From patchwork Wed Jan 7 04:04:26 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Zhen-Hua" X-Patchwork-Id: 425930 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 6B323140082 for ; Wed, 7 Jan 2015 15:08:56 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757508AbbAGEIl (ORCPT ); Tue, 6 Jan 2015 23:08:41 -0500 Received: from g4t3426.houston.hp.com ([15.201.208.54]:50909 "EHLO g4t3426.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755917AbbAGEGC (ORCPT ); Tue, 6 Jan 2015 23:06:02 -0500 Received: from g9t2301.houston.hp.com (g9t2301.houston.hp.com [16.216.185.78]) by g4t3426.houston.hp.com (Postfix) with ESMTP id AFFC180; Wed, 7 Jan 2015 04:06:01 +0000 (UTC) Received: from piepie.asiapacific.hpqcorp.net (unknown [16.187.246.229]) by g9t2301.houston.hp.com (Postfix) with ESMTP id 8DD9872; Wed, 7 Jan 2015 04:05:56 +0000 (UTC) From: "Li, Zhen-Hua" To: , , , , , Cc: , , , , , , , , , , , , , , , Subject: [PATCH v7 02/10] iommu/vt-d: Items required for kdump Date: Wed, 7 Jan 2015 12:04:26 +0800 Message-Id: <1420603474-4235-3-git-send-email-zhen-hual@hp.com> X-Mailer: git-send-email 2.0.0-rc0 In-Reply-To: <1420603474-4235-1-git-send-email-zhen-hual@hp.com> References: <1420603474-4235-1-git-send-email-zhen-hual@hp.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Add structure type domain_values_entry used for kdump; Add context entry 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 | 70 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 2dc6250..5ce2850 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -40,6 +40,7 @@ #include #include #include +#include #include #include #include @@ -208,6 +209,12 @@ get_context_addr_from_root(struct root_entry *root) NULL); } +static inline unsigned long +get_context_phys_from_root(struct root_entry *root) +{ + return root_present(root) ? (root->val & VTD_PAGE_MASK) : 0; +} + /* * low 64 bits: * 0: present @@ -228,6 +235,32 @@ 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; @@ -313,6 +346,43 @@ 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. Do not re-enable IOMMU's translating. + * 3. In kdump kernel, use the old root entry table. + * 4. Leaves the current translations in-place so that legacy DMA will + * continue to use its current buffers. + * 5. 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.