On 27/8/25 13:51, Dan Williams wrote:
[...]
+static int pci_tsm_connect(struct pci_dev *pdev, struct tsm_dev *tsm_dev)
+{
+ int rc;
+ struct pci_tsm_pf0 *tsm_pf0;
+ const struct pci_tsm_ops *ops = tsm_pci_ops(tsm_dev);
+ struct pci_tsm *pci_tsm __free(tsm_remove) = ops->probe(pdev);
+
+ /* connect() mutually exclusive with subfunction pci_tsm_init() */
+ lockdep_assert_held_write(&pci_tsm_rwsem);
+
+ if (!pci_tsm)
+ return -ENXIO;
+
+ pdev->tsm = pci_tsm;
+ tsm_pf0 = to_pci_tsm_pf0(pdev->tsm);
+
+ /* mutex_intr assumes connect() is always sysfs/user driven */
+ ACQUIRE(mutex_intr, lock)(&tsm_pf0->lock);
+ if ((rc = ACQUIRE_ERR(mutex_intr, &lock)))
+ return rc;
+
+ rc = ops->connect(pdev);
+ if (rc)
+ return rc;
+
+ pdev->tsm = no_free_ptr(pci_tsm);
+
+ /*
+ * Now that the DSM is established, probe() all the potential
+ * dependent functions. Failure to probe a function is not fatal
+ * to connect(), it just disables subsequent security operations
+ * for that function.
+ */
+ pci_tsm_walk_fns(pdev, probe_fn, pdev);
+ return 0;
+}
+
+static ssize_t connect_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct pci_dev *pdev = to_pci_dev(dev);
+ int rc;
+
+ ACQUIRE(rwsem_read_intr, lock)(&pci_tsm_rwsem);
+ if ((rc = ACQUIRE_ERR(rwsem_read_intr, &lock)))
+ return rc;
+
+ if (!pdev->tsm)
+ return sysfs_emit(buf, "\n");
+
+ return sysfs_emit(buf, "%s\n", tsm_name(pdev->tsm->ops->owner));
+}
+
+/* Is @tsm_dev managing physical link / session properties... */
+static bool is_link_tsm(struct tsm_dev *tsm_dev)
+{
+ const struct pci_tsm_ops *ops = tsm_pci_ops(tsm_dev);
+
+ return ops && ops->link_ops.probe;
+}
+
+/* ...or is @tsm_dev managing device security state ? */
+static bool is_devsec_tsm(struct tsm_dev *tsm_dev)
+{
+ const struct pci_tsm_ops *ops = tsm_pci_ops(tsm_dev);
+
+ return ops && ops->devsec_ops.lock;
+}
+
+static ssize_t connect_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct pci_dev *pdev = to_pci_dev(dev);
+ struct tsm_dev *tsm_dev;
+ int rc, id;
+
+ rc = sscanf(buf, "tsm%d\n", &id);
+ if (rc != 1)
+ return -EINVAL;
+
+ ACQUIRE(rwsem_write_kill, lock)(&pci_tsm_rwsem);
+ if ((rc = ACQUIRE_ERR(rwsem_write_kill, &lock)))
+ return rc;
+
+ if (pdev->tsm)
+ return -EBUSY;
In one of my previous RFC, I had an IDE key refresh call and it's been suggested [1] to ditch that and use connect() instead and the clause above prevents it. I am hacking something around this anyway (need to validate the PSP support for it) and may be this may be generalized now rather than later. Thanks,
[1] https://lore.kernel.org/r/66d7a10a4d621_3975294ac@xxxxxxxxxxxxxxxxxxxxxxxxx.notmuch
+
+ tsm_dev = find_tsm_dev(id);
+ if (!is_link_tsm(tsm_dev))
+ return -ENXIO;
+
+ rc = pci_tsm_connect(pdev, tsm_dev);
+ if (rc)
+ return rc;
+ return len;
+}
+static DEVICE_ATTR_RW(connect);
+
--
Alexey
