diff options
Diffstat (limited to 'arch/x86/include/asm/uaccess.h')
| -rw-r--r-- | arch/x86/include/asm/uaccess.h | 97 |
1 files changed, 21 insertions, 76 deletions
diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index 7ccf8d131535..5ee26875baea 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -125,13 +125,12 @@ extern int __get_user_4(void); extern int __get_user_8(void); extern int __get_user_bad(void); -#define __get_user_x(size, ret, x, ptr) \ - asm volatile("call __get_user_" #size \ - : "=a" (ret), "=d" (x) \ - : "0" (ptr)) \ - -/* Careful: we have to cast the result to the type of the pointer - * for sign reasons */ +/* + * This is a type: either unsigned long, if the argument fits into + * that type, or otherwise unsigned long long. + */ +#define __inttype(x) \ +__typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL)) /** * get_user: - Get a simple variable from user space. @@ -150,38 +149,26 @@ extern int __get_user_bad(void); * Returns zero on success, or -EFAULT on error. * On error, the variable @x is set to zero. */ -#ifdef CONFIG_X86_32 -#define __get_user_8(__ret_gu, __val_gu, ptr) \ - __get_user_x(X, __ret_gu, __val_gu, ptr) -#else -#define __get_user_8(__ret_gu, __val_gu, ptr) \ - __get_user_x(8, __ret_gu, __val_gu, ptr) -#endif - +/* + * Careful: we have to cast the result to the type of the pointer + * for sign reasons. + * + * The use of %edx as the register specifier is a bit of a + * simplification, as gcc only cares about it as the starting point + * and not size: for a 64-bit value it will use %ecx:%edx on 32 bits + * (%ecx being the next register in gcc's x86 register sequence), and + * %rdx on 64 bits. + */ #define get_user(x, ptr) \ ({ \ int __ret_gu; \ - unsigned long __val_gu; \ + register __inttype(*(ptr)) __val_gu asm("%edx"); \ __chk_user_ptr(ptr); \ might_fault(); \ - switch (sizeof(*(ptr))) { \ - case 1: \ - __get_user_x(1, __ret_gu, __val_gu, ptr); \ - break; \ - case 2: \ - __get_user_x(2, __ret_gu, __val_gu, ptr); \ - break; \ - case 4: \ - __get_user_x(4, __ret_gu, __val_gu, ptr); \ - break; \ - case 8: \ - __get_user_8(__ret_gu, __val_gu, ptr); \ - break; \ - default: \ - __get_user_x(X, __ret_gu, __val_gu, ptr); \ - break; \ - } \ - (x) = (__typeof__(*(ptr)))__val_gu; \ + asm volatile("call __get_user_%P3" \ + : "=a" (__ret_gu), "=r" (__val_gu) \ + : "0" (ptr), "i" (sizeof(*(ptr)))); \ + (x) = (__typeof__(*(ptr))) __val_gu; \ __ret_gu; \ }) @@ -237,8 +224,6 @@ extern void __put_user_2(void); extern void __put_user_4(void); extern void __put_user_8(void); -#ifdef CONFIG_X86_WP_WORKS_OK - /** * put_user: - Write a simple value into user space. * @x: Value to copy to user space. @@ -326,29 +311,6 @@ do { \ } \ } while (0) -#else - -#define __put_user_size(x, ptr, size, retval, errret) \ -do { \ - __typeof__(*(ptr))__pus_tmp = x; \ - retval = 0; \ - \ - if (unlikely(__copy_to_user_ll(ptr, &__pus_tmp, size) != 0)) \ - retval = errret; \ -} while (0) - -#define put_user(x, ptr) \ -({ \ - int __ret_pu; \ - __typeof__(*(ptr))__pus_tmp = x; \ - __ret_pu = 0; \ - if (unlikely(__copy_to_user_ll(ptr, &__pus_tmp, \ - sizeof(*(ptr))) != 0)) \ - __ret_pu = -EFAULT; \ - __ret_pu; \ -}) -#endif - #ifdef CONFIG_X86_32 #define __get_user_asm_u64(x, ptr, retval, errret) (x) = __get_user_bad() #define __get_user_asm_ex_u64(x, ptr) (x) = __get_user_bad() @@ -543,29 +505,12 @@ struct __large_struct { unsigned long buf[100]; }; (x) = (__force __typeof__(*(ptr)))__gue_val; \ } while (0) -#ifdef CONFIG_X86_WP_WORKS_OK - #define put_user_try uaccess_try #define put_user_catch(err) uaccess_catch(err) #define put_user_ex(x, ptr) \ __put_user_size_ex((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr))) -#else /* !CONFIG_X86_WP_WORKS_OK */ - -#define put_user_try do { \ - int __uaccess_err = 0; - -#define put_user_catch(err) \ - (err) |= __uaccess_err; \ -} while (0) - -#define put_user_ex(x, ptr) do { \ - __uaccess_err |= __put_user(x, ptr); \ -} while (0) - -#endif /* CONFIG_X86_WP_WORKS_OK */ - extern unsigned long copy_from_user_nmi(void *to, const void __user *from, unsigned long n); extern __must_check long |