[PATCH rfc 9/9] fs: aio: add explicit check for large folio in aio_migrate_folio()

[Kefeng Wang <wangkefeng.wang@huawei.com>]

Since large folio copy could spend lots of time and it is involved with
a cond_resched(), the aio couldn't support migrate large folio as it takes
a spin lock when folio copy, add explicit check for large folio and return
err directly.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
 fs/aio.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/fs/aio.c b/fs/aio.c
index 631e83eee5a1..372f22b85b11 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -411,6 +411,10 @@ static int aio_migrate_folio(struct address_space *mapping, struct folio *dst,
 	pgoff_t idx;
 	int rc = 0;
 
+	/* Large folio aren't supported */
+	if (folio_test_large(src))
+		return -EINVAL;
+
 	/* mapping->i_private_lock here protects against the kioctx teardown.  */
 	spin_lock(&mapping->i_private_lock);
 	ctx = mapping->i_private_data;
-- 
2.27.0