PCI/sysfs: Convert "index", "acpi_index", "label" to static attributes

The "label", "index", and "acpi_index" sysfs attributes show firmware label
information about the device.  If the ACPI Device Name _DSM is implemented
for the device, we have:

  label        Device name (optional, may be null)
  acpi_index   Instance number (unique under \_SB scope)

When there is no ACPI _DSM and SMBIOS provides an Onboard Devices structure
for the device, we have:

  label        Reference Designation, e.g., a silkscreen label
  index        Device Type Instance

Previously these attributes were dynamically created either by
pci_bus_add_device() or the pci_sysfs_init() initcall, but since they don't
need to be created or removed dynamically, we can use a static attribute so
the device model takes care of addition and removal automatically.

Convert "label", "index", and "acpi_index" to static attributes.

Presence of the ACPI _DSM (device_has_acpi_name()) determines whether the
ACPI information (label, acpi_index) or the SMBIOS information (label,
index) is visible.

[bhelgaas: commit log, split to separate patch, add "pci_dev_" prefix]
Suggested-by: Oliver O'Halloran <oohall@gmail.com>
Link: https://lore.kernel.org/r/20210416205856.3234481-6-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/pci-label.c

@@ -101,6 +101,9 @@ static umode_t smbios_attr_is_visible(struct kobject *kobj, struct attribute *a,
 	dev = kobj_to_dev(kobj);
 	pdev = to_pci_dev(dev);
 
+	if (device_has_acpi_name(dev))
+		return 0;
+
 	if (!find_smbios_instance_string(pdev, NULL, SMBIOS_ATTR_NONE))
 		return 0;
 
@@ -136,29 +139,10 @@ static struct attribute *smbios_attrs[] = {
 	NULL,
 };
 
-static const struct attribute_group smbios_attr_group = {
+const struct attribute_group pci_dev_smbios_attr_group = {
 	.attrs = smbios_attrs,
 	.is_visible = smbios_attr_is_visible,
 };
-
-static int pci_create_smbiosname_file(struct pci_dev *pdev)
-{
-	return sysfs_create_group(&pdev->dev.kobj, &smbios_attr_group);
-}
-
-static void pci_remove_smbiosname_file(struct pci_dev *pdev)
-{
-	sysfs_remove_group(&pdev->dev.kobj, &smbios_attr_group);
-}
-#else
-static inline int pci_create_smbiosname_file(struct pci_dev *pdev)
-{
-	return -1;
-}
-
-static inline void pci_remove_smbiosname_file(struct pci_dev *pdev)
-{
-}
 #endif
 
 #ifdef CONFIG_ACPI
@@ -253,45 +237,8 @@ static struct attribute *acpi_attrs[] = {
 	NULL,
 };
 
-static const struct attribute_group acpi_attr_group = {
+const struct attribute_group pci_dev_acpi_attr_group = {
 	.attrs = acpi_attrs,
 	.is_visible = acpi_attr_is_visible,
 };
-
-static int pci_create_acpi_index_label_files(struct pci_dev *pdev)
-{
-	return sysfs_create_group(&pdev->dev.kobj, &acpi_attr_group);
-}
-
-static int pci_remove_acpi_index_label_files(struct pci_dev *pdev)
-{
-	sysfs_remove_group(&pdev->dev.kobj, &acpi_attr_group);
-	return 0;
-}
-#else
-static inline int pci_create_acpi_index_label_files(struct pci_dev *pdev)
-{
-	return -1;
-}
-
-static inline int pci_remove_acpi_index_label_files(struct pci_dev *pdev)
-{
-	return -1;
-}
 #endif
-
-void pci_create_firmware_label_files(struct pci_dev *pdev)
-{
-	if (device_has_acpi_name(&pdev->dev))
-		pci_create_acpi_index_label_files(pdev);
-	else
-		pci_create_smbiosname_file(pdev);
-}
-
-void pci_remove_firmware_label_files(struct pci_dev *pdev)
-{
-	if (device_has_acpi_name(&pdev->dev))
-		pci_remove_acpi_index_label_files(pdev);
-	else
-		pci_remove_smbiosname_file(pdev);
-}

drivers/pci/pci-sysfs.c

@@ -1380,18 +1380,10 @@ static const struct attribute_group pci_dev_reset_attr_group = {
 
 int __must_check pci_create_sysfs_dev_files(struct pci_dev *pdev)
 {
-	int retval;
-
 	if (!sysfs_initialized)
 		return -EACCES;
 
-	retval = pci_create_resource_files(pdev);
+	return pci_create_resource_files(pdev);
-	if (retval)
-		return retval;
-
-	pci_create_firmware_label_files(pdev);
-
-	return 0;
 }
 
 /**
@@ -1406,7 +1398,6 @@ void pci_remove_sysfs_dev_files(struct pci_dev *pdev)
 		return;
 
 	pci_remove_resource_files(pdev);
-	pci_remove_firmware_label_files(pdev);
 }
 
 static int __init pci_sysfs_init(void)
@@ -1501,6 +1492,12 @@ const struct attribute_group *pci_dev_groups[] = {
 	&pci_dev_rom_attr_group,
 	&pci_dev_reset_attr_group,
 	&pci_dev_vpd_attr_group,
+#ifdef CONFIG_DMI
+	&pci_dev_smbios_attr_group,
+#endif
+#ifdef CONFIG_ACPI
+	&pci_dev_acpi_attr_group,
+#endif
 	NULL,
 };
 

drivers/pci/pci.h

@@ -21,16 +21,10 @@ bool pcie_cap_has_rtctl(const struct pci_dev *dev);
 
 int pci_create_sysfs_dev_files(struct pci_dev *pdev);
 void pci_remove_sysfs_dev_files(struct pci_dev *pdev);
-#if !defined(CONFIG_DMI) && !defined(CONFIG_ACPI)
-static inline void pci_create_firmware_label_files(struct pci_dev *pdev)
-{ return; }
-static inline void pci_remove_firmware_label_files(struct pci_dev *pdev)
-{ return; }
-#else
-void pci_create_firmware_label_files(struct pci_dev *pdev);
-void pci_remove_firmware_label_files(struct pci_dev *pdev);
-#endif
 void pci_cleanup_rom(struct pci_dev *dev);
+#ifdef CONFIG_DMI
+extern const struct attribute_group pci_dev_smbios_attr_group;
+#endif
 
 enum pci_mmap_api {
 	PCI_MMAP_SYSFS,	/* mmap on /sys/bus/pci/devices/<BDF>/resource<N> */
@@ -695,6 +689,7 @@ static inline int pci_aer_raw_clear_status(struct pci_dev *dev) { return -EINVAL
 
 #ifdef CONFIG_ACPI
 int pci_acpi_program_hp_params(struct pci_dev *dev);
+extern const struct attribute_group pci_dev_acpi_attr_group;
 #else
 static inline int pci_acpi_program_hp_params(struct pci_dev *dev)
 {