From e836a256e8fd579c9d7a3685f22981225a1ca451 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Wed, 12 Aug 2015 18:42:56 -0400 Subject: pmem: convert to generic memremap Kill arch_memremap_pmem() and just let the architecture specify the flags to be passed to memremap(). Default to writethrough by default. Suggested-by: Christoph Hellwig Reviewed-by: Christoph Hellwig Reviewed-by: Ross Zwisler Signed-off-by: Dan Williams --- include/linux/pmem.h | 28 +++++++++------------------- 1 file changed, 9 insertions(+), 19 deletions(-) (limited to 'include/linux/pmem.h') diff --git a/include/linux/pmem.h b/include/linux/pmem.h index d2114045a6c4..093c35ecefcc 100644 --- a/include/linux/pmem.h +++ b/include/linux/pmem.h @@ -28,12 +28,6 @@ static inline bool __arch_has_wmb_pmem(void) return false; } -static inline void __pmem *arch_memremap_pmem(resource_size_t offset, - unsigned long size) -{ - return NULL; -} - static inline void arch_memcpy_to_pmem(void __pmem *dst, const void *src, size_t n) { @@ -43,8 +37,8 @@ static inline void arch_memcpy_to_pmem(void __pmem *dst, const void *src, /* * Architectures that define ARCH_HAS_PMEM_API must provide - * implementations for arch_memremap_pmem(), arch_memcpy_to_pmem(), - * arch_wmb_pmem(), and __arch_has_wmb_pmem(). + * implementations for arch_memcpy_to_pmem(), arch_wmb_pmem(), and + * __arch_has_wmb_pmem(). */ static inline void memcpy_from_pmem(void *dst, void __pmem const *src, size_t size) @@ -54,7 +48,7 @@ static inline void memcpy_from_pmem(void *dst, void __pmem const *src, size_t si static inline void memunmap_pmem(void __pmem *addr) { - iounmap((void __force __iomem *) addr); + memunmap((void __force *) addr); } /** @@ -85,18 +79,12 @@ static inline bool arch_has_pmem_api(void) * default_memremap_pmem + default_memcpy_to_pmem is sufficient for * making data durable relative to i/o completion. */ -static void default_memcpy_to_pmem(void __pmem *dst, const void *src, +static inline void default_memcpy_to_pmem(void __pmem *dst, const void *src, size_t size) { memcpy((void __force *) dst, src, size); } -static void __pmem *default_memremap_pmem(resource_size_t offset, - unsigned long size) -{ - return (void __pmem __force *)ioremap_wt(offset, size); -} - /** * memremap_pmem - map physical persistent memory for pmem api * @offset: physical address of persistent memory @@ -112,9 +100,11 @@ static void __pmem *default_memremap_pmem(resource_size_t offset, static inline void __pmem *memremap_pmem(resource_size_t offset, unsigned long size) { - if (arch_has_pmem_api()) - return arch_memremap_pmem(offset, size); - return default_memremap_pmem(offset, size); +#ifdef ARCH_MEMREMAP_PMEM + return (void __pmem *) memremap(offset, size, ARCH_MEMREMAP_PMEM); +#else + return (void __pmem *) memremap(offset, size, MEMREMAP_WT); +#endif } /** -- cgit v1.2.3 From 708ab62bef1ed3a3cf065a4138bd87f5d083cfeb Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 10 Aug 2015 23:07:08 -0400 Subject: pmem: switch to devm_ allocations Signed-off-by: Christoph Hellwig [djbw: tools/testing/nvdimm/ and memunmap_pmem support] Reviewed-by: Ross Zwisler Signed-off-by: Dan Williams --- include/linux/pmem.h | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) (limited to 'include/linux/pmem.h') diff --git a/include/linux/pmem.h b/include/linux/pmem.h index 093c35ecefcc..20c367cd76e6 100644 --- a/include/linux/pmem.h +++ b/include/linux/pmem.h @@ -46,9 +46,9 @@ static inline void memcpy_from_pmem(void *dst, void __pmem const *src, size_t si memcpy(dst, (void __force const *) src, size); } -static inline void memunmap_pmem(void __pmem *addr) +static inline void memunmap_pmem(struct device *dev, void __pmem *addr) { - memunmap((void __force *) addr); + devm_memunmap(dev, (void __force *) addr); } /** @@ -97,13 +97,15 @@ static inline void default_memcpy_to_pmem(void __pmem *dst, const void *src, * wmb_pmem() arrange for the data to be written through the * cache to persistent media. */ -static inline void __pmem *memremap_pmem(resource_size_t offset, - unsigned long size) +static inline void __pmem *memremap_pmem(struct device *dev, + resource_size_t offset, unsigned long size) { #ifdef ARCH_MEMREMAP_PMEM - return (void __pmem *) memremap(offset, size, ARCH_MEMREMAP_PMEM); + return (void __pmem *) devm_memremap(dev, offset, size, + ARCH_MEMREMAP_PMEM); #else - return (void __pmem *) memremap(offset, size, MEMREMAP_WT); + return (void __pmem *) devm_memremap(dev, offset, size, + MEMREMAP_WT); #endif } -- cgit v1.2.3 From 40603526569b304dd92f720f2f8ab11e828ea145 Mon Sep 17 00:00:00 2001 From: Ross Zwisler Date: Tue, 18 Aug 2015 13:55:36 -0600 Subject: 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 Suggested-by: Christoph Hellwig Reviewed-by: Christoph Hellwig Signed-off-by: Dan Williams --- include/linux/pmem.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/pmem.h') diff --git a/include/linux/pmem.h b/include/linux/pmem.h index 20c367cd76e6..c2af613ec297 100644 --- a/include/linux/pmem.h +++ b/include/linux/pmem.h @@ -16,7 +16,7 @@ #include #ifdef CONFIG_ARCH_HAS_PMEM_API -#include +#include #else static inline void arch_wmb_pmem(void) { -- cgit v1.2.3 From 18279b467a9d89afe44afbc19d768e834dbf4545 Mon Sep 17 00:00:00 2001 From: Ross Zwisler Date: Tue, 18 Aug 2015 13:55:37 -0600 Subject: pmem: remove layer when calling arch_has_wmb_pmem() Prior to this change arch_has_wmb_pmem() was only called by arch_has_pmem_api(). Both arch_has_wmb_pmem() and arch_has_pmem_api() checked to make sure that CONFIG_ARCH_HAS_PMEM_API was enabled. Instead, remove the old arch_has_wmb_pmem() wrapper to be rid of one extra layer of indirection and the redundant CONFIG_ARCH_HAS_PMEM_API check. Rename __arch_has_wmb_pmem() to arch_has_wmb_pmem() since we no longer have a wrapper, and just have arch_has_pmem_api() call the architecture specific arch_has_wmb_pmem() directly. Signed-off-by: Ross Zwisler Reviewed-by: Christoph Hellwig Signed-off-by: Dan Williams --- include/linux/pmem.h | 13 +++---------- 1 file changed, 3 insertions(+), 10 deletions(-) (limited to 'include/linux/pmem.h') diff --git a/include/linux/pmem.h b/include/linux/pmem.h index c2af613ec297..a0706ea04efd 100644 --- a/include/linux/pmem.h +++ b/include/linux/pmem.h @@ -23,7 +23,7 @@ static inline void arch_wmb_pmem(void) BUG(); } -static inline bool __arch_has_wmb_pmem(void) +static inline bool arch_has_wmb_pmem(void) { return false; } @@ -38,7 +38,7 @@ static inline void arch_memcpy_to_pmem(void __pmem *dst, const void *src, /* * Architectures that define ARCH_HAS_PMEM_API must provide * implementations for arch_memcpy_to_pmem(), arch_wmb_pmem(), and - * __arch_has_wmb_pmem(). + * arch_has_wmb_pmem(). */ static inline void memcpy_from_pmem(void *dst, void __pmem const *src, size_t size) @@ -52,7 +52,7 @@ static inline void memunmap_pmem(struct device *dev, void __pmem *addr) } /** - * arch_has_wmb_pmem - true if wmb_pmem() ensures durability + * arch_has_pmem_api - true if wmb_pmem() ensures durability * * For a given cpu implementation within an architecture it is possible * that wmb_pmem() resolves to a nop. In the case this returns @@ -60,13 +60,6 @@ static inline void memunmap_pmem(struct device *dev, void __pmem *addr) * fall back to a different data consistency model, or otherwise notify * the user. */ -static inline bool arch_has_wmb_pmem(void) -{ - if (IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API)) - return __arch_has_wmb_pmem(); - return false; -} - static inline bool arch_has_pmem_api(void) { return IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API) && arch_has_wmb_pmem(); -- cgit v1.2.3 From 5de490daec8b6354b90d5c9d3e2415b195f5adb6 Mon Sep 17 00:00:00 2001 From: Ross Zwisler Date: Tue, 18 Aug 2015 13:55:39 -0600 Subject: pmem: add copy_from_iter_pmem() and clear_pmem() Add support for two new PMEM APIs, copy_from_iter_pmem() and clear_pmem(). copy_from_iter_pmem() is used to copy data from an iterator into a PMEM buffer. clear_pmem() zeros a PMEM memory range. Both of these new APIs must be explicitly ordered using a wmb_pmem() function call and are implemented in such a way that the wmb_pmem() will make the stores to PMEM durable. Because both APIs are unordered they can be called as needed without introducing any unwanted memory barriers. Signed-off-by: Ross Zwisler Signed-off-by: Dan Williams --- include/linux/pmem.h | 64 ++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 62 insertions(+), 2 deletions(-) (limited to 'include/linux/pmem.h') diff --git a/include/linux/pmem.h b/include/linux/pmem.h index a0706ea04efd..a9d84bf335ee 100644 --- a/include/linux/pmem.h +++ b/include/linux/pmem.h @@ -14,6 +14,7 @@ #define __PMEM_H__ #include +#include #ifdef CONFIG_ARCH_HAS_PMEM_API #include @@ -33,12 +34,24 @@ static inline void arch_memcpy_to_pmem(void __pmem *dst, const void *src, { BUG(); } + +static inline size_t arch_copy_from_iter_pmem(void __pmem *addr, size_t bytes, + struct iov_iter *i) +{ + BUG(); + return 0; +} + +static inline void arch_clear_pmem(void __pmem *addr, size_t size) +{ + BUG(); +} #endif /* * Architectures that define ARCH_HAS_PMEM_API must provide - * implementations for arch_memcpy_to_pmem(), arch_wmb_pmem(), and - * arch_has_wmb_pmem(). + * implementations for arch_memcpy_to_pmem(), arch_wmb_pmem(), + * arch_copy_from_iter_pmem(), arch_clear_pmem() and arch_has_wmb_pmem(). */ static inline void memcpy_from_pmem(void *dst, void __pmem const *src, size_t size) @@ -78,6 +91,20 @@ static inline void default_memcpy_to_pmem(void __pmem *dst, const void *src, memcpy((void __force *) dst, src, size); } +static inline size_t default_copy_from_iter_pmem(void __pmem *addr, + size_t bytes, struct iov_iter *i) +{ + return copy_from_iter_nocache((void __force *)addr, bytes, i); +} + +static inline void default_clear_pmem(void __pmem *addr, size_t size) +{ + if (size == PAGE_SIZE && ((unsigned long)addr & ~PAGE_MASK) == 0) + clear_page((void __force *)addr); + else + memset((void __force *)addr, 0, size); +} + /** * memremap_pmem - map physical persistent memory for pmem api * @offset: physical address of persistent memory @@ -134,4 +161,37 @@ static inline void wmb_pmem(void) if (arch_has_pmem_api()) arch_wmb_pmem(); } + +/** + * copy_from_iter_pmem - copy data from an iterator to PMEM + * @addr: PMEM destination address + * @bytes: number of bytes to copy + * @i: iterator with source data + * + * Copy data from the iterator 'i' to the PMEM buffer starting at 'addr'. + * This function requires explicit ordering with a wmb_pmem() call. + */ +static inline size_t copy_from_iter_pmem(void __pmem *addr, size_t bytes, + struct iov_iter *i) +{ + if (arch_has_pmem_api()) + return arch_copy_from_iter_pmem(addr, bytes, i); + return default_copy_from_iter_pmem(addr, bytes, i); +} + +/** + * clear_pmem - zero a PMEM memory range + * @addr: virtual start address + * @size: number of bytes to zero + * + * Write zeros into the memory range starting at 'addr' for 'size' bytes. + * This function requires explicit ordering with a wmb_pmem() call. + */ +static inline void clear_pmem(void __pmem *addr, size_t size) +{ + if (arch_has_pmem_api()) + arch_clear_pmem(addr, size); + else + default_clear_pmem(addr, size); +} #endif /* __PMEM_H__ */ -- cgit v1.2.3 From 96601adb745186ccbcf5b078d4756f13381ec2af Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Mon, 24 Aug 2015 18:29:38 -0400 Subject: x86, pmem: clarify that ARCH_HAS_PMEM_API implies PMEM mapped WB Given that a write-back (WB) mapping plus non-temporal stores is expected to be the most efficient way to access PMEM, update the definition of ARCH_HAS_PMEM_API to imply arch support for WB-mapped-PMEM. This is needed as a pre-requisite for adding PMEM to the direct map and mapping it with struct page. The above clarification for X86_64 means that memcpy_to_pmem() is permitted to use the non-temporal arch_memcpy_to_pmem() rather than needlessly fall back to default_memcpy_to_pmem() when the pcommit instruction is not available. When arch_memcpy_to_pmem() is not guaranteed to flush writes out of cache, i.e. on older X86_32 implementations where non-temporal stores may just dirty cache, ARCH_HAS_PMEM_API is simply disabled. The default fall back for persistent memory handling remains. Namely, map it with the WT (write-through) cache-type and hope for the best. arch_has_pmem_api() is updated to only indicate whether the arch provides the proper helpers to meet the minimum "writes are visible outside the cache hierarchy after memcpy_to_pmem() + wmb_pmem()". Code that cares whether wmb_pmem() actually flushes writes to pmem must now call arch_has_wmb_pmem() directly. Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Reviewed-by: Ross Zwisler [hch: set ARCH_HAS_PMEM_API=n on x86_32] Reviewed-by: Christoph Hellwig [toshi: x86_32 compile fixes] Signed-off-by: Toshi Kani Signed-off-by: Dan Williams --- include/linux/pmem.h | 36 ++++++++++++++++++++++-------------- 1 file changed, 22 insertions(+), 14 deletions(-) (limited to 'include/linux/pmem.h') diff --git a/include/linux/pmem.h b/include/linux/pmem.h index a9d84bf335ee..85f810b33917 100644 --- a/include/linux/pmem.h +++ b/include/linux/pmem.h @@ -17,16 +17,23 @@ #include #ifdef CONFIG_ARCH_HAS_PMEM_API +#define ARCH_MEMREMAP_PMEM MEMREMAP_WB #include #else -static inline void arch_wmb_pmem(void) +#define ARCH_MEMREMAP_PMEM MEMREMAP_WT +/* + * These are simply here to enable compilation, all call sites gate + * calling these symbols with arch_has_pmem_api() and redirect to the + * implementation in asm/pmem.h. + */ +static inline bool __arch_has_wmb_pmem(void) { - BUG(); + return false; } -static inline bool arch_has_wmb_pmem(void) +static inline void arch_wmb_pmem(void) { - return false; + BUG(); } static inline void arch_memcpy_to_pmem(void __pmem *dst, const void *src, @@ -53,7 +60,6 @@ static inline void arch_clear_pmem(void __pmem *addr, size_t size) * implementations for arch_memcpy_to_pmem(), arch_wmb_pmem(), * arch_copy_from_iter_pmem(), arch_clear_pmem() and arch_has_wmb_pmem(). */ - static inline void memcpy_from_pmem(void *dst, void __pmem const *src, size_t size) { memcpy(dst, (void __force const *) src, size); @@ -64,8 +70,13 @@ static inline void memunmap_pmem(struct device *dev, void __pmem *addr) devm_memunmap(dev, (void __force *) addr); } +static inline bool arch_has_pmem_api(void) +{ + return IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API); +} + /** - * arch_has_pmem_api - true if wmb_pmem() ensures durability + * arch_has_wmb_pmem - true if wmb_pmem() ensures durability * * For a given cpu implementation within an architecture it is possible * that wmb_pmem() resolves to a nop. In the case this returns @@ -73,9 +84,9 @@ static inline void memunmap_pmem(struct device *dev, void __pmem *addr) * fall back to a different data consistency model, or otherwise notify * the user. */ -static inline bool arch_has_pmem_api(void) +static inline bool arch_has_wmb_pmem(void) { - return IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API) && arch_has_wmb_pmem(); + return arch_has_pmem_api() && __arch_has_wmb_pmem(); } /* @@ -120,13 +131,8 @@ static inline void default_clear_pmem(void __pmem *addr, size_t size) static inline void __pmem *memremap_pmem(struct device *dev, resource_size_t offset, unsigned long size) { -#ifdef ARCH_MEMREMAP_PMEM return (void __pmem *) devm_memremap(dev, offset, size, ARCH_MEMREMAP_PMEM); -#else - return (void __pmem *) devm_memremap(dev, offset, size, - MEMREMAP_WT); -#endif } /** @@ -158,8 +164,10 @@ static inline void memcpy_to_pmem(void __pmem *dst, const void *src, size_t n) */ static inline void wmb_pmem(void) { - if (arch_has_pmem_api()) + if (arch_has_wmb_pmem()) arch_wmb_pmem(); + else + wmb(); } /** -- cgit v1.2.3