PCI: Make pci_dev_is_disconnected() helper public for other drivers

[ Upstream commit 39714fd73c6b60a8d27bcc5b431afb0828bf4434 ]

Make pci_dev_is_disconnected() public so that it can be called from
Intel VT-d driver to quickly fix/workaround the surprise removal
unplug hang issue for those ATS capable devices on PCIe switch downstream
hotplug capable ports.

Beside pci_device_is_present() function, this one has no config space
space access, so is light enough to optimize the normal pure surprise
removal and safe removal flow.

Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Tested-by: Haorong Ye <yehaorong@bytedance.com>
Signed-off-by: Ethan Zhao <haifeng.zhao@linux.intel.com>
Link: https://lore.kernel.org/r/20240301080727.3529832-2-haifeng.zhao@linux.intel.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Stable-dep-of: 4fc82cd907ac ("iommu/vt-d: Don't issue ATS Invalidation request when device is disconnected")
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 72436000ff2525cb11c00e4e74e1f7ed5705d92a..32fa07bfc448e541ed3af636c5530eb9391c7fa5 100644 (file)
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -399,11 +399,6 @@ static inline int pci_dev_set_disconnected(struct pci_dev *dev, void *unused)
        return 0;
 }
 
-static inline bool pci_dev_is_disconnected(const struct pci_dev *dev)
-{
-       return dev->error_state == pci_channel_io_perm_failure;
-}
-
 /* pci_dev priv_flags */
 #define PCI_DEV_ADDED 0
 #define PCI_DPC_RECOVERED 1

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 550e1cdb473fa903abc71f16045510f0b2da39d3..bf46453475e310fef7edc9e14eb617c12cf88b57 100644 (file)
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -2191,6 +2191,11 @@ static inline struct pci_dev *pcie_find_root_port(struct pci_dev *dev)
        return NULL;
 }
 
+static inline bool pci_dev_is_disconnected(const struct pci_dev *dev)
+{
+       return dev->error_state == pci_channel_io_perm_failure;
+}
+
 void pci_request_acs(void);
 bool pci_acs_enabled(struct pci_dev *pdev, u16 acs_flags);
 bool pci_acs_path_enabled(struct pci_dev *start,