Re: [PATCH v7 6/6] hisi_acc_vfio_pci: update function return values.

[liulongfang <liulongfang@huawei.com>]

on 2025/4/15 17:25, Shameerali Kolothum Thodi wrote:
> 
> 
>> -----Original Message-----
>> From: liulongfang <liulongfang@huawei.com>
>> Sent: Friday, April 11, 2025 4:59 AM
>> To: alex.williamson@redhat.com; jgg@nvidia.com; Shameerali Kolothum
>> Thodi <shameerali.kolothum.thodi@huawei.com>; Jonathan Cameron
>> <jonathan.cameron@huawei.com>
>> Cc: kvm@vger.kernel.org; linux-kernel@vger.kernel.org;
>> linuxarm@openeuler.org; liulongfang <liulongfang@huawei.com>
>> Subject: [PATCH v7 6/6] hisi_acc_vfio_pci: update function return values.
>>
>> In this driver file, many functions call sub-functions and use ret
>> to store the error code of the sub-functions.
>> However, instead of directly returning ret to the caller, they use a
>> converted error code, which prevents the end-user from clearly
>> understanding the root cause of the error.
>> Therefore, the code needs to be modified to directly return the error
>> code from the sub-functions.
>>
>> Signed-off-by: Longfang Liu <liulongfang@huawei.com>
>> ---
>>  drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c | 16 ++++++++--------
>>  1 file changed, 8 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
>> b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
>> index d12a350440d3..c63e302ac092 100644
>> --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
>> +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
>> @@ -392,7 +392,7 @@ static int vf_qm_check_match(struct
>> hisi_acc_vf_core_device *hisi_acc_vdev,
>>  	ret = vf_qm_version_check(vf_data, dev);
>>  	if (ret) {
>>  		dev_err(dev, "failed to match ACC_DEV_MAGIC\n");
>> -		return -EINVAL;
>> +		return ret;
>>  	}
>>
>>  	if (vf_data->dev_id != hisi_acc_vdev->vf_dev->device) {
>> @@ -404,7 +404,7 @@ static int vf_qm_check_match(struct
>> hisi_acc_vf_core_device *hisi_acc_vdev,
>>  	ret = qm_get_vft(vf_qm, &vf_qm->qp_base);
>>  	if (ret <= 0) {
>>  		dev_err(dev, "failed to get vft qp nums\n");
>> -		return -EINVAL;
>> +		return ret;
>>  	}
>>
>>  	if (ret != vf_data->qp_num) {
>> @@ -501,7 +501,7 @@ static int vf_qm_load_data(struct
>> hisi_acc_vf_core_device *hisi_acc_vdev,
>>  	ret = qm_write_regs(qm, QM_VF_STATE, &vf_data->vf_qm_state, 1);
>>  	if (ret) {
>>  		dev_err(dev, "failed to write QM_VF_STATE\n");
>> -		return -EINVAL;
>> +		return ret;
>>  	}
>>  	hisi_acc_vdev->vf_qm_state = vf_data->vf_qm_state;
>>
>> @@ -542,7 +542,7 @@ static int vf_qm_read_data(struct hisi_qm *vf_qm,
>> struct acc_vf_data *vf_data)
>>
>>  	ret = qm_get_regs(vf_qm, vf_data);
>>  	if (ret)
>> -		return -EINVAL;
>> +		return ret;
>>
>>  	/* Every reg is 32 bit, the dma address is 64 bit. */
>>  	vf_data->eqe_dma = vf_data->qm_eqc_dw[QM_XQC_ADDR_HIGH];
>> @@ -556,13 +556,13 @@ static int vf_qm_read_data(struct hisi_qm
>> *vf_qm, struct acc_vf_data *vf_data)
>>  	ret = qm_get_sqc(vf_qm, &vf_data->sqc_dma);
>>  	if (ret) {
>>  		dev_err(dev, "failed to read SQC addr!\n");
>> -		return -EINVAL;
>> +		return ret;
>>  	}
>>
>>  	ret = qm_get_cqc(vf_qm, &vf_data->cqc_dma);
>>  	if (ret) {
>>  		dev_err(dev, "failed to read CQC addr!\n");
>> -		return -EINVAL;
>> +		return ret;
>>  	}
>>
>>  	return 0;
>> @@ -588,7 +588,7 @@ static int vf_qm_state_save(struct
>> hisi_acc_vf_core_device *hisi_acc_vdev,
>>
>>  	ret = vf_qm_read_data(vf_qm, vf_data);
>>  	if (ret)
>> -		return -EINVAL;
>> +		return ret;
>>
>>  	migf->total_length = sizeof(struct acc_vf_data);
>>  	/* Save eqc and aeqc interrupt information */
>> @@ -1379,7 +1379,7 @@ static int hisi_acc_vf_debug_check(struct seq_file
>> *seq, struct vfio_device *vde
>>  	ret = qm_wait_dev_not_ready(vf_qm);
>>  	if (ret) {
>>  		seq_puts(seq, "VF device not ready!\n");
>> -		return -EBUSY;
>> +		return ret;
>>  	}
>>
>>  	return 0;
> 
> Any reason you avoided few other instances here?
>

In the next version, I will add the modification.

Thank you.
Longfang.

> 1. qemu_set_regs() --> hisi_qm_wait_mb_ready() -->ret -EBUSY;
> 2. vf_qm_cache_wb() ret -EINVAL on -ETIMEOUT.
> 
> With the above addressed,
> 
> Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
> 
> Thanks,
> Shameer
> 
> .
>