CVSROOT: /cvs Module name: src Changes by: mi...@cvs.openbsd.org 2017/06/06 15:12:01
Modified files: sys/dev/pv : xbf.c Log message: Rewrite the driver to handle 64kb transfers Although several codepaths in the kernel such as coredump and buffercache read-ahead feature assume that underlying hardware is capable of handling 64kb transfers without any issues, xbf was setup to rely on a single descriptor per transfer which limited the maximum size of an individual transfer to 11 4k segments amounting to 44k bytes. To avoid overbooking, a metadata object is allocated for each transfer to keep track of associated descriptors limiting the maximum amount of outstanding transfers to half the ring size. The issue was reported by Dan Cross <crossd at gmail.com>, thanks!