[PATCH 6.6 293/638] PCI: Make pci_dev_is_disconnected() helper public for other drivers

From: Sasha Levin
Date: Mon Mar 25 2024 - 07:38:20 EST


From: Ethan Zhao <haifeng.zhao@xxxxxxxxxxxxxxx>

[ 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@xxxxxxxxxx>
Reviewed-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Tested-by: Haorong Ye <yehaorong@xxxxxxxxxxxxx>
Signed-off-by: Ethan Zhao <haifeng.zhao@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240301080727.3529832-2-haifeng.zhao@xxxxxxxxxxxxxxx
Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
Stable-dep-of: 4fc82cd907ac ("iommu/vt-d: Don't issue ATS Invalidation request when device is disconnected")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 99abc4cec0df1..1b4f941829724 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -363,11 +363,6 @@ 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 3af5f29985511..b548d5646a86d 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -2477,6 +2477,11 @@ 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