Received-SPF: pass (google.com: domain of linux-kernel+bounces-204219-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.199.223 as permitted sender) client-ip=147.75.199.223;
From: Baolin Wang <baolin.wang@linux.alibaba.com>
To: akpm@linux-foundation.org,
	hughd@google.com
Cc: willy@infradead.org,
	david@redhat.com,
	wangkefeng.wang@huawei.com,
	chrisl@kernel.org,
	ying.huang@intel.com,
	21cnbao@gmail.com,
	ryan.roberts@arm.com,
	shy828301@gmail.com,
	ziy@nvidia.com,
	ioworker0@gmail.com,
	da.gomez@samsung.com,
	p.raghav@samsung.com,
	baolin.wang@linux.alibaba.com,
	linux-mm@kvack.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH 6/7] mm: shmem: use swap_free_nr() to free shmem swap entries
Date: Thu,  6 Jun 2024 19:58:56 +0800
Message-Id: <cd4095146729a2e548664c1174f07b263dbe17a4.1717673614.git.baolin.wang@linux.alibaba.com>
In-Reply-To: <cover.1717673614.git.baolin.wang@linux.alibaba.com>
References: <cover.1717673614.git.baolin.wang@linux.alibaba.com>
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit

As a preparation for supporting shmem large folio swapout, use swap_free_nr()
to free some continuous swap entries of the shmem large folio when the
large folio was swapped in from the swap cache.

Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
---
 mm/shmem.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/mm/shmem.c b/mm/shmem.c
index 28ba603d87b8..33af3b2e5ecf 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1950,6 +1950,7 @@ static void shmem_set_folio_swapin_error(struct inode *inode, pgoff_t index,
 	struct address_space *mapping = inode->i_mapping;
 	swp_entry_t swapin_error;
 	void *old;
+	int nr_pages;
 
 	swapin_error = make_poisoned_swp_entry();
 	old = xa_cmpxchg_irq(&mapping->i_pages, index,
@@ -1958,6 +1959,7 @@ static void shmem_set_folio_swapin_error(struct inode *inode, pgoff_t index,
 	if (old != swp_to_radix_entry(swap))
 		return;
 
+	nr_pages = folio_nr_pages(folio);
 	folio_wait_writeback(folio);
 	delete_from_swap_cache(folio);
 	/*
@@ -1965,8 +1967,8 @@ static void shmem_set_folio_swapin_error(struct inode *inode, pgoff_t index,
 	 * won't be 0 when inode is released and thus trigger WARN_ON(i_blocks)
 	 * in shmem_evict_inode().
 	 */
-	shmem_recalc_inode(inode, -1, -1);
-	swap_free(swap);
+	shmem_recalc_inode(inode, -nr_pages, -nr_pages);
+	swap_free_nr(swap, nr_pages);
 }
 
 /*
@@ -1985,7 +1987,7 @@ static int shmem_swapin_folio(struct inode *inode, pgoff_t index,
 	struct swap_info_struct *si;
 	struct folio *folio = NULL;
 	swp_entry_t swap;
-	int error;
+	int error, nr_pages;
 
 	VM_BUG_ON(!*foliop || !xa_is_value(*foliop));
 	swap = radix_to_swp_entry(*foliop);
@@ -2032,6 +2034,7 @@ static int shmem_swapin_folio(struct inode *inode, pgoff_t index,
 		goto failed;
 	}
 	folio_wait_writeback(folio);
+	nr_pages = folio_nr_pages(folio);
 
 	/*
 	 * Some architectures may have to restore extra metadata to the
@@ -2050,14 +2053,14 @@ static int shmem_swapin_folio(struct inode *inode, pgoff_t index,
 	if (error)
 		goto failed;
 
-	shmem_recalc_inode(inode, 0, -1);
+	shmem_recalc_inode(inode, 0, -nr_pages);
 
 	if (sgp == SGP_WRITE)
 		folio_mark_accessed(folio);
 
 	delete_from_swap_cache(folio);
 	folio_mark_dirty(folio);
-	swap_free(swap);
+	swap_free_nr(swap, nr_pages);
 	put_swap_device(si);
 
 	*foliop = folio;
-- 
2.39.3