1 /* init_main.c 4.15 81/04/28 */ 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 #include "../h/clist.h" 23 24 /* 25 * Initialization code. 26 * Called from cold start routine as 27 * soon as a stack and segmentation 28 * have been established. 29 * Functions: 30 * clear and free user core 31 * turn on clock 32 * hand craft 0th process 33 * call all initialization routines 34 * fork - process 0 to schedule 35 * - process 2 to page out 36 * - process 1 execute bootstrap 37 * 38 * loop at loc 13 (0xd) in user mode -- /etc/init 39 * cannot be executed. 40 */ 41 main(firstaddr) 42 { 43 register int i; 44 register struct proc *p; 45 46 rqinit(); 47 startup(firstaddr); 48 49 /* 50 * set up system process 0 (swapper) 51 */ 52 p = &proc[0]; 53 p->p_p0br = (struct pte *)mfpr(P0BR); 54 p->p_szpt = 1; 55 p->p_addr = uaddr(p); 56 p->p_stat = SRUN; 57 p->p_flag |= SLOAD|SSYS; 58 p->p_nice = NZERO; 59 setredzone(p->p_addr, (caddr_t)&u); 60 u.u_procp = p; 61 u.u_cmask = CMASK; 62 for (i = 1; i < sizeof(u.u_limit)/sizeof(u.u_limit[0]); i++) 63 switch (i) { 64 65 case LIM_STACK: 66 u.u_limit[i] = 512*1024; 67 continue; 68 case LIM_DATA: 69 u.u_limit[i] = ctob(MAXDSIZ); 70 continue; 71 default: 72 u.u_limit[i] = INFINITY; 73 continue; 74 } 75 p->p_maxrss = INFINITY/NBPG; 76 clkstart(); 77 78 /* 79 * Initialize devices and 80 * set up 'known' i-nodes 81 */ 82 83 ihinit(); 84 bhinit(); 85 cinit(); 86 binit(); 87 bswinit(); 88 iinit(); 89 ptinit(); 90 rootdir = iget(rootdev, (ino_t)ROOTINO); 91 rootdir->i_flag &= ~ILOCK; 92 u.u_cdir = iget(rootdev, (ino_t)ROOTINO); 93 u.u_cdir->i_flag &= ~ILOCK; 94 u.u_rdir = NULL; 95 u.u_dmap = zdmap; 96 u.u_smap = zdmap; 97 98 /* 99 * Set the scan rate and other parameters of the paging subsystem. 100 */ 101 setupclock(); 102 103 /* 104 * make page-out daemon (process 2) 105 * the daemon has ctopt(nswbuf*CLSIZE*KLMAX) pages of page 106 * table so that it can map dirty pages into 107 * its address space during asychronous pushes. 108 */ 109 110 mpid = 1; 111 proc[0].p_szpt = clrnd(ctopt(nswbuf*CLSIZE*KLMAX + UPAGES)); 112 proc[1].p_stat = SZOMB; /* force it to be in proc slot 2 */ 113 if (newproc(0)) { 114 proc[2].p_flag |= SLOAD|SSYS; 115 proc[2].p_dsize = u.u_dsize = nswbuf*CLSIZE*KLMAX; 116 pageout(); 117 } 118 119 /* 120 * make init process and 121 * enter scheduling loop 122 */ 123 124 mpid = 0; 125 proc[1].p_stat = 0; 126 proc[0].p_szpt = CLSIZE; 127 if (newproc(0)) { 128 expand(clrnd((int)btoc(szicode)), P0BR); 129 (void) swpexpand(u.u_dsize, 0, &u.u_dmap, &u.u_smap); 130 (void) copyout((caddr_t)icode, (caddr_t)0, (unsigned)szicode); 131 /* 132 * Return goes to loc. 0 of user init 133 * code just copied out. 134 */ 135 return; 136 } 137 proc[0].p_szpt = 1; 138 sched(); 139 } 140 141 /* 142 * iinit is called once (from main) 143 * very early in initialization. 144 * It reads the root's super block 145 * and initializes the current date 146 * from the last modified date. 147 * 148 * panic: iinit -- cannot read the super 149 * block. Usually because of an IO error. 150 */ 151 iinit() 152 { 153 register struct buf *bp; 154 register struct filsys *fp; 155 register int i; 156 157 (*bdevsw[major(rootdev)].d_open)(rootdev, 1); 158 bp = bread(rootdev, SUPERB); 159 if(u.u_error) 160 panic("iinit"); 161 bp->b_flags |= B_LOCKED; /* block can never be re-used */ 162 brelse(bp); 163 mount[0].m_dev = rootdev; 164 mount[0].m_bufp = bp; 165 fp = bp->b_un.b_filsys; 166 fp->s_flock = 0; 167 fp->s_ilock = 0; 168 fp->s_ronly = 0; 169 fp->s_lasti = 1; 170 fp->s_nbehind = 0; 171 fp->s_fsmnt[0] = '/'; 172 for (i = 1; i < sizeof(fp->s_fsmnt); i++) 173 fp->s_fsmnt[i] = 0; 174 clkinit(fp->s_time); 175 bootime = time; 176 } 177 178 /* 179 * Initialize the buffer I/O system by freeing 180 * all buffers and setting all device buffer lists to empty. 181 */ 182 binit() 183 { 184 register struct buf *bp; 185 register struct buf *dp; 186 register int i; 187 struct bdevsw *bdp; 188 struct swdevt *swp; 189 190 for (dp = bfreelist; dp < &bfreelist[BQUEUES]; dp++) { 191 dp->b_forw = dp->b_back = dp->av_forw = dp->av_back = dp; 192 dp->b_flags = B_HEAD; 193 } 194 dp--; /* dp = &bfreelist[BQUEUES-1]; */ 195 for (i=0; i<nbuf; i++) { 196 bp = &buf[i]; 197 bp->b_dev = NODEV; 198 bp->b_un.b_addr = buffers + i * BSIZE; 199 bp->b_back = dp; 200 bp->b_forw = dp->b_forw; 201 dp->b_forw->b_back = bp; 202 dp->b_forw = bp; 203 bp->b_flags = B_BUSY|B_INVAL; 204 brelse(bp); 205 } 206 for (bdp = bdevsw; bdp->d_open; bdp++) 207 nblkdev++; 208 /* 209 * Count swap devices, and adjust total swap space available. 210 * Some of this space will not be available until a vswapon() 211 * system is issued, usually when the system goes multi-user. 212 */ 213 nswdev = 0; 214 for (swp = swdevt; swp->sw_dev; swp++) 215 nswdev++; 216 if (nswdev == 0) 217 panic("binit"); 218 nswap *= nswdev; 219 maxpgio *= nswdev; 220 swfree(0); 221 } 222 223 /* 224 * Initialize linked list of free swap 225 * headers. These do not actually point 226 * to buffers, but rather to pages that 227 * are being swapped in and out. 228 */ 229 bswinit() 230 { 231 register int i; 232 register struct buf *sp = swbuf; 233 234 bswlist.av_forw = sp; 235 for (i=0; i<nswbuf-1; i++, sp++) 236 sp->av_forw = sp+1; 237 sp->av_forw = NULL; 238 } 239 240 /* 241 * Initialize clist by freeing all character blocks, then count 242 * number of character devices. (Once-only routine) 243 */ 244 cinit() 245 { 246 register int ccp; 247 register struct cblock *cp; 248 register struct cdevsw *cdp; 249 250 ccp = (int)cfree; 251 ccp = (ccp+CROUND) & ~CROUND; 252 for(cp=(struct cblock *)ccp; cp < &cfree[nclist-1]; cp++) { 253 cp->c_next = cfreelist; 254 cfreelist = cp; 255 cfreecount += CBSIZE; 256 } 257 ccp = 0; 258 for(cdp = cdevsw; cdp->d_open; cdp++) 259 ccp++; 260 nchrdev = ccp; 261 } 262