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 */
49 #include <vlib/config.h> /* for __PRE_DATA_SIZE */
50 #define VLIB_BUFFER_DATA_SIZE (2048)
51 #define VLIB_BUFFER_PRE_DATA_SIZE __PRE_DATA_SIZE
54 vlib buffer structure definition and a few select
55 access methods. This structure and the buffer allocation
56 mechanism should perhaps live in vnet, but it would take a lot
57 of typing to make it so.
60 /* VLIB buffer representation. */
63 CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
64 /* Offset within data[] that we are currently processing.
65 If negative current header points into predata area. */
66 i16 current_data; /**< signed offset in data[], pre_data[]
67 that we are currently processing.
68 If negative current header points into predata area.
70 u16 current_length; /**< Nbytes between current data and
71 the end of this buffer.
73 u32 flags; /**< buffer flags:
74 <br> VLIB_BUFFER_IS_TRACED: trace this buffer.
75 <br> VLIB_BUFFER_NEXT_PRESENT: this is a multi-chunk buffer.
76 <br> VLIB_BUFFER_TOTAL_LENGTH_VALID: as it says
77 <br> VLIB_BUFFER_REPL_FAIL: packet replication failure
78 <br> VLIB_BUFFER_RECYCLE: as it says
79 <br> VLIB_BUFFER_FLOW_REPORT: buffer is a flow report,
80 set to avoid adding it to a flow report
81 <br> VLIB_BUFFER_FLAG_USER(n): user-defined bit N
83 #define VLIB_BUFFER_IS_TRACED (1 << 0)
84 #define VLIB_BUFFER_LOG2_NEXT_PRESENT (1)
85 #define VLIB_BUFFER_NEXT_PRESENT (1 << VLIB_BUFFER_LOG2_NEXT_PRESENT)
86 #define VLIB_BUFFER_IS_RECYCLED (1 << 2)
87 #define VLIB_BUFFER_TOTAL_LENGTH_VALID (1 << 3)
88 #define VLIB_BUFFER_REPL_FAIL (1 << 4)
89 #define VLIB_BUFFER_RECYCLE (1 << 5)
90 #define VLIB_BUFFER_FLOW_REPORT (1 << 6)
92 /* User defined buffer flags. */
93 #define LOG2_VLIB_BUFFER_FLAG_USER(n) (32 - (n))
94 #define VLIB_BUFFER_FLAG_USER(n) (1 << LOG2_VLIB_BUFFER_FLAG_USER(n))
96 u32 free_list_index; /**< Buffer free list that this buffer was
97 allocated from and will be freed to.
100 u32 total_length_not_including_first_buffer;
101 /**< Only valid for first buffer in chain. Current length plus
102 total length given here give total number of bytes in buffer chain.
105 u32 next_buffer; /**< Next buffer for this linked-list of buffers.
106 Only valid if VLIB_BUFFER_NEXT_PRESENT flag is set.
109 vlib_error_t error; /**< Error code for buffers to be enqueued
112 u32 current_config_index; /**< Used by feature subgraph arcs to
113 visit enabled feature nodes
116 u8 feature_arc_index; /**< Used to identify feature arcs by intermediate
120 u8 dont_waste_me[3]; /**< Available space in the (precious)
121 first 32 octets of buffer metadata
122 Before allocating any of it, discussion required!
125 u32 opaque[8]; /**< Opaque data used by sub-graphs for their own purposes.
126 See .../vnet/vnet/buffer.h
128 CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
130 u32 trace_index; /**< Specifies index into trace buffer
131 if VLIB_PACKET_IS_TRACED flag is set.
133 u32 recycle_count; /**< Used by L2 path recycle code */
134 u32 opaque2[14]; /**< More opaque data, currently unused */
136 /***** end of second cache line */
137 CLIB_CACHE_LINE_ALIGN_MARK (cacheline2);
138 u8 pre_data[VLIB_BUFFER_PRE_DATA_SIZE]; /**< Space for inserting data
140 Packet rewrite string will be
141 rewritten backwards and may extend
142 back before buffer->data[0].
143 Must come directly before packet data.
146 u8 data[0]; /**< Packet data. Hardware DMA here */
147 } vlib_buffer_t; /* Must be a multiple of 64B. */
149 #define VLIB_BUFFER_HDR_SIZE (sizeof(vlib_buffer_t) - VLIB_BUFFER_PRE_DATA_SIZE)
151 /** \brief Prefetch buffer metadata.
152 The first 64 bytes of buffer contains most header information
154 @param b - (vlib_buffer_t *) pointer to the buffer
155 @param type - LOAD, STORE. In most cases, STORE is the right answer
158 #define vlib_prefetch_buffer_header(b,type) CLIB_PREFETCH (b, 64, type)
160 always_inline vlib_buffer_t *
161 vlib_buffer_next_contiguous (vlib_buffer_t * b, u32 buffer_bytes)
163 return (void *) (b + 1) + buffer_bytes;
167 vlib_buffer_struct_is_sane (vlib_buffer_t * b)
169 ASSERT (sizeof (b[0]) % 64 == 0);
171 /* Rewrite data must be before and contiguous with packet data. */
172 ASSERT (b->pre_data + VLIB_BUFFER_PRE_DATA_SIZE == b->data);
175 /** \brief Get pointer to current data to process
177 @param b - (vlib_buffer_t *) pointer to the buffer
178 @return - (void *) (b->data + b->current_data)
182 vlib_buffer_get_current (vlib_buffer_t * b)
185 ASSERT ((signed) b->current_data >= (signed) -VLIB_BUFFER_PRE_DATA_SIZE);
186 return b->data + b->current_data;
189 /** \brief Advance current data pointer by the supplied (signed!) amount
191 @param b - (vlib_buffer_t *) pointer to the buffer
192 @param l - (word) signed increment
195 vlib_buffer_advance (vlib_buffer_t * b, word l)
197 ASSERT (b->current_length >= l);
198 b->current_data += l;
199 b->current_length -= l;
202 /** \brief Reset current header & length to state they were in when
205 @param b - (vlib_buffer_t *) pointer to the buffer
209 vlib_buffer_reset (vlib_buffer_t * b)
211 b->current_length += clib_max (b->current_data, 0);
215 /** \brief Get pointer to buffer's opaque data array
217 @param b - (vlib_buffer_t *) pointer to the buffer
218 @return - (void *) b->opaque
221 vlib_get_buffer_opaque (vlib_buffer_t * b)
223 return (void *) b->opaque;
226 /** \brief Get pointer to buffer's opaque2 data array
228 @param b - (vlib_buffer_t *) pointer to the buffer
229 @return - (void *) b->opaque2
232 vlib_get_buffer_opaque2 (vlib_buffer_t * b)
234 return (void *) b->opaque2;
237 /* Forward declaration. */
240 typedef struct vlib_buffer_free_list_t
242 /* Template buffer used to initialize first 16 bytes of buffers
243 allocated on this free list. */
244 vlib_buffer_t buffer_init_template;
246 /* Our index into vlib_main_t's buffer_free_list_pool. */
249 /* Number of data bytes for buffers in this free list. */
252 /* Number of buffers to allocate when we need to allocate new buffers
253 from physmem heap. */
254 u32 min_n_buffers_each_physmem_alloc;
256 /* Total number of buffers allocated from this free list. */
259 /* Vector of free buffers. Each element is a byte offset into I/O heap. */
262 /* Memory chunks allocated for this free list
263 recorded here so they can be freed when free list
265 void **buffer_memory_allocated;
267 /* Free list name. */
270 /* Callback functions to initialize newly allocated buffers.
271 If null buffers are zeroed. */
272 void (*buffer_init_function) (struct vlib_main_t * vm,
273 struct vlib_buffer_free_list_t * fl,
274 u32 * buffers, u32 n_buffers);
276 /* Callback function to announce that buffers have been
277 added to the freelist */
278 void (*buffers_added_to_freelist_function)
279 (struct vlib_main_t * vm, struct vlib_buffer_free_list_t * fl);
281 uword buffer_init_function_opaque;
282 } __attribute__ ((aligned (16))) vlib_buffer_free_list_t;
286 u32 (*vlib_buffer_alloc_cb) (struct vlib_main_t * vm, u32 * buffers,
288 u32 (*vlib_buffer_alloc_from_free_list_cb) (struct vlib_main_t * vm,
289 u32 * buffers, u32 n_buffers,
290 u32 free_list_index);
291 void (*vlib_buffer_free_cb) (struct vlib_main_t * vm, u32 * buffers,
293 void (*vlib_buffer_free_no_next_cb) (struct vlib_main_t * vm, u32 * buffers,
295 void (*vlib_packet_template_init_cb) (struct vlib_main_t * vm, void *t,
297 uword n_packet_data_bytes,
299 min_n_buffers_each_physmem_alloc,
301 void (*vlib_buffer_delete_free_list_cb) (struct vlib_main_t * vm,
302 u32 free_list_index);
303 } vlib_buffer_callbacks_t;
307 /* Buffer free callback, for subversive activities */
308 u32 (*buffer_free_callback) (struct vlib_main_t * vm,
310 u32 n_buffers, u32 follow_buffer_next);
311 /* Pool of buffer free lists.
312 Multiple free lists exist for packet generator which uses
313 separate free lists for each packet stream --- so as to avoid
314 initializing static data for each packet generated. */
315 vlib_buffer_free_list_t *buffer_free_list_pool;
316 #define VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX (0)
317 #define VLIB_BUFFER_DEFAULT_FREE_LIST_BYTES VLIB_BUFFER_DATA_SIZE
319 /* Hash table mapping buffer size (rounded to next unit of
320 sizeof (vlib_buffer_t)) to free list index. */
321 uword *free_list_by_size;
323 /* Hash table mapping buffer index into number
324 0 => allocated but free, 1 => allocated and not-free.
325 If buffer index is not in hash table then this buffer
326 has never been allocated. */
327 uword *buffer_known_hash;
329 /* List of free-lists needing Blue Light Special announcements */
330 vlib_buffer_free_list_t **announce_list;
333 vlib_buffer_callbacks_t cb;
334 int extern_buffer_mgmt;
335 } vlib_buffer_main_t;
337 void vlib_buffer_cb_init (struct vlib_main_t *vm);
338 int vlib_buffer_cb_register (struct vlib_main_t *vm,
339 vlib_buffer_callbacks_t * cb);
343 struct vlib_main_t *vlib_main;
345 u32 first_buffer, last_buffer;
351 /* Total accumulated bytes in chain starting with first_buffer. */
352 u32 n_total_data_bytes;
354 /* Max number of bytes to accumulate in chain starting with first_buffer.
355 As this limit is reached buffers are enqueued to next node. */
356 u32 max_n_data_bytes_per_chain;
358 /* Next node to enqueue buffers to relative to current process node. */
361 /* Free list to use to allocate new buffers. */
367 /* CLIB fifo of buffer indices waiting to be unserialized. */
370 /* Event type used to signal that RX buffers have been added to fifo. */
371 uword ready_one_time_event;
374 } vlib_serialize_buffer_main_t;
376 void serialize_open_vlib_buffer (serialize_main_t * m, struct vlib_main_t *vm,
377 vlib_serialize_buffer_main_t * sm);
378 void unserialize_open_vlib_buffer (serialize_main_t * m,
379 struct vlib_main_t *vm,
380 vlib_serialize_buffer_main_t * sm);
382 u32 serialize_close_vlib_buffer (serialize_main_t * m);
383 void unserialize_close_vlib_buffer (serialize_main_t * m);
384 void *vlib_set_buffer_free_callback (struct vlib_main_t *vm, void *fp);
387 serialize_vlib_buffer_n_bytes (serialize_main_t * m)
389 serialize_stream_t *s = &m->stream;
390 vlib_serialize_buffer_main_t *sm
391 = uword_to_pointer (m->stream.data_function_opaque,
392 vlib_serialize_buffer_main_t *);
393 return sm->tx.n_total_data_bytes + s->current_buffer_index +
394 vec_len (s->overflow_buffer);
400 /** \brief Compile time buffer trajectory tracing option
401 Turn this on if you run into "bad monkey" contexts,
402 and you want to know exactly which nodes they've visited...
405 #define VLIB_BUFFER_TRACE_TRAJECTORY 0
407 #if VLIB_BUFFER_TRACE_TRAJECTORY > 0
408 #define VLIB_BUFFER_TRACE_TRAJECTORY_INIT(b) (b)->pre_data[0]=0
410 #define VLIB_BUFFER_TRACE_TRAJECTORY_INIT(b)
411 #endif /* VLIB_BUFFER_TRACE_TRAJECTORY */
413 #endif /* included_vlib_buffer_h */
416 * fd.io coding-style-patch-verification: ON
419 * eval: (c-set-style "gnu")