From nobody Thu Apr 2 17:10:29 2026 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.14]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8068035B645; Fri, 27 Mar 2026 16:23:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.14 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774628606; cv=none; b=s/qK5pUoJNJ9WE3jnNM2yuwiybl2u6dvj6dMGhFuYF8N2p6qaDqzqLVJnl1EvmMn9qiDOFCNCvypw+sigmYzuL2weefi2ql6PxfXYYnLCy2vF1/IXTKi9VV3klzNUUZXNq4VfvRLSrlF9EOpHQpgdJX2bIXDzJqWx0nXp1B3HRU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774628606; c=relaxed/simple; bh=NUtWTN+YsNz/G7G+LqClLzUTJJRtWG7YocdGIa0hACU=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=k78cSMuS/K1kAC/0Mq+4XVl0ROGLzbvUKyUYbQWOPAWiwYJuwqlYcKrhj27wuzaPKizsr2EcveUviMbiUOH3KQkNwS+U/En4cLdltOXbn3Dg2u6so95qQo9JEfmURFZn8syDqEIeso924zq7/E12j+v5TUKOqYTPultzLq86hKw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=Y9u41UTu; arc=none smtp.client-ip=198.175.65.14 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="Y9u41UTu" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1774628605; x=1806164605; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=NUtWTN+YsNz/G7G+LqClLzUTJJRtWG7YocdGIa0hACU=; b=Y9u41UTuVNNg2UhB1hFh8Cnlc8v4lYYYfEESXOeLCq6sian18rCLKk5j MqwAaYvbvjpS9wbhK9gp+KssM7EyatntSL9o0u4mzofVv1zqcvX+tBxCi 1ntTijbyTXt28fooIFPNb8xn6e/DcStXvC6iSVNKHn/RQw8Z7TQsTWQxs 3xmx1Em34Q9mlA0BibVS0Atl20Oi2pZRGwHlK5kncXc3tK4Ossuh/FnIs 9D0ntMnbHH5NHoS/OP7oTaVsv0oHPkX/bhvluujMIUh+eIqg9RvCbBQWd 8xhRk/Hlp6tSgvG5YtXJXXpZQ1PSfq/itnT1bLwLI6HTYFynktn3fgFHV g==; X-CSE-ConnectionGUID: kZD+/wvEQRKWC9dML8Ke9w== X-CSE-MsgGUID: dYSDFBk2SAS0n9bKzYu+yw== X-IronPort-AV: E=McAfee;i="6800,10657,11741"; a="79565584" X-IronPort-AV: E=Sophos;i="6.23,144,1770624000"; d="scan'208";a="79565584" Received: from fmviesa006.fm.intel.com ([10.60.135.146]) by orvoesa106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Mar 2026 09:23:24 -0700 X-CSE-ConnectionGUID: bd88HM/eRFevey5pYm38Xw== X-CSE-MsgGUID: Mgpwnhy6Qc+U3vXdgdZwpg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,144,1770624000"; d="scan'208";a="220516236" Received: from yilunxu-optiplex-7050.sh.intel.com ([10.239.159.165]) by fmviesa006.fm.intel.com with ESMTP; 27 Mar 2026 09:23:21 -0700 From: Xu Yilun To: linux-coco@lists.linux.dev, linux-pci@vger.kernel.org, dan.j.williams@intel.com, x86@kernel.org Cc: chao.gao@intel.com, dave.jiang@intel.com, baolu.lu@linux.intel.com, yilun.xu@linux.intel.com, yilun.xu@intel.com, zhenzhong.duan@intel.com, kvm@vger.kernel.org, rick.p.edgecombe@intel.com, dave.hansen@linux.intel.com, kas@kernel.org, xiaoyao.li@intel.com, vishal.l.verma@intel.com, linux-kernel@vger.kernel.org Subject: [PATCH v2 14/31] PCI/TSM: Report active IDE streams per host bridge Date: Sat, 28 Mar 2026 00:01:15 +0800 Message-Id: <20260327160132.2946114-15-yilun.xu@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20260327160132.2946114-1-yilun.xu@linux.intel.com> References: <20260327160132.2946114-1-yilun.xu@linux.intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Dan Williams The first attempt at an ABI for this failed to account for naming collisions across host bridges: Commit a4438f06b1db ("PCI/TSM: Report active IDE streams") Revive this ABI with a per host bridge link that appears at first stream creation for a given host bridge and disappears after the last stream is removed. For systems with many host bridge objects it allows: ls /sys/class/tsm/tsmN/pci*/stream* ...to find all the host bridges with active streams without first iterating over all host bridges. Yilun notes that is handy to have this short cut [1] and from an administrator perspective it helps with inventory for constrained stream resources. Link: http://lore.kernel.org/aXLtILY85oMU5qlb@yilunxu-OptiPlex-7050 [1] Signed-off-by: Dan Williams --- Documentation/ABI/testing/sysfs-class-tsm | 13 +++ include/linux/pci-ide.h | 2 + include/linux/tsm.h | 3 + drivers/pci/ide.c | 4 + drivers/virt/coco/tsm-core.c | 97 +++++++++++++++++++++++ 5 files changed, 119 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-class-tsm b/Documentation/ABI/= testing/sysfs-class-tsm index 2949468deaf7..1ddb8f357961 100644 --- a/Documentation/ABI/testing/sysfs-class-tsm +++ b/Documentation/ABI/testing/sysfs-class-tsm @@ -7,3 +7,16 @@ Description: signals when the PCI layer is able to support establishment of link encryption and other device-security features coordinated through a platform tsm. + +What: /sys/class/tsm/tsmN/pciDDDD:BB +Contact: linux-pci@vger.kernel.org +Description: + (RO) When a PCIe host bridge has established a secure connection + via a TSM to an endpoint, this symlink appears. It facilitates a + TSM instance scoped view of PCIe Link Encryption and Secure + Session resource consumption across host bridges. The symlink + appears when a host bridge has 1 or more IDE streams established + with this TSM, and disappears when that number returns to 0. See + Documentation/ABI/testing/sysfs-devices-pci-host-bridge for the + description of the pciDDDD:BB/streamH.R.E symlink and the + pciDDDD:BB/available_secure_streams attribute. diff --git a/include/linux/pci-ide.h b/include/linux/pci-ide.h index ae07d9f699c0..381a1bf22a95 100644 --- a/include/linux/pci-ide.h +++ b/include/linux/pci-ide.h @@ -82,6 +82,7 @@ struct pci_ide_regs { * @host_bridge_stream: allocated from host bridge @ide_stream_ida pool * @stream_id: unique Stream ID (within Partner Port pairing) * @name: name of the established Selective IDE Stream in sysfs + * @tsm_dev: For TSM established IDE, the TSM device context * * Negative @stream_id values indicate "uninitialized" on the * expectation that with TSM established IDE the TSM owns the stream_id @@ -93,6 +94,7 @@ struct pci_ide { u8 host_bridge_stream; int stream_id; const char *name; + struct tsm_dev *tsm_dev; }; =20 /* diff --git a/include/linux/tsm.h b/include/linux/tsm.h index 381c53244c83..7f72a154b6b2 100644 --- a/include/linux/tsm.h +++ b/include/linux/tsm.h @@ -123,4 +123,7 @@ int tsm_report_unregister(const struct tsm_report_ops *= ops); struct tsm_dev *tsm_register(struct device *parent, struct pci_tsm_ops *op= s); void tsm_unregister(struct tsm_dev *tsm_dev); struct tsm_dev *find_tsm_dev(int id); +struct pci_ide; +int tsm_ide_stream_register(struct pci_ide *ide); +void tsm_ide_stream_unregister(struct pci_ide *ide); #endif /* __TSM_H */ diff --git a/drivers/pci/ide.c b/drivers/pci/ide.c index be74e8f0ae21..b35e8aba7ecb 100644 --- a/drivers/pci/ide.c +++ b/drivers/pci/ide.c @@ -11,6 +11,7 @@ #include #include #include +#include =20 #include "pci.h" =20 @@ -372,6 +373,9 @@ void pci_ide_stream_release(struct pci_ide *ide) if (ide->partner[PCI_IDE_EP].enable) pci_ide_stream_disable(pdev, ide); =20 + if (ide->tsm_dev) + tsm_ide_stream_unregister(ide); + if (ide->partner[PCI_IDE_RP].setup) pci_ide_stream_teardown(rp, ide); =20 diff --git a/drivers/virt/coco/tsm-core.c b/drivers/virt/coco/tsm-core.c index 98dcf7d836df..ece7cd7ea9d8 100644 --- a/drivers/virt/coco/tsm-core.c +++ b/drivers/virt/coco/tsm-core.c @@ -4,10 +4,12 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt =20 #include +#include #include #include #include #include +#include =20 static struct class *tsm_class; static DEFINE_IDA(tsm_ida); @@ -104,6 +106,100 @@ void tsm_unregister(struct tsm_dev *tsm_dev) } EXPORT_SYMBOL_GPL(tsm_unregister); =20 +static DEFINE_XARRAY(tsm_ide_streams); +static DEFINE_MUTEX(tsm_ide_streams_lock); + +/* tracker for the bridge symlink when the bridge has any streams */ +struct tsm_ide_stream { + struct tsm_dev *tsm_dev; + struct pci_host_bridge *bridge; + struct kref kref; +}; + +static struct tsm_ide_stream *create_streams(struct tsm_dev *tsm_dev, + struct pci_host_bridge *bridge) +{ + int rc; + + struct tsm_ide_stream *streams __free(kfree) =3D + kzalloc(sizeof(*streams), GFP_KERNEL); + if (!streams) + return NULL; + + streams->tsm_dev =3D tsm_dev; + streams->bridge =3D bridge; + kref_init(&streams->kref); + rc =3D xa_insert(&tsm_ide_streams, (unsigned long)bridge, streams, + GFP_KERNEL); + if (rc) + return NULL; + + rc =3D sysfs_create_link(&tsm_dev->dev.kobj, &bridge->dev.kobj, + dev_name(&bridge->dev)); + if (rc) { + xa_erase(&tsm_ide_streams, (unsigned long)bridge); + return NULL; + } + + return no_free_ptr(streams); +} + +int tsm_ide_stream_register(struct pci_ide *ide) +{ + struct tsm_ide_stream *streams; + struct pci_dev *pdev =3D ide->pdev; + struct pci_tsm *tsm =3D pdev->tsm; + struct tsm_dev *tsm_dev =3D tsm->tsm_dev; + struct pci_host_bridge *bridge =3D pci_find_host_bridge(pdev->bus); + + guard(mutex)(&tsm_ide_streams_lock); + streams =3D xa_load(&tsm_ide_streams, (unsigned long)bridge); + if (streams) + kref_get(&streams->kref); + else + streams =3D create_streams(tsm_dev, bridge); + + if (!streams) + return -ENOMEM; + ide->tsm_dev =3D tsm_dev; + + return 0; +} +EXPORT_SYMBOL_GPL(tsm_ide_stream_register); + +static void destroy_streams(struct kref *kref) +{ + struct tsm_ide_stream *streams =3D + container_of(kref, struct tsm_ide_stream, kref); + struct tsm_dev *tsm_dev =3D streams->tsm_dev; + struct pci_host_bridge *bridge =3D streams->bridge; + + lockdep_assert_held(&tsm_ide_streams_lock); + sysfs_remove_link(&tsm_dev->dev.kobj, dev_name(&bridge->dev)); + xa_erase(&tsm_ide_streams, (unsigned long)bridge); + kfree(streams); +} + +void tsm_ide_stream_unregister(struct pci_ide *ide) +{ + struct tsm_ide_stream *streams; + struct tsm_dev *tsm_dev =3D ide->tsm_dev; + struct pci_dev *pdev =3D ide->pdev; + struct pci_host_bridge *bridge =3D pci_find_host_bridge(pdev->bus); + + guard(mutex)(&tsm_ide_streams_lock); + streams =3D xa_load(&tsm_ide_streams, (unsigned long)bridge); + /* catch API abuse */ + if (dev_WARN_ONCE(&tsm_dev->dev, + !streams || streams->tsm_dev !=3D tsm_dev, + "no IDE streams associated with %s\n", + dev_name(&bridge->dev))) + return; + kref_put(&streams->kref, destroy_streams); + ide->tsm_dev =3D NULL; +} +EXPORT_SYMBOL_GPL(tsm_ide_stream_unregister); + static void tsm_release(struct device *dev) { struct tsm_dev *tsm_dev =3D container_of(dev, typeof(*tsm_dev), dev); @@ -126,6 +222,7 @@ module_init(tsm_init) static void __exit tsm_exit(void) { class_destroy(tsm_class); + xa_destroy(&tsm_ide_streams); } module_exit(tsm_exit) =20 --=20 2.25.1