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 rlim, retval, newbrk, oldbrk;
 104         struct mm_struct *mm = current->mm;
 105
 106         /*
 107          * Most of this replicates the code in sys_brk() except for an additional safety
 108          * check and the clearing of r8.  However, we can't call sys_brk() because we need
 109          * to acquire the mmap_sem before we can do the test...
 110          */
 111         down_write(&mm->mmap_sem);
 112
 113         if (brk < mm->end_code)
 114                 goto out;
 115         newbrk = PAGE_ALIGN(brk);
 116         oldbrk = PAGE_ALIGN(mm->brk);
 117         if (oldbrk == newbrk)
 118                 goto set_brk;
 119
 120         /* Always allow shrinking brk. */
 121         if (brk <= mm->brk) {
 122                 if (!do_munmap(mm, newbrk, oldbrk-newbrk))
 123                         goto set_brk;
 124                 goto out;
 125         }
 126
 127         /* Check against unimplemented/unmapped addresses: */
 128         if ((newbrk - oldbrk) > RGN_MAP_LIMIT || REGION_OFFSET(newbrk) > RGN_MAP_LIMIT)
 129                 goto out;
 130
 131         /* Check against rlimit.. */
 132         rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
 133         if (rlim < RLIM_INFINITY && brk - mm->start_data > rlim)
 134                 goto out;
 135
 136         /* Check against existing mmap mappings. */
 137         if (find_vma_intersection(mm, oldbrk, newbrk+PAGE_SIZE))
 138                 goto out;
 139
 140         /* Ok, looks good - let it rip. */
 141         if (do_brk(oldbrk, newbrk-oldbrk) != oldbrk)
 142                 goto out;
 143 set_brk:
 144         mm->brk = brk;
 145 out:
 146         retval = mm->brk;
 147         up_write(&mm->mmap_sem);
 148         force_successful_syscall_return();
 149         return retval;
 150 }
 151
 152 /*
 153  * On IA-64, we return the two file descriptors in ret0 and ret1 (r8
 154  * and r9) as this is faster than doing a copy_to_user().
 155  */
 156 asmlinkage long
 157 sys_pipe (void)
 158 {
 159         struct pt_regs *regs = task_pt_regs(current);
 160         int fd[2];
 161         int retval;
 162
 163         retval = do_pipe(fd);
 164         if (retval)
 165                 goto out;
 166         retval = fd[0];
 167         regs->r9 = fd[1];
 168   out:
 169         return retval;
 170 }
 171
 172 int ia64_mmap_check(unsigned long addr, unsigned long len,
 173                 unsigned long flags)
 174 {
 175         unsigned long roff;
 176
 177         /*
 178          * Don't permit mappings into unmapped space, the virtual page table
 179          * of a region, or across a region boundary.  Note: RGN_MAP_LIMIT is
 180          * equal to 2^n-PAGE_SIZE (for some integer n <= 61) and len > 0.
 181          */
 182         roff = REGION_OFFSET(addr);
 183         if ((len > RGN_MAP_LIMIT) || (roff > (RGN_MAP_LIMIT - len)))
 184                 return -EINVAL;
 185         return 0;
 186 }
 187
 188 static inline unsigned long
 189 do_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, unsigned long pgoff)
 190 {
 191         struct file *file = NULL;
 192
 193         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 194         if (!(flags & MAP_ANONYMOUS)) {
 195                 file = fget(fd);
 196                 if (!file)
 197                         return -EBADF;
 198
 199                 if (!file->f_op || !file->f_op->mmap) {
 200                         addr = -ENODEV;
 201                         goto out;
 202                 }
 203         }
 204
 205         /* Careful about overflows.. */
 206         len = PAGE_ALIGN(len);
 207         if (!len || len > TASK_SIZE) {
 208                 addr = -EINVAL;
 209                 goto out;
 210         }
 211
 212         down_write(&current->mm->mmap_sem);
 213         addr = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
 214         up_write(&current->mm->mmap_sem);
 215
 216 out:    if (file)
 217                 fput(file);
 218         return addr;
 219 }
 220
 221 /*
 222  * mmap2() is like mmap() except that the offset is expressed in units
 223  * of PAGE_SIZE (instead of bytes).  This allows to mmap2() (pieces
 224  * of) files that are larger than the address space of the CPU.
 225  */
 226 asmlinkage unsigned long
 227 sys_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, long pgoff)
 228 {
 229         addr = do_mmap2(addr, len, prot, flags, fd, pgoff);
 230         if (!IS_ERR((void *) addr))
 231                 force_successful_syscall_return();
 232         return addr;
 233 }
 234
 235 asmlinkage unsigned long
 236 sys_mmap (unsigned long addr, unsigned long len, int prot, int flags, int fd, long off)
 237 {
 238         if (offset_in_page(off) != 0)
 239                 return -EINVAL;
 240
 241         addr = do_mmap2(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
 242         if (!IS_ERR((void *) addr))
 243                 force_successful_syscall_return();
 244         return addr;
 245 }
 246
 247 asmlinkage unsigned long
 248 ia64_mremap (unsigned long addr, unsigned long old_len, unsigned long new_len, unsigned long flags,
 249              unsigned long new_addr)
 250 {
 251         extern unsigned long do_mremap (unsigned long addr,
 252                                         unsigned long old_len,
 253                                         unsigned long new_len,
 254                                         unsigned long flags,
 255                                         unsigned long new_addr);
 256
 257         down_write(&current->mm->mmap_sem);
 258         {
 259                 addr = do_mremap(addr, old_len, new_len, flags, new_addr);
 260         }
 261         up_write(&current->mm->mmap_sem);
 262
 263         if (IS_ERR((void *) addr))
 264                 return addr;
 265
 266         force_successful_syscall_return();
 267         return addr;
 268 }
 269
 270 #ifndef CONFIG_PCI
 271
 272 asmlinkage long
 273 sys_pciconfig_read (unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len,
 274                     void *buf)
 275 {
 276         return -ENOSYS;
 277 }
 278
 279 asmlinkage long
 280 sys_pciconfig_write (unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len,
 281                      void *buf)
 282 {
 283         return -ENOSYS;
 284 }
 285
 286 #endif /* CONFIG_PCI */