Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754367AbaLVJRR (ORCPT ); Mon, 22 Dec 2014 04:17:17 -0500 Received: from g4t3427.houston.hp.com ([15.201.208.55]:43762 "EHLO g4t3427.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754169AbaLVJRN (ORCPT ); Mon, 22 Dec 2014 04:17:13 -0500 From: "Li, Zhen-Hua" To: , , , , , Cc: , , , , , , , , , , , , , , Subject: [PATCH 08/10] iommu/vtd: assign new page table for dma_map Date: Mon, 22 Dec 2014 17:15:27 +0800 Message-Id: <1419239729-26529-9-git-send-email-zhen-hual@hp.com> X-Mailer: git-send-email 2.0.0-rc0 In-Reply-To: <1419239729-26529-1-git-send-email-zhen-hual@hp.com> References: <1419239729-26529-1-git-send-email-zhen-hual@hp.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When a device driver issues the first dma_map command for a device, we assign a new and empty page-table, thus removing all mappings from the old kernel for the device. Signed-off-by: Li, Zhen-Hua --- drivers/iommu/intel-iommu.c | 56 ++++++++++++++++++++++++++++++++++++++------- 1 file changed, 48 insertions(+), 8 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 4efed7c..7f8b546 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -44,6 +44,7 @@ #include #include #include +#include #include "irq_remapping.h" @@ -455,6 +456,8 @@ static int copy_root_entry_table(struct intel_iommu *iommu, void *ppap); static int intel_iommu_load_translation_tables(struct dmar_drhd_unit *drhd, int g_num_of_iommus); +static void unmap_device_dma(struct dmar_domain *domain, struct device *dev); + #endif /* CONFIG_CRASH_DUMP */ /* @@ -3199,14 +3202,30 @@ static struct dmar_domain *__get_valid_domain_for_dev(struct device *dev) return NULL; } - /* make sure context mapping is ok */ - if (unlikely(!domain_context_mapped(dev))) { - ret = domain_context_mapping(domain, dev, CONTEXT_TT_MULTI_LEVEL); - if (ret) { - printk(KERN_ERR "Domain context map for %s failed", - dev_name(dev)); - return NULL; - } + /* if in kdump kernel, we need to unmap the mapped dma pages, + * detach this device first. + */ + if (likely(domain_context_mapped(dev))) { +#ifdef CONFIG_CRASH_DUMP + if (is_kdump_kernel()) { + unmap_device_dma(domain, dev); + domain = get_domain_for_dev(dev, + DEFAULT_DOMAIN_ADDRESS_WIDTH); + if (!domain) { + pr_err("Allocating domain for %s failed", + dev_name(dev)); + return NULL; + } + } else +#endif + return domain; + } + + ret = domain_context_mapping(domain, dev, CONTEXT_TT_MULTI_LEVEL); + if (ret) { + pr_err("Domain context map for %s failed", + dev_name(dev)); + return NULL; } return domain; @@ -5687,4 +5706,25 @@ static int intel_iommu_load_translation_tables(struct dmar_drhd_unit *drhd, return 0; } +static void unmap_device_dma(struct dmar_domain *domain, struct device *dev) +{ + struct intel_iommu *iommu; + struct context_entry *ce; + struct iova *iova; + u8 bus, devfn; + phys_addr_t phys_addr; + dma_addr_t dev_addr; + + iommu = device_to_iommu(dev, &bus, &devfn); + ce = device_to_context_entry(iommu, bus, devfn); + phys_addr = context_address_root(ce) << VTD_PAGE_SHIFT; + dev_addr = phys_to_dma(dev, phys_addr); + + iova = find_iova(&domain->iovad, IOVA_PFN(dev_addr)); + if (iova) + intel_unmap(dev, dev_addr); + + domain_remove_one_dev_info(domain, dev); +} + #endif /* CONFIG_CRASH_DUMP */ -- 2.0.0-rc0 -- 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/