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_VEC256
78 b->as_u8x32[0] = bt->as_u8x32[0];
79 b->as_u8x32[1] = bt->as_u8x32[1];
80 #elif defined (CLIB_HAVE_VEC128)
81 b->as_u8x16[0] = bt->as_u8x16[0];
82 b->as_u8x16[1] = bt->as_u8x16[1];
83 b->as_u8x16[2] = bt->as_u8x16[2];
84 b->as_u8x16[3] = bt->as_u8x16[3];
86 clib_memcpy_fast (b, bt, 64);
90 /** \brief Translate array of buffer indices into buffer pointers with offset
92 @param vm - (vlib_main_t *) vlib main data structure pointer
93 @param bi - (u32 *) array of buffer indices
94 @param b - (void **) array to store buffer pointers
95 @param count - (uword) number of elements
96 @param offset - (i32) offset applied to each pointer
98 static_always_inline void
99 vlib_get_buffers_with_offset (vlib_main_t * vm, u32 * bi, void **b, int count,
102 uword buffer_mem_start = vm->buffer_main->buffer_mem_start;
103 #ifdef CLIB_HAVE_VEC256
104 u64x4 off = u64x4_splat (buffer_mem_start + offset);
105 /* if count is not const, compiler will not unroll while loop
106 se we maintain two-in-parallel variant */
109 u64x4 b0 = u32x4_extend_to_u64x4 (u32x4_load_unaligned (bi));
110 u64x4 b1 = u32x4_extend_to_u64x4 (u32x4_load_unaligned (bi + 4));
111 /* shift and add to get vlib_buffer_t pointer */
112 u64x4_store_unaligned ((b0 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b);
113 u64x4_store_unaligned ((b1 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b + 4);
121 #ifdef CLIB_HAVE_VEC256
122 u64x4 b0 = u32x4_extend_to_u64x4 (u32x4_load_unaligned (bi));
123 /* shift and add to get vlib_buffer_t pointer */
124 u64x4_store_unaligned ((b0 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b);
125 #elif defined (CLIB_HAVE_VEC128)
126 u64x2 off = u64x2_splat (buffer_mem_start + offset);
127 u32x4 bi4 = u32x4_load_unaligned (bi);
128 u64x2 b0 = u32x4_extend_to_u64x2 ((u32x4) bi4);
129 #if defined (__aarch64__)
130 u64x2 b1 = u32x4_extend_to_u64x2_high ((u32x4) bi4);
132 bi4 = u32x4_shuffle (bi4, 2, 3, 0, 1);
133 u64x2 b1 = u32x4_extend_to_u64x2 ((u32x4) bi4);
135 u64x2_store_unaligned ((b0 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b);
136 u64x2_store_unaligned ((b1 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b + 2);
138 b[0] = ((u8 *) vlib_get_buffer (vm, bi[0])) + offset;
139 b[1] = ((u8 *) vlib_get_buffer (vm, bi[1])) + offset;
140 b[2] = ((u8 *) vlib_get_buffer (vm, bi[2])) + offset;
141 b[3] = ((u8 *) vlib_get_buffer (vm, bi[3])) + offset;
149 b[0] = ((u8 *) vlib_get_buffer (vm, bi[0])) + offset;
156 /** \brief Translate array of buffer indices into buffer pointers
158 @param vm - (vlib_main_t *) vlib main data structure pointer
159 @param bi - (u32 *) array of buffer indices
160 @param b - (vlib_buffer_t **) array to store buffer pointers
161 @param count - (uword) number of elements
164 static_always_inline void
165 vlib_get_buffers (vlib_main_t * vm, u32 * bi, vlib_buffer_t ** b, int count)
167 vlib_get_buffers_with_offset (vm, bi, (void **) b, count, 0);
170 /** \brief Translate buffer pointer into buffer index
172 @param vm - (vlib_main_t *) vlib main data structure pointer
173 @param p - (void *) buffer pointer
174 @return - (u32) buffer index
178 vlib_get_buffer_index (vlib_main_t * vm, void *p)
180 vlib_buffer_main_t *bm = vm->buffer_main;
181 uword offset = pointer_to_uword (p) - bm->buffer_mem_start;
182 ASSERT (pointer_to_uword (p) >= bm->buffer_mem_start);
183 ASSERT (offset < bm->buffer_mem_size);
184 ASSERT ((offset % (1 << CLIB_LOG2_CACHE_LINE_BYTES)) == 0);
185 return offset >> CLIB_LOG2_CACHE_LINE_BYTES;
188 /** \brief Translate array of buffer pointers into buffer indices with offset
190 @param vm - (vlib_main_t *) vlib main data structure pointer
191 @param b - (void **) array of buffer pointers
192 @param bi - (u32 *) array to store buffer indices
193 @param count - (uword) number of elements
194 @param offset - (i32) offset applied to each pointer
196 static_always_inline void
197 vlib_get_buffer_indices_with_offset (vlib_main_t * vm, void **b, u32 * bi,
198 uword count, i32 offset)
200 #ifdef CLIB_HAVE_VEC256
201 u32x8 mask = { 0, 2, 4, 6, 1, 3, 5, 7 };
202 u64x4 off4 = u64x4_splat (vm->buffer_main->buffer_mem_start - offset);
206 /* load 4 pointers into 256-bit register */
207 u64x4 v0 = u64x4_load_unaligned (b);
208 u64x4 v1 = u64x4_load_unaligned (b + 4);
214 v0 >>= CLIB_LOG2_CACHE_LINE_BYTES;
215 v1 >>= CLIB_LOG2_CACHE_LINE_BYTES;
217 /* permute 256-bit register so lower u32s of each buffer index are
218 * placed into lower 128-bits */
219 v2 = u32x8_permute ((u32x8) v0, mask);
220 v3 = u32x8_permute ((u32x8) v1, mask);
222 /* extract lower 128-bits and save them to the array of buffer indices */
223 u32x4_store_unaligned (u32x8_extract_lo (v2), bi);
224 u32x4_store_unaligned (u32x8_extract_lo (v3), bi + 4);
232 /* equivalent non-nector implementation */
233 bi[0] = vlib_get_buffer_index (vm, ((u8 *) b[0]) + offset);
234 bi[1] = vlib_get_buffer_index (vm, ((u8 *) b[1]) + offset);
235 bi[2] = vlib_get_buffer_index (vm, ((u8 *) b[2]) + offset);
236 bi[3] = vlib_get_buffer_index (vm, ((u8 *) b[3]) + offset);
243 bi[0] = vlib_get_buffer_index (vm, ((u8 *) b[0]) + offset);
250 /** \brief Translate array of buffer pointers into buffer indices
252 @param vm - (vlib_main_t *) vlib main data structure pointer
253 @param b - (vlib_buffer_t **) array of buffer pointers
254 @param bi - (u32 *) array to store buffer indices
255 @param count - (uword) number of elements
257 static_always_inline void
258 vlib_get_buffer_indices (vlib_main_t * vm, vlib_buffer_t ** b, u32 * bi,
261 vlib_get_buffer_indices_with_offset (vm, (void **) b, bi, count, 0);
264 /** \brief Get next buffer in buffer linklist, or zero for end of list.
266 @param vm - (vlib_main_t *) vlib main data structure pointer
267 @param b - (void *) buffer pointer
268 @return - (vlib_buffer_t *) next buffer, or NULL
270 always_inline vlib_buffer_t *
271 vlib_get_next_buffer (vlib_main_t * vm, vlib_buffer_t * b)
273 return (b->flags & VLIB_BUFFER_NEXT_PRESENT
274 ? vlib_get_buffer (vm, b->next_buffer) : 0);
277 uword vlib_buffer_length_in_chain_slow_path (vlib_main_t * vm,
278 vlib_buffer_t * b_first);
280 /** \brief Get length in bytes of the buffer chain
282 @param vm - (vlib_main_t *) vlib main data structure pointer
283 @param b - (void *) buffer pointer
284 @return - (uword) length of buffer chain
287 vlib_buffer_length_in_chain (vlib_main_t * vm, vlib_buffer_t * b)
289 uword len = b->current_length;
291 if (PREDICT_TRUE ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0))
294 if (PREDICT_TRUE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID))
295 return len + b->total_length_not_including_first_buffer;
297 return vlib_buffer_length_in_chain_slow_path (vm, b);
300 /** \brief Get length in bytes of the buffer index buffer chain
302 @param vm - (vlib_main_t *) vlib main data structure pointer
303 @param bi - (u32) buffer index
304 @return - (uword) length of buffer chain
307 vlib_buffer_index_length_in_chain (vlib_main_t * vm, u32 bi)
309 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
310 return vlib_buffer_length_in_chain (vm, b);
313 /** \brief Copy buffer contents to memory
315 @param vm - (vlib_main_t *) vlib main data structure pointer
316 @param buffer_index - (u32) buffer index
317 @param contents - (u8 *) memory, <strong>must be large enough</strong>
318 @return - (uword) length of buffer chain
321 vlib_buffer_contents (vlib_main_t * vm, u32 buffer_index, u8 * contents)
323 uword content_len = 0;
329 b = vlib_get_buffer (vm, buffer_index);
330 l = b->current_length;
331 clib_memcpy_fast (contents + content_len, b->data + b->current_data, l);
333 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
335 buffer_index = b->next_buffer;
342 vlib_buffer_get_pa (vlib_main_t * vm, vlib_buffer_t * b)
344 return vlib_physmem_get_pa (vm, b->data);
348 vlib_buffer_get_current_pa (vlib_main_t * vm, vlib_buffer_t * b)
350 return vlib_buffer_get_pa (vm, b) + b->current_data;
353 /** \brief Prefetch buffer metadata by buffer index
354 The first 64 bytes of buffer contains most header information
356 @param vm - (vlib_main_t *) vlib main data structure pointer
357 @param bi - (u32) buffer index
358 @param type - LOAD, STORE. In most cases, STORE is the right answer
360 /* Prefetch buffer header given index. */
361 #define vlib_prefetch_buffer_with_index(vm,bi,type) \
363 vlib_buffer_t * _b = vlib_get_buffer (vm, bi); \
364 vlib_prefetch_buffer_header (_b, type); \
369 /* Index is unknown. */
372 /* Index is known and free/allocated. */
373 VLIB_BUFFER_KNOWN_FREE,
374 VLIB_BUFFER_KNOWN_ALLOCATED,
375 } vlib_buffer_known_state_t;
377 void vlib_buffer_validate_alloc_free (vlib_main_t * vm, u32 * buffers,
379 vlib_buffer_known_state_t
382 always_inline vlib_buffer_known_state_t
383 vlib_buffer_is_known (vlib_main_t * vm, u32 buffer_index)
385 vlib_buffer_main_t *bm = vm->buffer_main;
387 clib_spinlock_lock (&bm->buffer_known_hash_lockp);
388 uword *p = hash_get (bm->buffer_known_hash, buffer_index);
389 clib_spinlock_unlock (&bm->buffer_known_hash_lockp);
390 return p ? p[0] : VLIB_BUFFER_UNKNOWN;
394 vlib_buffer_set_known_state (vlib_main_t * vm, u32 buffer_index,
395 vlib_buffer_known_state_t state)
397 vlib_buffer_main_t *bm = vm->buffer_main;
399 clib_spinlock_lock (&bm->buffer_known_hash_lockp);
400 hash_set (bm->buffer_known_hash, buffer_index, state);
401 clib_spinlock_unlock (&bm->buffer_known_hash_lockp);
404 /* Validates sanity of a single buffer.
405 Returns format'ed vector with error message if any. */
406 u8 *vlib_validate_buffer (vlib_main_t * vm, u32 buffer_index,
410 vlib_buffer_round_size (u32 size)
412 return round_pow2 (size, sizeof (vlib_buffer_t));
415 /** \brief Allocate buffers from specific freelist into supplied array
417 @param vm - (vlib_main_t *) vlib main data structure pointer
418 @param buffers - (u32 * ) buffer index array
419 @param n_buffers - (u32) number of buffers requested
420 @return - (u32) number of buffers actually allocated, may be
421 less than the number requested or zero
424 vlib_buffer_alloc_from_free_list (vlib_main_t * vm,
427 vlib_buffer_free_list_index_t index)
429 vlib_buffer_free_list_t *fl;
430 vlib_buffer_main_t *bm = vm->buffer_main;
434 ASSERT (bm->cb.vlib_buffer_fill_free_list_cb);
436 fl = pool_elt_at_index (vm->buffer_free_list_pool, index);
438 len = vec_len (fl->buffers);
440 if (PREDICT_FALSE (len < n_buffers))
442 bm->cb.vlib_buffer_fill_free_list_cb (vm, fl, n_buffers);
443 if (PREDICT_FALSE ((len = vec_len (fl->buffers)) == 0))
446 /* even if fill free list didn't manage to refill free list
447 we should give what we have */
448 n_buffers = clib_min (len, n_buffers);
450 /* following code is intentionaly duplicated to allow compiler
451 to optimize fast path when n_buffers is constant value */
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 src = fl->buffers + len - n_buffers;
464 vlib_buffer_copy_indices (buffers, src, n_buffers);
465 _vec_len (fl->buffers) -= n_buffers;
467 /* Verify that buffers are known free. */
468 vlib_buffer_validate_alloc_free (vm, buffers, n_buffers,
469 VLIB_BUFFER_KNOWN_FREE);
474 /** \brief Allocate buffers into supplied array
476 @param vm - (vlib_main_t *) vlib main data structure pointer
477 @param buffers - (u32 * ) buffer index array
478 @param n_buffers - (u32) number of buffers requested
479 @return - (u32) number of buffers actually allocated, may be
480 less than the number requested or zero
483 vlib_buffer_alloc (vlib_main_t * vm, u32 * buffers, u32 n_buffers)
485 return vlib_buffer_alloc_from_free_list (vm, buffers, n_buffers,
486 VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);
489 /** \brief Allocate buffers into ring
491 @param vm - (vlib_main_t *) vlib main data structure pointer
492 @param buffers - (u32 * ) buffer index ring
493 @param start - (u32) first slot in the ring
494 @param ring_size - (u32) ring size
495 @param n_buffers - (u32) number of buffers requested
496 @return - (u32) number of buffers actually allocated, may be
497 less than the number requested or zero
500 vlib_buffer_alloc_to_ring (vlib_main_t * vm, u32 * ring, u32 start,
501 u32 ring_size, u32 n_buffers)
505 ASSERT (n_buffers <= ring_size);
507 if (PREDICT_TRUE (start + n_buffers <= ring_size))
508 return vlib_buffer_alloc (vm, ring + start, n_buffers);
510 n_alloc = vlib_buffer_alloc (vm, ring + start, ring_size - start);
512 if (PREDICT_TRUE (n_alloc == ring_size - start))
513 n_alloc += vlib_buffer_alloc (vm, ring, n_buffers - n_alloc);
518 /** \brief Free buffers
519 Frees the entire buffer chain for each buffer
521 @param vm - (vlib_main_t *) vlib main data structure pointer
522 @param buffers - (u32 * ) buffer index array
523 @param n_buffers - (u32) number of buffers to free
527 vlib_buffer_free (vlib_main_t * vm,
528 /* pointer to first buffer */
530 /* number of buffers to free */
533 vlib_buffer_main_t *bm = vm->buffer_main;
535 ASSERT (bm->cb.vlib_buffer_free_cb);
537 return bm->cb.vlib_buffer_free_cb (vm, buffers, n_buffers);
540 /** \brief Free buffers, does not free the buffer chain for each buffer
542 @param vm - (vlib_main_t *) vlib main data structure pointer
543 @param buffers - (u32 * ) buffer index array
544 @param n_buffers - (u32) number of buffers to free
548 vlib_buffer_free_no_next (vlib_main_t * vm,
549 /* pointer to first buffer */
551 /* number of buffers to free */
554 vlib_buffer_main_t *bm = vm->buffer_main;
556 ASSERT (bm->cb.vlib_buffer_free_no_next_cb);
558 return bm->cb.vlib_buffer_free_no_next_cb (vm, buffers, n_buffers);
561 /** \brief Free one buffer
562 Shorthand to free a single buffer chain.
564 @param vm - (vlib_main_t *) vlib main data structure pointer
565 @param buffer_index - (u32) buffer index to free
568 vlib_buffer_free_one (vlib_main_t * vm, u32 buffer_index)
570 vlib_buffer_free (vm, &buffer_index, /* n_buffers */ 1);
573 /** \brief Free buffers from ring
575 @param vm - (vlib_main_t *) vlib main data structure pointer
576 @param buffers - (u32 * ) buffer index ring
577 @param start - (u32) first slot in the ring
578 @param ring_size - (u32) ring size
579 @param n_buffers - (u32) number of buffers
582 vlib_buffer_free_from_ring (vlib_main_t * vm, u32 * ring, u32 start,
583 u32 ring_size, u32 n_buffers)
585 ASSERT (n_buffers <= ring_size);
587 if (PREDICT_TRUE (start + n_buffers <= ring_size))
589 vlib_buffer_free (vm, ring + start, n_buffers);
593 vlib_buffer_free (vm, ring + start, ring_size - start);
594 vlib_buffer_free (vm, ring, n_buffers - (ring_size - start));
598 /** \brief Free buffers from ring without freeing tail buffers
600 @param vm - (vlib_main_t *) vlib main data structure pointer
601 @param buffers - (u32 * ) buffer index ring
602 @param start - (u32) first slot in the ring
603 @param ring_size - (u32) ring size
604 @param n_buffers - (u32) number of buffers
607 vlib_buffer_free_from_ring_no_next (vlib_main_t * vm, u32 * ring, u32 start,
608 u32 ring_size, u32 n_buffers)
610 ASSERT (n_buffers <= ring_size);
612 if (PREDICT_TRUE (start + n_buffers <= ring_size))
614 vlib_buffer_free_no_next (vm, ring + start, n_buffers);
618 vlib_buffer_free_no_next (vm, ring + start, ring_size - start);
619 vlib_buffer_free_no_next (vm, ring, n_buffers - (ring_size - start));
623 /* Add/delete buffer free lists. */
624 vlib_buffer_free_list_index_t vlib_buffer_create_free_list (vlib_main_t * vm,
628 /* Append given data to end of buffer, possibly allocating new buffers. */
629 int vlib_buffer_add_data (vlib_main_t * vm, u32 * buffer_index, void *data,
632 /* duplicate all buffers in chain */
633 always_inline vlib_buffer_t *
634 vlib_buffer_copy (vlib_main_t * vm, vlib_buffer_t * b)
636 vlib_buffer_t *s, *d, *fd;
637 uword n_alloc, n_buffers = 1;
638 u32 flag_mask = VLIB_BUFFER_NEXT_PRESENT | VLIB_BUFFER_TOTAL_LENGTH_VALID;
642 while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
645 s = vlib_get_buffer (vm, s->next_buffer);
647 u32 new_buffers[n_buffers];
649 n_alloc = vlib_buffer_alloc (vm, new_buffers, n_buffers);
651 /* No guarantee that we'll get all the buffers we asked for */
652 if (PREDICT_FALSE (n_alloc < n_buffers))
655 vlib_buffer_free (vm, new_buffers, n_alloc);
661 fd = d = vlib_get_buffer (vm, new_buffers[0]);
662 d->current_data = s->current_data;
663 d->current_length = s->current_length;
664 d->flags = s->flags & flag_mask;
665 d->total_length_not_including_first_buffer =
666 s->total_length_not_including_first_buffer;
667 clib_memcpy_fast (d->opaque, s->opaque, sizeof (s->opaque));
668 clib_memcpy_fast (d->opaque2, s->opaque2, sizeof (s->opaque2));
669 clib_memcpy_fast (vlib_buffer_get_current (d),
670 vlib_buffer_get_current (s), s->current_length);
673 for (i = 1; i < n_buffers; i++)
676 d->next_buffer = new_buffers[i];
678 s = vlib_get_buffer (vm, s->next_buffer);
679 d = vlib_get_buffer (vm, new_buffers[i]);
680 d->current_data = s->current_data;
681 d->current_length = s->current_length;
682 clib_memcpy_fast (vlib_buffer_get_current (d),
683 vlib_buffer_get_current (s), s->current_length);
684 d->flags = s->flags & flag_mask;
690 /** \brief Create a maximum of 256 clones of buffer and store them
691 in the supplied array
693 @param vm - (vlib_main_t *) vlib main data structure pointer
694 @param src_buffer - (u32) source buffer index
695 @param buffers - (u32 * ) buffer index array
696 @param n_buffers - (u16) number of buffer clones requested (<=256)
697 @param head_end_offset - (u16) offset relative to current position
698 where packet head ends
699 @return - (u16) number of buffers actually cloned, may be
700 less than the number requested or zero
703 vlib_buffer_clone_256 (vlib_main_t * vm, u32 src_buffer, u32 * buffers,
704 u16 n_buffers, u16 head_end_offset)
707 vlib_buffer_t *s = vlib_get_buffer (vm, src_buffer);
709 ASSERT (s->n_add_refs == 0);
711 ASSERT (n_buffers <= 256);
713 if (s->current_length <= head_end_offset + CLIB_CACHE_LINE_BYTES * 2)
715 buffers[0] = src_buffer;
716 for (i = 1; i < n_buffers; i++)
719 d = vlib_buffer_copy (vm, s);
722 buffers[i] = vlib_get_buffer_index (vm, d);
728 if (PREDICT_FALSE (n_buffers == 1))
730 buffers[0] = src_buffer;
734 n_buffers = vlib_buffer_alloc (vm, buffers, n_buffers);
736 for (i = 0; i < n_buffers; i++)
738 vlib_buffer_t *d = vlib_get_buffer (vm, buffers[i]);
739 d->current_data = s->current_data;
740 d->current_length = head_end_offset;
741 d->total_length_not_including_first_buffer = s->current_length -
743 if (PREDICT_FALSE (s->flags & VLIB_BUFFER_NEXT_PRESENT))
745 d->total_length_not_including_first_buffer +=
746 s->total_length_not_including_first_buffer;
748 d->flags = s->flags | VLIB_BUFFER_NEXT_PRESENT;
749 d->flags &= ~VLIB_BUFFER_EXT_HDR_VALID;
750 clib_memcpy_fast (d->opaque, s->opaque, sizeof (s->opaque));
751 clib_memcpy_fast (d->opaque2, s->opaque2, sizeof (s->opaque2));
752 clib_memcpy_fast (vlib_buffer_get_current (d),
753 vlib_buffer_get_current (s), head_end_offset);
754 d->next_buffer = src_buffer;
756 vlib_buffer_advance (s, head_end_offset);
757 s->n_add_refs = n_buffers - 1;
758 while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
760 s = vlib_get_buffer (vm, s->next_buffer);
761 s->n_add_refs = n_buffers - 1;
767 /** \brief Create multiple clones of buffer and store them
768 in the supplied array
770 @param vm - (vlib_main_t *) vlib main data structure pointer
771 @param src_buffer - (u32) source buffer index
772 @param buffers - (u32 * ) buffer index array
773 @param n_buffers - (u16) number of buffer clones requested (<=256)
774 @param head_end_offset - (u16) offset relative to current position
775 where packet head ends
776 @return - (u16) number of buffers actually cloned, may be
777 less than the number requested or zero
780 vlib_buffer_clone (vlib_main_t * vm, u32 src_buffer, u32 * buffers,
781 u16 n_buffers, u16 head_end_offset)
783 vlib_buffer_t *s = vlib_get_buffer (vm, src_buffer);
786 while (n_buffers > 256)
789 copy = vlib_buffer_copy (vm, s);
790 n_cloned += vlib_buffer_clone_256 (vm,
791 vlib_get_buffer_index (vm, copy),
792 (buffers + n_cloned),
793 256, head_end_offset);
796 n_cloned += vlib_buffer_clone_256 (vm, src_buffer,
798 n_buffers, head_end_offset);
803 /** \brief Attach cloned tail to the buffer
805 @param vm - (vlib_main_t *) vlib main data structure pointer
806 @param head - (vlib_buffer_t *) head buffer
807 @param tail - (Vlib buffer_t *) tail buffer to clone and attach to head
811 vlib_buffer_attach_clone (vlib_main_t * vm, vlib_buffer_t * head,
812 vlib_buffer_t * tail)
814 ASSERT ((head->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
816 head->flags |= VLIB_BUFFER_NEXT_PRESENT;
817 head->flags &= ~VLIB_BUFFER_TOTAL_LENGTH_VALID;
818 head->flags &= ~VLIB_BUFFER_EXT_HDR_VALID;
819 head->flags |= (tail->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID);
820 head->next_buffer = vlib_get_buffer_index (vm, tail);
821 head->total_length_not_including_first_buffer = tail->current_length +
822 tail->total_length_not_including_first_buffer;
825 clib_atomic_add_fetch (&tail->n_add_refs, 1);
827 if (tail->flags & VLIB_BUFFER_NEXT_PRESENT)
829 tail = vlib_get_buffer (vm, tail->next_buffer);
834 /* Initializes the buffer as an empty packet with no chained buffers. */
836 vlib_buffer_chain_init (vlib_buffer_t * first)
838 first->total_length_not_including_first_buffer = 0;
839 first->current_length = 0;
840 first->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
841 first->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
844 /* The provided next_bi buffer index is appended to the end of the packet. */
845 always_inline vlib_buffer_t *
846 vlib_buffer_chain_buffer (vlib_main_t * vm, vlib_buffer_t * last, u32 next_bi)
848 vlib_buffer_t *next_buffer = vlib_get_buffer (vm, next_bi);
849 last->next_buffer = next_bi;
850 last->flags |= VLIB_BUFFER_NEXT_PRESENT;
851 next_buffer->current_length = 0;
852 next_buffer->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
856 /* Increases or decreases the packet length.
857 * It does not allocate or deallocate new buffers.
858 * Therefore, the added length must be compatible
859 * with the last buffer. */
861 vlib_buffer_chain_increase_length (vlib_buffer_t * first,
862 vlib_buffer_t * last, i32 len)
864 last->current_length += len;
866 first->total_length_not_including_first_buffer += len;
869 /* Copy data to the end of the packet and increases its length.
870 * It does not allocate new buffers.
871 * Returns the number of copied bytes. */
873 vlib_buffer_chain_append_data (vlib_main_t * vm,
874 vlib_buffer_free_list_index_t free_list_index,
875 vlib_buffer_t * first,
876 vlib_buffer_t * last, void *data, u16 data_len)
878 u32 n_buffer_bytes = VLIB_BUFFER_DATA_SIZE;
879 ASSERT (n_buffer_bytes >= last->current_length + last->current_data);
880 u16 len = clib_min (data_len,
881 n_buffer_bytes - last->current_length -
883 clib_memcpy_fast (vlib_buffer_get_current (last) + last->current_length,
885 vlib_buffer_chain_increase_length (first, last, len);
889 /* Copy data to the end of the packet and increases its length.
890 * Allocates additional buffers from the free list if necessary.
891 * Returns the number of copied bytes.
892 * 'last' value is modified whenever new buffers are allocated and
893 * chained and points to the last buffer in the chain. */
895 vlib_buffer_chain_append_data_with_alloc (vlib_main_t * vm,
896 vlib_buffer_free_list_index_t
898 vlib_buffer_t * first,
899 vlib_buffer_t ** last, void *data,
901 void vlib_buffer_chain_validate (vlib_main_t * vm, vlib_buffer_t * first);
903 format_function_t format_vlib_buffer, format_vlib_buffer_and_data,
904 format_vlib_buffer_contents;
908 /* Vector of packet data. */
911 /* Number of buffers to allocate in each call to allocator. */
912 u32 min_n_buffers_each_alloc;
914 /* Buffer free list for this template. */
915 vlib_buffer_free_list_index_t free_list_index;
920 } vlib_packet_template_t;
922 void vlib_packet_template_get_packet_helper (vlib_main_t * vm,
923 vlib_packet_template_t * t);
925 void vlib_packet_template_init (vlib_main_t * vm,
926 vlib_packet_template_t * t,
928 uword n_packet_data_bytes,
929 uword min_n_buffers_each_alloc,
932 void *vlib_packet_template_get_packet (vlib_main_t * vm,
933 vlib_packet_template_t * t,
937 vlib_packet_template_free (vlib_main_t * vm, vlib_packet_template_t * t)
939 vec_free (t->packet_data);
942 static_always_inline vlib_buffer_pool_t *
943 vlib_buffer_pool_get (vlib_main_t * vm, u8 buffer_pool_index)
945 vlib_buffer_main_t *bm = vm->buffer_main;
946 return vec_elt_at_index (bm->buffer_pools, buffer_pool_index);
950 vlib_buffer_add_to_free_list (vlib_main_t * vm,
951 vlib_buffer_free_list_t * f,
952 u32 buffer_index, u8 do_init)
954 vlib_buffer_pool_t *bp = vlib_buffer_pool_get (vm, f->buffer_pool_index);
956 b = vlib_get_buffer (vm, buffer_index);
957 if (PREDICT_TRUE (do_init))
958 clib_memset (b, 0, STRUCT_OFFSET_OF (vlib_buffer_t, template_end));
959 vec_add1_aligned (f->buffers, buffer_index, CLIB_CACHE_LINE_BYTES);
961 if (vec_len (f->buffers) > 4 * VLIB_FRAME_SIZE)
963 clib_spinlock_lock (&bp->lock);
964 /* keep last stored buffers, as they are more likely hot in the cache */
965 vec_add_aligned (bp->buffers, f->buffers, VLIB_FRAME_SIZE,
966 CLIB_CACHE_LINE_BYTES);
967 vec_delete (f->buffers, VLIB_FRAME_SIZE, 0);
968 f->n_alloc -= VLIB_FRAME_SIZE;
969 clib_spinlock_unlock (&bp->lock);
974 extern u32 *vlib_buffer_state_validation_lock;
975 extern uword *vlib_buffer_state_validation_hash;
976 extern void *vlib_buffer_state_heap;
980 vlib_validate_buffer_in_use (vlib_buffer_t * b, u32 expected)
986 oldheap = clib_mem_set_heap (vlib_buffer_state_heap);
988 while (clib_atomic_test_and_set (vlib_buffer_state_validation_lock))
991 p = hash_get (vlib_buffer_state_validation_hash, b);
993 /* If we don't know about b, declare it to be in the expected state */
996 hash_set (vlib_buffer_state_validation_hash, b, expected);
1000 if (p[0] != expected)
1002 void cj_stop (void);
1004 vlib_main_t *vm = &vlib_global_main;
1008 bi = vlib_get_buffer_index (vm, b);
1010 clib_mem_set_heap (oldheap);
1011 clib_warning ("%.6f buffer %llx (%d): %s, not %s",
1012 vlib_time_now (vm), bi,
1013 p[0] ? "busy" : "free", expected ? "busy" : "free");
1017 CLIB_MEMORY_BARRIER ();
1018 *vlib_buffer_state_validation_lock = 0;
1019 clib_mem_set_heap (oldheap);
1024 vlib_validate_buffer_set_in_use (vlib_buffer_t * b, u32 expected)
1029 oldheap = clib_mem_set_heap (vlib_buffer_state_heap);
1031 while (clib_atomic_test_and_set (vlib_buffer_state_validation_lock))
1034 hash_set (vlib_buffer_state_validation_hash, b, expected);
1036 CLIB_MEMORY_BARRIER ();
1037 *vlib_buffer_state_validation_lock = 0;
1038 clib_mem_set_heap (oldheap);
1042 /** minimum data size of first buffer in a buffer chain */
1043 #define VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE (256)
1046 * @brief compress buffer chain in a way where the first buffer is at least
1047 * VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE long
1049 * @param[in] vm - vlib_main
1050 * @param[in,out] first - first buffer in chain
1051 * @param[in,out] discard_vector - vector of buffer indexes which were removed
1055 vlib_buffer_chain_compress (vlib_main_t * vm,
1056 vlib_buffer_t * first, u32 ** discard_vector)
1058 if (first->current_length >= VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE ||
1059 !(first->flags & VLIB_BUFFER_NEXT_PRESENT))
1061 /* this is already big enough or not a chain */
1065 u32 want_first_size = clib_min (VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE,
1066 VLIB_BUFFER_DATA_SIZE -
1067 first->current_data);
1070 vlib_buffer_t *second = vlib_get_buffer (vm, first->next_buffer);
1071 u32 need = want_first_size - first->current_length;
1072 u32 amount_to_copy = clib_min (need, second->current_length);
1073 clib_memcpy_fast (((u8 *) vlib_buffer_get_current (first)) +
1074 first->current_length,
1075 vlib_buffer_get_current (second), amount_to_copy);
1076 first->current_length += amount_to_copy;
1077 second->current_data += amount_to_copy;
1078 second->current_length -= amount_to_copy;
1079 if (first->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID)
1081 first->total_length_not_including_first_buffer -= amount_to_copy;
1083 if (!second->current_length)
1085 vec_add1 (*discard_vector, first->next_buffer);
1086 if (second->flags & VLIB_BUFFER_NEXT_PRESENT)
1088 first->next_buffer = second->next_buffer;
1092 first->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
1094 second->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
1097 while ((first->current_length < want_first_size) &&
1098 (first->flags & VLIB_BUFFER_NEXT_PRESENT));
1102 * @brief linearize buffer chain - the first buffer is filled, if needed,
1103 * buffers are allocated and filled, returns free space in last buffer or
1104 * negative on failure
1106 * @param[in] vm - vlib_main
1107 * @param[in,out] first - first buffer in chain
1110 vlib_buffer_chain_linearize (vlib_main_t * vm, vlib_buffer_t * first)
1112 vlib_buffer_t *b = first;
1113 u32 buf_len = VLIB_BUFFER_DATA_SIZE;
1114 // free buffer chain starting from the second buffer
1115 int free_count = (b->flags & VLIB_BUFFER_NEXT_PRESENT) != 0;
1116 u32 chain_to_free = b->next_buffer;
1118 u32 len = vlib_buffer_length_in_chain (vm, b);
1119 u32 free_len = buf_len - b->current_data - b->current_length;
1120 int alloc_len = clib_max (len - free_len, 0); //use the free len in the first buffer
1121 int n_buffers = (alloc_len + buf_len - 1) / buf_len;
1122 u32 new_buffers[n_buffers];
1124 u32 n_alloc = vlib_buffer_alloc (vm, new_buffers, n_buffers);
1125 if (n_alloc != n_buffers)
1127 vlib_buffer_free_no_next (vm, new_buffers, n_alloc);
1131 vlib_buffer_t *s = b;
1132 while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
1134 s = vlib_get_buffer (vm, s->next_buffer);
1135 int d_free_len = buf_len - b->current_data - b->current_length;
1136 ASSERT (d_free_len >= 0);
1137 // chain buf and split write
1138 u32 copy_len = clib_min (d_free_len, s->current_length);
1139 u8 *d = vlib_buffer_put_uninit (b, copy_len);
1140 clib_memcpy (d, vlib_buffer_get_current (s), copy_len);
1141 int rest = s->current_length - copy_len;
1145 ASSERT (vlib_buffer_get_tail (b) == b->data + buf_len);
1146 ASSERT (n_buffers > 0);
1147 b = vlib_buffer_chain_buffer (vm, b, new_buffers[--n_buffers]);
1148 //make full use of the new buffers
1149 b->current_data = 0;
1150 d = vlib_buffer_put_uninit (b, rest);
1151 clib_memcpy (d, vlib_buffer_get_current (s) + copy_len, rest);
1154 vlib_buffer_free (vm, &chain_to_free, free_count);
1155 b->flags &= ~VLIB_BUFFER_TOTAL_LENGTH_VALID;
1156 if (b == first) /* no buffers addeed */
1157 b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
1158 ASSERT (len == vlib_buffer_length_in_chain (vm, first));
1159 ASSERT (n_buffers == 0);
1160 return buf_len - b->current_data - b->current_length;
1163 #endif /* included_vlib_buffer_funcs_h */
1166 * fd.io coding-style-patch-verification: ON
1169 * eval: (c-set-style "gnu")