kernel/drivers/pci/hotplug/acpiphp.h, branch linux-4.3.y

ACPI / hotplug / PCI: Add hotplug contexts to PCI host bridges

2014-06-11T19:08:49Z

After relatively recent changes in the ACPI-based PCI hotplug (ACPIPHP) code, the acpiphp_check_host_bridge() executed for PCI host bridges via acpi_pci_root_scan_dependent() doesn't do anything useful, because those bridges do not have hotplug contexts. That happens by mistake, so fix it by making acpiphp_enumerate_slots() add hotplug contexts to PCI host bridges too and modify acpiphp_remove_slots() to drop those contexts for host bridges as appropriate. Link: https://bugzilla.kernel.org/show_bug.cgi?id=76901 Fixes: 2d8b1d566a5f (ACPI / hotplug / PCI: Get rid of check_sub_bridges()) Reported-and-tested-by: Gavin Guo Acked-by: Bjorn Helgaas Reviewed-by: Mika Westerberg Cc: 3.15+ # 3.15+ Signed-off-by: Rafael J. Wysocki

ACPI / hotplug / PCI: Hotplug notifications from acpi_bus_notify()

2014-02-06T16:31:52Z

Since acpi_bus_notify() is executed on all notifications for all devices anyway, make it execute acpi_device_hotplug() for all hotplug events instead of installing notify handlers pointing to the same function for all hotplug devices. This change reduces both the size and complexity of ACPI-based device hotplug code. Moreover, since acpi_device_hotplug() only does significant things for devices that have either an ACPI scan handler, or a hotplug context with .eject() defined, and those devices had notify handlers pointing to acpi_hotplug_notify_cb() installed before anyway, this modification shouldn't change functionality. Signed-off-by: Rafael J. Wysocki

ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug

2014-02-06T16:31:37Z

The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki

ACPI / hotplug / PCI: Drop crit_sect locking

2014-02-05T16:40:57Z

After recent PCI core changes related to the rescan/remove locking, the code sections under crit_sect mutexes from ACPIPHP slot objects are always executed under the general PCI rescan/remove lock. For this reason, the crit_sect mutexes are simply redundant, so drop them. Signed-off-by: Rafael J. Wysocki Tested-by: Mika Westerberg

ACPI / hotplug / PCI: Store acpi_device pointer in acpiphp_context

2014-02-05T16:40:39Z

After recent modifications of the ACPI core making it create a struct acpi_device object for every namespace node representing a device regardless of the current status of that device the ACPIPHP code can store a struct acpi_device pointer instead of an ACPI handle in struct acpiphp_context. This immediately makes it possible to avoid making potentially costly calls to acpi_bus_get_device() in two places and allows some more simplifications to be made going forward. The reason why that is correct is because ACPIPHP only installs hotify handlers for namespace nodes that exist when acpiphp_enumerate_slots() is called for their parent bridge. That only happens if the parent bridge has an ACPI companion associated with it, which means that the ACPI namespace scope in question has been scanned already at that point. That, in turn, means that struct acpi_device objects have been created for all namespace nodes in that scope and pointers to those objects can be stored directly instead of their ACPI handles. Signed-off-by: Rafael J. Wysocki Tested-by: Mika Westerberg

ACPI / hotplug / PCI: Use global PCI rescan-remove locking

2014-01-14T19:14:25Z

Multiple race conditions are possible between the ACPI-based PCI hotplug (ACPIPHP) and the generic PCI bus rescan and device removal that can be triggered via sysfs. To avoid those race conditions make the ACPIPHP code use global PCI rescan-remove locking. Signed-off-by: Rafael J. Wysocki Signed-off-by: Bjorn Helgaas

Merge branch 'acpi-hotplug'

2013-11-19T20:18:13Z

* acpi-hotplug: PCI / hotplug / ACPI: Drop unused acpiphp_debug declaration

PCI / hotplug / ACPI: Drop unused acpiphp_debug declaration

2013-11-19T20:17:59Z

Commit bd950799d951 (PCI: acpiphp: Convert to dynamic debug) removed users of acpiphp_debug variable and the variable itself but the declaration was left in the header file. Drop this unused declaration. Signed-off-by: Mika Westerberg Acked-by: Bjorn Helgaas Signed-off-by: Rafael J. Wysocki

PCI: acpiphp: Convert to dynamic debug

2013-09-25T23:00:51Z

This patch is to use pr_debug/info/warn/err to replace acpiphp debug functions and remove module's debug param. User interface change: before this patch, boot with the "acpiphp.debug" kernel parameter to turn on debug. After this patch, set CONFIG_DYNAMIC_DEBUG=y and boot with "acpiphp.dyndebug=+p" instead. See Documentation/dynamic-debug-howto.txt. [bhelgaas: changelog] Signed-off-by: Lan Tianyu Signed-off-by: Bjorn Helgaas

ACPI / hotplug / PCI: Get rid of unused constants in acpiphp.h

2013-07-23T02:00:27Z

Drop some unused symbols from acpiphp.h and redefine SLOT_ENABLED (which is the only slot flag now) as 1. [rjw: Redefinition of SLOT_ENABLED, changelog] Signed-off-by: Mika Westerberg Signed-off-by: Kirill A. Shutemov Signed-off-by: Rafael J. Wysocki