| /* 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/mm_types.h> | |
| #include <linux/string.h> | |
| #include <linux/mmap_lock.h> | |
| #include <asm/asm.h> | |
| #include <asm/page.h> | |
| #include <asm/smap.h> | |
| #include <asm/extable.h> | |
| #include <asm/tlbflush.h> | |
| #ifdef CONFIG_X86_32 | |
| # include <asm/uaccess_32.h> | |
| #else | |
| # include <asm/uaccess_64.h> | |
| #endif | |
| #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 "_%c[size]" \ | |
| : "=a" (__ret_gu), "=r" (__val_gu), \ | |
| ASM_CALL_CONSTRAINT \ | |
| : "0" (ptr), [size] "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 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 "_%c[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_goto_output("\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_goto_output("\n" \ | |
| "1: " LOCK_PREFIX "cmpxchg"itype" %[new], %[ptr]\n"\ | |
| _ASM_EXTABLE_UA(1b, %l[label]) \ | |
| : "=@ccz" (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_goto_output("\n" \ | |
| "1: " LOCK_PREFIX "cmpxchg8b %[ptr]\n" \ | |
| _ASM_EXTABLE_UA(1b, %l[label]) \ | |
| : "=@ccz" (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"\ | |
| "2:\n" \ | |
| _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_EFAULT_REG, \ | |
| %[errout]) \ | |
| : "=@ccz" (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 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_NONTEMPORAL_UACCESS 1 | |
| /* | |
| * 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 arch_unsafe_put_user(x, ptr, label) \ | |
| __put_user_size((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)), label) | |
| #ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT | |
| #define arch_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 arch_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 arch_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 arch_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 arch_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 */ | |