Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
Greg Ungerer | 1014680 | 2007-07-19 01:49:15 -0700 | [diff] [blame] | 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 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | static inline int _access_ok(unsigned long addr, unsigned long size) |
| 25 | { |
Greg Ungerer | 1014680 | 2007-07-19 01:49:15 -0700 | [diff] [blame] | 26 | return 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | } |
| 28 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
| 42 | struct exception_table_entry |
| 43 | { |
| 44 | unsigned long insn, fixup; |
| 45 | }; |
| 46 | |
| 47 | /* Returns 0 if exception not found and fixup otherwise. */ |
| 48 | extern 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 | |
| 81 | extern 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; \ |
Greg Ungerer | 1b0f06d | 2006-07-13 09:32:41 +1000 | [diff] [blame] | 99 | typeof(x) __gu_val = 0; \ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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: \ |
Greg Ungerer | 1b0f06d | 2006-07-13 09:32:41 +1000 | [diff] [blame] | 111 | memcpy((void *) &__gu_val, ptr, sizeof (*(ptr))); \ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | break; \ |
| 113 | default: \ |
| 114 | __gu_val = 0; \ |
| 115 | __gu_err = __get_user_bad(); \ |
| 116 | break; \ |
| 117 | } \ |
Greg Ungerer | 1b0f06d | 2006-07-13 09:32:41 +1000 | [diff] [blame] | 118 | (x) = (typeof(*(ptr))) __gu_val; \ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | __gu_err; \ |
| 120 | }) |
| 121 | #define __get_user(x, ptr) get_user(x, ptr) |
| 122 | |
| 123 | extern int __get_user_bad(void); |
| 124 | |
Greg Ungerer | 1b0f06d | 2006-07-13 09:32:41 +1000 | [diff] [blame] | 125 | #define __get_user_asm(err,x,ptr,bwl,reg) \ |
| 126 | __asm__ ("move" #bwl " %1,%0" \ |
| 127 | : "=d" (x) \ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
| 146 | static inline long |
| 147 | strncpy_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 | */ |
| 161 | static 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 | |
| 172 | static inline unsigned long |
Matt Waddel | fa2eae9 | 2007-10-23 14:37:54 +1000 | [diff] [blame] | 173 | __clear_user(void *to, unsigned long n) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 174 | { |
| 175 | memset(to, 0, n); |
| 176 | return 0; |
| 177 | } |
| 178 | |
Matt Waddel | fa2eae9 | 2007-10-23 14:37:54 +1000 | [diff] [blame] | 179 | #define clear_user(to,n) __clear_user(to,n) |
| 180 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 181 | #endif /* _M68KNOMMU_UACCESS_H */ |