Re: [PATCH 09/13] ibmvfc: implement channel enquiry and setup commands

From: Brian King
Date: Fri Nov 27 2020 - 12:49:55 EST


On 11/25/20 7:48 PM, Tyrel Datwyler wrote:
> --- a/drivers/scsi/ibmvscsi/ibmvfc.c
> +++ b/drivers/scsi/ibmvscsi/ibmvfc.c

> @@ -4462,6 +4464,118 @@ static void ibmvfc_discover_targets(struct ibmvfc_host *vhost)
> ibmvfc_link_down(vhost, IBMVFC_LINK_DEAD);
> }
>
> +static void ibmvfc_channel_setup_done(struct ibmvfc_event *evt)
> +{
> + struct ibmvfc_host *vhost = evt->vhost;
> + u32 mad_status = be16_to_cpu(evt->xfer_iu->channel_setup.common.status);
> + int level = IBMVFC_DEFAULT_LOG_LEVEL;
> +
> + ibmvfc_free_event(evt);
> +
> + switch (mad_status) {
> + case IBMVFC_MAD_SUCCESS:
> + ibmvfc_dbg(vhost, "Channel Setup succeded\n");
> + vhost->do_enquiry = 0;
> + break;
> + case IBMVFC_MAD_FAILED:
> + level += ibmvfc_retry_host_init(vhost);
> + ibmvfc_log(vhost, level, "Channel Setup failed\n");
> + fallthrough;
> + case IBMVFC_MAD_DRIVER_FAILED:
> + return;
> + default:
> + dev_err(vhost->dev, "Invalid Channel Setup response: 0x%x\n",
> + mad_status);
> + ibmvfc_link_down(vhost, IBMVFC_LINK_DEAD);
> + return;
> + }
> +
> + ibmvfc_set_host_action(vhost, IBMVFC_HOST_ACTION_QUERY);
> + wake_up(&vhost->work_wait_q);
> +}
> +
> +static void ibmvfc_channel_setup(struct ibmvfc_host *vhost)
> +{
> + struct ibmvfc_channel_setup_mad *mad;
> + struct ibmvfc_channel_setup *setup_buf = vhost->channel_setup_buf;
> + struct ibmvfc_event *evt = ibmvfc_get_event(vhost);
> +
> + memset(setup_buf, 0, sizeof(*setup_buf));
> + setup_buf->flags = cpu_to_be32(IBMVFC_CANCEL_CHANNELS);
> +
> + ibmvfc_init_event(evt, ibmvfc_channel_setup_done, IBMVFC_MAD_FORMAT);
> + mad = &evt->iu.channel_setup;
> + memset(mad, 0, sizeof(*mad));
> + mad->common.version = cpu_to_be32(1);
> + mad->common.opcode = cpu_to_be32(IBMVFC_CHANNEL_SETUP);
> + mad->common.length = cpu_to_be16(sizeof(*mad));
> + mad->buffer.va = cpu_to_be64(vhost->channel_setup_dma);
> + mad->buffer.len = cpu_to_be32(sizeof(*vhost->channel_setup_buf));
> +
> + ibmvfc_set_host_action(vhost, IBMVFC_HOST_ACTION_INIT_WAIT);
> +
> + if (!ibmvfc_send_event(evt, vhost, default_timeout))
> + ibmvfc_dbg(vhost, "Sent channel setup\n");
> + else
> + ibmvfc_link_down(vhost, IBMVFC_LINK_DOWN);
> +}
> +
> +static void ibmvfc_channel_enquiry_done(struct ibmvfc_event *evt)
> +{
> + struct ibmvfc_host *vhost = evt->vhost;
> + struct ibmvfc_channel_enquiry *rsp = &evt->xfer_iu->channel_enquiry;
> + u32 mad_status = be16_to_cpu(rsp->common.status);
> + int level = IBMVFC_DEFAULT_LOG_LEVEL;
> +
> + switch (mad_status) {
> + case IBMVFC_MAD_SUCCESS:
> + ibmvfc_dbg(vhost, "Channel Enquiry succeeded\n");
> + vhost->max_vios_scsi_channels = be32_to_cpu(rsp->num_scsi_subq_channels);

You need a ibmvfc_free_event(evt) here so you don't leak events.

> + break;
> + case IBMVFC_MAD_FAILED:
> + level += ibmvfc_retry_host_init(vhost);
> + ibmvfc_log(vhost, level, "Channel Enquiry failed\n");
> + ibmvfc_free_event(evt);

Looks like you are freeing this event twice due to the fallthrough...

> + fallthrough;
> + case IBMVFC_MAD_DRIVER_FAILED:
> + ibmvfc_free_event(evt);
> + return;
> + default:
> + dev_err(vhost->dev, "Invalid Channel Enquiry response: 0x%x\n",
> + mad_status);
> + ibmvfc_link_down(vhost, IBMVFC_LINK_DEAD);
> + ibmvfc_free_event(evt);
> + return;
> + }
> +
> + ibmvfc_channel_setup(vhost);
> +}
> +



--
Brian King
Power Linux I/O
IBM Linux Technology Center