From owner-svn-src-all@FreeBSD.ORG Fri Jan 14 04:20:29 2011 Return-Path: Delivered-To: svn-src-all@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id C2F0B106564A; Fri, 14 Jan 2011 04:20:29 +0000 (UTC) (envelope-from imp@bsdimp.com) Received: from harmony.bsdimp.com (bsdimp.com [199.45.160.85]) by mx1.freebsd.org (Postfix) with ESMTP id 7F59B8FC12; Fri, 14 Jan 2011 04:20:29 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by harmony.bsdimp.com (8.14.3/8.14.1) with ESMTP id p0DMClW3090013; Thu, 13 Jan 2011 15:12:50 -0700 (MST) (envelope-from imp@bsdimp.com) Message-ID: <4D2F78DF.1090106@bsdimp.com> Date: Thu, 13 Jan 2011 15:12:47 -0700 From: Warner Losh User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-US; rv:1.9.2.12) Gecko/20101029 Thunderbird/3.1.6 MIME-Version: 1.0 To: Bruce Evans References: <201101122108.p0CL8o3Q012038@svn.freebsd.org> <201101121621.30371.jhb@freebsd.org> <20110113104728.L1003@besplex.bde.org> In-Reply-To: <20110113104728.L1003@besplex.bde.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: svn-src-head@FreeBSD.org, Matthew D Fleming , svn-src-all@FreeBSD.org, src-committers@FreeBSD.org, John Baldwin Subject: Re: svn commit: r217330 - head/sys/x86/x86 X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 14 Jan 2011 04:20:29 -0000 On 01/12/2011 17:06, Bruce Evans wrote: > On Wed, 12 Jan 2011, John Baldwin wrote: > >>> Log: >>> Fix a brain fart. Since this file is shared between i386 and >>> amd64, a >>> bus_size_t may be 32 or 64 bits. Change the bounce_zone alignment >>> field >>> to explicitly be 32 bits, as I can't really imagine a DMA device that >>> needs anything close to 2GB alignment of data. >> >> Hmm, we do have devices with 4GB boundaries though. I think I'd >> prefer it if >> you instead if you did this: >> >> #if defined(amd64) || defined(PAE) >> #define SYSCTL_ADD_BUS_SIZE_T SYSCTL_ADD_UQUAD >> #else >> #define SYSCTL_ADD_BUS_SIZE_T SYSCTL_ADD_UINT >> #endif >> >> and then just used SYSCTL_ADD_BUS_SIZE_T() in the code so we could >> let the >> members in the bounce zone retain the same types passed to >> bus_dma_tag_create(). > > U_LONG should work on all arches. malloc(9) still uses u_long instead > of size_t. This works for scalars even on the recently removed i386's > with 32-bit longs where u_long is larger than size_t, since larger is > a fail-safe direction. This fails for pointers. Newer parts of malloc() > and uma are broken unless u_long is the same as uintptr_t, since they > cast pointers to u_long. This direction is fail-safe too, but gcc warns > about it. u_long doesn't work for N32. There, the pointers may only be 32-bit, but PAs ar 64-bit. Longs are only 32-bits. Warner > > uquad_t should never be used, like unsigned long long. Similarly for > signed types. Perhaps it could be removed in sysctl interfaces first. > > Bruce > > >