Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 15 Aug 2015 15:05:19 +0200
From:      =?UTF-8?B?Um9nZXIgUGF1IE1vbm7DqQ==?= <royger@FreeBSD.org>
To:        "Jason A. Harmening" <jah@FreeBSD.org>, src-committers@freebsd.org,  svn-src-all@freebsd.org, svn-src-head@freebsd.org
Subject:   Re: svn commit: r286787 - head/sys/x86/x86
Message-ID:  <55CF390F.5010407@FreeBSD.org>
In-Reply-To: <201508142008.t7EK8Hkt037329@repo.freebsd.org>
References:  <201508142008.t7EK8Hkt037329@repo.freebsd.org>

next in thread | previous in thread | raw e-mail | index | archive | help
El 14/08/15 a les 22.08, Jason A. Harmening ha escrit:
> Author: jah
> Date: Fri Aug 14 20:08:16 2015
> New Revision: 286787
> URL: https://svnweb.freebsd.org/changeset/base/286787
> 
> Log:
>   Use pmap_quick_enter_page() to handle bouncing of unmapped buffers in the x86 busdma_bounce implementation.  Also treat user buffers as unmapped.
>   This allows two things:
>   1. Sync'ing bounced maps in non-sleepable contexts.  The physcopy* calls previously used could sleep on sf_buf operations in some cases.
>   2. Sync'ing user buffers outside the context of the owning process

AFAICT this will break the Xen port. physcopy* uses uiomove_fromphys
that on the amd64 port is able to deal with pages outside of the DMAP.
OTOH pmap_quick_enter_page is not able to deal with pages outside of the
DMAP, and will simply panic.

Roger.




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?55CF390F.5010407>