arch/um/kernel/skas/mem_user.c

   1 /*
   2  * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include <signal.h>
   7 #include <errno.h>
   8 #include <sys/mman.h>
   9 #include <sys/wait.h>
  10 #include <asm/page.h>
  11 #include <asm/unistd.h>
  12 #include "mem_user.h"
  13 #include "mem.h"
  14 #include "mm_id.h"
  15 #include "user.h"
  16 #include "os.h"
  17 #include "proc_mm.h"
  18 #include "ptrace_user.h"
  19 #include "user_util.h"
  20 #include "kern_util.h"
  21 #include "task.h"
  22 #include "registers.h"
  23 #include "uml-config.h"
  24 #include "sysdep/ptrace.h"
  25 #include "sysdep/stub.h"
  26 #include "skas.h"
  27
  28 extern unsigned long syscall_stub, __syscall_stub_start;
  29
  30 extern void wait_stub_done(int pid, int sig, char * fname);
  31
  32 static long run_syscall_stub(struct mm_id * mm_idp, int syscall,
  33                              unsigned long *args)
  34 {
  35         int n, pid = mm_idp->u.pid;
  36         unsigned long regs[MAX_REG_NR];
  37
  38         get_safe_registers(regs);
  39         regs[REGS_IP_INDEX] = UML_CONFIG_STUB_CODE +
  40                 ((unsigned long) &syscall_stub -
  41                  (unsigned long) &__syscall_stub_start);
  42         /* XXX Don't have a define for starting a syscall */
  43         regs[REGS_SYSCALL_NR] = syscall;
  44         regs[REGS_SYSCALL_ARG1] = args[0];
  45         regs[REGS_SYSCALL_ARG2] = args[1];
  46         regs[REGS_SYSCALL_ARG3] = args[2];
  47         regs[REGS_SYSCALL_ARG4] = args[3];
  48         regs[REGS_SYSCALL_ARG5] = args[4];
  49         regs[REGS_SYSCALL_ARG6] = args[5];
  50         n = ptrace_setregs(pid, regs);
  51         if(n < 0){
  52                 printk("run_syscall_stub : PTRACE_SETREGS failed, "
  53                        "errno = %d\n", n);
  54                 return(n);
  55         }
  56
  57         wait_stub_done(pid, 0, "run_syscall_stub");
  58
  59         return(*((unsigned long *) mm_idp->stack));
  60 }
  61
  62 int map(struct mm_id *mm_idp, unsigned long virt, unsigned long len,
  63         int r, int w, int x, int phys_fd, unsigned long long offset)
  64 {
  65         int prot, n;
  66
  67         prot = (r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) |
  68                 (x ? PROT_EXEC : 0);
  69
  70         if(proc_mm){
  71                 struct proc_mm_op map;
  72                 int fd = mm_idp->u.mm_fd;
  73                 map = ((struct proc_mm_op) { .op        = MM_MMAP,
  74                                              .u         =
  75                                              { .mmap    =
  76                                                { .addr  = virt,
  77                                                  .len   = len,
  78                                                  .prot  = prot,
  79                                                  .flags = MAP_SHARED |
  80                                                  MAP_FIXED,
  81                                                  .fd    = phys_fd,
  82                                                  .offset= offset
  83                                                } } } );
  84                 n = os_write_file(fd, &map, sizeof(map));
  85                 if(n != sizeof(map))
  86                         printk("map : /proc/mm map failed, err = %d\n", -n);
  87         }
  88         else {
  89                 long res;
  90                 unsigned long args[] = { virt, len, prot,
  91                                          MAP_SHARED | MAP_FIXED, phys_fd,
  92                                          MMAP_OFFSET(offset) };
  93
  94                 res = run_syscall_stub(mm_idp, STUB_MMAP_NR, args);
  95                 if((void *) res == MAP_FAILED)
  96                         printk("mmap stub failed, errno = %d\n", res);
  97         }
  98
  99         return 0;
 100 }
 101
 102 int unmap(struct mm_id *mm_idp, void *addr, unsigned long len)
 103 {
 104         int n;
 105
 106         if(proc_mm){
 107                 struct proc_mm_op unmap;
 108                 int fd = mm_idp->u.mm_fd;
 109                 unmap = ((struct proc_mm_op) { .op      = MM_MUNMAP,
 110                                                .u       =
 111                                                { .munmap        =
 112                                                  { .addr        =
 113                                                    (unsigned long) addr,
 114                                                    .len         = len } } } );
 115                 n = os_write_file(fd, &unmap, sizeof(unmap));
 116                 if(n != sizeof(unmap)) {
 117                         if(n < 0)
 118                                 return(n);
 119                         else if(n > 0)
 120                                 return(-EIO);
 121                 }
 122         }
 123         else {
 124                 int res;
 125                 unsigned long args[] = { (unsigned long) addr, len, 0, 0, 0,
 126                                          0 };
 127
 128                 res = run_syscall_stub(mm_idp, __NR_munmap, args);
 129                 if(res < 0)
 130                         printk("munmap stub failed, errno = %d\n", res);
 131         }
 132
 133         return(0);
 134 }
 135
 136 int protect(struct mm_id *mm_idp, unsigned long addr, unsigned long len,
 137             int r, int w, int x)
 138 {
 139         struct proc_mm_op protect;
 140         int prot, n;
 141
 142         prot = (r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) |
 143                 (x ? PROT_EXEC : 0);
 144
 145         if(proc_mm){
 146                 int fd = mm_idp->u.mm_fd;
 147                 protect = ((struct proc_mm_op) { .op    = MM_MPROTECT,
 148                                                  .u     =
 149                                                  { .mprotect    =
 150                                                    { .addr      =
 151                                                      (unsigned long) addr,
 152                                                      .len       = len,
 153                                                      .prot      = prot } } } );
 154
 155                 n = os_write_file(fd, &protect, sizeof(protect));
 156                 if(n != sizeof(protect))
 157                         panic("protect failed, err = %d", -n);
 158         }
 159         else {
 160                 int res;
 161                 unsigned long args[] = { addr, len, prot, 0, 0, 0 };
 162
 163                 res = run_syscall_stub(mm_idp, __NR_mprotect, args);
 164                 if(res < 0)
 165                         panic("mprotect stub failed, errno = %d\n", res);
 166         }
 167
 168         return(0);
 169 }
 170
 171 void before_mem_skas(unsigned long unused)
 172 {
 173 }