From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754544Ab3LCTmt (ORCPT ); Tue, 3 Dec 2013 14:42:49 -0500 Received: from g1t0028.austin.hp.com ([15.216.28.35]:41668 "EHLO g1t0028.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753548Ab3LCTmo (ORCPT ); Tue, 3 Dec 2013 14:42:44 -0500 From: Bill Sumner To: dwmw2@infradead.org, indou.takao@jp.fujitsu.com, bhe@redhat.com Cc: iommu@lists.linux-foundation.org, kexec@lists.infradead.org, alex.williamson@redhat.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, ddutile@redhat.com, ishii.hironobu@jp.fujitsu.com, bhelgaas@google.com, bill.sumner@hp.com, doug.hatch@hp.com Subject: [PATCH 1/6] Crashdump-Accepting-Active-IOMMU-Flags-and-Prototypes Date: Tue, 3 Dec 2013 12:41:29 -0700 Message-Id: <1386099694-4190-2-git-send-email-bill.sumner@hp.com> X-Mailer: git-send-email 1.7.11.3 In-Reply-To: <1386099694-4190-1-git-send-email-bill.sumner@hp.com> References: <1386099694-4190-1-git-send-email-bill.sumner@hp.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Signed-off-by: Bill Sumner --- drivers/iommu/intel-iommu.c | 75 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 75 insertions(+) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 15e9b57..a0e8a76 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -48,6 +48,7 @@ #include "irq_remapping.h" #include "pci.h" +#include #define ROOT_SIZE VTD_PAGE_SIZE #define CONTEXT_SIZE VTD_PAGE_SIZE @@ -164,6 +165,80 @@ static inline unsigned long virt_to_dma_pfn(void *p) return page_to_dma_pfn(virt_to_page(p)); } +#ifdef CONFIG_CRASH_DUMP +/* =================================================================== + * Crashdump Accepting Active IOMMU + * Enhances the crashdump kernel to deal with an active iommu + * and legacy DMA from the (old) panic'd 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. + * + * This code: + * 1. accepts the iommu hardware in an active state from the old kernel, + * 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. + * ------------------------------------------------------------------- + */ + +/* Flags for Crashdump Accepting Active IOMMU */ + +static int crashdump_accepting_active_iommu; /* activate this feature */ +static int intel_iommu_translation_tables_are_mapped; /* table copy done */ + +static struct { /* run-time pr_debug() flags */ + unsigned in_crashdump:1; /* if crashdump_accepting_active_iommu */ + unsigned domain_get:1; /* pr_debug in domain_get* functions */ + unsigned copy_page_table:1; /* enter/leave copy_page_table() */ + unsigned copy_page_addr:1; /* enter/leave copy_page_addr() */ + unsigned addr_ranges:1; /* accumulated addr ranges */ + unsigned reserved_ranges:1; /* accumulated addr ranges reserved */ + unsigned page_addr:1; /* adr(each page table) */ + unsigned enter_oldcopy:1; /* enter oldcopy() parameters */ + unsigned leave_oldcopy:1; /* leave oldcopy() parameters */ +} pr_dbg = { /* Enable flags below here */ + .in_crashdump = 1, + .domain_get = 1, + .copy_page_table = 1, + .copy_page_addr = 0, + .addr_ranges = 0, + .reserved_ranges = 0, + .page_addr = 0, + .enter_oldcopy = 0, + .leave_oldcopy = 0, +}; + +/* Prototypes of interface functions for Crashdump Accepting Active IOMMU */ + +static int +copy_intel_iommu_translation_tables(struct dmar_drhd_unit *drhd, + struct root_entry **root_old_p, struct root_entry **root_new_p); + +static int +domain_get_did_from_old_kernel(struct intel_iommu *iommu, struct pci_dev *pdev); + +static int +domain_get_gaw_from_old_kernel(struct intel_iommu *iommu, struct pci_dev *pdev); + +static u64 +domain_get_pgd_from_old_kernel(struct intel_iommu *iommu, struct pci_dev *pdev); + +static void +domain_get_ranges_from_old_kernel(struct dmar_domain *domain, + struct intel_iommu *iommu, struct pci_dev *pdev); +static int +intel_iommu_get_dids_from_old_kernel(struct intel_iommu *iommu); + +/* Debug-print functions for Crashdump Accepting Active IOMMU */ + +static void +print_intel_iommu_registers(struct dmar_drhd_unit *drhd); +#endif /* CONFIG_CRASH_DUMP */ + + /* global iommu list, set NULL for ignored DMAR units */ static struct intel_iommu **g_iommus; -- Bill Sumner