Re: [PATCH 19/24] dm: remove dm_get_dev_t

[Mike Snitzer <snitzer@kernel.org>]

On Tue, May 23 2023 at  3:45P -0400,
Christoph Hellwig <hch@lst.de> wrote:

> Open code dm_get_dev_t in the only remaining caller, and propagate the
> exact error code from lookup_bdev and early_lookup_bdev.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  drivers/md/dm-table.c         | 20 ++++----------------
>  include/linux/device-mapper.h |  2 --
>  2 files changed, 4 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
> index 05aa16da43b0d5..e997f4322a9967 100644
> --- a/drivers/md/dm-table.c
> +++ b/drivers/md/dm-table.c
> @@ -323,20 +323,6 @@ static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode,
>  	return 0;
>  }
>  
> -/*
> - * Convert the path to a device
> - */
> -dev_t dm_get_dev_t(const char *path)
> -{
> -	dev_t dev;
> -
> -	if (lookup_bdev(path, &dev) &&
> -	    early_lookup_bdev(path, &dev))
> -		return 0;
> -	return dev;
> -}
> -EXPORT_SYMBOL_GPL(dm_get_dev_t);
> -
>  /*
>   * Add a device to the list, or just increment the usage count if
>   * it's already present.
> @@ -359,8 +345,10 @@ int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode,
>  		if (MAJOR(dev) != major || MINOR(dev) != minor)
>  			return -EOVERFLOW;
>  	} else {
> -		dev = dm_get_dev_t(path);
> -		if (!dev)
> +		r = lookup_bdev(path, &dev);
> +		if (r)
> +			r = early_lookup_bdev(path, &dev);
> +		if (r)
>  			return -ENODEV;
>  	}
>  	if (dev == disk_devt(t->md->disk))

OK, but you aren't actually propagating the exact error code.  Did
you intend to change the return from -ENODEV to r?

Mike