Merge branch 'libnvdimm-for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm fixes from Dan Williams:
 "A couple of compile fixes.

  With the removal of the ->direct_access() method from
  block_device_operations in favor of a new dax_device + dax_operations
  we broke two configurations.

  The CONFIG_BLOCK=n case is fixed by compiling out the block+dax
  helpers in the dax core. Configurations with FS_DAX=n EXT4=y / XFS=y
  and DAX=m fail due to the helpers the builtin filesystem needs being
  in a module, so we stub out the helpers in the FS_DAX=n case."

* 'libnvdimm-for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  dax, xfs, ext4: compile out iomap-dax paths in the FS_DAX=n case
  dax: fix false CONFIG_BLOCK dependency

drivers/dax/super.c

@@ -44,6 +44,7 @@ void dax_read_unlock(int id)
 }
 EXPORT_SYMBOL_GPL(dax_read_unlock);
 
+#ifdef CONFIG_BLOCK
 int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size,
 		pgoff_t *pgoff)
 {
@@ -112,6 +113,7 @@ int __bdev_dax_supported(struct super_block *sb, int blocksize)
 	return 0;
 }
 EXPORT_SYMBOL_GPL(__bdev_dax_supported);
+#endif
 
 /**
  * struct dax_device - anchor object for dax services

fs/ext2/inode.c

@@ -817,7 +817,7 @@ static int ext2_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
 	iomap->bdev = bdev;
 	iomap->offset = (u64)first_block << blkbits;
 	if (blk_queue_dax(bdev->bd_queue))
-		iomap->dax_dev = dax_get_by_host(bdev->bd_disk->disk_name);
+		iomap->dax_dev = fs_dax_get_by_host(bdev->bd_disk->disk_name);
 	else
 		iomap->dax_dev = NULL;
 
@@ -841,7 +841,7 @@ static int
 ext2_iomap_end(struct inode *inode, loff_t offset, loff_t length,
 		ssize_t written, unsigned flags, struct iomap *iomap)
 {
-	put_dax(iomap->dax_dev);
+	fs_put_dax(iomap->dax_dev);
 	if (iomap->type == IOMAP_MAPPED &&
 	    written < length &&
 	    (flags & IOMAP_WRITE))

fs/ext4/inode.c

@@ -3412,7 +3412,7 @@ retry:
 	bdev = inode->i_sb->s_bdev;
 	iomap->bdev = bdev;
 	if (blk_queue_dax(bdev->bd_queue))
-		iomap->dax_dev = dax_get_by_host(bdev->bd_disk->disk_name);
+		iomap->dax_dev = fs_dax_get_by_host(bdev->bd_disk->disk_name);
 	else
 		iomap->dax_dev = NULL;
 	iomap->offset = first_block << blkbits;
@@ -3447,7 +3447,7 @@ static int ext4_iomap_end(struct inode *inode, loff_t offset, loff_t length,
 	int blkbits = inode->i_blkbits;
 	bool truncate = false;
 
-	put_dax(iomap->dax_dev);
+	fs_put_dax(iomap->dax_dev);
 	if (!(flags & IOMAP_WRITE) || (flags & IOMAP_FAULT))
 		return 0;
 

fs/xfs/xfs_iomap.c

@@ -1068,7 +1068,7 @@ xfs_file_iomap_begin(
 	/* optionally associate a dax device with the iomap bdev */
 	bdev = iomap->bdev;
 	if (blk_queue_dax(bdev->bd_queue))
-		iomap->dax_dev = dax_get_by_host(bdev->bd_disk->disk_name);
+		iomap->dax_dev = fs_dax_get_by_host(bdev->bd_disk->disk_name);
 	else
 		iomap->dax_dev = NULL;
 
@@ -1149,7 +1149,7 @@ xfs_file_iomap_end(
 	unsigned		flags,
 	struct iomap		*iomap)
 {
-	put_dax(iomap->dax_dev);
+	fs_put_dax(iomap->dax_dev);
 	if ((flags & IOMAP_WRITE) && iomap->type == IOMAP_DELALLOC)
 		return xfs_file_iomap_end_delalloc(XFS_I(inode), offset,
 				length, written, iomap);

include/linux/dax.h

@@ -18,6 +18,20 @@ struct dax_operations {
 			void **, pfn_t *);
 };
 
+#if IS_ENABLED(CONFIG_DAX)
+struct dax_device *dax_get_by_host(const char *host);
+void put_dax(struct dax_device *dax_dev);
+#else
+static inline struct dax_device *dax_get_by_host(const char *host)
+{
+	return NULL;
+}
+
+static inline void put_dax(struct dax_device *dax_dev)
+{
+}
+#endif
+
 int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff);
 #if IS_ENABLED(CONFIG_FS_DAX)
 int __bdev_dax_supported(struct super_block *sb, int blocksize);
@@ -25,23 +39,29 @@ static inline int bdev_dax_supported(struct super_block *sb, int blocksize)
 {
 	return __bdev_dax_supported(sb, blocksize);
 }
+
+static inline struct dax_device *fs_dax_get_by_host(const char *host)
+{
+	return dax_get_by_host(host);
+}
+
+static inline void fs_put_dax(struct dax_device *dax_dev)
+{
+	put_dax(dax_dev);
+}
+
 #else
 static inline int bdev_dax_supported(struct super_block *sb, int blocksize)
 {
 	return -EOPNOTSUPP;
 }
-#endif
 
-#if IS_ENABLED(CONFIG_DAX)
-struct dax_device *dax_get_by_host(const char *host);
-void put_dax(struct dax_device *dax_dev);
-#else
-static inline struct dax_device *dax_get_by_host(const char *host)
+static inline struct dax_device *fs_dax_get_by_host(const char *host)
 {
 	return NULL;
 }
 
-static inline void put_dax(struct dax_device *dax_dev)
+static inline void fs_put_dax(struct dax_device *dax_dev)
 {
 }
 #endif