Re: [PATCH 01/32] block: Provide blkdev_get_handle_* functions

[Jan Kara <jack@xxxxxxx>]

On Tue 04-07-23 10:28:36, Keith Busch wrote:
> On Tue, Jul 04, 2023 at 02:21:28PM +0200, Jan Kara wrote:
> > +struct bdev_handle *blkdev_get_handle_by_dev(dev_t dev, blk_mode_t mode,
> > +           void *holder, const struct blk_holder_ops *hops)
> > +{
> > +   struct bdev_handle *handle = kmalloc(sizeof(struct bdev_handle),
> > +                                        GFP_KERNEL);
> 
> I believe 'sizeof(*handle)' is the preferred style.

OK.

> > +   struct block_device *bdev;
> > +
> > +   if (!handle)
> > +           return ERR_PTR(-ENOMEM);
> > +   bdev = blkdev_get_by_dev(dev, mode, holder, hops);
> > +   if (IS_ERR(bdev))
> > +           return ERR_CAST(bdev);
> 
> Need a 'kfree(handle)' before the error return. Or would it be simpler
> to get the bdev first so you can check the mode settings against a
> read-only bdev prior to the kmalloc?

Yeah. Good point with kfree(). I'm not sure calling blkdev_get_by_dev()
first will be "simpler" - then we need blkdev_put() in case of kmalloc()
failure. Thanks for review!
 
                                                                Honza
-- 
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR