arch/um/sys-i386/syscalls.c

   1 /*
   2  * Copyright (C) 2000 - 2003 Jeff Dike (jdike@addtoit.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include "linux/sched.h"
   7 #include "linux/shm.h"
   8 #include "asm/ipc.h"
   9 #include "asm/mman.h"
  10 #include "asm/uaccess.h"
  11 #include "asm/unistd.h"
  12
  13 /*
  14  * Perform the select(nd, in, out, ex, tv) and mmap() system
  15  * calls. Linux/i386 didn't use to be able to handle more than
  16  * 4 system call parameters, so these system calls used a memory
  17  * block for parameter passing..
  18  */
  19
  20 struct mmap_arg_struct {
  21         unsigned long addr;
  22         unsigned long len;
  23         unsigned long prot;
  24         unsigned long flags;
  25         unsigned long fd;
  26         unsigned long offset;
  27 };
  28
  29 extern int old_mmap(unsigned long addr, unsigned long len,
  30                     unsigned long prot, unsigned long flags,
  31                     unsigned long fd, unsigned long offset);
  32
  33 long old_mmap_i386(struct mmap_arg_struct __user *arg)
  34 {
  35         struct mmap_arg_struct a;
  36         int err = -EFAULT;
  37
  38         if (copy_from_user(&a, arg, sizeof(a)))
  39                 goto out;
  40
  41         err = old_mmap(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
  42  out:
  43         return err;
  44 }
  45
  46 struct sel_arg_struct {
  47         unsigned long n;
  48         fd_set __user *inp;
  49         fd_set __user *outp;
  50         fd_set __user *exp;
  51         struct timeval __user *tvp;
  52 };
  53
  54 long old_select(struct sel_arg_struct __user *arg)
  55 {
  56         struct sel_arg_struct a;
  57
  58         if (copy_from_user(&a, arg, sizeof(a)))
  59                 return -EFAULT;
  60         /* sys_select() does the appropriate kernel locking */
  61         return sys_select(a.n, a.inp, a.outp, a.exp, a.tvp);
  62 }
  63
  64 /*
  65  * The prototype on i386 is:
  66  *
  67  *     int clone(int flags, void * child_stack, int * parent_tidptr, struct user_desc * newtls, int * child_tidptr)
  68  *
  69  * and the "newtls" arg. on i386 is read by copy_thread directly from the
  70  * register saved on the stack.
  71  */
  72 long sys_clone(unsigned long clone_flags, unsigned long newsp,
  73                int __user *parent_tid, void *newtls, int __user *child_tid)
  74 {
  75         long ret;
  76
  77         if (!newsp)
  78                 newsp = UPT_SP(&current->thread.regs.regs);
  79
  80         current->thread.forking = 1;
  81         ret = do_fork(clone_flags, newsp, &current->thread.regs, 0, parent_tid,
  82                       child_tid);
  83         current->thread.forking = 0;
  84         return ret;
  85 }
  86
  87 /*
  88  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
  89  *
  90  * This is really horribly ugly.
  91  */
  92 long sys_ipc (uint call, int first, int second,
  93              int third, void __user *ptr, long fifth)
  94 {
  95         int version, ret;
  96
  97         version = call >> 16; /* hack for backward compatibility */
  98         call &= 0xffff;
  99
 100         switch (call) {
 101         case SEMOP:
 102                 return sys_semtimedop(first, (struct sembuf __user *) ptr,
 103                                       second, NULL);
 104         case SEMTIMEDOP:
 105                 return sys_semtimedop(first, (struct sembuf __user *) ptr,
 106                                       second,
 107                                       (const struct timespec __user *) fifth);
 108         case SEMGET:
 109                 return sys_semget (first, second, third);
 110         case SEMCTL: {
 111                 union semun fourth;
 112                 if (!ptr)
 113                         return -EINVAL;
 114                 if (get_user(fourth.__pad, (void __user * __user *) ptr))
 115                         return -EFAULT;
 116                 return sys_semctl (first, second, third, fourth);
 117         }
 118
 119         case MSGSND:
 120                 return sys_msgsnd (first, (struct msgbuf *) ptr,
 121                                    second, third);
 122         case MSGRCV:
 123                 switch (version) {
 124                 case 0: {
 125                         struct ipc_kludge tmp;
 126                         if (!ptr)
 127                                 return -EINVAL;
 128
 129                         if (copy_from_user(&tmp,
 130                                            (struct ipc_kludge *) ptr,
 131                                            sizeof (tmp)))
 132                                 return -EFAULT;
 133                         return sys_msgrcv (first, tmp.msgp, second,
 134                                            tmp.msgtyp, third);
 135                 }
 136                 default:
 137                         panic("msgrcv with version != 0");
 138                         return sys_msgrcv (first,
 139                                            (struct msgbuf *) ptr,
 140                                            second, fifth, third);
 141                 }
 142         case MSGGET:
 143                 return sys_msgget ((key_t) first, second);
 144         case MSGCTL:
 145                 return sys_msgctl (first, second, (struct msqid_ds *) ptr);
 146
 147         case SHMAT:
 148                 switch (version) {
 149                 default: {
 150                         ulong raddr;
 151                         ret = do_shmat (first, (char *) ptr, second, &raddr);
 152                         if (ret)
 153                                 return ret;
 154                         return put_user (raddr, (ulong *) third);
 155                 }
 156                 case 1: /* iBCS2 emulator entry point */
 157                         if (!segment_eq(get_fs(), get_ds()))
 158                                 return -EINVAL;
 159                         return do_shmat (first, (char *) ptr, second, (ulong *) third);
 160                 }
 161         case SHMDT:
 162                 return sys_shmdt ((char *)ptr);
 163         case SHMGET:
 164                 return sys_shmget (first, second, third);
 165         case SHMCTL:
 166                 return sys_shmctl (first, second,
 167                                    (struct shmid_ds *) ptr);
 168         default:
 169                 return -ENOSYS;
 170         }
 171 }
 172
 173 long sys_sigaction(int sig, const struct old_sigaction __user *act,
 174                          struct old_sigaction __user *oact)
 175 {
 176         struct k_sigaction new_ka, old_ka;
 177         int ret;
 178
 179         if (act) {
 180                 old_sigset_t mask;
 181                 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
 182                     __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
 183                     __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
 184                         return -EFAULT;
 185                 __get_user(new_ka.sa.sa_flags, &act->sa_flags);
 186                 __get_user(mask, &act->sa_mask);
 187                 siginitset(&new_ka.sa.sa_mask, mask);
 188         }
 189
 190         ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
 191
 192         if (!ret && oact) {
 193                 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
 194                     __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
 195                     __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
 196                         return -EFAULT;
 197                 __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
 198                 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
 199         }
 200
 201         return ret;
 202 }