Re: [dpdk-dev] [PATCH] net/i40evf: fix casting between structs

["Wu, Jingjing" <jingjing.wu@intel.com>]

> -----Original Message-----
> From: Yigit, Ferruh
> Sent: Wednesday, November 30, 2016 12:08 AM
> To: Wu, Jingjing <jingjing.wu@intel.com>; dev@dpdk.org
> Cc: Zhang, Helin <helin.zhang@intel.com>
> Subject: Re: [dpdk-dev] [PATCH] net/i40evf: fix casting between structs
> 
> On 11/27/2016 9:35 AM, Jingjing Wu wrote:
> > Casting from structs which lay out data in typed members to structs
> > which have flat memory buffers, will cause problems if the alignment
> > of the former isn't as expected.
> > This patch removes the casting between structs.
> >
> > Fixes: ae19955e7c86 ("i40evf: support reporting PF reset")
> > Signed-off-by: Jingjing Wu <jingjing.wu@intel.com>
> > ---
> >  drivers/net/i40e/i40e_ethdev_vf.c | 27 +++++++++++++++------------
> >  1 file changed, 15 insertions(+), 12 deletions(-)
> >
> > diff --git a/drivers/net/i40e/i40e_ethdev_vf.c
> > b/drivers/net/i40e/i40e_ethdev_vf.c
> > index aa306d6..53d7c87 100644
> > --- a/drivers/net/i40e/i40e_ethdev_vf.c
> > +++ b/drivers/net/i40e/i40e_ethdev_vf.c
> > @@ -1336,8 +1336,9 @@ i40evf_handle_aq_msg(struct rte_eth_dev *dev)
> >  	struct i40e_hw *hw = I40E_DEV_PRIVATE_TO_HW(dev->data-
> >dev_private);
> >  	struct i40e_vf *vf = I40EVF_DEV_PRIVATE_TO_VF(dev->data-
> >dev_private);
> >  	struct i40e_arq_event_info info;
> > -	struct i40e_virtchnl_msg *v_msg;
> > -	uint16_t pending, opcode;
> > +	uint16_t pending, aq_opc;
> > +	enum i40e_virtchnl_ops msg_opc;
> > +	enum i40e_status_code msg_ret;
> >  	int ret;
> >
> >  	info.buf_len = I40E_AQ_BUF_SZ;
> > @@ -1346,7 +1347,6 @@ i40evf_handle_aq_msg(struct rte_eth_dev *dev)
> >  		return;
> >  	}
> >  	info.msg_buf = vf->aq_resp;
> > -	v_msg = (struct i40e_virtchnl_msg *)&info.desc;
> >
> >  	pending = 1;
> >  	while (pending) {
> > @@ -1357,32 +1357,35 @@ i40evf_handle_aq_msg(struct rte_eth_dev *dev)
> >  				    "ret: %d", ret);
> >  			break;
> >  		}
> > -		opcode = rte_le_to_cpu_16(info.desc.opcode);
> > -
> > -		switch (opcode) {
> > +		aq_opc = rte_le_to_cpu_16(info.desc.opcode);
> > +		msg_opc = (enum i40e_virtchnl_ops)rte_le_to_cpu_32(
> > +						  info.desc.cookie_high);
> > +		msg_ret = (enum i40e_status_code)rte_le_to_cpu_32(
> > +						  info.desc.cookie_low);
> 
> What do you think commenting cookie_high is opcode and cookie_low is
> return_value?
> 
OK. Will add some comments.

> > +		switch (aq_opc) {
> >  		case i40e_aqc_opc_send_msg_to_vf:
> > -			if (v_msg->v_opcode == I40E_VIRTCHNL_OP_EVENT)
> > +			if (msg_opc == I40E_VIRTCHNL_OP_EVENT)
> >  				/* process event*/
> >  				i40evf_handle_pf_event(dev, info.msg_buf,
> >  						       info.msg_len);
> >  			else {
> >  				/* read message and it's expected one */
> > -				if (v_msg->v_opcode == vf->pend_cmd) {
> > -					vf->cmd_retval = v_msg->v_retval;
> > +				if (msg_opc == vf->pend_cmd) {
> > +					vf->cmd_retval = msg_ret;
> >  					/* prevent compiler reordering */
> >  					rte_compiler_barrier();
> >  					_clear_cmd(vf);
> >  				} else
> >  					PMD_DRV_LOG(ERR, "command
> mismatch,"
> >  						"expect %u, get %u",
> > -						vf->pend_cmd, v_msg-
> >v_opcode);
> > +						vf->pend_cmd, msg_ret);
> 
> s/msg_ret/msg_opc/ ?
Yes, should use msg_opc here. Thanks!

Will update!


Thanks
Jingjing