diff options
| author | Krzysztof Wilczyński <kwilczynski@kernel.org> | 2026-05-08 04:35:43 +0000 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2026-06-23 15:19:09 -0500 |
| commit | c9b4bd6c0839c855b7cc221af0283c1900036fc6 (patch) | |
| tree | 7bc39760d3e451a3c49cf16c8123ea4925d28541 | |
| parent | 2800a911ced1540baa78de7494218aaf1c7dc4fa (diff) | |
PCI/sysfs: Limit BAR resize attribute scope to platforms with PCI mmap
Currently, __resource_resize_store() uses sysfs_remove_groups() and
sysfs_create_groups() on pci_dev_resource_attr_groups to tear down and
recreate the resourceN files after a BAR resize, so the updated BAR sizes
are visible in sysfs.
The resourceN files only exist on platforms that define HAVE_PCI_MMAP or
ARCH_GENERIC_PCI_MMAP_RESOURCE. On platforms that define neither,
pci_dev_resource_attr_groups is NULL and the sysfs_remove_groups() and
sysfs_create_groups() calls in __resource_resize_store() become no-ops.
Resizable BAR (ReBAR) is a PCI Express Extended Capability
(PCI_EXT_CAP_ID_REBAR) that requires PCIe extended config space. Every
PCIe-capable architecture defines HAVE_PCI_MMAP or
ARCH_GENERIC_PCI_MMAP_RESOURCE (via arch headers or the asm-generic/pci.h
fallback). Architectures without either only support conventional PCI and
cannot have any ReBAR-capable devices.
Move the resize show and store helpers, the per-BAR attribute definitions,
and the attribute group behind the existing #ifdef HAVE_PCI_MMAP ||
ARCH_GENERIC_PCI_MMAP_RESOURCE guard, and fold the group reference in
pci_dev_groups[] into the existing #if block.
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Link: https://patch.msgid.link/20260508043543.217179-25-kwilczynski@kernel.org
| -rw-r--r-- | drivers/pci/pci-sysfs.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index 15969930b4d1..d4b5f385a6cd 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -1661,6 +1661,7 @@ static const struct attribute_group pci_dev_reset_method_attr_group = { .is_visible = pci_dev_reset_attr_is_visible, }; +#if defined(HAVE_PCI_MMAP) || defined(ARCH_GENERIC_PCI_MMAP_RESOURCE) static ssize_t __resource_resize_show(struct device *dev, int n, char *buf) { struct pci_dev *pdev = to_pci_dev(dev); @@ -1775,6 +1776,7 @@ static const struct attribute_group pci_dev_resource_resize_attr_group = { .attrs = resource_resize_attrs, .is_visible = resource_resize_attr_is_visible, }; +#endif static struct attribute *pci_dev_dev_attrs[] = { &dev_attr_boot_vga.attr, @@ -1849,8 +1851,8 @@ const struct attribute_group *pci_dev_groups[] = { &pci_dev_resource_io_attr_group, &pci_dev_resource_uc_attr_group, &pci_dev_resource_wc_attr_group, -#endif &pci_dev_resource_resize_attr_group, +#endif &pci_dev_config_attr_group, &pci_dev_rom_attr_group, &pci_dev_reset_attr_group, |