Merge tag 'libnvdimm-for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm from Dan Williams:
 "A rework of media error handling in the BTT driver and other updates.
  It has appeared in a few -next releases and collected some late-
  breaking build-error and warning fixups as a result.

  Summary:

   - Media error handling support in the Block Translation Table (BTT)
     driver is reworked to address sleeping-while-atomic locking and
     memory-allocation-context conflicts.

   - The dax_device lookup overhead for xfs and ext4 is moved out of the
     iomap hot-path to a mount-time lookup.

   - A new 'ecc_unit_size' sysfs attribute is added to advertise the
     read-modify-write boundary property of a persistent memory range.

   - Preparatory fix-ups for arm and powerpc pmem support are included
     along with other miscellaneous fixes"

* tag 'libnvdimm-for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (26 commits)
  libnvdimm, btt: fix format string warnings
  libnvdimm, btt: clean up warning and error messages
  ext4: fix null pointer dereference on sbi
  libnvdimm, nfit: move the check on nd_reserved2 to the endpoint
  dax: fix FS_DAX=n BLOCK=y compilation
  libnvdimm: fix integer overflow static analysis warning
  libnvdimm, nd_blk: remove mmio_flush_range()
  libnvdimm, btt: rework error clearing
  libnvdimm: fix potential deadlock while clearing errors
  libnvdimm, btt: cache sector_size in arena_info
  libnvdimm, btt: ensure that flags were also unchanged during a map_read
  libnvdimm, btt: refactor map entry operations with macros
  libnvdimm, btt: fix a missed NVDIMM_IO_ATOMIC case in the write path
  libnvdimm, nfit: export an 'ecc_unit_size' sysfs attribute
  ext4: perform dax_device lookup at mount
  ext2: perform dax_device lookup at mount
  xfs: perform dax_device lookup at mount
  dax: introduce a fs_dax_get_by_bdev() helper
  libnvdimm, btt: check memory allocation failure
  libnvdimm, label: fix index block size calculation
  ...

1 files changed, 12 insertions, 0 deletions

diff --git a/drivers/dax/super.c b/drivers/dax/super.c
index 938eb4868f7f..3600ff786646 100644
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c
@@ -46,6 +46,8 @@ void dax_read_unlock(int id)
 EXPORT_SYMBOL_GPL(dax_read_unlock);
 
 #ifdef CONFIG_BLOCK
+#include <linux/blkdev.h>
+
 int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size,
 		pgoff_t *pgoff)
 {
@@ -59,6 +61,16 @@ int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size,
 }
 EXPORT_SYMBOL(bdev_dax_pgoff);
 
+#if IS_ENABLED(CONFIG_FS_DAX)
+struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev)
+{
+	if (!blk_queue_dax(bdev->bd_queue))
+		return NULL;
+	return fs_dax_get_by_host(bdev->bd_disk->disk_name);
+}
+EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev);
+#endif
+
 /**
  * __bdev_dax_supported() - Check if the device supports dax for filesystem
  * @sb: The superblock of the device