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Diffstat (limited to 'arch/x86/include/asm/uaccess_64.h')
-rw-r--r--arch/x86/include/asm/uaccess_64.h236
1 files changed, 236 insertions, 0 deletions
diff --git a/arch/x86/include/asm/uaccess_64.h b/arch/x86/include/asm/uaccess_64.h
new file mode 100644
index 000000000..f2f9b39b2
--- /dev/null
+++ b/arch/x86/include/asm/uaccess_64.h
@@ -0,0 +1,236 @@
+#ifndef _ASM_X86_UACCESS_64_H
+#define _ASM_X86_UACCESS_64_H
+
+/*
+ * User space memory access functions
+ */
+#include <linux/compiler.h>
+#include <linux/errno.h>
+#include <linux/lockdep.h>
+#include <asm/alternative.h>
+#include <asm/cpufeature.h>
+#include <asm/page.h>
+
+/*
+ * Copy To/From Userspace
+ */
+
+/* Handles exceptions in both to and from, but doesn't do access_ok */
+__must_check unsigned long
+copy_user_enhanced_fast_string(void *to, const void *from, unsigned len);
+__must_check unsigned long
+copy_user_generic_string(void *to, const void *from, unsigned len);
+__must_check unsigned long
+copy_user_generic_unrolled(void *to, const void *from, unsigned len);
+
+static __always_inline __must_check unsigned long
+copy_user_generic(void *to, const void *from, unsigned len)
+{
+ unsigned ret;
+
+ /*
+ * If CPU has ERMS feature, use copy_user_enhanced_fast_string.
+ * Otherwise, if CPU has rep_good feature, use copy_user_generic_string.
+ * Otherwise, use copy_user_generic_unrolled.
+ */
+ alternative_call_2(copy_user_generic_unrolled,
+ copy_user_generic_string,
+ X86_FEATURE_REP_GOOD,
+ copy_user_enhanced_fast_string,
+ X86_FEATURE_ERMS,
+ ASM_OUTPUT2("=a" (ret), "=D" (to), "=S" (from),
+ "=d" (len)),
+ "1" (to), "2" (from), "3" (len)
+ : "memory", "rcx", "r8", "r9", "r10", "r11");
+ return ret;
+}
+
+__must_check unsigned long
+copy_in_user(void __user *to, const void __user *from, unsigned len);
+
+static __always_inline __must_check
+int __copy_from_user_nocheck(void *dst, const void __user *src, unsigned size)
+{
+ int ret = 0;
+
+ if (!__builtin_constant_p(size))
+ return copy_user_generic(dst, (__force void *)src, size);
+ switch (size) {
+ case 1:__get_user_asm(*(u8 *)dst, (u8 __user *)src,
+ ret, "b", "b", "=q", 1);
+ return ret;
+ case 2:__get_user_asm(*(u16 *)dst, (u16 __user *)src,
+ ret, "w", "w", "=r", 2);
+ return ret;
+ case 4:__get_user_asm(*(u32 *)dst, (u32 __user *)src,
+ ret, "l", "k", "=r", 4);
+ return ret;
+ case 8:__get_user_asm(*(u64 *)dst, (u64 __user *)src,
+ ret, "q", "", "=r", 8);
+ return ret;
+ case 10:
+ __get_user_asm(*(u64 *)dst, (u64 __user *)src,
+ ret, "q", "", "=r", 10);
+ if (unlikely(ret))
+ return ret;
+ __get_user_asm(*(u16 *)(8 + (char *)dst),
+ (u16 __user *)(8 + (char __user *)src),
+ ret, "w", "w", "=r", 2);
+ return ret;
+ case 16:
+ __get_user_asm(*(u64 *)dst, (u64 __user *)src,
+ ret, "q", "", "=r", 16);
+ if (unlikely(ret))
+ return ret;
+ __get_user_asm(*(u64 *)(8 + (char *)dst),
+ (u64 __user *)(8 + (char __user *)src),
+ ret, "q", "", "=r", 8);
+ return ret;
+ default:
+ return copy_user_generic(dst, (__force void *)src, size);
+ }
+}
+
+static __always_inline __must_check
+int __copy_from_user(void *dst, const void __user *src, unsigned size)
+{
+ might_fault();
+ return __copy_from_user_nocheck(dst, src, size);
+}
+
+static __always_inline __must_check
+int __copy_to_user_nocheck(void __user *dst, const void *src, unsigned size)
+{
+ int ret = 0;
+
+ if (!__builtin_constant_p(size))
+ return copy_user_generic((__force void *)dst, src, size);
+ switch (size) {
+ case 1:__put_user_asm(*(u8 *)src, (u8 __user *)dst,
+ ret, "b", "b", "iq", 1);
+ return ret;
+ case 2:__put_user_asm(*(u16 *)src, (u16 __user *)dst,
+ ret, "w", "w", "ir", 2);
+ return ret;
+ case 4:__put_user_asm(*(u32 *)src, (u32 __user *)dst,
+ ret, "l", "k", "ir", 4);
+ return ret;
+ case 8:__put_user_asm(*(u64 *)src, (u64 __user *)dst,
+ ret, "q", "", "er", 8);
+ return ret;
+ case 10:
+ __put_user_asm(*(u64 *)src, (u64 __user *)dst,
+ ret, "q", "", "er", 10);
+ if (unlikely(ret))
+ return ret;
+ asm("":::"memory");
+ __put_user_asm(4[(u16 *)src], 4 + (u16 __user *)dst,
+ ret, "w", "w", "ir", 2);
+ return ret;
+ case 16:
+ __put_user_asm(*(u64 *)src, (u64 __user *)dst,
+ ret, "q", "", "er", 16);
+ if (unlikely(ret))
+ return ret;
+ asm("":::"memory");
+ __put_user_asm(1[(u64 *)src], 1 + (u64 __user *)dst,
+ ret, "q", "", "er", 8);
+ return ret;
+ default:
+ return copy_user_generic((__force void *)dst, src, size);
+ }
+}
+
+static __always_inline __must_check
+int __copy_to_user(void __user *dst, const void *src, unsigned size)
+{
+ might_fault();
+ return __copy_to_user_nocheck(dst, src, size);
+}
+
+static __always_inline __must_check
+int __copy_in_user(void __user *dst, const void __user *src, unsigned size)
+{
+ int ret = 0;
+
+ might_fault();
+ if (!__builtin_constant_p(size))
+ return copy_user_generic((__force void *)dst,
+ (__force void *)src, size);
+ switch (size) {
+ case 1: {
+ u8 tmp;
+ __get_user_asm(tmp, (u8 __user *)src,
+ ret, "b", "b", "=q", 1);
+ if (likely(!ret))
+ __put_user_asm(tmp, (u8 __user *)dst,
+ ret, "b", "b", "iq", 1);
+ return ret;
+ }
+ case 2: {
+ u16 tmp;
+ __get_user_asm(tmp, (u16 __user *)src,
+ ret, "w", "w", "=r", 2);
+ if (likely(!ret))
+ __put_user_asm(tmp, (u16 __user *)dst,
+ ret, "w", "w", "ir", 2);
+ return ret;
+ }
+
+ case 4: {
+ u32 tmp;
+ __get_user_asm(tmp, (u32 __user *)src,
+ ret, "l", "k", "=r", 4);
+ if (likely(!ret))
+ __put_user_asm(tmp, (u32 __user *)dst,
+ ret, "l", "k", "ir", 4);
+ return ret;
+ }
+ case 8: {
+ u64 tmp;
+ __get_user_asm(tmp, (u64 __user *)src,
+ ret, "q", "", "=r", 8);
+ if (likely(!ret))
+ __put_user_asm(tmp, (u64 __user *)dst,
+ ret, "q", "", "er", 8);
+ return ret;
+ }
+ default:
+ return copy_user_generic((__force void *)dst,
+ (__force void *)src, size);
+ }
+}
+
+static __must_check __always_inline int
+__copy_from_user_inatomic(void *dst, const void __user *src, unsigned size)
+{
+ return __copy_from_user_nocheck(dst, src, size);
+}
+
+static __must_check __always_inline int
+__copy_to_user_inatomic(void __user *dst, const void *src, unsigned size)
+{
+ return __copy_to_user_nocheck(dst, src, size);
+}
+
+extern long __copy_user_nocache(void *dst, const void __user *src,
+ unsigned size, int zerorest);
+
+static inline int
+__copy_from_user_nocache(void *dst, const void __user *src, unsigned size)
+{
+ might_fault();
+ return __copy_user_nocache(dst, src, size, 1);
+}
+
+static inline int
+__copy_from_user_inatomic_nocache(void *dst, const void __user *src,
+ unsigned size)
+{
+ return __copy_user_nocache(dst, src, size, 0);
+}
+
+unsigned long
+copy_user_handle_tail(char *to, char *from, unsigned len);
+
+#endif /* _ASM_X86_UACCESS_64_H */
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