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/smp_lock.h>
  16 #include <linux/sem.h>
  17 #include <linux/msg.h>
  18 #include <linux/shm.h>
  19 #include <linux/stat.h>
  20 #include <linux/syscalls.h>
  21 #include <linux/mman.h>
  22 #include <linux/file.h>
  23 #include <linux/utsname.h>
  24 #include <linux/module.h>
  25 #include <asm/cacheflush.h>
  26 #include <asm/uaccess.h>
  27 #include <asm/ipc.h>
  28 #include <asm/unistd.h>
  29
  30 /*
  31  * sys_pipe() is the normal C calling standard for creating
  32  * a pipe. It's not the way Unix traditionally does this, though.
  33  */
  34 asmlinkage int sys_pipe(unsigned long r4, unsigned long r5,
  35         unsigned long r6, unsigned long r7,
  36         struct pt_regs __regs)
  37 {
  38         struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
  39         int fd[2];
  40         int error;
  41
  42         error = do_pipe(fd);
  43         if (!error) {
  44                 regs->regs[1] = fd[1];
  45                 return fd[0];
  46         }
  47         return error;
  48 }
  49
  50 unsigned long shm_align_mask = PAGE_SIZE - 1;   /* Sane caches */
  51
  52 EXPORT_SYMBOL(shm_align_mask);
  53
  54 #ifdef CONFIG_MMU
  55 /*
  56  * To avoid cache aliases, we map the shared page with same color.
  57  */
  58 #define COLOUR_ALIGN(addr, pgoff)                               \
  59         ((((addr) + shm_align_mask) & ~shm_align_mask) +        \
  60          (((pgoff) << PAGE_SHIFT) & shm_align_mask))
  61
  62 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
  63         unsigned long len, unsigned long pgoff, unsigned long flags)
  64 {
  65         struct mm_struct *mm = current->mm;
  66         struct vm_area_struct *vma;
  67         unsigned long start_addr;
  68         int do_colour_align;
  69
  70         if (flags & MAP_FIXED) {
  71                 /* We do not accept a shared mapping if it would violate
  72                  * cache aliasing constraints.
  73                  */
  74                 if ((flags & MAP_SHARED) && (addr & shm_align_mask))
  75                         return -EINVAL;
  76                 return addr;
  77         }
  78
  79         if (unlikely(len > TASK_SIZE))
  80                 return -ENOMEM;
  81
  82         do_colour_align = 0;
  83         if (filp || (flags & MAP_SHARED))
  84                 do_colour_align = 1;
  85
  86         if (addr) {
  87                 if (do_colour_align)
  88                         addr = COLOUR_ALIGN(addr, pgoff);
  89                 else
  90                         addr = PAGE_ALIGN(addr);
  91
  92                 vma = find_vma(mm, addr);
  93                 if (TASK_SIZE - len >= addr &&
  94                     (!vma || addr + len <= vma->vm_start))
  95                         return addr;
  96         }
  97
  98         if (len > mm->cached_hole_size) {
  99                 start_addr = addr = mm->free_area_cache;
 100         } else {
 101                 mm->cached_hole_size = 0;
 102                 start_addr = addr = TASK_UNMAPPED_BASE;
 103         }
 104
 105 full_search:
 106         if (do_colour_align)
 107                 addr = COLOUR_ALIGN(addr, pgoff);
 108         else
 109                 addr = PAGE_ALIGN(mm->free_area_cache);
 110
 111         for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
 112                 /* At this point:  (!vma || addr < vma->vm_end). */
 113                 if (unlikely(TASK_SIZE - len < addr)) {
 114                         /*
 115                          * Start a new search - just in case we missed
 116                          * some holes.
 117                          */
 118                         if (start_addr != TASK_UNMAPPED_BASE) {
 119                                 start_addr = addr = TASK_UNMAPPED_BASE;
 120                                 mm->cached_hole_size = 0;
 121                                 goto full_search;
 122                         }
 123                         return -ENOMEM;
 124                 }
 125                 if (likely(!vma || addr + len <= vma->vm_start)) {
 126                         /*
 127                          * Remember the place where we stopped the search:
 128                          */
 129                         mm->free_area_cache = addr + len;
 130                         return addr;
 131                 }
 132                 if (addr + mm->cached_hole_size < vma->vm_start)
 133                         mm->cached_hole_size = vma->vm_start - addr;
 134
 135                 addr = vma->vm_end;
 136                 if (do_colour_align)
 137                         addr = COLOUR_ALIGN(addr, pgoff);
 138         }
 139 }
 140 #endif /* CONFIG_MMU */
 141
 142 static inline long
 143 do_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
 144          unsigned long flags, int fd, unsigned long pgoff)
 145 {
 146         int error = -EBADF;
 147         struct file *file = NULL;
 148
 149         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 150         if (!(flags & MAP_ANONYMOUS)) {
 151                 file = fget(fd);
 152                 if (!file)
 153                         goto out;
 154         }
 155
 156         down_write(&current->mm->mmap_sem);
 157         error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
 158         up_write(&current->mm->mmap_sem);
 159
 160         if (file)
 161                 fput(file);
 162 out:
 163         return error;
 164 }
 165
 166 asmlinkage int old_mmap(unsigned long addr, unsigned long len,
 167         unsigned long prot, unsigned long flags,
 168         int fd, unsigned long off)
 169 {
 170         if (off & ~PAGE_MASK)
 171                 return -EINVAL;
 172         return do_mmap2(addr, len, prot, flags, fd, off>>PAGE_SHIFT);
 173 }
 174
 175 asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
 176         unsigned long prot, unsigned long flags,
 177         unsigned long fd, unsigned long pgoff)
 178 {
 179         return do_mmap2(addr, len, prot, flags, fd, pgoff);
 180 }
 181
 182 /*
 183  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
 184  *
 185  * This is really horribly ugly.
 186  */
 187 asmlinkage int sys_ipc(uint call, int first, int second,
 188                        int third, void __user *ptr, long fifth)
 189 {
 190         int version, ret;
 191
 192         version = call >> 16; /* hack for backward compatibility */
 193         call &= 0xffff;
 194
 195         if (call <= SEMCTL)
 196                 switch (call) {
 197                 case SEMOP:
 198                         return sys_semtimedop(first, (struct sembuf __user *)ptr,
 199                                               second, NULL);
 200                 case SEMTIMEDOP:
 201                         return sys_semtimedop(first, (struct sembuf __user *)ptr,
 202                                               second,
 203                                               (const struct timespec __user *)fifth);
 204                 case SEMGET:
 205                         return sys_semget (first, second, third);
 206                 case SEMCTL: {
 207                         union semun fourth;
 208                         if (!ptr)
 209                                 return -EINVAL;
 210                         if (get_user(fourth.__pad, (void * __user *) ptr))
 211                                 return -EFAULT;
 212                         return sys_semctl (first, second, third, fourth);
 213                         }
 214                 default:
 215                         return -EINVAL;
 216                 }
 217
 218         if (call <= MSGCTL)
 219                 switch (call) {
 220                 case MSGSND:
 221                         return sys_msgsnd (first, (struct msgbuf __user *) ptr,
 222                                           second, third);
 223                 case MSGRCV:
 224                         switch (version) {
 225                         case 0: {
 226                                 struct ipc_kludge tmp;
 227                                 if (!ptr)
 228                                         return -EINVAL;
 229
 230                                 if (copy_from_user(&tmp,
 231                                                    (struct ipc_kludge __user *) ptr,
 232                                                    sizeof (tmp)))
 233                                         return -EFAULT;
 234                                 return sys_msgrcv (first, tmp.msgp, second,
 235                                                    tmp.msgtyp, third);
 236                                 }
 237                         default:
 238                                 return sys_msgrcv (first,
 239                                                    (struct msgbuf __user *) ptr,
 240                                                    second, fifth, third);
 241                         }
 242                 case MSGGET:
 243                         return sys_msgget ((key_t) first, second);
 244                 case MSGCTL:
 245                         return sys_msgctl (first, second,
 246                                            (struct msqid_ds __user *) ptr);
 247                 default:
 248                         return -EINVAL;
 249                 }
 250         if (call <= SHMCTL)
 251                 switch (call) {
 252                 case SHMAT:
 253                         switch (version) {
 254                         default: {
 255                                 ulong raddr;
 256                                 ret = do_shmat (first, (char __user *) ptr,
 257                                                  second, &raddr);
 258                                 if (ret)
 259                                         return ret;
 260                                 return put_user (raddr, (ulong __user *) third);
 261                         }
 262                         case 1: /* iBCS2 emulator entry point */
 263                                 if (!segment_eq(get_fs(), get_ds()))
 264                                         return -EINVAL;
 265                                 return do_shmat (first, (char __user *) ptr,
 266                                                   second, (ulong *) third);
 267                         }
 268                 case SHMDT:
 269                         return sys_shmdt ((char __user *)ptr);
 270                 case SHMGET:
 271                         return sys_shmget (first, second, third);
 272                 case SHMCTL:
 273                         return sys_shmctl (first, second,
 274                                            (struct shmid_ds __user *) ptr);
 275                 default:
 276                         return -EINVAL;
 277                 }
 278
 279         return -EINVAL;
 280 }
 281
 282 asmlinkage int sys_uname(struct old_utsname * name)
 283 {
 284         int err;
 285         if (!name)
 286                 return -EFAULT;
 287         down_read(&uts_sem);
 288         err = copy_to_user(name, utsname(), sizeof (*name));
 289         up_read(&uts_sem);
 290         return err?-EFAULT:0;
 291 }
 292
 293 asmlinkage ssize_t sys_pread_wrapper(unsigned int fd, char * buf,
 294                              size_t count, long dummy, loff_t pos)
 295 {
 296         return sys_pread64(fd, buf, count, pos);
 297 }
 298
 299 asmlinkage ssize_t sys_pwrite_wrapper(unsigned int fd, const char * buf,
 300                               size_t count, long dummy, loff_t pos)
 301 {
 302         return sys_pwrite64(fd, buf, count, pos);
 303 }
 304
 305 asmlinkage int sys_fadvise64_64_wrapper(int fd, u32 offset0, u32 offset1,
 306                                 u32 len0, u32 len1, int advice)
 307 {
 308 #ifdef  __LITTLE_ENDIAN__
 309         return sys_fadvise64_64(fd, (u64)offset1 << 32 | offset0,
 310                                 (u64)len1 << 32 | len0, advice);
 311 #else
 312         return sys_fadvise64_64(fd, (u64)offset0 << 32 | offset1,
 313                                 (u64)len0 << 32 | len1, advice);
 314 #endif
 315 }
 316
 317 #if defined(CONFIG_CPU_SH2) || defined(CONFIG_CPU_SH2A)
 318 #define SYSCALL_ARG3    "trapa #0x23"
 319 #else
 320 #define SYSCALL_ARG3    "trapa #0x13"
 321 #endif
 322
 323 /*
 324  * Do a system call from kernel instead of calling sys_execve so we
 325  * end up with proper pt_regs.
 326  */
 327 int kernel_execve(const char *filename, char *const argv[], char *const envp[])
 328 {
 329         register long __sc0 __asm__ ("r3") = __NR_execve;
 330         register long __sc4 __asm__ ("r4") = (long) filename;
 331         register long __sc5 __asm__ ("r5") = (long) argv;
 332         register long __sc6 __asm__ ("r6") = (long) envp;
 333         __asm__ __volatile__ (SYSCALL_ARG3 : "=z" (__sc0)
 334                         : "0" (__sc0), "r" (__sc4), "r" (__sc5), "r" (__sc6)
 335                         : "memory");
 336         return __sc0;
 337 }