| Message ID | 20201028184310.7017-1-xie.he.0141@gmail.com |
|---|---|
| Headers | show |
| Series | net: hdlc_fr: Add support for any Ethertype | expand |
On Wed, Oct 28, 2020 at 10:12 PM Xie He <xie.he.0141@gmail.com> wrote: > > The eth_type_trans function is called when we receive frames carrying > Ethernet frames. This function expects a non-NULL pointer as an argument, > and assigns it directly to skb->dev. > > However, the code handling other types of frames first assigns a pointer > to "dev", and then at the end checks whether the value is NULL, and if it > is not NULL, assigns it to skb->dev. > > The two flows are different. Mixing them in this function makes the code > messy. It's better that we convert the second flow to align with how > eth_type_trans does things. > > So this patch changes the code to: first make sure the pointer is not > NULL, then assign it directly to skb->dev. "dev" is no longer needed until > the end where we use it to update stats. No need for dev at all then?
On Thu, Oct 29, 2020 at 10:00 AM Willem de Bruijn <willemdebruijn.kernel@gmail.com> wrote: > > This does change rx_dropped count on errors. Not sure how important > that is. But perhaps good to call out in the commit explicitly if it's > intentional. Yes, this is intentional, because I think we need to count it as a "drop" whenever we drop an skb. I'll note this explicitly in the commit message in the next versions of the patch. Thanks!
On Thu, Oct 29, 2020 at 9:58 AM Willem de Bruijn <willemdebruijn.kernel@gmail.com> wrote: > > No need for dev at all then? Right, there's no need for "dev" at all actually. I kept "dev" just to keep the code for updating "dev->stats" simpler, because otherwise we need to write "skb->dev->stats" instead, and there are 3 lines where we need to write it.
The main purpose of this series is the last patch. The previous 3 patches are just code clean-ups so that the last patch will not make the code too messy. The patches must be applied in sequence. The receiving code of this driver doesn't support arbitrary Ethertype values. It only recognizes a few known Ethertypes when receiving and drops skbs with other Ethertypes. However, the standard document RFC 2427 allows Frame Relay to support any Ethertype values. This series adds support for this. Change from v2: Small fix to the commit message of the 2nd and 3rd patch Change from v1: Small fix to the commit message of the 2nd patch Xie He (4): net: hdlc_fr: Simpify fr_rx by using "goto rx_drop" to drop frames net: hdlc_fr: Change the use of "dev" in fr_rx to make the code cleaner net: hdlc_fr: Improve the initial checks when we receive an skb net: hdlc_fr: Add support for any Ethertype drivers/net/wan/hdlc_fr.c | 119 +++++++++++++++++++++++--------------- 1 file changed, 73 insertions(+), 46 deletions(-)