1 files changed, 22 insertions, 17 deletions

diff --git a/mm/filemap.c b/mm/filemap.c
index ad8c39d90bf9..8f7ac3de9098 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -842,26 +842,27 @@ noinline int __filemap_add_folio(struct address_space *mapping,
 {
 	XA_STATE(xas, &mapping->i_pages, index);
 	int huge = folio_test_hugetlb(folio);
-	int error;
 	bool charged = false;
+	long nr = 1;
 
 	VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio);
 	VM_BUG_ON_FOLIO(folio_test_swapbacked(folio), folio);
 	mapping_set_update(&xas, mapping);
 
-	folio_get(folio);
-	folio->mapping = mapping;
-	folio->index = index;
-
 	if (!huge) {
-		error = mem_cgroup_charge(folio, NULL, gfp);
+		int error = mem_cgroup_charge(folio, NULL, gfp);
 		VM_BUG_ON_FOLIO(index & (folio_nr_pages(folio) - 1), folio);
 		if (error)
-			goto error;
+			return error;
 		charged = true;
+		xas_set_order(&xas, index, folio_order(folio));
+		nr = folio_nr_pages(folio);
 	}
 
 	gfp &= GFP_RECLAIM_MASK;
+	folio_ref_add(folio, nr);
+	folio->mapping = mapping;
+	folio->index = xas.xa_index;
 
 	do {
 		unsigned int order = xa_get_order(xas.xa, xas.xa_index);
@@ -885,6 +886,8 @@ noinline int __filemap_add_folio(struct address_space *mapping,
 			/* entry may have been split before we acquired lock */
 			order = xa_get_order(xas.xa, xas.xa_index);
 			if (order > folio_order(folio)) {
+				/* How to handle large swap entries? */
+				BUG_ON(shmem_mapping(mapping));
 				xas_split(&xas, old, order);
 				xas_reset(&xas);
 			}
@@ -894,29 +897,31 @@ noinline int __filemap_add_folio(struct address_space *mapping,
 		if (xas_error(&xas))
 			goto unlock;
 
-		mapping->nrpages++;
+		mapping->nrpages += nr;
 
 		/* hugetlb pages do not participate in page cache accounting */
-		if (!huge)
-			__lruvec_stat_add_folio(folio, NR_FILE_PAGES);
+		if (!huge) {
+			__lruvec_stat_mod_folio(folio, NR_FILE_PAGES, nr);
+			if (folio_test_pmd_mappable(folio))
+				__lruvec_stat_mod_folio(folio,
+						NR_FILE_THPS, nr);
+		}
 unlock:
 		xas_unlock_irq(&xas);
 	} while (xas_nomem(&xas, gfp));
 
-	if (xas_error(&xas)) {
-		error = xas_error(&xas);
-		if (charged)
-			mem_cgroup_uncharge(folio);
+	if (xas_error(&xas))
 		goto error;
-	}
 
 	trace_mm_filemap_add_to_page_cache(folio);
 	return 0;
 error:
+	if (charged)
+		mem_cgroup_uncharge(folio);
 	folio->mapping = NULL;
 	/* Leave page->index set: truncation relies upon it */
-	folio_put(folio);
-	return error;
+	folio_put_refs(folio, nr);
+	return xas_error(&xas);
 }
 ALLOW_ERROR_INJECTION(__filemap_add_folio, ERRNO);