PCI/sysfs: Compile pci-sysfs.c only if CONFIG_SYSFS=y

It is possible to enable CONFIG_PCI but disable CONFIG_SYSFS and for
space-constrained devices such as routers, such a configuration may
actually make sense.

However pci-sysfs.c is compiled even if CONFIG_SYSFS is disabled,
unnecessarily increasing the kernel's size.

To rectify that:

* Move pci_mmap_fits() to mmap.c.  It is not only needed by
  pci-sysfs.c, but also proc.c.

* Move pci_dev_type to probe.c and make it private.  It references
  pci_dev_attr_groups in pci-sysfs.c.  Make that public instead for
  consistency with pci_dev_groups, pcibus_groups and pci_bus_groups,
  which are likewise public and referenced by struct definitions in
  pci-driver.c and probe.c.

* Define pci_dev_groups, pci_dev_attr_groups, pcibus_groups and
  pci_bus_groups to NULL if CONFIG_SYSFS is disabled.  Provide empty
  static inlines for pci_{create,remove}_legacy_files() and
  pci_{create,remove}_sysfs_dev_files().

Result:

vmlinux size is reduced by 122996 bytes in my arm 32-bit test build.

Link: https://lore.kernel.org/r/85ca95ae8e4d57ccf082c5c069b8b21eb141846e.1698668982.git.lukas@wunner.de
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

1 files changed, 1 insertions, 28 deletions

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 2321fdfefd7d..44ed30df08c3 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -1022,29 +1022,6 @@ void pci_remove_legacy_files(struct pci_bus *b)
 #endif /* HAVE_PCI_LEGACY */
 
 #if defined(HAVE_PCI_MMAP) || defined(ARCH_GENERIC_PCI_MMAP_RESOURCE)
-
-int pci_mmap_fits(struct pci_dev *pdev, int resno, struct vm_area_struct *vma,
-		  enum pci_mmap_api mmap_api)
-{
-	unsigned long nr, start, size;
-	resource_size_t pci_start = 0, pci_end;
-
-	if (pci_resource_len(pdev, resno) == 0)
-		return 0;
-	nr = vma_pages(vma);
-	start = vma->vm_pgoff;
-	size = ((pci_resource_len(pdev, resno) - 1) >> PAGE_SHIFT) + 1;
-	if (mmap_api == PCI_MMAP_PROCFS) {
-		pci_resource_to_user(pdev, resno, &pdev->resource[resno],
-				     &pci_start, &pci_end);
-		pci_start >>= PAGE_SHIFT;
-	}
-	if (start >= pci_start && start < pci_start + size &&
-			start + nr <= pci_start + size)
-		return 1;
-	return 0;
-}
-
 /**
  * pci_mmap_resource - map a PCI resource into user memory space
  * @kobj: kobject for mapping
@@ -1660,7 +1637,7 @@ static const struct attribute_group pcie_dev_attr_group = {
 	.is_visible = pcie_dev_attrs_are_visible,
 };
 
-static const struct attribute_group *pci_dev_attr_groups[] = {
+const struct attribute_group *pci_dev_attr_groups[] = {
 	&pci_dev_attr_group,
 	&pci_dev_hp_attr_group,
 #ifdef CONFIG_PCI_IOV
@@ -1677,7 +1654,3 @@ static const struct attribute_group *pci_dev_attr_groups[] = {
 #endif
 	NULL,
 };
-
-const struct device_type pci_dev_type = {
-	.groups = pci_dev_attr_groups,
-};