pmem, x86: move x86 PMEM API to new pmem.h header

Move the x86 PMEM API implementation out of asm/cacheflush.h and into
its own header asm/pmem.h.  This will allow members of the PMEM API to
be more easily identified on this and other architectures.

Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Ross Zwisler 2015-08-18 13:55:36 -06:00 committed by Dan Williams
parent 708ab62bef
commit 4060352656
4 changed files with 94 additions and 72 deletions

View File

@ -6161,6 +6161,7 @@ Q: https://patchwork.kernel.org/project/linux-nvdimm/list/
S: Supported
F: drivers/nvdimm/pmem.c
F: include/linux/pmem.h
F: arch/*/include/asm/pmem.h
LINUX FOR IBM pSERIES (RS/6000)
M: Paul Mackerras <paulus@au.ibm.com>

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@ -109,75 +109,4 @@ static inline int rodata_test(void)
}
#endif
#ifdef ARCH_HAS_NOCACHE_UACCESS
/**
* arch_memcpy_to_pmem - copy data to persistent memory
* @dst: destination buffer for the copy
* @src: source buffer for the copy
* @n: length of the copy in bytes
*
* Copy data to persistent memory media via non-temporal stores so that
* a subsequent arch_wmb_pmem() can flush cpu and memory controller
* write buffers to guarantee durability.
*/
static inline void arch_memcpy_to_pmem(void __pmem *dst, const void *src,
size_t n)
{
int unwritten;
/*
* We are copying between two kernel buffers, if
* __copy_from_user_inatomic_nocache() returns an error (page
* fault) we would have already reported a general protection fault
* before the WARN+BUG.
*/
unwritten = __copy_from_user_inatomic_nocache((void __force *) dst,
(void __user *) src, n);
if (WARN(unwritten, "%s: fault copying %p <- %p unwritten: %d\n",
__func__, dst, src, unwritten))
BUG();
}
/**
* arch_wmb_pmem - synchronize writes to persistent memory
*
* After a series of arch_memcpy_to_pmem() operations this drains data
* from cpu write buffers and any platform (memory controller) buffers
* to ensure that written data is durable on persistent memory media.
*/
static inline void arch_wmb_pmem(void)
{
/*
* wmb() to 'sfence' all previous writes such that they are
* architecturally visible to 'pcommit'. Note, that we've
* already arranged for pmem writes to avoid the cache via
* arch_memcpy_to_pmem().
*/
wmb();
pcommit_sfence();
}
static inline bool __arch_has_wmb_pmem(void)
{
#ifdef CONFIG_X86_64
/*
* We require that wmb() be an 'sfence', that is only guaranteed on
* 64-bit builds
*/
return static_cpu_has(X86_FEATURE_PCOMMIT);
#else
return false;
#endif
}
#else /* ARCH_HAS_NOCACHE_UACCESS i.e. ARCH=um */
extern void arch_memcpy_to_pmem(void __pmem *dst, const void *src, size_t n);
extern void arch_wmb_pmem(void);
static inline bool __arch_has_wmb_pmem(void)
{
return false;
}
#endif
#endif /* _ASM_X86_CACHEFLUSH_H */

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@ -0,0 +1,92 @@
/*
* Copyright(c) 2015 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*/
#ifndef __ASM_X86_PMEM_H__
#define __ASM_X86_PMEM_H__
#include <linux/uaccess.h>
#include <asm/cacheflush.h>
#include <asm/cpufeature.h>
#include <asm/special_insns.h>
#ifdef ARCH_HAS_NOCACHE_UACCESS
/**
* arch_memcpy_to_pmem - copy data to persistent memory
* @dst: destination buffer for the copy
* @src: source buffer for the copy
* @n: length of the copy in bytes
*
* Copy data to persistent memory media via non-temporal stores so that
* a subsequent arch_wmb_pmem() can flush cpu and memory controller
* write buffers to guarantee durability.
*/
static inline void arch_memcpy_to_pmem(void __pmem *dst, const void *src,
size_t n)
{
int unwritten;
/*
* We are copying between two kernel buffers, if
* __copy_from_user_inatomic_nocache() returns an error (page
* fault) we would have already reported a general protection fault
* before the WARN+BUG.
*/
unwritten = __copy_from_user_inatomic_nocache((void __force *) dst,
(void __user *) src, n);
if (WARN(unwritten, "%s: fault copying %p <- %p unwritten: %d\n",
__func__, dst, src, unwritten))
BUG();
}
/**
* arch_wmb_pmem - synchronize writes to persistent memory
*
* After a series of arch_memcpy_to_pmem() operations this drains data
* from cpu write buffers and any platform (memory controller) buffers
* to ensure that written data is durable on persistent memory media.
*/
static inline void arch_wmb_pmem(void)
{
/*
* wmb() to 'sfence' all previous writes such that they are
* architecturally visible to 'pcommit'. Note, that we've
* already arranged for pmem writes to avoid the cache via
* arch_memcpy_to_pmem().
*/
wmb();
pcommit_sfence();
}
static inline bool __arch_has_wmb_pmem(void)
{
#ifdef CONFIG_X86_64
/*
* We require that wmb() be an 'sfence', that is only guaranteed on
* 64-bit builds
*/
return static_cpu_has(X86_FEATURE_PCOMMIT);
#else
return false;
#endif
}
#else /* ARCH_HAS_NOCACHE_UACCESS i.e. ARCH=um */
extern void arch_memcpy_to_pmem(void __pmem *dst, const void *src, size_t n);
extern void arch_wmb_pmem(void);
static inline bool __arch_has_wmb_pmem(void)
{
return false;
}
#endif
#endif /* __ASM_X86_PMEM_H__ */

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@ -16,7 +16,7 @@
#include <linux/io.h>
#ifdef CONFIG_ARCH_HAS_PMEM_API
#include <asm/cacheflush.h>
#include <asm/pmem.h>
#else
static inline void arch_wmb_pmem(void)
{