Unverified Commit 80fce305 authored by Brian Foster's avatar Brian Foster Committed by Christian Brauner
Browse files

dax: advance the iomap_iter on zero range 



Update the DAX zero range iomap iter handler to advance the iter
directly. Advance by the full length in the hole/unwritten case, or
otherwise advance incrementally in the zeroing loop. In either case,
return 0 or an error code for success or failure.

Signed-off-by: default avatarBrian Foster <bfoster@redhat.com>
Link: https://lore.kernel.org/r/20250224144757.237706-7-bfoster@redhat.com


Reviewed-by: default avatar"Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent e1dae77b

fs/dax.c

+17 −16
Original line number Diff line number Diff line
@@ -1358,13 +1358,12 @@ static s64 dax_zero_iter(struct iomap_iter *iter, bool *did_zero) 
{

	const struct iomap *iomap = &iter->iomap;

	const struct iomap *srcmap = iomap_iter_srcmap(iter);

	loff_t pos = iter->pos;

	u64 length = iomap_length(iter);

	s64 written = 0;

	s64 ret;



	/* already zeroed?  we're done. */

	if (srcmap->type == IOMAP_HOLE || srcmap->type == IOMAP_UNWRITTEN)

		return length;

		return iomap_iter_advance(iter, &length);



	/*

	 * invalidate the pages whose sharing state is to be changed
@@ -1372,33 +1371,35 @@ static s64 dax_zero_iter(struct iomap_iter *iter, bool *did_zero) 
	 */

	if (iomap->flags & IOMAP_F_SHARED)

		invalidate_inode_pages2_range(iter->inode->i_mapping,

					      pos >> PAGE_SHIFT,

					      (pos + length - 1) >> PAGE_SHIFT);

				iter->pos >> PAGE_SHIFT,

				(iter->pos + length - 1) >> PAGE_SHIFT);



	do {

		loff_t pos = iter->pos;

		unsigned offset = offset_in_page(pos);

		unsigned size = min_t(u64, PAGE_SIZE - offset, length);

		pgoff_t pgoff = dax_iomap_pgoff(iomap, pos);

		long rc;

		int id;



		length = min_t(u64, PAGE_SIZE - offset, length);



		id = dax_read_lock();

		if (IS_ALIGNED(pos, PAGE_SIZE) && size == PAGE_SIZE)

			rc = dax_zero_page_range(iomap->dax_dev, pgoff, 1);

		if (IS_ALIGNED(pos, PAGE_SIZE) && length == PAGE_SIZE)

			ret = dax_zero_page_range(iomap->dax_dev, pgoff, 1);

		else

			rc = dax_memzero(iter, pos, size);

			ret = dax_memzero(iter, pos, length);

		dax_read_unlock(id);



		if (rc < 0)

			return rc;

		pos += size;

		length -= size;

		written += size;

		if (ret < 0)

			return ret;



		ret = iomap_iter_advance(iter, &length);

		if (ret)

			return ret;

	} while (length > 0);



	if (did_zero)

		*did_zero = true;

	return written;

	return ret;

}



int dax_zero_range(struct inode *inode, loff_t pos, loff_t len, bool *did_zero,