On 2/9/22 1:24 PM, Mike Christie wrote:
> On 2/8/22 11:24 AM, Bart Van Assche wrote:
>> Instead of storing the iSCSI task pointer and the session age in the SCSI
>> pointer, use command-private variables. This patch prepares for removal of
>> the SCSI pointer from struct scsi_cmnd.
>>
>> The list of iSCSI drivers has been obtained as follows:
>> $ git grep -lw iscsi_host_alloc
>> drivers/infiniband/ulp/iser/iscsi_iser.c
>> drivers/scsi/be2iscsi/be_main.c
>> drivers/scsi/bnx2i/bnx2i_iscsi.c
>> drivers/scsi/cxgbi/libcxgbi.c
>> drivers/scsi/iscsi_tcp.c
>> drivers/scsi/libiscsi.c
>> drivers/scsi/qedi/qedi_main.c
>> drivers/scsi/qla4xxx/ql4_os.c
>> include/scsi/libiscsi.h
>>
>> Note: it is not clear to me how the qla4xxx driver can work without this
>> patch since it uses the scsi_cmnd::SCp.ptr member for two different
>> purposes:
>
> qla4xxx doesn't use libiscsi for scsi_cmd based IO. It has it's own
> queuecommand, completion path and error handlers, because it offloads
> the entire scsi cmd operation.
>
> It only uses libiscsi for iscsi passthrough IO which doesn't use the
> scsi_cmnd.
>
>
>>
>> static void qedi_conn_free_login_resources(struct qedi_ctx *qedi,
>> diff --git a/drivers/scsi/qla4xxx/ql4_def.h b/drivers/scsi/qla4xxx/ql4_def.h
>> index 69a590546bf9..a122909169ee 100644
>> --- a/drivers/scsi/qla4xxx/ql4_def.h
>> +++ b/drivers/scsi/qla4xxx/ql4_def.h
>> @@ -216,11 +216,18 @@
>> #define IDC_COMP_TOV 5
>> #define LINK_UP_COMP_TOV 30
>>
>> -#define CMD_SP(Cmnd) ((Cmnd)->SCp.ptr)
>> +struct qla4xxx_cmd_priv {
>> + struct iscsi_cmd iscsi_data; /* must be the first member */
>> + struct srb *srb;
>> +};
>
>
> So you don't need the iscsi_cmd above.
Mike's of course right about qla4xxx, but it still calls iscsi_host_alloc
so only accounting for the srb pointer in cmd_size is going to trigger the
WARN_ON_ONCE Bart added.
- Chris Leech
