mbuf.h

ReactOS是一些高手根据Windows XP的内核编写出的类XP。内核实现机理和API函数调用几乎相同。甚至可以兼容XP的程序。喜欢研究系统内核的人可以看一看。

 * pointer while on the free list.
 */
union mcluster {
	union	mcluster *mcl_next;
	char	mcl_buf[MCLBYTES];
};

#define	MCLALLOC(p, how) \
	MBUFLOCK( \
          OS_DbgPrint(OSK_MID_TRACE,("(MCLALLOC)\n")); \
	  if (mclfree == 0) \
		(void)m_clalloc(1, (how)); \
	  (p) = (caddr_t)mclfree; \
	  if ((p)) { \
		++mclrefcnt[mtocl(p)]; \
		mbstat.m_clfree--; \
		mclfree = ((union mcluster *)(p))->mcl_next; \
	  } \
	)

#ifdef __REACTOS__
#define MCLGET(m, how) { \
          OS_DbgPrint(OSK_MID_TRACE,("(MCLGET) m = %x\n", m)); \
          (m)->m_ext.ext_buf = malloc(MCLBYTES,__FILE__,__LINE__); \
	  if ((m)->m_ext.ext_buf != NULL) { \
              (m)->m_data = (m)->m_ext.ext_buf; \
              (m)->m_flags |= M_EXT; \
              (m)->m_ext.ext_size = MCLBYTES; \
          } \
        }

#define MCLFREE(p) { \
          free( (p), 0 ); \
        }
#else
#define	MCLGET(m, how) \
	{ MCLALLOC((m)->m_ext.ext_buf, (how)); \
          OS_DbgPrint(OSK_MID_TRACE,("(MCLGET) m = %x\n", m)); \
	  if ((m)->m_ext.ext_buf != NULL) { \
		(m)->m_data = (m)->m_ext.ext_buf; \
		(m)->m_flags |= M_EXT; \
		(m)->m_ext.ext_size = MCLBYTES;  \
	  } \
	}

#define	MCLFREE(p) \
	MBUFLOCK ( \
          OS_DbgPrint(OSK_MID_TRACE,("(MCLFREE)\n")); \
	  if (--mclrefcnt[mtocl(p)] == 0) { \
		((union mcluster *)(p))->mcl_next = mclfree; \
		mclfree = (union mcluster *)(p); \
		mbstat.m_clfree++; \
	  } \
	)
#endif
#else
#define	MCLGET(m, how) \
	{ (m)->m_ext.ext_bufio = oskit_bufio_create(MCLBYTES); \
          OS_DbgPrint(OSK_MID_TRACE,("(!OSKIT MCLGET)\n")); \
	  oskit_bufio_map((m)->m_ext.ext_bufio, \
		(void **)&((m)->m_ext.ext_buf), 0, MCLBYTES);	\
	  if ((m)->m_ext.ext_buf != NULL) { \
		(m)->m_data = (m)->m_ext.ext_buf; \
		(m)->m_flags |= M_EXT; \
		(m)->m_ext.ext_size = MCLBYTES;  \
	  } \
	}
#endif /* !OSKIT */

/*
 * MFREE(struct mbuf *m, struct mbuf *n)
 * Free a single mbuf and associated external storage.
 * Place the successor, if any, in n.
 */
#ifdef notyet
#define	MFREE(m, n) \
	{ MBUFLOCK(mbstat.m_mtypes[(m)->m_type]--;) \
	  if ((m)->m_flags & M_EXT) { \
		if ((m)->m_ext.ext_free) \
			(*((m)->m_ext.ext_free))((m)->m_ext.ext_buf, \
			    (m)->m_ext.ext_size); \
		else \
			MCLFREE((m)->m_ext.ext_buf); \
	  } \
	  (n) = (m)->m_next; \
	  FREE((m), mbtypes[(m)->m_type]); \
	  m = NULL; \
	}
#else /* notyet */
#ifdef OSKIT
#define	MFREE(m, nn) \
	{ MBUFLOCK(mbstat.m_mtypes[(m)->m_type]--;) \
          OS_DbgPrint(OSK_MID_TRACE,("(OSKIT MFREE) m = %x\n", m)); \
	  if ((m)->m_flags & M_EXT) { \
		oskit_bufio_release((m)->m_ext.ext_bufio);	\
	  } \
	  (nn) = (m)->m_next; \
	  FREE((m), mbtypes[(m)->m_type]); \
	  m = NULL; \
	}
#else /* !OSKIT */
#define	MFREE(m, nn) \
	{ MBUFLOCK(mbstat.m_mtypes[(m)->m_type]--;) \
          OS_DbgPrint(OSK_MID_TRACE,("(!OSKIT MFREE) m = %x\n", m)); \
	  if ((m)->m_flags & M_EXT) { \
		MCLFREE((m)->m_ext.ext_buf); \
	  } \
	  (nn) = (m)->m_next; \
	  FREE((m), mbtypes[(m)->m_type]); \
	  m = NULL; \
	}
#endif /* OSKIT */
#endif

/*
 * Copy mbuf pkthdr from from to to.
 * from must have M_PKTHDR set, and to must be empty.
 */
#define	M_COPY_PKTHDR(to, from) { \
        OS_DbgPrint(OSK_MID_TRACE,("(M_COPY_PKTHDR) to %x from %x\n", to, from)); \
	(to)->m_pkthdr = (from)->m_pkthdr; \
	(to)->m_flags = (from)->m_flags & M_COPYFLAGS; \
	(to)->m_data = (to)->m_pktdat; \
}

/*
 * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place
 * an object of the specified size at the end of the mbuf, longword aligned.
 */
#define	M_ALIGN(m, len) \
	{ \
          OS_DbgPrint(OSK_MID_TRACE,("(M_ALIGN) %d @ %x\n", m, len)); \
          (m)->m_data += (MLEN - (len)) &~ (sizeof(long) - 1); \
        }
/*
 * As above, for mbufs allocated with m_gethdr/MGETHDR
 * or initialized by M_COPY_PKTHDR.
 */
#define	MH_ALIGN(m, len) \
	{ \
          OS_DbgPrint(OSK_MID_TRACE,("(MH_ALIGN) %d @ %x\n", m, len)); \
          (m)->m_data += (MHLEN - (len)) &~ (sizeof(long) - 1); \
        }

/*
 * Compute the amount of space available
 * before the current start of data in an mbuf.
 */
#ifdef OSKIT
/* Be bold and strong: why shouldn't that work??? */
#define	M_LEADINGSPACE(m) \
	((m)->m_flags & M_EXT ? (m)->m_data - (m)->m_ext.ext_buf : \
	    (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \
	    (m)->m_data - (m)->m_dat)
#else
#define	M_LEADINGSPACE(m) \
	((m)->m_flags & M_EXT ? /* (m)->m_data - (m)->m_ext.ext_buf */ 0 : \
	    (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \
	    (m)->m_data - (m)->m_dat)
#endif /* OSKIT */

/*
 * Compute the amount of space available
 * after the end of data in an mbuf.
 */
#define	M_TRAILINGSPACE(m) \
        OS_DbgPrint(OSK_MID_TRACE,("(M_TRAILINGSPACE) %x\n", m)); \
	((m)->m_flags & M_EXT ? (m)->m_ext.ext_buf + (m)->m_ext.ext_size - \
	    ((m)->m_data + (m)->m_len) : \
	    &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len))

/*
 * Arrange to prepend space of size plen to mbuf m.
 * If a new mbuf must be allocated, how specifies whether to wait.
 * If how is M_DONTWAIT and allocation fails, the original mbuf chain
 * is freed and m is set to NULL.
 */
#define	M_PREPEND(m, plen, how) { \
        OS_DbgPrint(OSK_MID_TRACE,("(M_PREPEND) %d on %x\n", plen, m)); \
	if (M_LEADINGSPACE(m) >= (plen)) { \
		(m)->m_data -= (plen); \
		(m)->m_len += (plen); \
	} else \
		(m) = m_prepend((m), (plen), (how)); \
	if ((m) && (m)->m_flags & M_PKTHDR) \
		(m)->m_pkthdr.len += (plen); \
}

/* change mbuf to new type */
#define MCHTYPE(m, t) { \
        OS_DbgPrint(OSK_MID_TRACE,("(MCHTYPE) %x %x\n", m, t)); \
	MBUFLOCK(mbstat.m_mtypes[(m)->m_type]--; mbstat.m_mtypes[t]++;) \
	(m)->m_type = t;\
}

/* length to m_copy to copy all */
#define	M_COPYALL	1000000000

/* compatiblity with 4.3 */
#define  m_copy(m, o, l)	m_copym((m), (o), (l), M_DONTWAIT)

/*
 * Mbuf statistics.
 */
struct mbstat {
	u_long	m_mbufs;	/* mbufs obtained from page pool */
	u_long	m_clusters;	/* clusters obtained from page pool */
	u_long	m_spare;	/* spare field */
	u_long	m_clfree;	/* free clusters */
	u_long	m_drops;	/* times failed to find space */
	u_long	m_wait;		/* times waited for space */
	u_long	m_drain;	/* times drained protocols for space */
	u_short	m_mtypes[256];	/* type specific mbuf allocations */
};

#ifdef	KERNEL
#ifndef OSKIT
extern	struct mbuf *mbutl;		/* virtual address of mclusters */
extern	char *mclrefcnt;		/* cluster reference counts */
#endif /* !OSKIT */
struct	mbstat mbstat;
#ifndef OSKIT
extern	int nmbclusters;
union	mcluster *mclfree;
#endif /* !OSKIT */
int	max_linkhdr;			/* largest link-level header */
int	max_protohdr;			/* largest protocol header */
int	max_hdr;			/* largest link+protocol header */
int	max_datalen;			/* MHLEN - max_hdr */
extern	int mbtypes[];			/* XXX */

int	m_clalloc __P((int, int));
void	m_copyback __P((struct mbuf *, int, int, caddr_t));
struct	mbuf *m_retry __P((int, int));
struct	mbuf *m_retryhdr __P((int, int));
void	m_reclaim __P((void));
struct	mbuf *m_get __P((int, int));
struct	mbuf *m_gethdr __P((int, int));
struct	mbuf *m_getclr __P((int, int));
struct	mbuf *m_free __P((struct mbuf *));
void	m_freem __P((struct mbuf *));
struct	mbuf *m_prepend __P((struct mbuf *,int,int));
struct	mbuf *m_copym __P((struct mbuf *, int, int, int));
void	m_copydata __P((struct mbuf *,int,int,caddr_t));
void	m_cat __P((struct mbuf *,struct mbuf *));
void	m_adj __P((struct mbuf *,int));
struct	mbuf *m_pullup __P((struct mbuf *, int));
struct	mbuf *m_split __P((struct mbuf *,int,int));
struct	mbuf *m_devget __P((char *, int, int, struct ifnet *,
			    void (*copy)(struct mbuf *, caddr_t, u_int)));

#ifdef MBTYPES
int mbtypes[] = {				/* XXX */
	M_FREE,		/* MT_FREE	0	   should be on free list */
	M_MBUF,		/* MT_DATA	1	   dynamic (data) allocation */
	M_MBUF,		/* MT_HEADER	2	   packet header */
	M_SOCKET,	/* MT_SOCKET	3	   socket structure */
	M_PCB,		/* MT_PCB	4	   protocol control block */
	M_RTABLE,	/* MT_RTABLE	5	   routing tables */
	M_HTABLE,	/* MT_HTABLE	6	   IMP host tables */
	0,		/* MT_ATABLE	7	   address resolution tables */
	M_MBUF,		/* MT_SONAME	8	   socket name */
	0,		/* 		9 */
	M_SOOPTS,	/* MT_SOOPTS	10	   socket options */
	M_FTABLE,	/* MT_FTABLE	11	   fragment reassembly header */
	M_MBUF,		/* MT_RIGHTS	12	   access rights */
	M_IFADDR,	/* MT_IFADDR	13	   interface address */
	M_MBUF,		/* MT_CONTROL	14	   extra-data protocol message */
	M_MBUF,		/* MT_OOBDATA	15	   expedited data  */
#ifdef DATAKIT
	25, 26, 27, 28, 29, 30, 31, 32		/* datakit ugliness */
#endif
};
#endif
#endif

#ifdef LOCAL_OSKIT_DEFINED
#undef LOCAL_OSKIT_DEFINED
#undef OSKIT
#endif

#endif /* !_SYS_MBUF_H_ */