arch/mips/kernel/syscall.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1995, 1996, 1997, 2000, 2001, 05 by Ralf Baechle
   7  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
   8  * Copyright (C) 2001 MIPS Technologies, Inc.
   9  */
  10 #include <linux/a.out.h>
  11 #include <linux/capability.h>
  12 #include <linux/errno.h>
  13 #include <linux/linkage.h>
  14 #include <linux/mm.h>
  15 #include <linux/fs.h>
  16 #include <linux/smp.h>
  17 #include <linux/mman.h>
  18 #include <linux/ptrace.h>
  19 #include <linux/sched.h>
  20 #include <linux/string.h>
  21 #include <linux/syscalls.h>
  22 #include <linux/file.h>
  23 #include <linux/slab.h>
  24 #include <linux/utsname.h>
  25 #include <linux/unistd.h>
  26 #include <linux/sem.h>
  27 #include <linux/msg.h>
  28 #include <linux/shm.h>
  29 #include <linux/compiler.h>
  30 #include <linux/module.h>
  31 #include <linux/ipc.h>
  32
  33 #include <asm/branch.h>
  34 #include <asm/cachectl.h>
  35 #include <asm/cacheflush.h>
  36 #include <asm/asm-offsets.h>
  37 #include <asm/signal.h>
  38 #include <asm/sim.h>
  39 #include <asm/shmparam.h>
  40 #include <asm/sysmips.h>
  41 #include <asm/uaccess.h>
  42
  43 asmlinkage int sys_pipe(nabi_no_regargs volatile struct pt_regs regs)
  44 {
  45         int fd[2];
  46         int error, res;
  47
  48         error = do_pipe(fd);
  49         if (error) {
  50                 res = error;
  51                 goto out;
  52         }
  53         regs.regs[3] = fd[1];
  54         res = fd[0];
  55 out:
  56         return res;
  57 }
  58
  59 unsigned long shm_align_mask = PAGE_SIZE - 1;   /* Sane caches */
  60
  61 EXPORT_SYMBOL(shm_align_mask);
  62
  63 #define COLOUR_ALIGN(addr,pgoff)                                \
  64         ((((addr) + shm_align_mask) & ~shm_align_mask) +        \
  65          (((pgoff) << PAGE_SHIFT) & shm_align_mask))
  66
  67 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
  68         unsigned long len, unsigned long pgoff, unsigned long flags)
  69 {
  70         struct vm_area_struct * vmm;
  71         int do_color_align;
  72         unsigned long task_size;
  73
  74         task_size = STACK_TOP;
  75
  76         if (len > task_size)
  77                 return -ENOMEM;
  78
  79         if (flags & MAP_FIXED) {
  80                 /* Even MAP_FIXED mappings must reside within task_size.  */
  81                 if (task_size - len < addr)
  82                         return -EINVAL;
  83
  84                 /*
  85                  * We do not accept a shared mapping if it would violate
  86                  * cache aliasing constraints.
  87                  */
  88                 if ((flags & MAP_SHARED) && (addr & shm_align_mask))
  89                         return -EINVAL;
  90                 return addr;
  91         }
  92
  93         do_color_align = 0;
  94         if (filp || (flags & MAP_SHARED))
  95                 do_color_align = 1;
  96         if (addr) {
  97                 if (do_color_align)
  98                         addr = COLOUR_ALIGN(addr, pgoff);
  99                 else
 100                         addr = PAGE_ALIGN(addr);
 101                 vmm = find_vma(current->mm, addr);
 102                 if (task_size - len >= addr &&
 103                     (!vmm || addr + len <= vmm->vm_start))
 104                         return addr;
 105         }
 106         addr = TASK_UNMAPPED_BASE;
 107         if (do_color_align)
 108                 addr = COLOUR_ALIGN(addr, pgoff);
 109         else
 110                 addr = PAGE_ALIGN(addr);
 111
 112         for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) {
 113                 /* At this point:  (!vmm || addr < vmm->vm_end). */
 114                 if (task_size - len < addr)
 115                         return -ENOMEM;
 116                 if (!vmm || addr + len <= vmm->vm_start)
 117                         return addr;
 118                 addr = vmm->vm_end;
 119                 if (do_color_align)
 120                         addr = COLOUR_ALIGN(addr, pgoff);
 121         }
 122 }
 123
 124 /* common code for old and new mmaps */
 125 static inline unsigned long
 126 do_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
 127         unsigned long flags, unsigned long fd, unsigned long pgoff)
 128 {
 129         unsigned long error = -EBADF;
 130         struct file * file = NULL;
 131
 132         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 133         if (!(flags & MAP_ANONYMOUS)) {
 134                 file = fget(fd);
 135                 if (!file)
 136                         goto out;
 137         }
 138
 139         down_write(&current->mm->mmap_sem);
 140         error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
 141         up_write(&current->mm->mmap_sem);
 142
 143         if (file)
 144                 fput(file);
 145 out:
 146         return error;
 147 }
 148
 149 asmlinkage unsigned long
 150 old_mmap(unsigned long addr, unsigned long len, int prot,
 151         int flags, int fd, off_t offset)
 152 {
 153         unsigned long result;
 154
 155         result = -EINVAL;
 156         if (offset & ~PAGE_MASK)
 157                 goto out;
 158
 159         result = do_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
 160
 161 out:
 162         return result;
 163 }
 164
 165 asmlinkage unsigned long
 166 sys_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
 167           unsigned long flags, unsigned long fd, unsigned long pgoff)
 168 {
 169         if (pgoff & (~PAGE_MASK >> 12))
 170                 return -EINVAL;
 171
 172         return do_mmap2(addr, len, prot, flags, fd, pgoff >> (PAGE_SHIFT-12));
 173 }
 174
 175 save_static_function(sys_fork);
 176 static int __used noinline
 177 _sys_fork(nabi_no_regargs struct pt_regs regs)
 178 {
 179         return do_fork(SIGCHLD, regs.regs[29], &regs, 0, NULL, NULL);
 180 }
 181
 182 save_static_function(sys_clone);
 183 static int __used noinline
 184 _sys_clone(nabi_no_regargs struct pt_regs regs)
 185 {
 186         unsigned long clone_flags;
 187         unsigned long newsp;
 188         int __user *parent_tidptr, *child_tidptr;
 189
 190         clone_flags = regs.regs[4];
 191         newsp = regs.regs[5];
 192         if (!newsp)
 193                 newsp = regs.regs[29];
 194         parent_tidptr = (int __user *) regs.regs[6];
 195 #ifdef CONFIG_32BIT
 196         /* We need to fetch the fifth argument off the stack.  */
 197         child_tidptr = NULL;
 198         if (clone_flags & (CLONE_CHILD_SETTID | CLONE_CHILD_CLEARTID)) {
 199                 int __user *__user *usp = (int __user *__user *) regs.regs[29];
 200                 if (regs.regs[2] == __NR_syscall) {
 201                         if (get_user (child_tidptr, &usp[5]))
 202                                 return -EFAULT;
 203                 }
 204                 else if (get_user (child_tidptr, &usp[4]))
 205                         return -EFAULT;
 206         }
 207 #else
 208         child_tidptr = (int __user *) regs.regs[8];
 209 #endif
 210         return do_fork(clone_flags, newsp, &regs, 0,
 211                        parent_tidptr, child_tidptr);
 212 }
 213
 214 /*
 215  * sys_execve() executes a new program.
 216  */
 217 asmlinkage int sys_execve(nabi_no_regargs struct pt_regs regs)
 218 {
 219         int error;
 220         char * filename;
 221
 222         filename = getname((char __user *) (long)regs.regs[4]);
 223         error = PTR_ERR(filename);
 224         if (IS_ERR(filename))
 225                 goto out;
 226         error = do_execve(filename, (char __user *__user *) (long)regs.regs[5],
 227                           (char __user *__user *) (long)regs.regs[6], &regs);
 228         putname(filename);
 229
 230 out:
 231         return error;
 232 }
 233
 234 /*
 235  * Compacrapability ...
 236  */
 237 asmlinkage int sys_uname(struct old_utsname __user * name)
 238 {
 239         if (name && !copy_to_user(name, utsname(), sizeof (*name)))
 240                 return 0;
 241         return -EFAULT;
 242 }
 243
 244 /*
 245  * Compacrapability ...
 246  */
 247 asmlinkage int sys_olduname(struct oldold_utsname __user * name)
 248 {
 249         int error;
 250
 251         if (!name)
 252                 return -EFAULT;
 253         if (!access_ok(VERIFY_WRITE, name, sizeof(struct oldold_utsname)))
 254                 return -EFAULT;
 255
 256         error = __copy_to_user(&name->sysname, &utsname()->sysname,
 257                                __OLD_UTS_LEN);
 258         error -= __put_user(0, name->sysname + __OLD_UTS_LEN);
 259         error -= __copy_to_user(&name->nodename, &utsname()->nodename,
 260                                 __OLD_UTS_LEN);
 261         error -= __put_user(0, name->nodename + __OLD_UTS_LEN);
 262         error -= __copy_to_user(&name->release, &utsname()->release,
 263                                 __OLD_UTS_LEN);
 264         error -= __put_user(0, name->release + __OLD_UTS_LEN);
 265         error -= __copy_to_user(&name->version, &utsname()->version,
 266                                 __OLD_UTS_LEN);
 267         error -= __put_user(0, name->version + __OLD_UTS_LEN);
 268         error -= __copy_to_user(&name->machine, &utsname()->machine,
 269                                 __OLD_UTS_LEN);
 270         error = __put_user(0, name->machine + __OLD_UTS_LEN);
 271         error = error ? -EFAULT : 0;
 272
 273         return error;
 274 }
 275
 276 asmlinkage int sys_set_thread_area(unsigned long addr)
 277 {
 278         struct thread_info *ti = task_thread_info(current);
 279
 280         ti->tp_value = addr;
 281         if (cpu_has_userlocal)
 282                 write_c0_userlocal(addr);
 283
 284         return 0;
 285 }
 286
 287 asmlinkage int _sys_sysmips(int cmd, long arg1, int arg2, int arg3)
 288 {
 289         switch (cmd) {
 290         case MIPS_ATOMIC_SET:
 291                 printk(KERN_CRIT "How did I get here?\n");
 292                 return -EINVAL;
 293
 294         case MIPS_FIXADE:
 295                 if (arg1 & ~3)
 296                         return -EINVAL;
 297
 298                 if (arg1 & 1)
 299                         set_thread_flag(TIF_FIXADE);
 300                 else
 301                         clear_thread_flag(TIF_FIXADE);
 302                 if (arg1 & 2)
 303                         set_thread_flag(TIF_LOGADE);
 304                 else
 305                         clear_thread_flag(TIF_FIXADE);
 306
 307                 return 0;
 308
 309         case FLUSH_CACHE:
 310                 __flush_cache_all();
 311                 return 0;
 312         }
 313
 314         return -EINVAL;
 315 }
 316
 317 /*
 318  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
 319  *
 320  * This is really horribly ugly.
 321  */
 322 asmlinkage int sys_ipc(unsigned int call, int first, int second,
 323                        unsigned long third, void __user *ptr, long fifth)
 324 {
 325         int version, ret;
 326
 327         version = call >> 16; /* hack for backward compatibility */
 328         call &= 0xffff;
 329
 330         switch (call) {
 331         case SEMOP:
 332                 return sys_semtimedop(first, (struct sembuf __user *)ptr,
 333                                       second, NULL);
 334         case SEMTIMEDOP:
 335                 return sys_semtimedop(first, (struct sembuf __user *)ptr,
 336                                       second,
 337                                       (const struct timespec __user *)fifth);
 338         case SEMGET:
 339                 return sys_semget(first, second, third);
 340         case SEMCTL: {
 341                 union semun fourth;
 342                 if (!ptr)
 343                         return -EINVAL;
 344                 if (get_user(fourth.__pad, (void __user *__user *) ptr))
 345                         return -EFAULT;
 346                 return sys_semctl(first, second, third, fourth);
 347         }
 348
 349         case MSGSND:
 350                 return sys_msgsnd(first, (struct msgbuf __user *) ptr,
 351                                   second, third);
 352         case MSGRCV:
 353                 switch (version) {
 354                 case 0: {
 355                         struct ipc_kludge tmp;
 356                         if (!ptr)
 357                                 return -EINVAL;
 358
 359                         if (copy_from_user(&tmp,
 360                                            (struct ipc_kludge __user *) ptr,
 361                                            sizeof(tmp)))
 362                                 return -EFAULT;
 363                         return sys_msgrcv(first, tmp.msgp, second,
 364                                           tmp.msgtyp, third);
 365                 }
 366                 default:
 367                         return sys_msgrcv(first,
 368                                           (struct msgbuf __user *) ptr,
 369                                           second, fifth, third);
 370                 }
 371         case MSGGET:
 372                 return sys_msgget((key_t) first, second);
 373         case MSGCTL:
 374                 return sys_msgctl(first, second,
 375                                   (struct msqid_ds __user *) ptr);
 376
 377         case SHMAT:
 378                 switch (version) {
 379                 default: {
 380                         unsigned long raddr;
 381                         ret = do_shmat(first, (char __user *) ptr, second,
 382                                        &raddr);
 383                         if (ret)
 384                                 return ret;
 385                         return put_user(raddr, (unsigned long __user *) third);
 386                 }
 387                 case 1: /* iBCS2 emulator entry point */
 388                         if (!segment_eq(get_fs(), get_ds()))
 389                                 return -EINVAL;
 390                         return do_shmat(first, (char __user *) ptr, second,
 391                                         (unsigned long *) third);
 392                 }
 393         case SHMDT:
 394                 return sys_shmdt((char __user *)ptr);
 395         case SHMGET:
 396                 return sys_shmget(first, second, third);
 397         case SHMCTL:
 398                 return sys_shmctl(first, second,
 399                                   (struct shmid_ds __user *) ptr);
 400         default:
 401                 return -ENOSYS;
 402         }
 403 }
 404
 405 /*
 406  * No implemented yet ...
 407  */
 408 asmlinkage int sys_cachectl(char *addr, int nbytes, int op)
 409 {
 410         return -ENOSYS;
 411 }
 412
 413 /*
 414  * If we ever come here the user sp is bad.  Zap the process right away.
 415  * Due to the bad stack signaling wouldn't work.
 416  */
 417 asmlinkage void bad_stack(void)
 418 {
 419         do_exit(SIGSEGV);
 420 }
 421
 422 /*
 423  * Do a system call from kernel instead of calling sys_execve so we
 424  * end up with proper pt_regs.
 425  */
 426 int kernel_execve(const char *filename, char *const argv[], char *const envp[])
 427 {
 428         register unsigned long __a0 asm("$4") = (unsigned long) filename;
 429         register unsigned long __a1 asm("$5") = (unsigned long) argv;
 430         register unsigned long __a2 asm("$6") = (unsigned long) envp;
 431         register unsigned long __a3 asm("$7");
 432         unsigned long __v0;
 433
 434         __asm__ volatile ("                                     \n"
 435         "       .set    noreorder                               \n"
 436         "       li      $2, %5          # __NR_execve           \n"
 437         "       syscall                                         \n"
 438         "       move    %0, $2                                  \n"
 439         "       .set    reorder                                 \n"
 440         : "=&r" (__v0), "=r" (__a3)
 441         : "r" (__a0), "r" (__a1), "r" (__a2), "i" (__NR_execve)
 442         : "$2", "$8", "$9", "$10", "$11", "$12", "$13", "$14", "$15", "$24",
 443           "memory");
 444
 445         if (__a3 == 0)
 446                 return __v0;
 447
 448         return -__v0;
 449 }