pci: adjust return values for error cases of IOV functions

Changing the return value to -ENOSYS if a device is not physical PCI function. Also have pci_sriov_get_totalvfs() return 0 in the error cae to make the behaviour consistent whether CONFIG_PCI_IOV is enabled or not. Some comment fixes.

Signed-off-by Stefan Assmann <[email protected]>

---
 drivers/pci/iov.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

drivers/pci/iov.c +11 -9

index de8ffac..1fc9942 100644
@@ -324,7 +324,7 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
 
                if (!pdev->is_physfn) {
                        pci_dev_put(pdev);
-                       return -ENODEV;
+                       return -ENOSYS;
                }
 
                rc = sysfs_create_link(&dev->dev.kobj,

@@ -662,7 +662,7 @@ int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
        might_sleep();
 
        if (!dev->is_physfn)
-               return -ENODEV;
+               return -ENOSYS;
 
        return sriov_enable(dev, nr_virtfn);
 }

@@ -722,7 +722,7 @@ EXPORT_SYMBOL_GPL(pci_num_vf);
  * @dev: the PCI device
  *
  * Returns number of VFs belonging to this device that are assigned to a guest.
- * If device is not a physical function returns -ENODEV.
+ * If device is not a physical function returns 0.
  */
 int pci_vfs_assigned(struct pci_dev *dev)
 {

@@ -767,12 +767,15 @@ EXPORT_SYMBOL_GPL(pci_vfs_assigned);
  * device's mutex held.
  *
  * Returns 0 if PF is an SRIOV-capable device and
- * value of numvfs valid. If not a PF with VFS, return -EINVAL;
+ * value of numvfs valid. If not a PF return -ENOSYS;
+ * if numvfs is invalid return -EINVAL;
  * if VFs already enabled, return -EBUSY.
  */
 int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs)
 {
-       if (!dev->is_physfn || (numvfs > dev->sriov->total_VFs))
+       if (!dev->is_physfn)
+               return -ENOSYS;
+       if (numvfs > dev->sriov->total_VFs)
                return -EINVAL;
 
        /* Shouldn't change if VFs already enabled */

@@ -786,17 +789,17 @@ int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs)
 EXPORT_SYMBOL_GPL(pci_sriov_set_totalvfs);
 
 /**
- * pci_sriov_get_totalvfs -- get total VFs supported on this devic3
+ * pci_sriov_get_totalvfs -- get total VFs supported on this device
  * @dev: the PCI PF device
  *
  * For a PCIe device with SRIOV support, return the PCIe
  * SRIOV capability value of TotalVFs or the value of driver_max_VFs
- * if the driver reduced it.  Otherwise, -EINVAL.
+ * if the driver reduced it.  Otherwise 0.
  */
 int pci_sriov_get_totalvfs(struct pci_dev *dev)
 {
        if (!dev->is_physfn)
-               return -EINVAL;
+               return 0;
 
        if (dev->sriov->driver_max_VFs)
                return dev->sriov->driver_max_VFs;
--

1.8.3.1