From owner-svn-src-stable@FreeBSD.ORG Wed Apr 14 17:01:30 2010 Return-Path: Delivered-To: svn-src-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 28761106566B; Wed, 14 Apr 2010 17:01:30 +0000 (UTC) (envelope-from gibbs@FreeBSD.org) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c]) by mx1.freebsd.org (Postfix) with ESMTP id F1E448FC18; Wed, 14 Apr 2010 17:01:29 +0000 (UTC) Received: from svn.freebsd.org (localhost [127.0.0.1]) by svn.freebsd.org (8.14.3/8.14.3) with ESMTP id o3EH1TrI032037; Wed, 14 Apr 2010 17:01:29 GMT (envelope-from gibbs@svn.freebsd.org) Received: (from gibbs@localhost) by svn.freebsd.org (8.14.3/8.14.3/Submit) id o3EH1TFF032035; Wed, 14 Apr 2010 17:01:29 GMT (envelope-from gibbs@svn.freebsd.org) Message-Id: <201004141701.o3EH1TFF032035@svn.freebsd.org> From: "Justin T. Gibbs" Date: Wed, 14 Apr 2010 17:01:29 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-8@freebsd.org X-SVN-Group: stable-8 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Subject: svn commit: r206610 - stable/8/sys/amd64/amd64 X-BeenThere: svn-src-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: SVN commit messages for all the -stable branches of the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 14 Apr 2010 17:01:30 -0000 Author: gibbs Date: Wed Apr 14 17:01:29 2010 New Revision: 206610 URL: http://svn.freebsd.org/changeset/base/206610 Log: MFC 204214: Enforce stronger bus-dma alignment semantics so bus-dma operates correctly with Xen's blkfront driver. Modified: stable/8/sys/amd64/amd64/busdma_machdep.c Modified: stable/8/sys/amd64/amd64/busdma_machdep.c ============================================================================== --- stable/8/sys/amd64/amd64/busdma_machdep.c Wed Apr 14 16:54:49 2010 (r206609) +++ stable/8/sys/amd64/amd64/busdma_machdep.c Wed Apr 14 17:01:29 2010 (r206610) @@ -239,8 +239,7 @@ bus_dma_tag_create(bus_dma_tag_t parent, newtag->alignment = alignment; newtag->boundary = boundary; newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); - newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + - (PAGE_SIZE - 1); + newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1); newtag->filter = filter; newtag->filterarg = filterarg; newtag->maxsize = maxsize; @@ -605,13 +604,18 @@ _bus_dmamap_load_buffer(bus_dma_tag_t dm vendaddr = (vm_offset_t)buf + buflen; while (vaddr < vendaddr) { + bus_size_t sg_len; + + sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK); if (pmap) paddr = pmap_extract(pmap, vaddr); else paddr = pmap_kextract(vaddr); - if (run_filter(dmat, paddr) != 0) + if (run_filter(dmat, paddr) != 0) { + sg_len = roundup2(sg_len, dmat->alignment); map->pagesneeded++; - vaddr += (PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK)); + } + vaddr += sg_len; } CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); } @@ -644,6 +648,8 @@ _bus_dmamap_load_buffer(bus_dma_tag_t dm bmask = ~(dmat->boundary - 1); for (seg = *segp; buflen > 0 ; ) { + bus_size_t max_sgsize; + /* * Get the physical address for this segment. */ @@ -655,11 +661,15 @@ _bus_dmamap_load_buffer(bus_dma_tag_t dm /* * Compute the segment size, and adjust counts. */ - sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK); - if (sgsize > dmat->maxsegsz) - sgsize = dmat->maxsegsz; - if (buflen < sgsize) - sgsize = buflen; + max_sgsize = MIN(buflen, dmat->maxsegsz); + sgsize = PAGE_SIZE - ((vm_offset_t)curaddr & PAGE_MASK); + if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) { + sgsize = roundup2(sgsize, dmat->alignment); + sgsize = MIN(sgsize, max_sgsize); + curaddr = add_bounce_page(dmat, map, vaddr, sgsize); + } else { + sgsize = MIN(sgsize, max_sgsize); + } /* * Make sure we don't cross any boundaries. @@ -670,9 +680,6 @@ _bus_dmamap_load_buffer(bus_dma_tag_t dm sgsize = (baddr - curaddr); } - if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) - curaddr = add_bounce_page(dmat, map, vaddr, sgsize); - /* * Insert chunk into a segment, coalescing with * previous segment if possible.