arch/um/kernel/tt/include/uaccess.h

   1 /*
   2  * Copyright (C) 2000, 2001 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #ifndef __TT_UACCESS_H
   7 #define __TT_UACCESS_H
   8
   9 #include "linux/string.h"
  10 #include "linux/sched.h"
  11 #include "asm/processor.h"
  12 #include "asm/errno.h"
  13 #include "asm/current.h"
  14 #include "asm/a.out.h"
  15 #include "uml_uaccess.h"
  16
  17 #define ABOVE_KMEM (16 * 1024 * 1024)
  18
  19 extern unsigned long end_vm;
  20 extern unsigned long uml_physmem;
  21
  22 #define under_task_size(addr, size) \
  23         (((unsigned long) (addr) < TASK_SIZE) && \
  24          (((unsigned long) (addr) + (size)) < TASK_SIZE))
  25
  26 #define is_stack(addr, size) \
  27         (((unsigned long) (addr) < STACK_TOP) && \
  28          ((unsigned long) (addr) >= STACK_TOP - ABOVE_KMEM) && \
  29          (((unsigned long) (addr) + (size)) <= STACK_TOP))
  30
  31 #define access_ok_tt(type, addr, size) \
  32         ((type == VERIFY_READ) || (segment_eq(get_fs(), KERNEL_DS)) || \
  33          (((unsigned long) (addr) <= ((unsigned long) (addr) + (size))) && \
  34           (under_task_size(addr, size) || is_stack(addr, size))))
  35
  36 static inline int verify_area_tt(int type, const void * addr,
  37                                  unsigned long size)
  38 {
  39         return(access_ok_tt(type, addr, size) ? 0 : -EFAULT);
  40 }
  41
  42 extern unsigned long get_fault_addr(void);
  43
  44 extern int __do_copy_from_user(void *to, const void *from, int n,
  45                                void **fault_addr, void **fault_catcher);
  46
  47 static inline int copy_from_user_tt(void *to, const void *from, int n)
  48 {
  49         return(access_ok_tt(VERIFY_READ, from, n) ?
  50                __do_copy_from_user(to, from, n,
  51                                    &current->thread.fault_addr,
  52                                    &current->thread.fault_catcher) : n);
  53 }
  54
  55 static inline int copy_to_user_tt(void *to, const void *from, int n)
  56 {
  57         return(access_ok_tt(VERIFY_WRITE, to, n) ?
  58                __do_copy_to_user(to, from, n,
  59                                    &current->thread.fault_addr,
  60                                    &current->thread.fault_catcher) : n);
  61 }
  62
  63 extern int __do_strncpy_from_user(char *dst, const char *src, size_t n,
  64                                   void **fault_addr, void **fault_catcher);
  65
  66 static inline int strncpy_from_user_tt(char *dst, const char *src, int count)
  67 {
  68         int n;
  69
  70         if(!access_ok_tt(VERIFY_READ, src, 1)) return(-EFAULT);
  71         n = __do_strncpy_from_user(dst, src, count,
  72                                    &current->thread.fault_addr,
  73                                    &current->thread.fault_catcher);
  74         if(n < 0) return(-EFAULT);
  75         return(n);
  76 }
  77
  78 extern int __do_clear_user(void *mem, size_t len, void **fault_addr,
  79                            void **fault_catcher);
  80
  81 static inline int __clear_user_tt(void *mem, int len)
  82 {
  83         return(__do_clear_user(mem, len,
  84                                &current->thread.fault_addr,
  85                                &current->thread.fault_catcher));
  86 }
  87
  88 static inline int clear_user_tt(void *mem, int len)
  89 {
  90         return(access_ok_tt(VERIFY_WRITE, mem, len) ?
  91                __do_clear_user(mem, len,
  92                                &current->thread.fault_addr,
  93                                &current->thread.fault_catcher) : len);
  94 }
  95
  96 extern int __do_strnlen_user(const char *str, unsigned long n,
  97                              void **fault_addr, void **fault_catcher);
  98
  99 static inline int strnlen_user_tt(const void *str, int len)
 100 {
 101         return(__do_strnlen_user(str, len,
 102                                  &current->thread.fault_addr,
 103                                  &current->thread.fault_catcher));
 104 }
 105
 106 #endif
 107
 108 /*
 109  * Overrides for Emacs so that we follow Linus's tabbing style.
 110  * Emacs will notice this stuff at the end of the file and automatically
 111  * adjust the settings for this buffer only.  This must remain at the end
 112  * of the file.
 113  * ---------------------------------------------------------------------------
 114  * Local variables:
 115  * c-file-style: "linux"
 116  * End:
 117  */