diff options
| -rw-r--r-- | drivers/nvdimm/pmem.c | 14 | ||||
| -rw-r--r-- | include/linux/pmem.h | 22 |
2 files changed, 30 insertions, 6 deletions
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 8e09c544d892..f798899338ed 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -103,6 +103,20 @@ static int pmem_do_bvec(struct pmem_device *pmem, struct page *page, flush_dcache_page(page); } } else { + /* + * Note that we write the data both before and after + * clearing poison. The write before clear poison + * handles situations where the latest written data is + * preserved and the clear poison operation simply marks + * the address range as valid without changing the data. + * In this case application software can assume that an + * interrupted write will either return the new good + * data or an error. + * + * However, if pmem_clear_poison() leaves the data in an + * indeterminate state we need to perform the write + * after clear poison. + */ flush_dcache_page(page); memcpy_to_pmem(pmem_addr, mem + off, len); if (unlikely(bad_pmem)) { diff --git a/include/linux/pmem.h b/include/linux/pmem.h index ac6d872ce067..57d146fe44dd 100644 --- a/include/linux/pmem.h +++ b/include/linux/pmem.h @@ -72,6 +72,18 @@ static inline void arch_invalidate_pmem(void __pmem *addr, size_t size) } #endif +static inline bool arch_has_pmem_api(void) +{ + return IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API); +} + +static inline int default_memcpy_from_pmem(void *dst, void __pmem const *src, + size_t size) +{ + memcpy(dst, (void __force *) src, size); + return 0; +} + /* * memcpy_from_pmem - read from persistent memory with error handling * @dst: destination buffer @@ -83,12 +95,10 @@ static inline void arch_invalidate_pmem(void __pmem *addr, size_t size) static inline int memcpy_from_pmem(void *dst, void __pmem const *src, size_t size) { - return arch_memcpy_from_pmem(dst, src, size); -} - -static inline bool arch_has_pmem_api(void) -{ - return IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API); + if (arch_has_pmem_api()) + return arch_memcpy_from_pmem(dst, src, size); + else + return default_memcpy_from_pmem(dst, src, size); } /** |