PCI: Use PCI_SET_ERROR_RESPONSE() for disconnected devices

A config read from a PCI device that doesn't exist or doesn't respond
causes a PCI error. There's no real data to return to satisfy the CPU read,
so most hardware fabricates ~0 data.

Use PCI_SET_ERROR_RESPONSE() to set the error response when we think the
device has already been disconnected.

This helps unify PCI error response checking and make error checks
consistent and easier to find.

Link: https://lore.kernel.org/r/29db0a6874716db80757e4e3cdd03562f13eb0cb.1637243717.git.naveennaidu479@gmail.com
Signed-off-by: Naveen Naidu <naveennaidu479@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

diff --git a/drivers/pci/access.c b/drivers/pci/access.c
index eac0765d8bedcfe607b318c425d93836145abbf9..e1add90494ec944280e2c57456a845de9a5c480d 100644 (file)
--- a/drivers/pci/access.c
+++ b/drivers/pci/access.c
@@ -529,7 +529,7 @@ EXPORT_SYMBOL(pcie_capability_clear_and_set_dword);
 int pci_read_config_byte(const struct pci_dev *dev, int where, u8 *val)
 {
        if (pci_dev_is_disconnected(dev)) {
-               *val = ~0;
+               PCI_SET_ERROR_RESPONSE(val);
                return PCIBIOS_DEVICE_NOT_FOUND;
        }
        return pci_bus_read_config_byte(dev->bus, dev->devfn, where, val);
@@ -539,7 +539,7 @@ EXPORT_SYMBOL(pci_read_config_byte);
 int pci_read_config_word(const struct pci_dev *dev, int where, u16 *val)
 {
        if (pci_dev_is_disconnected(dev)) {
-               *val = ~0;
+               PCI_SET_ERROR_RESPONSE(val);
                return PCIBIOS_DEVICE_NOT_FOUND;
        }
        return pci_bus_read_config_word(dev->bus, dev->devfn, where, val);
@@ -550,7 +550,7 @@ int pci_read_config_dword(const struct pci_dev *dev, int where,
                                        u32 *val)
 {
        if (pci_dev_is_disconnected(dev)) {
-               *val = ~0;
+               PCI_SET_ERROR_RESPONSE(val);
                return PCIBIOS_DEVICE_NOT_FOUND;
        }
        return pci_bus_read_config_dword(dev->bus, dev->devfn, where, val);