arch/ia64/kernel/sys_ia64.c

   1 /*
   2  * This file contains various system calls that have different calling
   3  * conventions on different platforms.
   4  *
   5  * Copyright (C) 1999-2000, 2002-2003, 2005 Hewlett-Packard Co
   6  *      David Mosberger-Tang <davidm@hpl.hp.com>
   7  */
   8 #include <linux/errno.h>
   9 #include <linux/fs.h>
  10 #include <linux/mm.h>
  11 #include <linux/mman.h>
  12 #include <linux/sched.h>
  13 #include <linux/shm.h>
  14 #include <linux/file.h>         /* doh, must come after sched.h... */
  15 #include <linux/smp.h>
  16 #include <linux/syscalls.h>
  17 #include <linux/highuid.h>
  18 #include <linux/hugetlb.h>
  19
  20 #include <asm/shmparam.h>
  21 #include <asm/uaccess.h>
  22
  23 unsigned long
  24 arch_get_unmapped_area (struct file *filp, unsigned long addr, unsigned long len,
  25                         unsigned long pgoff, unsigned long flags)
  26 {
  27         long map_shared = (flags & MAP_SHARED);
  28         unsigned long start_addr, align_mask = PAGE_SIZE - 1;
  29         struct mm_struct *mm = current->mm;
  30         struct vm_area_struct *vma;
  31
  32         if (len > RGN_MAP_LIMIT)
  33                 return -ENOMEM;
  34
  35         /* handle fixed mapping: prevent overlap with huge pages */
  36         if (flags & MAP_FIXED) {
  37                 if (is_hugepage_only_range(mm, addr, len))
  38                         return -EINVAL;
  39                 return addr;
  40         }
  41
  42 #ifdef CONFIG_HUGETLB_PAGE
  43         if (REGION_NUMBER(addr) == RGN_HPAGE)
  44                 addr = 0;
  45 #endif
  46         if (!addr)
  47                 addr = mm->free_area_cache;
  48
  49         if (map_shared && (TASK_SIZE > 0xfffffffful))
  50                 /*
  51                  * For 64-bit tasks, align shared segments to 1MB to avoid potential
  52                  * performance penalty due to virtual aliasing (see ASDM).  For 32-bit
  53                  * tasks, we prefer to avoid exhausting the address space too quickly by
  54                  * limiting alignment to a single page.
  55                  */
  56                 align_mask = SHMLBA - 1;
  57
  58   full_search:
  59         start_addr = addr = (addr + align_mask) & ~align_mask;
  60
  61         for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
  62                 /* At this point:  (!vma || addr < vma->vm_end). */
  63                 if (TASK_SIZE - len < addr || RGN_MAP_LIMIT - len < REGION_OFFSET(addr)) {
  64                         if (start_addr != TASK_UNMAPPED_BASE) {
  65                                 /* Start a new search --- just in case we missed some holes.  */
  66                                 addr = TASK_UNMAPPED_BASE;
  67                                 goto full_search;
  68                         }
  69                         return -ENOMEM;
  70                 }
  71                 if (!vma || addr + len <= vma->vm_start) {
  72                         /* Remember the address where we stopped this search:  */
  73                         mm->free_area_cache = addr + len;
  74                         return addr;
  75                 }
  76                 addr = (vma->vm_end + align_mask) & ~align_mask;
  77         }
  78 }
  79
  80 asmlinkage long
  81 ia64_getpriority (int which, int who)
  82 {
  83         long prio;
  84
  85         prio = sys_getpriority(which, who);
  86         if (prio >= 0) {
  87                 force_successful_syscall_return();
  88                 prio = 20 - prio;
  89         }
  90         return prio;
  91 }
  92
  93 /* XXX obsolete, but leave it here until the old libc is gone... */
  94 asmlinkage unsigned long
  95 sys_getpagesize (void)
  96 {
  97         return PAGE_SIZE;
  98 }
  99
 100 asmlinkage unsigned long
 101 ia64_brk (unsigned long brk)
 102 {
 103         unsigned long retval = sys_brk(brk);
 104         force_successful_syscall_return();
 105         return retval;
 106 }
 107
 108 /*
 109  * On IA-64, we return the two file descriptors in ret0 and ret1 (r8
 110  * and r9) as this is faster than doing a copy_to_user().
 111  */
 112 asmlinkage long
 113 sys_ia64_pipe (void)
 114 {
 115         struct pt_regs *regs = task_pt_regs(current);
 116         int fd[2];
 117         int retval;
 118
 119         retval = do_pipe_flags(fd, 0);
 120         if (retval)
 121                 goto out;
 122         retval = fd[0];
 123         regs->r9 = fd[1];
 124   out:
 125         return retval;
 126 }
 127
 128 int ia64_mmap_check(unsigned long addr, unsigned long len,
 129                 unsigned long flags)
 130 {
 131         unsigned long roff;
 132
 133         /*
 134          * Don't permit mappings into unmapped space, the virtual page table
 135          * of a region, or across a region boundary.  Note: RGN_MAP_LIMIT is
 136          * equal to 2^n-PAGE_SIZE (for some integer n <= 61) and len > 0.
 137          */
 138         roff = REGION_OFFSET(addr);
 139         if ((len > RGN_MAP_LIMIT) || (roff > (RGN_MAP_LIMIT - len)))
 140                 return -EINVAL;
 141         return 0;
 142 }
 143
 144 /*
 145  * mmap2() is like mmap() except that the offset is expressed in units
 146  * of PAGE_SIZE (instead of bytes).  This allows to mmap2() (pieces
 147  * of) files that are larger than the address space of the CPU.
 148  */
 149 asmlinkage unsigned long
 150 sys_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, long pgoff)
 151 {
 152         addr = sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff);
 153         if (!IS_ERR((void *) addr))
 154                 force_successful_syscall_return();
 155         return addr;
 156 }
 157
 158 asmlinkage unsigned long
 159 sys_mmap (unsigned long addr, unsigned long len, int prot, int flags, int fd, long off)
 160 {
 161         if (offset_in_page(off) != 0)
 162                 return -EINVAL;
 163
 164         addr = sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
 165         if (!IS_ERR((void *) addr))
 166                 force_successful_syscall_return();
 167         return addr;
 168 }
 169
 170 asmlinkage unsigned long
 171 ia64_mremap (unsigned long addr, unsigned long old_len, unsigned long new_len, unsigned long flags,
 172              unsigned long new_addr)
 173 {
 174         extern unsigned long do_mremap (unsigned long addr,
 175                                         unsigned long old_len,
 176                                         unsigned long new_len,
 177                                         unsigned long flags,
 178                                         unsigned long new_addr);
 179
 180         down_write(&current->mm->mmap_sem);
 181         {
 182                 addr = do_mremap(addr, old_len, new_len, flags, new_addr);
 183         }
 184         up_write(&current->mm->mmap_sem);
 185
 186         if (IS_ERR((void *) addr))
 187                 return addr;
 188
 189         force_successful_syscall_return();
 190         return addr;
 191 }
 192
 193 #ifndef CONFIG_PCI
 194
 195 asmlinkage long
 196 sys_pciconfig_read (unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len,
 197                     void *buf)
 198 {
 199         return -ENOSYS;
 200 }
 201
 202 asmlinkage long
 203 sys_pciconfig_write (unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len,
 204                      void *buf)
 205 {
 206         return -ENOSYS;
 207 }
 208
 209 #endif /* CONFIG_PCI */