arch/tile/kernel/compat.c

   1 /*
   2  * Copyright 2010 Tilera Corporation. All Rights Reserved.
   3  *
   4  *   This program is free software; you can redistribute it and/or
   5  *   modify it under the terms of the GNU General Public License
   6  *   as published by the Free Software Foundation, version 2.
   7  *
   8  *   This program is distributed in the hope that it will be useful, but
   9  *   WITHOUT ANY WARRANTY; without even the implied warranty of
  10  *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  11  *   NON INFRINGEMENT.  See the GNU General Public License for
  12  *   more details.
  13  */
  14
  15 /* Adjust unistd.h to provide 32-bit numbers and functions. */
  16 #define __SYSCALL_COMPAT
  17
  18 #include <linux/compat.h>
  19 #include <linux/syscalls.h>
  20 #include <linux/kdev_t.h>
  21 #include <linux/fs.h>
  22 #include <linux/fcntl.h>
  23 #include <linux/uaccess.h>
  24 #include <linux/signal.h>
  25 #include <asm/syscalls.h>
  26 #include <asm/byteorder.h>
  27
  28 /*
  29  * Syscalls that take 64-bit numbers traditionally take them in 32-bit
  30  * "high" and "low" value parts on 32-bit architectures.
  31  * In principle, one could imagine passing some register arguments as
  32  * fully 64-bit on TILE-Gx in 32-bit mode, but it seems easier to
  33  * adopt the usual convention.
  34  */
  35
  36 #ifdef __BIG_ENDIAN
  37 #define SYSCALL_PAIR(name) u32, name ## _hi, u32, name ## _lo
  38 #else
  39 #define SYSCALL_PAIR(name) u32, name ## _lo, u32, name ## _hi
  40 #endif
  41
  42 COMPAT_SYSCALL_DEFINE4(truncate64, char __user *, filename, u32, dummy,
  43                        SYSCALL_PAIR(length))
  44 {
  45         return sys_truncate(filename, ((loff_t)length_hi << 32) | length_lo);
  46 }
  47
  48 COMPAT_SYSCALL_DEFINE4(ftruncate64, unsigned int, fd, u32, dummy,
  49                        SYSCALL_PAIR(length))
  50 {
  51         return sys_ftruncate(fd, ((loff_t)length_hi << 32) | length_lo);
  52 }
  53
  54 COMPAT_SYSCALL_DEFINE6(pread64, unsigned int, fd, char __user *, ubuf,
  55                        size_t, count, u32, dummy, SYSCALL_PAIR(offset))
  56 {
  57         return sys_pread64(fd, ubuf, count,
  58                            ((loff_t)offset_hi << 32) | offset_lo);
  59 }
  60
  61 COMPAT_SYSCALL_DEFINE6(pwrite64, unsigned int, fd, char __user *, ubuf,
  62                        size_t, count, u32, dummy, SYSCALL_PAIR(offset))
  63 {
  64         return sys_pwrite64(fd, ubuf, count,
  65                             ((loff_t)offset_hi << 32) | offset_lo);
  66 }
  67
  68 COMPAT_SYSCALL_DEFINE6(sync_file_range2, int, fd, unsigned int, flags,
  69                        SYSCALL_PAIR(offset), SYSCALL_PAIR(nbytes))
  70 {
  71         return sys_sync_file_range(fd, ((loff_t)offset_hi << 32) | offset_lo,
  72                                    ((loff_t)nbytes_hi << 32) | nbytes_lo,
  73                                    flags);
  74 }
  75
  76 COMPAT_SYSCALL_DEFINE6(fallocate, int, fd, int, mode,
  77                        SYSCALL_PAIR(offset), SYSCALL_PAIR(len))
  78 {
  79         return sys_fallocate(fd, mode, ((loff_t)offset_hi << 32) | offset_lo,
  80                              ((loff_t)len_hi << 32) | len_lo);
  81 }
  82
  83 /*
  84  * Avoid bug in generic sys_llseek() that specifies offset_high and
  85  * offset_low as "unsigned long", thus making it possible to pass
  86  * a sign-extended high 32 bits in offset_low.
  87  * Note that we do not use SYSCALL_PAIR here since glibc passes the
  88  * high and low parts explicitly in that order.
  89  */
  90 COMPAT_SYSCALL_DEFINE5(llseek, unsigned int, fd, unsigned int, offset_high,
  91                        unsigned int, offset_low, loff_t __user *, result,
  92                        unsigned int, origin)
  93 {
  94         return sys_llseek(fd, offset_high, offset_low, result, origin);
  95 }
  96
  97 /* Provide the compat syscall number to call mapping. */
  98 #undef __SYSCALL
  99 #define __SYSCALL(nr, call) [nr] = (call),
 100
 101 /* See comments in sys.c */
 102 #define compat_sys_fadvise64_64 sys32_fadvise64_64
 103 #define compat_sys_readahead sys32_readahead
 104 #define sys_llseek compat_sys_llseek
 105
 106 /* Call the assembly trampolines where necessary. */
 107 #define compat_sys_rt_sigreturn _compat_sys_rt_sigreturn
 108 #define sys_clone _sys_clone
 109
 110 /*
 111  * Note that we can't include <linux/unistd.h> here since the header
 112  * guard will defeat us; <asm/unistd.h> checks for __SYSCALL as well.
 113  */
 114 void *compat_sys_call_table[__NR_syscalls] = {
 115         [0 ... __NR_syscalls-1] = sys_ni_syscall,
 116 #include <asm/unistd.h>
 117 };