From 4e4f00a9b51a1c52ebdd728a1caeb3b9fe48c39d Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Mon, 29 May 2017 22:40:44 -0700 Subject: [PATCH] x86, dax, libnvdimm: remove wb_cache_pmem() indirection With all handling of the CONFIG_ARCH_HAS_PMEM_API case being moved to libnvdimm and the pmem driver directly we do not need to provide global wrappers and fallbacks in the CONFIG_ARCH_HAS_PMEM_API=n case. The pmem driver will simply not link to arch_wb_cache_pmem() in that case. Same as before, pmem flushing is only defined for x86_64, via clean_cache_range(), but it is straightforward to add other archs in the future. arch_wb_cache_pmem() is an exported function since the pmem module needs to find it, but it is privately declared in drivers/nvdimm/pmem.h because there are no consumers outside of the pmem driver. Cc: Cc: Jan Kara Cc: Jeff Moyer Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Thomas Gleixner Cc: Oliver O'Halloran Cc: Matthew Wilcox Cc: Ross Zwisler Suggested-by: Christoph Hellwig Signed-off-by: Dan Williams --- arch/x86/include/asm/pmem.h | 21 --------------------- arch/x86/lib/usercopy_64.c | 6 ++++++ drivers/nvdimm/pmem.c | 2 +- drivers/nvdimm/pmem.h | 8 ++++++++ include/linux/pmem.h | 19 ------------------- 5 files changed, 15 insertions(+), 41 deletions(-) diff --git a/arch/x86/include/asm/pmem.h b/arch/x86/include/asm/pmem.h index f4c119d253f3..4759a179aa52 100644 --- a/arch/x86/include/asm/pmem.h +++ b/arch/x86/include/asm/pmem.h @@ -44,27 +44,6 @@ static inline void arch_memcpy_to_pmem(void *dst, const void *src, size_t n) BUG(); } -/** - * arch_wb_cache_pmem - write back a cache range with CLWB - * @vaddr: virtual start address - * @size: number of bytes to write back - * - * Write back a cache range using the CLWB (cache line write back) - * instruction. Note that @size is internally rounded up to be cache - * line size aligned. - */ -static inline void arch_wb_cache_pmem(void *addr, size_t size) -{ - u16 x86_clflush_size = boot_cpu_data.x86_clflush_size; - unsigned long clflush_mask = x86_clflush_size - 1; - void *vend = addr + size; - void *p; - - for (p = (void *)((unsigned long)addr & ~clflush_mask); - p < vend; p += x86_clflush_size) - clwb(p); -} - static inline void arch_invalidate_pmem(void *addr, size_t size) { clflush_cache_range(addr, size); diff --git a/arch/x86/lib/usercopy_64.c b/arch/x86/lib/usercopy_64.c index f42d2fd86ca3..75d3776123cc 100644 --- a/arch/x86/lib/usercopy_64.c +++ b/arch/x86/lib/usercopy_64.c @@ -97,6 +97,12 @@ static void clean_cache_range(void *addr, size_t size) clwb(p); } +void arch_wb_cache_pmem(void *addr, size_t size) +{ + clean_cache_range(addr, size); +} +EXPORT_SYMBOL_GPL(arch_wb_cache_pmem); + long __copy_user_flushcache(void *dst, const void __user *src, unsigned size) { unsigned long flushed, dest = (unsigned long) dst; diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 823b07774244..3b87702d46bb 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -245,7 +245,7 @@ static size_t pmem_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, static void pmem_dax_flush(struct dax_device *dax_dev, pgoff_t pgoff, void *addr, size_t size) { - wb_cache_pmem(addr, size); + arch_wb_cache_pmem(addr, size); } static const struct dax_operations pmem_dax_ops = { diff --git a/drivers/nvdimm/pmem.h b/drivers/nvdimm/pmem.h index 7f4dbd72a90a..c4b3371c7f88 100644 --- a/drivers/nvdimm/pmem.h +++ b/drivers/nvdimm/pmem.h @@ -5,6 +5,14 @@ #include #include +#ifdef CONFIG_ARCH_HAS_PMEM_API +void arch_wb_cache_pmem(void *addr, size_t size); +#else +static inline void arch_wb_cache_pmem(void *addr, size_t size) +{ +} +#endif + /* this definition is in it's own header for tools/testing/nvdimm to consume */ struct pmem_device { /* One contiguous memory region per device */ diff --git a/include/linux/pmem.h b/include/linux/pmem.h index 772bd02a5b52..33ae761f010a 100644 --- a/include/linux/pmem.h +++ b/include/linux/pmem.h @@ -31,11 +31,6 @@ static inline void arch_memcpy_to_pmem(void *dst, const void *src, size_t n) BUG(); } -static inline void arch_wb_cache_pmem(void *addr, size_t size) -{ - BUG(); -} - static inline void arch_invalidate_pmem(void *addr, size_t size) { BUG(); @@ -80,18 +75,4 @@ static inline void invalidate_pmem(void *addr, size_t size) if (arch_has_pmem_api()) arch_invalidate_pmem(addr, size); } - -/** - * wb_cache_pmem - write back processor cache for PMEM memory range - * @addr: virtual start address - * @size: number of bytes to write back - * - * Write back the processor cache range starting at 'addr' for 'size' bytes. - * See blkdev_issue_flush() note for memcpy_to_pmem(). - */ -static inline void wb_cache_pmem(void *addr, size_t size) -{ - if (arch_has_pmem_api()) - arch_wb_cache_pmem(addr, size); -} #endif /* __PMEM_H__ */