PCI: Convert PCIe capability PCIBIOS errors to errno

The PCI config accessors (pci_read_config_word(), et al) return
PCIBIOS_SUCCESSFUL (zero) or positive error values like
PCIBIOS_FUNC_NOT_SUPPORTED.

The PCIe capability accessors (pcie_capability_read_word(), et al)
similarly return PCIBIOS errors, but some callers assume they return
generic errno values like -EINVAL.

For example, the Myri-10G probe function returns a positive PCIBIOS error
if the pcie_capability_clear_and_set_word() in pcie_set_readrq() fails:

  myri10ge_probe
    status = pcie_set_readrq
      return pcie_capability_clear_and_set_word
    if (status)
      return status

A positive return from a PCI driver probe function would cause a "Driver
probe function unexpectedly returned" warning from local_pci_probe()
instead of the desired probe failure.

Convert PCIBIOS errors to generic errno for all callers of:

  pcie_capability_read_word
  pcie_capability_read_dword
  pcie_capability_write_word
  pcie_capability_write_dword
  pcie_capability_set_word
  pcie_capability_set_dword
  pcie_capability_clear_word
  pcie_capability_clear_dword
  pcie_capability_clear_and_set_word
  pcie_capability_clear_and_set_dword

that check the return code for anything other than zero.

[bhelgaas: commit log, squash together]
Suggested-by: Bjorn Helgaas <bjorn@helgaas.com>
Link: https://lore.kernel.org/r/20200615073225.24061-1-refactormyself@gmail.com
Signed-off-by: Bolarinwa Olayemi Saheed <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 8 insertions, 3 deletions

diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
index 3acf56683915..2dbc1fd2910b 100644
--- a/drivers/pci/pcie/aer.c
+++ b/drivers/pci/pcie/aer.c
@@ -224,20 +224,25 @@ int pcie_aer_is_native(struct pci_dev *dev)
 
 int pci_enable_pcie_error_reporting(struct pci_dev *dev)
 {
+	int rc;
+
 	if (!pcie_aer_is_native(dev))
 		return -EIO;
 
-	return pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_AER_FLAGS);
+	rc = pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_AER_FLAGS);
+	return pcibios_err_to_errno(rc);
 }
 EXPORT_SYMBOL_GPL(pci_enable_pcie_error_reporting);
 
 int pci_disable_pcie_error_reporting(struct pci_dev *dev)
 {
+	int rc;
+
 	if (!pcie_aer_is_native(dev))
 		return -EIO;
 
-	return pcie_capability_clear_word(dev, PCI_EXP_DEVCTL,
-					  PCI_EXP_AER_FLAGS);
+	rc = pcie_capability_clear_word(dev, PCI_EXP_DEVCTL, PCI_EXP_AER_FLAGS);
+	return pcibios_err_to_errno(rc);
 }
 EXPORT_SYMBOL_GPL(pci_disable_pcie_error_reporting);