1 /* mbuf.h 4.16 82/12/14 */ 2 3 /* 4 * Constants related to memory allocator. 5 */ 6 #define MSIZE 128 /* size of an mbuf */ 7 #define MMINOFF 12 /* mbuf header length */ 8 #define MTAIL 4 9 #define MMAXOFF (MSIZE-MTAIL) /* offset where data ends */ 10 #define MLEN (MSIZE-MMINOFF-MTAIL) /* mbuf data length */ 11 #define NMBCLUSTERS 256 12 #define NMBPCL (CLBYTES/MSIZE) /* # mbufs per cluster */ 13 14 /* 15 * Macros for type conversion 16 */ 17 18 /* network cluster number to virtual address, and back */ 19 #define cltom(x) ((struct mbuf *)((int)mbutl + ((x) << CLSHIFT))) 20 #define mtocl(x) (((int)x - (int)mbutl) >> CLSHIFT) 21 22 /* address in mbuf to mbuf head */ 23 #define dtom(x) ((struct mbuf *)((int)x & ~(MSIZE-1))) 24 25 /* mbuf head, to typed data */ 26 #define mtod(x,t) ((t)((int)(x) + (x)->m_off)) 27 28 struct mbuf { 29 struct mbuf *m_next; /* next buffer in chain */ 30 u_long m_off; /* offset of data */ 31 short m_len; /* amount of data in this mbuf */ 32 short m_type; /* mbuf type (0 == free) */ 33 u_char m_dat[MLEN]; /* data storage */ 34 struct mbuf *m_act; /* link in higher-level mbuf list */ 35 }; 36 37 /* mbuf types */ 38 #define MT_FREE 0 /* should be on free list */ 39 #define MT_DATA 1 /* dynamic (data) allocation */ 40 #define MT_HEADER 2 /* packet header */ 41 #define MT_SOCKET 3 /* socket structure */ 42 #define MT_PCB 4 /* protocol control block */ 43 #define MT_RTABLE 5 /* routing tables */ 44 #define MT_HTABLE 6 /* IMP host tables */ 45 #define MT_ATABLE 7 /* address resolution tables */ 46 #define MT_SONAME 8 /* socket name */ 47 #define MT_ZOMBIE 9 /* zombie proc status */ 48 #define MT_SOOPTS 10 /* socket options */ 49 #define MT_FTABLE 11 /* fragment reassembly header */ 50 51 /* flags to m_get */ 52 #define M_DONTWAIT 0 53 #define M_WAIT 1 54 55 /* flags to m_pgalloc */ 56 #define MPG_MBUFS 0 /* put new mbufs on free list */ 57 #define MPG_CLUSTERS 1 /* put new clusters on free list */ 58 #define MPG_SPACE 2 /* don't free; caller wants space */ 59 60 /* length to m_copy to copy all */ 61 #define M_COPYALL 1000000000 62 63 #define MGET(m, i, t) \ 64 { int ms = splimp(); \ 65 if ((m)=mfree) \ 66 { if ((m)->m_type != MT_FREE) panic("mget"); (m)->m_type = t; \ 67 mbstat.m_mbfree--; mbstat.m_mtypes[t]++; \ 68 mfree = (m)->m_next; (m)->m_next = 0; \ 69 (m)->m_off = MMINOFF; } \ 70 else \ 71 (m) = m_more(i, t); \ 72 splx(ms); } 73 #define MCLGET(m, i) \ 74 { int ms = splimp(); \ 75 if ((m)=mclfree) \ 76 {++mclrefcnt[mtocl(m)];mbstat.m_clfree--;mclfree = (m)->m_next;} \ 77 splx(ms); } 78 #define MFREE(m, n) \ 79 { int ms = splimp(); \ 80 if ((m)->m_type == MT_FREE) panic("mfree"); \ 81 mbstat.m_mtypes[(m)->m_type]--; (m)->m_type = MT_FREE; \ 82 if ((m)->m_off > MSIZE) { \ 83 (n) = (struct mbuf *)(mtod(m, int)&~0x3ff); \ 84 if (--mclrefcnt[mtocl(n)] == 0) \ 85 { (n)->m_next = mclfree;mclfree = (n);mbstat.m_clfree++;} \ 86 } \ 87 (n) = (m)->m_next; (m)->m_next = mfree; \ 88 (m)->m_off = 0; (m)->m_act = 0; mfree = (m); mbstat.m_mbfree++; \ 89 splx(ms); } 90 91 /* 92 * Mbuf statistics. 93 */ 94 struct mbstat { 95 short m_mbufs; /* mbufs obtained from page pool */ 96 short m_mbfree; /* mbufs on our free list */ 97 short m_clusters; /* clusters obtained from page pool */ 98 short m_clfree; /* free clusters */ 99 short m_drops; /* times failed to find space */ 100 short m_mtypes[32]; /* type specific mbuf allocations */ 101 }; 102 103 #ifdef KERNEL 104 extern struct mbuf mbutl[]; /* virtual address of net free mem */ 105 extern struct pte Mbmap[]; /* page tables to map Netutl */ 106 struct mbstat mbstat; 107 int nmbclusters; 108 struct mbuf *mfree, *mclfree; 109 char mclrefcnt[NMBCLUSTERS]; 110 struct mbuf *m_get(),*m_getclr(),*m_free(),*m_more(),*m_copy(),*m_pullup(); 111 caddr_t m_clalloc(); 112 #endif 113