PCI: Make pci_match_one_device() match on ID instead of device

PCI dynamic ID needs to match IDs against a new ID to see if it already
exists. Existing APIs can only match IDs against devices, so the dynamic ID
insertion code creates a temporary device only for matching purposes.
Rename pci_match_one_device() to pci_match_one_id() so it can be used for
this purpose instead; add a pci_id_from_device() helper to make it easy to
convert users.

Similarly, convert pci_match_id() to do_pci_match_id(). But keep the
existing API because there are many users.

Signed-off-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Link: https://patch.msgid.link/20260723-pci_id_fix-v4-7-3580726844e1@garyguo.net

drivers/pci/pci-driver.c

@@ -90,6 +90,27 @@ static void pci_free_dynids(struct pci_driver *drv)
 	spin_unlock(&drv->dynids.lock);
 }
 
+/**
+ * do_pci_match_id - See if a PCI ID matches a given pci_id table
+ * @ids: array of PCI device ID structures to search in
+ * @dev_id: the actual PCI device ID structure to match against.
+ *
+ * Return: the matching pci_device_id structure or %NULL if there is no match.
+ */
+static const struct pci_device_id *
+do_pci_match_id(const struct pci_device_id *ids,
+		const struct pci_device_id *dev_id)
+{
+	if (ids) {
+		while (ids->vendor || ids->subvendor || ids->class_mask) {
+			if (pci_match_one_id(ids, dev_id))
+				return ids;
+			ids++;
+		}
+	}
+	return NULL;
+}
+
 /**
  * pci_match_id - See if a PCI device matches a given pci_id table
  * @ids: array of PCI device ID structures to search in
@@ -105,14 +126,9 @@ static void pci_free_dynids(struct pci_driver *drv)
 const struct pci_device_id *pci_match_id(const struct pci_device_id *ids,
 					 struct pci_dev *dev)
 {
-	if (ids) {
-		while (ids->vendor || ids->subvendor || ids->class_mask) {
-			if (pci_match_one_device(ids, dev))
-				return ids;
-			ids++;
-		}
-	}
-	return NULL;
+	struct pci_device_id dev_id = pci_id_from_device(dev);
+
+	return do_pci_match_id(ids, &dev_id);
 }
 EXPORT_SYMBOL(pci_match_id);
 
@@ -138,6 +154,7 @@ static const struct pci_device_id *pci_match_device(struct pci_driver *drv,
 {
 	struct pci_dynid *dynid;
 	const struct pci_device_id *found_id = NULL, *ids;
+	struct pci_device_id dev_id;
 	int ret;
 
 	/* When driver_override is set, only bind to the matching driver */
@@ -145,10 +162,11 @@ static const struct pci_device_id *pci_match_device(struct pci_driver *drv,
 	if (ret == 0)
 		return NULL;
 
+	dev_id = pci_id_from_device(dev);
 	/* Look at the dynamic ids first, before the static ones */
 	spin_lock(&drv->dynids.lock);
 	list_for_each_entry(dynid, &drv->dynids.list, node) {
-		if (pci_match_one_device(&dynid->id, dev)) {
+		if (pci_match_one_id(&dynid->id, &dev_id)) {
 			found_id = &dynid->id;
 			break;
 		}
@@ -158,7 +176,7 @@ static const struct pci_device_id *pci_match_device(struct pci_driver *drv,
 	if (found_id)
 		return found_id;
 
-	for (ids = drv->id_table; (found_id = pci_match_id(ids, dev));
+	for (ids = drv->id_table; (found_id = do_pci_match_id(ids, &dev_id));
 	     ids = found_id + 1) {
 		/*
 		 * The match table is split based on driver_override.

drivers/pci/pci.h

@@ -442,21 +442,40 @@ static inline int pci_setup_cardbus(char *str) { return -ENOENT; }
 #endif /* CONFIG_CARDBUS */
 
 /**
- * pci_match_one_device - Tell if a PCI device structure has a matching
- *			  PCI device id structure
- * @id: single PCI device id structure to match
- * @dev: the PCI device structure to match against
+ * pci_id_from_device - Obtain a pci_device_id from a PCI device
+ * @dev: the PCI device
  *
- * Returns the matching pci_device_id structure or %NULL if there is no match.
+ * Return: a pci_device_id filled.
+ */
+static inline struct pci_device_id pci_id_from_device(const struct pci_dev *dev)
+{
+	return (struct pci_device_id) {
+		.vendor = dev->vendor,
+		.device = dev->device,
+		.subvendor = dev->subsystem_vendor,
+		.subdevice = dev->subsystem_device,
+		.class = dev->class,
+	};
+}
+
+/**
+ * pci_match_one_id - Tell if a PCI device ID matches a needle PCI device ID
+ * @id: single PCI device id structure to match against (needle)
+ * @dev_id: the actual ID from the PCI device
+ *
+ * ID can be retrieved from device using pci_id_from_device().
+ *
+ * Return: the matching pci_device_id structure or %NULL if there is no match.
  */
 static inline const struct pci_device_id *
-pci_match_one_device(const struct pci_device_id *id, const struct pci_dev *dev)
+pci_match_one_id(const struct pci_device_id *id,
+		 const struct pci_device_id *dev_id)
 {
-	if ((id->vendor == PCI_ANY_ID || id->vendor == dev->vendor) &&
-	    (id->device == PCI_ANY_ID || id->device == dev->device) &&
-	    (id->subvendor == PCI_ANY_ID || id->subvendor == dev->subsystem_vendor) &&
-	    (id->subdevice == PCI_ANY_ID || id->subdevice == dev->subsystem_device) &&
-	    !((id->class ^ dev->class) & id->class_mask))
+	if ((id->vendor == PCI_ANY_ID || id->vendor == dev_id->vendor) &&
+	    (id->device == PCI_ANY_ID || id->device == dev_id->device) &&
+	    (id->subvendor == PCI_ANY_ID || id->subvendor == dev_id->subvendor) &&
+	    (id->subdevice == PCI_ANY_ID || id->subdevice == dev_id->subdevice) &&
+	    !((id->class ^ dev_id->class) & id->class_mask))
 		return id;
 	return NULL;
 }

drivers/pci/search.c

@@ -245,8 +245,10 @@ static int match_pci_dev_by_id(struct device *dev, const void *data)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
 	const struct pci_device_id *id = data;
+	struct pci_device_id dev_id;
 
-	if (pci_match_one_device(id, pdev))
+	dev_id = pci_id_from_device(pdev);
+	if (pci_match_one_id(id, &dev_id))
 		return 1;
 	return 0;
 }
@@ -416,9 +418,9 @@ EXPORT_SYMBOL(pci_get_class);
  * @class: search for a PCI device with this base class code
  * @from: Previous PCI device found in search, or %NULL for new search.
  *
- * Iterates through the list of known PCI devices. If a PCI device is found
+ * Iterate through the list of known PCI devices. If a PCI device is found
  * with a matching base class code, the reference count to the device is
- * incremented. See pci_match_one_device() to figure out how does this works.
+ * incremented. See pci_match_one_id() to figure out how this works.
  * A new search is initiated by passing %NULL as the @from argument.
  * Otherwise if @from is not %NULL, searches continue from next device on the
  * global list. The reference count for @from is always decremented if it is