2 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2016 Nicira, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
20 #include "openvswitch/dynamic-string.h"
21 #include "netdev-dpdk.h"
22 #include "dp-packet.h"
26 dp_packet_init__(struct dp_packet *b, size_t allocated, enum dp_packet_source source)
28 dp_packet_set_allocated(b, allocated);
30 dp_packet_reset_offsets(b);
31 pkt_metadata_init(&b->md, 0);
32 dp_packet_rss_invalidate(b);
36 dp_packet_use__(struct dp_packet *b, void *base, size_t allocated,
37 enum dp_packet_source source)
39 dp_packet_set_base(b, base);
40 dp_packet_set_data(b, base);
41 dp_packet_set_size(b, 0);
43 dp_packet_init__(b, allocated, source);
46 /* Initializes 'b' as an empty dp_packet that contains the 'allocated' bytes of
47 * memory starting at 'base'. 'base' should be the first byte of a region
48 * obtained from malloc(). It will be freed (with free()) if 'b' is resized or
51 dp_packet_use(struct dp_packet *b, void *base, size_t allocated)
53 dp_packet_use__(b, base, allocated, DPBUF_MALLOC);
56 /* Initializes 'b' as an empty dp_packet that contains the 'allocated' bytes of
57 * memory starting at 'base'. 'base' should point to a buffer on the stack.
58 * (Nothing actually relies on 'base' being allocated on the stack. It could
59 * be static or malloc()'d memory. But stack space is the most common use
62 * 'base' should be appropriately aligned. Using an array of uint32_t or
63 * uint64_t for the buffer is a reasonable way to ensure appropriate alignment
64 * for 32- or 64-bit data.
66 * An dp_packet operation that requires reallocating data will copy the provided
67 * buffer into a malloc()'d buffer. Thus, it is wise to call dp_packet_uninit()
68 * on an dp_packet initialized by this function, so that if it expanded into the
69 * heap, that memory is freed. */
71 dp_packet_use_stub(struct dp_packet *b, void *base, size_t allocated)
73 dp_packet_use__(b, base, allocated, DPBUF_STUB);
76 /* Initializes 'b' as an dp_packet whose data starts at 'data' and continues for
77 * 'size' bytes. This is appropriate for an dp_packet that will be used to
78 * inspect existing data, without moving it around or reallocating it, and
79 * generally without modifying it at all.
81 * An dp_packet operation that requires reallocating data will assert-fail if this
82 * function was used to initialize it. */
84 dp_packet_use_const(struct dp_packet *b, const void *data, size_t size)
86 dp_packet_use__(b, CONST_CAST(void *, data), size, DPBUF_STACK);
87 dp_packet_set_size(b, size);
90 /* Initializes 'b' as an empty dp_packet that contains the 'allocated' bytes of
91 * memory starting at 'base'. DPDK allocated dp_packet and *data is allocated
92 * from one continous memory region, so in memory data start right after
93 * dp_packet. Therefore there is special method to free this type of
94 * buffer. dp_packet base, data and size are initialized by dpdk rcv() so no
95 * need to initialize those fields. */
97 dp_packet_init_dpdk(struct dp_packet *b, size_t allocated)
99 dp_packet_init__(b, allocated, DPBUF_DPDK);
102 /* Initializes 'b' as an empty dp_packet with an initial capacity of 'size'
105 dp_packet_init(struct dp_packet *b, size_t size)
107 dp_packet_use(b, size ? xmalloc(size) : NULL, size);
110 /* Frees memory that 'b' points to. */
112 dp_packet_uninit(struct dp_packet *b)
115 if (b->source == DPBUF_MALLOC) {
116 free(dp_packet_base(b));
117 } else if (b->source == DPBUF_DPDK) {
119 /* If this dp_packet was allocated by DPDK it must have been
120 * created as a dp_packet */
121 free_dpdk_buf((struct dp_packet*) b);
127 /* Creates and returns a new dp_packet with an initial capacity of 'size'
130 dp_packet_new(size_t size)
132 struct dp_packet *b = xmalloc(sizeof *b);
133 dp_packet_init(b, size);
137 /* Creates and returns a new dp_packet with an initial capacity of 'size +
138 * headroom' bytes, reserving the first 'headroom' bytes as headroom. */
140 dp_packet_new_with_headroom(size_t size, size_t headroom)
142 struct dp_packet *b = dp_packet_new(size + headroom);
143 dp_packet_reserve(b, headroom);
147 /* Creates and returns a new dp_packet that initially contains a copy of the
148 * 'dp_packet_size(buffer)' bytes of data starting at 'buffer->data' with no headroom or
151 dp_packet_clone(const struct dp_packet *buffer)
153 return dp_packet_clone_with_headroom(buffer, 0);
156 /* Creates and returns a new dp_packet whose data are copied from 'buffer'. The
157 * returned dp_packet will additionally have 'headroom' bytes of headroom. */
159 dp_packet_clone_with_headroom(const struct dp_packet *buffer, size_t headroom)
161 struct dp_packet *new_buffer;
163 new_buffer = dp_packet_clone_data_with_headroom(dp_packet_data(buffer),
164 dp_packet_size(buffer),
166 new_buffer->l2_pad_size = buffer->l2_pad_size;
167 new_buffer->l2_5_ofs = buffer->l2_5_ofs;
168 new_buffer->l3_ofs = buffer->l3_ofs;
169 new_buffer->l4_ofs = buffer->l4_ofs;
170 new_buffer->md = buffer->md;
172 new_buffer->mbuf.ol_flags = buffer->mbuf.ol_flags;
174 new_buffer->rss_hash_valid = buffer->rss_hash_valid;
177 if (dp_packet_rss_valid(new_buffer)) {
179 new_buffer->mbuf.hash.rss = buffer->mbuf.hash.rss;
181 new_buffer->rss_hash = buffer->rss_hash;
188 /* Creates and returns a new dp_packet that initially contains a copy of the
189 * 'size' bytes of data starting at 'data' with no headroom or tailroom. */
191 dp_packet_clone_data(const void *data, size_t size)
193 return dp_packet_clone_data_with_headroom(data, size, 0);
196 /* Creates and returns a new dp_packet that initially contains 'headroom' bytes of
197 * headroom followed by a copy of the 'size' bytes of data starting at
200 dp_packet_clone_data_with_headroom(const void *data, size_t size, size_t headroom)
202 struct dp_packet *b = dp_packet_new_with_headroom(size, headroom);
203 dp_packet_put(b, data, size);
208 dp_packet_copy__(struct dp_packet *b, uint8_t *new_base,
209 size_t new_headroom, size_t new_tailroom)
211 const uint8_t *old_base = dp_packet_base(b);
212 size_t old_headroom = dp_packet_headroom(b);
213 size_t old_tailroom = dp_packet_tailroom(b);
214 size_t copy_headroom = MIN(old_headroom, new_headroom);
215 size_t copy_tailroom = MIN(old_tailroom, new_tailroom);
217 memcpy(&new_base[new_headroom - copy_headroom],
218 &old_base[old_headroom - copy_headroom],
219 copy_headroom + dp_packet_size(b) + copy_tailroom);
222 /* Reallocates 'b' so that it has exactly 'new_headroom' and 'new_tailroom'
223 * bytes of headroom and tailroom, respectively. */
225 dp_packet_resize__(struct dp_packet *b, size_t new_headroom, size_t new_tailroom)
227 void *new_base, *new_data;
228 size_t new_allocated;
230 new_allocated = new_headroom + dp_packet_size(b) + new_tailroom;
237 if (new_headroom == dp_packet_headroom(b)) {
238 new_base = xrealloc(dp_packet_base(b), new_allocated);
240 new_base = xmalloc(new_allocated);
241 dp_packet_copy__(b, new_base, new_headroom, new_tailroom);
242 free(dp_packet_base(b));
250 b->source = DPBUF_MALLOC;
251 new_base = xmalloc(new_allocated);
252 dp_packet_copy__(b, new_base, new_headroom, new_tailroom);
259 dp_packet_set_allocated(b, new_allocated);
260 dp_packet_set_base(b, new_base);
262 new_data = (char *) new_base + new_headroom;
263 if (dp_packet_data(b) != new_data) {
264 dp_packet_set_data(b, new_data);
268 /* Ensures that 'b' has room for at least 'size' bytes at its tail end,
269 * reallocating and copying its data if necessary. Its headroom, if any, is
272 dp_packet_prealloc_tailroom(struct dp_packet *b, size_t size)
274 if (size > dp_packet_tailroom(b)) {
275 dp_packet_resize__(b, dp_packet_headroom(b), MAX(size, 64));
279 /* Ensures that 'b' has room for at least 'size' bytes at its head,
280 * reallocating and copying its data if necessary. Its tailroom, if any, is
283 dp_packet_prealloc_headroom(struct dp_packet *b, size_t size)
285 if (size > dp_packet_headroom(b)) {
286 dp_packet_resize__(b, MAX(size, 64), dp_packet_tailroom(b));
290 /* Shifts all of the data within the allocated space in 'b' by 'delta' bytes.
291 * For example, a 'delta' of 1 would cause each byte of data to move one byte
292 * forward (from address 'p' to 'p+1'), and a 'delta' of -1 would cause each
293 * byte to move one byte backward (from 'p' to 'p-1'). */
295 dp_packet_shift(struct dp_packet *b, int delta)
297 ovs_assert(delta > 0 ? delta <= dp_packet_tailroom(b)
298 : delta < 0 ? -delta <= dp_packet_headroom(b)
302 char *dst = (char *) dp_packet_data(b) + delta;
303 memmove(dst, dp_packet_data(b), dp_packet_size(b));
304 dp_packet_set_data(b, dst);
308 /* Appends 'size' bytes of data to the tail end of 'b', reallocating and
309 * copying its data if necessary. Returns a pointer to the first byte of the
310 * new data, which is left uninitialized. */
312 dp_packet_put_uninit(struct dp_packet *b, size_t size)
315 dp_packet_prealloc_tailroom(b, size);
316 p = dp_packet_tail(b);
317 dp_packet_set_size(b, dp_packet_size(b) + size);
321 /* Appends 'size' zeroed bytes to the tail end of 'b'. Data in 'b' is
322 * reallocated and copied if necessary. Returns a pointer to the first byte of
323 * the data's location in the dp_packet. */
325 dp_packet_put_zeros(struct dp_packet *b, size_t size)
327 void *dst = dp_packet_put_uninit(b, size);
328 memset(dst, 0, size);
332 /* Appends the 'size' bytes of data in 'p' to the tail end of 'b'. Data in 'b'
333 * is reallocated and copied if necessary. Returns a pointer to the first
334 * byte of the data's location in the dp_packet. */
336 dp_packet_put(struct dp_packet *b, const void *p, size_t size)
338 void *dst = dp_packet_put_uninit(b, size);
339 memcpy(dst, p, size);
343 /* Parses as many pairs of hex digits as possible (possibly separated by
344 * spaces) from the beginning of 's', appending bytes for their values to 'b'.
345 * Returns the first character of 's' that is not the first of a pair of hex
346 * digits. If 'n' is nonnull, stores the number of bytes added to 'b' in
349 dp_packet_put_hex(struct dp_packet *b, const char *s, size_t *n)
351 size_t initial_size = dp_packet_size(b);
356 s += strspn(s, " \t\r\n");
357 byte = hexits_value(s, 2, &ok);
360 *n = dp_packet_size(b) - initial_size;
362 return CONST_CAST(char *, s);
365 dp_packet_put(b, &byte, 1);
370 /* Reserves 'size' bytes of headroom so that they can be later allocated with
371 * dp_packet_push_uninit() without reallocating the dp_packet. */
373 dp_packet_reserve(struct dp_packet *b, size_t size)
375 ovs_assert(!dp_packet_size(b));
376 dp_packet_prealloc_tailroom(b, size);
377 dp_packet_set_data(b, (char*)dp_packet_data(b) + size);
380 /* Reserves 'headroom' bytes at the head and 'tailroom' at the end so that
381 * they can be later allocated with dp_packet_push_uninit() or
382 * dp_packet_put_uninit() without reallocating the dp_packet. */
384 dp_packet_reserve_with_tailroom(struct dp_packet *b, size_t headroom,
387 ovs_assert(!dp_packet_size(b));
388 dp_packet_prealloc_tailroom(b, headroom + tailroom);
389 dp_packet_set_data(b, (char*)dp_packet_data(b) + headroom);
392 /* Prefixes 'size' bytes to the head end of 'b', reallocating and copying its
393 * data if necessary. Returns a pointer to the first byte of the data's
394 * location in the dp_packet. The new data is left uninitialized. */
396 dp_packet_push_uninit(struct dp_packet *b, size_t size)
398 dp_packet_prealloc_headroom(b, size);
399 dp_packet_set_data(b, (char*)dp_packet_data(b) - size);
400 dp_packet_set_size(b, dp_packet_size(b) + size);
401 return dp_packet_data(b);
404 /* Prefixes 'size' zeroed bytes to the head end of 'b', reallocating and
405 * copying its data if necessary. Returns a pointer to the first byte of the
406 * data's location in the dp_packet. */
408 dp_packet_push_zeros(struct dp_packet *b, size_t size)
410 void *dst = dp_packet_push_uninit(b, size);
411 memset(dst, 0, size);
415 /* Copies the 'size' bytes starting at 'p' to the head end of 'b', reallocating
416 * and copying its data if necessary. Returns a pointer to the first byte of
417 * the data's location in the dp_packet. */
419 dp_packet_push(struct dp_packet *b, const void *p, size_t size)
421 void *dst = dp_packet_push_uninit(b, size);
422 memcpy(dst, p, size);
426 /* Returns the data in 'b' as a block of malloc()'d memory and frees the buffer
427 * within 'b'. (If 'b' itself was dynamically allocated, e.g. with
428 * dp_packet_new(), then it should still be freed with, e.g., dp_packet_delete().) */
430 dp_packet_steal_data(struct dp_packet *b)
433 ovs_assert(b->source != DPBUF_DPDK);
435 if (b->source == DPBUF_MALLOC && dp_packet_data(b) == dp_packet_base(b)) {
436 p = dp_packet_data(b);
438 p = xmemdup(dp_packet_data(b), dp_packet_size(b));
439 if (b->source == DPBUF_MALLOC) {
440 free(dp_packet_base(b));
443 dp_packet_set_base(b, NULL);
444 dp_packet_set_data(b, NULL);
449 dp_packet_adjust_layer_offset(uint16_t *offset, int increment)
451 if (*offset != UINT16_MAX) {
452 *offset += increment;
456 /* Adjust the size of the l2_5 portion of the dp_packet, updating the l2
457 * pointer and the layer offsets. The caller is responsible for
458 * modifying the contents. */
460 dp_packet_resize_l2_5(struct dp_packet *b, int increment)
462 if (increment >= 0) {
463 dp_packet_push_uninit(b, increment);
465 dp_packet_pull(b, -increment);
468 /* Adjust layer offsets after l2_5. */
469 dp_packet_adjust_layer_offset(&b->l3_ofs, increment);
470 dp_packet_adjust_layer_offset(&b->l4_ofs, increment);
472 return dp_packet_data(b);
475 /* Adjust the size of the l2 portion of the dp_packet, updating the l2
476 * pointer and the layer offsets. The caller is responsible for
477 * modifying the contents. */
479 dp_packet_resize_l2(struct dp_packet *b, int increment)
481 dp_packet_resize_l2_5(b, increment);
482 dp_packet_adjust_layer_offset(&b->l2_5_ofs, increment);
483 return dp_packet_data(b);