From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from g4t3427.houston.hp.com ([15.201.208.55]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Y2z7M-0000Rr-TF for kexec@lists.infradead.org; Mon, 22 Dec 2014 09:17:33 +0000 From: "Li, Zhen-Hua" 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> In-Reply-To: <1419239729-26529-1-git-send-email-zhen-hual@hp.com> References: <1419239729-26529-1-git-send-email-zhen-hual@hp.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: dwmw2@infradead.org, indou.takao@jp.fujitsu.com, bhe@redhat.com, joro@8bytes.org, vgoyal@redhat.com, dyoung@redhat.com Cc: jerry.hoemann@hp.com, tom.vaden@hp.com, linux-pci@vger.kernel.org, kexec@lists.infradead.org, iommu@lists.linux-foundation.org, lisa.mitchell@hp.com, linux-kernel@vger.kernel.org, alex.williamson@redhat.com, zhen-hual@hp.com, ddutile@redhat.com, doug.hatch@hp.com, ishii.hironobu@jp.fujitsu.com, bhelgaas@google.com, billsumnerlinux@gmail.com, li.zhang6@hp.com 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 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec