[Qemu-devel] [PATCH v7 01/12] bitops: Add MAKE_64BIT_MASK macro

[Alistair Francis]

Add a macro that creates a 64bit value which has length number of ones
shifted across by the value of shift.

Signed-off-by: Alistair Francis <address@hidden>
Reviewed-by: Alex Bennée <address@hidden>
---
V7:
 - Fixup commit typo
 - Use the method from deposit64()
V5:
 - Re-write to a 64-bit mask instead of ONES()
 - Re-order this patch in the series

 include/qemu/bitops.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/include/qemu/bitops.h b/include/qemu/bitops.h
index 15418a8..98fb005 100644
--- a/include/qemu/bitops.h
+++ b/include/qemu/bitops.h
@@ -24,6 +24,9 @@
 #define BIT_WORD(nr)            ((nr) / BITS_PER_LONG)
 #define BITS_TO_LONGS(nr)       DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
 
+#define MAKE_64BIT_MASK(shift, length) \
+    (((~0ULL) >> (64 - (length))) << (shift))
+
 /**
  * set_bit - Set a bit in memory
  * @nr: the bit to set
-- 
2.7.4