freebsd with flexible iflib nic queues
59cd0f10b3
The implementation of bus_dmamap_load_ma_triv currently calls _bus_dmamap_load_phys on each page that is part of the passed in buffer. Since each page is treated as an individual buffer, the resulting behaviour is different from the behaviour of _bus_dmamap_load_buffer. This breaks certain drivers, like Xen blkfront. If an unmapped buffer of size 4096 that starts at offset 13 into the first page is passed to the current _bus_dmamap_load_ma implementation (so the ma array contains two pages), the result is that two segments are created, one with a size of 4083 and the other with size 13 (because two independant calls to _bus_dmamap_load_phys are performed, one for each physical page). If the same is done with a mapped buffer and calling _bus_dmamap_load_buffer the result is that only one segment is created, with a size of 4096. This patch relegates the usage of bus_dmamap_load_ma_triv in x86 bounce buffer code to drivers requesting BUS_DMA_KEEP_PG_OFFSET and implements _bus_dmamap_load_ma so that it's behaviour is the same as the mapped version (_bus_dmamap_load_buffer). This patch only modifies the x86 bounce buffer code, other arches are left untouched. Reviewed by: kib, jah Differential Revision: https://reviews.freebsd.org/D888 Sponsored by: Citrix Systems R&D |
||
|---|---|---|
| bin | ||
| cddl | ||
| contrib | ||
| crypto | ||
| etc | ||
| gnu | ||
| include | ||
| kerberos5 | ||
| lib | ||
| libexec | ||
| release | ||
| rescue | ||
| sbin | ||
| secure | ||
| share | ||
| sys | ||
| targets | ||
| tests | ||
| tools | ||
| usr.bin | ||
| usr.sbin | ||
| .arcconfig | ||
| .arclint | ||
| COPYRIGHT | ||
| LOCKS | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc1 | ||
| ObsoleteFiles.inc | ||
| README | ||
| UPDATING | ||
This is the top level of the FreeBSD source directory. This file was last revised on: $FreeBSD$ For copyright information, please see the file COPYRIGHT in this directory (additional copyright information also exists for some sources in this tree - please see the specific source directories for more information). The Makefile in this directory supports a number of targets for building components (or all) of the FreeBSD source tree. See build(7) and http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/makeworld.html for more information, including setting make(1) variables. The `buildkernel` and `installkernel` targets build and install the kernel and the modules (see below). Please see the top of the Makefile in this directory for more information on the standard build targets and compile-time flags. Building a kernel is a somewhat more involved process. See build(7), config(8), and http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig.html for more information. Note: If you want to build and install the kernel with the `buildkernel` and `installkernel` targets, you might need to build world before. More information is available in the handbook. The kernel configuration files reside in the sys/<arch>/conf sub-directory. GENERIC is the default configuration used in release builds. NOTES contains entries and documentation for all possible devices, not just those commonly used. Source Roadmap: --------------- bin System/user commands. cddl Various commands and libraries under the Common Development and Distribution License. contrib Packages contributed by 3rd parties. crypto Cryptography stuff (see crypto/README). etc Template files for /etc. games Amusements. gnu Various commands and libraries under the GNU Public License. Please see gnu/COPYING* for more information. include System include files. kerberos5 Kerberos5 (Heimdal) package. lib System libraries. libexec System daemons. release Release building Makefile & associated tools. rescue Build system for statically linked /rescue utilities. sbin System commands. secure Cryptographic libraries and commands. share Shared resources. sys Kernel sources. tests Regression tests which can be run by Kyua. See tests/README for additional information. tools Utilities for regression testing and miscellaneous tasks. usr.bin User commands. usr.sbin System administration commands. For information on synchronizing your source tree with one or more of the FreeBSD Project's development branches, please see: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/synching.html