Re: [PATCH v2 2/3] scsi: ufs: Modulize ufs-bsg

Vignesh Raghavendra
2019-12-12T05:40:29Z

Hi,

On 11/12/19 2:19 pm, Can Guo wrote:
> In order to improve the flexibility of ufs-bsg, modulizing it is a good
> choice. This change introduces tristate to ufs-bsg to allow users compile
> it as an external module.
>
> Signed-off-by: Can Guo <cang@codeaurora.org>
> ---
[...]
> -int ufs_bsg_probe(struct ufs_hba *hba)
> +static int ufs_bsg_probe(struct ufs_hba *hba)
> {
> - struct device *bsg_dev = &hba->bsg_dev;
> + struct device *bsg_dev;
> struct Scsi_Host *shost = hba->host;
> struct device *parent = &shost->shost_gendev;
> struct request_queue *q;
> int ret;
>
> + bsg_dev = kzalloc(sizeof(*bsg_dev), GFP_KERNEL);
> + if (!bsg_dev)
> + return -ENOMEM;
> +
> + hba->bsg_dev = bsg_dev;
> device_initialize(bsg_dev);
>
> bsg_dev->parent = get_device(parent);
> @@ -217,6 +225,41 @@ int ufs_bsg_probe(struct ufs_hba *hba)
>
> out:
> dev_err(bsg_dev, "fail to initialize a bsg dev %d\n", shost->host_no);
> + hba->bsg_dev = NULL;

Don't we need to free the associated memory before assigning to NULL?
Alternatively can allocation be made with devm_ APIs instead?

> put_device(bsg_dev);
> return ret;
> }
> +
> +static int __init ufs_bsg_init(void)
> +{
> + struct list_head *hba_list = NULL;
> + struct ufs_hba *hba;
> + int ret = 0;
> +
> + ufshcd_get_hba_list_lock(&hba_list);
> + list_for_each_entry(hba, hba_list, list) {
> + ret = ufs_bsg_probe(hba);
> + if (ret)
> + break;
> + }

So IIUC, if ufs_bsg_probe() fails for one of the hba instances in the
list, then we fail to create bsg device for all remaining instances that
follow, which seems too harsh.

Regards
Vignesh