Commit 8dbfc76d authored by Shiyang Ruan's avatar Shiyang Ruan Committed by Andrew Morton
Browse files

fsdax: add dax_iomap_cow_copy() for dax zero 

Punch hole on a reflinked file needs dax_iomap_cow_copy() too.  Otherwise,
data in not aligned area will be not correct.  So, add the CoW operation
for not aligned case in dax_memzero().

Link: https://lkml.kernel.org/r/20220603053738.1218681-12-ruansy.fnst@fujitsu.com


Signed-off-by: default avatarShiyang Ruan <ruansy.fnst@fujitsu.com>
Reviewed-by: default avatarRitesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: default avatarDarrick J. Wong <djwong@kernel.org>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dan Williams <dan.j.wiliams@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.com>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.de>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent e5d6df73

fs/dax.c

+19 −8
Original line number Diff line number Diff line
@@ -1221,17 +1221,28 @@ static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf, 
}

#endif /* CONFIG_FS_DAX_PMD */



static int dax_memzero(struct dax_device *dax_dev, pgoff_t pgoff,

		unsigned int offset, size_t size)

static int dax_memzero(struct iomap_iter *iter, loff_t pos, size_t size)

{

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

	const struct iomap *srcmap = iomap_iter_srcmap(iter);

	unsigned offset = offset_in_page(pos);

	pgoff_t pgoff = dax_iomap_pgoff(iomap, pos);

	void *kaddr;

	long ret;



	ret = dax_direct_access(dax_dev, pgoff, 1, DAX_ACCESS, &kaddr, NULL);

	if (ret > 0) {

	ret = dax_direct_access(iomap->dax_dev, pgoff, 1, DAX_ACCESS, &kaddr,

				NULL);

	if (ret < 0)

		return ret;

	memset(kaddr + offset, 0, size);

		dax_flush(dax_dev, kaddr + offset, size);

	}

	if (srcmap->addr != iomap->addr) {

		ret = dax_iomap_cow_copy(pos, size, PAGE_SIZE, srcmap,

					 kaddr);

		if (ret < 0)

			return ret;

		dax_flush(iomap->dax_dev, kaddr, PAGE_SIZE);

	} else

		dax_flush(iomap->dax_dev, kaddr + offset, size);

	return ret;

}
@@ -1258,7 +1269,7 @@ static s64 dax_zero_iter(struct iomap_iter *iter, bool *did_zero) 
		if (IS_ALIGNED(pos, PAGE_SIZE) && size == PAGE_SIZE)

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

		else

			rc = dax_memzero(iomap->dax_dev, pgoff, offset, size);

			rc = dax_memzero(iter, pos, size);

		dax_read_unlock(id);



		if (rc < 0)