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+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * linux/arch/arm/lib/copy_to_user.S
+ *
+ * Author: Nicolas Pitre
+ * Created: Sep 29, 2005
+ * Copyright: MontaVista Software, Inc.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/unwind.h>
+
+/*
+ * Prototype:
+ *
+ * size_t arm_copy_to_user(void *to, const void *from, size_t n)
+ *
+ * Purpose:
+ *
+ * copy a block to user memory from kernel memory
+ *
+ * Params:
+ *
+ * to = user memory
+ * from = kernel memory
+ * n = number of bytes to copy
+ *
+ * Return value:
+ *
+ * Number of bytes NOT copied.
+ */
+
+#define LDR1W_SHIFT 0
+
+ .macro ldr1w ptr reg abort
+ W(ldr) \reg, [\ptr], #4
+ .endm
+
+ .macro ldr4w ptr reg1 reg2 reg3 reg4 abort
+ ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4}
+ .endm
+
+ .macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
+ ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8}
+ .endm
+
+ .macro ldr1b ptr reg cond=al abort
+ ldrb\cond \reg, [\ptr], #1
+ .endm
+
+#ifdef CONFIG_CPU_USE_DOMAINS
+
+#ifndef CONFIG_THUMB2_KERNEL
+#define STR1W_SHIFT 0
+#else
+#define STR1W_SHIFT 1
+#endif
+
+ .macro str1w ptr reg abort
+ strusr \reg, \ptr, 4, abort=\abort
+ .endm
+
+ .macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
+ str1w \ptr, \reg1, \abort
+ str1w \ptr, \reg2, \abort
+ str1w \ptr, \reg3, \abort
+ str1w \ptr, \reg4, \abort
+ str1w \ptr, \reg5, \abort
+ str1w \ptr, \reg6, \abort
+ str1w \ptr, \reg7, \abort
+ str1w \ptr, \reg8, \abort
+ .endm
+
+#else
+
+#define STR1W_SHIFT 0
+
+ .macro str1w ptr reg abort
+ USERL(\abort, W(str) \reg, [\ptr], #4)
+ .endm
+
+ .macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
+ USERL(\abort, stmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8})
+ .endm
+
+#endif /* CONFIG_CPU_USE_DOMAINS */
+
+ .macro str1b ptr reg cond=al abort
+ strusr \reg, \ptr, 1, \cond, abort=\abort
+ .endm
+
+ .macro enter regs:vararg
+ mov r3, #0
+UNWIND( .save {r0, r2, r3, \regs} )
+ stmdb sp!, {r0, r2, r3, \regs}
+ .endm
+
+ .macro exit regs:vararg
+ add sp, sp, #8
+ ldmfd sp!, {r0, \regs}
+ .endm
+
+ .text
+
+ENTRY(__copy_to_user_std)
+WEAK(arm_copy_to_user)
+#ifdef CONFIG_CPU_SPECTRE
+ ldr r3, =TASK_SIZE
+ uaccess_mask_range_ptr r0, r2, r3, ip
+#endif
+
+#include "copy_template.S"
+
+ENDPROC(arm_copy_to_user)
+ENDPROC(__copy_to_user_std)
+
+ .pushsection .text.fixup,"ax"
+ .align 0
+ copy_abort_preamble
+ ldmfd sp!, {r1, r2, r3}
+ sub r0, r0, r1
+ rsb r0, r0, r2
+ copy_abort_end
+ .popsection