[PATCHv6 4/5] pci/msix: Skip disabling disconnected devices

[Keith Busch <keith.busch@intel.com>]

This patch checks the device connected state prior to executing device
shutdown operations or writing msi messages so that tear down on
disconnected devices completes quicker.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 drivers/pci/msi.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 50c5003..17807eb3 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -317,7 +317,7 @@ void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 {
 	struct pci_dev *dev = msi_desc_to_pci_dev(entry);
 
-	if (dev->current_state != PCI_D0) {
+	if (dev->current_state != PCI_D0 || pci_dev_is_disconnected(dev)) {
 		/* Don't touch the hardware now */
 	} else if (entry->msi_attrib.is_msix) {
 		void __iomem *base = pci_msix_desc_addr(entry);
@@ -1020,6 +1020,11 @@ void pci_msix_shutdown(struct pci_dev *dev)
 	if (!pci_msi_enable || !dev || !dev->msix_enabled)
 		return;
 
+	if (pci_dev_is_disconnected(dev)) {
+		dev->msix_enabled = 0;
+		return;
+	}
+
 	/* Return the device with MSI-X masked as initial states */
 	for_each_pci_msi_entry(entry, dev) {
 		/* Keep cached states to be restored */
-- 
2.7.2