arch/arm/kernel/sys_arm.c

   1 /*
   2  *  linux/arch/arm/kernel/sys_arm.c
   3  *
   4  *  Copyright (C) People who wrote linux/arch/i386/kernel/sys_i386.c
   5  *  Copyright (C) 1995, 1996 Russell King.
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  *  This file contains various random system calls that
  12  *  have a non-standard calling sequence on the Linux/arm
  13  *  platform.
  14  */
  15 #include <linux/module.h>
  16 #include <linux/errno.h>
  17 #include <linux/sched.h>
  18 #include <linux/slab.h>
  19 #include <linux/mm.h>
  20 #include <linux/sem.h>
  21 #include <linux/msg.h>
  22 #include <linux/shm.h>
  23 #include <linux/stat.h>
  24 #include <linux/syscalls.h>
  25 #include <linux/mman.h>
  26 #include <linux/fs.h>
  27 #include <linux/file.h>
  28 #include <linux/ipc.h>
  29 #include <linux/uaccess.h>
  30
  31 #if !defined(CONFIG_AEABI) || defined(CONFIG_OABI_COMPAT)
  32 /*
  33  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
  34  *
  35  * This is really horribly ugly.
  36  */
  37 asmlinkage int sys_ipc(uint call, int first, int second, int third,
  38                        void __user *ptr, long fifth)
  39 {
  40         int version, ret;
  41
  42         version = call >> 16; /* hack for backward compatibility */
  43         call &= 0xffff;
  44
  45         switch (call) {
  46         case SEMOP:
  47                 return sys_semtimedop (first, (struct sembuf __user *)ptr, second, NULL);
  48         case SEMTIMEDOP:
  49                 return sys_semtimedop(first, (struct sembuf __user *)ptr, second,
  50                                         (const struct timespec __user *)fifth);
  51
  52         case SEMGET:
  53                 return sys_semget (first, second, third);
  54         case SEMCTL: {
  55                 union semun fourth;
  56                 if (!ptr)
  57                         return -EINVAL;
  58                 if (get_user(fourth.__pad, (void __user * __user *) ptr))
  59                         return -EFAULT;
  60                 return sys_semctl (first, second, third, fourth);
  61         }
  62
  63         case MSGSND:
  64                 return sys_msgsnd(first, (struct msgbuf __user *) ptr,
  65                                   second, third);
  66         case MSGRCV:
  67                 switch (version) {
  68                 case 0: {
  69                         struct ipc_kludge tmp;
  70                         if (!ptr)
  71                                 return -EINVAL;
  72                         if (copy_from_user(&tmp,(struct ipc_kludge __user *)ptr,
  73                                            sizeof (tmp)))
  74                                 return -EFAULT;
  75                         return sys_msgrcv (first, tmp.msgp, second,
  76                                            tmp.msgtyp, third);
  77                 }
  78                 default:
  79                         return sys_msgrcv (first,
  80                                            (struct msgbuf __user *) ptr,
  81                                            second, fifth, third);
  82                 }
  83         case MSGGET:
  84                 return sys_msgget ((key_t) first, second);
  85         case MSGCTL:
  86                 return sys_msgctl(first, second, (struct msqid_ds __user *)ptr);
  87
  88         case SHMAT:
  89                 switch (version) {
  90                 default: {
  91                         ulong raddr;
  92                         ret = do_shmat(first, (char __user *)ptr, second, &raddr);
  93                         if (ret)
  94                                 return ret;
  95                         return put_user(raddr, (ulong __user *)third);
  96                 }
  97                 case 1: /* Of course, we don't support iBCS2! */
  98                         return -EINVAL;
  99                 }
 100         case SHMDT:
 101                 return sys_shmdt ((char __user *)ptr);
 102         case SHMGET:
 103                 return sys_shmget (first, second, third);
 104         case SHMCTL:
 105                 return sys_shmctl (first, second,
 106                                    (struct shmid_ds __user *) ptr);
 107         default:
 108                 return -ENOSYS;
 109         }
 110 }
 111 #endif
 112
 113 /* Fork a new task - this creates a new program thread.
 114  * This is called indirectly via a small wrapper
 115  */
 116 asmlinkage int sys_fork(struct pt_regs *regs)
 117 {
 118 #ifdef CONFIG_MMU
 119         return do_fork(SIGCHLD, regs->ARM_sp, regs, 0, NULL, NULL);
 120 #else
 121         /* can not support in nommu mode */
 122         return(-EINVAL);
 123 #endif
 124 }
 125
 126 /* Clone a task - this clones the calling program thread.
 127  * This is called indirectly via a small wrapper
 128  */
 129 asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
 130                          int __user *parent_tidptr, int tls_val,
 131                          int __user *child_tidptr, struct pt_regs *regs)
 132 {
 133         if (!newsp)
 134                 newsp = regs->ARM_sp;
 135
 136         return do_fork(clone_flags, newsp, regs, 0, parent_tidptr, child_tidptr);
 137 }
 138
 139 asmlinkage int sys_vfork(struct pt_regs *regs)
 140 {
 141         return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->ARM_sp, regs, 0, NULL, NULL);
 142 }
 143
 144 /* sys_execve() executes a new program.
 145  * This is called indirectly via a small wrapper
 146  */
 147 asmlinkage int sys_execve(char __user *filenamei, char __user * __user *argv,
 148                           char __user * __user *envp, struct pt_regs *regs)
 149 {
 150         int error;
 151         char * filename;
 152
 153         filename = getname(filenamei);
 154         error = PTR_ERR(filename);
 155         if (IS_ERR(filename))
 156                 goto out;
 157         error = do_execve(filename, argv, envp, regs);
 158         putname(filename);
 159 out:
 160         return error;
 161 }
 162
 163 int kernel_execve(const char *filename, char *const argv[], char *const envp[])
 164 {
 165         struct pt_regs regs;
 166         int ret;
 167
 168         memset(&regs, 0, sizeof(struct pt_regs));
 169         ret = do_execve((char *)filename, (char __user * __user *)argv,
 170                         (char __user * __user *)envp, &regs);
 171         if (ret < 0)
 172                 goto out;
 173
 174         /*
 175          * Save argc to the register structure for userspace.
 176          */
 177         regs.ARM_r0 = ret;
 178
 179         /*
 180          * We were successful.  We won't be returning to our caller, but
 181          * instead to user space by manipulating the kernel stack.
 182          */
 183         asm(    "add    r0, %0, %1\n\t"
 184                 "mov    r1, %2\n\t"
 185                 "mov    r2, %3\n\t"
 186                 "bl     memmove\n\t"    /* copy regs to top of stack */
 187                 "mov    r8, #0\n\t"     /* not a syscall */
 188                 "mov    r9, %0\n\t"     /* thread structure */
 189                 "mov    sp, r0\n\t"     /* reposition stack pointer */
 190                 "b      ret_to_user"
 191                 :
 192                 : "r" (current_thread_info()),
 193                   "Ir" (THREAD_START_SP - sizeof(regs)),
 194                   "r" (&regs),
 195                   "Ir" (sizeof(regs))
 196                 : "r0", "r1", "r2", "r3", "ip", "lr", "memory");
 197
 198  out:
 199         return ret;
 200 }
 201 EXPORT_SYMBOL(kernel_execve);
 202
 203 /*
 204  * Since loff_t is a 64 bit type we avoid a lot of ABI hassle
 205  * with a different argument ordering.
 206  */
 207 asmlinkage long sys_arm_fadvise64_64(int fd, int advice,
 208                                      loff_t offset, loff_t len)
 209 {
 210         return sys_fadvise64_64(fd, offset, len, advice);
 211 }