/* mbuf.h 4.16 82/12/14 */
* Constants related to memory allocator.
#define MSIZE 128 /* size of an mbuf */
#define MMINOFF 12 /* mbuf header length */
#define MMAXOFF (MSIZE-MTAIL) /* offset where data ends */
#define MLEN (MSIZE-MMINOFF-MTAIL) /* mbuf data length */
#define NMBPCL (CLBYTES/MSIZE) /* # mbufs per cluster */
* Macros for type conversion
/* network cluster number to virtual address, and back */
#define cltom(x) ((struct mbuf *)((int)mbutl + ((x) << CLSHIFT)))
#define mtocl(x) (((int)x - (int)mbutl) >> CLSHIFT)
/* address in mbuf to mbuf head */
#define dtom(x) ((struct mbuf *)((int)x & ~(MSIZE-1)))
/* mbuf head, to typed data */
#define mtod(x,t) ((t)((int)(x) + (x)->m_off))
struct mbuf
*m_next
; /* next buffer in chain */
u_long m_off
; /* offset of data */
short m_len
; /* amount of data in this mbuf */
short m_type
; /* mbuf type (0 == free) */
u_char m_dat
[MLEN
]; /* data storage */
struct mbuf
*m_act
; /* link in higher-level mbuf list */
#define MT_FREE 0 /* should be on free list */
#define MT_DATA 1 /* dynamic (data) allocation */
#define MT_HEADER 2 /* packet header */
#define MT_SOCKET 3 /* socket structure */
#define MT_PCB 4 /* protocol control block */
#define MT_RTABLE 5 /* routing tables */
#define MT_HTABLE 6 /* IMP host tables */
#define MT_ATABLE 7 /* address resolution tables */
#define MT_SONAME 8 /* socket name */
#define MT_ZOMBIE 9 /* zombie proc status */
#define MT_SOOPTS 10 /* socket options */
#define MT_FTABLE 11 /* fragment reassembly header */
#define MPG_MBUFS 0 /* put new mbufs on free list */
#define MPG_CLUSTERS 1 /* put new clusters on free list */
#define MPG_SPACE 2 /* don't free; caller wants space */
/* length to m_copy to copy all */
#define M_COPYALL 1000000000
{ if ((m)->m_type != MT_FREE) panic("mget"); (m)->m_type = t; \
mbstat.m_mbfree--; mbstat.m_mtypes[t]++; \
mfree = (m)->m_next; (m)->m_next = 0; \
(m)->m_off = MMINOFF; } \
{++mclrefcnt[mtocl(m)];mbstat.m_clfree--;mclfree = (m)->m_next;} \
if ((m)->m_type == MT_FREE) panic("mfree"); \
mbstat.m_mtypes[(m)->m_type]--; (m)->m_type = MT_FREE; \
if ((m)->m_off > MSIZE) { \
(n) = (struct mbuf *)(mtod(m, int)&~0x3ff); \
if (--mclrefcnt[mtocl(n)] == 0) \
{ (n)->m_next = mclfree;mclfree = (n);mbstat.m_clfree++;} \
(n) = (m)->m_next; (m)->m_next = mfree; \
(m)->m_off = 0; (m)->m_act = 0; mfree = (m); mbstat.m_mbfree++; \
short m_mbufs
; /* mbufs obtained from page pool */
short m_mbfree
; /* mbufs on our free list */
short m_clusters
; /* clusters obtained from page pool */
short m_clfree
; /* free clusters */
short m_drops
; /* times failed to find space */
short m_mtypes
[32]; /* type specific mbuf allocations */
extern struct mbuf mbutl
[]; /* virtual address of net free mem */
extern struct pte Mbmap
[]; /* page tables to map Netutl */
struct mbuf
*mfree
, *mclfree
;
char mclrefcnt
[NMBCLUSTERS
];
struct mbuf
*m_get(),*m_getclr(),*m_free(),*m_more(),*m_copy(),*m_pullup();