xref: /illumos-gate/usr/src/uts/common/smbsrv/mbuf.h (revision 897907ce)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2019 Joyent, Inc.
23  * Copyright 2011-2021 Tintri by DDN, Inc. All rights reserved.
24  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
25  * Use is subject to license terms.
26  */
27 /*
28  * Copyright (c) 1982, 1986, 1988 Regents of the University of California.
29  * All rights reserved.
30  *
31  * Redistribution and use in source and binary forms, with or without
32  * modification, are permitted provided that the following conditions
33  * are met:
34  * 1. Redistributions of source code must retain the above copyright
35  *    notice, this list of conditions and the following disclaimer.
36  * 2. Redistributions in binary form must reproduce the above copyright
37  *    notice, this list of conditions and the following disclaimer in the
38  *    documentation and/or other materials provided with the distribution.
39  * 3. All advertising materials mentioning features or use of this software
40  *    must display the following acknowledgement:
41  *	This product includes software developed by the University of
42  *	California, Berkeley and its contributors.
43  * 4. Neither the name of the University nor the names of its contributors
44  *    may be used to endorse or promote products derived from this software
45  *    without specific prior written permission.
46  *
47  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
48  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
49  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
50  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
51  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
52  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
53  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
54  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
55  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
56  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
57  * SUCH DAMAGE.
58  *
59  */
60 
61 #ifndef _SMBSRV_MBUF_H
62 #define	_SMBSRV_MBUF_H
63 
64 /*
65  * This mbuf simulation should be replaced with (native) mblk_t support.
66  */
67 
68 #include <sys/types.h>
69 #include <sys/param.h>
70 #include <sys/kmem.h>
71 #include <smbsrv/string.h>
72 
73 #ifdef __cplusplus
74 extern "C" {
75 #endif
76 
77 #define	MSIZE		256
78 #define	MCLBYTES	8192
79 
80 /*
81  * Mbufs are of a single size, MSIZE (machine/machparam.h), which
82  * includes overhead.  An mbuf may add a single "mbuf cluster" of size
83  * MCLBYTES (also in machine/machparam.h), which has no additional overhead
84  * and is used instead of the internal data area; this is done when
85  * at least MINCLSIZE of data must be stored.
86  */
87 
88 #define	MLEN		(MSIZE - sizeof (struct m_hdr))	/* normal data len */
89 #define	MHLEN		(MLEN - sizeof (struct pkthdr))	/* data len w/pkthdr */
90 
91 #define	MINCLSIZE	(MHLEN + MLEN)	/* smallest amount to put in cluster */
92 
93 /*
94  * How much prepend space to put in the first mbuf of a chain.
95  * In SMB we only prepend a 4-byte NBT header, but let's keep the
96  * data part aligned the same as M_ALIGN() does below (8-byte)
97  */
98 #define	MH_PREPEND_SPACE	8
99 
100 /*
101  * Macros for type conversion
102  * mtod(m,t) -	convert mbuf pointer to data pointer of correct type
103  */
104 #define	mtod(m, t)	((t)((m)->m_data))
105 
106 struct mbuf;
107 typedef	void m_ext_free_t(struct mbuf *);
108 
109 /* header at beginning of each mbuf: */
110 struct m_hdr {
111 	struct	mbuf *mh_next;		/* next buffer in chain */
112 	struct	mbuf *mh_nextpkt;	/* next chain in queue/record */
113 	int	mh_len;			/* amount of data in this mbuf */
114 	caddr_t	mh_data;		/* location of data */
115 	short	mh_type;		/* type of data in this mbuf */
116 	short	mh_flags;		/* flags; see below */
117 };
118 
119 /* record/packet header in first mbuf of chain; valid if M_PKTHDR set */
120 struct	pkthdr {
121 	int	len;		/* total packet length */
122 };
123 
124 
125 /* description of external storage mapped into mbuf, valid if M_EXT set */
126 struct m_ext {
127 	caddr_t		ext_buf;	/* start of external buffer */
128 	uint_t		ext_size;	/* size of external buffer */
129 	m_ext_free_t	*ext_free;	/* free function */
130 	void		*ext_arg1;	/* free func arg */
131 };
132 
133 typedef struct mbuf {
134 	struct	m_hdr m_hdr;
135 	union {
136 		struct {
137 			struct	pkthdr MH_pkthdr;	/* M_PKTHDR set */
138 			union {
139 				struct	m_ext MH_ext;	/* M_EXT set */
140 				char	MH_databuf[MHLEN];
141 			} MH_dat;
142 		} MH;
143 		char	M_databuf[MLEN];		/* !M_PKTHDR, !M_EXT */
144 	} M_dat;
145 } mbuf_t;
146 
147 #define	m_next		m_hdr.mh_next
148 #define	m_len		m_hdr.mh_len
149 #define	m_data		m_hdr.mh_data
150 #define	m_type		m_hdr.mh_type
151 #define	m_flags		m_hdr.mh_flags
152 #define	m_nextpkt	m_hdr.mh_nextpkt
153 #define	m_act		m_nextpkt
154 #define	m_pkthdr	M_dat.MH.MH_pkthdr
155 #define	m_ext		M_dat.MH.MH_dat.MH_ext
156 #define	m_pktdat	M_dat.MH.MH_dat.MH_databuf
157 #define	m_dat		M_dat.M_databuf
158 
159 /* mbuf flags */
160 #define	M_EXT		0x0001	/* has associated external storage */
161 #define	M_PKTHDR	0x0002	/* start of record */
162 #define	M_EOR		0x0004	/* end of record */
163 
164 /* mbuf pkthdr flags, also in m_flags */
165 #define	M_BCAST		0x0100	/* send/received as link-level broadcast */
166 #define	M_MCAST		0x0200	/* send/received as link-level multicast */
167 
168 /* flags copied when copying m_pkthdr */
169 #define	M_COPYFLAGS	(M_PKTHDR|M_EOR|M_BCAST|M_MCAST)
170 
171 /* XXX probably only need MT_DATA */
172 
173 /* mbuf types */
174 #define	MT_FREE		0	/* should be on free list */
175 #define	MT_DATA		1	/* dynamic (data) allocation */
176 #define	MT_HEADER	2	/* packet header */
177 #define	MT_SOCKET	3	/* socket structure */
178 #define	MT_PCB		4	/* protocol control block */
179 #define	MT_RTABLE	5	/* routing tables */
180 #define	MT_HTABLE	6	/* IMP host tables */
181 #define	MT_ATABLE	7	/* address resolution tables */
182 #define	MT_SONAME	8	/* socket name */
183 #define	MT_SOOPTS	10	/* socket options */
184 #define	MT_FTABLE	11	/* fragment reassembly header */
185 #define	MT_RIGHTS	12	/* access rights */
186 #define	MT_IFADDR	13	/* interface address */
187 #define	MT_CONTROL	14	/* extra-data protocol message */
188 #define	MT_OOBDATA	15	/* expedited data  */
189 
190 /*
191  * flags to malloc: PBSHORTCUT
192  */
193 #define	M_WAITOK	0x0000
194 #define	M_NOWAIT	0x0001
195 
196 /* flags to m_get/MGET */
197 #define	M_DONTWAIT	M_NOWAIT
198 #define	M_WAIT		M_WAITOK
199 
200 /* BEGIN CSTYLED */
201 
202 /*
203  * mbuf allocation/deallocation macros:
204  *
205  *	MGET(struct mbuf *m, int how, int type)
206  * allocates an mbuf and initializes it to contain internal data.
207  *
208  *	MGETHDR(struct mbuf *m, int how, int type)
209  * allocates an mbuf and initializes it to contain a packet header
210  * and internal data.
211  */
212 
213 #define	MGET(m, how, type) { \
214 	m = smb_mbuf_alloc(); \
215 	(m)->m_next = (struct mbuf *)NULL; \
216 	(m)->m_nextpkt = (struct mbuf *)NULL; \
217 	(m)->m_data = (m)->m_dat; \
218 	(m)->m_flags = 0; \
219 	(m)->m_type = (short)(type); \
220 }
221 
222 #define	MGETHDR(m, how, type) { \
223 	m = smb_mbuf_alloc(); \
224 	(m)->m_type = (MT_HEADER); \
225 	(m)->m_next = (struct mbuf *)NULL; \
226 	(m)->m_nextpkt = (struct mbuf *)NULL; \
227 	(m)->m_data = (m)->m_pktdat; \
228 	(m)->m_flags = M_PKTHDR; \
229 }
230 
231 #define	MCLGET(m, how) \
232 	{ \
233 		(m)->m_ext.ext_buf = smb_mbufcl_alloc();	\
234 		(m)->m_data = (m)->m_ext.ext_buf;		\
235 		(m)->m_flags |= M_EXT;				\
236 		(m)->m_ext.ext_size = MCLBYTES;			\
237 		(m)->m_ext.ext_free = smb_mbufcl_free;		\
238 	}
239 
240 /*
241  * MFREE(struct mbuf *m, struct mbuf *nn)
242  * Free a single mbuf and associated external storage.
243  * Place the successor, if any, in nn.
244  */
245 #define	MFREE(m, nn) \
246 	{ \
247 		if ((m)->m_flags & M_EXT) {			\
248 			(m)->m_ext.ext_free(m);			\
249 			(m)->m_ext.ext_buf = NULL;		\
250 		}						\
251 		(nn) = (m)->m_next;				\
252 		(m)->m_next = 0;				\
253 		smb_mbuf_free(m);				\
254 	}
255 
256 /*
257  * Set the m_data pointer of a newly allocated mbuf to place an object of the
258  * specified size at the end of the mbuf, longword aligned.
259  */
260 #define	M_ALIGN(m, len) \
261 	{ (m)->m_data += (MLEN - (len)) &~ (sizeof (int64_t) - 1); }
262 
263 /*
264  * As above, for mbufs allocated with m_gethdr/MGETHDR
265  * or initialized by M_COPY_PKTHDR.
266  */
267 #define	MH_ALIGN(m, len) \
268 	{ (m)->m_data += (MHLEN - (len)) &~ (sizeof (int64_t) - 1); }
269 
270 /*
271  * Return the address of the start of the buffer associated with an mbuf,
272  * handling external storage, packet-header mbufs, and regular data mbufs.
273  * BSD calls this M_START but that conflicts with stream.h (sigh)
274  */
275 #define	MB_START(m)							\
276 	(((m)->m_flags & M_EXT) ? (m)->m_ext.ext_buf :			\
277 	 ((m)->m_flags & M_PKTHDR) ? &(m)->m_pktdat[0] :		\
278 	 &(m)->m_dat[0])
279 
280 /*
281  * Return the size of the buffer associated with an mbuf, handling external
282  * storage, packet-header mbufs, and regular data mbufs.
283  */
284 #define	M_SIZE(m)							\
285 	(((m)->m_flags & M_EXT) ? (m)->m_ext.ext_size :			\
286 	 ((m)->m_flags & M_PKTHDR) ? MHLEN : MLEN)
287 
288 /*
289  * Compute the amount of space available before the current start of data in
290  * an mbuf.
291  */
292 #define	M_LEADINGSPACE(m)	((m)->m_data - MB_START(m))
293 
294 /*
295  * Compute the amount of space available after the end of data in an mbuf.
296  */
297 #define	M_TRAILINGSPACE(m)						\
298 	((MB_START(m) + M_SIZE(m)) - ((m)->m_data + (m)->m_len))
299 
300 /* END CSTYLED */
301 
302 #define	SMB_MBC_MAGIC		0x4D42435F
303 #define	SMB_MBC_VALID(p)	ASSERT((p)->mbc_magic == SMB_MBC_MAGIC)
304 
305 typedef struct mbuf_chain {
306 	uint32_t		mbc_magic;
307 	volatile uint32_t	flags;		/* Various flags */
308 	struct mbuf_chain	*shadow_of;	/* I'm shadowing someone */
309 	mbuf_t			*chain;		/* Start of chain */
310 	int32_t			max_bytes;	/* max # of bytes for chain */
311 	int32_t			chain_offset;	/* Current offset into chain */
312 } mbuf_chain_t;
313 
314 mbuf_t *smb_mbuf_alloc_ext(caddr_t, int, m_ext_free_t, void *);
315 
316 mbuf_t *smb_mbuf_alloc(void);
317 void smb_mbuf_free(mbuf_t *);
318 
319 void *smb_mbufcl_alloc(void);
320 void smb_mbufcl_free(mbuf_t *);
321 
322 mbuf_t *m_prepend(struct mbuf *m, int plen, int how);
323 void m_adjust(mbuf_t *, int);
324 mbuf_t *m_free(mbuf_t *);
325 void m_freem(mbuf_t *);
326 void smb_mbc_init(void);
327 void smb_mbc_fini(void);
328 mbuf_chain_t *smb_mbc_alloc(uint32_t);
329 void smb_mbc_free(mbuf_chain_t *);
330 
331 #ifdef __cplusplus
332 }
333 #endif
334 
335 #endif /* _SMBSRV_MBUF_H */
336