From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from g4t3425.houston.hp.com ([15.201.208.53]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1XgURW-0007Q6-2t for kexec@lists.infradead.org; Tue, 21 Oct 2014 08:05:22 +0000 From: "Li, Zhen-Hua" Subject: [PATCH 2/5] iommu/vt-d: Items required for kdump Date: Tue, 21 Oct 2014 16:04:16 +0800 Message-Id: <1413878659-1383-3-git-send-email-zhen-hual@hp.com> In-Reply-To: <1413878659-1383-1-git-send-email-zhen-hual@hp.com> References: <1413878659-1383-1-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, "Li, Zhen-Hua" , ddutile@redhat.com, doug.hatch@hp.com, ishii.hironobu@jp.fujitsu.com, bhelgaas@google.com, li.zhang6@hp.com Add structure type domain_values_entry used for kdump; Add context functions needed for kdump. Bill Sumner: Original version; Li, Zhenhua: Changed the name of new functions, make them consistent with current context get/set functions. Signed-off-by: Bill Sumner Signed-off-by: Li, Zhen-Hua --- drivers/iommu/intel-iommu.c | 69 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 1c7350d..99fe408 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -207,6 +207,15 @@ get_context_addr_from_root(struct root_entry *root) NULL); } +static inline struct context_entry * +get_context_phys_from_root(struct root_entry *root) +{ + return (struct context_entry *) + (root_present(root) ? (void *) (root->val & VTD_PAGE_MASK) + : NULL); +} + + /* * low 64 bits: * 0: present @@ -227,6 +236,32 @@ static inline bool context_present(struct context_entry *context) { return (context->lo & 1); } + +static inline int context_fault_enable(struct context_entry *c) +{ + return((c->lo >> 1) & 0x1); +} + +static inline int context_translation_type(struct context_entry *c) +{ + return((c->lo >> 2) & 0x3); +} + +static inline u64 context_address_root(struct context_entry *c) +{ + return((c->lo >> VTD_PAGE_SHIFT)); +} + +static inline int context_address_width(struct context_entry *c) +{ + return((c->hi >> 0) & 0x7); +} + +static inline int context_domain_id(struct context_entry *c) +{ + return((c->hi >> 8) & 0xffff); +} + static inline void context_set_present(struct context_entry *context) { context->lo |= 1; @@ -311,6 +346,40 @@ static inline int first_pte_in_page(struct dma_pte *pte) return !((unsigned long)pte & ~VTD_PAGE_MASK); } + +#ifdef CONFIG_CRASH_DUMP +/* + * Fix Crashdump failure caused by leftover DMA through a hardware IOMMU + * + * Fixes the crashdump kernel to deal with an active iommu and legacy + * DMA from the (old) panicked kernel in a manner similar to how legacy + * DMA is handled when no hardware iommu was in use by the old kernel -- + * allow the legacy DMA to continue into its current buffers. + * + * In the crashdump kernel, this code: + * 1. skips disabling the IOMMU's translating of IO Virtual Addresses (IOVA) + * 2. leaves the current translations in-place so that legacy DMA will + * continue to use its current buffers, + * 3. allocates to the device drivers in the crashdump kernel + * portions of the iova address ranges that are different + * from the iova address ranges that were being used by the old kernel + * at the time of the panic. + * + */ + +struct domain_values_entry { + struct list_head link; /* link entries into a list */ + struct iova_domain iovad; /* iova's that belong to this domain */ + struct dma_pte *pgd; /* virtual address */ + int did; /* domain id */ + int gaw; /* max guest address width */ + int iommu_superpage; /* Level of superpages supported: + 0 == 4KiB (no superpages), 1 == 2MiB, + 2 == 1GiB, 3 == 512GiB, 4 == 1TiB */ +}; + +#endif /* CONFIG_CRASH_DUMP */ + /* * This domain is a statically identity mapping domain. * 1. This domain creats a static 1:1 mapping to all usable memory. -- 2.0.0-rc0 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec