md/raid10: clear bad-block record when write succeeds.

If we succeed in writing to a block that was recorded as
being bad, we clear the bad-block record.

This requires some delayed handling as the bad-block-list update has
to happen in process-context.

Signed-off-by: NeilBrown <neilb@suse.de>

1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/md/raid10.h b/drivers/md/raid10.h
index c646152ba4e4..d8b7f9af92d5 100644
--- a/drivers/md/raid10.h
+++ b/drivers/md/raid10.h
@@ -118,6 +118,13 @@ struct r10bio_s {
  * level, we store IO_BLOCKED in the appropriate 'bios' pointer
  */
 #define IO_BLOCKED ((struct bio*)1)
+/* When we successfully write to a known bad-block, we need to remove the
+ * bad-block marking which must be done from process context.  So we record
+ * the success by setting devs[n].bio to IO_MADE_GOOD
+ */
+#define IO_MADE_GOOD ((struct bio *)2)
+
+#define BIO_SPECIAL(bio) ((unsigned long)bio <= 2)
 
 /* bits for r10bio.state */
 #define	R10BIO_Uptodate	0
@@ -128,4 +135,8 @@ struct r10bio_s {
  * so that raid10d knows what to do with them.
  */
 #define	R10BIO_ReadError 4
+/* If a write for this request means we can clear some
+ * known-bad-block records, we set this flag.
+ */
+#define	R10BIO_MadeGood 5
 #endif