Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753560Ab3JRMZA (ORCPT ); Fri, 18 Oct 2013 08:25:00 -0400 Received: from smtp02.citrix.com ([66.165.176.63]:60224 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752773Ab3JRMY7 (ORCPT ); Fri, 18 Oct 2013 08:24:59 -0400 X-IronPort-AV: E=Sophos;i="4.93,522,1378857600"; d="scan'208";a="62259004" Date: Fri, 18 Oct 2013 13:23:59 +0100 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: Stefano Stabellini CC: , , , , Ian Campbell , Catalin Marinas , Subject: Re: [PATCH v8 16/19] arm,arm64: do not always merge biovec if we are running on Xen In-Reply-To: <1382031814-8782-16-git-send-email-stefano.stabellini@eu.citrix.com> Message-ID: References: <1382031814-8782-16-git-send-email-stefano.stabellini@eu.citrix.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" X-DLP: MIA2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2920 Lines: 88 Russell, Catalin, are you OK with this patch? It shouldn't have any impact when running on native, only on Xen. On Thu, 17 Oct 2013, Stefano Stabellini wrote: > This is similar to what it is done on X86: biovecs are prevented from merging > otherwise every dma requests would be forced to bounce on the swiotlb buffer. > > Signed-off-by: Stefano Stabellini > > > Changes in v7: > - remove the extra autotranslate check in biomerge.c. > --- > arch/arm/include/asm/io.h | 8 ++++++++ > arch/arm64/include/asm/io.h | 9 +++++++++ > 2 files changed, 17 insertions(+), 0 deletions(-) > > diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h > index d070741..c45effc 100644 > --- a/arch/arm/include/asm/io.h > +++ b/arch/arm/include/asm/io.h > @@ -24,9 +24,11 @@ > #ifdef __KERNEL__ > > #include > +#include > #include > #include > #include > +#include > > /* > * ISA I/O bus memory addresses are 1:1 with the physical address. > @@ -372,6 +374,12 @@ extern void pci_iounmap(struct pci_dev *dev, void __iomem *addr); > #define BIOVEC_MERGEABLE(vec1, vec2) \ > ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2))) > > +extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1, > + const struct bio_vec *vec2); > +#define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \ > + (__BIOVEC_PHYS_MERGEABLE(vec1, vec2) && \ > + (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2))) > + > #ifdef CONFIG_MMU > #define ARCH_HAS_VALID_PHYS_ADDR_RANGE > extern int valid_phys_addr_range(phys_addr_t addr, size_t size); > diff --git a/arch/arm64/include/asm/io.h b/arch/arm64/include/asm/io.h > index 1d12f89..c163287b 100644 > --- a/arch/arm64/include/asm/io.h > +++ b/arch/arm64/include/asm/io.h > @@ -22,11 +22,14 @@ > #ifdef __KERNEL__ > > #include > +#include > > #include > #include > #include > > +#include > + > /* > * Generic IO read/write. These perform native-endian accesses. > */ > @@ -263,5 +266,11 @@ extern int devmem_is_allowed(unsigned long pfn); > */ > #define xlate_dev_kmem_ptr(p) p > > +extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1, > + const struct bio_vec *vec2); > +#define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \ > + (__BIOVEC_PHYS_MERGEABLE(vec1, vec2) && \ > + (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2))) > + > #endif /* __KERNEL__ */ > #endif /* __ASM_IO_H */ > -- > 1.7.2.5 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/