1 /* init_main.c 4.6 02/16/81 */ 2 3 #include "../h/param.h" 4 #include "../h/systm.h" 5 #include "../h/dir.h" 6 #include "../h/user.h" 7 #include "../h/filsys.h" 8 #include "../h/mount.h" 9 #include "../h/map.h" 10 #include "../h/proc.h" 11 #include "../h/inode.h" 12 #include "../h/seg.h" 13 #include "../h/conf.h" 14 #include "../h/buf.h" 15 #include "../h/mtpr.h" 16 #include "../h/pte.h" 17 #include "../h/clock.h" 18 #include "../h/vm.h" 19 #include "../h/cmap.h" 20 #include "../h/text.h" 21 #include "../h/vlimit.h" 22 23 /* 24 * Initialization code. 25 * Called from cold start routine as 26 * soon as a stack and segmentation 27 * have been established. 28 * Functions: 29 * clear and free user core 30 * turn on clock 31 * hand craft 0th process 32 * call all initialization routines 33 * fork - process 0 to schedule 34 * - process 2 to page out 35 * - process 1 execute bootstrap 36 * 37 * loop at loc 13 (0xd) in user mode -- /etc/init 38 * cannot be executed. 39 */ 40 main(firstaddr) 41 { 42 register int i; 43 register struct proc *p; 44 45 #ifdef FASTVAX 46 rqinit(); 47 #endif 48 startup(firstaddr); 49 if (lotsfree == 0) 50 lotsfree = LOTSFREE; 51 52 /* 53 * set up system process 0 (swapper) 54 */ 55 p = &proc[0]; 56 p->p_p0br = (struct pte *)mfpr(P0BR); 57 p->p_szpt = 1; 58 p->p_addr = uaddr(p); 59 p->p_stat = SRUN; 60 p->p_flag |= SLOAD|SSYS; 61 p->p_nice = NZERO; 62 setredzone(p->p_addr, (caddr_t)&u); 63 u.u_procp = p; 64 u.u_cmask = CMASK; 65 for (i = 1; i < sizeof(u.u_limit)/sizeof(u.u_limit[0]); i++) 66 switch (i) { 67 68 case LIM_STACK: 69 u.u_limit[i] = 512*1024; 70 continue; 71 case LIM_DATA: 72 u.u_limit[i] = ctob(MAXDSIZ); 73 continue; 74 default: 75 u.u_limit[i] = INFINITY; 76 continue; 77 } 78 clkstart(); 79 80 /* 81 * Initialize devices and 82 * set up 'known' i-nodes 83 */ 84 85 ihinit(); 86 bhinit(); 87 cinit(); 88 binit(); 89 bswinit(); 90 iinit(); 91 rootdir = iget(rootdev, (ino_t)ROOTINO); 92 rootdir->i_flag &= ~ILOCK; 93 u.u_cdir = iget(rootdev, (ino_t)ROOTINO); 94 u.u_cdir->i_flag &= ~ILOCK; 95 u.u_rdir = NULL; 96 u.u_dmap = zdmap; 97 u.u_smap = zdmap; 98 99 /* 100 * make page-out daemon (process 2) 101 * the daemon has ctopt(NSWBUF*CLSIZE*KLMAX) pages of page 102 * table so that it can map dirty pages into 103 * its address space during asychronous pushes. 104 */ 105 106 mpid = 1; 107 proc[0].p_szpt = clrnd(ctopt(NSWBUF*CLSIZE*KLMAX + UPAGES)); 108 proc[1].p_stat = SZOMB; /* force it to be in proc slot 2 */ 109 if (newproc(0)) { 110 proc[2].p_flag |= SLOAD|SSYS; 111 proc[2].p_dsize = u.u_dsize = NSWBUF*CLSIZE*KLMAX; 112 pageout(); 113 } 114 115 /* 116 * make init process and 117 * enter scheduling loop 118 */ 119 120 mpid = 0; 121 proc[1].p_stat = 0; 122 proc[0].p_szpt = CLSIZE; 123 if (newproc(0)) { 124 expand(clrnd((int)btoc(szicode)), P0BR); 125 (void) swpexpand(u.u_dsize, 0, &u.u_dmap, &u.u_smap); 126 (void) copyout((caddr_t)icode, (caddr_t)0, (unsigned)szicode); 127 /* 128 * Return goes to loc. 0 of user init 129 * code just copied out. 130 */ 131 return; 132 } 133 proc[0].p_szpt = 1; 134 sched(); 135 } 136 137 /* 138 * iinit is called once (from main) 139 * very early in initialization. 140 * It reads the root's super block 141 * and initializes the current date 142 * from the last modified date. 143 * 144 * panic: iinit -- cannot read the super 145 * block. Usually because of an IO error. 146 */ 147 iinit() 148 { 149 register struct buf *bp; 150 register struct filsys *fp; 151 152 (*bdevsw[major(rootdev)].d_open)(rootdev, 1); 153 bp = bread(rootdev, SUPERB); 154 if(u.u_error) 155 panic("iinit"); 156 bp->b_flags |= B_LOCKED; /* block can never be re-used */ 157 brelse(bp); 158 mount[0].m_dev = rootdev; 159 mount[0].m_bufp = bp; 160 fp = bp->b_un.b_filsys; 161 fp->s_flock = 0; 162 fp->s_ilock = 0; 163 fp->s_ronly = 0; 164 fp->s_lasti = 1; 165 fp->s_nbehind = 0; 166 clkinit(fp->s_time); 167 bootime = time; 168 } 169 170 /* 171 * This is the set of buffers proper, whose heads 172 * were declared in buf.h. There can exist buffer 173 * headers not pointing here that are used purely 174 * as arguments to the I/O routines to describe 175 * I/O to be done-- e.g. swap headers swbuf[] for 176 * swapping. 177 * 178 * These are actually allocated kernel map slots and space is 179 * allocated in locore.s for them. 180 */ 181 char buffers[NBUF][BSIZE]; 182 183 /* 184 * Initialize the buffer I/O system by freeing 185 * all buffers and setting all device buffer lists to empty. 186 */ 187 binit() 188 { 189 register struct buf *bp; 190 register struct buf *dp; 191 register int i; 192 struct bdevsw *bdp; 193 struct swdevt *swp; 194 195 for (dp = bfreelist; dp < &bfreelist[BQUEUES]; dp++) { 196 dp->b_forw = dp->b_back = dp->av_forw = dp->av_back = dp; 197 dp->b_flags = B_HEAD; 198 } 199 dp--; /* dp = &bfreelist[BQUEUES-1]; */ 200 for (i=0; i<NBUF; i++) { 201 bp = &buf[i]; 202 bp->b_dev = NODEV; 203 bp->b_un.b_addr = buffers[i]; 204 bp->b_back = dp; 205 bp->b_forw = dp->b_forw; 206 dp->b_forw->b_back = bp; 207 dp->b_forw = bp; 208 bp->b_flags = B_BUSY|B_INVAL; 209 brelse(bp); 210 } 211 for (bdp = bdevsw; bdp->d_open; bdp++) 212 nblkdev++; 213 /* 214 * Count swap devices, and adjust total swap space available. 215 * Some of this space will not be available until a vswapon() 216 * system is issued, usually when the system goes multi-user. 217 */ 218 nswdev = 0; 219 for (swp = swdevt; swp->sw_dev; swp++) 220 nswdev++; 221 if (nswdev == 0) 222 panic("binit"); 223 nswap *= nswdev; 224 maxpgio *= nswdev; 225 swfree(0); 226 } 227 228 /* 229 * Initialize linked list of free swap 230 * headers. These do not actually point 231 * to buffers, but rather to pages that 232 * are being swapped in and out. 233 */ 234 bswinit() 235 { 236 register int i; 237 238 bswlist.av_forw = &swbuf[0]; 239 for (i=0; i<NSWBUF-1; i++) 240 swbuf[i].av_forw = &swbuf[i+1]; 241 swbuf[NSWBUF-1].av_forw = NULL; 242 } 243