PCI: Fix devfn for VPD access through function 0

commit 9d9240756e63dd87d6cbf5da8b98ceb8f8192b55 upstream.

Commit 932c435caba8 ("PCI: Add dev_flags bit to access VPD through function
0") passes PCI_SLOT(devfn) for the devfn parameter of pci_get_slot().
Generally this works because we're fairly well guaranteed that a PCIe
device is at slot address 0, but for the general case, including
conventional PCI, it's incorrect.  We need to get the slot and then convert
it back into a devfn.

Fixes: 932c435caba8 ("PCI: Add dev_flags bit to access VPD through function 0")
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <helgaas@kernel.org>
Acked-by: Myron Stowe <myron.stowe@redhat.com>
Acked-by: Mark Rustad <mark.d.rustad@intel.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>

diff --git a/drivers/pci/access.c b/drivers/pci/access.c
index 6bc9b12ba42a67312e61749983b142081058f5e3..16a022ee54a6f11f2c27ace85b81c98490eb6a66 100644 (file)
--- a/drivers/pci/access.c
+++ b/drivers/pci/access.c
@@ -362,7 +362,8 @@ static const struct pci_vpd_ops pci_vpd_pci22_ops = {
 static ssize_t pci_vpd_f0_read(struct pci_dev *dev, loff_t pos, size_t count,
                               void *arg)
 {
-       struct pci_dev *tdev = pci_get_slot(dev->bus, PCI_SLOT(dev->devfn));
+       struct pci_dev *tdev = pci_get_slot(dev->bus,
+                                           PCI_DEVFN(PCI_SLOT(dev->devfn), 0));
        ssize_t ret;
 
        if (!tdev)
@@ -376,7 +377,8 @@ static ssize_t pci_vpd_f0_read(struct pci_dev *dev, loff_t pos, size_t count,
 static ssize_t pci_vpd_f0_write(struct pci_dev *dev, loff_t pos, size_t count,
                                const void *arg)
 {
-       struct pci_dev *tdev = pci_get_slot(dev->bus, PCI_SLOT(dev->devfn));
+       struct pci_dev *tdev = pci_get_slot(dev->bus,
+                                           PCI_DEVFN(PCI_SLOT(dev->devfn), 0));
        ssize_t ret;
 
        if (!tdev)
@@ -395,7 +397,8 @@ static const struct pci_vpd_ops pci_vpd_f0_ops = {
 
 static int pci_vpd_f0_dev_check(struct pci_dev *dev)
 {
-       struct pci_dev *tdev = pci_get_slot(dev->bus, PCI_SLOT(dev->devfn));
+       struct pci_dev *tdev = pci_get_slot(dev->bus,
+                                           PCI_DEVFN(PCI_SLOT(dev->devfn), 0));
        int ret = 0;
 
        if (!tdev)