From mboxrd@z Thu Jan 1 00:00:00 1970 From: Borislav Petkov Date: Tue, 20 Aug 2019 11:17:53 +0000 Subject: Re: [PATCH 06/11] x86/dma: Get rid of iommu_pass_through Message-Id: <20190820111753.GD31607@zn.tnic> List-Id: References: <20190819132256.14436-1-joro@8bytes.org> <20190819132256.14436-7-joro@8bytes.org> In-Reply-To: <20190819132256.14436-7-joro@8bytes.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Joerg Roedel Cc: corbet@lwn.net, tony.luck@intel.com, fenghua.yu@intel.com, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, linux-doc@vger.kernel.org, linux-ia64@vger.kernel.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Thomas.Lendacky@amd.com, Suravee.Suthikulpanit@amd.com, Joerg Roedel On Mon, Aug 19, 2019 at 03:22:51PM +0200, Joerg Roedel wrote: > From: Joerg Roedel > > This variable has no users anymore. Remove it and tell the > IOMMU code via its new functions about requested DMA modes. > > Signed-off-by: Joerg Roedel > --- > arch/x86/include/asm/iommu.h | 1 - > arch/x86/kernel/pci-dma.c | 20 +++----------------- > 2 files changed, 3 insertions(+), 18 deletions(-) > > diff --git a/arch/x86/include/asm/iommu.h b/arch/x86/include/asm/iommu.h > index baedab8ac538..b91623d521d9 100644 > --- a/arch/x86/include/asm/iommu.h > +++ b/arch/x86/include/asm/iommu.h > @@ -4,7 +4,6 @@ > > extern int force_iommu, no_iommu; > extern int iommu_detected; > -extern int iommu_pass_through; > > /* 10 seconds */ > #define DMAR_OPERATION_TIMEOUT ((cycles_t) tsc_khz*10*1000) > diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c > index f62b498b18fb..fa4352dce491 100644 > --- a/arch/x86/kernel/pci-dma.c > +++ b/arch/x86/kernel/pci-dma.c > @@ -1,6 +1,7 @@ > // SPDX-License-Identifier: GPL-2.0 > #include > #include > +#include > #include > #include > #include > @@ -34,21 +35,6 @@ int no_iommu __read_mostly; > /* Set this to 1 if there is a HW IOMMU in the system */ > int iommu_detected __read_mostly = 0; > > -/* > - * This variable becomes 1 if iommu=pt is passed on the kernel command line. > - * If this variable is 1, IOMMU implementations do no DMA translation for > - * devices and allow every device to access to whole physical memory. This is > - * useful if a user wants to use an IOMMU only for KVM device assignment to > - * guests and not for driver dma translation. > - * It is also possible to disable by default in kernel config, and enable with > - * iommu=nopt at boot time. > - */ > -#ifdef CONFIG_IOMMU_DEFAULT_PASSTHROUGH > -int iommu_pass_through __read_mostly = 1; > -#else > -int iommu_pass_through __read_mostly; > -#endif > - > extern struct iommu_table_entry __iommu_table[], __iommu_table_end[]; > > void __init pci_iommu_alloc(void) > @@ -120,9 +106,9 @@ static __init int iommu_setup(char *p) > swiotlb = 1; > #endif > if (!strncmp(p, "pt", 2)) > - iommu_pass_through = 1; > + iommu_set_default_passthrough(true); > if (!strncmp(p, "nopt", 4)) > - iommu_pass_through = 0; > + iommu_set_default_translated(true); > > gart_parse_options(p); > > -- Reviewed-by: Borislav Petkov -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.