arch/sh/kernel/sys_sh.c

   1 /*
   2  * linux/arch/sh/kernel/sys_sh.c
   3  *
   4  * This file contains various random system calls that
   5  * have a non-standard calling sequence on the Linux/SuperH
   6  * platform.
   7  *
   8  * Taken from i386 version.
   9  */
  10
  11 #include <linux/errno.h>
  12 #include <linux/sched.h>
  13 #include <linux/mm.h>
  14 #include <linux/smp.h>
  15 #include <linux/sem.h>
  16 #include <linux/msg.h>
  17 #include <linux/shm.h>
  18 #include <linux/stat.h>
  19 #include <linux/syscalls.h>
  20 #include <linux/mman.h>
  21 #include <linux/file.h>
  22 #include <linux/utsname.h>
  23 #include <linux/module.h>
  24 #include <asm/cacheflush.h>
  25 #include <asm/uaccess.h>
  26 #include <asm/ipc.h>
  27 #include <asm/unistd.h>
  28
  29 /*
  30  * sys_pipe() is the normal C calling standard for creating
  31  * a pipe. It's not the way Unix traditionally does this, though.
  32  */
  33 asmlinkage int sys_pipe(unsigned long r4, unsigned long r5,
  34         unsigned long r6, unsigned long r7,
  35         struct pt_regs __regs)
  36 {
  37         struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
  38         int fd[2];
  39         int error;
  40
  41         error = do_pipe(fd);
  42         if (!error) {
  43                 regs->regs[1] = fd[1];
  44                 return fd[0];
  45         }
  46         return error;
  47 }
  48
  49 unsigned long shm_align_mask = PAGE_SIZE - 1;   /* Sane caches */
  50
  51 EXPORT_SYMBOL(shm_align_mask);
  52
  53 #ifdef CONFIG_MMU
  54 /*
  55  * To avoid cache aliases, we map the shared page with same color.
  56  */
  57 #define COLOUR_ALIGN(addr, pgoff)                               \
  58         ((((addr) + shm_align_mask) & ~shm_align_mask) +        \
  59          (((pgoff) << PAGE_SHIFT) & shm_align_mask))
  60
  61 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
  62         unsigned long len, unsigned long pgoff, unsigned long flags)
  63 {
  64         struct mm_struct *mm = current->mm;
  65         struct vm_area_struct *vma;
  66         unsigned long start_addr;
  67         int do_colour_align;
  68
  69         if (flags & MAP_FIXED) {
  70                 /* We do not accept a shared mapping if it would violate
  71                  * cache aliasing constraints.
  72                  */
  73                 if ((flags & MAP_SHARED) && (addr & shm_align_mask))
  74                         return -EINVAL;
  75                 return addr;
  76         }
  77
  78         if (unlikely(len > TASK_SIZE))
  79                 return -ENOMEM;
  80
  81         do_colour_align = 0;
  82         if (filp || (flags & MAP_SHARED))
  83                 do_colour_align = 1;
  84
  85         if (addr) {
  86                 if (do_colour_align)
  87                         addr = COLOUR_ALIGN(addr, pgoff);
  88                 else
  89                         addr = PAGE_ALIGN(addr);
  90
  91                 vma = find_vma(mm, addr);
  92                 if (TASK_SIZE - len >= addr &&
  93                     (!vma || addr + len <= vma->vm_start))
  94                         return addr;
  95         }
  96
  97         if (len > mm->cached_hole_size) {
  98                 start_addr = addr = mm->free_area_cache;
  99         } else {
 100                 mm->cached_hole_size = 0;
 101                 start_addr = addr = TASK_UNMAPPED_BASE;
 102         }
 103
 104 full_search:
 105         if (do_colour_align)
 106                 addr = COLOUR_ALIGN(addr, pgoff);
 107         else
 108                 addr = PAGE_ALIGN(mm->free_area_cache);
 109
 110         for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
 111                 /* At this point:  (!vma || addr < vma->vm_end). */
 112                 if (unlikely(TASK_SIZE - len < addr)) {
 113                         /*
 114                          * Start a new search - just in case we missed
 115                          * some holes.
 116                          */
 117                         if (start_addr != TASK_UNMAPPED_BASE) {
 118                                 start_addr = addr = TASK_UNMAPPED_BASE;
 119                                 mm->cached_hole_size = 0;
 120                                 goto full_search;
 121                         }
 122                         return -ENOMEM;
 123                 }
 124                 if (likely(!vma || addr + len <= vma->vm_start)) {
 125                         /*
 126                          * Remember the place where we stopped the search:
 127                          */
 128                         mm->free_area_cache = addr + len;
 129                         return addr;
 130                 }
 131                 if (addr + mm->cached_hole_size < vma->vm_start)
 132                         mm->cached_hole_size = vma->vm_start - addr;
 133
 134                 addr = vma->vm_end;
 135                 if (do_colour_align)
 136                         addr = COLOUR_ALIGN(addr, pgoff);
 137         }
 138 }
 139 #endif /* CONFIG_MMU */
 140
 141 static inline long
 142 do_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
 143          unsigned long flags, int fd, unsigned long pgoff)
 144 {
 145         int error = -EBADF;
 146         struct file *file = NULL;
 147
 148         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 149         if (!(flags & MAP_ANONYMOUS)) {
 150                 file = fget(fd);
 151                 if (!file)
 152                         goto out;
 153         }
 154
 155         down_write(&current->mm->mmap_sem);
 156         error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
 157         up_write(&current->mm->mmap_sem);
 158
 159         if (file)
 160                 fput(file);
 161 out:
 162         return error;
 163 }
 164
 165 asmlinkage int old_mmap(unsigned long addr, unsigned long len,
 166         unsigned long prot, unsigned long flags,
 167         int fd, unsigned long off)
 168 {
 169         if (off & ~PAGE_MASK)
 170                 return -EINVAL;
 171         return do_mmap2(addr, len, prot, flags, fd, off>>PAGE_SHIFT);
 172 }
 173
 174 asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
 175         unsigned long prot, unsigned long flags,
 176         unsigned long fd, unsigned long pgoff)
 177 {
 178         return do_mmap2(addr, len, prot, flags, fd, pgoff);
 179 }
 180
 181 /*
 182  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
 183  *
 184  * This is really horribly ugly.
 185  */
 186 asmlinkage int sys_ipc(uint call, int first, int second,
 187                        int third, void __user *ptr, long fifth)
 188 {
 189         int version, ret;
 190
 191         version = call >> 16; /* hack for backward compatibility */
 192         call &= 0xffff;
 193
 194         if (call <= SEMCTL)
 195                 switch (call) {
 196                 case SEMOP:
 197                         return sys_semtimedop(first, (struct sembuf __user *)ptr,
 198                                               second, NULL);
 199                 case SEMTIMEDOP:
 200                         return sys_semtimedop(first, (struct sembuf __user *)ptr,
 201                                               second,
 202                                               (const struct timespec __user *)fifth);
 203                 case SEMGET:
 204                         return sys_semget (first, second, third);
 205                 case SEMCTL: {
 206                         union semun fourth;
 207                         if (!ptr)
 208                                 return -EINVAL;
 209                         if (get_user(fourth.__pad, (void * __user *) ptr))
 210                                 return -EFAULT;
 211                         return sys_semctl (first, second, third, fourth);
 212                         }
 213                 default:
 214                         return -EINVAL;
 215                 }
 216
 217         if (call <= MSGCTL)
 218                 switch (call) {
 219                 case MSGSND:
 220                         return sys_msgsnd (first, (struct msgbuf __user *) ptr,
 221                                           second, third);
 222                 case MSGRCV:
 223                         switch (version) {
 224                         case 0: {
 225                                 struct ipc_kludge tmp;
 226                                 if (!ptr)
 227                                         return -EINVAL;
 228
 229                                 if (copy_from_user(&tmp,
 230                                                    (struct ipc_kludge __user *) ptr,
 231                                                    sizeof (tmp)))
 232                                         return -EFAULT;
 233                                 return sys_msgrcv (first, tmp.msgp, second,
 234                                                    tmp.msgtyp, third);
 235                                 }
 236                         default:
 237                                 return sys_msgrcv (first,
 238                                                    (struct msgbuf __user *) ptr,
 239                                                    second, fifth, third);
 240                         }
 241                 case MSGGET:
 242                         return sys_msgget ((key_t) first, second);
 243                 case MSGCTL:
 244                         return sys_msgctl (first, second,
 245                                            (struct msqid_ds __user *) ptr);
 246                 default:
 247                         return -EINVAL;
 248                 }
 249         if (call <= SHMCTL)
 250                 switch (call) {
 251                 case SHMAT:
 252                         switch (version) {
 253                         default: {
 254                                 ulong raddr;
 255                                 ret = do_shmat (first, (char __user *) ptr,
 256                                                  second, &raddr);
 257                                 if (ret)
 258                                         return ret;
 259                                 return put_user (raddr, (ulong __user *) third);
 260                         }
 261                         case 1: /* iBCS2 emulator entry point */
 262                                 if (!segment_eq(get_fs(), get_ds()))
 263                                         return -EINVAL;
 264                                 return do_shmat (first, (char __user *) ptr,
 265                                                   second, (ulong *) third);
 266                         }
 267                 case SHMDT:
 268                         return sys_shmdt ((char __user *)ptr);
 269                 case SHMGET:
 270                         return sys_shmget (first, second, third);
 271                 case SHMCTL:
 272                         return sys_shmctl (first, second,
 273                                            (struct shmid_ds __user *) ptr);
 274                 default:
 275                         return -EINVAL;
 276                 }
 277
 278         return -EINVAL;
 279 }
 280
 281 asmlinkage int sys_uname(struct old_utsname * name)
 282 {
 283         int err;
 284         if (!name)
 285                 return -EFAULT;
 286         down_read(&uts_sem);
 287         err = copy_to_user(name, utsname(), sizeof (*name));
 288         up_read(&uts_sem);
 289         return err?-EFAULT:0;
 290 }
 291
 292 asmlinkage ssize_t sys_pread_wrapper(unsigned int fd, char * buf,
 293                              size_t count, long dummy, loff_t pos)
 294 {
 295         return sys_pread64(fd, buf, count, pos);
 296 }
 297
 298 asmlinkage ssize_t sys_pwrite_wrapper(unsigned int fd, const char * buf,
 299                               size_t count, long dummy, loff_t pos)
 300 {
 301         return sys_pwrite64(fd, buf, count, pos);
 302 }
 303
 304 asmlinkage int sys_fadvise64_64_wrapper(int fd, u32 offset0, u32 offset1,
 305                                 u32 len0, u32 len1, int advice)
 306 {
 307 #ifdef  __LITTLE_ENDIAN__
 308         return sys_fadvise64_64(fd, (u64)offset1 << 32 | offset0,
 309                                 (u64)len1 << 32 | len0, advice);
 310 #else
 311         return sys_fadvise64_64(fd, (u64)offset0 << 32 | offset1,
 312                                 (u64)len0 << 32 | len1, advice);
 313 #endif
 314 }
 315
 316 #if defined(CONFIG_CPU_SH2) || defined(CONFIG_CPU_SH2A)
 317 #define SYSCALL_ARG3    "trapa #0x23"
 318 #else
 319 #define SYSCALL_ARG3    "trapa #0x13"
 320 #endif
 321
 322 /*
 323  * Do a system call from kernel instead of calling sys_execve so we
 324  * end up with proper pt_regs.
 325  */
 326 int kernel_execve(const char *filename, char *const argv[], char *const envp[])
 327 {
 328         register long __sc0 __asm__ ("r3") = __NR_execve;
 329         register long __sc4 __asm__ ("r4") = (long) filename;
 330         register long __sc5 __asm__ ("r5") = (long) argv;
 331         register long __sc6 __asm__ ("r6") = (long) envp;
 332         __asm__ __volatile__ (SYSCALL_ARG3 : "=z" (__sc0)
 333                         : "0" (__sc0), "r" (__sc4), "r" (__sc5), "r" (__sc6)
 334                         : "memory");
 335         return __sc0;
 336 }