1 files changed, 27 insertions, 2 deletions
diff --git a/mm/mincore.c b/mm/mincore.c
index 10dabefc3acc..20fd0967d3cb 100644
--- a/mm/mincore.c
+++ b/mm/mincore.c
@@ -64,8 +64,33 @@ static unsigned char mincore_page(struct address_space *mapping, pgoff_t index)
 	 * any other file mapping (ie. marked !present and faulted in with
 	 * tmpfs's .fault). So swapped out tmpfs mappings are tested here.
 	 */
-	folio = filemap_get_incore_folio(mapping, index);
-	if (!IS_ERR(folio)) {
+	if (IS_ENABLED(CONFIG_SWAP) && shmem_mapping(mapping)) {
+		folio = filemap_get_entry(mapping, index);
+		/*
+		 * shmem/tmpfs may return swap: account for swapcache
+		 * page too.
+		 */
+		if (xa_is_value(folio)) {
+			struct swap_info_struct *si;
+			swp_entry_t swp = radix_to_swp_entry(folio);
+			/* There might be swapin error entries in shmem mapping. */
+			if (non_swap_entry(swp))
+				return 0;
+			/* Prevent swap device to being swapoff under us */
+			si = get_swap_device(swp);
+			if (si) {
+				folio = filemap_get_folio(swap_address_space(swp),
+							  swap_cache_index(swp));
+				put_swap_device(si);
+			} else {
+				return 0;
+			}
+		}
+	} else {
+		folio = filemap_get_folio(mapping, index);
+	}
+
+	if (!IS_ERR_OR_NULL(folio)) {
 		present = folio_test_uptodate(folio);
 		folio_put(folio);
 	}