buffer_chain_compress (vlib_main_t * vm,
1058 vlib_buffer_t * first, u32 ** discard_vector)
1060 if (first->current_length >= VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE ||
1061 !(first->flags & VLIB_BUFFER_NEXT_PRESENT))
1063 /* this is already big enough or not a chain */
1067 u32 want_first_size = clib_min (VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE,
1068 VLIB_BUFFER_DATA_SIZE -
1069 first->current_data);
1072 vlib_buffer_t *second = vlib_get_buffer (vm, first->next_buffer);
1073 u32 need = want_first_size - first->current_length;
1074 u32 amount_to_copy = clib_min (need, second->current_length);
1075 clib_memcpy_fast (((u8 *) vlib_buffer_get_current (first)) +
1076 first->current_length,
1077 vlib_buffer_get_current (second), amount_to_copy);
1078 first->current_length += amount_to_copy;
1079 second->current_data += amount_to_copy;
1080 second->current_length -= amount_to_copy;
1081 if (first->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID)
1083 first->total_length_not_including_first_buffer -= amount_to_copy;
1085 if (!second->current_length)
1087 vec_add1 (*discard_vector, first->next_buffer);
1088 if (second->flags & VLIB_BUFFER_NEXT_PRESENT)
1090 first->next_buffer = second->next_buffer;
1094 first->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
1096 second->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
1099 while ((first->current_length < want_first_size) &&
1100 (first->flags & VLIB_BUFFER_NEXT_PRESENT));
1104 * @brief linearize buffer chain - the first buffer is filled, if needed,
1105 * buffers are allocated and filled, returns free space in last buffer or
1106 * negative on failure
1108 * @param[in] vm - vlib_main
1109 * @param[in,out] first - first buffer in chain
1112 vlib_buffer_chain_linearize (vlib_main_t * vm, vlib_buffer_t * first)
1114 vlib_buffer_t *b = first;
1115 u32 buf_len = VLIB_BUFFER_DATA_SIZE;
1116 // free buffer chain starting from the second buffer
1117 int free_count = (b->flags & VLIB_BUFFER_NEXT_PRESENT) != 0;
1118 u32 chain_to_free = b->next_buffer;
1120 u32 len = vlib_buffer_length_in_chain (vm, b);
1121 u32 free_len = buf_len - b->current_data - b->current_length;
1122 int alloc_len = clib_max (len - free_len, 0); //use the free len in the first buffer
1123 int n_buffers = (alloc_len + buf_len - 1) / buf_len;
1124 u32 new_buffers[n_buffers];
1126 u32 n_alloc = vlib_buffer_alloc (vm, new_buffers, n_buffers);
1127 if (n_alloc != n_buffers)
1129 vlib_buffer_free_no_next (vm, new_buffers, n_alloc);
1133 vlib_buffer_t *s = b;
1134 while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
1136 s = vlib_get_buffer (vm, s->next_buffer);
1137 int d_free_len = buf_len - b->current_data - b->current_length;
1138 ASSERT (d_free_len >= 0);
1139 // chain buf and split write
1140 u32 copy_len = clib_min (d_free_len, s->current_length);
1141 u8 *d = vlib_buffer_put_uninit (b, copy_len);
1142 clib_memcpy (d, vlib_buffer_get_current (s), copy_len);
1143 int rest = s->current_length - copy_len;
1147 ASSERT (vlib_buffer_get_tail (b) == b->data + buf_len);
1148 ASSERT (n_buffers > 0);
1149 b = vlib_buffer_chain_buffer (vm, b, new_buffers[--n_buffers]);
1150 //make full use of the new buffers
1151 b->current_data = 0;
1152 d = vlib_buffer_put_uninit (b, rest);
1153 clib_memcpy (d, vlib_buffer_get_current (s) + copy_len, rest);
1156 vlib_buffer_free (vm, &chain_to_free, free_count);
1157 b->flags &= ~VLIB_BUFFER_TOTAL_LENGTH_VALID;
1158 if (b == first) /* no buffers addeed */
1159 b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
1160 ASSERT (len == vlib_buffer_length_in_chain (vm, first));
1161 ASSERT (n_buffers == 0);
1162 return buf_len - b->current_data - b->current_length;
1165 #endif /* included_vlib_buffer_funcs_h */
1168 * fd.io coding-style-patch-verification: ON
1171 * eval: (c-set-style "gnu")