diff options
Diffstat (limited to 'arch/m68knommu/include/asm/uaccess.h')
| -rw-r--r-- | arch/m68knommu/include/asm/uaccess.h | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/arch/m68knommu/include/asm/uaccess.h b/arch/m68knommu/include/asm/uaccess.h new file mode 100644 index 00000000000..68bbe9b312f --- /dev/null +++ b/arch/m68knommu/include/asm/uaccess.h @@ -0,0 +1,181 @@ +#ifndef __M68KNOMMU_UACCESS_H +#define __M68KNOMMU_UACCESS_H + +/* + * User space memory access functions + */ +#include <linux/sched.h> +#include <linux/mm.h> +#include <linux/string.h> + +#include <asm/segment.h> + +#define VERIFY_READ 0 +#define VERIFY_WRITE 1 + +#define access_ok(type,addr,size) _access_ok((unsigned long)(addr),(size)) + +/* + * It is not enough to just have access_ok check for a real RAM address. + * This would disallow the case of code/ro-data running XIP in flash/rom. + * Ideally we would check the possible flash ranges too, but that is + * currently not so easy. + */ +static inline int _access_ok(unsigned long addr, unsigned long size) +{ + return 1; +} + +/* + * The exception table consists of pairs of addresses: the first is the + * address of an instruction that is allowed to fault, and the second is + * the address at which the program should continue. No registers are + * modified, so it is entirely up to the continuation code to figure out + * what to do. + * + * All the routines below use bits of fixup code that are out of line + * with the main instruction path. This means when everything is well, + * we don't even have to jump over them. Further, they do not intrude + * on our cache or tlb entries. + */ + +struct exception_table_entry +{ + unsigned long insn, fixup; +}; + +/* Returns 0 if exception not found and fixup otherwise. */ +extern unsigned long search_exception_table(unsigned long); + + +/* + * These are the main single-value transfer routines. They automatically + * use the right size if we just have the right pointer type. + */ + +#define put_user(x, ptr) \ +({ \ + int __pu_err = 0; \ + typeof(*(ptr)) __pu_val = (x); \ + switch (sizeof (*(ptr))) { \ + case 1: \ + __put_user_asm(__pu_err, __pu_val, ptr, b); \ + break; \ + case 2: \ + __put_user_asm(__pu_err, __pu_val, ptr, w); \ + break; \ + case 4: \ + __put_user_asm(__pu_err, __pu_val, ptr, l); \ + break; \ + case 8: \ + memcpy(ptr, &__pu_val, sizeof (*(ptr))); \ + break; \ + default: \ + __pu_err = __put_user_bad(); \ + break; \ + } \ + __pu_err; \ +}) +#define __put_user(x, ptr) put_user(x, ptr) + +extern int __put_user_bad(void); + +/* + * Tell gcc we read from memory instead of writing: this is because + * we do not write to any memory gcc knows about, so there are no + * aliasing issues. + */ + +#define __ptr(x) ((unsigned long *)(x)) + +#define __put_user_asm(err,x,ptr,bwl) \ + __asm__ ("move" #bwl " %0,%1" \ + : /* no outputs */ \ + :"d" (x),"m" (*__ptr(ptr)) : "memory") + +#define get_user(x, ptr) \ +({ \ + int __gu_err = 0; \ + typeof(x) __gu_val = 0; \ + switch (sizeof(*(ptr))) { \ + case 1: \ + __get_user_asm(__gu_err, __gu_val, ptr, b, "=d"); \ + break; \ + case 2: \ + __get_user_asm(__gu_err, __gu_val, ptr, w, "=r"); \ + break; \ + case 4: \ + __get_user_asm(__gu_err, __gu_val, ptr, l, "=r"); \ + break; \ + case 8: \ + memcpy((void *) &__gu_val, ptr, sizeof (*(ptr))); \ + break; \ + default: \ + __gu_val = 0; \ + __gu_err = __get_user_bad(); \ + break; \ + } \ + (x) = (typeof(*(ptr))) __gu_val; \ + __gu_err; \ +}) +#define __get_user(x, ptr) get_user(x, ptr) + +extern int __get_user_bad(void); + +#define __get_user_asm(err,x,ptr,bwl,reg) \ + __asm__ ("move" #bwl " %1,%0" \ + : "=d" (x) \ + : "m" (*__ptr(ptr))) + +#define copy_from_user(to, from, n) (memcpy(to, from, n), 0) +#define copy_to_user(to, from, n) (memcpy(to, from, n), 0) + +#define __copy_from_user(to, from, n) copy_from_user(to, from, n) +#define __copy_to_user(to, from, n) copy_to_user(to, from, n) +#define __copy_to_user_inatomic __copy_to_user +#define __copy_from_user_inatomic __copy_from_user + +#define copy_to_user_ret(to,from,n,retval) ({ if (copy_to_user(to,from,n)) return retval; }) + +#define copy_from_user_ret(to,from,n,retval) ({ if (copy_from_user(to,from,n)) return retval; }) + +/* + * Copy a null terminated string from userspace. + */ + +static inline long +strncpy_from_user(char *dst, const char *src, long count) +{ + char *tmp; + strncpy(dst, src, count); + for (tmp = dst; *tmp && count > 0; tmp++, count--) + ; + return(tmp - dst); /* DAVIDM should we count a NUL ? check getname */ +} + +/* + * Return the size of a string (including the ending 0) + * + * Return 0 on exception, a value greater than N if too long + */ +static inline long strnlen_user(const char *src, long n) +{ + return(strlen(src) + 1); /* DAVIDM make safer */ +} + +#define strlen_user(str) strnlen_user(str, 32767) + +/* + * Zero Userspace + */ + +static inline unsigned long +__clear_user(void *to, unsigned long n) +{ + memset(to, 0, n); + return 0; +} + +#define clear_user(to,n) __clear_user(to,n) + +#endif /* _M68KNOMMU_UACCESS_H */ |