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/syscalls.h>
  27 #include <asm/uaccess.h>
  28 #include <asm/unistd.h>
  29
  30 unsigned long shm_align_mask = PAGE_SIZE - 1;   /* Sane caches */
  31 EXPORT_SYMBOL(shm_align_mask);
  32
  33 #ifdef CONFIG_MMU
  34 /*
  35  * To avoid cache aliases, we map the shared page with same color.
  36  */
  37 #define COLOUR_ALIGN(addr, pgoff)                               \
  38         ((((addr) + shm_align_mask) & ~shm_align_mask) +        \
  39          (((pgoff) << PAGE_SHIFT) & shm_align_mask))
  40
  41 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
  42         unsigned long len, unsigned long pgoff, unsigned long flags)
  43 {
  44         struct mm_struct *mm = current->mm;
  45         struct vm_area_struct *vma;
  46         unsigned long start_addr;
  47         int do_colour_align;
  48
  49         if (flags & MAP_FIXED) {
  50                 /* We do not accept a shared mapping if it would violate
  51                  * cache aliasing constraints.
  52                  */
  53                 if ((flags & MAP_SHARED) && (addr & shm_align_mask))
  54                         return -EINVAL;
  55                 return addr;
  56         }
  57
  58         if (unlikely(len > TASK_SIZE))
  59                 return -ENOMEM;
  60
  61         do_colour_align = 0;
  62         if (filp || (flags & MAP_SHARED))
  63                 do_colour_align = 1;
  64
  65         if (addr) {
  66                 if (do_colour_align)
  67                         addr = COLOUR_ALIGN(addr, pgoff);
  68                 else
  69                         addr = PAGE_ALIGN(addr);
  70
  71                 vma = find_vma(mm, addr);
  72                 if (TASK_SIZE - len >= addr &&
  73                     (!vma || addr + len <= vma->vm_start))
  74                         return addr;
  75         }
  76
  77         if (len > mm->cached_hole_size) {
  78                 start_addr = addr = mm->free_area_cache;
  79         } else {
  80                 mm->cached_hole_size = 0;
  81                 start_addr = addr = TASK_UNMAPPED_BASE;
  82         }
  83
  84 full_search:
  85         if (do_colour_align)
  86                 addr = COLOUR_ALIGN(addr, pgoff);
  87         else
  88                 addr = PAGE_ALIGN(mm->free_area_cache);
  89
  90         for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
  91                 /* At this point:  (!vma || addr < vma->vm_end). */
  92                 if (unlikely(TASK_SIZE - len < addr)) {
  93                         /*
  94                          * Start a new search - just in case we missed
  95                          * some holes.
  96                          */
  97                         if (start_addr != TASK_UNMAPPED_BASE) {
  98                                 start_addr = addr = TASK_UNMAPPED_BASE;
  99                                 mm->cached_hole_size = 0;
 100                                 goto full_search;
 101                         }
 102                         return -ENOMEM;
 103                 }
 104                 if (likely(!vma || addr + len <= vma->vm_start)) {
 105                         /*
 106                          * Remember the place where we stopped the search:
 107                          */
 108                         mm->free_area_cache = addr + len;
 109                         return addr;
 110                 }
 111                 if (addr + mm->cached_hole_size < vma->vm_start)
 112                         mm->cached_hole_size = vma->vm_start - addr;
 113
 114                 addr = vma->vm_end;
 115                 if (do_colour_align)
 116                         addr = COLOUR_ALIGN(addr, pgoff);
 117         }
 118 }
 119 #endif /* CONFIG_MMU */
 120
 121 static inline long
 122 do_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
 123          unsigned long flags, int fd, unsigned long pgoff)
 124 {
 125         int 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 int old_mmap(unsigned long addr, unsigned long len,
 146         unsigned long prot, unsigned long flags,
 147         int fd, unsigned long off)
 148 {
 149         if (off & ~PAGE_MASK)
 150                 return -EINVAL;
 151         return do_mmap2(addr, len, prot, flags, fd, off>>PAGE_SHIFT);
 152 }
 153
 154 asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
 155         unsigned long prot, unsigned long flags,
 156         unsigned long fd, unsigned long pgoff)
 157 {
 158         return do_mmap2(addr, len, prot, flags, fd, pgoff);
 159 }
 160
 161 /*
 162  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
 163  *
 164  * This is really horribly ugly.
 165  */
 166 asmlinkage int sys_ipc(uint call, int first, int second,
 167                        int third, void __user *ptr, long fifth)
 168 {
 169         int version, ret;
 170
 171         version = call >> 16; /* hack for backward compatibility */
 172         call &= 0xffff;
 173
 174         trace_mark(kernel_arch_ipc_call, "call %u first %d", call, first);
 175
 176         if (call <= SEMTIMEDOP)
 177                 switch (call) {
 178                 case SEMOP:
 179                         return sys_semtimedop(first,
 180                                               (struct sembuf __user *)ptr,
 181                                               second, NULL);
 182                 case SEMTIMEDOP:
 183                         return sys_semtimedop(first,
 184                                 (struct sembuf __user *)ptr, second,
 185                                 (const struct timespec __user *)fifth);
 186                 case SEMGET:
 187                         return sys_semget (first, second, third);
 188                 case SEMCTL: {
 189                         union semun fourth;
 190                         if (!ptr)
 191                                 return -EINVAL;
 192                         if (get_user(fourth.__pad, (void __user * __user *) ptr))
 193                                 return -EFAULT;
 194                         return sys_semctl (first, second, third, fourth);
 195                         }
 196                 default:
 197                         return -EINVAL;
 198                 }
 199
 200         if (call <= MSGCTL)
 201                 switch (call) {
 202                 case MSGSND:
 203                         return sys_msgsnd (first, (struct msgbuf __user *) ptr,
 204                                           second, third);
 205                 case MSGRCV:
 206                         switch (version) {
 207                         case 0:
 208                         {
 209                                 struct ipc_kludge tmp;
 210
 211                                 if (!ptr)
 212                                         return -EINVAL;
 213
 214                                 if (copy_from_user(&tmp,
 215                                         (struct ipc_kludge __user *) ptr,
 216                                                    sizeof (tmp)))
 217                                         return -EFAULT;
 218
 219                                 return sys_msgrcv (first, tmp.msgp, second,
 220                                                    tmp.msgtyp, third);
 221                         }
 222                         default:
 223                                 return sys_msgrcv (first,
 224                                                    (struct msgbuf __user *) ptr,
 225                                                    second, fifth, third);
 226                         }
 227                 case MSGGET:
 228                         return sys_msgget ((key_t) first, second);
 229                 case MSGCTL:
 230                         return sys_msgctl (first, second,
 231                                            (struct msqid_ds __user *) ptr);
 232                 default:
 233                         return -EINVAL;
 234                 }
 235         if (call <= SHMCTL)
 236                 switch (call) {
 237                 case SHMAT:
 238                         switch (version) {
 239                         default: {
 240                                 ulong raddr;
 241                                 ret = do_shmat (first, (char __user *) ptr,
 242                                                  second, &raddr);
 243                                 if (ret)
 244                                         return ret;
 245                                 return put_user (raddr, (ulong __user *) third);
 246                         }
 247                         case 1: /* iBCS2 emulator entry point */
 248                                 if (!segment_eq(get_fs(), get_ds()))
 249                                         return -EINVAL;
 250                                 return do_shmat (first, (char __user *) ptr,
 251                                                   second, (ulong *) third);
 252                         }
 253                 case SHMDT:
 254                         return sys_shmdt ((char __user *)ptr);
 255                 case SHMGET:
 256                         return sys_shmget (first, second, third);
 257                 case SHMCTL:
 258                         return sys_shmctl (first, second,
 259                                            (struct shmid_ds __user *) ptr);
 260                 default:
 261                         return -EINVAL;
 262                 }
 263
 264         return -EINVAL;
 265 }
 266
 267 asmlinkage int sys_uname(struct old_utsname __user *name)
 268 {
 269         int err;
 270         if (!name)
 271                 return -EFAULT;
 272         down_read(&uts_sem);
 273         err = copy_to_user(name, utsname(), sizeof(*name));
 274         up_read(&uts_sem);
 275         return err?-EFAULT:0;
 276 }