Provide helper macros for fields which represent pointers in kernel-userspace ABI. This facilitates handling of 32-bit user-space by 64-bit kernels by defining those fields as 32-bit 0-padding and 32-bit integer on 32-bit architectures, which allows the kernel to treat those as 64-bit integers. The order of padding and 32-bit integer depends on the endianness.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoy...@efficios.com> CC: "Paul E. McKenney" <paul...@linux.vnet.ibm.com> CC: Peter Zijlstra <pet...@infradead.org> CC: Paul Turner <p...@google.com> CC: Thomas Gleixner <t...@linutronix.de> CC: Andrew Hunter <a...@google.com> CC: Andy Lutomirski <l...@amacapital.net> CC: Andi Kleen <a...@firstfloor.org> CC: Dave Watson <davejwat...@fb.com> CC: Chris Lameter <c...@linux.com> CC: Ingo Molnar <mi...@redhat.com> CC: "H. Peter Anvin" <h...@zytor.com> CC: Ben Maurer <bmau...@fb.com> CC: Steven Rostedt <rost...@goodmis.org> CC: Josh Triplett <j...@joshtriplett.org> CC: Linus Torvalds <torva...@linux-foundation.org> CC: Andrew Morton <a...@linux-foundation.org> CC: Russell King <li...@arm.linux.org.uk> CC: Catalin Marinas <catalin.mari...@arm.com> CC: Will Deacon <will.dea...@arm.com> CC: Michael Kerrisk <mtk.manpa...@gmail.com> CC: Boqun Feng <boqun.f...@gmail.com> CC: linux-...@vger.kernel.org --- Changes since v1: - Public uapi headers use __u32 and __u64 rather than uint32_t and uint64_t. --- include/uapi/linux/types_32_64.h | 67 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) create mode 100644 include/uapi/linux/types_32_64.h diff --git a/include/uapi/linux/types_32_64.h b/include/uapi/linux/types_32_64.h new file mode 100644 index 000000000000..fc9602c318cd --- /dev/null +++ b/include/uapi/linux/types_32_64.h @@ -0,0 +1,67 @@ +#ifndef _UAPI_LINUX_TYPES_32_64_H +#define _UAPI_LINUX_TYPES_32_64_H + +/* + * linux/types_32_64.h + * + * Integer type declaration for pointers across 32-bit and 64-bit systems. + * + * Copyright (c) 2015-2017 Mathieu Desnoyers <mathieu.desnoy...@efficios.com> + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#ifdef __KERNEL__ +# include <linux/types.h> +#else +# include <stdint.h> +#endif + +#include <asm/byteorder.h> + +#ifdef __BYTE_ORDER +# if (__BYTE_ORDER == __BIG_ENDIAN) +# define LINUX_BYTE_ORDER_BIG_ENDIAN +# else +# define LINUX_BYTE_ORDER_LITTLE_ENDIAN +# endif +#else +# ifdef __BIG_ENDIAN +# define LINUX_BYTE_ORDER_BIG_ENDIAN +# else +# define LINUX_BYTE_ORDER_LITTLE_ENDIAN +# endif +#endif + +#ifdef __LP64__ +# define LINUX_FIELD_u32_u64(field) __u64 field +# define LINUX_FIELD_u32_u64_INIT_ONSTACK(field, v) field = (intptr_t)v +#else +# ifdef LINUX_BYTE_ORDER_BIG_ENDIAN +# define LINUX_FIELD_u32_u64(field) __u32 field ## _padding, field +# define LINUX_FIELD_u32_u64_INIT_ONSTACK(field, v) \ + field ## _padding = 0, field = (intptr_t)v +# else +# define LINUX_FIELD_u32_u64(field) __u32 field, field ## _padding +# define LINUX_FIELD_u32_u64_INIT_ONSTACK(field, v) \ + field = (intptr_t)v, field ## _padding = 0 +# endif +#endif + +#endif /* _UAPI_LINUX_TYPES_32_64_H */ -- 2.11.0
