/*
 * This file contains various system calls that have different calling
 * conventions on different platforms.
 *
 * Copyright (C) 1999-2000, 2002-2003, 2005 Hewlett-Packard Co
 *      David Mosberger-Tang <davidm@hpl.hp.com>
 */
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/sched.h>
#include <linux/shm.h>
#include <linux/file.h>         /* doh, must come after sched.h... */
#include <linux/smp.h>
#include <linux/syscalls.h>
#include <linux/highuid.h>
#include <linux/hugetlb.h>

#include <asm/shmparam.h>
#include <asm/uaccess.h>

unsigned long
arch_get_unmapped_area (struct file *filp, unsigned long addr, unsigned long len,
                        unsigned long pgoff, unsigned long flags)
{
        long map_shared = (flags & MAP_SHARED);
        unsigned long start_addr, align_mask = PAGE_SIZE - 1;
        struct mm_struct *mm = current->mm;
        struct vm_area_struct *vma;

        if (len > RGN_MAP_LIMIT)
                return -ENOMEM;

        /* handle fixed mapping: prevent overlap with huge pages */
        if (flags & MAP_FIXED) {
                if (is_hugepage_only_range(mm, addr, len))
                        return -EINVAL;
                return addr;
        }

#ifdef CONFIG_HUGETLB_PAGE
        if (REGION_NUMBER(addr) == RGN_HPAGE)
                addr = 0;
#endif
        if (!addr)
                addr = mm->free_area_cache;

        if (map_shared && (TASK_SIZE > 0xfffffffful))
                /*
                 * For 64-bit tasks, align shared segments to 1MB to avoid potential
                 * performance penalty due to virtual aliasing (see ASDM).  For 32-bit
                 * tasks, we prefer to avoid exhausting the address space too quickly by
                 * limiting alignment to a single page.
                 */
                align_mask = SHMLBA - 1;

  full_search:
        start_addr = addr = (addr + align_mask) & ~align_mask;

        for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
                /* At this point:  (!vma || addr < vma->vm_end). */
                if (TASK_SIZE - len < addr || RGN_MAP_LIMIT - len < REGION_OFFSET(addr)) {
                        if (start_addr != TASK_UNMAPPED_BASE) {
                                /* Start a new search --- just in case we missed some holes.  */
                                addr = TASK_UNMAPPED_BASE;
                                goto full_search;
                        }
                        return -ENOMEM;
                }
                if (!vma || addr + len <= vma->vm_start) {
                        /* Remember the address where we stopped this search:  */
                        mm->free_area_cache = addr + len;
                        return addr;
                }
                addr = (vma->vm_end + align_mask) & ~align_mask;
        }
}

asmlinkage long
ia64_getpriority (int which, int who)
{
        long prio;

        prio = sys_getpriority(which, who);
        if (prio >= 0) {
                force_successful_syscall_return();
                prio = 20 - prio;
        }
        return prio;
}

/* XXX obsolete, but leave it here until the old libc is gone... */
asmlinkage unsigned long
sys_getpagesize (void)
{
        return PAGE_SIZE;
}

asmlinkage unsigned long
ia64_brk (unsigned long brk)
{
        unsigned long rlim, retval, newbrk, oldbrk;
        struct mm_struct *mm = current->mm;

        /*
         * Most of this replicates the code in sys_brk() except for an additional safety
         * check and the clearing of r8.  However, we can't call sys_brk() because we need
         * to acquire the mmap_sem before we can do the test...
         */
        down_write(&mm->mmap_sem);

        if (brk < mm->end_code)
                goto out;
        newbrk = PAGE_ALIGN(brk);
        oldbrk = PAGE_ALIGN(mm->brk);
        if (oldbrk == newbrk)
                goto set_brk;

        /* Always allow shrinking brk. */
        if (brk <= mm->brk) {
                if (!do_munmap(mm, newbrk, oldbrk-newbrk))
                        goto set_brk;
                goto out;
        }

        /* Check against unimplemented/unmapped addresses: */
        if ((newbrk - oldbrk) > RGN_MAP_LIMIT || REGION_OFFSET(newbrk) > RGN_MAP_LIMIT)
                goto out;

        /* Check against rlimit.. */
        rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
        if (rlim < RLIM_INFINITY && brk - mm->start_data > rlim)
                goto out;

        /* Check against existing mmap mappings. */
        if (find_vma_intersection(mm, oldbrk, newbrk+PAGE_SIZE))
                goto out;

        /* Ok, looks good - let it rip. */
        if (do_brk(oldbrk, newbrk-oldbrk) != oldbrk)
                goto out;
set_brk:
        mm->brk = brk;
out:
        retval = mm->brk;
        up_write(&mm->mmap_sem);
        force_successful_syscall_return();
        return retval;
}

/*
 * On IA-64, we return the two file descriptors in ret0 and ret1 (r8
 * and r9) as this is faster than doing a copy_to_user().
 */
asmlinkage long
sys_pipe (void)
{
        struct pt_regs *regs = task_pt_regs(current);
        int fd[2];
        int retval;

        retval = do_pipe(fd);
        if (retval)
                goto out;
        retval = fd[0];
        regs->r9 = fd[1];
  out:
        return retval;
}

int ia64_mmap_check(unsigned long addr, unsigned long len,
                unsigned long flags)
{
        unsigned long roff;

        /*
         * Don't permit mappings into unmapped space, the virtual page table
         * of a region, or across a region boundary.  Note: RGN_MAP_LIMIT is
         * equal to 2^n-PAGE_SIZE (for some integer n <= 61) and len > 0.
         */
        roff = REGION_OFFSET(addr);
        if ((len > RGN_MAP_LIMIT) || (roff > (RGN_MAP_LIMIT - len)))
                return -EINVAL;
        return 0;
}

static inline unsigned long
do_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, unsigned long pgoff)
{
        struct file *file = NULL;

        flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
        if (!(flags & MAP_ANONYMOUS)) {
                file = fget(fd);
                if (!file)
                        return -EBADF;

                if (!file->f_op || !file->f_op->mmap) {
                        addr = -ENODEV;
                        goto out;
                }
        }

        /* Careful about overflows.. */
        len = PAGE_ALIGN(len);
        if (!len || len > TASK_SIZE) {
                addr = -EINVAL;
                goto out;
        }

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

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

/*
 * mmap2() is like mmap() except that the offset is expressed in units
 * of PAGE_SIZE (instead of bytes).  This allows to mmap2() (pieces
 * of) files that are larger than the address space of the CPU.
 */
asmlinkage unsigned long
sys_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, long pgoff)
{
        addr = do_mmap2(addr, len, prot, flags, fd, pgoff);
        if (!IS_ERR((void *) addr))
                force_successful_syscall_return();
        return addr;
}

asmlinkage unsigned long
sys_mmap (unsigned long addr, unsigned long len, int prot, int flags, int fd, long off)
{
        if (offset_in_page(off) != 0)
                return -EINVAL;

        addr = do_mmap2(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
        if (!IS_ERR((void *) addr))
                force_successful_syscall_return();
        return addr;
}

asmlinkage unsigned long
ia64_mremap (unsigned long addr, unsigned long old_len, unsigned long new_len, unsigned long flags,
             unsigned long new_addr)
{
        extern unsigned long do_mremap (unsigned long addr,
                                        unsigned long old_len,
                                        unsigned long new_len,
                                        unsigned long flags,
                                        unsigned long new_addr);

        down_write(&current->mm->mmap_sem);
        {
                addr = do_mremap(addr, old_len, new_len, flags, new_addr);
        }
        up_write(&current->mm->mmap_sem);

        if (IS_ERR((void *) addr))
                return addr;

        force_successful_syscall_return();
        return addr;
}

#ifndef CONFIG_PCI

asmlinkage long
sys_pciconfig_read (unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len,
                    void *buf)
{
        return -ENOSYS;
}

asmlinkage long
sys_pciconfig_write (unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len,
                     void *buf)
{
        return -ENOSYS;
}

#endif /* CONFIG_PCI */