1 /*-
2 * Copyright (c) 1982, 1986, 1988, 1993
3 * The Regents of the University of California.
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of the University nor the names of its contributors
15 * may be used to endorse or promote products derived from this software
16 * without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 *
30 */
31
32 #ifndef _USER_MBUF_H_
33 #define _USER_MBUF_H_
34
35 /* __Userspace__ header file for mbufs */
36 #include <stdio.h>
37 #if !defined(SCTP_SIMPLE_ALLOCATOR)
38 #include "umem.h"
39 #endif
40 #include "user_malloc.h"
41 #include "netinet/sctp_os_userspace.h"
42
43 #define USING_MBUF_CONSTRUCTOR 0
44
45 /* For Linux */
46 #ifndef MSIZE
47 #define MSIZE 256
48 /* #define MSIZE 1024 */
49 #endif
50 #ifndef MCLBYTES
51 #define MCLBYTES 2048
52 #endif
53
54 struct mbuf * m_gethdr(int how, short type);
55 struct mbuf * m_get(int how, short type);
56 struct mbuf * m_free(struct mbuf *m);
57 void m_clget(struct mbuf *m, int how);
58 struct mbuf * m_getm2(struct mbuf *m, int len, int how, short type, int flags, int allonebuf);
59 struct mbuf *m_uiotombuf(struct uio *uio, int how, int len, int align, int flags);
60 u_int m_length(struct mbuf *m0, struct mbuf **last);
61 struct mbuf *m_last(struct mbuf *m);
62
63 /* mbuf initialization function */
64 void mbuf_initialize(void *);
65
66 #define M_MOVE_PKTHDR(to, from) m_move_pkthdr((to), (from))
67 #define MGET(m, how, type) ((m) = m_get((how), (type)))
68 #define MGETHDR(m, how, type) ((m) = m_gethdr((how), (type)))
69 #define MCLGET(m, how) m_clget((m), (how))
70
71
72 #define M_HDR_PAD ((sizeof(intptr_t)==4) ? 2 : 6) /* modified for __Userspace__ */
73
74 /* Length to m_copy to copy all. */
75 #define M_COPYALL 1000000000
76
77 /* umem_cache_t is defined in user_include/umem.h as
78 * typedef struct umem_cache umem_cache_t;
79 * Note:umem_zone_t is a pointer.
mbuf_constructor_dup(struct mbuf * m,int pkthdr,short type)80 */
81 #if defined(SCTP_SIMPLE_ALLOCATOR)
82 typedef size_t sctp_zone_t;
83 #else
84 typedef umem_cache_t *sctp_zone_t;
85 #endif
86
87 extern sctp_zone_t zone_mbuf;
88 extern sctp_zone_t zone_clust;
89 extern sctp_zone_t zone_ext_refcnt;
90
91 /*-
92 * Macros for type conversion:
93 * mtod(m, t) -- Convert mbuf pointer to data pointer of correct type.
94 * dtom(x) -- Convert data pointer within mbuf to mbuf pointer (XXX).
95 */
96 #define mtod(m, t) ((t)((m)->m_data))
97 #define dtom(x) ((struct mbuf *)((intptr_t)(x) & ~(MSIZE-1)))
98
99 struct mb_args {
100 int flags; /* Flags for mbuf being allocated */
101 short type; /* Type of mbuf being allocated */
102 };
103
104 struct clust_args {
105 struct mbuf * parent_mbuf;
106 };
107
108 struct mbuf * m_split(struct mbuf *, int, int);
m_get(int how,short type)109 void m_cat(struct mbuf *m, struct mbuf *n);
110 void m_adj(struct mbuf *, int);
111 void mb_free_ext(struct mbuf *);
112 void m_freem(struct mbuf *);
113 struct m_tag *m_tag_alloc(uint32_t, int, int, int);
114 struct mbuf *m_copym(struct mbuf *, int, int, int);
115 void m_copyback(struct mbuf *, int, int, caddr_t);
116 struct mbuf *m_pullup(struct mbuf *, int);
117 struct mbuf *m_pulldown(struct mbuf *, int off, int len, int *offp);
118 int m_dup_pkthdr(struct mbuf *, struct mbuf *, int);
119 struct m_tag *m_tag_copy(struct m_tag *, int);
120 int m_tag_copy_chain(struct mbuf *, struct mbuf *, int);
121 struct mbuf *m_prepend(struct mbuf *, int, int);
122 void m_copydata(const struct mbuf *, int, int, caddr_t);
123
124 #define MBUF_MEM_NAME "mbuf"
125 #define MBUF_CLUSTER_MEM_NAME "mbuf_cluster"
126 #define MBUF_EXTREFCNT_MEM_NAME "mbuf_ext_refcnt"
127
128 #define MT_NOINIT 255 /* Not a type but a flag to allocate
129 a non-initialized mbuf */
130
131 /*
132 * Mbufs are of a single size, MSIZE (sys/param.h), which includes overhead.
133 * An mbuf may add a single "mbuf cluster" of size MCLBYTES (also in
134 * sys/param.h), which has no additional overhead and is used instead of the
135 * internal data area; this is done when at least MINCLSIZE of data must be
136 * stored. Additionally, it is possible to allocate a separate buffer
137 * externally and attach it to the mbuf in a way similar to that of mbuf
138 * clusters.
139 */
140 #define MLEN ((int)(MSIZE - sizeof(struct m_hdr))) /* normal data len */
141 #define MHLEN ((int)(MLEN - sizeof(struct pkthdr))) /* data len w/pkthdr */
142 #define MINCLSIZE ((int)(MHLEN + 1)) /* smallest amount to put in cluster */
143 #define M_MAXCOMPRESS (MHLEN / 2) /* max amount to copy for compression */
144
145
146 /*
147 * Header present at the beginning of every mbuf.
148 */
149 struct m_hdr {
150 struct mbuf *mh_next; /* next buffer in chain */
m_gethdr(int how,short type)151 struct mbuf *mh_nextpkt; /* next chain in queue/record */
152 caddr_t mh_data; /* location of data */
153 int mh_len; /* amount of data in this mbuf */
154 int mh_flags; /* flags; see below */
155 short mh_type; /* type of data in this mbuf */
156 uint8_t pad[M_HDR_PAD];/* word align */
157 };
158
159 /*
160 * Packet tag structure (see below for details).
161 */
162 struct m_tag {
163 SLIST_ENTRY(m_tag) m_tag_link; /* List of packet tags */
164 uint16_t m_tag_id; /* Tag ID */
165 uint16_t m_tag_len; /* Length of data */
166 uint32_t m_tag_cookie; /* ABI/Module ID */
167 void (*m_tag_free)(struct m_tag *);
168 };
169
170 /*
171 * Record/packet header in first mbuf of chain; valid only if M_PKTHDR is set.
172 */
173 struct pkthdr {
174 struct ifnet *rcvif; /* rcv interface */
175 /* variables for ip and tcp reassembly */
176 void *header; /* pointer to packet header */
177 int len; /* total packet length */
178 /* variables for hardware checksum */
179 int csum_flags; /* flags regarding checksum */
180 int csum_data; /* data field used by csum routines */
181 uint16_t tso_segsz; /* TSO segment size */
182 uint16_t ether_vtag; /* Ethernet 802.1p+q vlan tag */
183 SLIST_HEAD(packet_tags, m_tag) tags; /* list of packet tags */
184 };
185
186 /*
187 * Description of external storage mapped into mbuf; valid only if M_EXT is
m_free(struct mbuf * m)188 * set.
189 */
190 struct m_ext {
191 caddr_t ext_buf; /* start of buffer */
192 void (*ext_free) /* free routine if not the usual */
193 (void *, void *);
194 void *ext_args; /* optional argument pointer */
195 u_int ext_size; /* size of buffer, for ext_free */
196 volatile u_int *ref_cnt; /* pointer to ref count info */
197 int ext_type; /* type of external storage */
198 };
199
200
201 /*
202 * The core of the mbuf object along with some shortcut defined for practical
203 * purposes.
204 */
205 struct mbuf {
206 struct m_hdr m_hdr;
clust_constructor_dup(caddr_t m_clust,struct mbuf * m)207 union {
208 struct {
209 struct pkthdr MH_pkthdr; /* M_PKTHDR set */
210 union {
211 struct m_ext MH_ext; /* M_EXT set */
212 char MH_databuf[MHLEN];
213 } MH_dat;
214 } MH;
215 char M_databuf[MLEN]; /* !M_PKTHDR, !M_EXT */
216 } M_dat;
217 };
218
219 #define m_next m_hdr.mh_next
220 #define m_len m_hdr.mh_len
221 #define m_data m_hdr.mh_data
222 #define m_type m_hdr.mh_type
223 #define m_flags m_hdr.mh_flags
224 #define m_nextpkt m_hdr.mh_nextpkt
225 #define m_act m_nextpkt
226 #define m_pkthdr M_dat.MH.MH_pkthdr
227 #define m_ext M_dat.MH.MH_dat.MH_ext
228 #define m_pktdat M_dat.MH.MH_dat.MH_databuf
229 #define m_dat M_dat.M_databuf
230
231
232 /*
233 * mbuf flags.
234 */
235 #define M_EXT 0x0001 /* has associated external storage */
236 #define M_PKTHDR 0x0002 /* start of record */
237 #define M_EOR 0x0004 /* end of record */
238 #define M_RDONLY 0x0008 /* associated data is marked read-only */
239 #define M_PROTO1 0x0010 /* protocol-specific */
240 #define M_PROTO2 0x0020 /* protocol-specific */
241 #define M_PROTO3 0x0040 /* protocol-specific */
242 #define M_PROTO4 0x0080 /* protocol-specific */
m_clget(struct mbuf * m,int how)243 #define M_PROTO5 0x0100 /* protocol-specific */
244 #define M_FREELIST 0x8000 /* mbuf is on the free list */
245
246
247 /*
248 * Flags copied when copying m_pkthdr.
249 */
250 #define M_COPYFLAGS (M_PKTHDR|M_EOR|M_RDONLY|M_PROTO1|M_PROTO1|M_PROTO2|\
251 M_PROTO3|M_PROTO4|M_PROTO5|\
252 M_BCAST|M_MCAST|M_FRAG|M_FIRSTFRAG|M_LASTFRAG|\
253 M_VLANTAG|M_PROMISC)
254
255
256 /*
257 * mbuf pkthdr flags (also stored in m_flags).
258 */
259 #define M_BCAST 0x0200 /* send/received as link-level broadcast */
260 #define M_MCAST 0x0400 /* send/received as link-level multicast */
261 #define M_FRAG 0x0800 /* packet is a fragment of a larger packet */
262 #define M_FIRSTFRAG 0x1000 /* packet is first fragment */
263 #define M_LASTFRAG 0x2000 /* packet is last fragment */
264 #define M_VLANTAG 0x10000 /* ether_vtag is valid */
265 #define M_PROMISC 0x20000 /* packet was not for us */
266 #define M_NOFREE 0x40000 /* do not free mbuf - it is embedded in the cluster */
267
268
269 /*
270 * External buffer types: identify ext_buf type.
271 */
272 #define EXT_CLUSTER 1 /* mbuf cluster */
273 #define EXT_SFBUF 2 /* sendfile(2)'s sf_bufs */
274 #define EXT_JUMBOP 3 /* jumbo cluster 4096 bytes */
275 #define EXT_JUMBO9 4 /* jumbo cluster 9216 bytes */
276 #define EXT_JUMBO16 5 /* jumbo cluster 16184 bytes */
277 #define EXT_PACKET 6 /* mbuf+cluster from packet zone */
278 #define EXT_MBUF 7 /* external mbuf reference (M_IOVEC) */
279 #define EXT_NET_DRV 100 /* custom ext_buf provided by net driver(s) */
280 #define EXT_MOD_TYPE 200 /* custom module's ext_buf type */
281 #define EXT_DISPOSABLE 300 /* can throw this buffer away w/page flipping */
282 #define EXT_EXTREF 400 /* has externally maintained ref_cnt ptr */
283
284
285 /*
286 * mbuf types.
287 */
288 #define MT_NOTMBUF 0 /* USED INTERNALLY ONLY! Object is not mbuf */
289 #define MT_DATA 1 /* dynamic (data) allocation */
290 #define MT_HEADER MT_DATA /* packet header, use M_PKTHDR instead */
291 #define MT_SONAME 8 /* socket name */
292 #define MT_CONTROL 14 /* extra-data protocol message */
293 #define MT_OOBDATA 15 /* expedited data */
294 #define MT_NTYPES 16 /* number of mbuf types for mbtypes[] */
295
296 #define MT_NOINIT 255 /* Not a type but a flag to allocate
297 a non-initialized mbuf */
298
299 /*
300 * __Userspace__ flags like M_NOWAIT are defined in malloc.h
301 * Flags like these are used in functions like uma_zalloc()
302 * but don't have an equivalent in userland umem
303 * Flags specifying how an allocation should be made.
304 *
305 * The flag to use is as follows:
306 * - M_DONTWAIT or M_NOWAIT from an interrupt handler to not block allocation.
307 * - M_WAIT or M_WAITOK or M_TRYWAIT from wherever it is safe to block.
308 *
309 * M_DONTWAIT/M_NOWAIT means that we will not block the thread explicitly and
310 * if we cannot allocate immediately we may return NULL, whereas
311 * M_WAIT/M_WAITOK/M_TRYWAIT means that if we cannot allocate resources we
312 * will block until they are available, and thus never return NULL.
313 *
314 * XXX Eventually just phase this out to use M_WAITOK/M_NOWAIT.
315 */
316 #define MBTOM(how) (how)
317
318 void m_tag_delete(struct mbuf *, struct m_tag *);
319 void m_tag_delete_chain(struct mbuf *, struct m_tag *);
320 void m_move_pkthdr(struct mbuf *, struct mbuf *);
321 void m_tag_free_default(struct m_tag *);
322
323 extern int max_linkhdr; /* Largest link-level header */
324 extern int max_protohdr; /* Size of largest protocol layer header. See user_mbuf.c */
325
326 /*
327 * Evaluate TRUE if it's safe to write to the mbuf m's data region (this can
328 * be both the local data payload, or an external buffer area, depending on
329 * whether M_EXT is set).
330 */
331 #define M_WRITABLE(m) (!((m)->m_flags & M_RDONLY) && \
332 (!(((m)->m_flags & M_EXT)) || \
333 (*((m)->m_ext.ref_cnt) == 1)) ) \
334
335
336 /*
337 * Compute the amount of space available before the current start of data in
338 * an mbuf.
339 *
340 * The M_WRITABLE() is a temporary, conservative safety measure: the burden
341 * of checking writability of the mbuf data area rests solely with the caller.
342 */
343 #define M_LEADINGSPACE(m) \
344 (((m)->m_flags & M_EXT) ? \
345 (M_WRITABLE(m) ? (m)->m_data - (m)->m_ext.ext_buf : 0): \
346 ((m)->m_flags & M_PKTHDR)? (m)->m_data - (m)->m_pktdat : \
347 (m)->m_data - (m)->m_dat)
348
349 /*
350 * Compute the amount of space available after the end of data in an mbuf.
351 *
352 * The M_WRITABLE() is a temporary, conservative safety measure: the burden
353 * of checking writability of the mbuf data area rests solely with the caller.
354 */
355 #define M_TRAILINGSPACE(m) \
356 (((m)->m_flags & M_EXT) ? \
357 (M_WRITABLE(m) ? (m)->m_ext.ext_buf + (m)->m_ext.ext_size \
358 - ((m)->m_data + (m)->m_len) : 0) : \
359 &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len))
360
361
362
363 /*
364 * Arrange to prepend space of size plen to mbuf m. If a new mbuf must be
365 * allocated, how specifies whether to wait. If the allocation fails, the
366 * original mbuf chain is freed and m is set to NULL.
367 */
368 #define M_PREPEND(m, plen, how) do { \
369 struct mbuf **_mmp = &(m); \
370 struct mbuf *_mm = *_mmp; \
371 int _mplen = (plen); \
372 int __mhow = (how); \
m_uiotombuf(struct uio * uio,int how,int len,int align,int flags)373 \
374 if (M_LEADINGSPACE(_mm) >= _mplen) { \
375 _mm->m_data -= _mplen; \
376 _mm->m_len += _mplen; \
377 } else \
378 _mm = m_prepend(_mm, _mplen, __mhow); \
379 if (_mm != NULL && _mm->m_flags & M_PKTHDR) \
380 _mm->m_pkthdr.len += _mplen; \
381 *_mmp = _mm; \
382 } while (0)
383
384 /*
385 * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place an
386 * object of the specified size at the end of the mbuf, longword aligned.
387 */
388 #define M_ALIGN(m, len) do { \
389 KASSERT(!((m)->m_flags & (M_PKTHDR|M_EXT)), \
390 ("%s: M_ALIGN not normal mbuf", __func__)); \
391 KASSERT((m)->m_data == (m)->m_dat, \
392 ("%s: M_ALIGN not a virgin mbuf", __func__)); \
393 (m)->m_data += (MLEN - (len)) & ~(sizeof(long) - 1); \
394 } while (0)
395
396 /*
397 * As above, for mbufs allocated with m_gethdr/MGETHDR or initialized by
398 * M_DUP/MOVE_PKTHDR.
399 */
400 #define MH_ALIGN(m, len) do { \
401 KASSERT((m)->m_flags & M_PKTHDR && !((m)->m_flags & M_EXT), \
402 ("%s: MH_ALIGN not PKTHDR mbuf", __func__)); \
403 KASSERT((m)->m_data == (m)->m_pktdat, \
404 ("%s: MH_ALIGN not a virgin mbuf", __func__)); \
405 (m)->m_data += (MHLEN - (len)) & ~(sizeof(long) - 1); \
406 } while (0)
407
408 #define M_SIZE(m) \
409 (((m)->m_flags & M_EXT) ? (m)->m_ext.ext_size : \
410 ((m)->m_flags & M_PKTHDR) ? MHLEN : \
411 MLEN)
412
413 #endif
414