On Sun 01 Mar 21:50 PST 2020, Manivannan Sadhasivam wrote:
> Hi Bjorn,
>
> Thanks for the fix. I have tested this and it works perfectly!
>
> On Sun, Mar 01, 2020 at 07:25:26PM -0800, Bjorn Andersson wrote:
> > Lost in the translation from the user space implementation was the
> > detail that HELLO mesages must be exchanged between each node pair. As
> > such the incoming HELLO must be replied to.
> >
>
> Err. I thought the say_hello() part in ctrl_cmd_hello() was redundant, so
> removed it :P
>
> Sorry for that.
>
No worries.
> > Similar to the previous implementation no effort is made to prevent two
> > Linux boxes from continuously sending HELLO messages back and forth,
> > this is left to a follow up patch.
> >
> > say_hello() is moved, to facilitate the new call site.
> >
> > Fixes: 0c2204a4ad71 ("net: qrtr: Migrate nameservice to kernel from userspace")
> > Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
> > ---
> > net/qrtr/ns.c | 54 ++++++++++++++++++++++++++++-----------------------
> > 1 file changed, 30 insertions(+), 24 deletions(-)
> >
> > diff --git a/net/qrtr/ns.c b/net/qrtr/ns.c
> > index 7bfde01f4e8a..e3f11052b5f6 100644
> > --- a/net/qrtr/ns.c
> > +++ b/net/qrtr/ns.c
> > @@ -286,9 +286,38 @@ static int server_del(struct qrtr_node *node, unsigned int port)
> > return 0;
> > }
> >
> > +static int say_hello(struct sockaddr_qrtr *dest)
> > +{
> > + struct qrtr_ctrl_pkt pkt;
> > + struct msghdr msg = { };
> > + struct kvec iv;
> > + int ret;
> > +
> > + iv.iov_base = &pkt;
> > + iv.iov_len = sizeof(pkt);
> > +
> > + memset(&pkt, 0, sizeof(pkt));
> > + pkt.cmd = cpu_to_le32(QRTR_TYPE_HELLO);
> > +
> > + msg.msg_name = (struct sockaddr *)dest;
> > + msg.msg_namelen = sizeof(*dest);
> > +
> > + ret = kernel_sendmsg(qrtr_ns.sock, &msg, &iv, 1, sizeof(pkt));
> > + if (ret < 0)
> > + pr_err("failed to send hello msg\n");
> > +
> > + return ret;
> > +}
> > +
> > /* Announce the list of servers registered on the local node */
> > static int ctrl_cmd_hello(struct sockaddr_qrtr *sq)
> > {
> > + int ret;
> > +
> > + ret = say_hello(sq); > > + if (ret < 0)
> > + return ret;
> > +
> > return announce_servers(sq);
> > }
> >
> > @@ -566,29 +595,6 @@ static void ctrl_cmd_del_lookup(struct sockaddr_qrtr *from,
> > }
> > }
> >
> > -static int say_hello(void)
> > -{
> > - struct qrtr_ctrl_pkt pkt;
> > - struct msghdr msg = { };
> > - struct kvec iv;
> > - int ret;
> > -
> > - iv.iov_base = &pkt;
> > - iv.iov_len = sizeof(pkt);
> > -
> > - memset(&pkt, 0, sizeof(pkt));
> > - pkt.cmd = cpu_to_le32(QRTR_TYPE_HELLO);
> > -
> > - msg.msg_name = (struct sockaddr *)&qrtr_ns.bcast_sq;
> > - msg.msg_namelen = sizeof(qrtr_ns.bcast_sq);
> > -
> > - ret = kernel_sendmsg(qrtr_ns.sock, &msg, &iv, 1, sizeof(pkt));
> > - if (ret < 0)
> > - pr_err("failed to send hello msg\n");
> > -
> > - return ret;
> > -}
> > -
> > static void qrtr_ns_worker(struct work_struct *work)
> > {
> > const struct qrtr_ctrl_pkt *pkt;
> > @@ -725,7 +731,7 @@ void qrtr_ns_init(struct work_struct *work)
> > if (!qrtr_ns.workqueue)
> > goto err_sock;
> >
> > - ret = say_hello();
> > + ret = say_hello(&qrtr_ns.bcast_sq);
>
> Why do you want to pass a global variable here? Why can't it be used directly
> in say_hello() as done before?
>
Because I changed the prototype of say_hello() so that we pass the
destination address; here that's the broadcast address, in
ctrl_cmd_hello() it's the specific sender of the incoming hello that we
want to respond to.
Regards,
Bjorn
> Other than that,
>
> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
> Tested-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
>
> Thanks,
> Mani
>
> > if (ret < 0)
> > goto err_wq;
> >
> > --
> > 2.24.0
> >
