Commit d19bd675 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Dan Williams
Browse files

dm-log-writes: add a log_writes_dax_pgoff helper 



Add a helper to perform the entire remapping for DAX accesses.  This
helper open codes bdev_dax_pgoff given that the alignment checks have
already been done by the submitting file system and don't need to be
repeated.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Acked-by: default avatarMike Snitzer <snitzer@redhat.com>
Reviewed-by: default avatarDan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/20211129102203.2243509-11-hch@lst.de


Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent f43e0065

drivers/md/dm-log-writes.c

+17 −25
Original line number Diff line number Diff line
@@ -947,17 +947,21 @@ static int log_dax(struct log_writes_c *lc, sector_t sector, size_t bytes, 
	return 0;

}



static struct dax_device *log_writes_dax_pgoff(struct dm_target *ti,

		pgoff_t *pgoff)

{

	struct log_writes_c *lc = ti->private;



	*pgoff += (get_start_sect(lc->dev->bdev) >> PAGE_SECTORS_SHIFT);

	return lc->dev->dax_dev;

}



static long log_writes_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,

					 long nr_pages, void **kaddr, pfn_t *pfn)

{

	struct log_writes_c *lc = ti->private;

	sector_t sector = pgoff * PAGE_SECTORS;

	int ret;

	struct dax_device *dax_dev = log_writes_dax_pgoff(ti, &pgoff);



	ret = bdev_dax_pgoff(lc->dev->bdev, sector, nr_pages * PAGE_SIZE, &pgoff);

	if (ret)

		return ret;

	return dax_direct_access(lc->dev->dax_dev, pgoff, nr_pages, kaddr, pfn);

	return dax_direct_access(dax_dev, pgoff, nr_pages, kaddr, pfn);

}



static size_t log_writes_dax_copy_from_iter(struct dm_target *ti,
@@ -966,11 +970,9 @@ static size_t log_writes_dax_copy_from_iter(struct dm_target *ti, 
{

	struct log_writes_c *lc = ti->private;

	sector_t sector = pgoff * PAGE_SECTORS;

	struct dax_device *dax_dev = log_writes_dax_pgoff(ti, &pgoff);

	int err;



	if (bdev_dax_pgoff(lc->dev->bdev, sector, ALIGN(bytes, PAGE_SIZE), &pgoff))

		return 0;



	/* Don't bother doing anything if logging has been disabled */

	if (!lc->logging_enabled)

		goto dax_copy;
@@ -981,34 +983,24 @@ static size_t log_writes_dax_copy_from_iter(struct dm_target *ti, 
		return 0;

	}

dax_copy:

	return dax_copy_from_iter(lc->dev->dax_dev, pgoff, addr, bytes, i);

	return dax_copy_from_iter(dax_dev, pgoff, addr, bytes, i);

}



static size_t log_writes_dax_copy_to_iter(struct dm_target *ti,

					  pgoff_t pgoff, void *addr, size_t bytes,

					  struct iov_iter *i)

{

	struct log_writes_c *lc = ti->private;

	sector_t sector = pgoff * PAGE_SECTORS;

	struct dax_device *dax_dev = log_writes_dax_pgoff(ti, &pgoff);



	if (bdev_dax_pgoff(lc->dev->bdev, sector, ALIGN(bytes, PAGE_SIZE), &pgoff))

		return 0;

	return dax_copy_to_iter(lc->dev->dax_dev, pgoff, addr, bytes, i);

	return dax_copy_to_iter(dax_dev, pgoff, addr, bytes, i);

}



static int log_writes_dax_zero_page_range(struct dm_target *ti, pgoff_t pgoff,

					  size_t nr_pages)

{

	int ret;

	struct log_writes_c *lc = ti->private;

	sector_t sector = pgoff * PAGE_SECTORS;

	struct dax_device *dax_dev = log_writes_dax_pgoff(ti, &pgoff);



	ret = bdev_dax_pgoff(lc->dev->bdev, sector, nr_pages << PAGE_SHIFT,

			     &pgoff);

	if (ret)

		return ret;

	return dax_zero_page_range(lc->dev->dax_dev, pgoff,

				   nr_pages << PAGE_SHIFT);

	return dax_zero_page_range(dax_dev, pgoff, nr_pages << PAGE_SHIFT);

}



#else