From: Krzysztof Wilczyński <kwilczynski@kernel.org>
Date: Fri, 8 May 2026 04:35:31 +0000 (+0000)
Subject: alpha/PCI: Use BAR index in sysfs attr->private instead of resource pointer
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7d9779cb10265f34f405eff1eb50bb955d3f6e7d;p=thirdparty%2Flinux.git

alpha/PCI: Use BAR index in sysfs attr->private instead of resource pointer

Currently, Alpha's pci_create_one_attr() stores a resource pointer in
attr->private, and pci_mmap_resource() loops through all BARs to find
the matching index.

Store the BAR index directly in attr->private and retrieve the resource via
pci_resource_n().  This eliminates the loop and aligns with the convention
used by the generic PCI sysfs code.

The PCI core change was first added in the commit dca40b186b75 ("PCI: Use
BAR index in sysfs attr->private instead of resource pointer").

Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Magnus Lindholm <linmag7@gmail.com>
Tested-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Acked-by: Magnus Lindholm <linmag7@gmail.com>
Link: https://patch.msgid.link/20260508043543.217179-13-kwilczynski@kernel.org
---

diff --git a/arch/alpha/kernel/pci-sysfs.c b/arch/alpha/kernel/pci-sysfs.c
index 2324720c3e83..2330ab84d59c 100644
--- a/arch/alpha/kernel/pci-sysfs.c
+++ b/arch/alpha/kernel/pci-sysfs.c
@@ -69,25 +69,20 @@ static int pci_mmap_resource(struct kobject *kobj,
 			     struct vm_area_struct *vma, int sparse)
 {
 	struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj));
-	struct resource *res = attr->private;
+	int barno = (unsigned long)attr->private;
+	struct resource *res = pci_resource_n(pdev, barno);
 	enum pci_mmap_state mmap_type;
 	struct pci_bus_region bar;
-	int i, ret;
+	int ret;
 
 	ret = security_locked_down(LOCKDOWN_PCI_ACCESS);
 	if (ret)
 		return ret;
 
-	for (i = 0; i < PCI_STD_NUM_BARS; i++)
-		if (res == &pdev->resource[i])
-			break;
-	if (i >= PCI_STD_NUM_BARS)
-		return -ENODEV;
-
 	if (res->flags & IORESOURCE_MEM && iomem_is_exclusive(res->start))
 		return -EINVAL;
 
-	if (!__pci_mmap_fits(pdev, i, vma, sparse))
+	if (!__pci_mmap_fits(pdev, barno, vma, sparse))
 		return -EINVAL;
 
 	pcibios_resource_to_bus(pdev->bus, &bar, res);
@@ -170,7 +165,7 @@ static int pci_create_one_attr(struct pci_dev *pdev, int num, char *name,
 	res_attr->attr.name = name;
 	res_attr->attr.mode = S_IRUSR | S_IWUSR;
 	res_attr->size = sparse ? size << 5 : size;
-	res_attr->private = &pdev->resource[num];
+	res_attr->private = (void *)(unsigned long)num;
 	return sysfs_create_bin_file(&pdev->dev.kobj, res_attr);
 }