PCI: Add pcim_set_mwi(), a device-managed pci_set_mwi()

Add pcim_set_mwi(), a device-managed version of pci_set_mwi().
First user is the Realtek r8169 driver.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/pci/pci.c

@@ -1458,6 +1458,7 @@ struct pci_devres {
 	unsigned int pinned:1;
 	unsigned int orig_intx:1;
 	unsigned int restore_intx:1;
+	unsigned int mwi:1;
 	u32 region_mask;
 };
 
@@ -1476,6 +1477,9 @@ static void pcim_release(struct device *gendev, void *res)
 		if (this->region_mask & (1 << i))
 			pci_release_region(dev, i);
 
+	if (this->mwi)
+		pci_clear_mwi(dev);
+
 	if (this->restore_intx)
 		pci_intx(dev, this->orig_intx);
 
@@ -3760,6 +3764,27 @@ int pci_set_mwi(struct pci_dev *dev)
 }
 EXPORT_SYMBOL(pci_set_mwi);
 
+/**
+ * pcim_set_mwi - a device-managed pci_set_mwi()
+ * @dev: the PCI device for which MWI is enabled
+ *
+ * Managed pci_set_mwi().
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int pcim_set_mwi(struct pci_dev *dev)
+{
+	struct pci_devres *dr;
+
+	dr = find_pci_dr(dev);
+	if (!dr)
+		return -ENOMEM;
+
+	dr->mwi = 1;
+	return pci_set_mwi(dev);
+}
+EXPORT_SYMBOL(pcim_set_mwi);
+
 /**
  * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
  * @dev: the PCI device for which MWI is enabled

include/linux/pci.h

@@ -1072,6 +1072,7 @@ int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state);
 int pci_set_cacheline_size(struct pci_dev *dev);
 #define HAVE_PCI_SET_MWI
 int __must_check pci_set_mwi(struct pci_dev *dev);
+int __must_check pcim_set_mwi(struct pci_dev *dev);
 int pci_try_set_mwi(struct pci_dev *dev);
 void pci_clear_mwi(struct pci_dev *dev);
 void pci_intx(struct pci_dev *dev, int enable);