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