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.h: VLIB buffers
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_h
41 #define included_vlib_buffer_h
43 #include <vppinfra/types.h>
44 #include <vppinfra/cache.h>
45 #include <vppinfra/serialize.h>
46 #include <vppinfra/vector.h>
47 #include <vlib/error.h> /* for vlib_error_t */
50 #include <rte_config.h>
51 #define VLIB_BUFFER_DATA_SIZE (2048)
52 #define VLIB_BUFFER_PRE_DATA_SIZE RTE_PKTMBUF_HEADROOM
54 #include <vlib/config.h> /* for __PRE_DATA_SIZE */
55 #define VLIB_BUFFER_DATA_SIZE (512)
56 #define VLIB_BUFFER_PRE_DATA_SIZE __PRE_DATA_SIZE
59 #ifdef CLIB_HAVE_VEC128
60 typedef u8x16 vlib_copy_unit_t;
62 typedef u64 vlib_copy_unit_t;
66 vlib buffer structure definition and a few select
67 access methods. This structure and the buffer allocation
68 mechanism should perhaps live in vnet, but it would take a lot
69 of typing to make it so.
72 /* VLIB buffer representation. */
74 CLIB_CACHE_LINE_ALIGN_MARK(cacheline0);
75 /* Offset within data[] that we are currently processing.
76 If negative current header points into predata area. */
77 i16 current_data; /**< signed offset in data[], pre_data[]
78 that we are currently processing.
79 If negative current header points into predata area.
81 u16 current_length; /**< Nbytes between current data and
82 the end of this buffer.
84 u32 flags; /**< buffer flags:
85 <br> VLIB_BUFFER_IS_TRACED: trace this buffer.
86 <br> VLIB_BUFFER_NEXT_PRESENT: this is a multi-chunk buffer.
87 <br> VLIB_BUFFER_TOTAL_LENGTH_VALID: as it says
88 <br> VLIB_BUFFER_REPL_FAIL: packet replication failure
89 <br> VLIB_BUFFER_FLAG_USER(n): user-defined bit N
91 #define VLIB_BUFFER_IS_TRACED (1 << 0)
92 #define VLIB_BUFFER_LOG2_NEXT_PRESENT (1)
93 #define VLIB_BUFFER_NEXT_PRESENT (1 << VLIB_BUFFER_LOG2_NEXT_PRESENT)
94 #define VLIB_BUFFER_IS_RECYCLED (1 << 2)
95 #define VLIB_BUFFER_TOTAL_LENGTH_VALID (1 << 3)
96 #define VLIB_BUFFER_HGSHM_USER_INDEX_VALID (1 << 4)
97 #define VLIB_BUFFER_REPL_FAIL (1 << 5)
99 /* User defined buffer flags. */
100 #define LOG2_VLIB_BUFFER_FLAG_USER(n) (32 - (n))
101 #define VLIB_BUFFER_FLAG_USER(n) (1 << LOG2_VLIB_BUFFER_FLAG_USER(n))
103 u32 free_list_index; /**< Buffer free list that this buffer was
104 allocated from and will be freed to.
107 u32 total_length_not_including_first_buffer;
108 /**< Only valid for first buffer in chain. Current length plus
109 total length given here give total number of bytes in buffer chain.
113 u32 next_buffer; /**< Next buffer for this linked-list of buffers.
114 Only valid if VLIB_BUFFER_NEXT_PRESENT flag is set.
117 u32 trace_index; /**< Specifies index into trace buffer
118 if VLIB_PACKET_IS_TRACED flag is set.
122 u32 clone_count; /**< Specifies whether this buffer should be
123 reinitialized when freed. It will be reinitialized
124 if the value is 0. This field can be used
125 as a counter or for other state during packet
126 replication. The buffer free function does not
130 vlib_error_t error; /**< Error code for buffers to be enqueued
134 u32 opaque[8]; /**< Opaque data used by sub-graphs for their own purposes.
135 See .../vnet/vnet/buffer.h
137 CLIB_CACHE_LINE_ALIGN_MARK(cacheline1);
139 u32 opaque2[16]; /**< More opaque data, in its own cache line */
141 /***** end of second cache line */
142 CLIB_CACHE_LINE_ALIGN_MARK(cacheline2);
143 u8 pre_data [VLIB_BUFFER_PRE_DATA_SIZE]; /**< Space for inserting data
145 Packet rewrite string will be
146 rewritten backwards and may extend
147 back before buffer->data[0].
148 Must come directly before packet data.
151 u8 data[0]; /**< Packet data. Hardware DMA here */
152 } vlib_buffer_t; /* Must be a multiple of 64B. */
154 #define VLIB_BUFFER_HDR_SIZE (sizeof(vlib_buffer_t) - VLIB_BUFFER_PRE_DATA_SIZE)
156 /** \brief Prefetch buffer metadata.
157 The first 64 bytes of buffer contains most header information
159 @param b - (vlib_buffer_t *) pointer to the buffer
160 @param type - LOAD, STORE. In most cases, STORE is the right answer
163 #define vlib_prefetch_buffer_header(b,type) CLIB_PREFETCH (b, 64, type)
165 always_inline vlib_buffer_t *
166 vlib_buffer_next_contiguous (vlib_buffer_t * b, u32 buffer_bytes)
167 { return (void *) (b + 1) + buffer_bytes; }
170 vlib_buffer_struct_is_sane (vlib_buffer_t * b)
172 ASSERT (sizeof (b[0]) % 64 == 0);
174 /* Rewrite data must be before and contiguous with packet data. */
175 ASSERT (b->pre_data + VLIB_BUFFER_PRE_DATA_SIZE == b->data);
178 /** \brief Get pointer to current data to process
180 @param b - (vlib_buffer_t *) pointer to the buffer
181 @return - (void *) (b->data + b->current_data)
185 vlib_buffer_get_current (vlib_buffer_t * b)
188 ASSERT ((signed) b->current_data >= (signed) -VLIB_BUFFER_PRE_DATA_SIZE);
189 return b->data + b->current_data;
192 /** \brief Advance current data pointer by the supplied (signed!) amount
194 @param b - (vlib_buffer_t *) pointer to the buffer
195 @param l - (word) signed increment
198 vlib_buffer_advance (vlib_buffer_t * b, word l)
200 ASSERT (b->current_length >= l);
201 b->current_data += l;
202 b->current_length -= l;
205 /** \brief Reset current header & length to state they were in when
208 @param b - (vlib_buffer_t *) pointer to the buffer
212 vlib_buffer_reset (vlib_buffer_t * b)
214 b->current_length += clib_max (b->current_data, 0);
218 /** \brief Get pointer to buffer's opaque data array
220 @param b - (vlib_buffer_t *) pointer to the buffer
221 @return - (void *) b->opaque
224 vlib_get_buffer_opaque (vlib_buffer_t * b)
225 { return (void *) b->opaque; }
227 /** \brief Get pointer to buffer's opaque2 data array
229 @param b - (vlib_buffer_t *) pointer to the buffer
230 @return - (void *) b->opaque2
233 vlib_get_buffer_opaque2 (vlib_buffer_t * b)
234 { return (void *) b->opaque2; }
236 /* Forward declaration. */
239 typedef struct vlib_buffer_free_list_t {
240 /* Template buffer used to initialize first 16 bytes of buffers
241 allocated on this free list. */
242 vlib_buffer_t buffer_init_template;
244 /* Our index into vlib_main_t's buffer_free_list_pool. */
247 /* Number of data bytes for buffers in this free list. */
250 /* Number of buffers to allocate when we need to allocate new buffers
251 from physmem heap. */
252 u32 min_n_buffers_each_physmem_alloc;
254 /* Total number of buffers allocated from this free list. */
257 /* Vector of free buffers. Each element is a byte offset into I/O heap.
258 Aligned vectors always has naturally aligned vlib_copy_unit_t sized chunks
259 of buffer indices. Unaligned vector has any left over. This is meant to
260 speed up copy routines. */
261 u32 * aligned_buffers, * unaligned_buffers;
263 /* Memory chunks allocated for this free list
264 recorded here so they can be freed when free list
266 void ** buffer_memory_allocated;
268 /* Free list name. */
271 /* Callback functions to initialize newly allocated buffers.
272 If null buffers are zeroed. */
273 void (* buffer_init_function) (struct vlib_main_t * vm,
274 struct vlib_buffer_free_list_t * fl,
275 u32 * buffers, u32 n_buffers);
277 /* Callback function to announce that buffers have been
278 added to the freelist */
279 void (* buffers_added_to_freelist_function)
280 (struct vlib_main_t * vm,
281 struct vlib_buffer_free_list_t * fl);
283 uword buffer_init_function_opaque;
284 } __attribute__ ((aligned (16))) vlib_buffer_free_list_t;
287 /* Buffer free callback, for subversive activities */
288 u32 (*buffer_free_callback) (struct vlib_main_t *vm,
291 u32 follow_buffer_next);
292 /* Pool of buffer free lists.
293 Multiple free lists exist for packet generator which uses
294 separate free lists for each packet stream --- so as to avoid
295 initializing static data for each packet generated. */
296 vlib_buffer_free_list_t * buffer_free_list_pool;
297 #define VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX (0)
298 #define VLIB_BUFFER_DEFAULT_FREE_LIST_BYTES VLIB_BUFFER_DATA_SIZE
300 /* Hash table mapping buffer size (rounded to next unit of
301 sizeof (vlib_buffer_t)) to free list index. */
302 uword * free_list_by_size;
304 /* Hash table mapping buffer index into number
305 0 => allocated but free, 1 => allocated and not-free.
306 If buffer index is not in hash table then this buffer
307 has never been allocated. */
308 uword * buffer_known_hash;
310 /* List of free-lists needing Blue Light Special announcements */
311 vlib_buffer_free_list_t **announce_list;
313 /* Vector of rte_mempools per socket */
315 struct rte_mempool ** pktmbuf_pools;
317 } vlib_buffer_main_t;
320 struct vlib_main_t * vlib_main;
322 u32 first_buffer, last_buffer;
326 /* Total accumulated bytes in chain starting with first_buffer. */
327 u32 n_total_data_bytes;
329 /* Max number of bytes to accumulate in chain starting with first_buffer.
330 As this limit is reached buffers are enqueued to next node. */
331 u32 max_n_data_bytes_per_chain;
333 /* Next node to enqueue buffers to relative to current process node. */
336 /* Free list to use to allocate new buffers. */
341 /* CLIB fifo of buffer indices waiting to be unserialized. */
344 /* Event type used to signal that RX buffers have been added to fifo. */
345 uword ready_one_time_event;
348 } vlib_serialize_buffer_main_t;
350 void serialize_open_vlib_buffer (serialize_main_t * m, struct vlib_main_t * vm, vlib_serialize_buffer_main_t * sm);
351 void unserialize_open_vlib_buffer (serialize_main_t * m, struct vlib_main_t * vm, vlib_serialize_buffer_main_t * sm);
353 u32 serialize_close_vlib_buffer (serialize_main_t * m);
354 void unserialize_close_vlib_buffer (serialize_main_t * m);
355 void *vlib_set_buffer_free_callback (struct vlib_main_t *vm, void *fp);
358 serialize_vlib_buffer_n_bytes (serialize_main_t * m)
360 serialize_stream_t * s = &m->stream;
361 vlib_serialize_buffer_main_t * sm
362 = uword_to_pointer (m->stream.data_function_opaque, vlib_serialize_buffer_main_t *);
363 return sm->tx.n_total_data_bytes + s->current_buffer_index + vec_len (s->overflow_buffer);
367 #define rte_mbuf_from_vlib_buffer(x) (((struct rte_mbuf *)x) - 1)
368 #define vlib_buffer_from_rte_mbuf(x) ((vlib_buffer_t *)(x+1))
374 /** \brief Compile time buffer trajectory tracing option
375 Turn this on if you run into "bad monkey" contexts,
376 and you want to know exactly which nodes they've visited...
379 #define VLIB_BUFFER_TRACE_TRAJECTORY 0
381 #if VLIB_BUFFER_TRACE_TRAJECTORY > 0
382 #define VLIB_BUFFER_TRACE_TRAJECTORY_INIT(b) (b)->pre_data[0]=0
384 #define VLIB_BUFFER_TRACE_TRAJECTORY_INIT(b)
385 #endif /* VLIB_BUFFER_TRACE_TRAJECTORY */
387 #endif /* included_vlib_buffer_h */