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