libnvdimm, pmem: clear poison on write

If a write is directed at a known bad block perform the following:

1/ write the data

2/ send a clear poison command

3/ invalidate the poison out of the cache hierarchy

Cc: <x86@kernel.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/include/linux/pmem.h b/include/linux/pmem.h
index 7c3d11a6b4ad..3ec5309e29f3 100644
--- a/include/linux/pmem.h
+++ b/include/linux/pmem.h
@@ -58,6 +58,11 @@ static inline void arch_wb_cache_pmem(void __pmem *addr, size_t size)
 {
 	BUG();
 }
+
+static inline void arch_invalidate_pmem(void __pmem *addr, size_t size)
+{
+	BUG();
+}
 #endif
 
 /*
@@ -186,6 +191,20 @@ static inline void clear_pmem(void __pmem *addr, size_t size)
 }
 
 /**
+ * invalidate_pmem - flush a pmem range from the cache hierarchy
+ * @addr:	virtual start address
+ * @size:	bytes to invalidate (internally aligned to cache line size)
+ *
+ * For platforms that support clearing poison this flushes any poisoned
+ * ranges out of the cache
+ */
+static inline void invalidate_pmem(void __pmem *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