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/smp_lock.h>
  17 #include <linux/syscalls.h>
  18 #include <linux/highuid.h>
  19 #include <linux/hugetlb.h>
  20
  21 #include <asm/shmparam.h>
  22 #include <asm/uaccess.h>
  23
  24 unsigned long
  25 arch_get_unmapped_area (struct file *filp, unsigned long addr, unsigned long len,
  26                         unsigned long pgoff, unsigned long flags)
  27 {
  28         long map_shared = (flags & MAP_SHARED);
  29         unsigned long start_addr, align_mask = PAGE_SIZE - 1;
  30         struct mm_struct *mm = current->mm;
  31         struct vm_area_struct *vma;
  32
  33         if (len > RGN_MAP_LIMIT)
  34                 return -ENOMEM;
  35
  36 #ifdef CONFIG_HUGETLB_PAGE
  37         if (REGION_NUMBER(addr) == RGN_HPAGE)
  38                 addr = 0;
  39 #endif
  40         if (!addr)
  41                 addr = mm->free_area_cache;
  42
  43         if (map_shared && (TASK_SIZE > 0xfffffffful))
  44                 /*
  45                  * For 64-bit tasks, align shared segments to 1MB to avoid potential
  46                  * performance penalty due to virtual aliasing (see ASDM).  For 32-bit
  47                  * tasks, we prefer to avoid exhausting the address space too quickly by
  48                  * limiting alignment to a single page.
  49                  */
  50                 align_mask = SHMLBA - 1;
  51
  52   full_search:
  53         start_addr = addr = (addr + align_mask) & ~align_mask;
  54
  55         for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
  56                 /* At this point:  (!vma || addr < vma->vm_end). */
  57                 if (TASK_SIZE - len < addr || RGN_MAP_LIMIT - len < REGION_OFFSET(addr)) {
  58                         if (start_addr != TASK_UNMAPPED_BASE) {
  59                                 /* Start a new search --- just in case we missed some holes.  */
  60                                 addr = TASK_UNMAPPED_BASE;
  61                                 goto full_search;
  62                         }
  63                         return -ENOMEM;
  64                 }
  65                 if (!vma || addr + len <= vma->vm_start) {
  66                         /* Remember the address where we stopped this search:  */
  67                         mm->free_area_cache = addr + len;
  68                         return addr;
  69                 }
  70                 addr = (vma->vm_end + align_mask) & ~align_mask;
  71         }
  72 }
  73
  74 asmlinkage long
  75 ia64_getpriority (int which, int who)
  76 {
  77         long prio;
  78
  79         prio = sys_getpriority(which, who);
  80         if (prio >= 0) {
  81                 force_successful_syscall_return();
  82                 prio = 20 - prio;
  83         }
  84         return prio;
  85 }
  86
  87 /* XXX obsolete, but leave it here until the old libc is gone... */
  88 asmlinkage unsigned long
  89 sys_getpagesize (void)
  90 {
  91         return PAGE_SIZE;
  92 }
  93
  94 asmlinkage unsigned long
  95 ia64_brk (unsigned long brk)
  96 {
  97         unsigned long rlim, retval, newbrk, oldbrk;
  98         struct mm_struct *mm = current->mm;
  99
 100         /*
 101          * Most of this replicates the code in sys_brk() except for an additional safety
 102          * check and the clearing of r8.  However, we can't call sys_brk() because we need
 103          * to acquire the mmap_sem before we can do the test...
 104          */
 105         down_write(&mm->mmap_sem);
 106
 107         if (brk < mm->end_code)
 108                 goto out;
 109         newbrk = PAGE_ALIGN(brk);
 110         oldbrk = PAGE_ALIGN(mm->brk);
 111         if (oldbrk == newbrk)
 112                 goto set_brk;
 113
 114         /* Always allow shrinking brk. */
 115         if (brk <= mm->brk) {
 116                 if (!do_munmap(mm, newbrk, oldbrk-newbrk))
 117                         goto set_brk;
 118                 goto out;
 119         }
 120
 121         /* Check against unimplemented/unmapped addresses: */
 122         if ((newbrk - oldbrk) > RGN_MAP_LIMIT || REGION_OFFSET(newbrk) > RGN_MAP_LIMIT)
 123                 goto out;
 124
 125         /* Check against rlimit.. */
 126         rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
 127         if (rlim < RLIM_INFINITY && brk - mm->start_data > rlim)
 128                 goto out;
 129
 130         /* Check against existing mmap mappings. */
 131         if (find_vma_intersection(mm, oldbrk, newbrk+PAGE_SIZE))
 132                 goto out;
 133
 134         /* Ok, looks good - let it rip. */
 135         if (do_brk(oldbrk, newbrk-oldbrk) != oldbrk)
 136                 goto out;
 137 set_brk:
 138         mm->brk = brk;
 139 out:
 140         retval = mm->brk;
 141         up_write(&mm->mmap_sem);
 142         force_successful_syscall_return();
 143         return retval;
 144 }
 145
 146 /*
 147  * On IA-64, we return the two file descriptors in ret0 and ret1 (r8
 148  * and r9) as this is faster than doing a copy_to_user().
 149  */
 150 asmlinkage long
 151 sys_pipe (void)
 152 {
 153         struct pt_regs *regs = task_pt_regs(current);
 154         int fd[2];
 155         int retval;
 156
 157         retval = do_pipe(fd);
 158         if (retval)
 159                 goto out;
 160         retval = fd[0];
 161         regs->r9 = fd[1];
 162   out:
 163         return retval;
 164 }
 165
 166 int ia64_mmap_check(unsigned long addr, unsigned long len,
 167                 unsigned long flags)
 168 {
 169         unsigned long roff;
 170
 171         /*
 172          * Don't permit mappings into unmapped space, the virtual page table
 173          * of a region, or across a region boundary.  Note: RGN_MAP_LIMIT is
 174          * equal to 2^n-PAGE_SIZE (for some integer n <= 61) and len > 0.
 175          */
 176         roff = REGION_OFFSET(addr);
 177         if ((len > RGN_MAP_LIMIT) || (roff > (RGN_MAP_LIMIT - len)))
 178                 return -EINVAL;
 179         return 0;
 180 }
 181
 182 static inline unsigned long
 183 do_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, unsigned long pgoff)
 184 {
 185         struct file *file = NULL;
 186
 187         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 188         if (!(flags & MAP_ANONYMOUS)) {
 189                 file = fget(fd);
 190                 if (!file)
 191                         return -EBADF;
 192
 193                 if (!file->f_op || !file->f_op->mmap) {
 194                         addr = -ENODEV;
 195                         goto out;
 196                 }
 197         }
 198
 199         /* Careful about overflows.. */
 200         len = PAGE_ALIGN(len);
 201         if (!len || len > TASK_SIZE) {
 202                 addr = -EINVAL;
 203                 goto out;
 204         }
 205
 206         down_write(&current->mm->mmap_sem);
 207         addr = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
 208         up_write(&current->mm->mmap_sem);
 209
 210 out:    if (file)
 211                 fput(file);
 212         return addr;
 213 }
 214
 215 /*
 216  * mmap2() is like mmap() except that the offset is expressed in units
 217  * of PAGE_SIZE (instead of bytes).  This allows to mmap2() (pieces
 218  * of) files that are larger than the address space of the CPU.
 219  */
 220 asmlinkage unsigned long
 221 sys_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, long pgoff)
 222 {
 223         addr = do_mmap2(addr, len, prot, flags, fd, pgoff);
 224         if (!IS_ERR((void *) addr))
 225                 force_successful_syscall_return();
 226         return addr;
 227 }
 228
 229 asmlinkage unsigned long
 230 sys_mmap (unsigned long addr, unsigned long len, int prot, int flags, int fd, long off)
 231 {
 232         if (offset_in_page(off) != 0)
 233                 return -EINVAL;
 234
 235         addr = do_mmap2(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
 236         if (!IS_ERR((void *) addr))
 237                 force_successful_syscall_return();
 238         return addr;
 239 }
 240
 241 asmlinkage unsigned long
 242 ia64_mremap (unsigned long addr, unsigned long old_len, unsigned long new_len, unsigned long flags,
 243              unsigned long new_addr)
 244 {
 245         extern unsigned long do_mremap (unsigned long addr,
 246                                         unsigned long old_len,
 247                                         unsigned long new_len,
 248                                         unsigned long flags,
 249                                         unsigned long new_addr);
 250
 251         down_write(&current->mm->mmap_sem);
 252         {
 253                 addr = do_mremap(addr, old_len, new_len, flags, new_addr);
 254         }
 255         up_write(&current->mm->mmap_sem);
 256
 257         if (IS_ERR((void *) addr))
 258                 return addr;
 259
 260         force_successful_syscall_return();
 261         return addr;
 262 }
 263
 264 #ifndef CONFIG_PCI
 265
 266 asmlinkage long
 267 sys_pciconfig_read (unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len,
 268                     void *buf)
 269 {
 270         return -ENOSYS;
 271 }
 272
 273 asmlinkage long
 274 sys_pciconfig_write (unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len,
 275                      void *buf)
 276 {
 277         return -ENOSYS;
 278 }
 279
 280 #endif /* CONFIG_PCI */