Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 206 insertions, 0 deletions

diff --git a/arch/x86/lib/getuser.S b/arch/x86/lib/getuser.S
new file mode 100644
index 000000000..b70d98d79
--- /dev/null
+++ b/arch/x86/lib/getuser.S
@@ -0,0 +1,206 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * __get_user functions.
+ *
+ * (C) Copyright 1998 Linus Torvalds
+ * (C) Copyright 2005 Andi Kleen
+ * (C) Copyright 2008 Glauber Costa
+ *
+ * These functions have a non-standard call interface
+ * to make them more efficient, especially as they
+ * return an error value in addition to the "real"
+ * return value.
+ */
+
+/*
+ * __get_user_X
+ *
+ * Inputs:	%[r|e]ax contains the address.
+ *
+ * Outputs:	%[r|e]ax is error code (0 or -EFAULT)
+ *		%[r|e]dx contains zero-extended value
+ *		%ecx contains the high half for 32-bit __get_user_8
+ *
+ *
+ * These functions should not modify any other registers,
+ * as they get called from within inline assembly.
+ */
+
+#include <linux/linkage.h>
+#include <asm/page_types.h>
+#include <asm/errno.h>
+#include <asm/asm-offsets.h>
+#include <asm/thread_info.h>
+#include <asm/asm.h>
+#include <asm/smap.h>
+#include <asm/export.h>
+
+#define ASM_BARRIER_NOSPEC ALTERNATIVE "", "lfence", X86_FEATURE_LFENCE_RDTSC
+
+#ifdef CONFIG_X86_5LEVEL
+#define LOAD_TASK_SIZE_MINUS_N(n) \
+	ALTERNATIVE __stringify(mov $((1 << 47) - 4096 - (n)),%rdx), \
+		    __stringify(mov $((1 << 56) - 4096 - (n)),%rdx), X86_FEATURE_LA57
+#else
+#define LOAD_TASK_SIZE_MINUS_N(n) \
+	mov $(TASK_SIZE_MAX - (n)),%_ASM_DX
+#endif
+
+	.text
+SYM_FUNC_START(__get_user_1)
+	LOAD_TASK_SIZE_MINUS_N(0)
+	cmp %_ASM_DX,%_ASM_AX
+	jae bad_get_user
+	sbb %_ASM_DX, %_ASM_DX		/* array_index_mask_nospec() */
+	and %_ASM_DX, %_ASM_AX
+	ASM_STAC
+1:	movzbl (%_ASM_AX),%edx
+	xor %eax,%eax
+	ASM_CLAC
+	RET
+SYM_FUNC_END(__get_user_1)
+EXPORT_SYMBOL(__get_user_1)
+
+SYM_FUNC_START(__get_user_2)
+	LOAD_TASK_SIZE_MINUS_N(1)
+	cmp %_ASM_DX,%_ASM_AX
+	jae bad_get_user
+	sbb %_ASM_DX, %_ASM_DX		/* array_index_mask_nospec() */
+	and %_ASM_DX, %_ASM_AX
+	ASM_STAC
+2:	movzwl (%_ASM_AX),%edx
+	xor %eax,%eax
+	ASM_CLAC
+	RET
+SYM_FUNC_END(__get_user_2)
+EXPORT_SYMBOL(__get_user_2)
+
+SYM_FUNC_START(__get_user_4)
+	LOAD_TASK_SIZE_MINUS_N(3)
+	cmp %_ASM_DX,%_ASM_AX
+	jae bad_get_user
+	sbb %_ASM_DX, %_ASM_DX		/* array_index_mask_nospec() */
+	and %_ASM_DX, %_ASM_AX
+	ASM_STAC
+3:	movl (%_ASM_AX),%edx
+	xor %eax,%eax
+	ASM_CLAC
+	RET
+SYM_FUNC_END(__get_user_4)
+EXPORT_SYMBOL(__get_user_4)
+
+SYM_FUNC_START(__get_user_8)
+#ifdef CONFIG_X86_64
+	LOAD_TASK_SIZE_MINUS_N(7)
+	cmp %_ASM_DX,%_ASM_AX
+	jae bad_get_user
+	sbb %_ASM_DX, %_ASM_DX		/* array_index_mask_nospec() */
+	and %_ASM_DX, %_ASM_AX
+	ASM_STAC
+4:	movq (%_ASM_AX),%rdx
+	xor %eax,%eax
+	ASM_CLAC
+	RET
+#else
+	LOAD_TASK_SIZE_MINUS_N(7)
+	cmp %_ASM_DX,%_ASM_AX
+	jae bad_get_user_8
+	sbb %_ASM_DX, %_ASM_DX		/* array_index_mask_nospec() */
+	and %_ASM_DX, %_ASM_AX
+	ASM_STAC
+4:	movl (%_ASM_AX),%edx
+5:	movl 4(%_ASM_AX),%ecx
+	xor %eax,%eax
+	ASM_CLAC
+	RET
+#endif
+SYM_FUNC_END(__get_user_8)
+EXPORT_SYMBOL(__get_user_8)
+
+/* .. and the same for __get_user, just without the range checks */
+SYM_FUNC_START(__get_user_nocheck_1)
+	ASM_STAC
+	ASM_BARRIER_NOSPEC
+6:	movzbl (%_ASM_AX),%edx
+	xor %eax,%eax
+	ASM_CLAC
+	RET
+SYM_FUNC_END(__get_user_nocheck_1)
+EXPORT_SYMBOL(__get_user_nocheck_1)
+
+SYM_FUNC_START(__get_user_nocheck_2)
+	ASM_STAC
+	ASM_BARRIER_NOSPEC
+7:	movzwl (%_ASM_AX),%edx
+	xor %eax,%eax
+	ASM_CLAC
+	RET
+SYM_FUNC_END(__get_user_nocheck_2)
+EXPORT_SYMBOL(__get_user_nocheck_2)
+
+SYM_FUNC_START(__get_user_nocheck_4)
+	ASM_STAC
+	ASM_BARRIER_NOSPEC
+8:	movl (%_ASM_AX),%edx
+	xor %eax,%eax
+	ASM_CLAC
+	RET
+SYM_FUNC_END(__get_user_nocheck_4)
+EXPORT_SYMBOL(__get_user_nocheck_4)
+
+SYM_FUNC_START(__get_user_nocheck_8)
+	ASM_STAC
+	ASM_BARRIER_NOSPEC
+#ifdef CONFIG_X86_64
+9:	movq (%_ASM_AX),%rdx
+#else
+9:	movl (%_ASM_AX),%edx
+10:	movl 4(%_ASM_AX),%ecx
+#endif
+	xor %eax,%eax
+	ASM_CLAC
+	RET
+SYM_FUNC_END(__get_user_nocheck_8)
+EXPORT_SYMBOL(__get_user_nocheck_8)
+
+
+SYM_CODE_START_LOCAL(.Lbad_get_user_clac)
+	ASM_CLAC
+bad_get_user:
+	xor %edx,%edx
+	mov $(-EFAULT),%_ASM_AX
+	RET
+SYM_CODE_END(.Lbad_get_user_clac)
+
+#ifdef CONFIG_X86_32
+SYM_CODE_START_LOCAL(.Lbad_get_user_8_clac)
+	ASM_CLAC
+bad_get_user_8:
+	xor %edx,%edx
+	xor %ecx,%ecx
+	mov $(-EFAULT),%_ASM_AX
+	RET
+SYM_CODE_END(.Lbad_get_user_8_clac)
+#endif
+
+/* get_user */
+	_ASM_EXTABLE_UA(1b, .Lbad_get_user_clac)
+	_ASM_EXTABLE_UA(2b, .Lbad_get_user_clac)
+	_ASM_EXTABLE_UA(3b, .Lbad_get_user_clac)
+#ifdef CONFIG_X86_64
+	_ASM_EXTABLE_UA(4b, .Lbad_get_user_clac)
+#else
+	_ASM_EXTABLE_UA(4b, .Lbad_get_user_8_clac)
+	_ASM_EXTABLE_UA(5b, .Lbad_get_user_8_clac)
+#endif
+
+/* __get_user */
+	_ASM_EXTABLE_UA(6b, .Lbad_get_user_clac)
+	_ASM_EXTABLE_UA(7b, .Lbad_get_user_clac)
+	_ASM_EXTABLE_UA(8b, .Lbad_get_user_clac)
+#ifdef CONFIG_X86_64
+	_ASM_EXTABLE_UA(9b, .Lbad_get_user_clac)
+#else
+	_ASM_EXTABLE_UA(9b, .Lbad_get_user_8_clac)
+	_ASM_EXTABLE_UA(10b, .Lbad_get_user_8_clac)
+#endif