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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/x86/include/asm/uaccess.h
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/include/asm/uaccess.h')
-rw-r--r--arch/x86/include/asm/uaccess.h672
1 files changed, 672 insertions, 0 deletions
diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
new file mode 100644
index 000000000..6ca0c661c
--- /dev/null
+++ b/arch/x86/include/asm/uaccess.h
@@ -0,0 +1,672 @@
+/* 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 */
+