[PATCH v6 14/16] mm: zswap: Introduce zswap_compress_folio() to compress all pages in a folio.

[Kanchana P Sridhar]

This patch encapsulates away the computes for compressing the pages in a
folio and storing the compressed memory in zpool, into a distinct
zswap_compress_folio() procedure.

For now, zswap_compress_folio() simply calls zswap_compress() for each page
in the folio it is called with.

This facilitates adding compress batching in subsequent patches.

Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@xxxxxxxxx>
---
 mm/zswap.c | 24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/mm/zswap.c b/mm/zswap.c
index af682bf0f690..6563d12e907b 100644
--- a/mm/zswap.c
+++ b/mm/zswap.c
@@ -1509,6 +1509,22 @@ static void shrink_worker(struct work_struct *w)
 * main API
 **********************************/
 
+static bool zswap_compress_folio(struct folio *folio,
+				 struct zswap_entry *entries[],
+				 struct zswap_pool *pool)
+{
+	long index, nr_pages = folio_nr_pages(folio);
+
+	for (index = 0; index < nr_pages; ++index) {
+		struct page *page = folio_page(folio, index);
+
+		if (!zswap_compress(page, entries[index], pool))
+			return false;
+	}
+
+	return true;
+}
+
 /*
  * Store all pages in a folio.
  *
@@ -1542,12 +1558,8 @@ static bool zswap_store_folio(struct folio *folio,
 		entries[index]->handle = (unsigned long)ERR_PTR(-EINVAL);
 	}
 
-	for (index = 0; index < nr_pages; ++index) {
-		struct page *page = folio_page(folio, index);
-
-		if (!zswap_compress(page, entries[index], pool))
-			goto store_folio_failed;
-	}
+	if (!zswap_compress_folio(folio, entries, pool))
+		goto store_folio_failed;
 
 	for (index = 0; index < nr_pages; ++index) {
 		swp_entry_t page_swpentry = page_swap_entry(folio_page(folio, index));
-- 
2.27.0