diff options
| -rw-r--r-- | arch/microblaze/include/asm/uaccess.h | 89 |
1 files changed, 66 insertions, 23 deletions
diff --git a/arch/microblaze/include/asm/uaccess.h b/arch/microblaze/include/asm/uaccess.h index 1af92025fff..b079ac31a67 100644 --- a/arch/microblaze/include/asm/uaccess.h +++ b/arch/microblaze/include/asm/uaccess.h @@ -146,31 +146,75 @@ static inline unsigned long __must_check clear_user(void __user *to, #ifndef CONFIG_MMU -/* Undefined function to trigger linker error */ -extern int bad_user_access_length(void); +extern long __user_bad(void); + +#define __get_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \ +({ \ + __asm__ __volatile__ ( \ + "1:" insn " %1, %2, r0;" \ + " addk %0, r0, r0;" \ + "2: " \ + __FIXUP_SECTION \ + "3: brid 2b;" \ + " addik %0, r0, %3;" \ + ".previous;" \ + __EX_TABLE_SECTION \ + ".word 1b,3b;" \ + ".previous;" \ + : "=&r"(__gu_err), "=r"(__gu_val) \ + : "r"(__gu_ptr), "i"(-EFAULT) \ + ); \ +}) + +/** + * get_user: - Get a simple variable from user space. + * @x: Variable to store result. + * @ptr: Source address, in user space. + * + * Context: User context only. This function may sleep. + * + * This macro copies a single simple variable from user space to kernel + * space. It supports simple types like char and int, but not larger + * data types like structures or arrays. + * + * @ptr must have pointer-to-simple-variable type, and the result of + * dereferencing @ptr must be assignable to @x without a cast. + * + * Returns zero on success, or -EFAULT on error. + * On error, the variable @x is set to zero. + */ + +#define __get_user(x, ptr) \ +({ \ + unsigned long __gu_val; \ + /*unsigned long __gu_ptr = (unsigned long)(ptr);*/ \ + long __gu_err; \ + switch (sizeof(*(ptr))) { \ + case 1: \ + __get_user_asm("lbu", (ptr), __gu_val, __gu_err); \ + break; \ + case 2: \ + __get_user_asm("lhu", (ptr), __gu_val, __gu_err); \ + break; \ + case 4: \ + __get_user_asm("lw", (ptr), __gu_val, __gu_err); \ + break; \ + default: \ + /* __gu_val = 0; __gu_err = -EINVAL;*/ __gu_err = __user_bad();\ + } \ + x = (__typeof__(*(ptr))) __gu_val; \ + __gu_err; \ +}) + -/* FIXME this is function for optimalization -> memcpy */ -#define __get_user(var, ptr) \ -({ \ - int __gu_err = 0; \ - switch (sizeof(*(ptr))) { \ - case 1: \ - case 2: \ - case 4: \ - (var) = *(ptr); \ - break; \ - case 8: \ - memcpy((void *) &(var), (ptr), 8); \ - break; \ - default: \ - (var) = 0; \ - __gu_err = __get_user_bad(); \ - break; \ - } \ - __gu_err; \ +#define get_user(x, ptr) \ +({ \ + access_ok(VERIFY_READ, (ptr), sizeof(*(ptr))) \ + ? __get_user((x), (ptr)) : -EFAULT; \ }) -#define __get_user_bad() (bad_user_access_length(), (-EFAULT)) +/* Undefined function to trigger linker error */ +extern int bad_user_access_length(void); /* FIXME is not there defined __pu_val */ #define __put_user(var, ptr) \ @@ -197,7 +241,6 @@ extern int bad_user_access_length(void); #define __put_user_bad() (bad_user_access_length(), (-EFAULT)) #define put_user(x, ptr) __put_user((x), (ptr)) -#define get_user(x, ptr) __get_user((x), (ptr)) #define copy_to_user(to, from, n) (memcpy((to), (from), (n)), 0) #define copy_from_user(to, from, n) (memcpy((to), (from), (n)), 0) |