Re: [PATCH net v2] drivers/net/wan/hdlc_fr: Add needed_headroom for PVC devices

2020-09-13 Thread Xie He
On Sun, Sep 13, 2020 at 10:26 PM Krzysztof Hałasa wrote: > > Xie He writes: > > > The HDLC device is not actually prepending any header when it is used > > with this driver. When the PVC device has prepended its header and > > handed over the skb to the HDLC device, the HDLC device just hands it

Re: [PATCH net v2] drivers/net/wan/hdlc_fr: Add needed_headroom for PVC devices

2020-09-13 Thread Krzysztof Hałasa
Xie He writes: > The HDLC device is not actually prepending any header when it is used > with this driver. When the PVC device has prepended its header and > handed over the skb to the HDLC device, the HDLC device just hands it > over to the hardware driver for transmission without prepending any

Re: [PATCH net v2] drivers/net/wan/hdlc_fr: Add needed_headroom for PVC devices

2020-09-05 Thread Xie He
On Fri, Sep 4, 2020 at 9:36 PM Jakub Kicinski wrote: > > Applied to net, thank you! Thank you, Jakub!

Re: [PATCH net v2] drivers/net/wan/hdlc_fr: Add needed_headroom for PVC devices

2020-09-04 Thread Jakub Kicinski
On Fri, 4 Sep 2020 18:57:27 -0700 Xie He wrote: > On Fri, Sep 4, 2020 at 6:28 PM Xie He wrote: > > > > The HDLC device is not actually prepending any header when it is used > > with this driver. When the PVC device has prepended its header and > > handed over the skb to the HDLC device, the HDLC d

Re: [PATCH net v2] drivers/net/wan/hdlc_fr: Add needed_headroom for PVC devices

2020-09-04 Thread Xie He
On Fri, Sep 4, 2020 at 6:28 PM Xie He wrote: > > The HDLC device is not actually prepending any header when it is used > with this driver. When the PVC device has prepended its header and > handed over the skb to the HDLC device, the HDLC device just hands it > over to the hardware driver for tran

Re: [PATCH net v2] drivers/net/wan/hdlc_fr: Add needed_headroom for PVC devices

2020-09-04 Thread Xie He
Thank you for your email, Jakub! On Fri, Sep 4, 2020 at 3:14 PM Jakub Kicinski wrote: > > Since this is a tunnel protocol on top of HDLC interfaces, and > hdlc_setup_dev() sets dev->hard_header_len = 16; should we actually > set the needed_headroom to 10 + 16 = 26? I'm not clear on where/if > hdl

Re: [PATCH net v2] drivers/net/wan/hdlc_fr: Add needed_headroom for PVC devices

2020-09-04 Thread Jakub Kicinski
On Wed, 2 Sep 2020 17:06:58 -0700 Xie He wrote: > PVC devices are virtual devices in this driver stacked on top of the > actual HDLC device. They are the devices normal users would use. > PVC devices have two types: normal PVC devices and Ethernet-emulating > PVC devices. > > When transmitting da

[PATCH net v2] drivers/net/wan/hdlc_fr: Add needed_headroom for PVC devices

2020-09-02 Thread Xie He
PVC devices are virtual devices in this driver stacked on top of the actual HDLC device. They are the devices normal users would use. PVC devices have two types: normal PVC devices and Ethernet-emulating PVC devices. When transmitting data with PVC devices, the ndo_start_xmit function will prepend