md/raid456: When read error cannot be recovered, record bad block

We may not be able to fix a bad block if:
 - the array is degraded
 - the over-write fails.

In these cases we currently eject the device, but we should
record a bad block if possible.

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

1 files changed, 11 insertions, 4 deletions

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index a5135e595866..51169ecd7787 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -1743,6 +1743,7 @@ static void raid5_end_read_request(struct bio * bi, int error)
         } else {
                 const char *bdn = bdevname(rdev->bdev, b);
                 int retry = 0;
+                int set_bad = 0;
 
                 clear_bit(R5_UPTODATE, &sh->dev[i].flags);
                 atomic_inc(&rdev->read_errors);
@@ -1754,7 +1755,8 @@ static void raid5_end_read_request(struct bio * bi, int error)
                                 mdname(conf->mddev),
                                 (unsigned long long)s,
                                 bdn);
-                else if (conf->mddev->degraded >= conf->max_degraded)
+                else if (conf->mddev->degraded >= conf->max_degraded) {
+                        set_bad = 1;
                         printk_ratelimited(
                                 KERN_WARNING
                                 "md/raid:%s: read error not correctable "
@@ -1762,8 +1764,9 @@ static void raid5_end_read_request(struct bio * bi, int error)
                                 mdname(conf->mddev),
                                 (unsigned long long)s,
                                 bdn);
-                else if (test_bit(R5_ReWrite, &sh->dev[i].flags))
+                } else if (test_bit(R5_ReWrite, &sh->dev[i].flags)) {
                         /* Oh, no!!! */
+                        set_bad = 1;
                         printk_ratelimited(
                                 KERN_WARNING
                                 "md/raid:%s: read error NOT corrected!! "
@@ -1771,7 +1774,7 @@ static void raid5_end_read_request(struct bio * bi, int error)
                                 mdname(conf->mddev),
                                 (unsigned long long)s,
                                 bdn);
-                else if (atomic_read(&rdev->read_errors)
+                } else if (atomic_read(&rdev->read_errors)
                          > conf->max_nr_stripes)
                         printk(KERN_WARNING
                                "md/raid:%s: Too many read errors, failing device %s.\n",
@@ -1783,7 +1786,11 @@ static void raid5_end_read_request(struct bio * bi, int error)
                 else {
                         clear_bit(R5_ReadError, &sh->dev[i].flags);
                         clear_bit(R5_ReWrite, &sh->dev[i].flags);
-                        md_error(conf->mddev, rdev);
+                        if (!(set_bad
+                              && test_bit(In_sync, &rdev->flags)
+                              && rdev_set_badblocks(
+                                      rdev, sh->sector, STRIPE_SECTORS, 0)))
+                                md_error(conf->mddev, rdev);
                 }
         }
         rdev_dec_pending(rdev, conf->mddev);