[PATCH v7 06/22] mm: clear AS_EIO/AS_ENOSPC when writeback initiation fails

[Jeff Layton <jlayton@redhat.com>]

filemap_write_and_wait{_range} will return an error if writeback
initiation fails, but won't clear errors in the address_space. This is
particularly problematic on DAX, as it's effectively synchronous. Ensure
that we clear the AS_EIO/AS_ENOSPC flags when filemap_fdatawrite returns
an error.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
---
 mm/filemap.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/mm/filemap.c b/mm/filemap.c
index 37f286df7c95..c349a5d3a34b 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -517,6 +517,9 @@ int filemap_write_and_wait(struct address_space *mapping)
 			int err2 = filemap_fdatawait(mapping);
 			if (!err)
 				err = err2;
+		} else {
+			/* Clear any previously stored errors */
+			filemap_check_errors(mapping);
 		}
 	} else {
 		err = filemap_check_errors(mapping);
@@ -551,6 +554,9 @@ int filemap_write_and_wait_range(struct address_space *mapping,
 						lstart, lend);
 			if (!err)
 				err = err2;
+		} else {
+			/* Clear any previously stored errors */
+			filemap_check_errors(mapping);
 		}
 	} else {
 		err = filemap_check_errors(mapping);
-- 
2.13.0