[PATCH] md: include sector number in messages about corrected read errors

This is generally useful, but particularly helps see if it is the same sector
that always needs correcting, or different ones.

[akpm@osdl.org: fix printk warnings]
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/md/raid1.c

@@ -1509,6 +1509,9 @@ static void raid1d(mddev_t *mddev)
 									 s<<9, conf->tmppage, READ) == 0)
 								/* Well, this device is dead */
 								md_error(mddev, rdev);
+							else
+								printk(KERN_INFO "raid1:%s: read error corrected (%d sectors at %llu on %s)\n",
+								       mdname(mddev), s, (unsigned long long)(sect + rdev->data_offset), bdevname(rdev->bdev, b));
 						}
 					}
 				} else {

drivers/md/raid10.c

@@ -1492,6 +1492,10 @@ static void raid10d(mddev_t *mddev)
 									 s<<9, conf->tmppage, READ) == 0)
 								/* Well, this device is dead */
 								md_error(mddev, rdev);
+							else
+								printk(KERN_INFO "raid10:%s: read error corrected (%d sectors at %llu on %s)\n",
+								       mdname(mddev), s, (unsigned long long)(sect+rdev->data_offset), bdevname(rdev->bdev, b));
+
 							rdev_dec_pending(rdev, mddev);
 							rcu_read_lock();
 						}

drivers/md/raid5.c

@@ -523,6 +523,8 @@ static int raid5_end_read_request(struct bio * bi, unsigned int bytes_done,
 	raid5_conf_t *conf = sh->raid_conf;
 	int disks = sh->disks, i;
 	int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags);
+	char b[BDEVNAME_SIZE];
+	mdk_rdev_t *rdev;
 
 	if (bi->bi_size)
 		return 1;
@@ -570,25 +572,39 @@ static int raid5_end_read_request(struct bio * bi, unsigned int bytes_done,
 		set_bit(R5_UPTODATE, &sh->dev[i].flags);
 #endif
 		if (test_bit(R5_ReadError, &sh->dev[i].flags)) {
-			printk(KERN_INFO "raid5: read error corrected!!\n");
+			rdev = conf->disks[i].rdev;
+			printk(KERN_INFO "raid5:%s: read error corrected (%lu sectors at %llu on %s)\n",
+			       mdname(conf->mddev), STRIPE_SECTORS,
+			       (unsigned long long)sh->sector + rdev->data_offset,
+			       bdevname(rdev->bdev, b));
 			clear_bit(R5_ReadError, &sh->dev[i].flags);
 			clear_bit(R5_ReWrite, &sh->dev[i].flags);
 		}
 		if (atomic_read(&conf->disks[i].rdev->read_errors))
 			atomic_set(&conf->disks[i].rdev->read_errors, 0);
 	} else {
+		const char *bdn = bdevname(conf->disks[i].rdev->bdev, b);
 		int retry = 0;
+		rdev = conf->disks[i].rdev;
+
 		clear_bit(R5_UPTODATE, &sh->dev[i].flags);
-		atomic_inc(&conf->disks[i].rdev->read_errors);
+		atomic_inc(&rdev->read_errors);
 		if (conf->mddev->degraded)
-			printk(KERN_WARNING "raid5: read error not correctable.\n");
+			printk(KERN_WARNING "raid5:%s: read error not correctable (sector %llu on %s).\n",
+			       mdname(conf->mddev),
+			       (unsigned long long)sh->sector + rdev->data_offset,
+			       bdn);
 		else if (test_bit(R5_ReWrite, &sh->dev[i].flags))
 			/* Oh, no!!! */
-			printk(KERN_WARNING "raid5: read error NOT corrected!!\n");
-		else if (atomic_read(&conf->disks[i].rdev->read_errors)
+			printk(KERN_WARNING "raid5:%s: read error NOT corrected!! (sector %llu on %s).\n",
+			       mdname(conf->mddev),
+			       (unsigned long long)sh->sector + rdev->data_offset,
+			       bdn);
+		else if (atomic_read(&rdev->read_errors)
 			 > conf->max_nr_stripes)
 			printk(KERN_WARNING
-			       "raid5: Too many read errors, failing device.\n");
+			       "raid5:%s: Too many read errors, failing device %s.\n",
+			       mdname(conf->mddev), bdn);
 		else
 			retry = 1;
 		if (retry)
@@ -596,7 +612,7 @@ static int raid5_end_read_request(struct bio * bi, unsigned int bytes_done,
 		else {
 			clear_bit(R5_ReadError, &sh->dev[i].flags);
 			clear_bit(R5_ReWrite, &sh->dev[i].flags);
-			md_error(conf->mddev, conf->disks[i].rdev);
+			md_error(conf->mddev, rdev);
 		}
 	}
 	rdev_dec_pending(conf->disks[i].rdev, conf->mddev);