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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/arm64/lib/copy_from_user.S
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/arm64/lib/copy_from_user.S')
-rw-r--r--arch/arm64/lib/copy_from_user.S73
1 files changed, 73 insertions, 0 deletions
diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S
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+++ b/arch/arm64/lib/copy_from_user.S
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+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ */
+
+#include <linux/linkage.h>
+
+#include <asm/asm-uaccess.h>
+#include <asm/assembler.h>
+#include <asm/cache.h>
+
+/*
+ * Copy from user space to a kernel buffer (alignment handled by the hardware)
+ *
+ * Parameters:
+ * x0 - to
+ * x1 - from
+ * x2 - n
+ * Returns:
+ * x0 - bytes not copied
+ */
+
+ .macro ldrb1 reg, ptr, val
+ user_ldst 9998f, ldtrb, \reg, \ptr, \val
+ .endm
+
+ .macro strb1 reg, ptr, val
+ strb \reg, [\ptr], \val
+ .endm
+
+ .macro ldrh1 reg, ptr, val
+ user_ldst 9997f, ldtrh, \reg, \ptr, \val
+ .endm
+
+ .macro strh1 reg, ptr, val
+ strh \reg, [\ptr], \val
+ .endm
+
+ .macro ldr1 reg, ptr, val
+ user_ldst 9997f, ldtr, \reg, \ptr, \val
+ .endm
+
+ .macro str1 reg, ptr, val
+ str \reg, [\ptr], \val
+ .endm
+
+ .macro ldp1 reg1, reg2, ptr, val
+ user_ldp 9997f, \reg1, \reg2, \ptr, \val
+ .endm
+
+ .macro stp1 reg1, reg2, ptr, val
+ stp \reg1, \reg2, [\ptr], \val
+ .endm
+
+end .req x5
+srcin .req x15
+SYM_FUNC_START(__arch_copy_from_user)
+ add end, x0, x2
+ mov srcin, x1
+#include "copy_template.S"
+ mov x0, #0 // Nothing to copy
+ ret
+
+ // Exception fixups
+9997: cmp dst, dstin
+ b.ne 9998f
+ // Before being absolutely sure we couldn't copy anything, try harder
+USER(9998f, ldtrb tmp1w, [srcin])
+ strb tmp1w, [dst], #1
+9998: sub x0, end, dst // bytes not copied
+ ret
+SYM_FUNC_END(__arch_copy_from_user)
+EXPORT_SYMBOL(__arch_copy_from_user)