CVSROOT: /cvs Module name: src Changes by: mi...@cvs.openbsd.org 2016/08/29 08:12:58
Modified files: sys/dev/pv : if_xnf.c Log message: Fixup packet fragment unrolling procedure When bus_dmamap_load fails to load one of the buffers in the mbuf chain, we need to revert all changes to transmit descriptors. The code to do that was prototyped but not tested. However due to how the Tx ring is set up in xnf(4) and generic lack of proper fragment support in the Netfront design we're always limited to having 256 entries for distinct shared memory pages. The mbuf chain is traversed and attempt is made to load every data chunk into a 4k sized DMA map segment which makes it impossible to reference a buffer composed of multiple pages. Current implementation lacks support for this preventing reliable transmission of frames larger than 4k. Bug reported by Kirill Miazine <km at krot ! org>, thanks!