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      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 
     59 
     60 /* mbuf initialization function */
     61 void mbuf_init(void *);
     62 
     63 #define	M_MOVE_PKTHDR(to, from)	m_move_pkthdr((to), (from))
     64 #define	MGET(m, how, type)	((m) = m_get((how), (type)))
     65 #define	MGETHDR(m, how, type)	((m) = m_gethdr((how), (type)))
     66 #define	MCLGET(m, how)		m_clget((m), (how))
     67 
     68 
     69 #define M_HDR_PAD ((sizeof(intptr_t)==4) ? 2 : 6) /* modified for __Userspace__ */
     70 
     71 /* Length to m_copy to copy all. */
     72 #define	M_COPYALL	1000000000
     73 
     74 /* umem_cache_t is defined in user_include/umem.h as
     75  * typedef struct umem_cache umem_cache_t;
     76  * Note:umem_zone_t is a pointer.
     77  */
     78 #if defined(SCTP_SIMPLE_ALLOCATOR)
     79 typedef size_t sctp_zone_t;
     80 #else
     81 typedef umem_cache_t *sctp_zone_t;
     82 #endif
     83 
     84 extern sctp_zone_t zone_mbuf;
     85 extern sctp_zone_t zone_clust;
     86 extern sctp_zone_t zone_ext_refcnt;
     87 
     88 /*-
     89  * Macros for type conversion:
     90  * mtod(m, t)	-- Convert mbuf pointer to data pointer of correct type.
     91  * dtom(x)	-- Convert data pointer within mbuf to mbuf pointer (XXX).
     92  */
     93 #define	mtod(m, t)	((t)((m)->m_data))
     94 #define	dtom(x)		((struct mbuf *)((intptr_t)(x) & ~(MSIZE-1)))
     95 
     96 struct mb_args {
     97 	int	flags;	/* Flags for mbuf being allocated */
     98 	short	type;	/* Type of mbuf being allocated */
     99 };
    100 
    101 struct clust_args {
    102 	struct mbuf * parent_mbuf;
    103 };
    104 
    105 struct mbuf *    m_split(struct mbuf *, int, int);
    106 void             m_cat(struct mbuf *m, struct mbuf *n);
    107 void		 m_adj(struct mbuf *, int);
    108 void  mb_free_ext(struct mbuf *);
    109 void  m_freem(struct mbuf *);
    110 struct m_tag	*m_tag_alloc(u_int32_t, int, int, int);
    111 struct mbuf	*m_copym(struct mbuf *, int, int, int);
    112 void		 m_copyback(struct mbuf *, int, int, caddr_t);
    113 struct mbuf	*m_pullup(struct mbuf *, int);
    114 struct mbuf	*m_pulldown(struct mbuf *, int off, int len, int *offp);
    115 int		 m_dup_pkthdr(struct mbuf *, struct mbuf *, int);
    116 struct m_tag	*m_tag_copy(struct m_tag *, int);
    117 int		 m_tag_copy_chain(struct mbuf *, struct mbuf *, int);
    118 struct mbuf	*m_prepend(struct mbuf *, int, int);
    119 void		 m_copydata(const struct mbuf *, int, int, caddr_t);
    120 
    121 #define MBUF_MEM_NAME "mbuf"
    122 #define MBUF_CLUSTER_MEM_NAME "mbuf_cluster"
    123 #define	MBUF_EXTREFCNT_MEM_NAME	"mbuf_ext_refcnt"
    124 
    125 #define	MT_NOINIT	255	/* Not a type but a flag to allocate
    126 				   a non-initialized mbuf */
    127 
    128 /*
    129  * General mbuf allocator statistics structure.
    130  * __Userspace__ mbstat may be useful for gathering statistics.
    131  * In the kernel many of these statistics are no longer used as
    132  * they track allocator statistics through kernel UMA's built in statistics mechanism.
    133  */
    134 struct mbstat {
    135 	u_long	m_mbufs;	/* XXX */
    136 	u_long	m_mclusts;	/* XXX */
    137 
    138 	u_long	m_drain;	/* times drained protocols for space */
    139 	u_long	m_mcfail;	/* XXX: times m_copym failed */
    140 	u_long	m_mpfail;	/* XXX: times m_pullup failed */
    141 	u_long	m_msize;	/* length of an mbuf */
    142 	u_long	m_mclbytes;	/* length of an mbuf cluster */
    143 	u_long	m_minclsize;	/* min length of data to allocate a cluster */
    144 	u_long	m_mlen;		/* length of data in an mbuf */
    145 	u_long	m_mhlen;	/* length of data in a header mbuf */
    146 
    147 	/* Number of mbtypes (gives # elems in mbtypes[] array: */
    148 	short	m_numtypes;
    149 
    150 	/* XXX: Sendfile stats should eventually move to their own struct */
    151 	u_long	sf_iocnt;	/* times sendfile had to do disk I/O */
    152 	u_long	sf_allocfail;	/* times sfbuf allocation failed */
    153 	u_long	sf_allocwait;	/* times sfbuf allocation had to wait */
    154 };
    155 
    156 
    157 /*
    158  * Mbufs are of a single size, MSIZE (sys/param.h), which includes overhead.
    159  * An mbuf may add a single "mbuf cluster" of size MCLBYTES (also in
    160  * sys/param.h), which has no additional overhead and is used instead of the
    161  * internal data area; this is done when at least MINCLSIZE of data must be
    162  * stored.  Additionally, it is possible to allocate a separate buffer
    163  * externally and attach it to the mbuf in a way similar to that of mbuf
    164  * clusters.
    165  */
    166 #define	MLEN		((int)(MSIZE - sizeof(struct m_hdr)))	/* normal data len */
    167 #define	MHLEN		((int)(MLEN - sizeof(struct pkthdr)))	/* data len w/pkthdr */
    168 #define	MINCLSIZE	((int)(MHLEN + 1))	/* smallest amount to put in cluster */
    169 #define	M_MAXCOMPRESS	(MHLEN / 2)	/* max amount to copy for compression */
    170 
    171 
    172 /*
    173  * Header present at the beginning of every mbuf.
    174  */
    175 struct m_hdr {
    176 	struct mbuf	*mh_next;	/* next buffer in chain */
    177 	struct mbuf	*mh_nextpkt;	/* next chain in queue/record */
    178 	caddr_t		 mh_data;	/* location of data */
    179 	int		 mh_len;	/* amount of data in this mbuf */
    180 	int		 mh_flags;	/* flags; see below */
    181 	short		 mh_type;	/* type of data in this mbuf */
    182 	uint8_t          pad[M_HDR_PAD];/* word align                  */
    183 };
    184 
    185 /*
    186  * Packet tag structure (see below for details).
    187  */
    188 struct m_tag {
    189 	SLIST_ENTRY(m_tag)	m_tag_link;	/* List of packet tags */
    190 	u_int16_t		m_tag_id;	/* Tag ID */
    191 	u_int16_t		m_tag_len;	/* Length of data */
    192 	u_int32_t		m_tag_cookie;	/* ABI/Module ID */
    193 	void			(*m_tag_free)(struct m_tag *);
    194 };
    195 
    196 /*
    197  * Record/packet header in first mbuf of chain; valid only if M_PKTHDR is set.
    198  */
    199 struct pkthdr {
    200 	struct ifnet	*rcvif;		/* rcv interface */
    201 	/* variables for ip and tcp reassembly */
    202 	void		*header;	/* pointer to packet header */
    203 	int		 len;		/* total packet length */
    204 	/* variables for hardware checksum */
    205 	int		 csum_flags;	/* flags regarding checksum */
    206 	int		 csum_data;	/* data field used by csum routines */
    207 	u_int16_t	 tso_segsz;	/* TSO segment size */
    208 	u_int16_t	 ether_vtag;	/* Ethernet 802.1p+q vlan tag */
    209 	SLIST_HEAD(packet_tags, m_tag) tags; /* list of packet tags */
    210 };
    211 
    212 /*
    213  * Description of external storage mapped into mbuf; valid only if M_EXT is
    214  * set.
    215  */
    216 struct m_ext {
    217 	caddr_t		 ext_buf;	/* start of buffer */
    218 	void		(*ext_free)	/* free routine if not the usual */
    219 			    (void *, void *);
    220 	void		*ext_args;	/* optional argument pointer */
    221 	u_int		 ext_size;	/* size of buffer, for ext_free */
    222 	volatile u_int	*ref_cnt;	/* pointer to ref count info */
    223 	int		 ext_type;	/* type of external storage */
    224 };
    225 
    226 
    227 /*
    228  * The core of the mbuf object along with some shortcut defined for practical
    229  * purposes.
    230  */
    231 struct mbuf {
    232 	struct m_hdr	m_hdr;
    233 	union {
    234 		struct {
    235 			struct pkthdr	MH_pkthdr;	/* M_PKTHDR set */
    236 			union {
    237 				struct m_ext	MH_ext;	/* M_EXT set */
    238 				char		MH_databuf[MHLEN];
    239 			} MH_dat;
    240 		} MH;
    241 		char	M_databuf[MLEN];		/* !M_PKTHDR, !M_EXT */
    242 	} M_dat;
    243 };
    244 
    245 #define	m_next		m_hdr.mh_next
    246 #define	m_len		m_hdr.mh_len
    247 #define	m_data		m_hdr.mh_data
    248 #define	m_type		m_hdr.mh_type
    249 #define	m_flags		m_hdr.mh_flags
    250 #define	m_nextpkt	m_hdr.mh_nextpkt
    251 #define	m_act		m_nextpkt
    252 #define	m_pkthdr	M_dat.MH.MH_pkthdr
    253 #define	m_ext		M_dat.MH.MH_dat.MH_ext
    254 #define	m_pktdat	M_dat.MH.MH_dat.MH_databuf
    255 #define	m_dat		M_dat.M_databuf
    256 
    257 
    258 /*
    259  * mbuf flags.
    260  */
    261 #define	M_EXT		0x0001	/* has associated external storage */
    262 #define	M_PKTHDR	0x0002	/* start of record */
    263 #define	M_EOR		0x0004	/* end of record */
    264 #define	M_RDONLY	0x0008	/* associated data is marked read-only */
    265 #define	M_PROTO1	0x0010	/* protocol-specific */
    266 #define	M_PROTO2	0x0020	/* protocol-specific */
    267 #define	M_PROTO3	0x0040	/* protocol-specific */
    268 #define	M_PROTO4	0x0080	/* protocol-specific */
    269 #define	M_PROTO5	0x0100	/* protocol-specific */
    270 #define	M_SKIP_FIREWALL	0x4000	/* skip firewall processing */
    271 #define	M_FREELIST	0x8000	/* mbuf is on the free list */
    272 
    273 
    274 /*
    275  * Flags copied when copying m_pkthdr.
    276  */
    277 #define	M_COPYFLAGS	(M_PKTHDR|M_EOR|M_RDONLY|M_PROTO1|M_PROTO1|M_PROTO2|\
    278 			    M_PROTO3|M_PROTO4|M_PROTO5|M_SKIP_FIREWALL|\
    279 			    M_BCAST|M_MCAST|M_FRAG|M_FIRSTFRAG|M_LASTFRAG|\
    280 			    M_VLANTAG|M_PROMISC)
    281 
    282 
    283 /*
    284  * mbuf pkthdr flags (also stored in m_flags).
    285  */
    286 #define	M_BCAST		0x0200	/* send/received as link-level broadcast */
    287 #define	M_MCAST		0x0400	/* send/received as link-level multicast */
    288 #define	M_FRAG		0x0800	/* packet is a fragment of a larger packet */
    289 #define	M_FIRSTFRAG	0x1000	/* packet is first fragment */
    290 #define	M_LASTFRAG	0x2000	/* packet is last fragment */
    291 #define	M_VLANTAG	0x10000	/* ether_vtag is valid */
    292 #define	M_PROMISC	0x20000	/* packet was not for us */
    293 #define	M_NOFREE	0x40000	/* do not free mbuf - it is embedded in the cluster */
    294 
    295 
    296 /*
    297  * External buffer types: identify ext_buf type.
    298  */
    299 #define	EXT_CLUSTER	1	/* mbuf cluster */
    300 #define	EXT_SFBUF	2	/* sendfile(2)'s sf_bufs */
    301 #define	EXT_JUMBOP	3	/* jumbo cluster 4096 bytes */
    302 #define	EXT_JUMBO9	4	/* jumbo cluster 9216 bytes */
    303 #define	EXT_JUMBO16	5	/* jumbo cluster 16184 bytes */
    304 #define	EXT_PACKET	6	/* mbuf+cluster from packet zone */
    305 #define	EXT_MBUF	7	/* external mbuf reference (M_IOVEC) */
    306 #define	EXT_NET_DRV	100	/* custom ext_buf provided by net driver(s) */
    307 #define	EXT_MOD_TYPE	200	/* custom module's ext_buf type */
    308 #define	EXT_DISPOSABLE	300	/* can throw this buffer away w/page flipping */
    309 #define	EXT_EXTREF	400	/* has externally maintained ref_cnt ptr */
    310 
    311 
    312 /*
    313  * mbuf types.
    314  */
    315 #define	MT_NOTMBUF	0	/* USED INTERNALLY ONLY! Object is not mbuf */
    316 #define	MT_DATA		1	/* dynamic (data) allocation */
    317 #define	MT_HEADER	MT_DATA	/* packet header, use M_PKTHDR instead */
    318 #define	MT_SONAME	8	/* socket name */
    319 #define	MT_CONTROL	14	/* extra-data protocol message */
    320 #define	MT_OOBDATA	15	/* expedited data  */
    321 #define	MT_NTYPES	16	/* number of mbuf types for mbtypes[] */
    322 
    323 #define	MT_NOINIT	255	/* Not a type but a flag to allocate
    324 				   a non-initialized mbuf */
    325 
    326 /*
    327  * __Userspace__ flags like M_NOWAIT are defined in malloc.h
    328  * Flags like these are used in functions like uma_zalloc()
    329  * but don't have an equivalent in userland umem
    330  * Flags specifying how an allocation should be made.
    331  *
    332  * The flag to use is as follows:
    333  * - M_DONTWAIT or M_NOWAIT from an interrupt handler to not block allocation.
    334  * - M_WAIT or M_WAITOK or M_TRYWAIT from wherever it is safe to block.
    335  *
    336  * M_DONTWAIT/M_NOWAIT means that we will not block the thread explicitly and
    337  * if we cannot allocate immediately we may return NULL, whereas
    338  * M_WAIT/M_WAITOK/M_TRYWAIT means that if we cannot allocate resources we
    339  * will block until they are available, and thus never return NULL.
    340  *
    341  * XXX Eventually just phase this out to use M_WAITOK/M_NOWAIT.
    342  */
    343 #define	MBTOM(how)	(how)
    344 
    345 void		 m_tag_delete(struct mbuf *, struct m_tag *);
    346 void		 m_tag_delete_chain(struct mbuf *, struct m_tag *);
    347 void		 m_move_pkthdr(struct mbuf *, struct mbuf *);
    348 void		 m_tag_free_default(struct m_tag *);
    349 
    350 extern int max_linkhdr;    /* Largest link-level header */
    351 extern int max_protohdr; /* Size of largest protocol layer header. See user_mbuf.c */
    352 
    353 extern struct mbstat	mbstat;		/* General mbuf stats/infos */
    354 
    355 
    356 /*
    357  * Evaluate TRUE if it's safe to write to the mbuf m's data region (this can
    358  * be both the local data payload, or an external buffer area, depending on
    359  * whether M_EXT is set).
    360  */
    361 #define	M_WRITABLE(m)	(!((m)->m_flags & M_RDONLY) &&			\
    362 			 (!(((m)->m_flags & M_EXT)) ||			\
    363 			 (*((m)->m_ext.ref_cnt) == 1)) )		\
    364 
    365 
    366 /*
    367  * Compute the amount of space available before the current start of data in
    368  * an mbuf.
    369  *
    370  * The M_WRITABLE() is a temporary, conservative safety measure: the burden
    371  * of checking writability of the mbuf data area rests solely with the caller.
    372  */
    373 #define	M_LEADINGSPACE(m)						\
    374 	((m)->m_flags & M_EXT ?						\
    375 	    (M_WRITABLE(m) ? (m)->m_data - (m)->m_ext.ext_buf : 0):	\
    376 	    (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat :	\
    377 	    (m)->m_data - (m)->m_dat)
    378 
    379 /*
    380  * Compute the amount of space available after the end of data in an mbuf.
    381  *
    382  * The M_WRITABLE() is a temporary, conservative safety measure: the burden
    383  * of checking writability of the mbuf data area rests solely with the caller.
    384  */
    385 #define	M_TRAILINGSPACE(m)						\
    386 	((m)->m_flags & M_EXT ?						\
    387 	    (M_WRITABLE(m) ? (m)->m_ext.ext_buf + (m)->m_ext.ext_size	\
    388 		- ((m)->m_data + (m)->m_len) : 0) :			\
    389 	    &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len))
    390 
    391 
    392 
    393 /*
    394  * Arrange to prepend space of size plen to mbuf m.  If a new mbuf must be
    395  * allocated, how specifies whether to wait.  If the allocation fails, the
    396  * original mbuf chain is freed and m is set to NULL.
    397  */
    398 #define	M_PREPEND(m, plen, how) do {					\
    399 	struct mbuf **_mmp = &(m);					\
    400 	struct mbuf *_mm = *_mmp;					\
    401 	int _mplen = (plen);						\
    402 	int __mhow = (how);						\
    403 									\
    404 	if (M_LEADINGSPACE(_mm) >= _mplen) {				\
    405 		_mm->m_data -= _mplen;					\
    406 		_mm->m_len += _mplen;					\
    407 	} else								\
    408 		_mm = m_prepend(_mm, _mplen, __mhow);			\
    409 	if (_mm != NULL && _mm->m_flags & M_PKTHDR)			\
    410 		_mm->m_pkthdr.len += _mplen;				\
    411 	*_mmp = _mm;							\
    412 } while (0)
    413 
    414 /*
    415  * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place an
    416  * object of the specified size at the end of the mbuf, longword aligned.
    417  */
    418 #define	M_ALIGN(m, len) do {						\
    419         KASSERT(!((m)->m_flags & (M_PKTHDR|M_EXT)),                     \
    420                 ("%s: M_ALIGN not normal mbuf", __func__));             \
    421         KASSERT((m)->m_data == (m)->m_dat,                              \
    422                 ("%s: M_ALIGN not a virgin mbuf", __func__));           \
    423 	(m)->m_data += (MLEN - (len)) & ~(sizeof(long) - 1);		\
    424 } while (0)
    425 
    426 /*
    427  * As above, for mbufs allocated with m_gethdr/MGETHDR or initialized by
    428  * M_DUP/MOVE_PKTHDR.
    429  */
    430 #define	MH_ALIGN(m, len) do {						\
    431         KASSERT((m)->m_flags & M_PKTHDR && !((m)->m_flags & M_EXT),     \
    432                 ("%s: MH_ALIGN not PKTHDR mbuf", __func__));            \
    433         KASSERT((m)->m_data == (m)->m_pktdat,                           \
    434                 ("%s: MH_ALIGN not a virgin mbuf", __func__));          \
    435 	(m)->m_data += (MHLEN - (len)) & ~(sizeof(long) - 1);		\
    436 } while (0)
    437 
    438 #endif
    439