[PATCH RFC 4/5] mm/gup-test: Verify exclusive pinned

Elliot Berman
2024-06-19T00:05:32Z

Add test that pages have the exclusive pin bias when providing
FOLL_EXCLUSIVE.

Signed-off-by: Elliot Berman <quic_eberman@quicinc.com>
---
mm/gup_test.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)

diff --git a/mm/gup_test.c b/mm/gup_test.c
index eeb3f4d87c510..9c6b8c93e44a7 100644
--- a/mm/gup_test.c
+++ b/mm/gup_test.c
@@ -66,6 +66,26 @@ static void verify_dma_pinned(unsigned int cmd, struct page **pages,
}
}

+static void verify_exclusive_pinned(unsigned int gup_flags, struct page **pages,
+ unsigned long nr_pages)
+{
+ unsigned long i;
+ const struct folio *folio;
+
+ if (!(gup_flags & FOLL_EXCLUSIVE))
+ return;
+
+ for (i = 0; i < nr_pages; i++) {
+ folio = page_folio(pages[i]);
+
+ if (WARN(!folio_maybe_exclusive_pinned(folio),
+ "pages[%lu] is not exclusive pinned\n", i)) {
+ dump_page(&folio->page, "gup_test failure");
+ break;
+ }
+ }
+}
+
static void dump_pages_test(struct gup_test *gup, struct page **pages,
unsigned long nr_pages)
{
@@ -185,6 +205,8 @@ static int __gup_test_ioctl(unsigned int cmd,
*/
verify_dma_pinned(cmd, pages, nr_pages);

+ verify_exclusive_pinned(gup->gup_flags, pages, nr_pages);
+
if (cmd == DUMP_USER_PAGES_TEST)
dump_pages_test(gup, pages, nr_pages);

--
2.34.1