738a7edbfc
This function is always called with an existing pci_dev struct, which holds a reference on the pci_bus struct it resides on, which in turn holds a reference on pci_bus->bridge, which is the pci_dev's parent. Hence there's no need to acquire an additional ref on the parent. More specifically, the pci_dev exists until pci_destroy_dev() drops the final reference on it, so all calls to pci_bridge_d3_update() must be finished before that. It is arguably the caller's responsibility to ensure that it doesn't call pci_bridge_d3_update() with a pci_dev that might suddenly disappear, but in any case the existing callers are all safe: - The call in pci_destroy_dev() happens before the call to put_device(). - The call in pci_bus_add_device() is synchronized with pci_destroy_dev() using pci_lock_rescan_remove(). - The calls to pci_d3cold_disable() from the xhci and nouveau drivers are safe because a ref on the pci_dev is held as long as it's bound to a driver. - The calls to pci_d3cold_enable() / pci_d3cold_disable() when modifying the sysfs "d3cold_allowed" entry are also safe because kernfs_drain() waits for existing sysfs users to finish before removing the entry, and pci_destroy_dev() is called way after that. No functional change intended. Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> |
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.. | ||
host | ||
hotplug | ||
pcie | ||
access.c | ||
ats.c | ||
bus.c | ||
ecam.c | ||
host-bridge.c | ||
hotplug-pci.c | ||
htirq.c | ||
iov.c | ||
irq.c | ||
Kconfig | ||
Makefile | ||
msi.c | ||
of.c | ||
pci-acpi.c | ||
pci-driver.c | ||
pci-label.c | ||
pci-mid.c | ||
pci-stub.c | ||
pci-sysfs.c | ||
pci.c | ||
pci.h | ||
probe.c | ||
proc.c | ||
quirks.c | ||
remove.c | ||
rom.c | ||
search.c | ||
setup-bus.c | ||
setup-irq.c | ||
setup-res.c | ||
slot.c | ||
syscall.c | ||
vc.c | ||
vpd.c | ||
xen-pcifront.c |