arm64: PCI: Manage controller-specific data on per-controller basis (093d24a2) · Commits · 戴 / test

Currently we use one shared global acpi_pci_root_ops structure to keep controller-specific ops. We pass its pointer to acpi_pci_root_create() and associate it with a host bridge instance for good. Such a design implies serious drawback. Any potential manipulation on the single system-wide acpi_pci_root_ops leads to kernel crash. The structure content is not really changing even across multiple host bridges creation; thus it was not an issue so far. In preparation for adding ECAM quirks mechanism (where controller-specific PCI ops may be different for each host bridge) allocate new acpi_pci_root_ops and fill in with data for each bridge. Now it is safe to have different controller-specific info. As a consequence free acpi_pci_root_ops when host bridge is released. No functional changes in this patch. Signed-off-by:

Tomasz Nowicki <tn@semihalf.com> Signed-off-by:

Bjorn Helgaas <bhelgaas@google.com> Acked-by:

Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

arch/arm64/kernel/pci.c

+10 −7

Original line number	Diff line number	Diff line
		@@ -168,33 +168,36 @@ static void pci_acpi_generic_release_info(struct acpi_pci_root_info *ci)

		ri = container_of(ci, struct acpi_pci_generic_root_info, common);
		pci_ecam_free(ri->cfg);
		kfree(ci->ops);
		kfree(ri);
		}

		static struct acpi_pci_root_ops acpi_pci_root_ops = {
		.release_info = pci_acpi_generic_release_info,
		};

		/* Interface called from ACPI code to setup PCI host controller */
		struct pci_bus pci_acpi_scan_root(struct acpi_pci_root root)
		{
		int node = acpi_get_node(root->device->handle);
		struct acpi_pci_generic_root_info *ri;
		struct pci_bus bus, child;
		struct acpi_pci_root_ops *root_ops;

		ri = kzalloc_node(sizeof(*ri), GFP_KERNEL, node);
		if (!ri)
		return NULL;

		root_ops = kzalloc_node(sizeof(*root_ops), GFP_KERNEL, node);
		if (!root_ops)
		return NULL;

		ri->cfg = pci_acpi_setup_ecam_mapping(root);
		if (!ri->cfg) {
		kfree(ri);
		kfree(root_ops);
		return NULL;
		}

		acpi_pci_root_ops.pci_ops = &ri->cfg->ops->pci_ops;
		bus = acpi_pci_root_create(root, &acpi_pci_root_ops, &ri->common,
		ri->cfg);
		root_ops->release_info = pci_acpi_generic_release_info;
		root_ops->pci_ops = &ri->cfg->ops->pci_ops;
		bus = acpi_pci_root_create(root, root_ops, &ri->common, ri->cfg);
		if (!bus)
		return NULL;

Admin message