[PATCH md 000 of 2] Introduction

[PATCH md 000 of 2] Introduction

[NeilBrown]

Hi again,
 two more patches for md follow.  Both raid1 related.
 These are happy to sit in the queue for after 2.6.12.

Thanks,
NeilBrown

 [PATCH md 001 of 2] Cause md/raid1 to "repack" working devices when number of drives is changed.
 [PATCH md 002 of 2] Make sure recovery happens when add_new_disk is used for hot_add

[PATCH md 001 of 2] Cause md/raid1 to "repack" working devices when number of drives is changed.

[NeilBrown]

i.e. missing or failed drives are moved to the end of the list.
The means a 3 drive md array with the first drive missing can be shrunk
to a two drive array.  Currently that isn't possible.

Also, the "last_used" device number might be out-of-range after the number
of devices is reduced, so we set it to 0.

Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>

### Diffstat output
 ./drivers/md/raid1.c |   24 +++++++++++++++++++-----
 1 files changed, 19 insertions(+), 5 deletions(-)

diff ./drivers/md/raid1.c~current~ ./drivers/md/raid1.c
--- ./drivers/md/raid1.c~current~	2005-05-13 14:47:35.000000000 +1000
+++ ./drivers/md/raid1.c	2005-05-13 14:47:44.000000000 +1000
@@ -1485,17 +1485,26 @@ static int raid1_reshape(mddev_t *mddev,
 	 * We allocate a new r1bio_pool if we can.
 	 * Then raise a device barrier and wait until all IO stops.
 	 * Then resize conf->mirrors and swap in the new r1bio pool.
+	 *
+	 * At the same time, we "pack" the devices so that all the missing
+	 * devices have the higher raid_disk numbers.
 	 */
 	mempool_t *newpool, *oldpool;
 	struct pool_info *newpoolinfo;
 	mirror_info_t *newmirrors;
 	conf_t *conf = mddev_to_conf(mddev);
+	int cnt;
 
-	int d;
+	int d, d2;
 
-	for (d= raid_disks; d < conf->raid_disks; d++)
-		if (conf->mirrors[d].rdev)
+	if (raid_disks < conf->raid_disks) {
+		cnt=0;
+		for (d= 0; d < conf->raid_disks; d++)
+			if (conf->mirrors[d].rdev)
+				cnt++;
+		if (cnt > raid_disks)
 			return -EBUSY;
+	}
 
 	newpoolinfo = kmalloc(sizeof(*newpoolinfo), GFP_KERNEL);
 	if (!newpoolinfo)
@@ -1526,8 +1535,12 @@ static int raid1_reshape(mddev_t *mddev,
 	/* ok, everything is stopped */
 	oldpool = conf->r1bio_pool;
 	conf->r1bio_pool = newpool;
-	for (d=0; d < raid_disks && d < conf->raid_disks; d++)
-		newmirrors[d] = conf->mirrors[d];
+
+	for (d=d2=0; d < conf->raid_disks; d++)
+		if (conf->mirrors[d].rdev) {
+			conf->mirrors[d].rdev->raid_disk = d2;
+			newmirrors[d2++].rdev = conf->mirrors[d].rdev;
+		}
 	kfree(conf->mirrors);
 	conf->mirrors = newmirrors;
 	kfree(conf->poolinfo);
@@ -1536,6 +1549,7 @@ static int raid1_reshape(mddev_t *mddev,
 	mddev->degraded += (raid_disks - conf->raid_disks);
 	conf->raid_disks = mddev->raid_disks = raid_disks;
 
+	conf->last_used = 0; /* just make sure it is in-range */
 	spin_lock_irq(&conf->resync_lock);
 	conf->barrier--;
 	spin_unlock_irq(&conf->resync_lock);

[PATCH md 002 of 2] Make sure recovery happens when add_new_disk is used for hot_add

[NeilBrown]

Currently if add_new_disk is used to hot-add a drive to a degraded
array, recovery doesn't start ... because we didn't tell it to.

Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>

### Diffstat output
 ./drivers/md/md.c |    2 ++
 1 files changed, 2 insertions(+)

diff ./drivers/md/md.c~current~ ./drivers/md/md.c
--- ./drivers/md/md.c~current~	2005-05-13 14:47:35.000000000 +1000
+++ ./drivers/md/md.c	2005-05-13 14:48:22.000000000 +1000
@@ -2232,6 +2232,8 @@ static int add_new_disk(mddev_t * mddev,
 		err = bind_rdev_to_array(rdev, mddev);
 		if (err)
 			export_rdev(rdev);
+
+		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
 		if (mddev->thread)
 			md_wakeup_thread(mddev->thread);
 		return err;

[PATCH 1/1] md: fix hot add for non-persistent superblock arrays

[Paul Clements]

[-- Attachment #1: Type: text/plain, Size: 181 bytes --]

Neil,

hot add is not working for non-persistent superblock arrays (md is 
trying, and failing, to read a superblock from the new disk)...

attached patch fixes it...

Thanks,
Paul

[-- Attachment #2: md_non_persistent_hot_add.diff --]
[-- Type: text/plain, Size: 742 bytes --]


Signed-Off-By: Paul Clements <paul.clements@steeleye.com>

 md.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletion(-)
diff -purN --exclude-from /export/public/clemep/tmp/dontdiff linux-2.6.12-rc1-mm2-PRISTINE/drivers/md/md.c linux-2.6.12-rc1-mm2/drivers/md/md.c
--- linux-2.6.12-rc1-mm2-PRISTINE/drivers/md/md.c	Fri Mar 25 14:33:36 2005
+++ linux-2.6.12-rc1-mm2/drivers/md/md.c	Thu May 19 16:29:44 2005
@@ -2218,7 +2218,8 @@ static int add_new_disk(mddev_t * mddev,
 			       mdname(mddev));
 			return -EINVAL;
 		}
-		rdev = md_import_device(dev, mddev->major_version,
+		rdev = md_import_device(dev, mddev->persistent ?
+					mddev->major_version : -1,
 					mddev->minor_version);
 		if (IS_ERR(rdev)) {
 			printk(KERN_WARNING 

Re: [PATCH 1/1] md: fix hot add for non-persistent superblock arrays

[Neil Brown]

On Thursday May 19, paul.clements@steeleye.com wrote:
> Neil,
> 
> hot add is not working for non-persistent superblock arrays (md is 
> trying, and failing, to read a superblock from the new disk)...
> 
> attached patch fixes it...

Yep, that looks good, thanks.

NeilBrown

> 
> Thanks,
> Paul
> 
> Signed-Off-By: Paul Clements <paul.clements@steeleye.com>
> 
>  md.c |    3 ++-
>  1 files changed, 2 insertions(+), 1 deletion(-)
> diff -purN --exclude-from /export/public/clemep/tmp/dontdiff linux-2.6.12-rc1-mm2-PRISTINE/drivers/md/md.c linux-2.6.12-rc1-mm2/drivers/md/md.c
> --- linux-2.6.12-rc1-mm2-PRISTINE/drivers/md/md.c	Fri Mar 25 14:33:36 2005
> +++ linux-2.6.12-rc1-mm2/drivers/md/md.c	Thu May 19 16:29:44 2005
> @@ -2218,7 +2218,8 @@ static int add_new_disk(mddev_t * mddev,
>  			       mdname(mddev));
>  			return -EINVAL;
>  		}
> -		rdev = md_import_device(dev, mddev->major_version,
> +		rdev = md_import_device(dev, mddev->persistent ?
> +					mddev->major_version : -1,
>  					mddev->minor_version);
>  		if (IS_ERR(rdev)) {
>  			printk(KERN_WARNING