From nobody Fri Feb 13 17:31:39 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BF3D1E6FE54 for ; Fri, 22 Sep 2023 15:19:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232924AbjIVPTr (ORCPT ); Fri, 22 Sep 2023 11:19:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59526 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232775AbjIVPTl (ORCPT ); Fri, 22 Sep 2023 11:19:41 -0400 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 08828100 for ; Fri, 22 Sep 2023 08:19:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1695395974; x=1726931974; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=IXYskJaCLZ+4OaCPYK8RdzCAFgSujuD6QEnWhzftS5U=; b=eMGg+KKdc9qGfN0G1QXJFHu6S1FMiWbDrZFu5W4eE/uE2bkpG7tLL9hQ k2gFtoYSTms6ijf6F4R0aSL/q4v4+1GTtmEiuJJm+g+zoqhYrUf5bzEEn YU34DOTD0JYaCZAXIUCyQrGTbIf6w7HkZw6GVSaJ81UAqWRzOrLKXk5qf YY4PCb/bllfvenYQda43rgoiRHkbU6ROt6qigvvlSc/Tqgxv1Rqqd5o5g 7cD4FEQ3i+ob3EgLcrTyWYYAEzNNaw/MIOx8vp0jRGBM3SAma+sNri6JD ONNT4AqmeMkbkWSJ3fnKzBOm26Mp9Whb2h8VazdoQ7RL0E+YT+o4zeKkB g==; X-IronPort-AV: E=McAfee;i="6600,9927,10841"; a="360235284" X-IronPort-AV: E=Sophos;i="6.03,167,1694761200"; d="scan'208";a="360235284" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Sep 2023 08:19:34 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10841"; a="741133186" X-IronPort-AV: E=Sophos;i="6.03,167,1694761200"; d="scan'208";a="741133186" Received: from cascade.sh.intel.com ([10.239.48.35]) by orsmga007.jf.intel.com with ESMTP; 22 Sep 2023 08:19:32 -0700 From: Jingqi Liu To: iommu@lists.linux.dev, Lu Baolu , Tian Kevin , Joerg Roedel , Will Deacon , Robin Murphy Cc: linux-kernel@vger.kernel.org, Jingqi Liu Subject: [PATCH v2 2/3] iommu/vt-d: debugfs: Create/remove debugfs file per {device, pasid} Date: Fri, 22 Sep 2023 23:16:35 +0800 Message-Id: <20230922151636.77139-3-Jingqi.liu@intel.com> X-Mailer: git-send-email 2.21.3 In-Reply-To: <20230922151636.77139-1-Jingqi.liu@intel.com> References: <20230922151636.77139-1-Jingqi.liu@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Add a debugfs directory per pair of {device, pasid} if the mappings of its page table are created and destroyed by the iommu_map/unmap() interfaces. i.e. /sys/kernel/debug/iommu/intel//. Create a debugfs file in the directory for users to dump the page table corresponding to {device, pasid}. e.g. /sys/kernel/debug/iommu/intel/0000:00:02.0/0/domain_translation_struct. When attaching device without pasid, create a debugfs file with PASID#0, i.e. RID_PASID. When attaching a domain to a pasid of device, create a debugfs file with the specified pasid. When detaching without pasid, remove the directory and file for PASID#0. When detaching with pasid, remove the debugfs directory and file of the specified pasid. Remove the entire debugfs directory of the specified device for releasing device. e.g. /sys/kernel/debug/iommu/intel/0000:00:01.0 Signed-off-by: Jingqi Liu --- drivers/iommu/intel/debugfs.c | 117 ++++++++++++++++++++++++++++++++-- drivers/iommu/intel/iommu.c | 16 +++++ drivers/iommu/intel/iommu.h | 4 ++ 3 files changed, 132 insertions(+), 5 deletions(-) diff --git a/drivers/iommu/intel/debugfs.c b/drivers/iommu/intel/debugfs.c index e2a3c37943a0..9128febba3c6 100644 --- a/drivers/iommu/intel/debugfs.c +++ b/drivers/iommu/intel/debugfs.c @@ -32,6 +32,11 @@ struct iommu_regset { const char *regs; }; =20 +struct show_domain_info { + struct device *dev; + ioasid_t pasid; +}; + #define DEBUG_BUFFER_SIZE 1024 static char debug_buf[DEBUG_BUFFER_SIZE]; =20 @@ -111,6 +116,8 @@ static const struct iommu_regset iommu_regs_64[] =3D { IOMMU_REGSET_ENTRY(VCRSP), }; =20 +static struct dentry *intel_iommu_debug; + static int iommu_regset_show(struct seq_file *m, void *unused) { struct dmar_drhd_unit *drhd; @@ -673,16 +680,12 @@ static const struct file_operations dmar_perf_latency= _fops =3D { =20 void __init intel_iommu_debugfs_init(void) { - struct dentry *intel_iommu_debug =3D debugfs_create_dir("intel", - iommu_debugfs_dir); + intel_iommu_debug =3D debugfs_create_dir("intel", iommu_debugfs_dir); =20 debugfs_create_file("iommu_regset", 0444, intel_iommu_debug, NULL, &iommu_regset_fops); debugfs_create_file("dmar_translation_struct", 0444, intel_iommu_debug, NULL, &dmar_translation_struct_fops); - debugfs_create_file("domain_translation_struct", 0444, - intel_iommu_debug, NULL, - &domain_translation_struct_fops); debugfs_create_file("invalidation_queue", 0444, intel_iommu_debug, NULL, &invalidation_queue_fops); #ifdef CONFIG_IRQ_REMAP @@ -692,3 +695,107 @@ void __init intel_iommu_debugfs_init(void) debugfs_create_file("dmar_perf_latency", 0644, intel_iommu_debug, NULL, &dmar_perf_latency_fops); } + +/* + * Create a debugfs directory per pair of {device, pasid}, + * then create the corresponding debugfs file in this directory + * for user to dump its page table. e.g. + * /sys/kernel/debug/iommu/intel/0000:00:01.0/0/domain_translation_struct + */ +void intel_iommu_debugfs_create_dev_pasid(struct device *dev, u32 pasid) +{ + struct dentry *pasid_dir =3D NULL, *dev_dir =3D NULL; + struct iommu_domain *domain =3D NULL; + struct show_domain_info *sinfo; + char pname[10]; + + if (pasid =3D=3D IOMMU_NO_PASID) { + struct device_domain_info *info =3D dev_iommu_priv_get(dev); + if (!info) + return; + domain =3D &info->domain->domain; + } else + domain =3D iommu_get_domain_for_dev_pasid(dev, pasid, 0); + + /* + * The debugfs only dumps the page tables whose mappings are created + * and destroyed by the iommu_map/unmap() interfaces. Check the + * mapping type of the domain before creating debugfs directory. + */ + if (!domain || !(domain->type & __IOMMU_DOMAIN_PAGING)) + return; + + dev_dir =3D debugfs_lookup(dev_name(dev), intel_iommu_debug); + if (!dev_dir) { + dev_dir =3D debugfs_create_dir(dev_name(dev), intel_iommu_debug); + if (IS_ERR(dev_dir)) + return; + } + + sprintf(pname, "%x", pasid); + pasid_dir =3D debugfs_create_dir(pname, dev_dir); + if (IS_ERR(pasid_dir)) + return; + + sinfo =3D kzalloc(sizeof(*sinfo), GFP_KERNEL); + if (!sinfo) + return; + + sinfo->dev =3D dev; + sinfo->pasid =3D pasid; + + debugfs_create_file("domain_translation_struct", 0444, + pasid_dir, sinfo, + &domain_translation_struct_fops); +} + +/* + * Remove the debugfs directory and file corresponding to each pair of + * {device, pasid}. There're two scenarios that will call this helper: + * 1) Detach the specified device with pasid. + * 2) IOMMU release a device. + */ +void intel_iommu_debugfs_remove_dev_pasid(struct device *dev, u32 pasid) +{ + struct dentry *pasid_dir =3D NULL, *dev_dir =3D NULL; + struct dentry *dentry =3D NULL; + char pname[10]; + + dev_dir =3D debugfs_lookup(dev_name(dev), intel_iommu_debug); + if (!dev_dir) + return; + + /* Check if the entire debugfs directory needs to be removed. */ + if (pasid =3D=3D IOMMU_PASID_INVALID) { + struct list_head *plist; + struct dentry *sub_dentry; + + list_for_each(plist, &(dev_dir->d_subdirs)) { + sub_dentry =3D list_entry(plist, struct dentry, d_child); + if(sub_dentry) { + dentry =3D debugfs_lookup("domain_translation_struct", sub_dentry); + if (!dentry) + continue; + + if (dentry->d_inode->i_private) + kfree(dentry->d_inode->i_private); + } + } + + debugfs_remove_recursive(dev_dir); + } else { /* Remove the directory with specified pasid. */ + sprintf(pname, "%x", pasid); + pasid_dir =3D debugfs_lookup(pname, dev_dir); + if (!pasid_dir) + return; + + dentry =3D debugfs_lookup("domain_translation_struct", pasid_dir); + if (!dentry) + return; + + if (dentry->d_inode->i_private) + kfree(dentry->d_inode->i_private); + + debugfs_remove_recursive(pasid_dir); + } +} diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index dd8ff358867d..8d3c3ef1d0e2 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -2488,6 +2488,8 @@ static int dmar_domain_attach_device(struct dmar_doma= in *domain, =20 iommu_enable_pci_caps(info); =20 + intel_iommu_debugfs_create_dev_pasid(dev, IOMMU_NO_PASID); + return 0; } =20 @@ -3966,6 +3968,9 @@ static void dmar_remove_one_dev_info(struct device *d= ev) =20 domain_detach_iommu(domain, iommu); info->domain =3D NULL; + + /* Remove the entire debugfs directory specified by device. */ + intel_iommu_debugfs_remove_dev_pasid(dev, IOMMU_PASID_INVALID); } =20 /* @@ -3997,6 +4002,12 @@ static void device_block_translation(struct device *= dev) =20 domain_detach_iommu(info->domain, iommu); info->domain =3D NULL; + + /* + * Remove the debugfs directory specified by device and + * RID_PASID pasid. + */ + intel_iommu_debugfs_remove_dev_pasid(dev, IOMMU_NO_PASID); } =20 static int md_domain_init(struct dmar_domain *domain, int guest_width) @@ -4729,6 +4740,9 @@ static void intel_iommu_remove_dev_pasid(struct devic= e *dev, ioasid_t pasid) out_tear_down: intel_pasid_tear_down_entry(iommu, dev, pasid, false); intel_drain_pasid_prq(dev, pasid); + + /* Remove the debugfs directory specified by device and pasid. */ + intel_iommu_debugfs_remove_dev_pasid(dev, pasid); } =20 static int intel_iommu_set_dev_pasid(struct iommu_domain *domain, @@ -4777,6 +4791,8 @@ static int intel_iommu_set_dev_pasid(struct iommu_dom= ain *domain, list_add(&dev_pasid->link_domain, &dmar_domain->dev_pasids); spin_unlock_irqrestore(&dmar_domain->lock, flags); =20 + intel_iommu_debugfs_create_dev_pasid(dev, pasid); + return 0; out_detach_iommu: domain_detach_iommu(dmar_domain, iommu); diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h index c18fb699c87a..250178d8014b 100644 --- a/drivers/iommu/intel/iommu.h +++ b/drivers/iommu/intel/iommu.h @@ -883,8 +883,12 @@ static inline void intel_svm_remove_dev_pasid(struct d= evice *dev, ioasid_t pasid =20 #ifdef CONFIG_INTEL_IOMMU_DEBUGFS void intel_iommu_debugfs_init(void); +void intel_iommu_debugfs_create_dev_pasid(struct device *dev, u32 pasid); +void intel_iommu_debugfs_remove_dev_pasid(struct device *dev, u32 pasid); #else static inline void intel_iommu_debugfs_init(void) {} +void intel_iommu_debugfs_create_dev_pasid(struct device *dev, u32 pasid) {} +void intel_iommu_debugfs_remove_dev_pasid(struct device *dev, u32 pasid) {} #endif /* CONFIG_INTEL_IOMMU_DEBUGFS */ =20 extern const struct attribute_group *intel_iommu_groups[]; --=20 2.21.3