From 89b5c81b75658b7ff66dea6c38a51dfecc9dd508 Mon Sep 17 00:00:00 2001 From: Jagan Teki <jteki@openedev.com> Date: Wed, 21 Oct 2015 16:46:51 +0530 Subject: [PATCH] linux/bitops.h: GENMASK copy from linux GENMASK is used to create a contiguous bitmask([hi:lo]). This patch is a copy from Linux, with below commit details "bitops: Fix shift overflow in GENMASK macros" (sha1: 00b4d9a14125f1e51874def2b9de6092e007412d) Cc: Tom Rini <trini@konsulko.com> Cc: Masahiro Yamada <yamada.m@jp.panasonic.com> Signed-off-by: Jagan Teki <jteki@openedev.com> --- include/asm-generic/bitsperlong.h | 8 ++++++++ include/linux/bitops.h | 11 +++++++++++ 2 files changed, 19 insertions(+) create mode 100644 include/asm-generic/bitsperlong.h diff --git a/include/asm-generic/bitsperlong.h b/include/asm-generic/bitsperlong.h new file mode 100644 index 0000000000..75ee21e86a --- /dev/null +++ b/include/asm-generic/bitsperlong.h @@ -0,0 +1,8 @@ +#ifndef __ASM_GENERIC_BITS_PER_LONG +#define __ASM_GENERIC_BITS_PER_LONG + +#ifndef BITS_PER_LONG_LONG +#define BITS_PER_LONG_LONG 64 +#endif + +#endif /* __ASM_GENERIC_BITS_PER_LONG */ diff --git a/include/linux/bitops.h b/include/linux/bitops.h index e9bb827f42..7b4011f0a3 100644 --- a/include/linux/bitops.h +++ b/include/linux/bitops.h @@ -7,6 +7,17 @@ #define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG)) #define BIT_WORD(nr) ((nr) / BITS_PER_LONG) +/* + * Create a contiguous bitmask starting at bit position @l and ending at + * position @h. For example + * GENMASK_ULL(39, 21) gives us the 64bit vector 0x000000ffffe00000. + */ +#define GENMASK(h, l) \ + (((~0UL) << (l)) & (~0UL >> (BITS_PER_LONG - 1 - (h)))) + +#define GENMASK_ULL(h, l) \ + (((~0ULL) << (l)) & (~0ULL >> (BITS_PER_LONG_LONG - 1 - (h)))) + /* * ffs: find first bit set. This is defined the same way as * the libc and compiler builtin ffs routines, therefore -- 2.39.5