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path: root/drivers/base/init.c
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2013-12-29ACPI / hotplug / driver core: Handle containers in a special wayRafael J. Wysocki
ACPI container devices require special hotplug handling, at least on some systems, since generally user space needs to carry out system-specific cleanup before it makes sense to offline devices in the container. However, the current ACPI hotplug code for containers first attempts to offline devices in the container and only then it notifies user space of the container offline. Moreover, after commit 202317a573b2 (ACPI / scan: Add acpi_device objects for all device nodes in the namespace), ACPI device objects representing containers are present as long as the ACPI namespace nodes corresponding to them are present, which may be forever, even if the container devices are physically detached from the system (the return values of the corresponding _STA methods change in those cases, but generally the namespace nodes themselves are still there). Thus it is useful to introduce entities representing containers that will go away during container hot-unplug. The goal of this change is to address both the above issues. The idea is to create a "companion" container system device for each of the ACPI container device objects during the initial namespace scan or on a hotplug event making the container present. That system device will be unregistered on container removal. A new bus type for container devices is added for this purpose, because device offline and online operations need to be defined for them. The online operation is a trivial function that is always successful and the offline uses a callback pointed to by the container device's offline member. For ACPI containers that callback simply walks the list of ACPI device objects right below the container object (its children) and checks if all of their physical companion devices are offline. If that's not the case, it returns -EBUSY and the container system devivce cannot be put offline. Consequently, to put the container system device offline, it is necessary to put all of the physical devices depending on its ACPI companion object offline beforehand. Container system devices created for ACPI container objects are initially online. They are created by the container ACPI scan handler whose hotplug.demand_offline flag is set. That causes acpi_scan_hot_remove() to check if the companion container system device is offline before attempting to remove an ACPI container or any devices below it. If the check fails, a KOBJ_CHANGE uevent is emitted for the container system device in question and user space is expected to offline all devices below the container and the container itself in response to it. Then, user space can finalize the removal of the container with the help of its ACPI device object's eject attribute in sysfs. Tested-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2011-12-14driver-core: implement 'sysdev' functionality for regular devices and busesKay Sievers
All sysdev classes and sysdev devices will converted to regular devices and buses to properly hook userspace into the event processing. There is no interesting difference between a 'sysdev' and 'device' which would justify to roll an entire own subsystem with different userspace export semantics. Userspace relies on events and generic sysfs subsystem infrastructure from sysdev devices, which are currently not properly available. Every converted sysdev class will create a regular device with the class name in /sys/devices/system and all registered devices will becom a children of theses devices. For compatibility reasons, the sysdev class-wide attributes are created at this parent device. (Do not copy that logic for anything new, subsystem- wide properties belong to the subsystem, not to some fake parent device created in /sys/devices.) Every sysdev driver is implemented as a simple subsystem interface now, and no longer called a driver. After all sysdev classes are ported to regular driver core entities, the sysdev implementation will be entirely removed from the kernel. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-15Driver Core: devtmpfs - kernel-maintained tmpfs-based /devKay Sievers
Devtmpfs lets the kernel create a tmpfs instance called devtmpfs very early at kernel initialization, before any driver-core device is registered. Every device with a major/minor will provide a device node in devtmpfs. Devtmpfs can be changed and altered by userspace at any time, and in any way needed - just like today's udev-mounted tmpfs. Unmodified udev versions will run just fine on top of it, and will recognize an already existing kernel-created device node and use it. The default node permissions are root:root 0600. Proper permissions and user/group ownership, meaningful symlinks, all other policy still needs to be applied by userspace. If a node is created by devtmps, devtmpfs will remove the device node when the device goes away. If the device node was created by userspace, or the devtmpfs created node was replaced by userspace, it will no longer be removed by devtmpfs. If it is requested to auto-mount it, it makes init=/bin/sh work without any further userspace support. /dev will be fully populated and dynamic, and always reflect the current device state of the kernel. With the commonly used dynamic device numbers, it solves the problem where static devices nodes may point to the wrong devices. It is intended to make the initial bootup logic simpler and more robust, by de-coupling the creation of the inital environment, to reliably run userspace processes, from a complex userspace bootstrap logic to provide a working /dev. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jan Blunck <jblunck@suse.de> Tested-By: Harald Hoyer <harald@redhat.com> Tested-By: Scott James Remnant <scott@ubuntu.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24Driver core: coding style fixesGreg Kroah-Hartman
Fix up a number of coding style issues in the drivers/base/ directory that have annoyed me over the years. checkpatch.pl is now very happy. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24Driver core: use LIST_HEAD instead of call to INIT_LIST_HEAD in __initDenis Cheng
LIST_HEAD has been widely used, so switch to this simpler method. Signed-off-by: Denis Cheng <crquan@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-21[PATCH] Driver Core: Add /sys/hypervisor when neededMichael Holzheu
To have a home for all hypervisors, this patch creates /sys/hypervisor. A new config option SYS_HYPERVISOR is introduced, which should to be set by architecture dependent hypervisors (e.g. s390 or Xen). Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Michael Holzheu <holzheu@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-10-29[PATCH] memory hotplug: sysfs and add/remove functionsDave Hansen
This adds generic memory add/remove and supporting functions for memory hotplug into a new file as well as a memory hotplug kernel config option. Individual architecture patches will follow. For now, disable memory hotplug when swsusp is enabled. There's a lot of churn there right now. We'll fix it up properly once it calms down. Signed-off-by: Matt Tolentino <matthew.e.tolentino@intel.com> Signed-off-by: Dave Hansen <haveblue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-28[PATCH] drivers/base - fix sparse warningsBen Dooks
There are a number of sparse warnings from the latest sparse snapshot being generated from the drivers/base build. The main culprits are due to the initialisation functions not being declared in a header file. Also, the firmware.c file should include <linux/device.h> to get the prototype of firmware_register() and firmware_unregister(). This patch moves the init function declerations from the init.c file to the base.h, and ensures it is included in all the relevant c sources. It also adds <linux/device.h> to the included headers for firmware.c. The patch does not solve all the sparse errors generated, but reduces the count significantly. drivers/base/core.c:161:1: warning: symbol 'devices_subsys' was not declared. Should it be static? drivers/base/core.c:417:12: warning: symbol 'devices_init' was not declared. Should it be static? drivers/base/sys.c:253:6: warning: symbol 'sysdev_shutdown' was not declared. Should it be static? drivers/base/sys.c:326:5: warning: symbol 'sysdev_suspend' was not declared. Should it be static? drivers/base/sys.c:428:5: warning: symbol 'sysdev_resume' was not declared. Should it be static? drivers/base/sys.c:450:12: warning: symbol 'system_bus_init' was not declared. Should it be static? drivers/base/bus.c:133:1: warning: symbol 'bus_subsys' was not declared. Should it be static? drivers/base/bus.c:667:12: warning: symbol 'buses_init' was not declared. Should it be static? drivers/base/class.c:759:12: warning: symbol 'classes_init' was not declared. Should it be static? drivers/base/platform.c:313:12: warning: symbol 'platform_bus_init' was not declared. Should it be static? drivers/base/cpu.c:110:12: warning: symbol 'cpu_dev_init' was not declared. Should it be static? drivers/base/firmware.c:17:5: warning: symbol 'firmware_register' was not declared. Should it be static? drivers/base/firmware.c:23:6: warning: symbol 'firmware_unregister' was not declared. Should it be static? drivers/base/firmware.c:28:12: warning: symbol 'firmware_init' was not declared. Should it be static? drivers/base/init.c:28:13: warning: symbol 'driver_init' was not declared. Should it be static? drivers/base/dmapool.c:174:10: warning: implicit cast from nocast type drivers/base/attribute_container.c:439:1: warning: symbol 'attribute_container_init' was not declared. Should it be static? drivers/base/power/runtime.c:76:6: warning: symbol 'dpm_set_power_state' was not declared. Should it be static? Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!