Received-SPF: pass (google.com: domain of linux-kernel+bounces-12801-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:40f1:3f00::1 as permitted sender) client-ip=2604:1380:40f1:3f00::1;
From: Ethan Zhao <haifeng.zhao@linux.intel.com>
To: kevin.tian@intel.com,
	bhelgaas@google.com,
	baolu.lu@linux.intel.com,
	dwmw2@infradead.org,
	will@kernel.org,
	robin.murphy@arm.com,
	lukas@wunner.de
Cc: linux-pci@vger.kernel.org,
	iommu@lists.linux.dev,
	linux-kernel@vger.kernel.org
Subject: [RFC PATCH v10 3/5] PCI: make pci_dev_is_disconnected() helper public for other drivers
Date: Thu, 28 Dec 2023 12:05:02 -0500
Message-Id: <20231228170504.720794-1-haifeng.zhao@linux.intel.com>
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit

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.

Tested-by: Haorong Ye <yehaorong@bytedance.com>
Signed-off-by: Ethan Zhao <haifeng.zhao@linux.intel.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 5ecbcf041179..75fa2084492f 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -366,11 +366,6 @@ 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 dea043bc1e38..4779eec8b267 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -2506,6 +2506,11 @@ 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,
-- 
2.31.1