1 /* 2 * Copyright (c) 1982, 1986, 1989 Regents of the University of California. 3 * All rights reserved. The Berkeley software License Agreement 4 * specifies the terms and conditions for redistribution. 5 * 6 * @(#)sys_process.c 7.14 (Berkeley) 12/05/90 7 */ 8 9 #define IPCREG 10 #include "param.h" 11 #include "user.h" 12 #include "proc.h" 13 #include "vnode.h" 14 #include "seg.h" 15 #include "buf.h" 16 #include "ptrace.h" 17 18 #include "machine/reg.h" 19 #include "machine/psl.h" 20 #include "../vm/vm_page.h" 21 #include "../vm/vm_prot.h" 22 23 /* 24 * Priority for tracing 25 */ 26 #define IPCPRI PZERO 27 28 /* 29 * Tracing variables. 30 * Used to pass trace command from 31 * parent to child being traced. 32 * This data base cannot be 33 * shared and is locked 34 * per user. 35 */ 36 struct { 37 int ip_lock; 38 int ip_req; 39 int *ip_addr; 40 int ip_data; 41 } ipc; 42 43 /* 44 * sys-trace system call. 45 */ 46 ptrace(curp, uap, retval) 47 struct proc *curp; 48 register struct args { 49 int req; 50 int pid; 51 int *addr; 52 int data; 53 } *uap; 54 int *retval; 55 { 56 register struct proc *p; 57 58 if (uap->req <= 0) { 59 curp->p_flag |= STRC; 60 return (0); 61 } 62 p = pfind(uap->pid); 63 if (p == 0 || p->p_stat != SSTOP || p->p_ppid != curp->p_pid || 64 !(p->p_flag & STRC)) 65 return (ESRCH); 66 while (ipc.ip_lock) 67 sleep((caddr_t)&ipc, IPCPRI); 68 ipc.ip_lock = p->p_pid; 69 ipc.ip_data = uap->data; 70 ipc.ip_addr = uap->addr; 71 ipc.ip_req = uap->req; 72 p->p_flag &= ~SWTED; 73 while (ipc.ip_req > 0) { 74 if (p->p_stat==SSTOP) 75 setrun(p); 76 sleep((caddr_t)&ipc, IPCPRI); 77 } 78 *retval = ipc.ip_data; 79 ipc.ip_lock = 0; 80 wakeup((caddr_t)&ipc); 81 if (ipc.ip_req < 0) 82 return (EIO); 83 return (0); 84 } 85 86 #define PHYSOFF(p, o) \ 87 ((physadr)(p)+((o)/sizeof(((physadr)0)->r[0]))) 88 89 /* 90 * Code that the child process 91 * executes to implement the command 92 * of the parent process in tracing. 93 */ 94 procxmt(p) 95 register struct proc *p; 96 { 97 register int i, *poff; 98 99 if (ipc.ip_lock != p->p_pid) 100 return (0); 101 p->p_slptime = 0; 102 i = ipc.ip_req; 103 ipc.ip_req = 0; 104 switch (i) { 105 106 case PT_READ_I: /* read the child's text space */ 107 if (!useracc((caddr_t)ipc.ip_addr, 4, B_READ)) 108 goto error; 109 ipc.ip_data = fuiword((caddr_t)ipc.ip_addr); 110 break; 111 112 case PT_READ_D: /* read the child's data space */ 113 if (!useracc((caddr_t)ipc.ip_addr, 4, B_READ)) 114 goto error; 115 ipc.ip_data = fuword((caddr_t)ipc.ip_addr); 116 break; 117 118 case PT_READ_U: /* read the child's u. */ 119 #ifdef HPUXCOMPAT 120 if (u.u_pcb.pcb_flags & PCB_HPUXTRACE) 121 i = hpuxtobsduoff(ipc.ip_addr); 122 else 123 #endif 124 i = (int)ipc.ip_addr; 125 if (i<0 || i > ctob(UPAGES)-sizeof(int)) 126 goto error; 127 ipc.ip_data = *(int *)PHYSOFF(&u, i); 128 break; 129 130 case PT_WRITE_I: /* write the child's text space */ 131 if ((i = suiword((caddr_t)ipc.ip_addr, ipc.ip_data)) < 0) { 132 vm_offset_t sa, ea; 133 int rv; 134 135 sa = trunc_page((vm_offset_t)ipc.ip_addr); 136 ea = round_page((vm_offset_t)ipc.ip_addr+sizeof(int)-1); 137 rv = vm_map_protect(p->p_map, sa, ea, 138 VM_PROT_DEFAULT, FALSE); 139 if (rv == KERN_SUCCESS) { 140 i = suiword((caddr_t)ipc.ip_addr, ipc.ip_data); 141 (void) vm_map_protect(p->p_map, sa, ea, 142 VM_PROT_READ|VM_PROT_EXECUTE, FALSE); 143 } 144 } 145 if (i < 0) 146 goto error; 147 break; 148 149 case PT_WRITE_D: /* write the child's data space */ 150 if (suword((caddr_t)ipc.ip_addr, 0) < 0) 151 goto error; 152 (void) suword((caddr_t)ipc.ip_addr, ipc.ip_data); 153 break; 154 155 case PT_WRITE_U: /* write the child's u. */ 156 #ifdef HPUXCOMPAT 157 if (u.u_pcb.pcb_flags & PCB_HPUXTRACE) 158 i = hpuxtobsduoff(ipc.ip_addr); 159 else 160 #endif 161 i = (int)ipc.ip_addr; 162 poff = (int *)PHYSOFF(&u, i); 163 for (i=0; i<NIPCREG; i++) 164 if (poff == &u.u_ar0[ipcreg[i]]) 165 goto ok; 166 if (poff == &u.u_ar0[PS]) { 167 ipc.ip_data |= PSL_USERSET; 168 ipc.ip_data &= ~PSL_USERCLR; 169 #ifdef PSL_CM_CLR 170 if (ipc.ip_data & PSL_CM) 171 ipc.ip_data &= ~PSL_CM_CLR; 172 #endif 173 goto ok; 174 } 175 #if defined(hp300) 176 #ifdef FPCOPROC 177 if (poff >= (int *)u.u_pcb.pcb_fpregs.fpf_regs && 178 poff <= (int *)&u.u_pcb.pcb_fpregs.fpf_fpiar) 179 goto ok; 180 #endif 181 #endif 182 goto error; 183 184 ok: 185 *poff = ipc.ip_data; 186 break; 187 188 case PT_STEP: /* single step the child */ 189 case PT_CONTINUE: /* continue the child */ 190 if ((int)ipc.ip_addr != 1) 191 u.u_ar0[PC] = (int)ipc.ip_addr; 192 if ((unsigned)ipc.ip_data > NSIG) 193 goto error; 194 p->p_xstat = ipc.ip_data; /* see issig */ 195 if (i == PT_STEP) 196 u.u_ar0[PS] |= PSL_T; 197 wakeup((caddr_t)&ipc); 198 return (1); 199 200 case PT_KILL: /* kill the child process */ 201 wakeup((caddr_t)&ipc); 202 exit(p, (int)p->p_xstat); 203 204 default: 205 error: 206 ipc.ip_req = -1; 207 } 208 wakeup((caddr_t)&ipc); 209 return (0); 210 } 211