1 /* init_main.c 3.13 09/16/80 */ 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 44 cpusid = mfpr(SID); /* get system identification */ 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 56 proc[0].p_p0br = (struct pte *)mfpr(P0BR); 57 proc[0].p_szpt = 1; 58 proc[0].p_addr = uaddr(&proc[0]); 59 proc[0].p_stat = SRUN; 60 proc[0].p_flag |= SLOAD|SSYS; 61 proc[0].p_nice = NZERO; 62 u.u_procp = &proc[0]; 63 u.u_cmask = CMASK; 64 for (i = 1; i < sizeof(u.u_limit)/sizeof(u.u_limit[0]); i++) 65 switch (i) { 66 67 case LIM_STACK: 68 u.u_limit[i] = 512*1024; 69 continue; 70 case LIM_DATA: 71 u.u_limit[i] = ctob(MAXDSIZ); 72 continue; 73 default: 74 u.u_limit[i] = INFINITY; 75 continue; 76 } 77 clkstart(); 78 79 /* 80 * Initialize devices and 81 * set up 'known' i-nodes 82 */ 83 84 ihinit(); 85 bhinit(); 86 cinit(); 87 binit(); 88 bswinit(); 89 iinit(); 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 * make page-out daemon (process 2) 100 * the daemon has ctopt(NSWBUF*CLSIZE*KLMAX) pages of page 101 * table so that it can map dirty pages into 102 * its address space during asychronous pushes. 103 */ 104 105 mpid = 1; 106 proc[0].p_szpt = clrnd(ctopt(NSWBUF*CLSIZE*KLMAX + UPAGES)); 107 proc[1].p_stat = SZOMB; /* force it to be in proc slot 2 */ 108 if (newproc(0)) { 109 proc[2].p_flag |= SLOAD|SSYS; 110 proc[2].p_dsize = u.u_dsize = NSWBUF*CLSIZE*KLMAX; 111 pageout(); 112 } 113 114 /* 115 * make init process and 116 * enter scheduling loop 117 */ 118 119 mpid = 0; 120 proc[1].p_stat = 0; 121 proc[0].p_szpt = CLSIZE; 122 if (newproc(0)) { 123 expand(clrnd((int)btoc(szicode)), P0BR); 124 swpexpand(u.u_dsize, 0, &u.u_dmap, &u.u_smap); 125 (void) copyout((caddr_t)icode, (caddr_t)0, (unsigned)szicode); 126 /* 127 * Return goes to loc. 0 of user init 128 * code just copied out. 129 */ 130 return; 131 } 132 proc[0].p_szpt = 1; 133 sched(); 134 } 135 136 /* 137 * iinit is called once (from main) 138 * very early in initialization. 139 * It reads the root's super block 140 * and initializes the current date 141 * from the last modified date. 142 * 143 * panic: iinit -- cannot read the super 144 * block. Usually because of an IO error. 145 */ 146 iinit() 147 { 148 register struct buf *cp, *bp; 149 register struct filsys *fp; 150 151 (*bdevsw[major(rootdev)].d_open)(rootdev, 1); 152 bp = bread(rootdev, SUPERB); 153 cp = geteblk(); 154 if(u.u_error) 155 panic("iinit"); 156 bcopy(bp->b_un.b_addr, cp->b_un.b_addr, sizeof(struct filsys)); 157 brelse(bp); 158 mount[0].m_bufp = cp; 159 mount[0].m_dev = rootdev; 160 fp = cp->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 bfreelist.b_forw = bfreelist.b_back = 196 bfreelist.av_forw = bfreelist.av_back = &bfreelist; 197 for (i=0; i<NBUF; i++) { 198 bp = &buf[i]; 199 bp->b_dev = NODEV; 200 bp->b_un.b_addr = buffers[i]; 201 bp->b_back = &bfreelist; 202 bp->b_forw = bfreelist.b_forw; 203 bfreelist.b_forw->b_back = bp; 204 bfreelist.b_forw = bp; 205 bp->b_flags = B_BUSY; 206 brelse(bp); 207 } 208 for (bdp = bdevsw; bdp->d_open; bdp++) { 209 dp = bdp->d_tab; 210 if(dp) { 211 dp->b_forw = dp; 212 dp->b_back = dp; 213 } 214 nblkdev++; 215 } 216 /* 217 * Count swap devices, and adjust total swap space available. 218 * Some of this space will not be available until a vswapon() 219 * system is issued, usually when the system goes multi-user. 220 */ 221 nswdev = 0; 222 for (swp = swdevt; swp->sw_dev; swp++) 223 nswdev++; 224 if (nswdev == 0) 225 panic("binit"); 226 nswap *= nswdev; 227 maxpgio *= nswdev; 228 swfree(0); 229 } 230 231 /* 232 * Initialize linked list of free swap 233 * headers. These do not actually point 234 * to buffers, but rather to pages that 235 * are being swapped in and out. 236 */ 237 bswinit() 238 { 239 register int i; 240 241 bswlist.av_forw = &swbuf[0]; 242 for (i=0; i<NSWBUF-1; i++) 243 swbuf[i].av_forw = &swbuf[i+1]; 244 swbuf[NSWBUF-1].av_forw = NULL; 245 } 246