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/config.h>
   9 #include <linux/errno.h>
  10 #include <linux/fs.h>
  11 #include <linux/mm.h>
  12 #include <linux/mman.h>
  13 #include <linux/sched.h>
  14 #include <linux/shm.h>
  15 #include <linux/file.h>         /* doh, must come after sched.h... */
  16 #include <linux/smp.h>
  17 #include <linux/smp_lock.h>
  18 #include <linux/syscalls.h>
  19 #include <linux/highuid.h>
  20 #include <linux/hugetlb.h>
  21
  22 #include <asm/shmparam.h>
  23 #include <asm/uaccess.h>
  24
  25 unsigned long
  26 arch_get_unmapped_area (struct file *filp, unsigned long addr, unsigned long len,
  27                         unsigned long pgoff, unsigned long flags)
  28 {
  29         long map_shared = (flags & MAP_SHARED);
  30         unsigned long start_addr, align_mask = PAGE_SIZE - 1;
  31         struct mm_struct *mm = current->mm;
  32         struct vm_area_struct *vma;
  33
  34         if (len > RGN_MAP_LIMIT)
  35                 return -ENOMEM;
  36
  37 #ifdef CONFIG_HUGETLB_PAGE
  38         if (REGION_NUMBER(addr) == REGION_HPAGE)
  39                 addr = 0;
  40 #endif
  41         if (!addr)
  42                 addr = mm->free_area_cache;
  43
  44         if (map_shared && (TASK_SIZE > 0xfffffffful))
  45                 /*
  46                  * For 64-bit tasks, align shared segments to 1MB to avoid potential
  47                  * performance penalty due to virtual aliasing (see ASDM).  For 32-bit
  48                  * tasks, we prefer to avoid exhausting the address space too quickly by
  49                  * limiting alignment to a single page.
  50                  */
  51                 align_mask = SHMLBA - 1;
  52
  53   full_search:
  54         start_addr = addr = (addr + align_mask) & ~align_mask;
  55
  56         for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
  57                 /* At this point:  (!vma || addr < vma->vm_end). */
  58                 if (TASK_SIZE - len < addr || RGN_MAP_LIMIT - len < REGION_OFFSET(addr)) {
  59                         if (start_addr != TASK_UNMAPPED_BASE) {
  60                                 /* Start a new search --- just in case we missed some holes.  */
  61                                 addr = TASK_UNMAPPED_BASE;
  62                                 goto full_search;
  63                         }
  64                         return -ENOMEM;
  65                 }
  66                 if (!vma || addr + len <= vma->vm_start) {
  67                         /* Remember the address where we stopped this search:  */
  68                         mm->free_area_cache = addr + len;
  69                         return addr;
  70                 }
  71                 addr = (vma->vm_end + align_mask) & ~align_mask;
  72         }
  73 }
  74
  75 asmlinkage long
  76 ia64_getpriority (int which, int who)
  77 {
  78         long prio;
  79
  80         prio = sys_getpriority(which, who);
  81         if (prio >= 0) {
  82                 force_successful_syscall_return();
  83                 prio = 20 - prio;
  84         }
  85         return prio;
  86 }
  87
  88 /* XXX obsolete, but leave it here until the old libc is gone... */
  89 asmlinkage unsigned long
  90 sys_getpagesize (void)
  91 {
  92         return PAGE_SIZE;
  93 }
  94
  95 asmlinkage unsigned long
  96 ia64_shmat (int shmid, void __user *shmaddr, int shmflg)
  97 {
  98         unsigned long raddr;
  99         int retval;
 100
 101         retval = do_shmat(shmid, shmaddr, shmflg, &raddr);
 102         if (retval < 0)
 103                 return retval;
 104
 105         force_successful_syscall_return();
 106         return raddr;
 107 }
 108
 109 asmlinkage unsigned long
 110 ia64_brk (unsigned long brk)
 111 {
 112         unsigned long rlim, retval, newbrk, oldbrk;
 113         struct mm_struct *mm = current->mm;
 114
 115         /*
 116          * Most of this replicates the code in sys_brk() except for an additional safety
 117          * check and the clearing of r8.  However, we can't call sys_brk() because we need
 118          * to acquire the mmap_sem before we can do the test...
 119          */
 120         down_write(&mm->mmap_sem);
 121
 122         if (brk < mm->end_code)
 123                 goto out;
 124         newbrk = PAGE_ALIGN(brk);
 125         oldbrk = PAGE_ALIGN(mm->brk);
 126         if (oldbrk == newbrk)
 127                 goto set_brk;
 128
 129         /* Always allow shrinking brk. */
 130         if (brk <= mm->brk) {
 131                 if (!do_munmap(mm, newbrk, oldbrk-newbrk))
 132                         goto set_brk;
 133                 goto out;
 134         }
 135
 136         /* Check against unimplemented/unmapped addresses: */
 137         if ((newbrk - oldbrk) > RGN_MAP_LIMIT || REGION_OFFSET(newbrk) > RGN_MAP_LIMIT)
 138                 goto out;
 139
 140         /* Check against rlimit.. */
 141         rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
 142         if (rlim < RLIM_INFINITY && brk - mm->start_data > rlim)
 143                 goto out;
 144
 145         /* Check against existing mmap mappings. */
 146         if (find_vma_intersection(mm, oldbrk, newbrk+PAGE_SIZE))
 147                 goto out;
 148
 149         /* Ok, looks good - let it rip. */
 150         if (do_brk(oldbrk, newbrk-oldbrk) != oldbrk)
 151                 goto out;
 152 set_brk:
 153         mm->brk = brk;
 154 out:
 155         retval = mm->brk;
 156         up_write(&mm->mmap_sem);
 157         force_successful_syscall_return();
 158         return retval;
 159 }
 160
 161 /*
 162  * On IA-64, we return the two file descriptors in ret0 and ret1 (r8
 163  * and r9) as this is faster than doing a copy_to_user().
 164  */
 165 asmlinkage long
 166 sys_pipe (void)
 167 {
 168         struct pt_regs *regs = ia64_task_regs(current);
 169         int fd[2];
 170         int retval;
 171
 172         retval = do_pipe(fd);
 173         if (retval)
 174                 goto out;
 175         retval = fd[0];
 176         regs->r9 = fd[1];
 177   out:
 178         return retval;
 179 }
 180
 181 static inline unsigned long
 182 do_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, unsigned long pgoff)
 183 {
 184         unsigned long roff;
 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         /*
 200          * A zero mmap always succeeds in Linux, independent of whether or not the
 201          * remaining arguments are valid.
 202          */
 203         if (len == 0)
 204                 goto out;
 205
 206         /* Careful about overflows.. */
 207         len = PAGE_ALIGN(len);
 208         if (!len || len > TASK_SIZE) {
 209                 addr = -EINVAL;
 210                 goto out;
 211         }
 212
 213         /*
 214          * Don't permit mappings into unmapped space, the virtual page table of a region,
 215          * or across a region boundary.  Note: RGN_MAP_LIMIT is equal to 2^n-PAGE_SIZE
 216          * (for some integer n <= 61) and len > 0.
 217          */
 218         roff = REGION_OFFSET(addr);
 219         if ((len > RGN_MAP_LIMIT) || (roff > (RGN_MAP_LIMIT - len))) {
 220                 addr = -EINVAL;
 221                 goto out;
 222         }
 223
 224         down_write(&current->mm->mmap_sem);
 225         addr = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
 226         up_write(&current->mm->mmap_sem);
 227
 228 out:    if (file)
 229                 fput(file);
 230         return addr;
 231 }
 232
 233 /*
 234  * mmap2() is like mmap() except that the offset is expressed in units
 235  * of PAGE_SIZE (instead of bytes).  This allows to mmap2() (pieces
 236  * of) files that are larger than the address space of the CPU.
 237  */
 238 asmlinkage unsigned long
 239 sys_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, long pgoff)
 240 {
 241         addr = do_mmap2(addr, len, prot, flags, fd, pgoff);
 242         if (!IS_ERR((void *) addr))
 243                 force_successful_syscall_return();
 244         return addr;
 245 }
 246
 247 asmlinkage unsigned long
 248 sys_mmap (unsigned long addr, unsigned long len, int prot, int flags, int fd, long off)
 249 {
 250         if (offset_in_page(off) != 0)
 251                 return -EINVAL;
 252
 253         addr = do_mmap2(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
 254         if (!IS_ERR((void *) addr))
 255                 force_successful_syscall_return();
 256         return addr;
 257 }
 258
 259 asmlinkage unsigned long
 260 ia64_mremap (unsigned long addr, unsigned long old_len, unsigned long new_len, unsigned long flags,
 261              unsigned long new_addr)
 262 {
 263         extern unsigned long do_mremap (unsigned long addr,
 264                                         unsigned long old_len,
 265                                         unsigned long new_len,
 266                                         unsigned long flags,
 267                                         unsigned long new_addr);
 268
 269         down_write(&current->mm->mmap_sem);
 270         {
 271                 addr = do_mremap(addr, old_len, new_len, flags, new_addr);
 272         }
 273         up_write(&current->mm->mmap_sem);
 274
 275         if (IS_ERR((void *) addr))
 276                 return addr;
 277
 278         force_successful_syscall_return();
 279         return addr;
 280 }
 281
 282 #ifndef CONFIG_PCI
 283
 284 asmlinkage long
 285 sys_pciconfig_read (unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len,
 286                     void *buf)
 287 {
 288         return -ENOSYS;
 289 }
 290
 291 asmlinkage long
 292 sys_pciconfig_write (unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len,
 293                      void *buf)
 294 {
 295         return -ENOSYS;
 296 }
 297
 298 #endif /* CONFIG_PCI */