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authorThomas Gleixner <tglx@linutronix.de>2007-10-11 11:20:03 +0200
committerThomas Gleixner <tglx@linutronix.de>2007-10-11 11:20:03 +0200
commit96a388de5dc53a8b234b3fd41f3ae2cedc9ffd42 (patch)
treed947a467aa2da3140279617bc4b9b101640d7bf4 /include/asm-x86/unaligned_64.h
parent27bd0c955648646abf2a353a8371d28c37bcd982 (diff)
i386/x86_64: move headers to include/asm-x86
Move the headers to include/asm-x86 and fixup the header install make rules Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'include/asm-x86/unaligned_64.h')
-rw-r--r--include/asm-x86/unaligned_64.h37
1 files changed, 37 insertions, 0 deletions
diff --git a/include/asm-x86/unaligned_64.h b/include/asm-x86/unaligned_64.h
new file mode 100644
index 00000000000..d4bf78dc6f3
--- /dev/null
+++ b/include/asm-x86/unaligned_64.h
@@ -0,0 +1,37 @@
+#ifndef __X8664_UNALIGNED_H
+#define __X8664_UNALIGNED_H
+
+/*
+ * The x86-64 can do unaligned accesses itself.
+ *
+ * The strange macros are there to make sure these can't
+ * be misused in a way that makes them not work on other
+ * architectures where unaligned accesses aren't as simple.
+ */
+
+/**
+ * get_unaligned - get value from possibly mis-aligned location
+ * @ptr: pointer to value
+ *
+ * This macro should be used for accessing values larger in size than
+ * single bytes at locations that are expected to be improperly aligned,
+ * e.g. retrieving a u16 value from a location not u16-aligned.
+ *
+ * Note that unaligned accesses can be very expensive on some architectures.
+ */
+#define get_unaligned(ptr) (*(ptr))
+
+/**
+ * put_unaligned - put value to a possibly mis-aligned location
+ * @val: value to place
+ * @ptr: pointer to location
+ *
+ * This macro should be used for placing values larger in size than
+ * single bytes at locations that are expected to be improperly aligned,
+ * e.g. writing a u16 value to a location not u16-aligned.
+ *
+ * Note that unaligned accesses can be very expensive on some architectures.
+ */
+#define put_unaligned(val, ptr) ((void)( *(ptr) = (val) ))
+
+#endif