[PATCH v2 06/21] buffer: discard BH_Write_EIO along with the rest of the buffer state

[Chao Shi <coshi036@gmail.com>]

discard_buffer() strips the state that describes where a buffer lives and
what has happened to it, because after an invalidate none of it applies any
more.  BH_Write_EIO belongs in that set for the same reason: it describes a
write of the data that is being thrown away.

Leaving it set means a buffer_head reused for a different block starts life
carrying somebody else's write error.  Like the bforget() change, this is
mostly theoretical today and becomes load bearing once the rest of the
series makes BH_Write_EIO the report of a failed metadata write.

Suggested-by: Jan Kara <jack@suse.cz>
Acked-by: Weidong Zhu <weizhu@fiu.edu>
Signed-off-by: Chao Shi <coshi036@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
---
 fs/buffer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/buffer.c b/fs/buffer.c
index 381690479520..570ce7f495d3 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -1518,7 +1518,7 @@ EXPORT_SYMBOL(folio_set_bh);
 /* Bits that are cleared during an invalidate */
 #define BUFFER_FLAGS_DISCARD \
 	(1 << BH_Mapped | 1 << BH_New | 1 << BH_Req | \
-	 1 << BH_Delay | 1 << BH_Unwritten)
+	 1 << BH_Delay | 1 << BH_Unwritten | 1 << BH_Write_EIO)
 
 static void discard_buffer(struct buffer_head * bh)
 {
-- 
2.43.0