From 89ee9f7680031d7df91a1a27abac69e034c2e892 Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Wed, 29 Mar 2017 22:48:59 -0500 Subject: [PATCH] PCI: Add device disconnected state Add a new state to pci_dev to be set when it is unexpectedly disconnected. The PCI driver tear down functions can observe this new device state so they may skip operations that will fail. The pciehp and pcie-dpc drivers are aware when the link is down, so these set the flag when their handlers detect the device is disconnected. Tested-by: Krishna Dhulipala Signed-off-by: Keith Busch Signed-off-by: Bjorn Helgaas Reviewed-by: Christoph Hellwig Reviewed-by: Wei Zhang --- drivers/pci/hotplug/pciehp_pci.c | 6 ++++++ drivers/pci/pci.h | 14 ++++++++++++++ drivers/pci/pcie/pcie-dpc.c | 5 +++++ include/linux/pci.h | 2 ++ 4 files changed, 27 insertions(+) diff --git a/drivers/pci/hotplug/pciehp_pci.c b/drivers/pci/hotplug/pciehp_pci.c index 9e69403..19f30a9 100644 --- a/drivers/pci/hotplug/pciehp_pci.c +++ b/drivers/pci/hotplug/pciehp_pci.c @@ -109,6 +109,12 @@ int pciehp_unconfigure_device(struct slot *p_slot) break; } } + if (!presence) { + pci_dev_set_disconnected(dev, NULL); + if (pci_has_subordinate(dev)) + pci_walk_bus(dev->subordinate, + pci_dev_set_disconnected, NULL); + } pci_stop_and_remove_bus_device(dev); /* * Ensure that no new Requests will be generated from diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 8dd38e6..245719c 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -274,6 +274,20 @@ struct pci_sriov { resource_size_t barsz[PCI_SRIOV_NUM_BARS]; /* VF BAR size */ }; +/* pci_dev priv_flags */ +#define PCI_DEV_DISCONNECTED 0 + +static inline int pci_dev_set_disconnected(struct pci_dev *dev, void *unused) +{ + set_bit(PCI_DEV_DISCONNECTED, &dev->priv_flags); + return 0; +} + +static inline bool pci_dev_is_disconnected(const struct pci_dev *dev) +{ + return test_bit(PCI_DEV_DISCONNECTED, &dev->priv_flags); +} + #ifdef CONFIG_PCI_ATS void pci_restore_ats_state(struct pci_dev *dev); #else diff --git a/drivers/pci/pcie/pcie-dpc.c b/drivers/pci/pcie/pcie-dpc.c index d4d70ef..77d2ca9 100644 --- a/drivers/pci/pcie/pcie-dpc.c +++ b/drivers/pci/pcie/pcie-dpc.c @@ -14,6 +14,7 @@ #include #include #include +#include "../pci.h" struct dpc_dev { struct pcie_device *dev; @@ -66,6 +67,10 @@ static void interrupt_event_handler(struct work_struct *work) list_for_each_entry_safe_reverse(dev, temp, &parent->devices, bus_list) { pci_dev_get(dev); + pci_dev_set_disconnected(dev, NULL); + if (pci_has_subordinate(dev)) + pci_walk_bus(dev->subordinate, + pci_dev_set_disconnected, NULL); pci_stop_and_remove_bus_device(dev); pci_dev_put(dev); } diff --git a/include/linux/pci.h b/include/linux/pci.h index d705f30..2887933 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -396,6 +396,8 @@ struct pci_dev { phys_addr_t rom; /* Physical address of ROM if it's not from the BAR */ size_t romlen; /* Length of ROM if it's not from the BAR */ char *driver_override; /* Driver name to force a match */ + + unsigned long priv_flags; /* Private flags for the pci driver */ }; static inline struct pci_dev *pci_physfn(struct pci_dev *dev) -- 2.7.4