From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 41E53C433E1 for ; Wed, 13 May 2020 22:55:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5067D20659 for ; Wed, 13 May 2020 22:55:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732098AbgEMWz4 (ORCPT ); Wed, 13 May 2020 18:55:56 -0400 Received: from mga17.intel.com ([192.55.52.151]:27069 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731992AbgEMWzw (ORCPT ); Wed, 13 May 2020 18:55:52 -0400 IronPort-SDR: H2FO8/uktPMRmlw4f5lA8/9sN99dlXx/Pz9SgHU0v+AHusePq6Pcix7s/tXFM+7aJDrWnGsrh8 dnlx/0jifcYQ== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 May 2020 15:55:40 -0700 IronPort-SDR: UCh0zLXbqqnmNcmBCNQofwCcKNMGSFJXr70N2cJIeeeqWUDsUTd2JHESo+wTWF5covrMbxBz2b qKSGwe526trQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,389,1583222400"; d="scan'208";a="437682668" Received: from jacob-builder.jf.intel.com ([10.7.199.155]) by orsmga005.jf.intel.com with ESMTP; 13 May 2020 15:55:40 -0700 From: Jacob Pan To: "Lu Baolu" , iommu@lists.linux-foundation.org, LKML , Joerg Roedel , David Woodhouse , Jean-Philippe Brucker , Eric Auger Cc: Yi Liu , "Tian, Kevin" , Raj Ashok , Alex Williamson , "Christoph Hellwig" , Jonathan Cameron , Jacob Pan Subject: [PATCH v13 8/8] iommu/vt-d: Add custom allocator for IOASID Date: Wed, 13 May 2020 16:01:49 -0700 Message-Id: <1589410909-38925-9-git-send-email-jacob.jun.pan@linux.intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1589410909-38925-1-git-send-email-jacob.jun.pan@linux.intel.com> References: <1589410909-38925-1-git-send-email-jacob.jun.pan@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When VT-d driver runs in the guest, PASID allocation must be performed via virtual command interface. This patch registers a custom IOASID allocator which takes precedence over the default XArray based allocator. The resulting IOASID allocation will always come from the host. This ensures that PASID namespace is system- wide. Virtual command registers are used in the guest only, to prevent vmexit cost, we cache the capability and store it during initialization. Signed-off-by: Liu, Yi L Signed-off-by: Jacob Pan Reviewed-by: Eric Auger --- v12 - squashed virtual command register caching patch with its user - reduce indentation --- --- drivers/iommu/dmar.c | 1 + drivers/iommu/intel-iommu.c | 85 +++++++++++++++++++++++++++++++++++++++++++++ include/linux/intel-iommu.h | 7 ++++ 3 files changed, 93 insertions(+) diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c index 34ee8f28555f..66af08ad10fb 100644 --- a/drivers/iommu/dmar.c +++ b/drivers/iommu/dmar.c @@ -963,6 +963,7 @@ static int map_iommu(struct intel_iommu *iommu, u64 phys_addr) warn_invalid_dmar(phys_addr, " returns all ones"); goto unmap; } + iommu->vccap = dmar_readq(iommu->reg + DMAR_VCCAP_REG); /* the registers might be more than one page */ map_size = max_t(int, ecap_max_iotlb_offset(iommu->ecap), diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 17072442ceae..b28a84a9fca3 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -1732,6 +1732,9 @@ static void free_dmar_iommu(struct intel_iommu *iommu) if (ecap_prs(iommu->ecap)) intel_svm_finish_prq(iommu); } + if (ecap_vcs(iommu->ecap) && vccap_pasid(iommu->vccap)) + ioasid_unregister_allocator(&iommu->pasid_allocator); + #endif } @@ -3266,6 +3269,85 @@ static int copy_translation_tables(struct intel_iommu *iommu) return ret; } +#ifdef CONFIG_INTEL_IOMMU_SVM +static ioasid_t intel_vcmd_ioasid_alloc(ioasid_t min, ioasid_t max, void *data) +{ + struct intel_iommu *iommu = data; + ioasid_t ioasid; + + if (!iommu) + return INVALID_IOASID; + /* + * VT-d virtual command interface always uses the full 20 bit + * PASID range. Host can partition guest PASID range based on + * policies but it is out of guest's control. + */ + if (min < PASID_MIN || max > intel_pasid_max_id) + return INVALID_IOASID; + + if (vcmd_alloc_pasid(iommu, &ioasid)) + return INVALID_IOASID; + + return ioasid; +} + +static void intel_vcmd_ioasid_free(ioasid_t ioasid, void *data) +{ + struct intel_iommu *iommu = data; + + if (!iommu) + return; + /* + * Sanity check the ioasid owner is done at upper layer, e.g. VFIO + * We can only free the PASID when all the devices are unbound. + */ + if (ioasid_find(NULL, ioasid, NULL)) { + pr_alert("Cannot free active IOASID %d\n", ioasid); + return; + } + vcmd_free_pasid(iommu, ioasid); +} + +static void register_pasid_allocator(struct intel_iommu *iommu) +{ + /* + * If we are running in the host, no need for custom allocator + * in that PASIDs are allocated from the host system-wide. + */ + if (!cap_caching_mode(iommu->cap)) + return; + + if (!sm_supported(iommu)) { + pr_warn("VT-d Scalable Mode not enabled, no PASID allocation\n"); + return; + } + + /* + * Register a custom PASID allocator if we are running in a guest, + * guest PASID must be obtained via virtual command interface. + * There can be multiple vIOMMUs in each guest but only one allocator + * is active. All vIOMMU allocators will eventually be calling the same + * host allocator. + */ + if (!ecap_vcs(iommu->ecap) || !vccap_pasid(iommu->vccap)) + return; + + pr_info("Register custom PASID allocator\n"); + iommu->pasid_allocator.alloc = intel_vcmd_ioasid_alloc; + iommu->pasid_allocator.free = intel_vcmd_ioasid_free; + iommu->pasid_allocator.pdata = (void *)iommu; + if (ioasid_register_allocator(&iommu->pasid_allocator)) { + pr_warn("Custom PASID allocator failed, scalable mode disabled\n"); + /* + * Disable scalable mode on this IOMMU if there + * is no custom allocator. Mixing SM capable vIOMMU + * and non-SM vIOMMU are not supported. + */ + intel_iommu_sm = 0; + } +} +#endif + static int __init init_dmars(void) { struct dmar_drhd_unit *drhd; @@ -3383,6 +3465,9 @@ static int __init init_dmars(void) */ for_each_active_iommu(iommu, drhd) { iommu_flush_write_buffer(iommu); +#ifdef CONFIG_INTEL_IOMMU_SVM + register_pasid_allocator(iommu); +#endif iommu_set_root_entry(iommu); iommu->flush.flush_context(iommu, 0, 0, 0, DMA_CCMD_GLOBAL_INVL); iommu->flush.flush_iotlb(iommu, 0, 0, 0, DMA_TLB_GLOBAL_FLUSH); diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h index fd641af55494..1d03aa42bf2d 100644 --- a/include/linux/intel-iommu.h +++ b/include/linux/intel-iommu.h @@ -19,6 +19,7 @@ #include #include #include +#include #include #include @@ -195,6 +196,9 @@ #define ecap_max_handle_mask(e) ((e >> 20) & 0xf) #define ecap_sc_support(e) ((e >> 7) & 0x1) /* Snooping Control */ +/* Virtual command interface capability */ +#define vccap_pasid(v) (((v) & DMA_VCS_PAS)) /* PASID allocation */ + /* IOTLB_REG */ #define DMA_TLB_FLUSH_GRANU_OFFSET 60 #define DMA_TLB_GLOBAL_FLUSH (((u64)1) << 60) @@ -288,6 +292,7 @@ /* PRS_REG */ #define DMA_PRS_PPR ((u32)1) +#define DMA_VCS_PAS ((u64)1) #define IOMMU_WAIT_OP(iommu, offset, op, cond, sts) \ do { \ @@ -563,6 +568,7 @@ struct intel_iommu { u64 reg_size; /* size of hw register set */ u64 cap; u64 ecap; + u64 vccap; u32 gcmd; /* Holds TE, EAFL. Don't need SRTP, SFL, WBF */ raw_spinlock_t register_lock; /* protect register handling */ int seq_id; /* sequence id of the iommu */ @@ -583,6 +589,7 @@ struct intel_iommu { #ifdef CONFIG_INTEL_IOMMU_SVM struct page_req_dsc *prq; unsigned char prq_name[16]; /* Name for PRQ interrupt */ + struct ioasid_allocator_ops pasid_allocator; /* Custom allocator for PASIDs */ #endif struct q_inval *qi; /* Queued invalidation info */ u32 *iommu_state; /* Store iommu states between suspend and resume.*/ -- 2.7.4