Merge branch 'for-5.7/libnvdimm' into libnvdimm-for-next

- Introduce 'zero_page_range' as a dax operation. This facilitates
  filesystem-dax operation without a block-device.

- Advertise a persistence-domain for of_pmem and papr_scm. The
  persistence domain indicates where cpu-store cycles need to reach in
  the platform-memory subsystem before the platform will consider them
  power-fail protected.

- Fixup some flexible-array declarations.

2 files changed, 10 insertions, 14 deletions

diff --git a/include/linux/dax.h b/include/linux/dax.h
index 328c2dbb4409..d7af5d243f24 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -13,6 +13,7 @@
 typedef unsigned long dax_entry_t;
 
 struct iomap_ops;
+struct iomap;
 struct dax_device;
 struct dax_operations {
 	/*
@@ -34,6 +35,8 @@ struct dax_operations {
 	/* copy_to_iter: required operation for fs-dax direct-i/o */
 	size_t (*copy_to_iter)(struct dax_device *, pgoff_t, void *, size_t,
 			struct iov_iter *);
+	/* zero_page_range: required operation. Zero page range   */
+	int (*zero_page_range)(struct dax_device *, pgoff_t, size_t);
 };
 
 extern struct attribute_group dax_attribute_group;
@@ -199,6 +202,8 @@ size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
 		size_t bytes, struct iov_iter *i);
 size_t dax_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
 		size_t bytes, struct iov_iter *i);
+int dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
+			size_t nr_pages);
 void dax_flush(struct dax_device *dax_dev, void *addr, size_t size);
 
 ssize_t dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter,
@@ -210,20 +215,8 @@ vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf,
 int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index);
 int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
 				      pgoff_t index);
-
-#ifdef CONFIG_FS_DAX
-int __dax_zero_page_range(struct block_device *bdev,
-		struct dax_device *dax_dev, sector_t sector,
-		unsigned int offset, unsigned int length);
-#else
-static inline int __dax_zero_page_range(struct block_device *bdev,
-		struct dax_device *dax_dev, sector_t sector,
-		unsigned int offset, unsigned int length)
-{
-	return -ENXIO;
-}
-#endif
-
+int dax_iomap_zero(loff_t pos, unsigned offset, unsigned size,
+			struct iomap *iomap);
 static inline bool dax_mapping(struct address_space *mapping)
 {
 	return mapping->host && IS_DAX(mapping->host);
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 475668c69dbc..af48d9da3916 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -141,6 +141,8 @@ typedef long (*dm_dax_direct_access_fn) (struct dm_target *ti, pgoff_t pgoff,
 		long nr_pages, void **kaddr, pfn_t *pfn);
 typedef size_t (*dm_dax_copy_iter_fn)(struct dm_target *ti, pgoff_t pgoff,
 		void *addr, size_t bytes, struct iov_iter *i);
+typedef int (*dm_dax_zero_page_range_fn)(struct dm_target *ti, pgoff_t pgoff,
+		size_t nr_pages);
 #define PAGE_SECTORS (PAGE_SIZE / 512)
 
 void dm_error(const char *message);
@@ -195,6 +197,7 @@ struct target_type {
 	dm_dax_direct_access_fn direct_access;
 	dm_dax_copy_iter_fn dax_copy_from_iter;
 	dm_dax_copy_iter_fn dax_copy_to_iter;
+	dm_dax_zero_page_range_fn dax_zero_page_range;
 
 	/* For internal device-mapper use. */
 	struct list_head list;