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);
33 dp_packet_reset_cutlen(b);
37 dp_packet_use__(struct dp_packet *b, void *base, size_t allocated,
38 enum dp_packet_source source)
40 dp_packet_set_base(b, base);
41 dp_packet_set_data(b, base);
42 dp_packet_set_size(b, 0);
44 dp_packet_init__(b, allocated, source);
47 /* Initializes 'b' as an empty dp_packet that contains the 'allocated' bytes of
48 * memory starting at 'base'. 'base' should be the first byte of a region
49 * obtained from malloc(). It will be freed (with free()) if 'b' is resized or
52 dp_packet_use(struct dp_packet *b, void *base, size_t allocated)
54 dp_packet_use__(b, base, allocated, DPBUF_MALLOC);
57 /* Initializes 'b' as an empty dp_packet that contains the 'allocated' bytes of
58 * memory starting at 'base'. 'base' should point to a buffer on the stack.
59 * (Nothing actually relies on 'base' being allocated on the stack. It could
60 * be static or malloc()'d memory. But stack space is the most common use
63 * 'base' should be appropriately aligned. Using an array of uint32_t or
64 * uint64_t for the buffer is a reasonable way to ensure appropriate alignment
65 * for 32- or 64-bit data.
67 * An dp_packet operation that requires reallocating data will copy the provided
68 * buffer into a malloc()'d buffer. Thus, it is wise to call dp_packet_uninit()
69 * on an dp_packet initialized by this function, so that if it expanded into the
70 * heap, that memory is freed. */
72 dp_packet_use_stub(struct dp_packet *b, void *base, size_t allocated)
74 dp_packet_use__(b, base, allocated, DPBUF_STUB);
77 /* Initializes 'b' as an dp_packet whose data starts at 'data' and continues for
78 * 'size' bytes. This is appropriate for an dp_packet that will be used to
79 * inspect existing data, without moving it around or reallocating it, and
80 * generally without modifying it at all.
82 * An dp_packet operation that requires reallocating data will assert-fail if this
83 * function was used to initialize it. */
85 dp_packet_use_const(struct dp_packet *b, const void *data, size_t size)
87 dp_packet_use__(b, CONST_CAST(void *, data), size, DPBUF_STACK);
88 dp_packet_set_size(b, size);
91 /* Initializes 'b' as an empty dp_packet that contains the 'allocated' bytes of
92 * memory starting at 'base'. DPDK allocated dp_packet and *data is allocated
93 * from one continous memory region, so in memory data start right after
94 * dp_packet. Therefore there is special method to free this type of
95 * buffer. dp_packet base, data and size are initialized by dpdk rcv() so no
96 * need to initialize those fields. */
98 dp_packet_init_dpdk(struct dp_packet *b, size_t allocated)
100 dp_packet_init__(b, allocated, DPBUF_DPDK);
103 /* Initializes 'b' as an empty dp_packet with an initial capacity of 'size'
106 dp_packet_init(struct dp_packet *b, size_t size)
108 dp_packet_use(b, size ? xmalloc(size) : NULL, size);
111 /* Frees memory that 'b' points to. */
113 dp_packet_uninit(struct dp_packet *b)
116 if (b->source == DPBUF_MALLOC) {
117 free(dp_packet_base(b));
118 } else if (b->source == DPBUF_DPDK) {
120 /* If this dp_packet was allocated by DPDK it must have been
121 * created as a dp_packet */
122 free_dpdk_buf((struct dp_packet*) b);
128 /* Creates and returns a new dp_packet with an initial capacity of 'size'
131 dp_packet_new(size_t size)
133 struct dp_packet *b = xmalloc(sizeof *b);
134 dp_packet_init(b, size);
138 /* Creates and returns a new dp_packet with an initial capacity of 'size +
139 * headroom' bytes, reserving the first 'headroom' bytes as headroom. */
141 dp_packet_new_with_headroom(size_t size, size_t headroom)
143 struct dp_packet *b = dp_packet_new(size + headroom);
144 dp_packet_reserve(b, headroom);
148 /* Creates and returns a new dp_packet that initially contains a copy of the
149 * 'dp_packet_size(buffer)' bytes of data starting at 'buffer->data' with no headroom or
152 dp_packet_clone(const struct dp_packet *buffer)
154 return dp_packet_clone_with_headroom(buffer, 0);
157 /* Creates and returns a new dp_packet whose data are copied from 'buffer'. The
158 * returned dp_packet will additionally have 'headroom' bytes of headroom. */
160 dp_packet_clone_with_headroom(const struct dp_packet *buffer, size_t headroom)
162 struct dp_packet *new_buffer;
164 new_buffer = dp_packet_clone_data_with_headroom(dp_packet_data(buffer),
165 dp_packet_size(buffer),
167 new_buffer->l2_pad_size = buffer->l2_pad_size;
168 new_buffer->l2_5_ofs = buffer->l2_5_ofs;
169 new_buffer->l3_ofs = buffer->l3_ofs;
170 new_buffer->l4_ofs = buffer->l4_ofs;
171 new_buffer->md = buffer->md;
172 new_buffer->cutlen = buffer->cutlen;
174 new_buffer->mbuf.ol_flags = buffer->mbuf.ol_flags;
176 new_buffer->rss_hash_valid = buffer->rss_hash_valid;
179 if (dp_packet_rss_valid(new_buffer)) {
181 new_buffer->mbuf.hash.rss = buffer->mbuf.hash.rss;
183 new_buffer->rss_hash = buffer->rss_hash;
190 /* Creates and returns a new dp_packet that initially contains a copy of the
191 * 'size' bytes of data starting at 'data' with no headroom or tailroom. */
193 dp_packet_clone_data(const void *data, size_t size)
195 return dp_packet_clone_data_with_headroom(data, size, 0);
198 /* Creates and returns a new dp_packet that initially contains 'headroom' bytes of
199 * headroom followed by a copy of the 'size' bytes of data starting at
202 dp_packet_clone_data_with_headroom(const void *data, size_t size, size_t headroom)
204 struct dp_packet *b = dp_packet_new_with_headroom(size, headroom);
205 dp_packet_put(b, data, size);
210 dp_packet_copy__(struct dp_packet *b, uint8_t *new_base,
211 size_t new_headroom, size_t new_tailroom)
213 const uint8_t *old_base = dp_packet_base(b);
214 size_t old_headroom = dp_packet_headroom(b);
215 size_t old_tailroom = dp_packet_tailroom(b);
216 size_t copy_headroom = MIN(old_headroom, new_headroom);
217 size_t copy_tailroom = MIN(old_tailroom, new_tailroom);
219 memcpy(&new_base[new_headroom - copy_headroom],
220 &old_base[old_headroom - copy_headroom],
221 copy_headroom + dp_packet_size(b) + copy_tailroom);
224 /* Reallocates 'b' so that it has exactly 'new_headroom' and 'new_tailroom'
225 * bytes of headroom and tailroom, respectively. */
227 dp_packet_resize__(struct dp_packet *b, size_t new_headroom, size_t new_tailroom)
229 void *new_base, *new_data;
230 size_t new_allocated;
232 new_allocated = new_headroom + dp_packet_size(b) + new_tailroom;
239 if (new_headroom == dp_packet_headroom(b)) {
240 new_base = xrealloc(dp_packet_base(b), new_allocated);
242 new_base = xmalloc(new_allocated);
243 dp_packet_copy__(b, new_base, new_headroom, new_tailroom);
244 free(dp_packet_base(b));
252 b->source = DPBUF_MALLOC;
253 new_base = xmalloc(new_allocated);
254 dp_packet_copy__(b, new_base, new_headroom, new_tailroom);
261 dp_packet_set_allocated(b, new_allocated);
262 dp_packet_set_base(b, new_base);
264 new_data = (char *) new_base + new_headroom;
265 if (dp_packet_data(b) != new_data) {
266 dp_packet_set_data(b, new_data);
270 /* Ensures that 'b' has room for at least 'size' bytes at its tail end,
271 * reallocating and copying its data if necessary. Its headroom, if any, is
274 dp_packet_prealloc_tailroom(struct dp_packet *b, size_t size)
276 if (size > dp_packet_tailroom(b)) {
277 dp_packet_resize__(b, dp_packet_headroom(b), MAX(size, 64));
281 /* Ensures that 'b' has room for at least 'size' bytes at its head,
282 * reallocating and copying its data if necessary. Its tailroom, if any, is
285 dp_packet_prealloc_headroom(struct dp_packet *b, size_t size)
287 if (size > dp_packet_headroom(b)) {
288 dp_packet_resize__(b, MAX(size, 64), dp_packet_tailroom(b));
292 /* Shifts all of the data within the allocated space in 'b' by 'delta' bytes.
293 * For example, a 'delta' of 1 would cause each byte of data to move one byte
294 * forward (from address 'p' to 'p+1'), and a 'delta' of -1 would cause each
295 * byte to move one byte backward (from 'p' to 'p-1'). */
297 dp_packet_shift(struct dp_packet *b, int delta)
299 ovs_assert(delta > 0 ? delta <= dp_packet_tailroom(b)
300 : delta < 0 ? -delta <= dp_packet_headroom(b)
304 char *dst = (char *) dp_packet_data(b) + delta;
305 memmove(dst, dp_packet_data(b), dp_packet_size(b));
306 dp_packet_set_data(b, dst);
310 /* Appends 'size' bytes of data to the tail end of 'b', reallocating and
311 * copying its data if necessary. Returns a pointer to the first byte of the
312 * new data, which is left uninitialized. */
314 dp_packet_put_uninit(struct dp_packet *b, size_t size)
317 dp_packet_prealloc_tailroom(b, size);
318 p = dp_packet_tail(b);
319 dp_packet_set_size(b, dp_packet_size(b) + size);
323 /* Appends 'size' zeroed bytes to the tail end of 'b'. Data in 'b' is
324 * reallocated and copied if necessary. Returns a pointer to the first byte of
325 * the data's location in the dp_packet. */
327 dp_packet_put_zeros(struct dp_packet *b, size_t size)
329 void *dst = dp_packet_put_uninit(b, size);
330 memset(dst, 0, size);
334 /* Appends the 'size' bytes of data in 'p' to the tail end of 'b'. Data in 'b'
335 * is reallocated and copied if necessary. Returns a pointer to the first
336 * byte of the data's location in the dp_packet. */
338 dp_packet_put(struct dp_packet *b, const void *p, size_t size)
340 void *dst = dp_packet_put_uninit(b, size);
341 memcpy(dst, p, size);
345 /* Parses as many pairs of hex digits as possible (possibly separated by
346 * spaces) from the beginning of 's', appending bytes for their values to 'b'.
347 * Returns the first character of 's' that is not the first of a pair of hex
348 * digits. If 'n' is nonnull, stores the number of bytes added to 'b' in
351 dp_packet_put_hex(struct dp_packet *b, const char *s, size_t *n)
353 size_t initial_size = dp_packet_size(b);
358 s += strspn(s, " \t\r\n");
359 byte = hexits_value(s, 2, &ok);
362 *n = dp_packet_size(b) - initial_size;
364 return CONST_CAST(char *, s);
367 dp_packet_put(b, &byte, 1);
372 /* Reserves 'size' bytes of headroom so that they can be later allocated with
373 * dp_packet_push_uninit() without reallocating the dp_packet. */
375 dp_packet_reserve(struct dp_packet *b, size_t size)
377 ovs_assert(!dp_packet_size(b));
378 dp_packet_prealloc_tailroom(b, size);
379 dp_packet_set_data(b, (char*)dp_packet_data(b) + size);
382 /* Reserves 'headroom' bytes at the head and 'tailroom' at the end so that
383 * they can be later allocated with dp_packet_push_uninit() or
384 * dp_packet_put_uninit() without reallocating the dp_packet. */
386 dp_packet_reserve_with_tailroom(struct dp_packet *b, size_t headroom,
389 ovs_assert(!dp_packet_size(b));
390 dp_packet_prealloc_tailroom(b, headroom + tailroom);
391 dp_packet_set_data(b, (char*)dp_packet_data(b) + headroom);
394 /* Prefixes 'size' bytes to the head end of 'b', reallocating and copying its
395 * data if necessary. Returns a pointer to the first byte of the data's
396 * location in the dp_packet. The new data is left uninitialized. */
398 dp_packet_push_uninit(struct dp_packet *b, size_t size)
400 dp_packet_prealloc_headroom(b, size);
401 dp_packet_set_data(b, (char*)dp_packet_data(b) - size);
402 dp_packet_set_size(b, dp_packet_size(b) + size);
403 return dp_packet_data(b);
406 /* Prefixes 'size' zeroed bytes to the head end of 'b', reallocating and
407 * copying its data if necessary. Returns a pointer to the first byte of the
408 * data's location in the dp_packet. */
410 dp_packet_push_zeros(struct dp_packet *b, size_t size)
412 void *dst = dp_packet_push_uninit(b, size);
413 memset(dst, 0, size);
417 /* Copies the 'size' bytes starting at 'p' to the head end of 'b', reallocating
418 * and copying its data if necessary. Returns a pointer to the first byte of
419 * the data's location in the dp_packet. */
421 dp_packet_push(struct dp_packet *b, const void *p, size_t size)
423 void *dst = dp_packet_push_uninit(b, size);
424 memcpy(dst, p, size);
428 /* Returns the data in 'b' as a block of malloc()'d memory and frees the buffer
429 * within 'b'. (If 'b' itself was dynamically allocated, e.g. with
430 * dp_packet_new(), then it should still be freed with, e.g., dp_packet_delete().) */
432 dp_packet_steal_data(struct dp_packet *b)
435 ovs_assert(b->source != DPBUF_DPDK);
437 if (b->source == DPBUF_MALLOC && dp_packet_data(b) == dp_packet_base(b)) {
438 p = dp_packet_data(b);
440 p = xmemdup(dp_packet_data(b), dp_packet_size(b));
441 if (b->source == DPBUF_MALLOC) {
442 free(dp_packet_base(b));
445 dp_packet_set_base(b, NULL);
446 dp_packet_set_data(b, NULL);
451 dp_packet_adjust_layer_offset(uint16_t *offset, int increment)
453 if (*offset != UINT16_MAX) {
454 *offset += increment;
458 /* Adjust the size of the l2_5 portion of the dp_packet, updating the l2
459 * pointer and the layer offsets. The caller is responsible for
460 * modifying the contents. */
462 dp_packet_resize_l2_5(struct dp_packet *b, int increment)
464 if (increment >= 0) {
465 dp_packet_push_uninit(b, increment);
467 dp_packet_pull(b, -increment);
470 /* Adjust layer offsets after l2_5. */
471 dp_packet_adjust_layer_offset(&b->l3_ofs, increment);
472 dp_packet_adjust_layer_offset(&b->l4_ofs, increment);
474 return dp_packet_data(b);
477 /* Adjust the size of the l2 portion of the dp_packet, updating the l2
478 * pointer and the layer offsets. The caller is responsible for
479 * modifying the contents. */
481 dp_packet_resize_l2(struct dp_packet *b, int increment)
483 dp_packet_resize_l2_5(b, increment);
484 dp_packet_adjust_layer_offset(&b->l2_5_ofs, increment);
485 return dp_packet_data(b);