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>
45 #include <vlib/buffer.h>
46 #include <vlib/physmem_funcs.h>
47 #include <vlib/main.h>
48 #include <vlib/node.h>
51 vlib buffer access methods.
55 vlib_buffer_validate (vlib_main_t * vm, vlib_buffer_t * b)
57 vlib_buffer_main_t *bm = vm->buffer_main;
58 vlib_buffer_pool_t *bp;
60 /* reference count in allocated buffer always must be 1 or higher */
61 ASSERT (b->ref_count > 0);
63 /* verify that buffer pool index is valid */
64 bp = vec_elt_at_index (bm->buffer_pools, b->buffer_pool_index);
65 ASSERT (pointer_to_uword (b) >= bp->start);
66 ASSERT (pointer_to_uword (b) < bp->start + bp->size -
67 (bp->data_size + sizeof (vlib_buffer_t)));
71 vlib_buffer_ptr_from_index (uword buffer_mem_start, u32 buffer_index,
74 offset += ((uword) buffer_index) << CLIB_LOG2_CACHE_LINE_BYTES;
75 return uword_to_pointer (buffer_mem_start + offset, vlib_buffer_t *);
78 /** \brief Translate buffer index into buffer pointer
80 @param vm - (vlib_main_t *) vlib main data structure pointer
81 @param buffer_index - (u32) buffer index
82 @return - (vlib_buffer_t *) buffer pointer
84 always_inline vlib_buffer_t *
85 vlib_get_buffer (vlib_main_t * vm, u32 buffer_index)
87 vlib_buffer_main_t *bm = vm->buffer_main;
90 b = vlib_buffer_ptr_from_index (bm->buffer_mem_start, buffer_index, 0);
91 vlib_buffer_validate (vm, b);
95 static_always_inline u32
96 vlib_buffer_get_default_data_size (vlib_main_t * vm)
98 return vm->buffer_main->default_data_size;
101 static_always_inline void
102 vlib_buffer_copy_indices (u32 * dst, u32 * src, u32 n_indices)
104 #if defined(CLIB_HAVE_VEC512)
105 while (n_indices >= 16)
107 u32x16_store_unaligned (u32x16_load_unaligned (src), dst);
114 #if defined(CLIB_HAVE_VEC256)
115 while (n_indices >= 8)
117 u32x8_store_unaligned (u32x8_load_unaligned (src), dst);
124 #if defined(CLIB_HAVE_VEC128)
125 while (n_indices >= 4)
127 u32x4_store_unaligned (u32x4_load_unaligned (src), dst);
144 vlib_buffer_copy_indices_from_ring (u32 * dst, u32 * ring, u32 start,
145 u32 ring_size, u32 n_buffers)
147 ASSERT (n_buffers <= ring_size);
149 if (PREDICT_TRUE (start + n_buffers <= ring_size))
151 vlib_buffer_copy_indices (dst, ring + start, n_buffers);
155 u32 n = ring_size - start;
156 vlib_buffer_copy_indices (dst, ring + start, n);
157 vlib_buffer_copy_indices (dst + n, ring, n_buffers - n);
162 vlib_buffer_copy_indices_to_ring (u32 * ring, u32 * src, u32 start,
163 u32 ring_size, u32 n_buffers)
165 ASSERT (n_buffers <= ring_size);
167 if (PREDICT_TRUE (start + n_buffers <= ring_size))
169 vlib_buffer_copy_indices (ring + start, src, n_buffers);
173 u32 n = ring_size - start;
174 vlib_buffer_copy_indices (ring + start, src, n);
175 vlib_buffer_copy_indices (ring, src + n, n_buffers - n);
179 STATIC_ASSERT_OFFSET_OF (vlib_buffer_t, template_end, 64);
180 static_always_inline void
181 vlib_buffer_copy_template (vlib_buffer_t * b, vlib_buffer_t * bt)
183 #if defined CLIB_HAVE_VEC512
184 b->as_u8x64[0] = bt->as_u8x64[0];
185 #elif defined (CLIB_HAVE_VEC256)
186 b->as_u8x32[0] = bt->as_u8x32[0];
187 b->as_u8x32[1] = bt->as_u8x32[1];
188 #elif defined (CLIB_HAVE_VEC128)
189 b->as_u8x16[0] = bt->as_u8x16[0];
190 b->as_u8x16[1] = bt->as_u8x16[1];
191 b->as_u8x16[2] = bt->as_u8x16[2];
192 b->as_u8x16[3] = bt->as_u8x16[3];
194 clib_memcpy_fast (b, bt, 64);
199 vlib_buffer_pool_get_default_for_numa (vlib_main_t * vm, u32 numa_node)
201 ASSERT (numa_node < VLIB_BUFFER_MAX_NUMA_NODES);
202 return vm->buffer_main->default_buffer_pool_index_for_numa[numa_node];
205 /** \brief Translate array of buffer indices into buffer pointers with offset
207 @param vm - (vlib_main_t *) vlib main data structure pointer
208 @param bi - (u32 *) array of buffer indices
209 @param b - (void **) array to store buffer pointers
210 @param count - (uword) number of elements
211 @param offset - (i32) offset applied to each pointer
213 static_always_inline void
214 vlib_get_buffers_with_offset (vlib_main_t * vm, u32 * bi, void **b, int count,
217 uword buffer_mem_start = vm->buffer_main->buffer_mem_start;
218 #ifdef CLIB_HAVE_VEC256
219 u64x4 off = u64x4_splat (buffer_mem_start + offset);
220 /* if count is not const, compiler will not unroll while loop
221 se we maintain two-in-parallel variant */
224 u64x4 b0 = u64x4_from_u32x4 (u32x4_load_unaligned (bi));
225 u64x4 b1 = u64x4_from_u32x4 (u32x4_load_unaligned (bi + 4));
226 /* shift and add to get vlib_buffer_t pointer */
227 u64x4_store_unaligned ((b0 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b);
228 u64x4_store_unaligned ((b1 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b + 4);
236 #ifdef CLIB_HAVE_VEC256
237 u64x4 b0 = u64x4_from_u32x4 (u32x4_load_unaligned (bi));
238 /* shift and add to get vlib_buffer_t pointer */
239 u64x4_store_unaligned ((b0 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b);
240 #elif defined (CLIB_HAVE_VEC128)
241 u64x2 off = u64x2_splat (buffer_mem_start + offset);
242 u32x4 bi4 = u32x4_load_unaligned (bi);
243 u64x2 b0 = u64x2_from_u32x4 ((u32x4) bi4);
244 #if defined (__aarch64__)
245 u64x2 b1 = u64x2_from_u32x4_high ((u32x4) bi4);
247 bi4 = u32x4_shuffle (bi4, 2, 3, 0, 1);
248 u64x2 b1 = u64x2_from_u32x4 ((u32x4) bi4);
250 u64x2_store_unaligned ((b0 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b);
251 u64x2_store_unaligned ((b1 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b + 2);
253 b[0] = vlib_buffer_ptr_from_index (buffer_mem_start, bi[0], offset);
254 b[1] = vlib_buffer_ptr_from_index (buffer_mem_start, bi[1], offset);
255 b[2] = vlib_buffer_ptr_from_index (buffer_mem_start, bi[2], offset);
256 b[3] = vlib_buffer_ptr_from_index (buffer_mem_start, bi[3], offset);
264 b[0] = vlib_buffer_ptr_from_index (buffer_mem_start, bi[0], offset);
271 /** \brief Translate array of buffer indices into buffer pointers
273 @param vm - (vlib_main_t *) vlib main data structure pointer
274 @param bi - (u32 *) array of buffer indices
275 @param b - (vlib_buffer_t **) array to store buffer pointers
276 @param count - (uword) number of elements
279 static_always_inline void
280 vlib_get_buffers (vlib_main_t * vm, u32 * bi, vlib_buffer_t ** b, int count)
282 vlib_get_buffers_with_offset (vm, bi, (void **) b, count, 0);
285 /** \brief Translate buffer pointer into buffer index
287 @param vm - (vlib_main_t *) vlib main data structure pointer
288 @param p - (void *) buffer pointer
289 @return - (u32) buffer index
293 vlib_get_buffer_index (vlib_main_t * vm, void *p)
295 vlib_buffer_main_t *bm = vm->buffer_main;
296 uword offset = pointer_to_uword (p) - bm->buffer_mem_start;
297 ASSERT (pointer_to_uword (p) >= bm->buffer_mem_start);
298 ASSERT (offset < bm->buffer_mem_size);
299 ASSERT ((offset % (1 << CLIB_LOG2_CACHE_LINE_BYTES)) == 0);
300 return offset >> CLIB_LOG2_CACHE_LINE_BYTES;
303 /** \brief Translate array of buffer pointers into buffer indices with offset
305 @param vm - (vlib_main_t *) vlib main data structure pointer
306 @param b - (void **) array of buffer pointers
307 @param bi - (u32 *) array to store buffer indices
308 @param count - (uword) number of elements
309 @param offset - (i32) offset applied to each pointer
311 static_always_inline void
312 vlib_get_buffer_indices_with_offset (vlib_main_t * vm, void **b, u32 * bi,
313 uword count, i32 offset)
315 #ifdef CLIB_HAVE_VEC256
316 u32x8 mask = { 0, 2, 4, 6, 1, 3, 5, 7 };
317 u64x4 off4 = u64x4_splat (vm->buffer_main->buffer_mem_start - offset);
321 /* load 4 pointers into 256-bit register */
322 u64x4 v0 = u64x4_load_unaligned (b);
323 u64x4 v1 = u64x4_load_unaligned (b + 4);
329 v0 >>= CLIB_LOG2_CACHE_LINE_BYTES;
330 v1 >>= CLIB_LOG2_CACHE_LINE_BYTES;
332 /* permute 256-bit register so lower u32s of each buffer index are
333 * placed into lower 128-bits */
334 v2 = u32x8_permute ((u32x8) v0, mask);
335 v3 = u32x8_permute ((u32x8) v1, mask);
337 /* extract lower 128-bits and save them to the array of buffer indices */
338 u32x4_store_unaligned (u32x8_extract_lo (v2), bi);
339 u32x4_store_unaligned (u32x8_extract_lo (v3), bi + 4);
347 /* equivalent non-nector implementation */
348 bi[0] = vlib_get_buffer_index (vm, ((u8 *) b[0]) + offset);
349 bi[1] = vlib_get_buffer_index (vm, ((u8 *) b[1]) + offset);
350 bi[2] = vlib_get_buffer_index (vm, ((u8 *) b[2]) + offset);
351 bi[3] = vlib_get_buffer_index (vm, ((u8 *) b[3]) + offset);
358 bi[0] = vlib_get_buffer_index (vm, ((u8 *) b[0]) + offset);
365 /** \brief Translate array of buffer pointers into buffer indices
367 @param vm - (vlib_main_t *) vlib main data structure pointer
368 @param b - (vlib_buffer_t **) array of buffer pointers
369 @param bi - (u32 *) array to store buffer indices
370 @param count - (uword) number of elements
372 static_always_inline void
373 vlib_get_buffer_indices (vlib_main_t * vm, vlib_buffer_t ** b, u32 * bi,
376 vlib_get_buffer_indices_with_offset (vm, (void **) b, bi, count, 0);
379 /** \brief Get next buffer in buffer linklist, or zero for end of list.
381 @param vm - (vlib_main_t *) vlib main data structure pointer
382 @param b - (void *) buffer pointer
383 @return - (vlib_buffer_t *) next buffer, or NULL
385 always_inline vlib_buffer_t *
386 vlib_get_next_buffer (vlib_main_t * vm, vlib_buffer_t * b)
388 return (b->flags & VLIB_BUFFER_NEXT_PRESENT
389 ? vlib_get_buffer (vm, b->next_buffer) : 0);
392 uword vlib_buffer_length_in_chain_slow_path (vlib_main_t * vm,
393 vlib_buffer_t * b_first);
395 /** \brief Get length in bytes of the buffer chain
397 @param vm - (vlib_main_t *) vlib main data structure pointer
398 @param b - (void *) buffer pointer
399 @return - (uword) length of buffer chain
402 vlib_buffer_length_in_chain (vlib_main_t * vm, vlib_buffer_t * b)
404 uword len = b->current_length;
406 if (PREDICT_TRUE ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0))
409 if (PREDICT_TRUE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID))
410 return len + b->total_length_not_including_first_buffer;
412 return vlib_buffer_length_in_chain_slow_path (vm, b);
415 /** \brief Get length in bytes of the buffer index buffer chain
417 @param vm - (vlib_main_t *) vlib main data structure pointer
418 @param bi - (u32) buffer index
419 @return - (uword) length of buffer chain
422 vlib_buffer_index_length_in_chain (vlib_main_t * vm, u32 bi)
424 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
425 return vlib_buffer_length_in_chain (vm, b);
428 /** \brief Copy buffer contents to memory
430 @param vm - (vlib_main_t *) vlib main data structure pointer
431 @param buffer_index - (u32) buffer index
432 @param contents - (u8 *) memory, <strong>must be large enough</strong>
433 @return - (uword) length of buffer chain
436 vlib_buffer_contents (vlib_main_t * vm, u32 buffer_index, u8 * contents)
438 uword content_len = 0;
444 b = vlib_get_buffer (vm, buffer_index);
445 l = b->current_length;
446 clib_memcpy_fast (contents + content_len, b->data + b->current_data, l);
448 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
450 buffer_index = b->next_buffer;
457 vlib_buffer_get_pa (vlib_main_t * vm, vlib_buffer_t * b)
459 return vlib_physmem_get_pa (vm, b->data);
463 vlib_buffer_get_current_pa (vlib_main_t * vm, vlib_buffer_t * b)
465 return vlib_buffer_get_pa (vm, b) + b->current_data;
468 /** \brief Prefetch buffer metadata by buffer index
469 The first 64 bytes of buffer contains most header information
471 @param vm - (vlib_main_t *) vlib main data structure pointer
472 @param bi - (u32) buffer index
473 @param type - LOAD, STORE. In most cases, STORE is the right answer
475 /* Prefetch buffer header given index. */
476 #define vlib_prefetch_buffer_with_index(vm,bi,type) \
478 vlib_buffer_t * _b = vlib_get_buffer (vm, bi); \
479 vlib_prefetch_buffer_header (_b, type); \
484 /* Index is unknown. */
487 /* Index is known and free/allocated. */
488 VLIB_BUFFER_KNOWN_FREE,
489 VLIB_BUFFER_KNOWN_ALLOCATED,
490 } vlib_buffer_known_state_t;
492 void vlib_buffer_validate_alloc_free (vlib_main_t * vm, u32 * buffers,
494 vlib_buffer_known_state_t
497 always_inline vlib_buffer_known_state_t
498 vlib_buffer_is_known (vlib_main_t * vm, u32 buffer_index)
500 vlib_buffer_main_t *bm = vm->buffer_main;
502 clib_spinlock_lock (&bm->buffer_known_hash_lockp);
503 uword *p = hash_get (bm->buffer_known_hash, buffer_index);
504 clib_spinlock_unlock (&bm->buffer_known_hash_lockp);
505 return p ? p[0] : VLIB_BUFFER_UNKNOWN;
508 /* Validates sanity of a single buffer.
509 Returns format'ed vector with error message if any. */
510 u8 *vlib_validate_buffer (vlib_main_t * vm, u32 buffer_index,
513 u8 *vlib_validate_buffers (vlib_main_t * vm,
515 uword next_buffer_stride,
517 vlib_buffer_known_state_t known_state,
518 uword follow_buffer_next);
520 static_always_inline vlib_buffer_pool_t *
521 vlib_get_buffer_pool (vlib_main_t * vm, u8 buffer_pool_index)
523 vlib_buffer_main_t *bm = vm->buffer_main;
524 return vec_elt_at_index (bm->buffer_pools, buffer_pool_index);
527 static_always_inline __clib_warn_unused_result uword
528 vlib_buffer_pool_get (vlib_main_t * vm, u8 buffer_pool_index, u32 * buffers,
531 vlib_buffer_pool_t *bp = vlib_get_buffer_pool (vm, buffer_pool_index);
534 ASSERT (bp->buffers);
536 clib_spinlock_lock (&bp->lock);
538 if (PREDICT_TRUE (n_buffers < len))
541 vlib_buffer_copy_indices (buffers, bp->buffers + len, n_buffers);
543 clib_spinlock_unlock (&bp->lock);
548 vlib_buffer_copy_indices (buffers, bp->buffers, len);
550 clib_spinlock_unlock (&bp->lock);
556 /** \brief Allocate buffers from specific pool into supplied array
558 @param vm - (vlib_main_t *) vlib main data structure pointer
559 @param buffers - (u32 * ) buffer index array
560 @param n_buffers - (u32) number of buffers requested
561 @return - (u32) number of buffers actually allocated, may be
562 less than the number requested or zero
565 always_inline __clib_warn_unused_result u32
566 vlib_buffer_alloc_from_pool (vlib_main_t * vm, u32 * buffers, u32 n_buffers,
567 u8 buffer_pool_index)
569 vlib_buffer_main_t *bm = vm->buffer_main;
570 vlib_buffer_pool_t *bp;
571 vlib_buffer_pool_thread_t *bpt;
572 u32 *src, *dst, len, n_left;
574 /* If buffer allocation fault injection is configured */
575 if (VLIB_BUFFER_ALLOC_FAULT_INJECTOR > 0)
577 u32 vlib_buffer_alloc_may_fail (vlib_main_t *, u32);
579 /* See how many buffers we're willing to allocate */
580 n_buffers = vlib_buffer_alloc_may_fail (vm, n_buffers);
585 bp = vec_elt_at_index (bm->buffer_pools, buffer_pool_index);
586 bpt = vec_elt_at_index (bp->threads, vm->thread_index);
592 /* per-thread cache contains enough buffers */
593 if (len >= n_buffers)
595 src = bpt->cached_buffers + len - n_buffers;
596 vlib_buffer_copy_indices (dst, src, n_buffers);
597 bpt->n_cached -= n_buffers;
600 vlib_buffer_validate_alloc_free (vm, buffers, n_buffers,
601 VLIB_BUFFER_KNOWN_FREE);
605 /* alloc bigger than cache - take buffers directly from main pool */
606 if (n_buffers >= VLIB_BUFFER_POOL_PER_THREAD_CACHE_SZ)
608 n_buffers = vlib_buffer_pool_get (vm, buffer_pool_index, buffers,
612 vlib_buffer_validate_alloc_free (vm, buffers, n_buffers,
613 VLIB_BUFFER_KNOWN_FREE);
617 /* take everything available in the cache */
620 vlib_buffer_copy_indices (dst, bpt->cached_buffers, len);
626 len = round_pow2 (n_left, 32);
627 len = vlib_buffer_pool_get (vm, buffer_pool_index, bpt->cached_buffers,
633 u32 n_copy = clib_min (len, n_left);
634 src = bpt->cached_buffers + len - n_copy;
635 vlib_buffer_copy_indices (dst, src, n_copy);
636 bpt->n_cached -= n_copy;
642 /* Verify that buffers are known free. */
644 vlib_buffer_validate_alloc_free (vm, buffers, n_buffers,
645 VLIB_BUFFER_KNOWN_FREE);
650 /** \brief Allocate buffers from specific numa node into supplied array
652 @param vm - (vlib_main_t *) vlib main data structure pointer
653 @param buffers - (u32 * ) buffer index array
654 @param n_buffers - (u32) number of buffers requested
655 @param numa_node - (u32) numa node
656 @return - (u32) number of buffers actually allocated, may be
657 less than the number requested or zero
659 always_inline __clib_warn_unused_result u32
660 vlib_buffer_alloc_on_numa (vlib_main_t * vm, u32 * buffers, u32 n_buffers,
663 u8 index = vlib_buffer_pool_get_default_for_numa (vm, numa_node);
664 return vlib_buffer_alloc_from_pool (vm, buffers, n_buffers, index);
667 /** \brief Allocate buffers into supplied array
669 @param vm - (vlib_main_t *) vlib main data structure pointer
670 @param buffers - (u32 * ) buffer index array
671 @param n_buffers - (u32) number of buffers requested
672 @return - (u32) number of buffers actually allocated, may be
673 less than the number requested or zero
676 always_inline __clib_warn_unused_result u32
677 vlib_buffer_alloc (vlib_main_t * vm, u32 * buffers, u32 n_buffers)
679 return vlib_buffer_alloc_on_numa (vm, buffers, n_buffers, vm->numa_node);
682 /** \brief Allocate buffers into ring
684 @param vm - (vlib_main_t *) vlib main data structure pointer
685 @param buffers - (u32 * ) buffer index ring
686 @param start - (u32) first slot in the ring
687 @param ring_size - (u32) ring size
688 @param n_buffers - (u32) number of buffers requested
689 @return - (u32) number of buffers actually allocated, may be
690 less than the number requested or zero
692 always_inline __clib_warn_unused_result u32
693 vlib_buffer_alloc_to_ring (vlib_main_t * vm, u32 * ring, u32 start,
694 u32 ring_size, u32 n_buffers)
698 ASSERT (n_buffers <= ring_size);
700 if (PREDICT_TRUE (start + n_buffers <= ring_size))
701 return vlib_buffer_alloc (vm, ring + start, n_buffers);
703 n_alloc = vlib_buffer_alloc (vm, ring + start, ring_size - start);
705 if (PREDICT_TRUE (n_alloc == ring_size - start))
706 n_alloc += vlib_buffer_alloc (vm, ring, n_buffers - n_alloc);
711 /** \brief Allocate buffers into ring from specific buffer pool
713 @param vm - (vlib_main_t *) vlib main data structure pointer
714 @param buffers - (u32 * ) buffer index ring
715 @param start - (u32) first slot in the ring
716 @param ring_size - (u32) ring size
717 @param n_buffers - (u32) number of buffers requested
718 @return - (u32) number of buffers actually allocated, may be
719 less than the number requested or zero
721 always_inline __clib_warn_unused_result u32
722 vlib_buffer_alloc_to_ring_from_pool (vlib_main_t * vm, u32 * ring, u32 start,
723 u32 ring_size, u32 n_buffers,
724 u8 buffer_pool_index)
728 ASSERT (n_buffers <= ring_size);
730 if (PREDICT_TRUE (start + n_buffers <= ring_size))
731 return vlib_buffer_alloc_from_pool (vm, ring + start, n_buffers,
734 n_alloc = vlib_buffer_alloc_from_pool (vm, ring + start, ring_size - start,
737 if (PREDICT_TRUE (n_alloc == ring_size - start))
738 n_alloc += vlib_buffer_alloc_from_pool (vm, ring, n_buffers - n_alloc,
744 static_always_inline void
745 vlib_buffer_pool_put (vlib_main_t * vm, u8 buffer_pool_index,
746 u32 * buffers, u32 n_buffers)
748 vlib_buffer_pool_t *bp = vlib_get_buffer_pool (vm, buffer_pool_index);
749 vlib_buffer_pool_thread_t *bpt = vec_elt_at_index (bp->threads,
751 u32 n_cached, n_empty;
754 vlib_buffer_validate_alloc_free (vm, buffers, n_buffers,
755 VLIB_BUFFER_KNOWN_ALLOCATED);
757 n_cached = bpt->n_cached;
758 n_empty = VLIB_BUFFER_POOL_PER_THREAD_CACHE_SZ - n_cached;
759 if (n_buffers <= n_empty)
761 vlib_buffer_copy_indices (bpt->cached_buffers + n_cached,
763 bpt->n_cached = n_cached + n_buffers;
767 vlib_buffer_copy_indices (bpt->cached_buffers + n_cached,
768 buffers + n_buffers - n_empty, n_empty);
769 bpt->n_cached = VLIB_BUFFER_POOL_PER_THREAD_CACHE_SZ;
771 clib_spinlock_lock (&bp->lock);
772 vlib_buffer_copy_indices (bp->buffers + bp->n_avail, buffers,
773 n_buffers - n_empty);
774 bp->n_avail += n_buffers - n_empty;
775 clib_spinlock_unlock (&bp->lock);
778 static_always_inline void
779 vlib_buffer_free_inline (vlib_main_t * vm, u32 * buffers, u32 n_buffers,
782 const int queue_size = 128;
783 vlib_buffer_pool_t *bp = 0;
784 u8 buffer_pool_index = ~0;
785 u32 n_queue = 0, queue[queue_size + 4];
786 vlib_buffer_t bt = { };
787 #if defined(CLIB_HAVE_VEC128)
788 vlib_buffer_t bpi_mask = {.buffer_pool_index = ~0 };
789 vlib_buffer_t bpi_vec = {};
790 vlib_buffer_t flags_refs_mask = {
791 .flags = VLIB_BUFFER_NEXT_PRESENT,
796 if (PREDICT_FALSE (n_buffers == 0))
799 vlib_buffer_t *b = vlib_get_buffer (vm, buffers[0]);
800 buffer_pool_index = b->buffer_pool_index;
801 bp = vlib_get_buffer_pool (vm, buffer_pool_index);
802 vlib_buffer_copy_template (&bt, &bp->buffer_template);
803 #if defined(CLIB_HAVE_VEC128)
804 bpi_vec.buffer_pool_index = buffer_pool_index;
810 u32 bi, sum = 0, flags, next;
815 vlib_get_buffers (vm, buffers, b, 4);
819 vlib_get_buffers (vm, buffers + 8, b + 4, 4);
820 vlib_prefetch_buffer_header (b[4], LOAD);
821 vlib_prefetch_buffer_header (b[5], LOAD);
822 vlib_prefetch_buffer_header (b[6], LOAD);
823 vlib_prefetch_buffer_header (b[7], LOAD);
826 #if defined(CLIB_HAVE_VEC128)
827 u8x16 p0, p1, p2, p3, r;
828 p0 = u8x16_load_unaligned (b[0]);
829 p1 = u8x16_load_unaligned (b[1]);
830 p2 = u8x16_load_unaligned (b[2]);
831 p3 = u8x16_load_unaligned (b[3]);
833 r = p0 ^ bpi_vec.as_u8x16[0];
834 r |= p1 ^ bpi_vec.as_u8x16[0];
835 r |= p2 ^ bpi_vec.as_u8x16[0];
836 r |= p3 ^ bpi_vec.as_u8x16[0];
837 r &= bpi_mask.as_u8x16[0];
838 r |= (p0 | p1 | p2 | p3) & flags_refs_mask.as_u8x16[0];
840 sum = !u8x16_is_all_zero (r);
846 sum &= VLIB_BUFFER_NEXT_PRESENT;
847 sum += b[0]->ref_count - 1;
848 sum += b[1]->ref_count - 1;
849 sum += b[2]->ref_count - 1;
850 sum += b[3]->ref_count - 1;
851 sum |= b[0]->buffer_pool_index ^ buffer_pool_index;
852 sum |= b[1]->buffer_pool_index ^ buffer_pool_index;
853 sum |= b[2]->buffer_pool_index ^ buffer_pool_index;
854 sum |= b[3]->buffer_pool_index ^ buffer_pool_index;
860 vlib_buffer_copy_indices (queue + n_queue, buffers, 4);
861 vlib_buffer_copy_template (b[0], &bt);
862 vlib_buffer_copy_template (b[1], &bt);
863 vlib_buffer_copy_template (b[2], &bt);
864 vlib_buffer_copy_template (b[3], &bt);
867 vlib_buffer_validate (vm, b[0]);
868 vlib_buffer_validate (vm, b[1]);
869 vlib_buffer_validate (vm, b[2]);
870 vlib_buffer_validate (vm, b[3]);
872 VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b[0]);
873 VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b[1]);
874 VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b[2]);
875 VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b[3]);
877 if (n_queue >= queue_size)
879 vlib_buffer_pool_put (vm, buffer_pool_index, queue, n_queue);
890 b[0] = vlib_get_buffer (vm, bi);
892 next = b[0]->next_buffer;
894 if (PREDICT_FALSE (buffer_pool_index != b[0]->buffer_pool_index))
899 vlib_buffer_pool_put (vm, buffer_pool_index, queue, n_queue);
903 buffer_pool_index = b[0]->buffer_pool_index;
904 #if defined(CLIB_HAVE_VEC128)
905 bpi_vec.buffer_pool_index = buffer_pool_index;
907 bp = vlib_get_buffer_pool (vm, buffer_pool_index);
908 vlib_buffer_copy_template (&bt, &bp->buffer_template);
911 vlib_buffer_validate (vm, b[0]);
913 VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b[0]);
915 if (clib_atomic_sub_fetch (&b[0]->ref_count, 1) == 0)
917 vlib_buffer_copy_template (b[0], &bt);
918 queue[n_queue++] = bi;
921 if (n_queue == queue_size)
923 vlib_buffer_pool_put (vm, buffer_pool_index, queue, queue_size);
927 if (maybe_next && (flags & VLIB_BUFFER_NEXT_PRESENT))
938 vlib_buffer_pool_put (vm, buffer_pool_index, queue, n_queue);
942 /** \brief Free buffers
943 Frees the entire buffer chain for each buffer
945 @param vm - (vlib_main_t *) vlib main data structure pointer
946 @param buffers - (u32 * ) buffer index array
947 @param n_buffers - (u32) number of buffers to free
951 vlib_buffer_free (vlib_main_t * vm,
952 /* pointer to first buffer */
954 /* number of buffers to free */
957 vlib_buffer_free_inline (vm, buffers, n_buffers, /* maybe next */ 1);
960 /** \brief Free buffers, does not free the buffer chain for each buffer
962 @param vm - (vlib_main_t *) vlib main data structure pointer
963 @param buffers - (u32 * ) buffer index array
964 @param n_buffers - (u32) number of buffers to free
968 vlib_buffer_free_no_next (vlib_main_t * vm,
969 /* pointer to first buffer */
971 /* number of buffers to free */
974 vlib_buffer_free_inline (vm, buffers, n_buffers, /* maybe next */ 0);
977 /** \brief Free one buffer
978 Shorthand to free a single buffer chain.
980 @param vm - (vlib_main_t *) vlib main data structure pointer
981 @param buffer_index - (u32) buffer index to free
984 vlib_buffer_free_one (vlib_main_t * vm, u32 buffer_index)
986 vlib_buffer_free_inline (vm, &buffer_index, 1, /* maybe next */ 1);
989 /** \brief Free buffers from ring
991 @param vm - (vlib_main_t *) vlib main data structure pointer
992 @param buffers - (u32 * ) buffer index ring
993 @param start - (u32) first slot in the ring
994 @param ring_size - (u32) ring size
995 @param n_buffers - (u32) number of buffers
998 vlib_buffer_free_from_ring (vlib_main_t * vm, u32 * ring, u32 start,
999 u32 ring_size, u32 n_buffers)
1001 ASSERT (n_buffers <= ring_size);
1003 if (PREDICT_TRUE (start + n_buffers <= ring_size))
1005 vlib_buffer_free (vm, ring + start, n_buffers);
1009 vlib_buffer_free (vm, ring + start, ring_size - start);
1010 vlib_buffer_free (vm, ring, n_buffers - (ring_size - start));
1014 /** \brief Free buffers from ring without freeing tail buffers
1016 @param vm - (vlib_main_t *) vlib main data structure pointer
1017 @param buffers - (u32 * ) buffer index ring
1018 @param start - (u32) first slot in the ring
1019 @param ring_size - (u32) ring size
1020 @param n_buffers - (u32) number of buffers
1023 vlib_buffer_free_from_ring_no_next (vlib_main_t * vm, u32 * ring, u32 start,
1024 u32 ring_size, u32 n_buffers)
1026 ASSERT (n_buffers <= ring_size);
1028 if (PREDICT_TRUE (start + n_buffers <= ring_size))
1030 vlib_buffer_free_no_next (vm, ring + start, n_buffers);
1034 vlib_buffer_free_no_next (vm, ring + start, ring_size - start);
1035 vlib_buffer_free_no_next (vm, ring, n_buffers - (ring_size - start));
1039 /* Append given data to end of buffer, possibly allocating new buffers. */
1040 int vlib_buffer_add_data (vlib_main_t * vm, u32 * buffer_index, void *data,
1043 /* Define vlib_buffer and vnet_buffer flags bits preserved for copy/clone */
1044 #define VLIB_BUFFER_COPY_CLONE_FLAGS_MASK \
1045 (VLIB_BUFFER_NEXT_PRESENT | VLIB_BUFFER_TOTAL_LENGTH_VALID | \
1046 VLIB_BUFFER_IS_TRACED | ~VLIB_BUFFER_FLAGS_ALL)
1048 /* duplicate all buffers in chain */
1049 always_inline vlib_buffer_t *
1050 vlib_buffer_copy (vlib_main_t * vm, vlib_buffer_t * b)
1052 vlib_buffer_t *s, *d, *fd;
1053 uword n_alloc, n_buffers = 1;
1054 u32 flag_mask = VLIB_BUFFER_COPY_CLONE_FLAGS_MASK;
1058 while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
1061 s = vlib_get_buffer (vm, s->next_buffer);
1063 u32 new_buffers[n_buffers];
1065 n_alloc = vlib_buffer_alloc (vm, new_buffers, n_buffers);
1067 /* No guarantee that we'll get all the buffers we asked for */
1068 if (PREDICT_FALSE (n_alloc < n_buffers))
1071 vlib_buffer_free (vm, new_buffers, n_alloc);
1077 fd = d = vlib_get_buffer (vm, new_buffers[0]);
1078 d->current_data = s->current_data;
1079 d->current_length = s->current_length;
1080 d->flags = s->flags & flag_mask;
1081 d->trace_handle = s->trace_handle;
1082 d->total_length_not_including_first_buffer =
1083 s->total_length_not_including_first_buffer;
1084 clib_memcpy_fast (d->opaque, s->opaque, sizeof (s->opaque));
1085 clib_memcpy_fast (d->opaque2, s->opaque2, sizeof (s->opaque2));
1086 clib_memcpy_fast (vlib_buffer_get_current (d),
1087 vlib_buffer_get_current (s), s->current_length);
1090 for (i = 1; i < n_buffers; i++)
1093 d->next_buffer = new_buffers[i];
1095 s = vlib_get_buffer (vm, s->next_buffer);
1096 d = vlib_get_buffer (vm, new_buffers[i]);
1097 d->current_data = s->current_data;
1098 d->current_length = s->current_length;
1099 clib_memcpy_fast (vlib_buffer_get_current (d),
1100 vlib_buffer_get_current (s), s->current_length);
1101 d->flags = s->flags & flag_mask;
1107 /* duplicate first buffer in chain */
1108 always_inline vlib_buffer_t *
1109 vlib_buffer_copy_no_chain (vlib_main_t * vm, vlib_buffer_t * b, u32 * di)
1113 if ((vlib_buffer_alloc (vm, di, 1)) != 1)
1116 d = vlib_get_buffer (vm, *di);
1118 d->current_data = b->current_data;
1119 d->current_length = b->current_length;
1120 clib_memcpy_fast (d->opaque, b->opaque, sizeof (b->opaque));
1121 clib_memcpy_fast (d->opaque2, b->opaque2, sizeof (b->opaque2));
1122 clib_memcpy_fast (vlib_buffer_get_current (d),
1123 vlib_buffer_get_current (b), b->current_length);
1128 /* \brief Move packet from current position to offset position in buffer.
1129 Only work for small packet using one buffer with room to fit the move
1130 @param vm - (vlib_main_t *) vlib main data structure pointer
1131 @param b - (vlib_buffer_t *) pointer to buffer
1132 @param offset - (i16) position to move the packet in buffer
1135 vlib_buffer_move (vlib_main_t * vm, vlib_buffer_t * b, i16 offset)
1137 ASSERT ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
1138 ASSERT (offset + VLIB_BUFFER_PRE_DATA_SIZE >= 0);
1139 ASSERT (offset + b->current_length <
1140 vlib_buffer_get_default_data_size (vm));
1142 u8 *source = vlib_buffer_get_current (b);
1143 b->current_data = offset;
1144 u8 *destination = vlib_buffer_get_current (b);
1145 u16 length = b->current_length;
1147 if (source + length <= destination) /* no overlap */
1148 clib_memcpy_fast (destination, source, length);
1150 memmove (destination, source, length);
1153 /** \brief Create a maximum of 256 clones of buffer and store them
1154 in the supplied array
1156 @param vm - (vlib_main_t *) vlib main data structure pointer
1157 @param src_buffer - (u32) source buffer index
1158 @param buffers - (u32 * ) buffer index array
1159 @param n_buffers - (u16) number of buffer clones requested (<=256)
1160 @param head_end_offset - (u16) offset relative to current position
1161 where packet head ends
1162 @param offset - (i16) copy packet head at current position if 0,
1163 else at offset position to change headroom space as specified
1164 @return - (u16) number of buffers actually cloned, may be
1165 less than the number requested or zero
1168 vlib_buffer_clone_256 (vlib_main_t * vm, u32 src_buffer, u32 * buffers,
1169 u16 n_buffers, u16 head_end_offset, i16 offset)
1172 vlib_buffer_t *s = vlib_get_buffer (vm, src_buffer);
1174 ASSERT (s->ref_count == 1);
1176 ASSERT (n_buffers <= 256);
1177 ASSERT (offset + VLIB_BUFFER_PRE_DATA_SIZE >= 0);
1178 ASSERT ((offset + head_end_offset) <
1179 vlib_buffer_get_default_data_size (vm));
1181 if (s->current_length <= head_end_offset + CLIB_CACHE_LINE_BYTES * 2)
1183 buffers[0] = src_buffer;
1185 vlib_buffer_move (vm, s, offset);
1187 for (i = 1; i < n_buffers; i++)
1190 d = vlib_buffer_copy (vm, s);
1193 buffers[i] = vlib_get_buffer_index (vm, d);
1199 if (PREDICT_FALSE ((n_buffers == 1) && (offset == 0)))
1201 buffers[0] = src_buffer;
1205 n_buffers = vlib_buffer_alloc_from_pool (vm, buffers, n_buffers,
1206 s->buffer_pool_index);
1208 for (i = 0; i < n_buffers; i++)
1210 vlib_buffer_t *d = vlib_get_buffer (vm, buffers[i]);
1212 d->current_data = offset;
1214 d->current_data = s->current_data;
1216 d->current_length = head_end_offset;
1217 ASSERT (d->buffer_pool_index == s->buffer_pool_index);
1219 d->total_length_not_including_first_buffer = s->current_length -
1221 if (PREDICT_FALSE (s->flags & VLIB_BUFFER_NEXT_PRESENT))
1223 d->total_length_not_including_first_buffer +=
1224 s->total_length_not_including_first_buffer;
1226 d->flags = (s->flags & VLIB_BUFFER_COPY_CLONE_FLAGS_MASK) |
1227 VLIB_BUFFER_NEXT_PRESENT;
1228 d->trace_handle = s->trace_handle;
1229 clib_memcpy_fast (d->opaque, s->opaque, sizeof (s->opaque));
1230 clib_memcpy_fast (d->opaque2, s->opaque2, sizeof (s->opaque2));
1231 clib_memcpy_fast (vlib_buffer_get_current (d),
1232 vlib_buffer_get_current (s), head_end_offset);
1233 d->next_buffer = src_buffer;
1235 vlib_buffer_advance (s, head_end_offset);
1236 s->ref_count = n_buffers ? n_buffers : s->ref_count;
1237 while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
1239 s = vlib_get_buffer (vm, s->next_buffer);
1240 s->ref_count = n_buffers ? n_buffers : s->ref_count;
1246 /** \brief Create multiple clones of buffer and store them
1247 in the supplied array
1249 @param vm - (vlib_main_t *) vlib main data structure pointer
1250 @param src_buffer - (u32) source buffer index
1251 @param buffers - (u32 * ) buffer index array
1252 @param n_buffers - (u16) number of buffer clones requested (<=256)
1253 @param head_end_offset - (u16) offset relative to current position
1254 where packet head ends
1255 @param offset - (i16) copy packet head at current position if 0,
1256 else at offset position to change headroom space as specified
1257 @return - (u16) number of buffers actually cloned, may be
1258 less than the number requested or zero
1261 vlib_buffer_clone_at_offset (vlib_main_t * vm, u32 src_buffer, u32 * buffers,
1262 u16 n_buffers, u16 head_end_offset, i16 offset)
1264 vlib_buffer_t *s = vlib_get_buffer (vm, src_buffer);
1267 while (n_buffers > 256)
1269 vlib_buffer_t *copy;
1270 copy = vlib_buffer_copy (vm, s);
1271 n_cloned += vlib_buffer_clone_256 (vm,
1272 vlib_get_buffer_index (vm, copy),
1273 (buffers + n_cloned),
1274 256, head_end_offset, offset);
1277 n_cloned += vlib_buffer_clone_256 (vm, src_buffer,
1279 n_buffers, head_end_offset, offset);
1284 /** \brief Create multiple clones of buffer and store them
1285 in the supplied array
1287 @param vm - (vlib_main_t *) vlib main data structure pointer
1288 @param src_buffer - (u32) source buffer index
1289 @param buffers - (u32 * ) buffer index array
1290 @param n_buffers - (u16) number of buffer clones requested (<=256)
1291 @param head_end_offset - (u16) offset relative to current position
1292 where packet head ends
1293 @return - (u16) number of buffers actually cloned, may be
1294 less than the number requested or zero
1297 vlib_buffer_clone (vlib_main_t * vm, u32 src_buffer, u32 * buffers,
1298 u16 n_buffers, u16 head_end_offset)
1300 return vlib_buffer_clone_at_offset (vm, src_buffer, buffers, n_buffers,
1301 head_end_offset, 0);
1304 /** \brief Attach cloned tail to the buffer
1306 @param vm - (vlib_main_t *) vlib main data structure pointer
1307 @param head - (vlib_buffer_t *) head buffer
1308 @param tail - (Vlib buffer_t *) tail buffer to clone and attach to head
1312 vlib_buffer_attach_clone (vlib_main_t * vm, vlib_buffer_t * head,
1313 vlib_buffer_t * tail)
1315 ASSERT ((head->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
1316 ASSERT (head->buffer_pool_index == tail->buffer_pool_index);
1318 head->flags |= VLIB_BUFFER_NEXT_PRESENT;
1319 head->flags &= ~VLIB_BUFFER_TOTAL_LENGTH_VALID;
1320 head->flags &= ~VLIB_BUFFER_EXT_HDR_VALID;
1321 head->flags |= (tail->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID);
1322 head->next_buffer = vlib_get_buffer_index (vm, tail);
1323 head->total_length_not_including_first_buffer = tail->current_length +
1324 tail->total_length_not_including_first_buffer;
1327 clib_atomic_add_fetch (&tail->ref_count, 1);
1329 if (tail->flags & VLIB_BUFFER_NEXT_PRESENT)
1331 tail = vlib_get_buffer (vm, tail->next_buffer);
1336 /* Initializes the buffer as an empty packet with no chained buffers. */
1338 vlib_buffer_chain_init (vlib_buffer_t * first)
1340 first->total_length_not_including_first_buffer = 0;
1341 first->current_length = 0;
1342 first->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
1343 first->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
1346 /* The provided next_bi buffer index is appended to the end of the packet. */
1347 always_inline vlib_buffer_t *
1348 vlib_buffer_chain_buffer (vlib_main_t * vm, vlib_buffer_t * last, u32 next_bi)
1350 vlib_buffer_t *next_buffer = vlib_get_buffer (vm, next_bi);
1351 last->next_buffer = next_bi;
1352 last->flags |= VLIB_BUFFER_NEXT_PRESENT;
1353 next_buffer->current_length = 0;
1354 next_buffer->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
1358 /* Increases or decreases the packet length.
1359 * It does not allocate or deallocate new buffers.
1360 * Therefore, the added length must be compatible
1361 * with the last buffer. */
1363 vlib_buffer_chain_increase_length (vlib_buffer_t * first,
1364 vlib_buffer_t * last, i32 len)
1366 last->current_length += len;
1368 first->total_length_not_including_first_buffer += len;
1371 /* Copy data to the end of the packet and increases its length.
1372 * It does not allocate new buffers.
1373 * Returns the number of copied bytes. */
1375 vlib_buffer_chain_append_data (vlib_main_t * vm,
1376 vlib_buffer_t * first,
1377 vlib_buffer_t * last, void *data, u16 data_len)
1379 u32 n_buffer_bytes = vlib_buffer_get_default_data_size (vm);
1380 ASSERT (n_buffer_bytes >= last->current_length + last->current_data);
1381 u16 len = clib_min (data_len,
1382 n_buffer_bytes - last->current_length -
1383 last->current_data);
1384 clib_memcpy_fast (vlib_buffer_get_current (last) + last->current_length,
1386 vlib_buffer_chain_increase_length (first, last, len);
1390 /* Copy data to the end of the packet and increases its length.
1391 * Allocates additional buffers from the free list if necessary.
1392 * Returns the number of copied bytes.
1393 * 'last' value is modified whenever new buffers are allocated and
1394 * chained and points to the last buffer in the chain. */
1396 vlib_buffer_chain_append_data_with_alloc (vlib_main_t * vm,
1397 vlib_buffer_t * first,
1398 vlib_buffer_t ** last, void *data,
1400 void vlib_buffer_chain_validate (vlib_main_t * vm, vlib_buffer_t * first);
1402 format_function_t format_vlib_buffer, format_vlib_buffer_and_data,
1403 format_vlib_buffer_contents, format_vlib_buffer_no_chain;
1407 /* Vector of packet data. */
1410 /* Number of buffers to allocate in each call to allocator. */
1411 u32 min_n_buffers_each_alloc;
1414 } vlib_packet_template_t;
1416 void vlib_packet_template_init (vlib_main_t * vm,
1417 vlib_packet_template_t * t,
1419 uword n_packet_data_bytes,
1420 uword min_n_buffers_each_alloc,
1423 void *vlib_packet_template_get_packet (vlib_main_t * vm,
1424 vlib_packet_template_t * t,
1428 vlib_packet_template_free (vlib_main_t * vm, vlib_packet_template_t * t)
1430 vec_free (t->packet_data);
1434 vlib_buffer_space_left_at_end (vlib_main_t * vm, vlib_buffer_t * b)
1436 return b->data + vlib_buffer_get_default_data_size (vm) -
1437 ((u8 *) vlib_buffer_get_current (b) + b->current_length);
1441 vlib_buffer_chain_linearize (vlib_main_t * vm, vlib_buffer_t * b)
1443 vlib_buffer_t *db = b, *sb, *first = b;
1445 u32 bytes_left = 0, data_size;
1446 u16 src_left, dst_left, n_buffers = 1;
1450 if (PREDICT_TRUE ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0))
1453 data_size = vlib_buffer_get_default_data_size (vm);
1455 dst_left = vlib_buffer_space_left_at_end (vm, b);
1457 while (b->flags & VLIB_BUFFER_NEXT_PRESENT)
1459 b = vlib_get_buffer (vm, b->next_buffer);
1460 if (b->ref_count > 1)
1462 bytes_left += b->current_length;
1466 /* if buffer is cloned, create completely new chain - unless everything fits
1467 * into one buffer */
1468 if (is_cloned && bytes_left >= dst_left)
1471 u32 space_needed = bytes_left - dst_left;
1474 if (vlib_buffer_alloc (vm, &tail, 1) == 0)
1479 b = vlib_get_buffer (vm, tail);
1481 while (len < space_needed)
1484 if (vlib_buffer_alloc (vm, &bi, 1) == 0)
1486 vlib_buffer_free_one (vm, tail);
1489 b->flags = VLIB_BUFFER_NEXT_PRESENT;
1490 b->next_buffer = bi;
1491 b = vlib_get_buffer (vm, bi);
1495 sb = vlib_get_buffer (vm, first->next_buffer);
1496 to_free = first->next_buffer;
1497 first->next_buffer = tail;
1500 sb = vlib_get_buffer (vm, first->next_buffer);
1502 src_left = sb->current_length;
1503 sp = vlib_buffer_get_current (sb);
1504 dp = vlib_buffer_get_tail (db);
1512 db->current_length = dp - (u8 *) vlib_buffer_get_current (db);
1513 ASSERT (db->flags & VLIB_BUFFER_NEXT_PRESENT);
1514 db = vlib_get_buffer (vm, db->next_buffer);
1515 dst_left = data_size;
1516 if (db->current_data > 0)
1518 db->current_data = 0;
1522 dst_left += -db->current_data;
1524 dp = vlib_buffer_get_current (db);
1527 while (src_left == 0)
1529 ASSERT (sb->flags & VLIB_BUFFER_NEXT_PRESENT);
1530 sb = vlib_get_buffer (vm, sb->next_buffer);
1531 src_left = sb->current_length;
1532 sp = vlib_buffer_get_current (sb);
1535 bytes_to_copy = clib_min (dst_left, src_left);
1540 bytes_to_copy = clib_min (bytes_to_copy, sp - dp);
1542 clib_memcpy_fast (dp, sp, bytes_to_copy);
1545 src_left -= bytes_to_copy;
1546 dst_left -= bytes_to_copy;
1547 dp += bytes_to_copy;
1548 sp += bytes_to_copy;
1549 bytes_left -= bytes_to_copy;
1552 db->current_data = 0;
1553 db->current_length = dp - (u8 *) vlib_buffer_get_current (db);
1555 if (is_cloned && to_free)
1556 vlib_buffer_free_one (vm, to_free);
1559 if (db->flags & VLIB_BUFFER_NEXT_PRESENT)
1560 vlib_buffer_free_one (vm, db->next_buffer);
1561 db->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
1564 while (b->flags & VLIB_BUFFER_NEXT_PRESENT)
1566 b = vlib_get_buffer (vm, b->next_buffer);
1571 first->flags &= ~VLIB_BUFFER_TOTAL_LENGTH_VALID;
1576 #endif /* included_vlib_buffer_funcs_h */
1579 * fd.io coding-style-patch-verification: ON
1582 * eval: (c-set-style "gnu")