[1/3] uapi: introduce uapi-friendly macros for GENMASK

Commit Message

Paolo Bonzini Jan. 31, 2024, 10:50 p.m. UTC

Move __GENMASK and __GENMASK_ULL from include/ to include/uapi/ so that they can
be used to define masks in userspace API headers.  Compared to what is already
in include/linux/bits.h, the definitions need to use the uglified versions of
UL(), ULL(), BITS_PER_LONG and BITS_PER_LONG_LONG (which did not even exist),
but otherwise expand to the same content.

Signed-off-by: Paolo Bonzini <[e-mail]>
---
 include/linux/bits.h                   |  8 +-------
 include/uapi/asm-generic/bitsperlong.h |  4 ++++
 include/uapi/linux/bits.h              | 15 +++++++++++++++
 3 files changed, 20 insertions(+), 7 deletions(-)
 create mode 100644 include/uapi/linux/bits.h

Patch

diff --git a/include/linux/bits.h b/include/linux/bits.h
index 7c0cf5031abe..0eb24d21aac2 100644
--- a/include/linux/bits.h
+++ b/include/linux/bits.h
@@ -4,6 +4,7 @@ 
 
 #include <linux/const.h>
 #include <vdso/bits.h>
+#include <uapi/linux/bits.h>
 #include <asm/bitsperlong.h>
 
 #define BIT_MASK(nr)		(UL(1) << ((nr) % BITS_PER_LONG))
@@ -30,15 +31,8 @@ 
 #define GENMASK_INPUT_CHECK(h, l) 0
 #endif
 
-#define __GENMASK(h, l) \
-	(((~UL(0)) - (UL(1) << (l)) + 1) & \
-	 (~UL(0) >> (BITS_PER_LONG - 1 - (h))))
 #define GENMASK(h, l) \
 	(GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
-
-#define __GENMASK_ULL(h, l) \
-	(((~ULL(0)) - (ULL(1) << (l)) + 1) & \
-	 (~ULL(0) >> (BITS_PER_LONG_LONG - 1 - (h))))
 #define GENMASK_ULL(h, l) \
 	(GENMASK_INPUT_CHECK(h, l) + __GENMASK_ULL(h, l))
 
diff --git a/include/uapi/asm-generic/bitsperlong.h b/include/uapi/asm-generic/bitsperlong.h
index 352cb81947b8..fadb3f857f28 100644
--- a/include/uapi/asm-generic/bitsperlong.h
+++ b/include/uapi/asm-generic/bitsperlong.h
@@ -24,4 +24,8 @@ 
 #endif
 #endif
 
+#ifndef __BITS_PER_LONG_LONG
+#define __BITS_PER_LONG_LONG 64
+#endif
+
 #endif /* _UAPI__ASM_GENERIC_BITS_PER_LONG */
diff --git a/include/uapi/linux/bits.h b/include/uapi/linux/bits.h
new file mode 100644
index 000000000000..3c2a101986a3
--- /dev/null
+++ b/include/uapi/linux/bits.h
@@ -0,0 +1,15 @@ 
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/* bits.h: Macros for dealing with bitmasks.  */
+
+#ifndef _UAPI_LINUX_BITS_H
+#define _UAPI_LINUX_BITS_H
+
+#define __GENMASK(h, l) \
+        (((~_UL(0)) - (_UL(1) << (l)) + 1) & \
+         (~_UL(0) >> (__BITS_PER_LONG - 1 - (h))))
+
+#define __GENMASK_ULL(h, l) \
+        (((~_ULL(0)) - (_ULL(1) << (l)) + 1) & \
+         (~_ULL(0) >> (__BITS_PER_LONG_LONG - 1 - (h))))
+
+#endif /* _UAPI_LINUX_BITS_H */