/*
 * linux/arch/m68k/kernel/sys_m68k.c
 *
 * This file contains various random system calls that
 * have a non-standard calling sequence on the Linux/m68k
 * platform.
 */

#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/sem.h>
#include <linux/msg.h>
#include <linux/shm.h>
#include <linux/stat.h>
#include <linux/syscalls.h>
#include <linux/mman.h>
#include <linux/file.h>
#include <linux/ipc.h>

#include <asm/setup.h>
#include <asm/uaccess.h>
#include <asm/cachectl.h>
#include <asm/traps.h>
#include <asm/page.h>
#include <asm/unistd.h>

/* common code for old and new mmaps */
static inline long do_mmap2(
        unsigned long addr, unsigned long len,
        unsigned long prot, unsigned long flags,
        unsigned long fd, unsigned long pgoff)
{
        int error = -EBADF;
        struct file * file = NULL;

        flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
        if (!(flags & MAP_ANONYMOUS)) {
                file = fget(fd);
                if (!file)
                        goto out;
        }

        down_write(&current->mm->mmap_sem);
        error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
        up_write(&current->mm->mmap_sem);

        if (file)
                fput(file);
out:
        return error;
}

asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
        unsigned long prot, unsigned long flags,
        unsigned long fd, unsigned long pgoff)
{
        return do_mmap2(addr, len, prot, flags, fd, pgoff);
}

/*
 * Perform the select(nd, in, out, ex, tv) and mmap() system
 * calls. Linux/m68k cloned Linux/i386, which didn't use to be able to
 * handle more than 4 system call parameters, so these system calls
 * used a memory block for parameter passing..
 */

struct mmap_arg_struct {
        unsigned long addr;
        unsigned long len;
        unsigned long prot;
        unsigned long flags;
        unsigned long fd;
        unsigned long offset;
};

asmlinkage int old_mmap(struct mmap_arg_struct __user *arg)
{
        struct mmap_arg_struct a;
        int error = -EFAULT;

        if (copy_from_user(&a, arg, sizeof(a)))
                goto out;

        error = -EINVAL;
        if (a.offset & ~PAGE_MASK)
                goto out;

        a.flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);

        error = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
out:
        return error;
}

#if 0
struct mmap_arg_struct64 {
        __u32 addr;
        __u32 len;
        __u32 prot;
        __u32 flags;
        __u64 offset; /* 64 bits */
        __u32 fd;
};

asmlinkage long sys_mmap64(struct mmap_arg_struct64 *arg)
{
        int error = -EFAULT;
        struct file * file = NULL;
        struct mmap_arg_struct64 a;
        unsigned long pgoff;

        if (copy_from_user(&a, arg, sizeof(a)))
                return -EFAULT;

        if ((long)a.offset & ~PAGE_MASK)
                return -EINVAL;

        pgoff = a.offset >> PAGE_SHIFT;
        if ((a.offset >> PAGE_SHIFT) != pgoff)
                return -EINVAL;

        if (!(a.flags & MAP_ANONYMOUS)) {
                error = -EBADF;
                file = fget(a.fd);
                if (!file)
                        goto out;
        }
        a.flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);

        down_write(&current->mm->mmap_sem);
        error = do_mmap_pgoff(file, a.addr, a.len, a.prot, a.flags, pgoff);
        up_write(&current->mm->mmap_sem);
        if (file)
                fput(file);
out:
        return error;
}
#endif

struct sel_arg_struct {
        unsigned long n;
        fd_set __user *inp, *outp, *exp;
        struct timeval __user *tvp;
};

asmlinkage int old_select(struct sel_arg_struct __user *arg)
{
        struct sel_arg_struct a;

        if (copy_from_user(&a, arg, sizeof(a)))
                return -EFAULT;
        /* sys_select() does the appropriate kernel locking */
        return sys_select(a.n, a.inp, a.outp, a.exp, a.tvp);
}

/*
 * sys_ipc() is the de-multiplexer for the SysV IPC calls..
 *
 * This is really horribly ugly.
 */
asmlinkage int sys_ipc (uint call, int first, int second,
                        int third, void __user *ptr, long fifth)
{
        int version, ret;

        version = call >> 16; /* hack for backward compatibility */
        call &= 0xffff;

        if (call <= SEMCTL)
                switch (call) {
                case SEMOP:
                        return sys_semop (first, ptr, second);
                case SEMGET:
                        return sys_semget (first, second, third);
                case SEMCTL: {
                        union semun fourth;
                        if (!ptr)
                                return -EINVAL;
                        if (get_user(fourth.__pad, (void __user *__user *) ptr))
                                return -EFAULT;
                        return sys_semctl (first, second, third, fourth);
                        }
                default:
                        return -ENOSYS;
                }
        if (call <= MSGCTL)
                switch (call) {
                case MSGSND:
                        return sys_msgsnd (first, ptr, second, third);
                case MSGRCV:
                        switch (version) {
                        case 0: {
                                struct ipc_kludge tmp;
                                if (!ptr)
                                        return -EINVAL;
                                if (copy_from_user (&tmp, ptr, sizeof (tmp)))
                                        return -EFAULT;
                                return sys_msgrcv (first, tmp.msgp, second,
                                                   tmp.msgtyp, third);
                                }
                        default:
                                return sys_msgrcv (first, ptr,
                                                   second, fifth, third);
                        }
                case MSGGET:
                        return sys_msgget ((key_t) first, second);
                case MSGCTL:
                        return sys_msgctl (first, second, ptr);
                default:
                        return -ENOSYS;
                }
        if (call <= SHMCTL)
                switch (call) {
                case SHMAT:
                        switch (version) {
                        default: {
                                ulong raddr;
                                ret = do_shmat (first, ptr, second, &raddr);
                                if (ret)
                                        return ret;
                                return put_user (raddr, (ulong __user *) third);
                        }
                        }
                case SHMDT:
                        return sys_shmdt (ptr);
                case SHMGET:
                        return sys_shmget (first, second, third);
                case SHMCTL:
                        return sys_shmctl (first, second, ptr);
                default:
                        return -ENOSYS;
                }

        return -EINVAL;
}

/* Convert virtual (user) address VADDR to physical address PADDR */
#define virt_to_phys_040(vaddr)                                         \
({                                                                      \
  unsigned long _mmusr, _paddr;                                         \
                                                                        \
  __asm__ __volatile__ (".chip 68040\n\t"                               \
                        "ptestr (%1)\n\t"                               \
                        "movec %%mmusr,%0\n\t"                          \
                        ".chip 68k"                                     \
                        : "=r" (_mmusr)                                 \
                        : "a" (vaddr));                                 \
  _paddr = (_mmusr & MMU_R_040) ? (_mmusr & PAGE_MASK) : 0;             \
  _paddr;                                                               \
})

static inline int
cache_flush_040 (unsigned long addr, int scope, int cache, unsigned long len)
{
  unsigned long paddr, i;

  switch (scope)
    {
    case FLUSH_SCOPE_ALL:
      switch (cache)
        {
        case FLUSH_CACHE_DATA:
          /* This nop is needed for some broken versions of the 68040.  */
          __asm__ __volatile__ ("nop\n\t"
                                ".chip 68040\n\t"
                                "cpusha %dc\n\t"
                                ".chip 68k");
          break;
        case FLUSH_CACHE_INSN:
          __asm__ __volatile__ ("nop\n\t"
                                ".chip 68040\n\t"
                                "cpusha %ic\n\t"
                                ".chip 68k");
          break;
        default:
        case FLUSH_CACHE_BOTH:
          __asm__ __volatile__ ("nop\n\t"
                                ".chip 68040\n\t"
                                "cpusha %bc\n\t"
                                ".chip 68k");
          break;
        }
      break;

    case FLUSH_SCOPE_LINE:
      /* Find the physical address of the first mapped page in the
         address range.  */
      if ((paddr = virt_to_phys_040(addr))) {
        paddr += addr & ~(PAGE_MASK | 15);
        len = (len + (addr & 15) + 15) >> 4;
      } else {
        unsigned long tmp = PAGE_SIZE - (addr & ~PAGE_MASK);

        if (len <= tmp)
          return 0;
        addr += tmp;
        len -= tmp;
        tmp = PAGE_SIZE;
        for (;;)
          {
            if ((paddr = virt_to_phys_040(addr)))
              break;
            if (len <= tmp)
              return 0;
            addr += tmp;
            len -= tmp;
          }
        len = (len + 15) >> 4;
      }
      i = (PAGE_SIZE - (paddr & ~PAGE_MASK)) >> 4;
      while (len--)
        {
          switch (cache)
            {
            case FLUSH_CACHE_DATA:
              __asm__ __volatile__ ("nop\n\t"
                                    ".chip 68040\n\t"
                                    "cpushl %%dc,(%0)\n\t"
                                    ".chip 68k"
                                    : : "a" (paddr));
              break;
            case FLUSH_CACHE_INSN:
              __asm__ __volatile__ ("nop\n\t"
                                    ".chip 68040\n\t"
                                    "cpushl %%ic,(%0)\n\t"
                                    ".chip 68k"
                                    : : "a" (paddr));
              break;
            default:
            case FLUSH_CACHE_BOTH:
              __asm__ __volatile__ ("nop\n\t"
                                    ".chip 68040\n\t"
                                    "cpushl %%bc,(%0)\n\t"
                                    ".chip 68k"
                                    : : "a" (paddr));
              break;
            }
          if (!--i && len)
            {
              /*
               * No need to page align here since it is done by
               * virt_to_phys_040().
               */
              addr += PAGE_SIZE;
              i = PAGE_SIZE / 16;
              /* Recompute physical address when crossing a page
                 boundary. */
              for (;;)
                {
                  if ((paddr = virt_to_phys_040(addr)))
                    break;
                  if (len <= i)
                    return 0;
                  len -= i;
                  addr += PAGE_SIZE;
                }
            }
          else
            paddr += 16;
        }
      break;

    default:
    case FLUSH_SCOPE_PAGE:
      len += (addr & ~PAGE_MASK) + (PAGE_SIZE - 1);
      for (len >>= PAGE_SHIFT; len--; addr += PAGE_SIZE)
        {
          if (!(paddr = virt_to_phys_040(addr)))
            continue;
          switch (cache)
            {
            case FLUSH_CACHE_DATA:
              __asm__ __volatile__ ("nop\n\t"
                                    ".chip 68040\n\t"
                                    "cpushp %%dc,(%0)\n\t"
                                    ".chip 68k"
                                    : : "a" (paddr));
              break;
            case FLUSH_CACHE_INSN:
              __asm__ __volatile__ ("nop\n\t"
                                    ".chip 68040\n\t"
                                    "cpushp %%ic,(%0)\n\t"
                                    ".chip 68k"
                                    : : "a" (paddr));
              break;
            default:
            case FLUSH_CACHE_BOTH:
              __asm__ __volatile__ ("nop\n\t"
                                    ".chip 68040\n\t"
                                    "cpushp %%bc,(%0)\n\t"
                                    ".chip 68k"
                                    : : "a" (paddr));
              break;
            }
        }
      break;
    }
  return 0;
}

#define virt_to_phys_060(vaddr)                         \
({                                                      \
  unsigned long paddr;                                  \
  __asm__ __volatile__ (".chip 68060\n\t"               \
                        "plpar (%0)\n\t"                \
                        ".chip 68k"                     \
                        : "=a" (paddr)                  \
                        : "0" (vaddr));                 \
  (paddr); /* XXX */                                    \
})

static inline int
cache_flush_060 (unsigned long addr, int scope, int cache, unsigned long len)
{
  unsigned long paddr, i;

  /*
   * 68060 manual says:
   *  cpush %dc : flush DC, remains valid (with our %cacr setup)
   *  cpush %ic : invalidate IC
   *  cpush %bc : flush DC + invalidate IC
   */
  switch (scope)
    {
    case FLUSH_SCOPE_ALL:
      switch (cache)
        {
        case FLUSH_CACHE_DATA:
          __asm__ __volatile__ (".chip 68060\n\t"
                                "cpusha %dc\n\t"
                                ".chip 68k");
          break;
        case FLUSH_CACHE_INSN:
          __asm__ __volatile__ (".chip 68060\n\t"
                                "cpusha %ic\n\t"
                                ".chip 68k");
          break;
        default:
        case FLUSH_CACHE_BOTH:
          __asm__ __volatile__ (".chip 68060\n\t"
                                "cpusha %bc\n\t"
                                ".chip 68k");
          break;
        }
      break;

    case FLUSH_SCOPE_LINE:
      /* Find the physical address of the first mapped page in the
         address range.  */
      len += addr & 15;
      addr &= -16;
      if (!(paddr = virt_to_phys_060(addr))) {
        unsigned long tmp = PAGE_SIZE - (addr & ~PAGE_MASK);

        if (len <= tmp)
          return 0;
        addr += tmp;
        len -= tmp;
        tmp = PAGE_SIZE;
        for (;;)
          {
            if ((paddr = virt_to_phys_060(addr)))
              break;
            if (len <= tmp)
              return 0;
            addr += tmp;
            len -= tmp;
          }
      }
      len = (len + 15) >> 4;
      i = (PAGE_SIZE - (paddr & ~PAGE_MASK)) >> 4;
      while (len--)
        {
          switch (cache)
            {
            case FLUSH_CACHE_DATA:
              __asm__ __volatile__ (".chip 68060\n\t"
                                    "cpushl %%dc,(%0)\n\t"
                                    ".chip 68k"
                                    : : "a" (paddr));
              break;
            case FLUSH_CACHE_INSN:
              __asm__ __volatile__ (".chip 68060\n\t"
                                    "cpushl %%ic,(%0)\n\t"
                                    ".chip 68k"
                                    : : "a" (paddr));
              break;
            default:
            case FLUSH_CACHE_BOTH:
              __asm__ __volatile__ (".chip 68060\n\t"
                                    "cpushl %%bc,(%0)\n\t"
                                    ".chip 68k"
                                    : : "a" (paddr));
              break;
            }
          if (!--i && len)
            {

              /*
               * We just want to jump to the first cache line
               * in the next page.
               */
              addr += PAGE_SIZE;
              addr &= PAGE_MASK;

              i = PAGE_SIZE / 16;
              /* Recompute physical address when crossing a page
                 boundary. */
              for (;;)
                {
                  if ((paddr = virt_to_phys_060(addr)))
                    break;
                  if (len <= i)
                    return 0;
                  len -= i;
                  addr += PAGE_SIZE;
                }
            }
          else
            paddr += 16;
        }
      break;

    default:
    case FLUSH_SCOPE_PAGE:
      len += (addr & ~PAGE_MASK) + (PAGE_SIZE - 1);
      addr &= PAGE_MASK;        /* Workaround for bug in some
                                   revisions of the 68060 */
      for (len >>= PAGE_SHIFT; len--; addr += PAGE_SIZE)
        {
          if (!(paddr = virt_to_phys_060(addr)))
            continue;
          switch (cache)
            {
            case FLUSH_CACHE_DATA:
              __asm__ __volatile__ (".chip 68060\n\t"
                                    "cpushp %%dc,(%0)\n\t"
                                    ".chip 68k"
                                    : : "a" (paddr));
              break;
            case FLUSH_CACHE_INSN:
              __asm__ __volatile__ (".chip 68060\n\t"
                                    "cpushp %%ic,(%0)\n\t"
                                    ".chip 68k"
                                    : : "a" (paddr));
              break;
            default:
            case FLUSH_CACHE_BOTH:
              __asm__ __volatile__ (".chip 68060\n\t"
                                    "cpushp %%bc,(%0)\n\t"
                                    ".chip 68k"
                                    : : "a" (paddr));
              break;
            }
        }
      break;
    }
  return 0;
}

/* sys_cacheflush -- flush (part of) the processor cache.  */
asmlinkage int
sys_cacheflush (unsigned long addr, int scope, int cache, unsigned long len)
{
        struct vm_area_struct *vma;
        int ret = -EINVAL;

        lock_kernel();
        if (scope < FLUSH_SCOPE_LINE || scope > FLUSH_SCOPE_ALL ||
            cache & ~FLUSH_CACHE_BOTH)
                goto out;

        if (scope == FLUSH_SCOPE_ALL) {
                /* Only the superuser may explicitly flush the whole cache. */
                ret = -EPERM;
                if (!capable(CAP_SYS_ADMIN))
                        goto out;
        } else {
                /*
                 * Verify that the specified address region actually belongs
                 * to this process.
                 */
                vma = find_vma (current->mm, addr);
                ret = -EINVAL;
                /* Check for overflow.  */
                if (addr + len < addr)
                        goto out;
                if (vma == NULL || addr < vma->vm_start || addr + len > vma->vm_end)
                        goto out;
        }

        if (CPU_IS_020_OR_030) {
                if (scope == FLUSH_SCOPE_LINE && len < 256) {
                        unsigned long cacr;
                        __asm__ ("movec %%cacr, %0" : "=r" (cacr));
                        if (cache & FLUSH_CACHE_INSN)
                                cacr |= 4;
                        if (cache & FLUSH_CACHE_DATA)
                                cacr |= 0x400;
                        len >>= 2;
                        while (len--) {
                                __asm__ __volatile__ ("movec %1, %%caar\n\t"
                                                      "movec %0, %%cacr"
                                                      : /* no outputs */
                                                      : "r" (cacr), "r" (addr));
                                addr += 4;
                        }
                } else {
                        /* Flush the whole cache, even if page granularity requested. */
                        unsigned long cacr;
                        __asm__ ("movec %%cacr, %0" : "=r" (cacr));
                        if (cache & FLUSH_CACHE_INSN)
                                cacr |= 8;
                        if (cache & FLUSH_CACHE_DATA)
                                cacr |= 0x800;
                        __asm__ __volatile__ ("movec %0, %%cacr" : : "r" (cacr));
                }
                ret = 0;
                goto out;
        } else {
            /*
             * 040 or 060: don't blindly trust 'scope', someone could
             * try to flush a few megs of memory.
             */

            if (len>=3*PAGE_SIZE && scope<FLUSH_SCOPE_PAGE)
                scope=FLUSH_SCOPE_PAGE;
            if (len>=10*PAGE_SIZE && scope<FLUSH_SCOPE_ALL)
                scope=FLUSH_SCOPE_ALL;
            if (CPU_IS_040) {
                ret = cache_flush_040 (addr, scope, cache, len);
            } else if (CPU_IS_060) {
                ret = cache_flush_060 (addr, scope, cache, len);
            }
        }
out:
        unlock_kernel();
        return ret;
}

asmlinkage int sys_getpagesize(void)
{
        return PAGE_SIZE;
}

/*
 * Do a system call from kernel instead of calling sys_execve so we
 * end up with proper pt_regs.
 */
int kernel_execve(const char *filename, char *const argv[], char *const envp[])
{
        register long __res asm ("%d0") = __NR_execve;
        register long __a asm ("%d1") = (long)(filename);
        register long __b asm ("%d2") = (long)(argv);
        register long __c asm ("%d3") = (long)(envp);
        asm volatile ("trap  #0" : "+d" (__res)
                        : "d" (__a), "d" (__b), "d" (__c));
        return __res;
}