Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752933AbaDOXM3 (ORCPT ); Tue, 15 Apr 2014 19:12:29 -0400 Received: from g4t3427.houston.hp.com ([15.201.208.55]:49995 "EHLO g4t3427.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751748AbaDOXJd (ORCPT ); Tue, 15 Apr 2014 19:09:33 -0400 From: Bill Sumner To: dwmw2@infradead.org, indou.takao@jp.fujitsu.com, bhe@redhat.com, joro@8bytes.org 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, zhenhua@hp.com Subject: [PATCH 5/8] Add new definitions & prototypes to intel-iommu-private.h Date: Tue, 15 Apr 2014 17:09:06 -0600 Message-Id: <1397603349-30930-6-git-send-email-bill.sumner@hp.com> X-Mailer: git-send-email 1.7.11.3 In-Reply-To: <1397603349-30930-1-git-send-email-bill.sumner@hp.com> References: <1397603349-30930-1-git-send-email-bill.sumner@hp.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Items needed for fixing crashdump. Signed-off-by: Bill Sumner --- drivers/iommu/intel-iommu-private.h | 92 +++++++++++++++++++++++++++++++++++++ 1 file changed, 92 insertions(+) diff --git a/drivers/iommu/intel-iommu-private.h b/drivers/iommu/intel-iommu-private.h index 73dabec..b436cd8 100644 --- a/drivers/iommu/intel-iommu-private.h +++ b/drivers/iommu/intel-iommu-private.h @@ -349,3 +349,95 @@ static inline void free_pgtable_page(void *vaddr) free_page((unsigned long)vaddr); } +#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 */ +}; + + + +/* ------------------------------------------------------------------------ + * Prototypes of interface functions + * ------------------------------------------------------------------------ + */ + +extern int +intel_iommu_copy_translation_tables(struct dmar_drhd_unit *drhd, + struct root_entry **root_old_p, struct root_entry **root_new_p, + int g_num_of_iommus); + +extern int +intel_iommu_get_dids_from_old_kernel(struct intel_iommu *iommu); + +extern struct domain_values_entry * +intel_iommu_did_to_domain_values_entry(int did, struct intel_iommu *iommu); + + +/* ------------------------------------------------------------------------ + * Utility functions for accessing the iommu Translation Tables + * ------------------------------------------------------------------------ + */ + +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); +} + +static inline int +context_get_p(struct context_entry *c) {return((c->lo >> 0) & 0x1); } + +static inline int +context_get_fpdi(struct context_entry *c) {return((c->lo >> 1) & 0x1); } + +static inline int +context_get_t(struct context_entry *c) {return((c->lo >> 2) & 0x3); } + +static inline u64 +context_get_asr(struct context_entry *c) {return((c->lo >> 12)); } + +static inline int +context_get_aw(struct context_entry *c) {return((c->hi >> 0) & 0x7); } + +static inline int +context_get_aval(struct context_entry *c) {return((c->hi >> 3) & 0xf); } + +static inline int +context_get_did(struct context_entry *c) {return((c->hi >> 8) & 0xffff); } + +static inline void +context_put_asr(struct context_entry *c, unsigned long asr) +{ + c->lo &= (~VTD_PAGE_MASK); + c->lo |= (asr << VTD_PAGE_SHIFT); +} + +#endif /* CONFIG_CRASH_DUMP */ -- Bill Sumner -- 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/