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authorLinus Walleij <linusw@kernel.org>2026-06-30 18:05:56 +0100
committerRussell King <rmk+kernel@armlinux.org.uk>2026-08-05 16:48:11 +0100
commitbb3b2cfeb206f5b10b859e134651b54120e3f530 (patch)
tree6717fcea088ba5c5f15002a48101fa2537135bf2 /include/asm-generic/fprobe.h
downloadlinux-stable-bb3b2cfeb206f5b10b859e134651b54120e3f530.tar.gz
linux-stable-bb3b2cfeb206f5b10b859e134651b54120e3f530.zip
ARM: 9480/1: entry: expand comment in __switch_tografted
As per discussion between the developers in the mail thread linked, expand the comment in __switch_to so that readers of the code understand what is going on. Suggested-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Linus Walleij <linusw@kernel.org>> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Diffstat (limited to 'include/asm-generic/fprobe.h')
-rw-r--r--include/asm-generic/fprobe.h46
1 files changed, 46 insertions, 0 deletions
diff --git a/include/asm-generic/fprobe.h b/include/asm-generic/fprobe.h
new file mode 100644
index 000000000..8659a4dc6
--- /dev/null
+++ b/include/asm-generic/fprobe.h
@@ -0,0 +1,46 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Generic arch dependent fprobe macros.
+ */
+#ifndef __ASM_GENERIC_FPROBE_H__
+#define __ASM_GENERIC_FPROBE_H__
+
+#include <linux/bits.h>
+
+#ifdef CONFIG_64BIT
+/*
+ * Encoding the size and the address of fprobe into one 64bit entry.
+ * The 32bit architectures should use 2 entries to store those info.
+ */
+
+#define ARCH_DEFINE_ENCODE_FPROBE_HEADER
+
+#define FPROBE_HEADER_MSB_SIZE_SHIFT (BITS_PER_LONG - FPROBE_DATA_SIZE_BITS)
+#define FPROBE_HEADER_MSB_MASK \
+ GENMASK(FPROBE_HEADER_MSB_SIZE_SHIFT - 1, 0)
+
+/*
+ * By default, this expects the MSBs in the address of kprobe is 0xf.
+ * If any arch needs another fixed pattern (e.g. s390 is zero filled),
+ * override this.
+ */
+#define FPROBE_HEADER_MSB_PATTERN \
+ GENMASK(BITS_PER_LONG - 1, FPROBE_HEADER_MSB_SIZE_SHIFT)
+
+#define arch_fprobe_header_encodable(fp) \
+ (((unsigned long)(fp) & ~FPROBE_HEADER_MSB_MASK) == \
+ FPROBE_HEADER_MSB_PATTERN)
+
+#define arch_encode_fprobe_header(fp, size) \
+ (((unsigned long)(fp) & FPROBE_HEADER_MSB_MASK) | \
+ ((unsigned long)(size) << FPROBE_HEADER_MSB_SIZE_SHIFT))
+
+#define arch_decode_fprobe_header_size(val) \
+ ((unsigned long)(val) >> FPROBE_HEADER_MSB_SIZE_SHIFT)
+
+#define arch_decode_fprobe_header_fp(val) \
+ ((struct fprobe *)(((unsigned long)(val) & FPROBE_HEADER_MSB_MASK) | \
+ FPROBE_HEADER_MSB_PATTERN))
+#endif /* CONFIG_64BIT */
+
+#endif /* __ASM_GENERIC_FPROBE_H__ */