On 11/27/20 9:46 AM, Brian King wrote:
> On 11/25/20 7:48 PM, Tyrel Datwyler wrote:
>> Allocate a set of Sub-CRQs in advance. During channel setup the client
>> and VIOS negotiate the number of queues the VIOS supports and the number
>> that the client desires to request. Its possible that the final channel
>> resources allocated is less than requested, but the client is still
>> responsible for sending handles for every queue it is hoping for.
>>
>> Also, provide deallocation cleanup routines.
>>
>> Signed-off-by: Tyrel Datwyler <tyr...@linux.ibm.com>
>> ---
>> drivers/scsi/ibmvscsi/ibmvfc.c | 115 +++++++++++++++++++++++++++++++++
>> drivers/scsi/ibmvscsi/ibmvfc.h | 1 +
>> 2 files changed, 116 insertions(+)
>>
>> diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
>> index 260b82e3cc01..571abdb48384 100644
>> --- a/drivers/scsi/ibmvscsi/ibmvfc.c
>> +++ b/drivers/scsi/ibmvscsi/ibmvfc.c
>> @@ -4983,6 +4983,114 @@ static int ibmvfc_init_crq(struct ibmvfc_host *vhost)
>> return retrc;
>> }
>>
>> +static int ibmvfc_register_scsi_channel(struct ibmvfc_host *vhost,
>> + int index)
>> +{
>> + struct device *dev = vhost->dev;
>> + struct vio_dev *vdev = to_vio_dev(dev);
>> + struct ibmvfc_sub_queue *scrq = &vhost->scsi_scrqs.scrqs[index];
>> + int rc = -ENOMEM;
>> +
>> + ENTER;
>> +
>> + scrq->msgs = (struct ibmvfc_sub_crq *)get_zeroed_page(GFP_KERNEL);
>> + if (!scrq->msgs)
>> + return rc;
>> +
>> + scrq->size = PAGE_SIZE / sizeof(*scrq->msgs);
>> + scrq->msg_token = dma_map_single(dev, scrq->msgs, PAGE_SIZE,
>> + DMA_BIDIRECTIONAL);
>> +
>> + if (dma_mapping_error(dev, scrq->msg_token))
>> + goto dma_map_failed;
>> +
>> + rc = h_reg_sub_crq(vdev->unit_address, scrq->msg_token, PAGE_SIZE,
>> + &scrq->cookie, &scrq->hw_irq);
>> +
>> + if (rc) {
>> + dev_warn(dev, "Error registering sub-crq: %d\n", rc);
>> + dev_warn(dev, "Firmware may not support MQ\n");
>> + goto reg_failed;
>> + }
>> +
>> + scrq->hwq_id = index;
>> + scrq->vhost = vhost;
>> +
>> + LEAVE;
>> + return 0;
>> +
>> +reg_failed:
>> + dma_unmap_single(dev, scrq->msg_token, PAGE_SIZE, DMA_BIDIRECTIONAL);
>> +dma_map_failed:
>> + free_page((unsigned long)scrq->msgs);
>> + LEAVE;
>> + return rc;
>> +}
>> +
>> +static void ibmvfc_deregister_scsi_channel(struct ibmvfc_host *vhost, int
>> index)
>> +{
>> + struct device *dev = vhost->dev;
>> + struct vio_dev *vdev = to_vio_dev(dev);
>> + struct ibmvfc_sub_queue *scrq = &vhost->scsi_scrqs.scrqs[index];
>> + long rc;
>> +
>> + ENTER;
>> +
>> + do {
>> + rc = plpar_hcall_norets(H_FREE_SUB_CRQ, vdev->unit_address,
>> + scrq->cookie);
>> + } while (rc == H_BUSY || H_IS_LONG_BUSY(rc));
>> +
>> + if (rc)
>> + dev_err(dev, "Failed to free sub-crq[%d]: rc=%ld\n", index, rc);
>> +
>> + dma_unmap_single(dev, scrq->msg_token, PAGE_SIZE, DMA_BIDIRECTIONAL);
>> + free_page((unsigned long)scrq->msgs);
>> + LEAVE;
>> +}
>> +
>> +static int ibmvfc_init_sub_crqs(struct ibmvfc_host *vhost)
>> +{
>> + int i, j;
>> +
>> + ENTER;
>> +
>> + vhost->scsi_scrqs.scrqs = kcalloc(vhost->client_scsi_channels,
>> + sizeof(*vhost->scsi_scrqs.scrqs),
>> + GFP_KERNEL);
>> + if (!vhost->scsi_scrqs.scrqs)
>> + return -1;
>> +
>> + for (i = 0; i < vhost->client_scsi_channels; i++) {
>> + if (ibmvfc_register_scsi_channel(vhost, i)) {
>> + for (j = i; j > 0; j--)
>> + ibmvfc_deregister_scsi_channel(vhost, j - 1);
>> + kfree(vhost->scsi_scrqs.scrqs);
>> + LEAVE;
>> + return -1;
>> + }
>> + }
>> +
>> + LEAVE;
>> + return 0;
>> +}
>> +
>> +static void ibmvfc_release_sub_crqs(struct ibmvfc_host *vhost)
>> +{
>> + int i;
>> +
>> + ENTER;
>> + if (!vhost->scsi_scrqs.scrqs)
>> + return;
>> +
>> + for (i = 0; i < vhost->client_scsi_channels; i++)
>> + ibmvfc_deregister_scsi_channel(vhost, i);
>> +
>> + vhost->scsi_scrqs.active_queues = 0;
>> + kfree(vhost->scsi_scrqs.scrqs);
>
> Do you want to NULL this out after you free it do you don't keep
> a reference to a freed page around?
This isn't actually a page, but a dynamically allocated array of
ibmvfc_sub_queues, but it should be NULL'ed regardless.
-Tyrel
>
>> + LEAVE;
>> +}
>> +
>> /**
>> * ibmvfc_free_mem - Free memory for vhost
>> * @vhost: ibmvfc host struct
>
>
>
