Commit 259e660d authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Alexander Gordeev
Browse files

s390/mm: Convert make_page_secure to use a folio 



These page APIs are deprecated, so convert the incoming page to a folio
and use the folio APIs instead.  The ultravisor API cannot handle large
folios, so return -EINVAL if one has slipped through.

Acked-by: default avatarClaudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lore.kernel.org/r/20240322161149.2327518-2-willy@infradead.org


Signed-off-by: default avatarAlexander Gordeev <agordeev@linux.ibm.com>
parent f10933cb

arch/s390/kernel/uv.c

+16 −13
Original line number Diff line number Diff line
@@ -182,21 +182,21 @@ int uv_convert_owned_from_secure(unsigned long paddr) 
}



/*

 * Calculate the expected ref_count for a page that would otherwise have no

 * Calculate the expected ref_count for a folio that would otherwise have no

 * further pins. This was cribbed from similar functions in other places in

 * the kernel, but with some slight modifications. We know that a secure

 * page can not be a huge page for example.

 * folio can not be a large folio, for example.

 */

static int expected_page_refs(struct page *page)

static int expected_folio_refs(struct folio *folio)

{

	int res;



	res = page_mapcount(page);

	if (PageSwapCache(page)) {

	res = folio_mapcount(folio);

	if (folio_test_swapcache(folio)) {

		res++;

	} else if (page_mapping(page)) {

	} else if (folio_mapping(folio)) {

		res++;

		if (page_has_private(page))

		if (folio->private)

			res++;

	}

	return res;
@@ -204,14 +204,17 @@ static int expected_page_refs(struct page *page) 


static int make_page_secure(struct page *page, struct uv_cb_header *uvcb)

{

	struct folio *folio = page_folio(page);

	int expected, cc = 0;



	if (PageWriteback(page))

	if (folio_test_large(folio))

		return -EINVAL;

	if (folio_test_writeback(folio))

		return -EAGAIN;

	expected = expected_page_refs(page);

	if (!page_ref_freeze(page, expected))

	expected = expected_folio_refs(folio);

	if (!folio_ref_freeze(folio, expected))

		return -EBUSY;

	set_bit(PG_arch_1, &page->flags);

	set_bit(PG_arch_1, &folio->flags);

	/*

	 * If the UVC does not succeed or fail immediately, we don't want to

	 * loop for long, or we might get stall notifications.
@@ -221,9 +224,9 @@ static int make_page_secure(struct page *page, struct uv_cb_header *uvcb) 
	 * -EAGAIN and we let the callers deal with it.

	 */

	cc = __uv_call(0, (u64)uvcb);

	page_ref_unfreeze(page, expected);

	folio_ref_unfreeze(folio, expected);

	/*

	 * Return -ENXIO if the page was not mapped, -EINVAL for other errors.

	 * Return -ENXIO if the folio was not mapped, -EINVAL for other errors.

	 * If busy or partially completed, return -EAGAIN.

	 */

	if (cc == UVC_CC_OK)