[SRU][F][PATCH 1/2] PCI: Make pci_dev_is_disconnected() helper public for other drivers

[Koichiro Den]

From: Ethan Zhao <haifeng.zhao at linux.intel.com>

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 at google.com>
Reviewed-by: Dan Carpenter <dan.carpenter at linaro.org>
Tested-by: Haorong Ye <yehaorong at bytedance.com>
Signed-off-by: Ethan Zhao <haifeng.zhao at linux.intel.com>
Link: https://lore.kernel.org/r/20240301080727.3529832-2-haifeng.zhao@linux.intel.com
Signed-off-by: Lu Baolu <baolu.lu at linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel at suse.de>
(cherry picked from commit 39714fd73c6b60a8d27bcc5b431afb0828bf4434)
CVE-2024-26891
Signed-off-by: Koichiro Den <koichiro.den at canonical.com>
---
 drivers/pci/pci.h   | 5 -----
 include/linux/pci.h | 5 +++++
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index d1fe10231fa3..57cf87b93fa1 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -391,11 +391,6 @@ 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
 
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 04c1ad7711d7..1a4df35d2d15 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -2180,6 +2180,11 @@ 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,
-- 
2.43.0