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
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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,
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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
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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 */
48 #include <vlib/config.h> /* for __PRE_DATA_SIZE */
50 #ifdef CLIB_HAVE_VEC128
51 typedef u8x16 vlib_copy_unit_t;
53 typedef uword vlib_copy_unit_t;
57 vlib buffer structure definition and a few select
58 access methods. This structure and the buffer allocation
59 mechanism should perhaps live in vnet, but it would take a lot
60 of typing to make it so.
63 /* VLIB buffer representation. */
65 /* Offset within data[] that we are currently processing.
66 If negative current header points into predata area. */
67 i16 current_data; /**< signed offset in data[], pre_data[]
68 that we are currently processing.
69 If negative current header points into predata area.
71 u16 current_length; /**< Nbytes between current data and
72 the end of this buffer.
74 u32 flags; /**< buffer flags:
75 <br> VLIB_BUFFER_IS_TRACED: trace this buffer.
76 <br> VLIB_BUFFER_NEXT_PRESENT: this is a multi-chunk buffer.
77 <br> VLIB_BUFFER_TOTAL_LENGTH_VALID: as it says
78 <br> VLIB_BUFFER_REPL_FAIL: packet replication failure
79 <br> VLIB_BUFFER_FLAG_USER(n): user-defined bit N
81 #define VLIB_BUFFER_IS_TRACED (1 << 0)
82 #define VLIB_BUFFER_LOG2_NEXT_PRESENT (1)
83 #define VLIB_BUFFER_NEXT_PRESENT (1 << VLIB_BUFFER_LOG2_NEXT_PRESENT)
84 #define VLIB_BUFFER_IS_RECYCLED (1 << 2)
85 #define VLIB_BUFFER_TOTAL_LENGTH_VALID (1 << 3)
86 #define VLIB_BUFFER_HGSHM_USER_INDEX_VALID (1 << 4)
87 #define VLIB_BUFFER_REPL_FAIL (1 << 5)
89 /* User defined buffer flags. */
90 #define LOG2_VLIB_BUFFER_FLAG_USER(n) (32 - (n))
91 #define VLIB_BUFFER_FLAG_USER(n) (1 << LOG2_VLIB_BUFFER_FLAG_USER(n))
93 u32 free_list_index; /**< Buffer free list that this buffer was
94 allocated from and will be freed to.
97 u32 total_length_not_including_first_buffer;
98 /**< Only valid for first buffer in chain. Current length plus
99 total length given here give total number of bytes in buffer chain.
103 u32 next_buffer; /**< Next buffer for this linked-list of buffers.
104 Only valid if VLIB_BUFFER_NEXT_PRESENT flag is set.
107 u32 trace_index; /**< Specifies index into trace buffer
108 if VLIB_PACKET_IS_TRACED flag is set.
112 u32 clone_count; /**< Specifies whether this buffer should be
113 reinitialized when freed. It will be reinitialized
114 if the value is 0. This field can be used
115 as a counter or for other state during packet
116 replication. The buffer free function does not
120 vlib_error_t error; /**< Error code for buffers to be enqueued
124 u32 opaque[8]; /**< Opaque data used by sub-graphs for their own purposes.
125 See .../vnet/vnet/buffer.h
127 /***** end of first cache line */
129 u32 opaque2[16]; /**< More opaque data, in its own cache line */
131 /***** end of second cache line */
132 u8 pre_data [__PRE_DATA_SIZE]; /**< Space for inserting data
134 Packet rewrite string will be
135 rewritten backwards and may extend
136 back before buffer->data[0].
137 Must come directly before packet data.
140 #define VLIB_BUFFER_PRE_DATA_SIZE (ARRAY_LEN (((vlib_buffer_t *)0)->pre_data))
141 u8 data[0]; /**< Packet data. Hardware DMA here */
142 } vlib_buffer_t; /* Must be a multiple of 64B. */
144 /** \brief Prefetch buffer metadata.
145 The first 64 bytes of buffer contains most header information
147 @param b - (vlib_buffer_t *) pointer to the buffer
148 @param type - LOAD, STORE. In most cases, STORE is the right answer
151 #define vlib_prefetch_buffer_header(b,type) CLIB_PREFETCH (b, 64, type)
153 always_inline vlib_buffer_t *
154 vlib_buffer_next_contiguous (vlib_buffer_t * b, u32 buffer_bytes)
155 { return (void *) (b + 1) + buffer_bytes; }
158 vlib_buffer_struct_is_sane (vlib_buffer_t * b)
160 ASSERT (sizeof (b[0]) % 64 == 0);
162 /* Rewrite data must be before and contiguous with packet data. */
163 ASSERT (b->pre_data + VLIB_BUFFER_PRE_DATA_SIZE == b->data);
166 /** \brief Get pointer to current data to process
168 @param b - (vlib_buffer_t *) pointer to the buffer
169 @return - (void *) (b->data + b->current_data)
173 vlib_buffer_get_current (vlib_buffer_t * b)
176 ASSERT ((signed) b->current_data >= (signed) -VLIB_BUFFER_PRE_DATA_SIZE);
177 return b->data + b->current_data;
180 /** \brief Advance current data pointer by the supplied (signed!) amount
182 @param b - (vlib_buffer_t *) pointer to the buffer
183 @param l - (word) signed increment
186 vlib_buffer_advance (vlib_buffer_t * b, word l)
188 ASSERT (b->current_length >= l);
189 b->current_data += l;
190 b->current_length -= l;
193 /** \brief Reset current header & length to state they were in when
196 @param b - (vlib_buffer_t *) pointer to the buffer
200 vlib_buffer_reset (vlib_buffer_t * b)
202 b->current_length += clib_max (b->current_data, 0);
206 /** \brief Get pointer to buffer's opaque data array
208 @param b - (vlib_buffer_t *) pointer to the buffer
209 @return - (void *) b->opaque
212 vlib_get_buffer_opaque (vlib_buffer_t * b)
213 { return (void *) b->opaque; }
215 /** \brief Get pointer to buffer's opaque2 data array
217 @param b - (vlib_buffer_t *) pointer to the buffer
218 @return - (void *) b->opaque2
221 vlib_get_buffer_opaque2 (vlib_buffer_t * b)
222 { return (void *) b->opaque2; }
224 /* Forward declaration. */
227 typedef struct vlib_buffer_free_list_t {
228 /* Template buffer used to initialize first 16 bytes of buffers
229 allocated on this free list. */
230 vlib_buffer_t buffer_init_template;
232 /* Our index into vlib_main_t's buffer_free_list_pool. */
235 /* Number of data bytes for buffers in this free list. */
238 /* Number of buffers to allocate when we need to allocate new buffers
239 from physmem heap. */
240 u32 min_n_buffers_each_physmem_alloc;
242 /* Total number of buffers allocated from this free list. */
245 /* Vector of free buffers. Each element is a byte offset into I/O heap.
246 Aligned vectors always has naturally aligned vlib_copy_unit_t sized chunks
247 of buffer indices. Unaligned vector has any left over. This is meant to
248 speed up copy routines. */
249 u32 * aligned_buffers, * unaligned_buffers;
251 /* Memory chunks allocated for this free list
252 recorded here so they can be freed when free list
254 void ** buffer_memory_allocated;
256 /* Free list name. */
259 /* Callback functions to initialize newly allocated buffers.
260 If null buffers are zeroed. */
261 void (* buffer_init_function) (struct vlib_main_t * vm,
262 struct vlib_buffer_free_list_t * fl,
263 u32 * buffers, u32 n_buffers);
265 /* Callback function to announce that buffers have been
266 added to the freelist */
267 void (* buffers_added_to_freelist_function)
268 (struct vlib_main_t * vm,
269 struct vlib_buffer_free_list_t * fl);
271 uword buffer_init_function_opaque;
272 } __attribute__ ((aligned (16))) vlib_buffer_free_list_t;
275 /* Buffer free callback, for subversive activities */
276 u32 (*buffer_free_callback) (struct vlib_main_t *vm,
279 u32 follow_buffer_next);
280 /* Pool of buffer free lists.
281 Multiple free lists exist for packet generator which uses
282 separate free lists for each packet stream --- so as to avoid
283 initializing static data for each packet generated. */
284 vlib_buffer_free_list_t * buffer_free_list_pool;
285 #define VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX (0)
288 /* must be same as dpdk buffer size */
289 #define VLIB_BUFFER_DEFAULT_FREE_LIST_BYTES (2048)
291 #define VLIB_BUFFER_DEFAULT_FREE_LIST_BYTES (512)
294 /* Hash table mapping buffer size (rounded to next unit of
295 sizeof (vlib_buffer_t)) to free list index. */
296 uword * free_list_by_size;
298 /* Hash table mapping buffer index into number
299 0 => allocated but free, 1 => allocated and not-free.
300 If buffer index is not in hash table then this buffer
301 has never been allocated. */
302 uword * buffer_known_hash;
304 /* List of free-lists needing Blue Light Special announcements */
305 vlib_buffer_free_list_t **announce_list;
307 /* Vector of rte_mempools per socket */
309 struct rte_mempool ** pktmbuf_pools;
311 } vlib_buffer_main_t;
314 struct vlib_main_t * vlib_main;
316 u32 first_buffer, last_buffer;
320 /* Total accumulated bytes in chain starting with first_buffer. */
321 u32 n_total_data_bytes;
323 /* Max number of bytes to accumulate in chain starting with first_buffer.
324 As this limit is reached buffers are enqueued to next node. */
325 u32 max_n_data_bytes_per_chain;
327 /* Next node to enqueue buffers to relative to current process node. */
330 /* Free list to use to allocate new buffers. */
335 /* CLIB fifo of buffer indices waiting to be unserialized. */
338 /* Event type used to signal that RX buffers have been added to fifo. */
339 uword ready_one_time_event;
342 } vlib_serialize_buffer_main_t;
344 void serialize_open_vlib_buffer (serialize_main_t * m, struct vlib_main_t * vm, vlib_serialize_buffer_main_t * sm);
345 void unserialize_open_vlib_buffer (serialize_main_t * m, struct vlib_main_t * vm, vlib_serialize_buffer_main_t * sm);
347 u32 serialize_close_vlib_buffer (serialize_main_t * m);
348 void unserialize_close_vlib_buffer (serialize_main_t * m);
349 void *vlib_set_buffer_free_callback (struct vlib_main_t *vm, void *fp);
352 serialize_vlib_buffer_n_bytes (serialize_main_t * m)
354 serialize_stream_t * s = &m->stream;
355 vlib_serialize_buffer_main_t * sm
356 = uword_to_pointer (m->stream.data_function_opaque, vlib_serialize_buffer_main_t *);
357 return sm->tx.n_total_data_bytes + s->current_buffer_index + vec_len (s->overflow_buffer);
363 /** \brief Compile time buffer trajectory tracing option
364 Turn this on if you run into "bad monkey" contexts,
365 and you want to know exactly which nodes they've visited...
368 #define VLIB_BUFFER_TRACE_TRAJECTORY 0
370 #if VLIB_BUFFER_TRACE_TRAJECTORY > 0
371 #define VLIB_BUFFER_TRACE_TRAJECTORY_INIT(b) (b)->pre_data[0]=0
373 #define VLIB_BUFFER_TRACE_TRAJECTORY_INIT(b)
374 #endif /* VLIB_BUFFER_TRACE_TRAJECTORY */
376 #endif /* included_vlib_buffer_h */