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- /* SPDX-License-Identifier: GPL-2.0 */
- #ifndef _ASM_X86_UACCESS_H
- #define _ASM_X86_UACCESS_H
- /*
- * User space memory access functions
- */
- #include <linux/compiler.h>
- #include <linux/instrumented.h>
- #include <linux/kasan-checks.h>
- #include <linux/string.h>
- #include <asm/asm.h>
- #include <asm/page.h>
- #include <asm/smap.h>
- #include <asm/extable.h>
- #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
- static inline bool pagefault_disabled(void);
- # define WARN_ON_IN_IRQ() \
- WARN_ON_ONCE(!in_task() && !pagefault_disabled())
- #else
- # define WARN_ON_IN_IRQ()
- #endif
- /**
- * access_ok - Checks if a user space pointer is valid
- * @addr: User space pointer to start of block to check
- * @size: Size of block to check
- *
- * Context: User context only. This function may sleep if pagefaults are
- * enabled.
- *
- * Checks if a pointer to a block of memory in user space is valid.
- *
- * Note that, depending on architecture, this function probably just
- * checks that the pointer is in the user space range - after calling
- * this function, memory access functions may still return -EFAULT.
- *
- * Return: true (nonzero) if the memory block may be valid, false (zero)
- * if it is definitely invalid.
- */
- #define access_ok(addr, size) \
- ({ \
- WARN_ON_IN_IRQ(); \
- likely(__access_ok(addr, size)); \
- })
- #include <asm-generic/access_ok.h>
- extern int __get_user_1(void);
- extern int __get_user_2(void);
- extern int __get_user_4(void);
- extern int __get_user_8(void);
- extern int __get_user_nocheck_1(void);
- extern int __get_user_nocheck_2(void);
- extern int __get_user_nocheck_4(void);
- extern int __get_user_nocheck_8(void);
- extern int __get_user_bad(void);
- #define __uaccess_begin() stac()
- #define __uaccess_end() clac()
- #define __uaccess_begin_nospec() \
- ({ \
- stac(); \
- barrier_nospec(); \
- })
- /*
- * This is the smallest unsigned integer type that can fit a value
- * (up to 'long long')
- */
- #define __inttype(x) __typeof__( \
- __typefits(x,char, \
- __typefits(x,short, \
- __typefits(x,int, \
- __typefits(x,long,0ULL)))))
- #define __typefits(x,type,not) \
- __builtin_choose_expr(sizeof(x)<=sizeof(type),(unsigned type)0,not)
- /*
- * This is used for both get_user() and __get_user() to expand to
- * the proper special function call that has odd calling conventions
- * due to returning both a value and an error, and that depends on
- * the size of the pointer passed in.
- *
- * Careful: we have to cast the result to the type of the pointer
- * for sign reasons.
- *
- * The use of _ASM_DX 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.
- *
- * Clang/LLVM cares about the size of the register, but still wants
- * the base register for something that ends up being a pair.
- */
- #define do_get_user_call(fn,x,ptr) \
- ({ \
- int __ret_gu; \
- register __inttype(*(ptr)) __val_gu asm("%"_ASM_DX); \
- __chk_user_ptr(ptr); \
- asm volatile("call __" #fn "_%P4" \
- : "=a" (__ret_gu), "=r" (__val_gu), \
- ASM_CALL_CONSTRAINT \
- : "0" (ptr), "i" (sizeof(*(ptr)))); \
- instrument_get_user(__val_gu); \
- (x) = (__force __typeof__(*(ptr))) __val_gu; \
- __builtin_expect(__ret_gu, 0); \
- })
- /**
- * 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 if pagefaults are
- * enabled.
- *
- * 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.
- *
- * Return: zero on success, or -EFAULT on error.
- * On error, the variable @x is set to zero.
- */
- #define get_user(x,ptr) ({ might_fault(); do_get_user_call(get_user,x,ptr); })
- /**
- * __get_user - Get a simple variable from user space, with less checking.
- * @x: Variable to store result.
- * @ptr: Source address, in user space.
- *
- * Context: User context only. This function may sleep if pagefaults are
- * enabled.
- *
- * 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.
- *
- * Caller must check the pointer with access_ok() before calling this
- * function.
- *
- * Return: zero on success, or -EFAULT on error.
- * On error, the variable @x is set to zero.
- */
- #define __get_user(x,ptr) do_get_user_call(get_user_nocheck,x,ptr)
- #ifdef CONFIG_X86_32
- #define __put_user_goto_u64(x, addr, label) \
- asm_volatile_goto("\n" \
- "1: movl %%eax,0(%1)\n" \
- "2: movl %%edx,4(%1)\n" \
- _ASM_EXTABLE_UA(1b, %l2) \
- _ASM_EXTABLE_UA(2b, %l2) \
- : : "A" (x), "r" (addr) \
- : : label)
- #else
- #define __put_user_goto_u64(x, ptr, label) \
- __put_user_goto(x, ptr, "q", "er", label)
- #endif
- extern void __put_user_bad(void);
- /*
- * Strange magic calling convention: pointer in %ecx,
- * value in %eax(:%edx), return value in %ecx. clobbers %rbx
- */
- extern void __put_user_1(void);
- extern void __put_user_2(void);
- extern void __put_user_4(void);
- extern void __put_user_8(void);
- extern void __put_user_nocheck_1(void);
- extern void __put_user_nocheck_2(void);
- extern void __put_user_nocheck_4(void);
- extern void __put_user_nocheck_8(void);
- /*
- * ptr must be evaluated and assigned to the temporary __ptr_pu before
- * the assignment of x to __val_pu, to avoid any function calls
- * involved in the ptr expression (possibly implicitly generated due
- * to KASAN) from clobbering %ax.
- */
- #define do_put_user_call(fn,x,ptr) \
- ({ \
- int __ret_pu; \
- void __user *__ptr_pu; \
- register __typeof__(*(ptr)) __val_pu asm("%"_ASM_AX); \
- __typeof__(*(ptr)) __x = (x); /* eval x once */ \
- __typeof__(ptr) __ptr = (ptr); /* eval ptr once */ \
- __chk_user_ptr(__ptr); \
- __ptr_pu = __ptr; \
- __val_pu = __x; \
- asm volatile("call __" #fn "_%P[size]" \
- : "=c" (__ret_pu), \
- ASM_CALL_CONSTRAINT \
- : "0" (__ptr_pu), \
- "r" (__val_pu), \
- [size] "i" (sizeof(*(ptr))) \
- :"ebx"); \
- instrument_put_user(__x, __ptr, sizeof(*(ptr))); \
- __builtin_expect(__ret_pu, 0); \
- })
- /**
- * put_user - Write a simple value into user space.
- * @x: Value to copy to user space.
- * @ptr: Destination address, in user space.
- *
- * Context: User context only. This function may sleep if pagefaults are
- * enabled.
- *
- * This macro copies a single simple value from kernel space to user
- * 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 @x must be assignable
- * to the result of dereferencing @ptr.
- *
- * Return: zero on success, or -EFAULT on error.
- */
- #define put_user(x, ptr) ({ might_fault(); do_put_user_call(put_user,x,ptr); })
- /**
- * __put_user - Write a simple value into user space, with less checking.
- * @x: Value to copy to user space.
- * @ptr: Destination address, in user space.
- *
- * Context: User context only. This function may sleep if pagefaults are
- * enabled.
- *
- * This macro copies a single simple value from kernel space to user
- * 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 @x must be assignable
- * to the result of dereferencing @ptr.
- *
- * Caller must check the pointer with access_ok() before calling this
- * function.
- *
- * Return: zero on success, or -EFAULT on error.
- */
- #define __put_user(x, ptr) do_put_user_call(put_user_nocheck,x,ptr)
- #define __put_user_size(x, ptr, size, label) \
- do { \
- __typeof__(*(ptr)) __x = (x); /* eval x once */ \
- __typeof__(ptr) __ptr = (ptr); /* eval ptr once */ \
- __chk_user_ptr(__ptr); \
- switch (size) { \
- case 1: \
- __put_user_goto(__x, __ptr, "b", "iq", label); \
- break; \
- case 2: \
- __put_user_goto(__x, __ptr, "w", "ir", label); \
- break; \
- case 4: \
- __put_user_goto(__x, __ptr, "l", "ir", label); \
- break; \
- case 8: \
- __put_user_goto_u64(__x, __ptr, label); \
- break; \
- default: \
- __put_user_bad(); \
- } \
- instrument_put_user(__x, __ptr, size); \
- } while (0)
- #ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT
- #ifdef CONFIG_X86_32
- #define __get_user_asm_u64(x, ptr, label) do { \
- unsigned int __gu_low, __gu_high; \
- const unsigned int __user *__gu_ptr; \
- __gu_ptr = (const void __user *)(ptr); \
- __get_user_asm(__gu_low, __gu_ptr, "l", "=r", label); \
- __get_user_asm(__gu_high, __gu_ptr+1, "l", "=r", label); \
- (x) = ((unsigned long long)__gu_high << 32) | __gu_low; \
- } while (0)
- #else
- #define __get_user_asm_u64(x, ptr, label) \
- __get_user_asm(x, ptr, "q", "=r", label)
- #endif
- #define __get_user_size(x, ptr, size, label) \
- do { \
- __chk_user_ptr(ptr); \
- switch (size) { \
- case 1: { \
- unsigned char x_u8__; \
- __get_user_asm(x_u8__, ptr, "b", "=q", label); \
- (x) = x_u8__; \
- break; \
- } \
- case 2: \
- __get_user_asm(x, ptr, "w", "=r", label); \
- break; \
- case 4: \
- __get_user_asm(x, ptr, "l", "=r", label); \
- break; \
- case 8: \
- __get_user_asm_u64(x, ptr, label); \
- break; \
- default: \
- (x) = __get_user_bad(); \
- } \
- instrument_get_user(x); \
- } while (0)
- #define __get_user_asm(x, addr, itype, ltype, label) \
- asm_volatile_goto("\n" \
- "1: mov"itype" %[umem],%[output]\n" \
- _ASM_EXTABLE_UA(1b, %l2) \
- : [output] ltype(x) \
- : [umem] "m" (__m(addr)) \
- : : label)
- #else // !CONFIG_CC_HAS_ASM_GOTO_OUTPUT
- #ifdef CONFIG_X86_32
- #define __get_user_asm_u64(x, ptr, retval) \
- ({ \
- __typeof__(ptr) __ptr = (ptr); \
- asm volatile("\n" \
- "1: movl %[lowbits],%%eax\n" \
- "2: movl %[highbits],%%edx\n" \
- "3:\n" \
- _ASM_EXTABLE_TYPE_REG(1b, 3b, EX_TYPE_EFAULT_REG | \
- EX_FLAG_CLEAR_AX_DX, \
- %[errout]) \
- _ASM_EXTABLE_TYPE_REG(2b, 3b, EX_TYPE_EFAULT_REG | \
- EX_FLAG_CLEAR_AX_DX, \
- %[errout]) \
- : [errout] "=r" (retval), \
- [output] "=&A"(x) \
- : [lowbits] "m" (__m(__ptr)), \
- [highbits] "m" __m(((u32 __user *)(__ptr)) + 1), \
- "0" (retval)); \
- })
- #else
- #define __get_user_asm_u64(x, ptr, retval) \
- __get_user_asm(x, ptr, retval, "q")
- #endif
- #define __get_user_size(x, ptr, size, retval) \
- do { \
- unsigned char x_u8__; \
- \
- retval = 0; \
- __chk_user_ptr(ptr); \
- switch (size) { \
- case 1: \
- __get_user_asm(x_u8__, ptr, retval, "b"); \
- (x) = x_u8__; \
- break; \
- case 2: \
- __get_user_asm(x, ptr, retval, "w"); \
- break; \
- case 4: \
- __get_user_asm(x, ptr, retval, "l"); \
- break; \
- case 8: \
- __get_user_asm_u64(x, ptr, retval); \
- break; \
- default: \
- (x) = __get_user_bad(); \
- } \
- } while (0)
- #define __get_user_asm(x, addr, err, itype) \
- asm volatile("\n" \
- "1: mov"itype" %[umem],%[output]\n" \
- "2:\n" \
- _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_EFAULT_REG | \
- EX_FLAG_CLEAR_AX, \
- %[errout]) \
- : [errout] "=r" (err), \
- [output] "=a" (x) \
- : [umem] "m" (__m(addr)), \
- "0" (err))
- #endif // CONFIG_CC_HAS_ASM_GOTO_OUTPUT
- #ifdef CONFIG_CC_HAS_ASM_GOTO_TIED_OUTPUT
- #define __try_cmpxchg_user_asm(itype, ltype, _ptr, _pold, _new, label) ({ \
- bool success; \
- __typeof__(_ptr) _old = (__typeof__(_ptr))(_pold); \
- __typeof__(*(_ptr)) __old = *_old; \
- __typeof__(*(_ptr)) __new = (_new); \
- asm_volatile_goto("\n" \
- "1: " LOCK_PREFIX "cmpxchg"itype" %[new], %[ptr]\n"\
- _ASM_EXTABLE_UA(1b, %l[label]) \
- : CC_OUT(z) (success), \
- [ptr] "+m" (*_ptr), \
- [old] "+a" (__old) \
- : [new] ltype (__new) \
- : "memory" \
- : label); \
- if (unlikely(!success)) \
- *_old = __old; \
- likely(success); })
- #ifdef CONFIG_X86_32
- #define __try_cmpxchg64_user_asm(_ptr, _pold, _new, label) ({ \
- bool success; \
- __typeof__(_ptr) _old = (__typeof__(_ptr))(_pold); \
- __typeof__(*(_ptr)) __old = *_old; \
- __typeof__(*(_ptr)) __new = (_new); \
- asm_volatile_goto("\n" \
- "1: " LOCK_PREFIX "cmpxchg8b %[ptr]\n" \
- _ASM_EXTABLE_UA(1b, %l[label]) \
- : CC_OUT(z) (success), \
- "+A" (__old), \
- [ptr] "+m" (*_ptr) \
- : "b" ((u32)__new), \
- "c" ((u32)((u64)__new >> 32)) \
- : "memory" \
- : label); \
- if (unlikely(!success)) \
- *_old = __old; \
- likely(success); })
- #endif // CONFIG_X86_32
- #else // !CONFIG_CC_HAS_ASM_GOTO_TIED_OUTPUT
- #define __try_cmpxchg_user_asm(itype, ltype, _ptr, _pold, _new, label) ({ \
- int __err = 0; \
- bool success; \
- __typeof__(_ptr) _old = (__typeof__(_ptr))(_pold); \
- __typeof__(*(_ptr)) __old = *_old; \
- __typeof__(*(_ptr)) __new = (_new); \
- asm volatile("\n" \
- "1: " LOCK_PREFIX "cmpxchg"itype" %[new], %[ptr]\n"\
- CC_SET(z) \
- "2:\n" \
- _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_EFAULT_REG, \
- %[errout]) \
- : CC_OUT(z) (success), \
- [errout] "+r" (__err), \
- [ptr] "+m" (*_ptr), \
- [old] "+a" (__old) \
- : [new] ltype (__new) \
- : "memory"); \
- if (unlikely(__err)) \
- goto label; \
- if (unlikely(!success)) \
- *_old = __old; \
- likely(success); })
- #ifdef CONFIG_X86_32
- /*
- * Unlike the normal CMPXCHG, use output GPR for both success/fail and error.
- * There are only six GPRs available and four (EAX, EBX, ECX, and EDX) are
- * hardcoded by CMPXCHG8B, leaving only ESI and EDI. If the compiler uses
- * both ESI and EDI for the memory operand, compilation will fail if the error
- * is an input+output as there will be no register available for input.
- */
- #define __try_cmpxchg64_user_asm(_ptr, _pold, _new, label) ({ \
- int __result; \
- __typeof__(_ptr) _old = (__typeof__(_ptr))(_pold); \
- __typeof__(*(_ptr)) __old = *_old; \
- __typeof__(*(_ptr)) __new = (_new); \
- asm volatile("\n" \
- "1: " LOCK_PREFIX "cmpxchg8b %[ptr]\n" \
- "mov $0, %[result]\n\t" \
- "setz %b[result]\n" \
- "2:\n" \
- _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_EFAULT_REG, \
- %[result]) \
- : [result] "=q" (__result), \
- "+A" (__old), \
- [ptr] "+m" (*_ptr) \
- : "b" ((u32)__new), \
- "c" ((u32)((u64)__new >> 32)) \
- : "memory", "cc"); \
- if (unlikely(__result < 0)) \
- goto label; \
- if (unlikely(!__result)) \
- *_old = __old; \
- likely(__result); })
- #endif // CONFIG_X86_32
- #endif // CONFIG_CC_HAS_ASM_GOTO_TIED_OUTPUT
- /* FIXME: this hack is definitely wrong -AK */
- struct __large_struct { unsigned long buf[100]; };
- #define __m(x) (*(struct __large_struct __user *)(x))
- /*
- * 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 __put_user_goto(x, addr, itype, ltype, label) \
- asm_volatile_goto("\n" \
- "1: mov"itype" %0,%1\n" \
- _ASM_EXTABLE_UA(1b, %l2) \
- : : ltype(x), "m" (__m(addr)) \
- : : label)
- extern unsigned long
- copy_from_user_nmi(void *to, const void __user *from, unsigned long n);
- extern __must_check long
- strncpy_from_user(char *dst, const char __user *src, long count);
- extern __must_check long strnlen_user(const char __user *str, long n);
- #ifdef CONFIG_ARCH_HAS_COPY_MC
- unsigned long __must_check
- copy_mc_to_kernel(void *to, const void *from, unsigned len);
- #define copy_mc_to_kernel copy_mc_to_kernel
- unsigned long __must_check
- copy_mc_to_user(void __user *to, const void *from, unsigned len);
- #endif
- /*
- * movsl can be slow when source and dest are not both 8-byte aligned
- */
- #ifdef CONFIG_X86_INTEL_USERCOPY
- extern struct movsl_mask {
- int mask;
- } ____cacheline_aligned_in_smp movsl_mask;
- #endif
- #define ARCH_HAS_NOCACHE_UACCESS 1
- #ifdef CONFIG_X86_32
- unsigned long __must_check clear_user(void __user *mem, unsigned long len);
- unsigned long __must_check __clear_user(void __user *mem, unsigned long len);
- # include <asm/uaccess_32.h>
- #else
- # include <asm/uaccess_64.h>
- #endif
- /*
- * The "unsafe" user accesses aren't really "unsafe", but the naming
- * is a big fat warning: you have to not only do the access_ok()
- * checking before using them, but you have to surround them with the
- * user_access_begin/end() pair.
- */
- static __must_check __always_inline bool user_access_begin(const void __user *ptr, size_t len)
- {
- if (unlikely(!access_ok(ptr,len)))
- return 0;
- __uaccess_begin_nospec();
- return 1;
- }
- #define user_access_begin(a,b) user_access_begin(a,b)
- #define user_access_end() __uaccess_end()
- #define user_access_save() smap_save()
- #define user_access_restore(x) smap_restore(x)
- #define unsafe_put_user(x, ptr, label) \
- __put_user_size((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)), label)
- #ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT
- #define unsafe_get_user(x, ptr, err_label) \
- do { \
- __inttype(*(ptr)) __gu_val; \
- __get_user_size(__gu_val, (ptr), sizeof(*(ptr)), err_label); \
- (x) = (__force __typeof__(*(ptr)))__gu_val; \
- } while (0)
- #else // !CONFIG_CC_HAS_ASM_GOTO_OUTPUT
- #define unsafe_get_user(x, ptr, err_label) \
- do { \
- int __gu_err; \
- __inttype(*(ptr)) __gu_val; \
- __get_user_size(__gu_val, (ptr), sizeof(*(ptr)), __gu_err); \
- (x) = (__force __typeof__(*(ptr)))__gu_val; \
- if (unlikely(__gu_err)) goto err_label; \
- } while (0)
- #endif // CONFIG_CC_HAS_ASM_GOTO_OUTPUT
- extern void __try_cmpxchg_user_wrong_size(void);
- #ifndef CONFIG_X86_32
- #define __try_cmpxchg64_user_asm(_ptr, _oldp, _nval, _label) \
- __try_cmpxchg_user_asm("q", "r", (_ptr), (_oldp), (_nval), _label)
- #endif
- /*
- * Force the pointer to u<size> to match the size expected by the asm helper.
- * clang/LLVM compiles all cases and only discards the unused paths after
- * processing errors, which breaks i386 if the pointer is an 8-byte value.
- */
- #define unsafe_try_cmpxchg_user(_ptr, _oldp, _nval, _label) ({ \
- bool __ret; \
- __chk_user_ptr(_ptr); \
- switch (sizeof(*(_ptr))) { \
- case 1: __ret = __try_cmpxchg_user_asm("b", "q", \
- (__force u8 *)(_ptr), (_oldp), \
- (_nval), _label); \
- break; \
- case 2: __ret = __try_cmpxchg_user_asm("w", "r", \
- (__force u16 *)(_ptr), (_oldp), \
- (_nval), _label); \
- break; \
- case 4: __ret = __try_cmpxchg_user_asm("l", "r", \
- (__force u32 *)(_ptr), (_oldp), \
- (_nval), _label); \
- break; \
- case 8: __ret = __try_cmpxchg64_user_asm((__force u64 *)(_ptr), (_oldp),\
- (_nval), _label); \
- break; \
- default: __try_cmpxchg_user_wrong_size(); \
- } \
- __ret; })
- /* "Returns" 0 on success, 1 on failure, -EFAULT if the access faults. */
- #define __try_cmpxchg_user(_ptr, _oldp, _nval, _label) ({ \
- int __ret = -EFAULT; \
- __uaccess_begin_nospec(); \
- __ret = !unsafe_try_cmpxchg_user(_ptr, _oldp, _nval, _label); \
- _label: \
- __uaccess_end(); \
- __ret; \
- })
- /*
- * We want the unsafe accessors to always be inlined and use
- * the error labels - thus the macro games.
- */
- #define unsafe_copy_loop(dst, src, len, type, label) \
- while (len >= sizeof(type)) { \
- unsafe_put_user(*(type *)(src),(type __user *)(dst),label); \
- dst += sizeof(type); \
- src += sizeof(type); \
- len -= sizeof(type); \
- }
- #define unsafe_copy_to_user(_dst,_src,_len,label) \
- do { \
- char __user *__ucu_dst = (_dst); \
- const char *__ucu_src = (_src); \
- size_t __ucu_len = (_len); \
- unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u64, label); \
- unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u32, label); \
- unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u16, label); \
- unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u8, label); \
- } while (0)
- #ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT
- #define __get_kernel_nofault(dst, src, type, err_label) \
- __get_user_size(*((type *)(dst)), (__force type __user *)(src), \
- sizeof(type), err_label)
- #else // !CONFIG_CC_HAS_ASM_GOTO_OUTPUT
- #define __get_kernel_nofault(dst, src, type, err_label) \
- do { \
- int __kr_err; \
- \
- __get_user_size(*((type *)(dst)), (__force type __user *)(src), \
- sizeof(type), __kr_err); \
- if (unlikely(__kr_err)) \
- goto err_label; \
- } while (0)
- #endif // CONFIG_CC_HAS_ASM_GOTO_OUTPUT
- #define __put_kernel_nofault(dst, src, type, err_label) \
- __put_user_size(*((type *)(src)), (__force type __user *)(dst), \
- sizeof(type), err_label)
- #endif /* _ASM_X86_UACCESS_H */
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