1#ifndef __M68KNOMMU_UACCESS_H 2#define __M68KNOMMU_UACCESS_H 3 4/* 5 * User space memory access functions 6 */ 7#include <linux/sched.h> 8#include <linux/mm.h> 9#include <linux/string.h> 10 11#include <asm/segment.h> 12 13#define VERIFY_READ 0 14#define VERIFY_WRITE 1 15 16#define access_ok(type,addr,size) _access_ok((unsigned long)(addr),(size)) 17 18/* 19 * It is not enough to just have access_ok check for a real RAM address. 20 * This would disallow the case of code/ro-data running XIP in flash/rom. 21 * Ideally we would check the possible flash ranges too, but that is 22 * currently not so easy. 23 */ 24static inline int _access_ok(unsigned long addr, unsigned long size) 25{ 26 return 1; 27} 28 29/* 30 * The exception table consists of pairs of addresses: the first is the 31 * address of an instruction that is allowed to fault, and the second is 32 * the address at which the program should continue. No registers are 33 * modified, so it is entirely up to the continuation code to figure out 34 * what to do. 35 * 36 * All the routines below use bits of fixup code that are out of line 37 * with the main instruction path. This means when everything is well, 38 * we don't even have to jump over them. Further, they do not intrude 39 * on our cache or tlb entries. 40 */ 41 42struct exception_table_entry 43{ 44 unsigned long insn, fixup; 45}; 46 47/* Returns 0 if exception not found and fixup otherwise. */ 48extern unsigned long search_exception_table(unsigned long); 49 50 51/* 52 * These are the main single-value transfer routines. They automatically 53 * use the right size if we just have the right pointer type. 54 */ 55 56#define put_user(x, ptr) \ 57({ \ 58 int __pu_err = 0; \ 59 typeof(*(ptr)) __pu_val = (x); \ 60 switch (sizeof (*(ptr))) { \ 61 case 1: \ 62 __put_user_asm(__pu_err, __pu_val, ptr, b); \ 63 break; \ 64 case 2: \ 65 __put_user_asm(__pu_err, __pu_val, ptr, w); \ 66 break; \ 67 case 4: \ 68 __put_user_asm(__pu_err, __pu_val, ptr, l); \ 69 break; \ 70 case 8: \ 71 memcpy(ptr, &__pu_val, sizeof (*(ptr))); \ 72 break; \ 73 default: \ 74 __pu_err = __put_user_bad(); \ 75 break; \ 76 } \ 77 __pu_err; \ 78}) 79#define __put_user(x, ptr) put_user(x, ptr) 80 81extern int __put_user_bad(void); 82 83/* 84 * Tell gcc we read from memory instead of writing: this is because 85 * we do not write to any memory gcc knows about, so there are no 86 * aliasing issues. 87 */ 88 89#define __ptr(x) ((unsigned long *)(x)) 90 91#define __put_user_asm(err,x,ptr,bwl) \ 92 __asm__ ("move" #bwl " %0,%1" \ 93 : /* no outputs */ \ 94 :"d" (x),"m" (*__ptr(ptr)) : "memory") 95 96#define get_user(x, ptr) \ 97({ \ 98 int __gu_err = 0; \ 99 typeof(x) __gu_val = 0; \ 100 switch (sizeof(*(ptr))) { \ 101 case 1: \ 102 __get_user_asm(__gu_err, __gu_val, ptr, b, "=d"); \ 103 break; \ 104 case 2: \ 105 __get_user_asm(__gu_err, __gu_val, ptr, w, "=r"); \ 106 break; \ 107 case 4: \ 108 __get_user_asm(__gu_err, __gu_val, ptr, l, "=r"); \ 109 break; \ 110 case 8: \ 111 memcpy((void *) &__gu_val, ptr, sizeof (*(ptr))); \ 112 break; \ 113 default: \ 114 __gu_val = 0; \ 115 __gu_err = __get_user_bad(); \ 116 break; \ 117 } \ 118 (x) = (typeof(*(ptr))) __gu_val; \ 119 __gu_err; \ 120}) 121#define __get_user(x, ptr) get_user(x, ptr) 122 123extern int __get_user_bad(void); 124 125#define __get_user_asm(err,x,ptr,bwl,reg) \ 126 __asm__ ("move" #bwl " %1,%0" \ 127 : "=d" (x) \ 128 : "m" (*__ptr(ptr))) 129 130#define copy_from_user(to, from, n) (memcpy(to, from, n), 0) 131#define copy_to_user(to, from, n) (memcpy(to, from, n), 0) 132 133#define __copy_from_user(to, from, n) copy_from_user(to, from, n) 134#define __copy_to_user(to, from, n) copy_to_user(to, from, n) 135#define __copy_to_user_inatomic __copy_to_user 136#define __copy_from_user_inatomic __copy_from_user 137 138#define copy_to_user_ret(to,from,n,retval) ({ if (copy_to_user(to,from,n)) return retval; }) 139 140#define copy_from_user_ret(to,from,n,retval) ({ if (copy_from_user(to,from,n)) return retval; }) 141 142/* 143 * Copy a null terminated string from userspace. 144 */ 145 146static inline long 147strncpy_from_user(char *dst, const char *src, long count) 148{ 149 char *tmp; 150 strncpy(dst, src, count); 151 for (tmp = dst; *tmp && count > 0; tmp++, count--) 152 ; 153 return(tmp - dst); /* DAVIDM should we count a NUL ? check getname */ 154} 155 156/* 157 * Return the size of a string (including the ending 0) 158 * 159 * Return 0 on exception, a value greater than N if too long 160 */ 161static inline long strnlen_user(const char *src, long n) 162{ 163 return(strlen(src) + 1); /* DAVIDM make safer */ 164} 165 166#define strlen_user(str) strnlen_user(str, 32767) 167 168/* 169 * Zero Userspace 170 */ 171 172static inline unsigned long 173__clear_user(void *to, unsigned long n) 174{ 175 memset(to, 0, n); 176 return 0; 177} 178 179#define clear_user(to,n) __clear_user(to,n) 180 181#endif /* _M68KNOMMU_UACCESS_H */ 182