Merge tag 'libnvdimm-fixes-5.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm fixes from Dan Williams:

 - Fix a regression that disabled device-mapper dax support

 - Remove unnecessary hardened-user-copy overhead (>30%) for dax
   read(2)/write(2).

 - Fix some compilation warnings.

* tag 'libnvdimm-fixes-5.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  libnvdimm/pmem: Bypass CONFIG_HARDENED_USERCOPY overhead
  dax: Arrange for dax_supported check to span multiple devices
  libnvdimm: Fix compilation warnings with W=1

1 files changed, 26 insertions, 0 deletions

diff --git a/include/linux/dax.h b/include/linux/dax.h
index 0dd316a74a29..becaea5f4488 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -19,6 +19,12 @@ struct dax_operations {
 	 */
 	long (*direct_access)(struct dax_device *, pgoff_t, long,
 			void **, pfn_t *);
+	/*
+	 * Validate whether this device is usable as an fsdax backing
+	 * device.
+	 */
+	bool (*dax_supported)(struct dax_device *, struct block_device *, int,
+			sector_t, sector_t);
 	/* copy_from_iter: required operation for fs-dax direct-i/o */
 	size_t (*copy_from_iter)(struct dax_device *, pgoff_t, void *, size_t,
 			struct iov_iter *);
@@ -75,6 +81,17 @@ static inline bool bdev_dax_supported(struct block_device *bdev, int blocksize)
 	return __bdev_dax_supported(bdev, blocksize);
 }
 
+bool __generic_fsdax_supported(struct dax_device *dax_dev,
+		struct block_device *bdev, int blocksize, sector_t start,
+		sector_t sectors);
+static inline bool generic_fsdax_supported(struct dax_device *dax_dev,
+		struct block_device *bdev, int blocksize, sector_t start,
+		sector_t sectors)
+{
+	return __generic_fsdax_supported(dax_dev, bdev, blocksize, start,
+			sectors);
+}
+
 static inline struct dax_device *fs_dax_get_by_host(const char *host)
 {
 	return dax_get_by_host(host);
@@ -99,6 +116,13 @@ static inline bool bdev_dax_supported(struct block_device *bdev,
 	return false;
 }
 
+static inline bool generic_fsdax_supported(struct dax_device *dax_dev,
+		struct block_device *bdev, int blocksize, sector_t start,
+		sector_t sectors)
+{
+	return false;
+}
+
 static inline struct dax_device *fs_dax_get_by_host(const char *host)
 {
 	return NULL;
@@ -142,6 +166,8 @@ bool dax_alive(struct dax_device *dax_dev);
 void *dax_get_private(struct dax_device *dax_dev);
 long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
 		void **kaddr, pfn_t *pfn);
+bool dax_supported(struct dax_device *dax_dev, struct block_device *bdev,
+		int blocksize, sector_t start, sector_t len);
 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,