arch/parisc/hpux/wrappers.S

   1 /*
   2  * Linux/PARISC Project (http://www.parisc-linux.org/)
   3  *
   4  * HP-UX System Call Wrapper routines and System Call Return Path
   5  *
   6  * Copyright (C) 2000 Hewlett-Packard (John Marvin)
   7  *
   8  *    This program is free software; you can redistribute it and/or modify
   9  *    it under the terms of the GNU General Public License as published by
  10  *    the Free Software Foundation; either version 2, or (at your option)
  11  *    any later version.
  12  *
  13  *    This program is distributed in the hope that it will be useful,
  14  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *    GNU General Public License for more details.
  17  *
  18  *    You should have received a copy of the GNU General Public License
  19  *    along with this program; if not, write to the Free Software
  20  *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21  */
  22
  23 #ifdef __LP64__
  24 #warning PA64 support needs more work...did first cut
  25 #endif
  26
  27 #include <asm/offsets.h>
  28 #include <asm/assembly.h>
  29 #include <asm/signal.h>
  30
  31 #ifdef __LP64__
  32         .level          2.0w
  33 #else
  34         .level          1.1
  35 #endif
  36         .text
  37
  38         /* These should probably go in a header file somewhere.
  39          * They are duplicated in kernel/wrappers.S
  40          * Possibly we should consider consolidating these
  41          * register save/restore macros.
  42          */
  43         .macro  reg_save regs
  44 #ifdef __LP64__
  45 #warning NEEDS WORK for 64-bit
  46 #endif
  47         STREG   %r3, PT_GR3(\regs)
  48         STREG   %r4, PT_GR4(\regs)
  49         STREG   %r5, PT_GR5(\regs)
  50         STREG   %r6, PT_GR6(\regs)
  51         STREG   %r7, PT_GR7(\regs)
  52         STREG   %r8, PT_GR8(\regs)
  53         STREG   %r9, PT_GR9(\regs)
  54         STREG   %r10,PT_GR10(\regs)
  55         STREG   %r11,PT_GR11(\regs)
  56         STREG   %r12,PT_GR12(\regs)
  57         STREG   %r13,PT_GR13(\regs)
  58         STREG   %r14,PT_GR14(\regs)
  59         STREG   %r15,PT_GR15(\regs)
  60         STREG   %r16,PT_GR16(\regs)
  61         STREG   %r17,PT_GR17(\regs)
  62         STREG   %r18,PT_GR18(\regs)
  63         .endm
  64
  65         .macro  reg_restore regs
  66         LDREG   PT_GR3(\regs), %r3
  67         LDREG   PT_GR4(\regs), %r4
  68         LDREG   PT_GR5(\regs), %r5
  69         LDREG   PT_GR6(\regs), %r6
  70         LDREG   PT_GR7(\regs), %r7
  71         LDREG   PT_GR8(\regs), %r8
  72         LDREG   PT_GR9(\regs), %r9
  73         LDREG   PT_GR10(\regs),%r10
  74         LDREG   PT_GR11(\regs),%r11
  75         LDREG   PT_GR12(\regs),%r12
  76         LDREG   PT_GR13(\regs),%r13
  77         LDREG   PT_GR14(\regs),%r14
  78         LDREG   PT_GR15(\regs),%r15
  79         LDREG   PT_GR16(\regs),%r16
  80         LDREG   PT_GR17(\regs),%r17
  81         LDREG   PT_GR18(\regs),%r18
  82         .endm
  83
  84
  85         .export hpux_fork_wrapper
  86         .export hpux_child_return
  87         .import sys_fork
  88
  89 hpux_fork_wrapper:
  90         ldo     TASK_REGS-TASK_SZ_ALGN-64(%r30),%r1         ;! get pt regs
  91                                                             ;! pointer in task
  92         reg_save %r1
  93
  94         STREG   %r2,-20(%r30)
  95         ldo     64(%r30),%r30
  96         STREG   %r2,PT_GR19(%r1)        ;! save for child
  97         STREG   %r30,PT_GR21(%r1)       ;! save for child
  98
  99         LDREG   PT_GR30(%r1),%r25
 100         mtctl   %r25,%cr29
 101         copy    %r1,%r24
 102         bl      sys_clone,%r2
 103         ldi     SIGCHLD,%r26
 104
 105         LDREG   -84(%r30),%r2
 106 fork_return:
 107         ldo     -64(%r30),%r30
 108         ldo     TASK_REGS-TASK_SZ_ALGN-64(%r30),%r1         ;! get pt regs
 109
 110         reg_restore %r1
 111
 112         /*
 113          * HP-UX wants pid (child gets parent pid, parent gets child pid)
 114          * in r28 and a flag in r29 (r29 == 1 for child, 0 for parent).
 115          * Linux fork returns 0 for child, pid for parent. Since HP-UX
 116          * libc stub throws away parent pid and returns 0 for child,
 117          * we'll just return 0 for parent pid now. Only applications
 118          * that jump directly to the gateway page (not supported) will
 119          * know the difference. We can fix this later if necessary.
 120          */
 121
 122         ldo     -1024(%r0),%r1
 123         comb,>>=,n %r28,%r1,fork_exit  /* just let the syscall exit handle it */
 124         or,=    %r28,%r0,%r0
 125         or,tr   %r0,%r0,%r29    /* r28 <> 0, we are parent, set r29 to 0 */
 126         ldo     1(%r0),%r29     /* r28 == 0, we are child,  set r29 to 1 */
 127
 128 fork_exit:
 129         bv      %r0(%r2)
 130         nop
 131
 132         /* Set the return value for the child */
 133
 134 hpux_child_return:
 135 #if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT)
 136         bl      schedule_tail, %r2
 137         nop
 138 #endif
 139
 140         LDREG   TASK_PT_GR19-TASK_SZ_ALGN-128(%r30),%r2
 141         b fork_return
 142         copy %r0,%r28
 143
 144         .export hpux_execve_wrapper
 145         .export hpux_execv_wrapper
 146         .import hpux_execve
 147
 148 hpux_execv_wrapper:
 149         copy %r0,%r24  /* NULL environment */
 150
 151 hpux_execve_wrapper:
 152
 153         ldo     TASK_REGS-TASK_SZ_ALGN-64(%r30),%r1         ;! get pt regs
 154
 155         /*
 156          * Do we need to save/restore r3-r18 here?
 157          * I don't think so. why would new thread need old
 158          * threads registers?
 159          */
 160
 161         /* Store arg0, arg1 and arg2 so that hpux_execve will find them */
 162
 163         STREG %r26,PT_GR26(%r1)
 164         STREG %r25,PT_GR25(%r1)
 165         STREG %r24,PT_GR24(%r1)
 166
 167         STREG %r2,-20(%r30)
 168         ldo 64(%r30),%r30
 169         bl hpux_execve,%r2
 170         copy %r1,%arg0
 171
 172         ldo -64(%r30),%r30
 173         LDREG   -20(%r30),%r2
 174
 175         /* If exec succeeded we need to load the args */
 176
 177         ldo -1024(%r0),%r1
 178         comb,>>= %r28,%r1,exec_error
 179         copy %r2,%r19
 180         ldo     -TASK_SZ_ALGN-64(%r30),%r1         ;! get task ptr
 181         LDREG   TASK_PT_GR26(%r1),%r26
 182         LDREG   TASK_PT_GR25(%r1),%r25
 183         LDREG   TASK_PT_GR24(%r1),%r24
 184         LDREG   TASK_PT_GR23(%r1),%r23
 185         copy %r0,%r2    /* Flag to syscall_exit not to clear args */
 186
 187 exec_error:
 188         bv %r0(%r19)
 189         nop
 190
 191         .export hpux_pipe_wrapper
 192         .import hpux_pipe
 193
 194         /* HP-UX expects pipefd's returned in r28 & r29 */
 195
 196 hpux_pipe_wrapper:
 197         STREG %r2,-20(%r30)
 198         ldo 64(%r30),%r30
 199         bl hpux_pipe,%r2
 200         ldo -56(%r30),%r26 /* pass local array to hpux_pipe */
 201
 202
 203         ldo -1024(%r0),%r1
 204         comb,>>= %r28,%r1,pipe_exit /* let syscall exit handle it */
 205         LDREG   -84(%r30),%r2
 206
 207         /* if success, load fd's from stack array */
 208
 209         LDREG   -56(%r30),%r28
 210         LDREG   -52(%r30),%r29
 211
 212 pipe_exit:
 213         bv %r0(%r2)
 214         ldo -64(%r30),%r30
 215
 216         .export hpux_syscall_exit
 217         .import syscall_exit
 218
 219 hpux_syscall_exit:
 220
 221         /*
 222          *
 223          * HP-UX call return conventions:
 224          *
 225          * if error:
 226          *       r22 = 1
 227          *       r28 = errno value
 228          *       r29 = secondary return value
 229          * else
 230          *       r22 = 0
 231          *       r28 = return value
 232          *       r29 = secondary return value
 233          *
 234          * For now, we'll just check to see if r28 is < (unsigned long)-1024
 235          * (to handle addresses > 2 Gb) and if so set r22 to zero. If not,
 236          * we'll complement r28 and set r22 to 1. Wrappers will be
 237          * needed for syscalls that care about the secondary return value.
 238          * The wrapper may also need a way of avoiding the following code,
 239          * but we'll deal with that when it becomes necessary.
 240          */
 241
 242         ldo -1024(%r0),%r1
 243         comb,<< %r28,%r1,no_error
 244         copy %r0,%r22
 245         subi 0,%r28,%r28
 246         ldo 1(%r0),%r22
 247
 248 no_error:
 249         b syscall_exit
 250         nop
 251
 252         .export hpux_unimplemented_wrapper
 253         .import hpux_unimplemented
 254
 255 hpux_unimplemented_wrapper:
 256         b hpux_unimplemented
 257         STREG %r22,-64(%r30)  /* overwrite arg8 with syscall number */