diff mbox series

[08/10] dm: add add_disk() error handling

Message ID 20210823202930.137278-9-mcgrof@kernel.org (mailing list archive)
State Superseded, archived
Delegated to: Mike Snitzer
Headers show
Series block: first batch of add_disk() error handling conversions | expand

Commit Message

Luis Chamberlain Aug. 23, 2021, 8:29 p.m. UTC
We never checked for errors on add_disk() as this function
returned void. Now that this is fixed, use the shiny new
error handling.

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
---
 drivers/md/dm.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

Comments

Christoph Hellwig Aug. 24, 2021, 6:21 a.m. UTC | #1
On Mon, Aug 23, 2021 at 01:29:28PM -0700, Luis Chamberlain wrote:
> -	add_disk(md->disk);
> +	r = add_disk(md->disk);
> +	if (r)
> +		goto out_cleanup_disk;
>  
>  	r = dm_sysfs_init(md);
> -	if (r) {
> -		del_gendisk(md->disk);
> -		return r;
> -	}
> +	if (r)
> +		goto out_del_gendisk;
>  	md->type = type;
>  	return 0;
> +
> +out_cleanup_disk:
> +	blk_cleanup_disk(md->disk);
> +out_del_gendisk:
> +	del_gendisk(md->disk);
> +	return r;

I think the add_disk should just return r.  If you look at the
callers they eventualy end up in dm_table_destroy, which does
this cleanup.

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Luis Chamberlain Aug. 27, 2021, 6:55 p.m. UTC | #2
On Tue, Aug 24, 2021 at 07:21:30AM +0100, Christoph Hellwig wrote:
> On Mon, Aug 23, 2021 at 01:29:28PM -0700, Luis Chamberlain wrote:
> > -	add_disk(md->disk);
> > +	r = add_disk(md->disk);
> > +	if (r)
> > +		goto out_cleanup_disk;
> >  
> >  	r = dm_sysfs_init(md);
> > -	if (r) {
> > -		del_gendisk(md->disk);
> > -		return r;
> > -	}
> > +	if (r)
> > +		goto out_del_gendisk;
> >  	md->type = type;
> >  	return 0;
> > +
> > +out_cleanup_disk:
> > +	blk_cleanup_disk(md->disk);
> > +out_del_gendisk:
> > +	del_gendisk(md->disk);
> > +	return r;
> 
> I think the add_disk should just return r.  If you look at the
> callers they eventualy end up in dm_table_destroy, which does
> this cleanup.

I don't see it. What part of dm_table_destroy() does this?

  Luis

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Christoph Hellwig Aug. 28, 2021, 7:35 a.m. UTC | #3
On Fri, Aug 27, 2021 at 11:55:14AM -0700, Luis Chamberlain wrote:
> > I think the add_disk should just return r.  If you look at the
> > callers they eventualy end up in dm_table_destroy, which does
> > this cleanup.
> 
> I don't see it. What part of dm_table_destroy() does this?

Sorry, dm_destroy, not dm_table_destroy.  For dm_early_create it's
trivial as that calls both dm_table_destroy and dm_destroy in the error
path.  The normal table_load case is a separate ioctl, but if that
fails userspace needs to call the DM_DEV_REMOVE_CMD to cleanup
the state - similar to any other failure.

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Luis Chamberlain Aug. 30, 2021, 9 p.m. UTC | #4
On Sat, Aug 28, 2021 at 08:35:57AM +0100, Christoph Hellwig wrote:
> On Fri, Aug 27, 2021 at 11:55:14AM -0700, Luis Chamberlain wrote:
> > > I think the add_disk should just return r.  If you look at the
> > > callers they eventualy end up in dm_table_destroy, which does
> > > this cleanup.
> > 
> > I don't see it. What part of dm_table_destroy() does this?
> 
> Sorry, dm_destroy, not dm_table_destroy.  For dm_early_create it's
> trivial as that calls both dm_table_destroy and dm_destroy in the error
> path.  The normal table_load case is a separate ioctl, but if that
> fails userspace needs to call the DM_DEV_REMOVE_CMD to cleanup
> the state - similar to any other failure.

I see, ok sure I'll document this on the commit log as its not so
obvious.

  Luis

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diff mbox series

Patch

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 7981b7287628..cd26fde4ab56 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -2077,15 +2077,21 @@  int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t)
 	if (r)
 		return r;
 
-	add_disk(md->disk);
+	r = add_disk(md->disk);
+	if (r)
+		goto out_cleanup_disk;
 
 	r = dm_sysfs_init(md);
-	if (r) {
-		del_gendisk(md->disk);
-		return r;
-	}
+	if (r)
+		goto out_del_gendisk;
 	md->type = type;
 	return 0;
+
+out_cleanup_disk:
+	blk_cleanup_disk(md->disk);
+out_del_gendisk:
+	del_gendisk(md->disk);
+	return r;
 }
 
 struct mapped_device *dm_get_md(dev_t dev)