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From:   Sidhartha Kumar <sidhartha.kumar@oracle.com>
To:     linux-kernel@vger.kernel.org, linux-mm@kvack.org
Cc:     akpm@linux-foundation.org, willy@infradead.org,
        Sidhartha Kumar <sidhartha.kumar@oracle.com>
Subject: [PATCH v2 4/4] mm/memory: convert do_read_fault() to use folios
Date:   Wed,  5 Jul 2023 12:43:35 -0700
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Saves one implicit call to compound_head()

Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
---
v2
	 - move folio initialization after __do_fault()

 mm/memory.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/mm/memory.c b/mm/memory.c
index ce7826d3f6200..e40a03e488ca2 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4527,6 +4527,7 @@ static inline bool should_fault_around(struct vm_fault *vmf)
 static vm_fault_t do_read_fault(struct vm_fault *vmf)
 {
 	vm_fault_t ret = 0;
+	struct folio *folio;
 
 	/*
 	 * Let's call ->map_pages() first and use ->fault() as fallback
@@ -4543,10 +4544,12 @@ static vm_fault_t do_read_fault(struct vm_fault *vmf)
 	if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY)))
 		return ret;
 
+	folio = page_folio(vmf->page);
+
 	ret |= finish_fault(vmf);
-	unlock_page(vmf->page);
+	folio_unlock(folio);
 	if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY)))
-		put_page(vmf->page);
+		folio_put(folio);
 	return ret;
 }
 
-- 
2.41.0