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/utsname.h>
  29 #include <linux/ipc.h>
  30
  31 #include <asm/uaccess.h>
  32
  33 extern unsigned long do_mremap(unsigned long addr, unsigned long old_len,
  34                                unsigned long new_len, unsigned long flags,
  35                                unsigned long new_addr);
  36
  37 /* common code for old and new mmaps */
  38 inline long do_mmap2(
  39         unsigned long addr, unsigned long len,
  40         unsigned long prot, unsigned long flags,
  41         unsigned long fd, unsigned long pgoff)
  42 {
  43         int error = -EINVAL;
  44         struct file * file = NULL;
  45
  46         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
  47
  48         if (flags & MAP_FIXED && addr < FIRST_USER_ADDRESS)
  49                 goto out;
  50
  51         error = -EBADF;
  52         if (!(flags & MAP_ANONYMOUS)) {
  53                 file = fget(fd);
  54                 if (!file)
  55                         goto out;
  56         }
  57
  58         down_write(&current->mm->mmap_sem);
  59         error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
  60         up_write(&current->mm->mmap_sem);
  61
  62         if (file)
  63                 fput(file);
  64 out:
  65         return error;
  66 }
  67
  68 struct mmap_arg_struct {
  69         unsigned long addr;
  70         unsigned long len;
  71         unsigned long prot;
  72         unsigned long flags;
  73         unsigned long fd;
  74         unsigned long offset;
  75 };
  76
  77 asmlinkage int old_mmap(struct mmap_arg_struct __user *arg)
  78 {
  79         int error = -EFAULT;
  80         struct mmap_arg_struct a;
  81
  82         if (copy_from_user(&a, arg, sizeof(a)))
  83                 goto out;
  84
  85         error = -EINVAL;
  86         if (a.offset & ~PAGE_MASK)
  87                 goto out;
  88
  89         error = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
  90 out:
  91         return error;
  92 }
  93
  94 asmlinkage unsigned long
  95 sys_arm_mremap(unsigned long addr, unsigned long old_len,
  96                unsigned long new_len, unsigned long flags,
  97                unsigned long new_addr)
  98 {
  99         unsigned long ret = -EINVAL;
 100
 101         if (flags & MREMAP_FIXED && new_addr < FIRST_USER_ADDRESS)
 102                 goto out;
 103
 104         down_write(&current->mm->mmap_sem);
 105         ret = do_mremap(addr, old_len, new_len, flags, new_addr);
 106         up_write(&current->mm->mmap_sem);
 107
 108 out:
 109         return ret;
 110 }
 111
 112 /*
 113  * Perform the select(nd, in, out, ex, tv) and mmap() system
 114  * calls.
 115  */
 116
 117 struct sel_arg_struct {
 118         unsigned long n;
 119         fd_set __user *inp, *outp, *exp;
 120         struct timeval __user *tvp;
 121 };
 122
 123 asmlinkage int old_select(struct sel_arg_struct __user *arg)
 124 {
 125         struct sel_arg_struct a;
 126
 127         if (copy_from_user(&a, arg, sizeof(a)))
 128                 return -EFAULT;
 129         /* sys_select() does the appropriate kernel locking */
 130         return sys_select(a.n, a.inp, a.outp, a.exp, a.tvp);
 131 }
 132
 133 #if !defined(CONFIG_AEABI) || defined(CONFIG_OABI_COMPAT)
 134 /*
 135  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
 136  *
 137  * This is really horribly ugly.
 138  */
 139 asmlinkage int sys_ipc(uint call, int first, int second, int third,
 140                        void __user *ptr, long fifth)
 141 {
 142         int version, ret;
 143
 144         version = call >> 16; /* hack for backward compatibility */
 145         call &= 0xffff;
 146
 147         switch (call) {
 148         case SEMOP:
 149                 return sys_semtimedop (first, (struct sembuf __user *)ptr, second, NULL);
 150         case SEMTIMEDOP:
 151                 return sys_semtimedop(first, (struct sembuf __user *)ptr, second,
 152                                         (const struct timespec __user *)fifth);
 153
 154         case SEMGET:
 155                 return sys_semget (first, second, third);
 156         case SEMCTL: {
 157                 union semun fourth;
 158                 if (!ptr)
 159                         return -EINVAL;
 160                 if (get_user(fourth.__pad, (void __user * __user *) ptr))
 161                         return -EFAULT;
 162                 return sys_semctl (first, second, third, fourth);
 163         }
 164
 165         case MSGSND:
 166                 return sys_msgsnd(first, (struct msgbuf __user *) ptr,
 167                                   second, third);
 168         case MSGRCV:
 169                 switch (version) {
 170                 case 0: {
 171                         struct ipc_kludge tmp;
 172                         if (!ptr)
 173                                 return -EINVAL;
 174                         if (copy_from_user(&tmp,(struct ipc_kludge __user *)ptr,
 175                                            sizeof (tmp)))
 176                                 return -EFAULT;
 177                         return sys_msgrcv (first, tmp.msgp, second,
 178                                            tmp.msgtyp, third);
 179                 }
 180                 default:
 181                         return sys_msgrcv (first,
 182                                            (struct msgbuf __user *) ptr,
 183                                            second, fifth, third);
 184                 }
 185         case MSGGET:
 186                 return sys_msgget ((key_t) first, second);
 187         case MSGCTL:
 188                 return sys_msgctl(first, second, (struct msqid_ds __user *)ptr);
 189
 190         case SHMAT:
 191                 switch (version) {
 192                 default: {
 193                         ulong raddr;
 194                         ret = do_shmat(first, (char __user *)ptr, second, &raddr);
 195                         if (ret)
 196                                 return ret;
 197                         return put_user(raddr, (ulong __user *)third);
 198                 }
 199                 case 1: /* Of course, we don't support iBCS2! */
 200                         return -EINVAL;
 201                 }
 202         case SHMDT:
 203                 return sys_shmdt ((char __user *)ptr);
 204         case SHMGET:
 205                 return sys_shmget (first, second, third);
 206         case SHMCTL:
 207                 return sys_shmctl (first, second,
 208                                    (struct shmid_ds __user *) ptr);
 209         default:
 210                 return -ENOSYS;
 211         }
 212 }
 213 #endif
 214
 215 /* Fork a new task - this creates a new program thread.
 216  * This is called indirectly via a small wrapper
 217  */
 218 asmlinkage int sys_fork(struct pt_regs *regs)
 219 {
 220 #ifdef CONFIG_MMU
 221         return do_fork(SIGCHLD, regs->ARM_sp, regs, 0, NULL, NULL);
 222 #else
 223         /* can not support in nommu mode */
 224         return(-EINVAL);
 225 #endif
 226 }
 227
 228 /* Clone a task - this clones the calling program thread.
 229  * This is called indirectly via a small wrapper
 230  */
 231 asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
 232                          int __user *parent_tidptr, int tls_val,
 233                          int __user *child_tidptr, struct pt_regs *regs)
 234 {
 235         if (!newsp)
 236                 newsp = regs->ARM_sp;
 237
 238         return do_fork(clone_flags, newsp, regs, 0, parent_tidptr, child_tidptr);
 239 }
 240
 241 asmlinkage int sys_vfork(struct pt_regs *regs)
 242 {
 243         return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->ARM_sp, regs, 0, NULL, NULL);
 244 }
 245
 246 /* sys_execve() executes a new program.
 247  * This is called indirectly via a small wrapper
 248  */
 249 asmlinkage int sys_execve(char __user *filenamei, char __user * __user *argv,
 250                           char __user * __user *envp, struct pt_regs *regs)
 251 {
 252         int error;
 253         char * filename;
 254
 255         filename = getname(filenamei);
 256         error = PTR_ERR(filename);
 257         if (IS_ERR(filename))
 258                 goto out;
 259         error = do_execve(filename, argv, envp, regs);
 260         putname(filename);
 261 out:
 262         return error;
 263 }
 264
 265 int kernel_execve(const char *filename, char *const argv[], char *const envp[])
 266 {
 267         struct pt_regs regs;
 268         int ret;
 269
 270         memset(&regs, 0, sizeof(struct pt_regs));
 271         ret = do_execve((char *)filename, (char __user * __user *)argv,
 272                         (char __user * __user *)envp, &regs);
 273         if (ret < 0)
 274                 goto out;
 275
 276         /*
 277          * Save argc to the register structure for userspace.
 278          */
 279         regs.ARM_r0 = ret;
 280
 281         /*
 282          * We were successful.  We won't be returning to our caller, but
 283          * instead to user space by manipulating the kernel stack.
 284          */
 285         asm(    "add    r0, %0, %1\n\t"
 286                 "mov    r1, %2\n\t"
 287                 "mov    r2, %3\n\t"
 288                 "bl     memmove\n\t"    /* copy regs to top of stack */
 289                 "mov    r8, #0\n\t"     /* not a syscall */
 290                 "mov    r9, %0\n\t"     /* thread structure */
 291                 "mov    sp, r0\n\t"     /* reposition stack pointer */
 292                 "b      ret_to_user"
 293                 :
 294                 : "r" (current_thread_info()),
 295                   "Ir" (THREAD_START_SP - sizeof(regs)),
 296                   "r" (&regs),
 297                   "Ir" (sizeof(regs))
 298                 : "r0", "r1", "r2", "r3", "ip", "lr", "memory");
 299
 300  out:
 301         return ret;
 302 }
 303 EXPORT_SYMBOL(kernel_execve);
 304
 305 /*
 306  * Since loff_t is a 64 bit type we avoid a lot of ABI hassle
 307  * with a different argument ordering.
 308  */
 309 asmlinkage long sys_arm_fadvise64_64(int fd, int advice,
 310                                      loff_t offset, loff_t len)
 311 {
 312         return sys_fadvise64_64(fd, offset, len, advice);
 313 }