bsd/dev/ppc/systemcalls.c

   1 /*
   2  * Copyright (c) 2000-2003 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25
  26 #include <kern/task.h>
  27 #include <kern/thread.h>
  28 #include <kern/thread_act.h>
  29 #include <kern/assert.h>
  30 #include <kern/clock.h>
  31 #include <mach/machine/thread_status.h>
  32 #include <ppc/savearea.h>
  33
  34 #include <sys/kernel.h>
  35 #include <sys/vm.h>
  36 #include <sys/proc.h>
  37 #include <sys/syscall.h>
  38 #include <sys/systm.h>
  39 #include <sys/user.h>
  40 #include <sys/errno.h>
  41 #include <sys/ktrace.h>
  42 #include <sys/kdebug.h>
  43 #include <sys/kern_audit.h>
  44
  45 extern void
  46 unix_syscall(
  47         struct savearea *regs
  48 );
  49
  50 extern struct savearea *
  51 find_user_regs(
  52         thread_act_t act);
  53
  54 extern void enter_funnel_section(funnel_t *funnel_lock);
  55 extern void exit_funnel_section(void);
  56
  57 /*
  58  * Function:    unix_syscall
  59  *
  60  * Inputs:      regs    - pointer to Process Control Block
  61  *
  62  * Outputs:     none
  63  */
  64 void
  65 unix_syscall(
  66         struct savearea *regs
  67 )
  68 {
  69         thread_act_t            thread_act;
  70         struct uthread          *uthread;
  71         struct proc                     *proc;
  72         struct sysent           *callp;
  73         int                                     error;
  74         unsigned short          code;
  75         boolean_t                       flavor;
  76         int funnel_type;
  77
  78         flavor = (((unsigned int)regs->save_r0) == NULL)? 1: 0;
  79
  80         if (flavor)
  81                 code = regs->save_r3;
  82         else
  83                 code = regs->save_r0;
  84
  85         if (kdebug_enable && (code != 180)) {
  86                 if (flavor)
  87                         KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_EXCP_SC, code) | DBG_FUNC_START,
  88                                 regs->save_r4, regs->save_r5, regs->save_r6, regs->save_r7, 0);
  89                 else
  90                         KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_EXCP_SC, code) | DBG_FUNC_START,
  91                                 regs->save_r3, regs->save_r4, regs->save_r5, regs->save_r6, 0);
  92         }
  93         thread_act = current_act();
  94         uthread = get_bsdthread_info(thread_act);
  95
  96         if (!(uthread->uu_flag & P_VFORK))
  97                 proc = (struct proc *)get_bsdtask_info(current_task());
  98         else
  99                 proc = current_proc();
 100
 101         uthread->uu_ar0 = (int *)regs;
 102
 103         callp = (code >= nsysent) ? &sysent[63] : &sysent[code];
 104
 105 #ifdef  DEBUG
 106         if (callp->sy_narg > 8)
 107                 panic("unix_syscall: max arg count exceeded");
 108 #endif
 109
 110         if (callp->sy_narg != 0) {
 111                 if ( !flavor) {
 112                         uthread->uu_arg[0] = regs->save_r3;
 113                         uthread->uu_arg[1] = regs->save_r4;
 114                         uthread->uu_arg[2] = regs->save_r5;
 115                         uthread->uu_arg[3] = regs->save_r6;
 116                         uthread->uu_arg[4] = regs->save_r7;
 117                         uthread->uu_arg[5] = regs->save_r8;
 118                         uthread->uu_arg[6] = regs->save_r9;
 119                         uthread->uu_arg[7] = regs->save_r10;
 120                 } else {
 121                         uthread->uu_arg[0] = regs->save_r4;
 122                         uthread->uu_arg[1] = regs->save_r5;
 123                         uthread->uu_arg[2] = regs->save_r6;
 124                         uthread->uu_arg[3] = regs->save_r7;
 125                         uthread->uu_arg[4] = regs->save_r8;
 126                         uthread->uu_arg[5] = regs->save_r9;
 127                         uthread->uu_arg[7] = regs->save_r10;
 128                 }
 129         }
 130
 131         funnel_type = (int)callp->sy_funnel;
 132         if (funnel_type == KERNEL_FUNNEL)
 133                  enter_funnel_section(kernel_flock);
 134         else if (funnel_type == NETWORK_FUNNEL)
 135                  enter_funnel_section(network_flock);
 136
 137         uthread->uu_rval[0] = 0;
 138
 139         /*
 140          * r4 is volatile, if we set it to regs->save_r4 here the child
 141          * will have parents r4 after execve
 142          */
 143         uthread->uu_rval[1] = 0;
 144
 145         error = 0;
 146
 147         /*
 148          * PPC runtime calls cerror after every unix system call, so
 149          * assume no error and adjust the "pc" to skip this call.
 150          * It will be set back to the cerror call if an error is detected.
 151          */
 152         regs->save_srr0 += 4;
 153
 154         if (KTRPOINT(proc, KTR_SYSCALL))
 155                 ktrsyscall(proc, code, callp->sy_narg, uthread->uu_arg, funnel_type);
 156
 157         AUDIT_CMD(audit_syscall_enter(code, proc, uthread));
 158         error = (*(callp->sy_call))(proc, (void *)uthread->uu_arg, &(uthread->uu_rval[0]));
 159         AUDIT_CMD(audit_syscall_exit(error, proc, uthread));
 160
 161         regs = find_user_regs(thread_act);
 162
 163         if (error == ERESTART) {
 164                 regs->save_srr0 -= 8;
 165         } else if (error != EJUSTRETURN) {
 166                 if (error) {
 167                         regs->save_r3 = (long long)error;
 168                         /* set the "pc" to execute cerror routine */
 169                         regs->save_srr0 -= 4;
 170                 } else { /* (not error) */
 171                         regs->save_r3 = uthread->uu_rval[0];
 172                         regs->save_r4 = uthread->uu_rval[1];
 173                 }
 174         }
 175         /* else  (error == EJUSTRETURN) { nothing } */
 176
 177         if (KTRPOINT(proc, KTR_SYSRET))
 178                 ktrsysret(proc, code, error, uthread->uu_rval[0], funnel_type);
 179
 180          exit_funnel_section();
 181
 182         if (kdebug_enable && (code != 180)) {
 183                 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_EXCP_SC, code) | DBG_FUNC_END,
 184                         error, uthread->uu_rval[0], uthread->uu_rval[1], 0, 0);
 185         }
 186
 187         thread_exception_return();
 188         /* NOTREACHED */
 189 }
 190
 191 unix_syscall_return(error)
 192 {
 193         thread_act_t                            thread_act;
 194         struct uthread                          *uthread;
 195         struct proc                                     *proc;
 196         struct savearea                         *regs;
 197         unsigned short                          code;
 198         struct sysent                           *callp;
 199         int funnel_type;
 200
 201         thread_act = current_act();
 202         proc = current_proc();
 203         uthread = get_bsdthread_info(thread_act);
 204
 205         regs = find_user_regs(thread_act);
 206
 207         /*
 208          * Get index into sysent table
 209          */
 210         if (error == ERESTART) {
 211                 regs->save_srr0 -= 8;
 212         } else if (error != EJUSTRETURN) {
 213                 if (error) {
 214                         regs->save_r3 = (long long)error;
 215                         /* set the "pc" to execute cerror routine */
 216                         regs->save_srr0 -= 4;
 217                 } else { /* (not error) */
 218                         regs->save_r3 = uthread->uu_rval[0];
 219                         regs->save_r4 = uthread->uu_rval[1];
 220                 }
 221         }
 222         /* else  (error == EJUSTRETURN) { nothing } */
 223
 224         if (regs->save_r0 != NULL)
 225                 code = regs->save_r0;
 226         else
 227                 code = regs->save_r3;
 228
 229         callp = (code >= nsysent) ? &sysent[63] : &sysent[code];
 230
 231         funnel_type = (int)callp->sy_funnel;
 232
 233         if (KTRPOINT(proc, KTR_SYSRET))
 234                 ktrsysret(proc, code, error, uthread->uu_rval[0], funnel_type);
 235
 236          exit_funnel_section();
 237
 238         if (kdebug_enable && (code != 180)) {
 239                 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_EXCP_SC, code) | DBG_FUNC_END,
 240                         error, uthread->uu_rval[0], uthread->uu_rval[1], 0, 0);
 241         }
 242
 243         thread_exception_return();
 244         /* NOTREACHED */
 245 }
 246
 247 /*
 248  * Time of day and interval timer support.
 249  *
 250  * These routines provide the kernel entry points to get and set
 251  * the time-of-day and per-process interval timers.  Subroutines
 252  * here provide support for adding and subtracting timeval structures
 253  * and decrementing interval timers, optionally reloading the interval
 254  * timers when they expire.
 255  */
 256 struct gettimeofday_args{
 257         struct timeval *tp;
 258         struct timezone *tzp;
 259 };
 260 /*  NOTE THIS implementation is for  ppc architectures only.
 261  *  It is infrequently called, since the commpage intercepts
 262  *  most calls in user mode.
 263  */
 264 int
 265 ppc_gettimeofday(p, uap, retval)
 266         struct proc *p;
 267         register struct gettimeofday_args *uap;
 268         register_t *retval;
 269 {
 270         int error = 0;
 271
 272         if (uap->tp)
 273                 clock_gettimeofday(&retval[0], &retval[1]);
 274
 275         if (uap->tzp) {
 276                 struct timezone ltz;
 277                 extern simple_lock_data_t tz_slock;
 278
 279                 usimple_lock(&tz_slock);
 280                 ltz = tz;
 281                 usimple_unlock(&tz_slock);
 282                 error = copyout((caddr_t)&ltz, (caddr_t)uap->tzp, sizeof (tz));
 283         }
 284
 285         return (error);
 286 }
 287