PCI/TSM: Report active IDE streams

Given that the platform TSM owns IDE Stream ID allocation, report the
active streams via the TSM class device. Establish a symlink from the
class device to the PCI endpoint device consuming the stream, named by
the Stream ID.

Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Alexey Kardashevskiy <aik@amd.com>
Link: https://patch.msgid.link/20251031212902.2256310-10-dan.j.williams@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/Documentation/ABI/testing/sysfs-class-tsm b/Documentation/ABI/testing/sysfs-class-tsm
index 2949468deaf72c5c0eabbf70ab3b6ec7afb62b44..6fc1a5ac6da1af76e88e5be3edf1b7ce4830fe18 100644 (file)
--- a/Documentation/ABI/testing/sysfs-class-tsm
+++ b/Documentation/ABI/testing/sysfs-class-tsm
@@ -7,3 +7,13 @@ 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/streamH.R.E
+Contact:       linux-pci@vger.kernel.org
+Description:
+               (RO) When a host bridge has established a secure connection via
+               the platform TSM, symlink appears. The primary function of this
+               is have a system global review of TSM resource consumption
+               across host bridges. The link points to the endpoint PCI device
+               and matches the same link published by the host bridge. See
+               Documentation/ABI/testing/sysfs-devices-pci-host-bridge.

diff --git a/drivers/pci/ide.c b/drivers/pci/ide.c
index 4ae3872589fc27b23f1b90f60232931145976e82..da5b1acccbb462c50aabc78c149bad354f0e21e9 100644 (file)
--- a/drivers/pci/ide.c
+++ b/drivers/pci/ide.c
@@ -11,6 +11,7 @@
 #include <linux/pci_regs.h>
 #include <linux/slab.h>
 #include <linux/sysfs.h>
+#include <linux/tsm.h>
 
 #include "pci.h"
 
@@ -261,6 +262,9 @@ void pci_ide_stream_release(struct pci_ide *ide)
        if (ide->partner[PCI_IDE_EP].enable)
                pci_ide_stream_disable(pdev, ide);
 
+       if (ide->tsm_dev)
+               tsm_ide_stream_unregister(ide);
+
        if (ide->partner[PCI_IDE_RP].setup)
                pci_ide_stream_teardown(rp, ide);
 

diff --git a/drivers/virt/coco/tsm-core.c b/drivers/virt/coco/tsm-core.c
index 0e705f3067a17fcd4ad20bd09d0ae68d0162643c..f027876a2f198746ad79f90e099b36be0ae581dd 100644 (file)
--- a/drivers/virt/coco/tsm-core.c
+++ b/drivers/virt/coco/tsm-core.c
@@ -4,11 +4,13 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/tsm.h>
+#include <linux/pci.h>
 #include <linux/rwsem.h>
 #include <linux/device.h>
 #include <linux/module.h>
 #include <linux/cleanup.h>
 #include <linux/pci-tsm.h>
+#include <linux/pci-ide.h>
 
 static struct class *tsm_class;
 static DECLARE_RWSEM(tsm_rwsem);
@@ -106,6 +108,32 @@ void tsm_unregister(struct tsm_dev *tsm_dev)
 }
 EXPORT_SYMBOL_GPL(tsm_unregister);
 
+/* must be invoked between tsm_register / tsm_unregister */
+int tsm_ide_stream_register(struct pci_ide *ide)
+{
+       struct pci_dev *pdev = ide->pdev;
+       struct pci_tsm *tsm = pdev->tsm;
+       struct tsm_dev *tsm_dev = tsm->tsm_dev;
+       int rc;
+
+       rc = sysfs_create_link(&tsm_dev->dev.kobj, &pdev->dev.kobj, ide->name);
+       if (rc)
+               return rc;
+
+       ide->tsm_dev = tsm_dev;
+       return 0;
+}
+EXPORT_SYMBOL_GPL(tsm_ide_stream_register);
+
+void tsm_ide_stream_unregister(struct pci_ide *ide)
+{
+       struct tsm_dev *tsm_dev = ide->tsm_dev;
+
+       ide->tsm_dev = NULL;
+       sysfs_remove_link(&tsm_dev->dev.kobj, ide->name);
+}
+EXPORT_SYMBOL_GPL(tsm_ide_stream_unregister);
+
 static void tsm_release(struct device *dev)
 {
        struct tsm_dev *tsm_dev = container_of(dev, typeof(*tsm_dev), dev);

diff --git a/include/linux/pci-ide.h b/include/linux/pci-ide.h
index 85645b0a8620abded423ec7c9a1c4b2b6a07a909..d0f10f3c89fc83363143598ef21787f9f7b62f65 100644 (file)
--- a/include/linux/pci-ide.h
+++ b/include/linux/pci-ide.h
@@ -50,6 +50,7 @@ struct pci_ide_partner {
  * @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
@@ -61,6 +62,7 @@ struct pci_ide {
        u8 host_bridge_stream;
        int stream_id;
        const char *name;
+       struct tsm_dev *tsm_dev;
 };
 
 void pci_ide_set_nr_streams(struct pci_host_bridge *hb, u16 nr);

diff --git a/include/linux/tsm.h b/include/linux/tsm.h
index 22e05b2aac69cf5f435510fb298c969b6776709d..a3b7ab668effffd4132bc03d9eec62c96f31f282 100644 (file)
--- 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 *ops);
 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 */