[PATCH] scsi: ufs: continue to boot even with Boot LUN is disabled

[PATCH] scsi: ufs: continue to boot even with Boot LUN is disabled

[Huanlin Ke]

Several configurable fields of the Device Descriptor and the Unit
Descriptors determine the Boot LUN status. The bBootEnable field and
the bBootLunEn attribute is set to zero by default, so the Boot LUN is
disabled by default.

At which point the scsi device add for Boot LUN will fail, but we can
continue to use the ufs device in fact. This failure shouldn't abort the
device boot.

Signed-off-by: Huanlin Ke <kehuanlin@pinecone.net>
---
 drivers/scsi/ufs/ufshcd.c | 19 ++++++++-----------
 1 file changed, 8 insertions(+), 11 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 794a460..bff84be 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -5998,25 +5998,22 @@ static int ufshcd_scsi_add_wlus(struct ufs_hba *hba)
 	}
 	scsi_device_put(hba->sdev_ufs_device);
 
-	sdev_boot = __scsi_add_device(hba->host, 0, 0,
-		ufshcd_upiu_wlun_to_scsi_wlun(UFS_UPIU_BOOT_WLUN), NULL);
-	if (IS_ERR(sdev_boot)) {
-		ret = PTR_ERR(sdev_boot);
-		goto remove_sdev_ufs_device;
-	}
-	scsi_device_put(sdev_boot);
-
 	sdev_rpmb = __scsi_add_device(hba->host, 0, 0,
 		ufshcd_upiu_wlun_to_scsi_wlun(UFS_UPIU_RPMB_WLUN), NULL);
 	if (IS_ERR(sdev_rpmb)) {
 		ret = PTR_ERR(sdev_rpmb);
-		goto remove_sdev_boot;
+		goto remove_sdev_ufs_device;
 	}
 	scsi_device_put(sdev_rpmb);
+
+	sdev_boot = __scsi_add_device(hba->host, 0, 0,
+		ufshcd_upiu_wlun_to_scsi_wlun(UFS_UPIU_BOOT_WLUN), NULL);
+	if (IS_ERR(sdev_boot))
+		dev_err(hba->dev, "%s: BOOT WLUN not found\n", __func__);
+	else
+		scsi_device_put(sdev_boot);
 	goto out;
 
-remove_sdev_boot:
-	scsi_remove_device(sdev_boot);
 remove_sdev_ufs_device:
 	scsi_remove_device(hba->sdev_ufs_device);
 out:
-- 
2.7.4

Re: [PATCH] scsi: ufs: continue to boot even with Boot LUN is disabled

[Subhash Jadavani]

On 2017-09-22 03:31, Huanlin Ke wrote:
> Several configurable fields of the Device Descriptor and the Unit
> Descriptors determine the Boot LUN status. The bBootEnable field and
> the bBootLunEn attribute is set to zero by default, so the Boot LUN is
> disabled by default.
> 
> At which point the scsi device add for Boot LUN will fail, but we can
> continue to use the ufs device in fact. This failure shouldn't abort 
> the
> device boot.
> 
> Signed-off-by: Huanlin Ke <kehuanlin@pinecone.net>
> ---
>  drivers/scsi/ufs/ufshcd.c | 19 ++++++++-----------
>  1 file changed, 8 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index 794a460..bff84be 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -5998,25 +5998,22 @@ static int ufshcd_scsi_add_wlus(struct ufs_hba 
> *hba)
>  	}
>  	scsi_device_put(hba->sdev_ufs_device);
> 
> -	sdev_boot = __scsi_add_device(hba->host, 0, 0,
> -		ufshcd_upiu_wlun_to_scsi_wlun(UFS_UPIU_BOOT_WLUN), NULL);
> -	if (IS_ERR(sdev_boot)) {
> -		ret = PTR_ERR(sdev_boot);
> -		goto remove_sdev_ufs_device;
> -	}
> -	scsi_device_put(sdev_boot);
> -
>  	sdev_rpmb = __scsi_add_device(hba->host, 0, 0,
>  		ufshcd_upiu_wlun_to_scsi_wlun(UFS_UPIU_RPMB_WLUN), NULL);
>  	if (IS_ERR(sdev_rpmb)) {
>  		ret = PTR_ERR(sdev_rpmb);
> -		goto remove_sdev_boot;
> +		goto remove_sdev_ufs_device;
>  	}
>  	scsi_device_put(sdev_rpmb);
> +
> +	sdev_boot = __scsi_add_device(hba->host, 0, 0,
> +		ufshcd_upiu_wlun_to_scsi_wlun(UFS_UPIU_BOOT_WLUN), NULL);
> +	if (IS_ERR(sdev_boot))
> +		dev_err(hba->dev, "%s: BOOT WLUN not found\n", __func__);
> +	else
> +		scsi_device_put(sdev_boot);
>  	goto out;
> 
> -remove_sdev_boot:
> -	scsi_remove_device(sdev_boot);
>  remove_sdev_ufs_device:
>  	scsi_remove_device(hba->sdev_ufs_device);
>  out:

Looks good to me.
Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org>

-- 
The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

Re: [PATCH] scsi: ufs: continue to boot even with Boot LUN is disabled

[Martin K. Petersen]

Huanlin,

> Several configurable fields of the Device Descriptor and the Unit
> Descriptors determine the Boot LUN status. The bBootEnable field and
> the bBootLunEn attribute is set to zero by default, so the Boot LUN is
> disabled by default.
>
> At which point the scsi device add for Boot LUN will fail, but we can
> continue to use the ufs device in fact. This failure shouldn't abort the
> device boot.

Applied to 4.15/scsi-queue. Thank you!

-- 
Martin K. Petersen	Oracle Linux Engineering