[PATCH -next 2/2] nfs: nfs_file_write() check writeback errors correctly

[ChenXiaoSong <chenxiaosong2@huawei.com>]

If nobody has seen the writeback error yet, then filemap_sample_wb_err()
always return 0. Even if there is no new writeback error between
filemap_sample_wb_err() and filemap_check_wb_err(),
filemap_check_wb_err() will return the old error.

Fix this by using file->f_mapping->wb_err as the old error.

Fixes: ce368536dd61 ("nfs: nfs_file_write() should check for writeback errors")
Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com>
---
 fs/nfs/file.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 83d63bce9596..8763f89c176a 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -635,7 +635,7 @@ ssize_t nfs_file_write(struct kiocb *iocb, struct iov_iter *from)
 
 	nfs_clear_invalid_mapping(file->f_mapping);
 
-	since = filemap_sample_wb_err(file->f_mapping);
+	since = file->f_mapping->wb_err;
 	nfs_start_io_write(inode);
 	result = generic_write_checks(iocb, from);
 	if (result > 0) {
@@ -669,7 +669,7 @@ ssize_t nfs_file_write(struct kiocb *iocb, struct iov_iter *from)
 		goto out;
 
 	/* Return error values */
-	error = filemap_check_wb_err(file->f_mapping, since);
+	error = errseq_check(&file->f_mapping->wb_err, since);
 	if (nfs_need_check_write(file, inode, error)) {
 		int err = nfs_wb_all(inode);
 		if (err < 0)
-- 
2.31.1