Merge tag 'libnvdimm-for-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm and dax updates from Dan Williams:
 "There were multiple touches outside of drivers/nvdimm/ this round to
  add cross arch compatibility to the devm_memremap_pages() interface,
  enhance numa information for persistent memory ranges, and add a
  zero_page_range() dax operation.

  This cycle I switched from the patchwork api to Konstantin's b4 script
  for collecting tags (from x86, PowerPC, filesystem, and device-mapper
  folks), and everything looks to have gone ok there. This has all
  appeared in -next with no reported issues.

  Summary:

   - Add support for region alignment configuration and enforcement to
     fix compatibility across architectures and PowerPC page size
     configurations.

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

   - Introduce phys_to_target_node() to facilitate drivers that want to
     know resulting numa node if a given reserved address range was
     onlined.

   - 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.

   - Promote numa_map_to_online_node() to a cross-kernel generic
     facility.

   - Save x86 numa information to allow for node-id lookups for reserved
     memory ranges, deploy that capability for the e820-pmem driver.

   - Pick up some miscellaneous minor fixes, that missed v5.6-final,
     including a some smatch reports in the ioctl path and some unit
     test compilation fixups.

   - Fixup some flexible-array declarations"

* tag 'libnvdimm-for-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (29 commits)
  dax: Move mandatory ->zero_page_range() check in alloc_dax()
  dax,iomap: Add helper dax_iomap_zero() to zero a range
  dax: Use new dax zero page method for zeroing a page
  dm,dax: Add dax zero_page_range operation
  s390,dcssblk,dax: Add dax zero_page_range operation to dcssblk driver
  dax, pmem: Add a dax operation zero_page_range
  pmem: Add functions for reading/writing page to/from pmem
  libnvdimm: Update persistence domain value for of_pmem and papr_scm device
  tools/test/nvdimm: Fix out of tree build
  libnvdimm/region: Fix build error
  libnvdimm/region: Replace zero-length array with flexible-array member
  libnvdimm/label: Replace zero-length array with flexible-array member
  ACPI: NFIT: Replace zero-length array with flexible-array member
  libnvdimm/region: Introduce an 'align' attribute
  libnvdimm/region: Introduce NDD_LABELING
  libnvdimm/namespace: Enforce memremap_compat_align()
  libnvdimm/pfn: Prevent raw mode fallback if pfn-infoblock valid
  libnvdimm: Out of bounds read in __nd_ioctl()
  acpi/nfit: improve bounds checking for 'func'
  mm/memremap_pages: Introduce memremap_compat_align()
  ...

2 files changed, 27 insertions, 41 deletions

diff --git a/fs/dax.c b/fs/dax.c
index 35da144375a0..11b16729b86f 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -1038,50 +1038,43 @@ static vm_fault_t dax_load_hole(struct xa_state *xas,
 	return ret;
 }
 
-static bool dax_range_is_aligned(struct block_device *bdev,
-				 unsigned int offset, unsigned int length)
+int dax_iomap_zero(loff_t pos, unsigned offset, unsigned size,
+		   struct iomap *iomap)
 {
-	unsigned short sector_size = bdev_logical_block_size(bdev);
+	sector_t sector = iomap_sector(iomap, pos & PAGE_MASK);
+	pgoff_t pgoff;
+	long rc, id;
+	void *kaddr;
+	bool page_aligned = false;
 
-	if (!IS_ALIGNED(offset, sector_size))
-		return false;
-	if (!IS_ALIGNED(length, sector_size))
-		return false;
 
-	return true;
-}
+	if (IS_ALIGNED(sector << SECTOR_SHIFT, PAGE_SIZE) &&
+	    IS_ALIGNED(size, PAGE_SIZE))
+		page_aligned = true;
 
-int __dax_zero_page_range(struct block_device *bdev,
-		struct dax_device *dax_dev, sector_t sector,
-		unsigned int offset, unsigned int size)
-{
-	if (dax_range_is_aligned(bdev, offset, size)) {
-		sector_t start_sector = sector + (offset >> 9);
+	rc = bdev_dax_pgoff(iomap->bdev, sector, PAGE_SIZE, &pgoff);
+	if (rc)
+		return rc;
 
-		return blkdev_issue_zeroout(bdev, start_sector,
-				size >> 9, GFP_NOFS, 0);
-	} else {
-		pgoff_t pgoff;
-		long rc, id;
-		void *kaddr;
+	id = dax_read_lock();
 
-		rc = bdev_dax_pgoff(bdev, sector, PAGE_SIZE, &pgoff);
-		if (rc)
-			return rc;
+	if (page_aligned)
+		rc = dax_zero_page_range(iomap->dax_dev, pgoff,
+					 size >> PAGE_SHIFT);
+	else
+		rc = dax_direct_access(iomap->dax_dev, pgoff, 1, &kaddr, NULL);
+	if (rc < 0) {
+		dax_read_unlock(id);
+		return rc;
+	}
 
-		id = dax_read_lock();
-		rc = dax_direct_access(dax_dev, pgoff, 1, &kaddr, NULL);
-		if (rc < 0) {
-			dax_read_unlock(id);
-			return rc;
-		}
+	if (!page_aligned) {
 		memset(kaddr + offset, 0, size);
-		dax_flush(dax_dev, kaddr + offset, size);
-		dax_read_unlock(id);
+		dax_flush(iomap->dax_dev, kaddr + offset, size);
 	}
+	dax_read_unlock(id);
 	return 0;
 }
-EXPORT_SYMBOL_GPL(__dax_zero_page_range);
 
 static loff_t
 dax_iomap_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index f080f542911b..4da51a8ce324 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -975,13 +975,6 @@ static int iomap_zero(struct inode *inode, loff_t pos, unsigned offset,
 	return iomap_write_end(inode, pos, bytes, bytes, page, iomap, srcmap);
 }
 
-static int iomap_dax_zero(loff_t pos, unsigned offset, unsigned bytes,
-		struct iomap *iomap)
-{
-	return __dax_zero_page_range(iomap->bdev, iomap->dax_dev,
-			iomap_sector(iomap, pos & PAGE_MASK), offset, bytes);
-}
-
 static loff_t
 iomap_zero_range_actor(struct inode *inode, loff_t pos, loff_t count,
 		void *data, struct iomap *iomap, struct iomap *srcmap)
@@ -1001,7 +994,7 @@ iomap_zero_range_actor(struct inode *inode, loff_t pos, loff_t count,
 		bytes = min_t(loff_t, PAGE_SIZE - offset, count);
 
 		if (IS_DAX(inode))
-			status = iomap_dax_zero(pos, offset, bytes, iomap);
+			status = dax_iomap_zero(pos, offset, bytes, iomap);
 		else
 			status = iomap_zero(inode, pos, offset, bytes, iomap,
 					srcmap);