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 #include <linux/errno.h>
  11 #include <linux/sched.h>
  12 #include <linux/mm.h>
  13 #include <linux/smp.h>
  14 #include <linux/sem.h>
  15 #include <linux/msg.h>
  16 #include <linux/shm.h>
  17 #include <linux/stat.h>
  18 #include <linux/syscalls.h>
  19 #include <linux/mman.h>
  20 #include <linux/file.h>
  21 #include <linux/utsname.h>
  22 #include <linux/module.h>
  23 #include <linux/fs.h>
  24 #include <linux/ipc.h>
  25 #include <asm/cacheflush.h>
  26 #include <asm/uaccess.h>
  27 #include <asm/unistd.h>
  28
  29 unsigned long shm_align_mask = PAGE_SIZE - 1;   /* Sane caches */
  30 EXPORT_SYMBOL(shm_align_mask);
  31
  32 #ifdef CONFIG_MMU
  33 /*
  34  * To avoid cache aliases, we map the shared page with same color.
  35  */
  36 #define COLOUR_ALIGN(addr, pgoff)                               \
  37         ((((addr) + shm_align_mask) & ~shm_align_mask) +        \
  38          (((pgoff) << PAGE_SHIFT) & shm_align_mask))
  39
  40 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
  41         unsigned long len, unsigned long pgoff, unsigned long flags)
  42 {
  43         struct mm_struct *mm = current->mm;
  44         struct vm_area_struct *vma;
  45         unsigned long start_addr;
  46         int do_colour_align;
  47
  48         if (flags & MAP_FIXED) {
  49                 /* We do not accept a shared mapping if it would violate
  50                  * cache aliasing constraints.
  51                  */
  52                 if ((flags & MAP_SHARED) && (addr & shm_align_mask))
  53                         return -EINVAL;
  54                 return addr;
  55         }
  56
  57         if (unlikely(len > TASK_SIZE))
  58                 return -ENOMEM;
  59
  60         do_colour_align = 0;
  61         if (filp || (flags & MAP_SHARED))
  62                 do_colour_align = 1;
  63
  64         if (addr) {
  65                 if (do_colour_align)
  66                         addr = COLOUR_ALIGN(addr, pgoff);
  67                 else
  68                         addr = PAGE_ALIGN(addr);
  69
  70                 vma = find_vma(mm, addr);
  71                 if (TASK_SIZE - len >= addr &&
  72                     (!vma || addr + len <= vma->vm_start))
  73                         return addr;
  74         }
  75
  76         if (len > mm->cached_hole_size) {
  77                 start_addr = addr = mm->free_area_cache;
  78         } else {
  79                 mm->cached_hole_size = 0;
  80                 start_addr = addr = TASK_UNMAPPED_BASE;
  81         }
  82
  83 full_search:
  84         if (do_colour_align)
  85                 addr = COLOUR_ALIGN(addr, pgoff);
  86         else
  87                 addr = PAGE_ALIGN(mm->free_area_cache);
  88
  89         for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
  90                 /* At this point:  (!vma || addr < vma->vm_end). */
  91                 if (unlikely(TASK_SIZE - len < addr)) {
  92                         /*
  93                          * Start a new search - just in case we missed
  94                          * some holes.
  95                          */
  96                         if (start_addr != TASK_UNMAPPED_BASE) {
  97                                 start_addr = addr = TASK_UNMAPPED_BASE;
  98                                 mm->cached_hole_size = 0;
  99                                 goto full_search;
 100                         }
 101                         return -ENOMEM;
 102                 }
 103                 if (likely(!vma || addr + len <= vma->vm_start)) {
 104                         /*
 105                          * Remember the place where we stopped the search:
 106                          */
 107                         mm->free_area_cache = addr + len;
 108                         return addr;
 109                 }
 110                 if (addr + mm->cached_hole_size < vma->vm_start)
 111                         mm->cached_hole_size = vma->vm_start - addr;
 112
 113                 addr = vma->vm_end;
 114                 if (do_colour_align)
 115                         addr = COLOUR_ALIGN(addr, pgoff);
 116         }
 117 }
 118 #endif /* CONFIG_MMU */
 119
 120 static inline long
 121 do_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
 122          unsigned long flags, int fd, unsigned long pgoff)
 123 {
 124         int error = -EBADF;
 125         struct file *file = NULL;
 126
 127         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 128         if (!(flags & MAP_ANONYMOUS)) {
 129                 file = fget(fd);
 130                 if (!file)
 131                         goto out;
 132         }
 133
 134         down_write(&current->mm->mmap_sem);
 135         error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
 136         up_write(&current->mm->mmap_sem);
 137
 138         if (file)
 139                 fput(file);
 140 out:
 141         return error;
 142 }
 143
 144 asmlinkage int old_mmap(unsigned long addr, unsigned long len,
 145         unsigned long prot, unsigned long flags,
 146         int fd, unsigned long off)
 147 {
 148         if (off & ~PAGE_MASK)
 149                 return -EINVAL;
 150         return do_mmap2(addr, len, prot, flags, fd, off>>PAGE_SHIFT);
 151 }
 152
 153 asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
 154         unsigned long prot, unsigned long flags,
 155         unsigned long fd, unsigned long pgoff)
 156 {
 157         return do_mmap2(addr, len, prot, flags, fd, pgoff);
 158 }
 159
 160 /*
 161  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
 162  *
 163  * This is really horribly ugly.
 164  */
 165 asmlinkage int sys_ipc(uint call, int first, int second,
 166                        int third, void __user *ptr, long fifth)
 167 {
 168         int version, ret;
 169
 170         version = call >> 16; /* hack for backward compatibility */
 171         call &= 0xffff;
 172
 173         if (call <= SEMCTL)
 174                 switch (call) {
 175                 case SEMOP:
 176                         return sys_semtimedop(first,
 177                                               (struct sembuf __user *)ptr,
 178                                               second, NULL);
 179                 case SEMTIMEDOP:
 180                         return sys_semtimedop(first,
 181                                 (struct sembuf __user *)ptr, second,
 182                                 (const struct timespec __user *)fifth);
 183                 case SEMGET:
 184                         return sys_semget (first, second, third);
 185                 case SEMCTL: {
 186                         union semun fourth;
 187                         if (!ptr)
 188                                 return -EINVAL;
 189                         if (get_user(fourth.__pad, (void * __user *) ptr))
 190                                 return -EFAULT;
 191                         return sys_semctl (first, second, third, fourth);
 192                         }
 193                 default:
 194                         return -EINVAL;
 195                 }
 196
 197         if (call <= MSGCTL)
 198                 switch (call) {
 199                 case MSGSND:
 200                         return sys_msgsnd (first, (struct msgbuf __user *) ptr,
 201                                           second, third);
 202                 case MSGRCV:
 203                         switch (version) {
 204                         case 0:
 205                         {
 206                                 struct ipc_kludge tmp;
 207
 208                                 if (!ptr)
 209                                         return -EINVAL;
 210
 211                                 if (copy_from_user(&tmp,
 212                                         (struct ipc_kludge __user *) ptr,
 213                                                    sizeof (tmp)))
 214                                         return -EFAULT;
 215
 216                                 return sys_msgrcv (first, tmp.msgp, second,
 217                                                    tmp.msgtyp, third);
 218                         }
 219                         default:
 220                                 return sys_msgrcv (first,
 221                                                    (struct msgbuf __user *) ptr,
 222                                                    second, fifth, third);
 223                         }
 224                 case MSGGET:
 225                         return sys_msgget ((key_t) first, second);
 226                 case MSGCTL:
 227                         return sys_msgctl (first, second,
 228                                            (struct msqid_ds __user *) ptr);
 229                 default:
 230                         return -EINVAL;
 231                 }
 232         if (call <= SHMCTL)
 233                 switch (call) {
 234                 case SHMAT:
 235                         switch (version) {
 236                         default: {
 237                                 ulong raddr;
 238                                 ret = do_shmat (first, (char __user *) ptr,
 239                                                  second, &raddr);
 240                                 if (ret)
 241                                         return ret;
 242                                 return put_user (raddr, (ulong __user *) third);
 243                         }
 244                         case 1: /* iBCS2 emulator entry point */
 245                                 if (!segment_eq(get_fs(), get_ds()))
 246                                         return -EINVAL;
 247                                 return do_shmat (first, (char __user *) ptr,
 248                                                   second, (ulong *) third);
 249                         }
 250                 case SHMDT:
 251                         return sys_shmdt ((char __user *)ptr);
 252                 case SHMGET:
 253                         return sys_shmget (first, second, third);
 254                 case SHMCTL:
 255                         return sys_shmctl (first, second,
 256                                            (struct shmid_ds __user *) ptr);
 257                 default:
 258                         return -EINVAL;
 259                 }
 260
 261         return -EINVAL;
 262 }
 263
 264 asmlinkage int sys_uname(struct old_utsname * name)
 265 {
 266         int err;
 267         if (!name)
 268                 return -EFAULT;
 269         down_read(&uts_sem);
 270         err = copy_to_user(name, utsname(), sizeof (*name));
 271         up_read(&uts_sem);
 272         return err?-EFAULT:0;
 273 }