2005-04-16 16:20:36 -06:00
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/*
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* drivers/base/core.c - core driver model code (device registration, etc)
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*
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* Copyright (c) 2002-3 Patrick Mochel
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* Copyright (c) 2002-3 Open Source Development Labs
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2006-06-28 17:19:58 -06:00
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* Copyright (c) 2006 Greg Kroah-Hartman <gregkh@suse.de>
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* Copyright (c) 2006 Novell, Inc.
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2005-04-16 16:20:36 -06:00
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*
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* This file is released under the GPLv2
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*
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*/
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#include <linux/device.h>
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#include <linux/err.h>
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/slab.h>
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#include <linux/string.h>
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2006-06-14 13:14:34 -06:00
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#include <linux/kdev_t.h>
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Driver core: add notification of bus events
I finally did as you suggested and added the notifier to the struct
bus_type itself. There are still problems to be expected is something
attaches to a bus type where the code can hook in different struct
device sub-classes (which is imho a big bogosity but I won't even try to
argue that case now) but it will solve nicely a number of issues I've
had so far.
That also means that clients interested in registering for such
notifications have to do it before devices are added and after bus types
are registered. Fortunately, most bus types that matter for the various
usage scenarios I have in mind are registerd at postcore_initcall time,
which means I have a really nice spot at arch_initcall time to add my
notifiers.
There are 4 notifications provided. Device being added (before hooked to
the bus) and removed (failure of previous case or after being unhooked
from the bus), along with driver being bound to a device and about to be
unbound.
The usage I have for these are:
- The 2 first ones are used to maintain a struct device_ext that is
hooked to struct device.firmware_data. This structure contains for now a
pointer to the Open Firmware node related to the device (if any), the
NUMA node ID (for quick access to it) and the DMA operations pointers &
iommu table instance for DMA to/from this device. For bus types I own
(like IBM VIO or EBUS), I just maintain that structure directly from the
bus code when creating the devices. But for bus types managed by generic
code like PCI or platform (actually, of_platform which is a variation of
platform linked to Open Firmware device-tree), I need this notifier.
- The other two ones have a completely different usage scenario. I have
cases where multiple devices and their drivers depend on each other. For
example, the IBM EMAC network driver needs to attach to a MAL DMA engine
which is a separate device, and a PHY interface which is also a separate
device. They are all of_platform_device's (well, about to be with my
upcoming patches) but there is no say in what precise order the core
will "probe" them and instanciate the various modules. The solution I
found for that is to have the drivers for emac to use multithread_probe,
and wait for a driver to be bound to the target MAL and PHY control
devices (the device-tree contains reference to the MAL and PHY interface
nodes, which I can then match to of_platform_devices). Right now, I've
been polling, but with that notifier, I can more cleanly wait (with a
timeout of course).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-10-24 21:44:59 -06:00
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#include <linux/notifier.h>
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2012-02-01 11:22:22 -07:00
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#include <linux/of.h>
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#include <linux/of_device.h>
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2007-11-21 09:29:15 -07:00
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#include <linux/genhd.h>
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2008-03-04 16:09:07 -07:00
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#include <linux/kallsyms.h>
|
2008-05-28 10:28:39 -06:00
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#include <linux/mutex.h>
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PM / driver core: disable device's runtime PM during shutdown
There may be an issue when the user issue "reboot/shutdown" command, then
the device has shut down its hardware, after that, this runtime-pm featured
device's driver will probably be scheduled to do its suspend routine,
and at its suspend routine, it may access hardware, but the device has
already shutdown physically, then the system hang may be occurred.
I ran out this issue using an auto-suspend supported USB devices, like
3G modem, keyboard. The usb runtime suspend routine may be scheduled
after the usb controller has been shut down, and the usb runtime suspend
routine will try to suspend its roothub(controller), it will access
register, then the system hang occurs as the controller is shutdown.
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Acked-by: Ming Lei <tom.leiming@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Cc: stable@kernel.org
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-11-15 13:52:29 -07:00
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#include <linux/pm_runtime.h>
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2012-05-02 18:29:59 -06:00
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#include <linux/netdevice.h>
|
2013-08-27 11:24:15 -06:00
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#include <linux/sysfs.h>
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2005-04-16 16:20:36 -06:00
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#include "base.h"
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#include "power/power.h"
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|
2010-09-08 08:54:17 -06:00
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#ifdef CONFIG_SYSFS_DEPRECATED
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#ifdef CONFIG_SYSFS_DEPRECATED_V2
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long sysfs_deprecated = 1;
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#else
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long sysfs_deprecated = 0;
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#endif
|
2013-08-17 06:42:24 -06:00
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static int __init sysfs_deprecated_setup(char *arg)
|
2010-09-08 08:54:17 -06:00
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{
|
2013-07-25 22:10:22 -06:00
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return kstrtol(arg, 10, &sysfs_deprecated);
|
2010-09-08 08:54:17 -06:00
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}
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early_param("sysfs.deprecated", sysfs_deprecated_setup);
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#endif
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2008-01-24 23:50:12 -07:00
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int (*platform_notify)(struct device *dev) = NULL;
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int (*platform_notify_remove)(struct device *dev) = NULL;
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2008-04-21 11:51:07 -06:00
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static struct kobject *dev_kobj;
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struct kobject *sysfs_dev_char_kobj;
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struct kobject *sysfs_dev_block_kobj;
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2005-04-16 16:20:36 -06:00
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driver core / ACPI: Avoid device hot remove locking issues
device_hotplug_lock is held around the acpi_bus_trim() call in
acpi_scan_hot_remove() which generally removes devices (it removes
ACPI device objects at least, but it may also remove "physical"
device objects through .detach() callbacks of ACPI scan handlers).
Thus, potentially, device sysfs attributes are removed under that
lock and to remove those attributes it is necessary to hold the
s_active references of their directory entries for writing.
On the other hand, the execution of a .show() or .store() callback
from a sysfs attribute is carried out with that attribute's s_active
reference held for reading. Consequently, if any device sysfs
attribute that may be removed from within acpi_scan_hot_remove()
through acpi_bus_trim() has a .store() or .show() callback which
acquires device_hotplug_lock, the execution of that callback may
deadlock with the removal of the attribute. [Unfortunately, the
"online" device attribute of CPUs and memory blocks is one of them.]
To avoid such deadlocks, make all of the sysfs attribute callbacks
that need to lock device hotplug, for example store_online(), use
a special function, lock_device_hotplug_sysfs(), to lock device
hotplug and return the result of that function immediately if it is
not zero. This will cause the s_active reference of the directory
entry in question to be released and the syscall to be restarted
if device_hotplug_lock cannot be acquired.
[show_online() actually doesn't need to lock device hotplug, but
it is useful to serialize it with respect to device_offline() and
device_online() for the same device (in case user space attempts to
run them concurrently) which can be done with the help of
device_lock().]
Reported-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Reported-and-tested-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
2013-08-28 13:41:01 -06:00
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static DEFINE_MUTEX(device_hotplug_lock);
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void lock_device_hotplug(void)
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{
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mutex_lock(&device_hotplug_lock);
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}
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void unlock_device_hotplug(void)
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{
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mutex_unlock(&device_hotplug_lock);
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}
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int lock_device_hotplug_sysfs(void)
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{
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if (mutex_trylock(&device_hotplug_lock))
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return 0;
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/* Avoid busy looping (5 ms of sleep should do). */
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msleep(5);
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return restart_syscall();
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}
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|
2008-01-27 13:12:43 -07:00
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#ifdef CONFIG_BLOCK
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static inline int device_is_not_partition(struct device *dev)
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{
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return !(dev->type == &part_type);
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}
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#else
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static inline int device_is_not_partition(struct device *dev)
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{
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return 1;
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}
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#endif
|
2005-04-16 16:20:36 -06:00
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2006-06-16 15:10:48 -06:00
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/**
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* dev_driver_string - Return a device's driver name, if at all possible
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* @dev: struct device to get the name of
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*
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* Will return the device's driver's name if it is bound to a device. If
|
2012-04-20 07:08:45 -06:00
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* the device is not bound to a driver, it will return the name of the bus
|
2006-06-16 15:10:48 -06:00
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* it is attached to. If it is not attached to a bus either, an empty
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* string will be returned.
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*/
|
2008-07-30 13:29:21 -06:00
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const char *dev_driver_string(const struct device *dev)
|
2006-06-16 15:10:48 -06:00
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{
|
2009-12-04 09:06:57 -07:00
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struct device_driver *drv;
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/* dev->driver can change to NULL underneath us because of unbinding,
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* so be careful about accessing it. dev->bus and dev->class should
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* never change once they are set, so they don't need special care.
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*/
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drv = ACCESS_ONCE(dev->driver);
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return drv ? drv->name :
|
2007-03-09 08:33:10 -07:00
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(dev->bus ? dev->bus->name :
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(dev->class ? dev->class->name : ""));
|
2006-06-16 15:10:48 -06:00
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}
|
2006-09-23 23:35:04 -06:00
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EXPORT_SYMBOL(dev_driver_string);
|
2006-06-16 15:10:48 -06:00
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|
2005-04-16 16:20:36 -06:00
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#define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr)
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|
2008-01-24 23:50:12 -07:00
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static ssize_t dev_attr_show(struct kobject *kobj, struct attribute *attr,
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char *buf)
|
2005-04-16 16:20:36 -06:00
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{
|
2008-01-24 23:50:12 -07:00
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struct device_attribute *dev_attr = to_dev_attr(attr);
|
2012-07-03 10:49:36 -06:00
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struct device *dev = kobj_to_dev(kobj);
|
2005-04-29 00:23:47 -06:00
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ssize_t ret = -EIO;
|
2005-04-16 16:20:36 -06:00
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if (dev_attr->show)
|
2005-05-17 04:39:34 -06:00
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ret = dev_attr->show(dev, dev_attr, buf);
|
2008-03-04 16:09:07 -07:00
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if (ret >= (ssize_t)PAGE_SIZE) {
|
2013-01-17 14:10:23 -07:00
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print_symbol("dev_attr_show: %s returned bad count\n",
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|
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(unsigned long)dev_attr->show);
|
2008-03-04 16:09:07 -07:00
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}
|
2005-04-16 16:20:36 -06:00
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return ret;
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}
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|
2008-01-24 23:50:12 -07:00
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static ssize_t dev_attr_store(struct kobject *kobj, struct attribute *attr,
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const char *buf, size_t count)
|
2005-04-16 16:20:36 -06:00
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{
|
2008-01-24 23:50:12 -07:00
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struct device_attribute *dev_attr = to_dev_attr(attr);
|
2012-07-03 10:49:36 -06:00
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struct device *dev = kobj_to_dev(kobj);
|
2005-04-29 00:23:47 -06:00
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ssize_t ret = -EIO;
|
2005-04-16 16:20:36 -06:00
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if (dev_attr->store)
|
2005-05-17 04:39:34 -06:00
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ret = dev_attr->store(dev, dev_attr, buf, count);
|
2005-04-16 16:20:36 -06:00
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return ret;
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}
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|
2010-01-18 18:58:23 -07:00
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static const struct sysfs_ops dev_sysfs_ops = {
|
2005-04-16 16:20:36 -06:00
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.show = dev_attr_show,
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.store = dev_attr_store,
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};
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|
2011-12-14 15:29:38 -07:00
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|
#define to_ext_attr(x) container_of(x, struct dev_ext_attribute, attr)
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ssize_t device_store_ulong(struct device *dev,
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struct device_attribute *attr,
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const char *buf, size_t size)
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{
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struct dev_ext_attribute *ea = to_ext_attr(attr);
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char *end;
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unsigned long new = simple_strtoul(buf, &end, 0);
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if (end == buf)
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return -EINVAL;
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*(unsigned long *)(ea->var) = new;
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|
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/* Always return full write size even if we didn't consume all */
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return size;
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}
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EXPORT_SYMBOL_GPL(device_store_ulong);
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ssize_t device_show_ulong(struct device *dev,
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struct device_attribute *attr,
|
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char *buf)
|
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|
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{
|
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|
|
struct dev_ext_attribute *ea = to_ext_attr(attr);
|
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|
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return snprintf(buf, PAGE_SIZE, "%lx\n", *(unsigned long *)(ea->var));
|
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|
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}
|
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EXPORT_SYMBOL_GPL(device_show_ulong);
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|
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ssize_t device_store_int(struct device *dev,
|
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struct device_attribute *attr,
|
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|
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const char *buf, size_t size)
|
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|
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{
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|
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struct dev_ext_attribute *ea = to_ext_attr(attr);
|
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char *end;
|
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|
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long new = simple_strtol(buf, &end, 0);
|
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|
if (end == buf || new > INT_MAX || new < INT_MIN)
|
|
|
|
return -EINVAL;
|
|
|
|
*(int *)(ea->var) = new;
|
|
|
|
/* Always return full write size even if we didn't consume all */
|
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|
|
return size;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(device_store_int);
|
|
|
|
|
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|
|
ssize_t device_show_int(struct device *dev,
|
|
|
|
struct device_attribute *attr,
|
|
|
|
char *buf)
|
|
|
|
{
|
|
|
|
struct dev_ext_attribute *ea = to_ext_attr(attr);
|
|
|
|
|
|
|
|
return snprintf(buf, PAGE_SIZE, "%d\n", *(int *)(ea->var));
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(device_show_int);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2012-10-09 11:52:05 -06:00
|
|
|
ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
|
|
|
|
const char *buf, size_t size)
|
|
|
|
{
|
|
|
|
struct dev_ext_attribute *ea = to_ext_attr(attr);
|
|
|
|
|
|
|
|
if (strtobool(buf, ea->var) < 0)
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
return size;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(device_store_bool);
|
|
|
|
|
|
|
|
ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
|
|
|
|
char *buf)
|
|
|
|
{
|
|
|
|
struct dev_ext_attribute *ea = to_ext_attr(attr);
|
|
|
|
|
|
|
|
return snprintf(buf, PAGE_SIZE, "%d\n", *(bool *)(ea->var));
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(device_show_bool);
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/**
|
2013-06-01 18:17:34 -06:00
|
|
|
* device_release - free device structure.
|
|
|
|
* @kobj: device's kobject.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2013-06-01 18:17:34 -06:00
|
|
|
* This is called once the reference count for the object
|
|
|
|
* reaches 0. We forward the call to the device's release
|
|
|
|
* method, which should handle actually freeing the structure.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2008-01-24 23:50:12 -07:00
|
|
|
static void device_release(struct kobject *kobj)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2012-07-03 10:49:36 -06:00
|
|
|
struct device *dev = kobj_to_dev(kobj);
|
2008-12-16 13:23:36 -07:00
|
|
|
struct device_private *p = dev->p;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2012-07-24 11:42:29 -06:00
|
|
|
/*
|
|
|
|
* Some platform devices are driven without driver attached
|
|
|
|
* and managed resources may have been acquired. Make sure
|
|
|
|
* all resources are released.
|
|
|
|
*
|
|
|
|
* Drivers still can add resources into device after device
|
|
|
|
* is deleted but alive, so release devres here to avoid
|
|
|
|
* possible memory leak.
|
|
|
|
*/
|
|
|
|
devres_release_all(dev);
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
if (dev->release)
|
|
|
|
dev->release(dev);
|
2006-10-07 13:54:55 -06:00
|
|
|
else if (dev->type && dev->type->release)
|
|
|
|
dev->type->release(dev);
|
2006-06-28 17:19:58 -06:00
|
|
|
else if (dev->class && dev->class->dev_release)
|
|
|
|
dev->class->dev_release(dev);
|
2008-07-25 20:45:39 -06:00
|
|
|
else
|
|
|
|
WARN(1, KERN_ERR "Device '%s' does not have a release() "
|
2008-01-24 23:50:12 -07:00
|
|
|
"function, it is broken and must be fixed.\n",
|
2008-10-29 18:36:48 -06:00
|
|
|
dev_name(dev));
|
2008-12-16 13:23:36 -07:00
|
|
|
kfree(p);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
2010-03-30 12:31:25 -06:00
|
|
|
static const void *device_namespace(struct kobject *kobj)
|
|
|
|
{
|
2012-07-03 10:49:36 -06:00
|
|
|
struct device *dev = kobj_to_dev(kobj);
|
2010-03-30 12:31:25 -06:00
|
|
|
const void *ns = NULL;
|
|
|
|
|
|
|
|
if (dev->class && dev->class->ns_type)
|
|
|
|
ns = dev->class->namespace(dev);
|
|
|
|
|
|
|
|
return ns;
|
|
|
|
}
|
|
|
|
|
2007-10-11 10:47:49 -06:00
|
|
|
static struct kobj_type device_ktype = {
|
2005-04-16 16:20:36 -06:00
|
|
|
.release = device_release,
|
|
|
|
.sysfs_ops = &dev_sysfs_ops,
|
2010-03-30 12:31:25 -06:00
|
|
|
.namespace = device_namespace,
|
2005-04-16 16:20:36 -06:00
|
|
|
};
|
|
|
|
|
|
|
|
|
2005-11-16 01:00:00 -07:00
|
|
|
static int dev_uevent_filter(struct kset *kset, struct kobject *kobj)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
|
|
|
struct kobj_type *ktype = get_ktype(kobj);
|
|
|
|
|
2007-10-11 10:47:49 -06:00
|
|
|
if (ktype == &device_ktype) {
|
2012-07-03 10:49:36 -06:00
|
|
|
struct device *dev = kobj_to_dev(kobj);
|
2005-04-16 16:20:36 -06:00
|
|
|
if (dev->bus)
|
|
|
|
return 1;
|
2006-06-14 13:14:34 -06:00
|
|
|
if (dev->class)
|
|
|
|
return 1;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2005-11-16 01:00:00 -07:00
|
|
|
static const char *dev_uevent_name(struct kset *kset, struct kobject *kobj)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2012-07-03 10:49:36 -06:00
|
|
|
struct device *dev = kobj_to_dev(kobj);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2006-06-14 13:14:34 -06:00
|
|
|
if (dev->bus)
|
|
|
|
return dev->bus->name;
|
|
|
|
if (dev->class)
|
|
|
|
return dev->class->name;
|
|
|
|
return NULL;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
2007-08-14 07:15:12 -06:00
|
|
|
static int dev_uevent(struct kset *kset, struct kobject *kobj,
|
|
|
|
struct kobj_uevent_env *env)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2012-07-03 10:49:36 -06:00
|
|
|
struct device *dev = kobj_to_dev(kobj);
|
2005-04-16 16:20:36 -06:00
|
|
|
int retval = 0;
|
|
|
|
|
2009-04-30 07:23:42 -06:00
|
|
|
/* add device node properties if present */
|
2006-06-14 13:14:34 -06:00
|
|
|
if (MAJOR(dev->devt)) {
|
2009-04-30 07:23:42 -06:00
|
|
|
const char *tmp;
|
|
|
|
const char *name;
|
2011-07-23 18:24:48 -06:00
|
|
|
umode_t mode = 0;
|
2013-04-11 12:43:29 -06:00
|
|
|
kuid_t uid = GLOBAL_ROOT_UID;
|
|
|
|
kgid_t gid = GLOBAL_ROOT_GID;
|
2009-04-30 07:23:42 -06:00
|
|
|
|
2007-08-14 07:15:12 -06:00
|
|
|
add_uevent_var(env, "MAJOR=%u", MAJOR(dev->devt));
|
|
|
|
add_uevent_var(env, "MINOR=%u", MINOR(dev->devt));
|
2013-04-06 10:56:00 -06:00
|
|
|
name = device_get_devnode(dev, &mode, &uid, &gid, &tmp);
|
2009-04-30 07:23:42 -06:00
|
|
|
if (name) {
|
|
|
|
add_uevent_var(env, "DEVNAME=%s", name);
|
2009-09-18 15:01:12 -06:00
|
|
|
if (mode)
|
|
|
|
add_uevent_var(env, "DEVMODE=%#o", mode & 0777);
|
2013-04-11 12:43:29 -06:00
|
|
|
if (!uid_eq(uid, GLOBAL_ROOT_UID))
|
|
|
|
add_uevent_var(env, "DEVUID=%u", from_kuid(&init_user_ns, uid));
|
|
|
|
if (!gid_eq(gid, GLOBAL_ROOT_GID))
|
|
|
|
add_uevent_var(env, "DEVGID=%u", from_kgid(&init_user_ns, gid));
|
2013-04-06 10:56:00 -06:00
|
|
|
kfree(tmp);
|
2009-04-30 07:23:42 -06:00
|
|
|
}
|
2006-06-14 13:14:34 -06:00
|
|
|
}
|
|
|
|
|
2007-03-12 14:08:57 -06:00
|
|
|
if (dev->type && dev->type->name)
|
2007-08-14 07:15:12 -06:00
|
|
|
add_uevent_var(env, "DEVTYPE=%s", dev->type->name);
|
2007-03-12 14:08:57 -06:00
|
|
|
|
2006-10-07 13:54:55 -06:00
|
|
|
if (dev->driver)
|
2007-08-14 07:15:12 -06:00
|
|
|
add_uevent_var(env, "DRIVER=%s", dev->driver->name);
|
2006-10-07 13:54:55 -06:00
|
|
|
|
2012-02-01 11:22:22 -07:00
|
|
|
/* Add common DT information about the device */
|
|
|
|
of_device_uevent(dev, env);
|
|
|
|
|
2007-08-14 07:15:12 -06:00
|
|
|
/* have the bus specific function add its stuff */
|
2005-11-16 01:00:00 -07:00
|
|
|
if (dev->bus && dev->bus->uevent) {
|
2007-08-14 07:15:12 -06:00
|
|
|
retval = dev->bus->uevent(dev, env);
|
2006-10-07 13:54:55 -06:00
|
|
|
if (retval)
|
2007-11-29 00:49:41 -07:00
|
|
|
pr_debug("device: '%s': %s: bus uevent() returned %d\n",
|
2008-10-29 18:36:48 -06:00
|
|
|
dev_name(dev), __func__, retval);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
2007-08-14 07:15:12 -06:00
|
|
|
/* have the class specific function add its stuff */
|
2006-06-28 17:19:58 -06:00
|
|
|
if (dev->class && dev->class->dev_uevent) {
|
2007-08-14 07:15:12 -06:00
|
|
|
retval = dev->class->dev_uevent(dev, env);
|
2006-10-07 13:54:55 -06:00
|
|
|
if (retval)
|
2007-11-29 00:49:41 -07:00
|
|
|
pr_debug("device: '%s': %s: class uevent() "
|
2008-10-29 18:36:48 -06:00
|
|
|
"returned %d\n", dev_name(dev),
|
2008-03-04 17:41:05 -07:00
|
|
|
__func__, retval);
|
2006-10-07 13:54:55 -06:00
|
|
|
}
|
|
|
|
|
2010-08-06 13:11:15 -06:00
|
|
|
/* have the device type specific function add its stuff */
|
2006-10-07 13:54:55 -06:00
|
|
|
if (dev->type && dev->type->uevent) {
|
2007-08-14 07:15:12 -06:00
|
|
|
retval = dev->type->uevent(dev, env);
|
2006-10-07 13:54:55 -06:00
|
|
|
if (retval)
|
2007-11-29 00:49:41 -07:00
|
|
|
pr_debug("device: '%s': %s: dev_type uevent() "
|
2008-10-29 18:36:48 -06:00
|
|
|
"returned %d\n", dev_name(dev),
|
2008-03-04 17:41:05 -07:00
|
|
|
__func__, retval);
|
2006-06-28 17:19:58 -06:00
|
|
|
}
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
return retval;
|
|
|
|
}
|
|
|
|
|
2009-12-31 06:52:51 -07:00
|
|
|
static const struct kset_uevent_ops device_uevent_ops = {
|
2005-11-16 01:00:00 -07:00
|
|
|
.filter = dev_uevent_filter,
|
|
|
|
.name = dev_uevent_name,
|
|
|
|
.uevent = dev_uevent,
|
2005-04-16 16:20:36 -06:00
|
|
|
};
|
|
|
|
|
2013-08-23 18:07:26 -06:00
|
|
|
static ssize_t uevent_show(struct device *dev, struct device_attribute *attr,
|
2007-04-05 17:40:38 -06:00
|
|
|
char *buf)
|
|
|
|
{
|
|
|
|
struct kobject *top_kobj;
|
|
|
|
struct kset *kset;
|
2007-08-14 07:15:12 -06:00
|
|
|
struct kobj_uevent_env *env = NULL;
|
2007-04-05 17:40:38 -06:00
|
|
|
int i;
|
|
|
|
size_t count = 0;
|
|
|
|
int retval;
|
|
|
|
|
|
|
|
/* search the kset, the device belongs to */
|
|
|
|
top_kobj = &dev->kobj;
|
2007-08-12 12:43:55 -06:00
|
|
|
while (!top_kobj->kset && top_kobj->parent)
|
|
|
|
top_kobj = top_kobj->parent;
|
2007-04-05 17:40:38 -06:00
|
|
|
if (!top_kobj->kset)
|
|
|
|
goto out;
|
2007-08-12 12:43:55 -06:00
|
|
|
|
2007-04-05 17:40:38 -06:00
|
|
|
kset = top_kobj->kset;
|
|
|
|
if (!kset->uevent_ops || !kset->uevent_ops->uevent)
|
|
|
|
goto out;
|
|
|
|
|
|
|
|
/* respect filter */
|
|
|
|
if (kset->uevent_ops && kset->uevent_ops->filter)
|
|
|
|
if (!kset->uevent_ops->filter(kset, &dev->kobj))
|
|
|
|
goto out;
|
|
|
|
|
2007-08-14 07:15:12 -06:00
|
|
|
env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL);
|
|
|
|
if (!env)
|
2007-05-02 06:14:11 -06:00
|
|
|
return -ENOMEM;
|
|
|
|
|
2007-04-05 17:40:38 -06:00
|
|
|
/* let the kset specific function add its keys */
|
2007-08-14 07:15:12 -06:00
|
|
|
retval = kset->uevent_ops->uevent(kset, &dev->kobj, env);
|
2007-04-05 17:40:38 -06:00
|
|
|
if (retval)
|
|
|
|
goto out;
|
|
|
|
|
|
|
|
/* copy keys to file */
|
2007-08-14 07:15:12 -06:00
|
|
|
for (i = 0; i < env->envp_idx; i++)
|
|
|
|
count += sprintf(&buf[count], "%s\n", env->envp[i]);
|
2007-04-05 17:40:38 -06:00
|
|
|
out:
|
2007-08-14 07:15:12 -06:00
|
|
|
kfree(env);
|
2007-04-05 17:40:38 -06:00
|
|
|
return count;
|
|
|
|
}
|
|
|
|
|
2013-08-23 18:07:26 -06:00
|
|
|
static ssize_t uevent_store(struct device *dev, struct device_attribute *attr,
|
2005-10-01 06:49:43 -06:00
|
|
|
const char *buf, size_t count)
|
|
|
|
{
|
2007-07-08 14:29:26 -06:00
|
|
|
enum kobject_action action;
|
|
|
|
|
2010-01-14 14:54:37 -07:00
|
|
|
if (kobject_action_type(buf, count, &action) == 0)
|
2007-07-08 14:29:26 -06:00
|
|
|
kobject_uevent(&dev->kobj, action);
|
2010-01-14 14:54:37 -07:00
|
|
|
else
|
|
|
|
dev_err(dev, "uevent: unknown action-string\n");
|
2005-10-01 06:49:43 -06:00
|
|
|
return count;
|
|
|
|
}
|
2013-08-23 18:07:26 -06:00
|
|
|
static DEVICE_ATTR_RW(uevent);
|
2005-10-01 06:49:43 -06:00
|
|
|
|
2013-08-23 18:07:26 -06:00
|
|
|
static ssize_t online_show(struct device *dev, struct device_attribute *attr,
|
Driver core: Add offline/online device operations
In some cases, graceful hot-removal of devices is not possible,
although in principle the devices in question support hotplug.
For example, that may happen for the last CPU in the system or
for memory modules holding kernel memory.
In those cases it is nice to be able to check if the given device
can be gracefully hot-removed before triggering a removal procedure
that cannot be aborted or reversed. Unfortunately, however, the
kernel currently doesn't provide any support for that.
To address that deficiency, introduce support for offline and
online operations that can be performed on devices, respectively,
before a hot-removal and in case when it is necessary (or convenient)
to put a device back online after a successful offline (that has not
been followed by removal). The idea is that the offline will fail
whenever the given device cannot be gracefully removed from the
system and it will not be allowed to use the device after a
successful offline (until a subsequent online) in analogy with the
existing CPU offline/online mechanism.
For now, the offline and online operations are introduced at the
bus type level, as that should be sufficient for the most urgent use
cases (CPUs and memory modules). In the future, however, the
approach may be extended to cover some more complicated device
offline/online scenarios involving device drivers etc.
The lock_device_hotplug() and unlock_device_hotplug() functions are
introduced because subsequent patches need to put larger pieces of
code under device_hotplug_lock to prevent race conditions between
device offline and removal from happening.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Toshi Kani <toshi.kani@hp.com>
2013-05-02 14:15:29 -06:00
|
|
|
char *buf)
|
|
|
|
{
|
|
|
|
bool val;
|
|
|
|
|
driver core / ACPI: Avoid device hot remove locking issues
device_hotplug_lock is held around the acpi_bus_trim() call in
acpi_scan_hot_remove() which generally removes devices (it removes
ACPI device objects at least, but it may also remove "physical"
device objects through .detach() callbacks of ACPI scan handlers).
Thus, potentially, device sysfs attributes are removed under that
lock and to remove those attributes it is necessary to hold the
s_active references of their directory entries for writing.
On the other hand, the execution of a .show() or .store() callback
from a sysfs attribute is carried out with that attribute's s_active
reference held for reading. Consequently, if any device sysfs
attribute that may be removed from within acpi_scan_hot_remove()
through acpi_bus_trim() has a .store() or .show() callback which
acquires device_hotplug_lock, the execution of that callback may
deadlock with the removal of the attribute. [Unfortunately, the
"online" device attribute of CPUs and memory blocks is one of them.]
To avoid such deadlocks, make all of the sysfs attribute callbacks
that need to lock device hotplug, for example store_online(), use
a special function, lock_device_hotplug_sysfs(), to lock device
hotplug and return the result of that function immediately if it is
not zero. This will cause the s_active reference of the directory
entry in question to be released and the syscall to be restarted
if device_hotplug_lock cannot be acquired.
[show_online() actually doesn't need to lock device hotplug, but
it is useful to serialize it with respect to device_offline() and
device_online() for the same device (in case user space attempts to
run them concurrently) which can be done with the help of
device_lock().]
Reported-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Reported-and-tested-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
2013-08-28 13:41:01 -06:00
|
|
|
device_lock(dev);
|
Driver core: Add offline/online device operations
In some cases, graceful hot-removal of devices is not possible,
although in principle the devices in question support hotplug.
For example, that may happen for the last CPU in the system or
for memory modules holding kernel memory.
In those cases it is nice to be able to check if the given device
can be gracefully hot-removed before triggering a removal procedure
that cannot be aborted or reversed. Unfortunately, however, the
kernel currently doesn't provide any support for that.
To address that deficiency, introduce support for offline and
online operations that can be performed on devices, respectively,
before a hot-removal and in case when it is necessary (or convenient)
to put a device back online after a successful offline (that has not
been followed by removal). The idea is that the offline will fail
whenever the given device cannot be gracefully removed from the
system and it will not be allowed to use the device after a
successful offline (until a subsequent online) in analogy with the
existing CPU offline/online mechanism.
For now, the offline and online operations are introduced at the
bus type level, as that should be sufficient for the most urgent use
cases (CPUs and memory modules). In the future, however, the
approach may be extended to cover some more complicated device
offline/online scenarios involving device drivers etc.
The lock_device_hotplug() and unlock_device_hotplug() functions are
introduced because subsequent patches need to put larger pieces of
code under device_hotplug_lock to prevent race conditions between
device offline and removal from happening.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Toshi Kani <toshi.kani@hp.com>
2013-05-02 14:15:29 -06:00
|
|
|
val = !dev->offline;
|
driver core / ACPI: Avoid device hot remove locking issues
device_hotplug_lock is held around the acpi_bus_trim() call in
acpi_scan_hot_remove() which generally removes devices (it removes
ACPI device objects at least, but it may also remove "physical"
device objects through .detach() callbacks of ACPI scan handlers).
Thus, potentially, device sysfs attributes are removed under that
lock and to remove those attributes it is necessary to hold the
s_active references of their directory entries for writing.
On the other hand, the execution of a .show() or .store() callback
from a sysfs attribute is carried out with that attribute's s_active
reference held for reading. Consequently, if any device sysfs
attribute that may be removed from within acpi_scan_hot_remove()
through acpi_bus_trim() has a .store() or .show() callback which
acquires device_hotplug_lock, the execution of that callback may
deadlock with the removal of the attribute. [Unfortunately, the
"online" device attribute of CPUs and memory blocks is one of them.]
To avoid such deadlocks, make all of the sysfs attribute callbacks
that need to lock device hotplug, for example store_online(), use
a special function, lock_device_hotplug_sysfs(), to lock device
hotplug and return the result of that function immediately if it is
not zero. This will cause the s_active reference of the directory
entry in question to be released and the syscall to be restarted
if device_hotplug_lock cannot be acquired.
[show_online() actually doesn't need to lock device hotplug, but
it is useful to serialize it with respect to device_offline() and
device_online() for the same device (in case user space attempts to
run them concurrently) which can be done with the help of
device_lock().]
Reported-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Reported-and-tested-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
2013-08-28 13:41:01 -06:00
|
|
|
device_unlock(dev);
|
Driver core: Add offline/online device operations
In some cases, graceful hot-removal of devices is not possible,
although in principle the devices in question support hotplug.
For example, that may happen for the last CPU in the system or
for memory modules holding kernel memory.
In those cases it is nice to be able to check if the given device
can be gracefully hot-removed before triggering a removal procedure
that cannot be aborted or reversed. Unfortunately, however, the
kernel currently doesn't provide any support for that.
To address that deficiency, introduce support for offline and
online operations that can be performed on devices, respectively,
before a hot-removal and in case when it is necessary (or convenient)
to put a device back online after a successful offline (that has not
been followed by removal). The idea is that the offline will fail
whenever the given device cannot be gracefully removed from the
system and it will not be allowed to use the device after a
successful offline (until a subsequent online) in analogy with the
existing CPU offline/online mechanism.
For now, the offline and online operations are introduced at the
bus type level, as that should be sufficient for the most urgent use
cases (CPUs and memory modules). In the future, however, the
approach may be extended to cover some more complicated device
offline/online scenarios involving device drivers etc.
The lock_device_hotplug() and unlock_device_hotplug() functions are
introduced because subsequent patches need to put larger pieces of
code under device_hotplug_lock to prevent race conditions between
device offline and removal from happening.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Toshi Kani <toshi.kani@hp.com>
2013-05-02 14:15:29 -06:00
|
|
|
return sprintf(buf, "%u\n", val);
|
|
|
|
}
|
|
|
|
|
2013-08-23 18:07:26 -06:00
|
|
|
static ssize_t online_store(struct device *dev, struct device_attribute *attr,
|
Driver core: Add offline/online device operations
In some cases, graceful hot-removal of devices is not possible,
although in principle the devices in question support hotplug.
For example, that may happen for the last CPU in the system or
for memory modules holding kernel memory.
In those cases it is nice to be able to check if the given device
can be gracefully hot-removed before triggering a removal procedure
that cannot be aborted or reversed. Unfortunately, however, the
kernel currently doesn't provide any support for that.
To address that deficiency, introduce support for offline and
online operations that can be performed on devices, respectively,
before a hot-removal and in case when it is necessary (or convenient)
to put a device back online after a successful offline (that has not
been followed by removal). The idea is that the offline will fail
whenever the given device cannot be gracefully removed from the
system and it will not be allowed to use the device after a
successful offline (until a subsequent online) in analogy with the
existing CPU offline/online mechanism.
For now, the offline and online operations are introduced at the
bus type level, as that should be sufficient for the most urgent use
cases (CPUs and memory modules). In the future, however, the
approach may be extended to cover some more complicated device
offline/online scenarios involving device drivers etc.
The lock_device_hotplug() and unlock_device_hotplug() functions are
introduced because subsequent patches need to put larger pieces of
code under device_hotplug_lock to prevent race conditions between
device offline and removal from happening.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Toshi Kani <toshi.kani@hp.com>
2013-05-02 14:15:29 -06:00
|
|
|
const char *buf, size_t count)
|
|
|
|
{
|
|
|
|
bool val;
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
ret = strtobool(buf, &val);
|
|
|
|
if (ret < 0)
|
|
|
|
return ret;
|
|
|
|
|
driver core / ACPI: Avoid device hot remove locking issues
device_hotplug_lock is held around the acpi_bus_trim() call in
acpi_scan_hot_remove() which generally removes devices (it removes
ACPI device objects at least, but it may also remove "physical"
device objects through .detach() callbacks of ACPI scan handlers).
Thus, potentially, device sysfs attributes are removed under that
lock and to remove those attributes it is necessary to hold the
s_active references of their directory entries for writing.
On the other hand, the execution of a .show() or .store() callback
from a sysfs attribute is carried out with that attribute's s_active
reference held for reading. Consequently, if any device sysfs
attribute that may be removed from within acpi_scan_hot_remove()
through acpi_bus_trim() has a .store() or .show() callback which
acquires device_hotplug_lock, the execution of that callback may
deadlock with the removal of the attribute. [Unfortunately, the
"online" device attribute of CPUs and memory blocks is one of them.]
To avoid such deadlocks, make all of the sysfs attribute callbacks
that need to lock device hotplug, for example store_online(), use
a special function, lock_device_hotplug_sysfs(), to lock device
hotplug and return the result of that function immediately if it is
not zero. This will cause the s_active reference of the directory
entry in question to be released and the syscall to be restarted
if device_hotplug_lock cannot be acquired.
[show_online() actually doesn't need to lock device hotplug, but
it is useful to serialize it with respect to device_offline() and
device_online() for the same device (in case user space attempts to
run them concurrently) which can be done with the help of
device_lock().]
Reported-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Reported-and-tested-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
2013-08-28 13:41:01 -06:00
|
|
|
ret = lock_device_hotplug_sysfs();
|
|
|
|
if (ret)
|
|
|
|
return ret;
|
|
|
|
|
Driver core: Add offline/online device operations
In some cases, graceful hot-removal of devices is not possible,
although in principle the devices in question support hotplug.
For example, that may happen for the last CPU in the system or
for memory modules holding kernel memory.
In those cases it is nice to be able to check if the given device
can be gracefully hot-removed before triggering a removal procedure
that cannot be aborted or reversed. Unfortunately, however, the
kernel currently doesn't provide any support for that.
To address that deficiency, introduce support for offline and
online operations that can be performed on devices, respectively,
before a hot-removal and in case when it is necessary (or convenient)
to put a device back online after a successful offline (that has not
been followed by removal). The idea is that the offline will fail
whenever the given device cannot be gracefully removed from the
system and it will not be allowed to use the device after a
successful offline (until a subsequent online) in analogy with the
existing CPU offline/online mechanism.
For now, the offline and online operations are introduced at the
bus type level, as that should be sufficient for the most urgent use
cases (CPUs and memory modules). In the future, however, the
approach may be extended to cover some more complicated device
offline/online scenarios involving device drivers etc.
The lock_device_hotplug() and unlock_device_hotplug() functions are
introduced because subsequent patches need to put larger pieces of
code under device_hotplug_lock to prevent race conditions between
device offline and removal from happening.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Toshi Kani <toshi.kani@hp.com>
2013-05-02 14:15:29 -06:00
|
|
|
ret = val ? device_online(dev) : device_offline(dev);
|
|
|
|
unlock_device_hotplug();
|
|
|
|
return ret < 0 ? ret : count;
|
|
|
|
}
|
2013-08-23 18:07:26 -06:00
|
|
|
static DEVICE_ATTR_RW(online);
|
Driver core: Add offline/online device operations
In some cases, graceful hot-removal of devices is not possible,
although in principle the devices in question support hotplug.
For example, that may happen for the last CPU in the system or
for memory modules holding kernel memory.
In those cases it is nice to be able to check if the given device
can be gracefully hot-removed before triggering a removal procedure
that cannot be aborted or reversed. Unfortunately, however, the
kernel currently doesn't provide any support for that.
To address that deficiency, introduce support for offline and
online operations that can be performed on devices, respectively,
before a hot-removal and in case when it is necessary (or convenient)
to put a device back online after a successful offline (that has not
been followed by removal). The idea is that the offline will fail
whenever the given device cannot be gracefully removed from the
system and it will not be allowed to use the device after a
successful offline (until a subsequent online) in analogy with the
existing CPU offline/online mechanism.
For now, the offline and online operations are introduced at the
bus type level, as that should be sufficient for the most urgent use
cases (CPUs and memory modules). In the future, however, the
approach may be extended to cover some more complicated device
offline/online scenarios involving device drivers etc.
The lock_device_hotplug() and unlock_device_hotplug() functions are
introduced because subsequent patches need to put larger pieces of
code under device_hotplug_lock to prevent race conditions between
device offline and removal from happening.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Toshi Kani <toshi.kani@hp.com>
2013-05-02 14:15:29 -06:00
|
|
|
|
2013-08-08 16:22:55 -06:00
|
|
|
int device_add_groups(struct device *dev, const struct attribute_group **groups)
|
2007-03-09 23:37:34 -07:00
|
|
|
{
|
2013-08-21 14:47:50 -06:00
|
|
|
return sysfs_create_groups(&dev->kobj, groups);
|
2006-06-27 01:06:09 -06:00
|
|
|
}
|
|
|
|
|
2013-08-08 16:22:55 -06:00
|
|
|
void device_remove_groups(struct device *dev,
|
|
|
|
const struct attribute_group **groups)
|
2006-06-27 01:06:09 -06:00
|
|
|
{
|
2013-08-21 14:47:50 -06:00
|
|
|
sysfs_remove_groups(&dev->kobj, groups);
|
2006-06-27 01:06:09 -06:00
|
|
|
}
|
|
|
|
|
2006-06-28 17:19:58 -06:00
|
|
|
static int device_add_attrs(struct device *dev)
|
|
|
|
{
|
|
|
|
struct class *class = dev->class;
|
2011-03-28 10:12:52 -06:00
|
|
|
const struct device_type *type = dev->type;
|
2007-03-09 23:37:34 -07:00
|
|
|
int error;
|
2006-06-28 17:19:58 -06:00
|
|
|
|
2007-03-09 23:37:34 -07:00
|
|
|
if (class) {
|
2013-07-14 17:05:58 -06:00
|
|
|
error = device_add_groups(dev, class->dev_groups);
|
2006-10-07 13:54:55 -06:00
|
|
|
if (error)
|
2007-03-09 23:37:34 -07:00
|
|
|
return error;
|
2006-06-28 17:19:58 -06:00
|
|
|
}
|
2006-10-07 13:54:55 -06:00
|
|
|
|
2007-03-09 23:37:34 -07:00
|
|
|
if (type) {
|
|
|
|
error = device_add_groups(dev, type->groups);
|
2006-10-07 13:54:55 -06:00
|
|
|
if (error)
|
2013-10-05 19:19:30 -06:00
|
|
|
goto err_remove_class_groups;
|
2006-10-07 13:54:55 -06:00
|
|
|
}
|
|
|
|
|
2007-03-09 23:37:34 -07:00
|
|
|
error = device_add_groups(dev, dev->groups);
|
|
|
|
if (error)
|
|
|
|
goto err_remove_type_groups;
|
|
|
|
|
Driver core: Add offline/online device operations
In some cases, graceful hot-removal of devices is not possible,
although in principle the devices in question support hotplug.
For example, that may happen for the last CPU in the system or
for memory modules holding kernel memory.
In those cases it is nice to be able to check if the given device
can be gracefully hot-removed before triggering a removal procedure
that cannot be aborted or reversed. Unfortunately, however, the
kernel currently doesn't provide any support for that.
To address that deficiency, introduce support for offline and
online operations that can be performed on devices, respectively,
before a hot-removal and in case when it is necessary (or convenient)
to put a device back online after a successful offline (that has not
been followed by removal). The idea is that the offline will fail
whenever the given device cannot be gracefully removed from the
system and it will not be allowed to use the device after a
successful offline (until a subsequent online) in analogy with the
existing CPU offline/online mechanism.
For now, the offline and online operations are introduced at the
bus type level, as that should be sufficient for the most urgent use
cases (CPUs and memory modules). In the future, however, the
approach may be extended to cover some more complicated device
offline/online scenarios involving device drivers etc.
The lock_device_hotplug() and unlock_device_hotplug() functions are
introduced because subsequent patches need to put larger pieces of
code under device_hotplug_lock to prevent race conditions between
device offline and removal from happening.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Toshi Kani <toshi.kani@hp.com>
2013-05-02 14:15:29 -06:00
|
|
|
if (device_supports_offline(dev) && !dev->offline_disabled) {
|
2013-08-23 18:07:26 -06:00
|
|
|
error = device_create_file(dev, &dev_attr_online);
|
Driver core: Add offline/online device operations
In some cases, graceful hot-removal of devices is not possible,
although in principle the devices in question support hotplug.
For example, that may happen for the last CPU in the system or
for memory modules holding kernel memory.
In those cases it is nice to be able to check if the given device
can be gracefully hot-removed before triggering a removal procedure
that cannot be aborted or reversed. Unfortunately, however, the
kernel currently doesn't provide any support for that.
To address that deficiency, introduce support for offline and
online operations that can be performed on devices, respectively,
before a hot-removal and in case when it is necessary (or convenient)
to put a device back online after a successful offline (that has not
been followed by removal). The idea is that the offline will fail
whenever the given device cannot be gracefully removed from the
system and it will not be allowed to use the device after a
successful offline (until a subsequent online) in analogy with the
existing CPU offline/online mechanism.
For now, the offline and online operations are introduced at the
bus type level, as that should be sufficient for the most urgent use
cases (CPUs and memory modules). In the future, however, the
approach may be extended to cover some more complicated device
offline/online scenarios involving device drivers etc.
The lock_device_hotplug() and unlock_device_hotplug() functions are
introduced because subsequent patches need to put larger pieces of
code under device_hotplug_lock to prevent race conditions between
device offline and removal from happening.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Toshi Kani <toshi.kani@hp.com>
2013-05-02 14:15:29 -06:00
|
|
|
if (error)
|
2013-12-11 22:11:02 -07:00
|
|
|
goto err_remove_dev_groups;
|
Driver core: Add offline/online device operations
In some cases, graceful hot-removal of devices is not possible,
although in principle the devices in question support hotplug.
For example, that may happen for the last CPU in the system or
for memory modules holding kernel memory.
In those cases it is nice to be able to check if the given device
can be gracefully hot-removed before triggering a removal procedure
that cannot be aborted or reversed. Unfortunately, however, the
kernel currently doesn't provide any support for that.
To address that deficiency, introduce support for offline and
online operations that can be performed on devices, respectively,
before a hot-removal and in case when it is necessary (or convenient)
to put a device back online after a successful offline (that has not
been followed by removal). The idea is that the offline will fail
whenever the given device cannot be gracefully removed from the
system and it will not be allowed to use the device after a
successful offline (until a subsequent online) in analogy with the
existing CPU offline/online mechanism.
For now, the offline and online operations are introduced at the
bus type level, as that should be sufficient for the most urgent use
cases (CPUs and memory modules). In the future, however, the
approach may be extended to cover some more complicated device
offline/online scenarios involving device drivers etc.
The lock_device_hotplug() and unlock_device_hotplug() functions are
introduced because subsequent patches need to put larger pieces of
code under device_hotplug_lock to prevent race conditions between
device offline and removal from happening.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Toshi Kani <toshi.kani@hp.com>
2013-05-02 14:15:29 -06:00
|
|
|
}
|
|
|
|
|
2007-03-09 23:37:34 -07:00
|
|
|
return 0;
|
|
|
|
|
2013-12-11 22:11:02 -07:00
|
|
|
err_remove_dev_groups:
|
|
|
|
device_remove_groups(dev, dev->groups);
|
2007-03-09 23:37:34 -07:00
|
|
|
err_remove_type_groups:
|
|
|
|
if (type)
|
|
|
|
device_remove_groups(dev, type->groups);
|
2013-07-14 17:05:58 -06:00
|
|
|
err_remove_class_groups:
|
|
|
|
if (class)
|
|
|
|
device_remove_groups(dev, class->dev_groups);
|
2007-03-09 23:37:34 -07:00
|
|
|
|
2006-06-28 17:19:58 -06:00
|
|
|
return error;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void device_remove_attrs(struct device *dev)
|
|
|
|
{
|
|
|
|
struct class *class = dev->class;
|
2011-03-28 10:12:52 -06:00
|
|
|
const struct device_type *type = dev->type;
|
2006-06-28 17:19:58 -06:00
|
|
|
|
2013-08-23 18:07:26 -06:00
|
|
|
device_remove_file(dev, &dev_attr_online);
|
2007-03-09 23:37:34 -07:00
|
|
|
device_remove_groups(dev, dev->groups);
|
2006-10-07 13:54:55 -06:00
|
|
|
|
2007-03-09 23:37:34 -07:00
|
|
|
if (type)
|
|
|
|
device_remove_groups(dev, type->groups);
|
|
|
|
|
2013-10-05 19:19:30 -06:00
|
|
|
if (class)
|
2013-07-14 17:05:58 -06:00
|
|
|
device_remove_groups(dev, class->dev_groups);
|
2006-06-28 17:19:58 -06:00
|
|
|
}
|
|
|
|
|
2013-08-23 18:07:26 -06:00
|
|
|
static ssize_t dev_show(struct device *dev, struct device_attribute *attr,
|
2006-06-14 13:14:34 -06:00
|
|
|
char *buf)
|
|
|
|
{
|
|
|
|
return print_dev_t(buf, dev->devt);
|
|
|
|
}
|
2013-08-23 18:07:26 -06:00
|
|
|
static DEVICE_ATTR_RO(dev);
|
2007-06-13 12:45:17 -06:00
|
|
|
|
2011-12-14 15:29:38 -07:00
|
|
|
/* /sys/devices/ */
|
2007-11-01 09:29:06 -06:00
|
|
|
struct kset *devices_kset;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* device_create_file - create sysfs attribute file for device.
|
|
|
|
* @dev: device.
|
|
|
|
* @attr: device attribute descriptor.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2009-12-18 06:34:19 -07:00
|
|
|
int device_create_file(struct device *dev,
|
|
|
|
const struct device_attribute *attr)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
|
|
|
int error = 0;
|
2013-02-20 01:31:42 -07:00
|
|
|
|
|
|
|
if (dev) {
|
|
|
|
WARN(((attr->attr.mode & S_IWUGO) && !attr->store),
|
2013-05-16 00:31:30 -06:00
|
|
|
"Attribute %s: write permission without 'store'\n",
|
|
|
|
attr->attr.name);
|
2013-02-20 01:31:42 -07:00
|
|
|
WARN(((attr->attr.mode & S_IRUGO) && !attr->show),
|
2013-05-16 00:31:30 -06:00
|
|
|
"Attribute %s: read permission without 'show'\n",
|
|
|
|
attr->attr.name);
|
2005-04-16 16:20:36 -06:00
|
|
|
error = sysfs_create_file(&dev->kobj, &attr->attr);
|
2013-02-20 01:31:42 -07:00
|
|
|
}
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
return error;
|
|
|
|
}
|
2013-07-21 18:41:14 -06:00
|
|
|
EXPORT_SYMBOL_GPL(device_create_file);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* device_remove_file - remove sysfs attribute file.
|
|
|
|
* @dev: device.
|
|
|
|
* @attr: device attribute descriptor.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2009-12-18 06:34:19 -07:00
|
|
|
void device_remove_file(struct device *dev,
|
|
|
|
const struct device_attribute *attr)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2008-01-31 02:39:38 -07:00
|
|
|
if (dev)
|
2005-04-16 16:20:36 -06:00
|
|
|
sysfs_remove_file(&dev->kobj, &attr->attr);
|
|
|
|
}
|
2013-07-21 18:41:14 -06:00
|
|
|
EXPORT_SYMBOL_GPL(device_remove_file);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
kernfs, sysfs, driver-core: implement kernfs_remove_self() and its wrappers
Sometimes it's necessary to implement a node which wants to delete
nodes including itself. This isn't straightforward because of kernfs
active reference. While a file operation is in progress, an active
reference is held and kernfs_remove() waits for all such references to
drain before completing. For a self-deleting node, this is a deadlock
as kernfs_remove() ends up waiting for an active reference that itself
is sitting on top of.
This currently is worked around in the sysfs layer using
sysfs_schedule_callback() which makes such removals asynchronous.
While it works, it's rather cumbersome and inherently breaks
synchronicity of the operation - the file operation which triggered
the operation may complete before the removal is finished (or even
started) and the removal may fail asynchronously. If a removal
operation is immmediately followed by another operation which expects
the specific name to be available (e.g. removal followed by rename
onto the same name), there's no way to make the latter operation
reliable.
The thing is there's no inherent reason for this to be asynchrnous.
All that's necessary to do this synchronous is a dedicated operation
which drops its own active ref and deactivates self. This patch
implements kernfs_remove_self() and its wrappers in sysfs and driver
core. kernfs_remove_self() is to be called from one of the file
operations, drops the active ref the task is holding, removes the self
node, and restores active ref to the dead node so that the ref is
balanced afterwards. __kernfs_remove() is updated so that it takes an
early exit if the target node is already fully removed so that the
active ref restored by kernfs_remove_self() after removal doesn't
confuse the deactivation path.
This makes implementing self-deleting nodes very easy. The normal
removal path doesn't even need to be changed to use
kernfs_remove_self() for the self-deleting node. The method can
invoke kernfs_remove_self() on itself before proceeding the normal
removal path. kernfs_remove() invoked on the node by the normal
deletion path will simply be ignored.
This will replace sysfs_schedule_callback(). A subtle feature of
sysfs_schedule_callback() is that it collapses multiple invocations -
even if multiple removals are triggered, the removal callback is run
only once. An equivalent effect can be achieved by testing the return
value of kernfs_remove_self() - only the one which gets %true return
value should proceed with actual deletion. All other instances of
kernfs_remove_self() will wait till the enclosing kernfs operation
which invoked the winning instance of kernfs_remove_self() finishes
and then return %false. This trivially makes all users of
kernfs_remove_self() automatically show correct synchronous behavior
even when there are multiple concurrent operations - all "echo 1 >
delete" instances will finish only after the whole operation is
completed by one of the instances.
Note that manipulation of active ref is implemented in separate public
functions - kernfs_[un]break_active_protection().
kernfs_remove_self() is the only user at the moment but this will be
used to cater to more complex cases.
v2: For !CONFIG_SYSFS, dummy version kernfs_remove_self() was missing
and sysfs_remove_file_self() had incorrect return type. Fix it.
Reported by kbuild test bot.
v3: kernfs_[un]break_active_protection() separated out from
kernfs_remove_self() and exposed as public API.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-03 12:03:01 -07:00
|
|
|
/**
|
|
|
|
* device_remove_file_self - remove sysfs attribute file from its own method.
|
|
|
|
* @dev: device.
|
|
|
|
* @attr: device attribute descriptor.
|
|
|
|
*
|
|
|
|
* See kernfs_remove_self() for details.
|
|
|
|
*/
|
|
|
|
bool device_remove_file_self(struct device *dev,
|
|
|
|
const struct device_attribute *attr)
|
|
|
|
{
|
|
|
|
if (dev)
|
|
|
|
return sysfs_remove_file_self(&dev->kobj, &attr->attr);
|
|
|
|
else
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(device_remove_file_self);
|
|
|
|
|
2006-09-19 10:39:19 -06:00
|
|
|
/**
|
|
|
|
* device_create_bin_file - create sysfs binary attribute file for device.
|
|
|
|
* @dev: device.
|
|
|
|
* @attr: device binary attribute descriptor.
|
|
|
|
*/
|
2009-12-18 06:34:20 -07:00
|
|
|
int device_create_bin_file(struct device *dev,
|
|
|
|
const struct bin_attribute *attr)
|
2006-09-19 10:39:19 -06:00
|
|
|
{
|
|
|
|
int error = -EINVAL;
|
|
|
|
if (dev)
|
|
|
|
error = sysfs_create_bin_file(&dev->kobj, attr);
|
|
|
|
return error;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(device_create_bin_file);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* device_remove_bin_file - remove sysfs binary attribute file
|
|
|
|
* @dev: device.
|
|
|
|
* @attr: device binary attribute descriptor.
|
|
|
|
*/
|
2009-12-18 06:34:20 -07:00
|
|
|
void device_remove_bin_file(struct device *dev,
|
|
|
|
const struct bin_attribute *attr)
|
2006-09-19 10:39:19 -06:00
|
|
|
{
|
|
|
|
if (dev)
|
|
|
|
sysfs_remove_bin_file(&dev->kobj, attr);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(device_remove_bin_file);
|
|
|
|
|
2014-03-25 21:54:57 -06:00
|
|
|
/**
|
|
|
|
* device_schedule_callback_owner - helper to schedule a callback for a device
|
|
|
|
* @dev: device.
|
|
|
|
* @func: callback function to invoke later.
|
|
|
|
* @owner: module owning the callback routine
|
|
|
|
*
|
|
|
|
* Attribute methods must not unregister themselves or their parent device
|
|
|
|
* (which would amount to the same thing). Attempts to do so will deadlock,
|
|
|
|
* since unregistration is mutually exclusive with driver callbacks.
|
|
|
|
*
|
|
|
|
* Instead methods can call this routine, which will attempt to allocate
|
|
|
|
* and schedule a workqueue request to call back @func with @dev as its
|
|
|
|
* argument in the workqueue's process context. @dev will be pinned until
|
|
|
|
* @func returns.
|
|
|
|
*
|
|
|
|
* This routine is usually called via the inline device_schedule_callback(),
|
|
|
|
* which automatically sets @owner to THIS_MODULE.
|
|
|
|
*
|
|
|
|
* Returns 0 if the request was submitted, -ENOMEM if storage could not
|
|
|
|
* be allocated, -ENODEV if a reference to @owner isn't available.
|
|
|
|
*
|
|
|
|
* NOTE: This routine won't work if CONFIG_SYSFS isn't set! It uses an
|
|
|
|
* underlying sysfs routine (since it is intended for use by attribute
|
|
|
|
* methods), and if sysfs isn't available you'll get nothing but -ENOSYS.
|
|
|
|
*/
|
|
|
|
int device_schedule_callback_owner(struct device *dev,
|
|
|
|
void (*func)(struct device *), struct module *owner)
|
|
|
|
{
|
|
|
|
return sysfs_schedule_callback(&dev->kobj,
|
|
|
|
(void (*)(void *)) func, dev, owner);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(device_schedule_callback_owner);
|
|
|
|
|
2005-09-06 17:56:51 -06:00
|
|
|
static void klist_children_get(struct klist_node *n)
|
|
|
|
{
|
2008-12-16 13:24:56 -07:00
|
|
|
struct device_private *p = to_device_private_parent(n);
|
|
|
|
struct device *dev = p->device;
|
2005-09-06 17:56:51 -06:00
|
|
|
|
|
|
|
get_device(dev);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void klist_children_put(struct klist_node *n)
|
|
|
|
{
|
2008-12-16 13:24:56 -07:00
|
|
|
struct device_private *p = to_device_private_parent(n);
|
|
|
|
struct device *dev = p->device;
|
2005-09-06 17:56:51 -06:00
|
|
|
|
|
|
|
put_device(dev);
|
|
|
|
}
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* device_initialize - init device structure.
|
|
|
|
* @dev: device.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-09-03 10:26:40 -06:00
|
|
|
* This prepares the device for use by other layers by initializing
|
|
|
|
* its fields.
|
2008-01-24 23:50:12 -07:00
|
|
|
* It is the first half of device_register(), if called by
|
2008-09-03 10:26:40 -06:00
|
|
|
* that function, though it can also be called separately, so one
|
|
|
|
* may use @dev's fields. In particular, get_device()/put_device()
|
|
|
|
* may be used for reference counting of @dev after calling this
|
|
|
|
* function.
|
|
|
|
*
|
2012-01-17 09:39:00 -07:00
|
|
|
* All fields in @dev must be initialized by the caller to 0, except
|
|
|
|
* for those explicitly set to some other value. The simplest
|
|
|
|
* approach is to use kzalloc() to allocate the structure containing
|
|
|
|
* @dev.
|
|
|
|
*
|
2008-09-03 10:26:40 -06:00
|
|
|
* NOTE: Use put_device() to give up your reference instead of freeing
|
|
|
|
* @dev directly once you have called this function.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
|
|
|
void device_initialize(struct device *dev)
|
|
|
|
{
|
2007-11-01 09:29:06 -06:00
|
|
|
dev->kobj.kset = devices_kset;
|
2007-12-17 23:05:35 -07:00
|
|
|
kobject_init(&dev->kobj, &device_ktype);
|
2005-04-16 16:20:36 -06:00
|
|
|
INIT_LIST_HEAD(&dev->dma_pools);
|
2010-01-29 13:39:02 -07:00
|
|
|
mutex_init(&dev->mutex);
|
2010-03-18 18:37:42 -06:00
|
|
|
lockdep_set_novalidate_class(&dev->mutex);
|
devres: device resource management
Implement device resource management, in short, devres. A device
driver can allocate arbirary size of devres data which is associated
with a release function. On driver detach, release function is
invoked on the devres data, then, devres data is freed.
devreses are typed by associated release functions. Some devreses are
better represented by single instance of the type while others need
multiple instances sharing the same release function. Both usages are
supported.
devreses can be grouped using devres group such that a device driver
can easily release acquired resources halfway through initialization
or selectively release resources (e.g. resources for port 1 out of 4
ports).
This patch adds devres core including documentation and the following
managed interfaces.
* alloc/free : devm_kzalloc(), devm_kzfree()
* IO region : devm_request_region(), devm_release_region()
* IRQ : devm_request_irq(), devm_free_irq()
* DMA : dmam_alloc_coherent(), dmam_free_coherent(),
dmam_declare_coherent_memory(), dmam_pool_create(),
dmam_pool_destroy()
* PCI : pcim_enable_device(), pcim_pin_device(), pci_is_managed()
* iomap : devm_ioport_map(), devm_ioport_unmap(), devm_ioremap(),
devm_ioremap_nocache(), devm_iounmap(), pcim_iomap_table(),
pcim_iomap(), pcim_iounmap()
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-20 00:00:26 -07:00
|
|
|
spin_lock_init(&dev->devres_lock);
|
|
|
|
INIT_LIST_HEAD(&dev->devres_head);
|
2008-08-07 11:06:12 -06:00
|
|
|
device_pm_init(dev);
|
2006-12-06 21:32:33 -07:00
|
|
|
set_dev_node(dev, -1);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2013-07-21 18:41:14 -06:00
|
|
|
EXPORT_SYMBOL_GPL(device_initialize);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2013-03-12 12:30:05 -06:00
|
|
|
struct kobject *virtual_device_parent(struct device *dev)
|
2006-10-23 11:40:54 -06:00
|
|
|
{
|
2007-03-13 20:25:56 -06:00
|
|
|
static struct kobject *virtual_dir = NULL;
|
2006-10-23 11:40:54 -06:00
|
|
|
|
2007-03-13 20:25:56 -06:00
|
|
|
if (!virtual_dir)
|
2007-11-05 23:24:43 -07:00
|
|
|
virtual_dir = kobject_create_and_add("virtual",
|
2007-11-01 09:29:06 -06:00
|
|
|
&devices_kset->kobj);
|
2006-10-23 11:40:54 -06:00
|
|
|
|
2007-03-13 20:25:56 -06:00
|
|
|
return virtual_dir;
|
2006-10-23 11:40:54 -06:00
|
|
|
}
|
|
|
|
|
2010-03-30 12:31:25 -06:00
|
|
|
struct class_dir {
|
|
|
|
struct kobject kobj;
|
|
|
|
struct class *class;
|
|
|
|
};
|
|
|
|
|
|
|
|
#define to_class_dir(obj) container_of(obj, struct class_dir, kobj)
|
|
|
|
|
|
|
|
static void class_dir_release(struct kobject *kobj)
|
|
|
|
{
|
|
|
|
struct class_dir *dir = to_class_dir(kobj);
|
|
|
|
kfree(dir);
|
|
|
|
}
|
|
|
|
|
|
|
|
static const
|
|
|
|
struct kobj_ns_type_operations *class_dir_child_ns_type(struct kobject *kobj)
|
2006-10-23 17:37:58 -06:00
|
|
|
{
|
2010-03-30 12:31:25 -06:00
|
|
|
struct class_dir *dir = to_class_dir(kobj);
|
|
|
|
return dir->class->ns_type;
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct kobj_type class_dir_ktype = {
|
|
|
|
.release = class_dir_release,
|
|
|
|
.sysfs_ops = &kobj_sysfs_ops,
|
|
|
|
.child_ns_type = class_dir_child_ns_type
|
|
|
|
};
|
|
|
|
|
|
|
|
static struct kobject *
|
|
|
|
class_dir_create_and_add(struct class *class, struct kobject *parent_kobj)
|
|
|
|
{
|
|
|
|
struct class_dir *dir;
|
2007-11-05 23:24:43 -07:00
|
|
|
int retval;
|
|
|
|
|
2010-03-30 12:31:25 -06:00
|
|
|
dir = kzalloc(sizeof(*dir), GFP_KERNEL);
|
|
|
|
if (!dir)
|
|
|
|
return NULL;
|
|
|
|
|
|
|
|
dir->class = class;
|
|
|
|
kobject_init(&dir->kobj, &class_dir_ktype);
|
|
|
|
|
2010-11-15 15:13:18 -07:00
|
|
|
dir->kobj.kset = &class->p->glue_dirs;
|
2010-03-30 12:31:25 -06:00
|
|
|
|
|
|
|
retval = kobject_add(&dir->kobj, parent_kobj, "%s", class->name);
|
|
|
|
if (retval < 0) {
|
|
|
|
kobject_put(&dir->kobj);
|
|
|
|
return NULL;
|
|
|
|
}
|
|
|
|
return &dir->kobj;
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
static struct kobject *get_device_parent(struct device *dev,
|
|
|
|
struct device *parent)
|
|
|
|
{
|
2007-03-13 20:25:56 -06:00
|
|
|
if (dev->class) {
|
2010-02-05 01:57:02 -07:00
|
|
|
static DEFINE_MUTEX(gdp_mutex);
|
2007-03-13 20:25:56 -06:00
|
|
|
struct kobject *kobj = NULL;
|
|
|
|
struct kobject *parent_kobj;
|
|
|
|
struct kobject *k;
|
|
|
|
|
2010-09-24 15:36:49 -06:00
|
|
|
#ifdef CONFIG_BLOCK
|
2010-09-04 23:33:14 -06:00
|
|
|
/* block disks show up in /sys/block */
|
2010-09-08 08:54:17 -06:00
|
|
|
if (sysfs_deprecated && dev->class == &block_class) {
|
2010-09-04 23:33:14 -06:00
|
|
|
if (parent && parent->class == &block_class)
|
|
|
|
return &parent->kobj;
|
2010-11-15 15:13:18 -07:00
|
|
|
return &block_class.p->subsys.kobj;
|
2010-09-04 23:33:14 -06:00
|
|
|
}
|
2010-09-24 15:36:49 -06:00
|
|
|
#endif
|
2010-09-08 08:54:17 -06:00
|
|
|
|
2007-03-13 20:25:56 -06:00
|
|
|
/*
|
|
|
|
* If we have no parent, we live in "virtual".
|
2007-12-18 17:40:42 -07:00
|
|
|
* Class-devices with a non class-device as parent, live
|
|
|
|
* in a "glue" directory to prevent namespace collisions.
|
2007-03-13 20:25:56 -06:00
|
|
|
*/
|
|
|
|
if (parent == NULL)
|
|
|
|
parent_kobj = virtual_device_parent(dev);
|
2010-07-24 23:43:35 -06:00
|
|
|
else if (parent->class && !dev->class->ns_type)
|
2007-03-13 20:25:56 -06:00
|
|
|
return &parent->kobj;
|
|
|
|
else
|
|
|
|
parent_kobj = &parent->kobj;
|
|
|
|
|
2010-02-05 01:57:02 -07:00
|
|
|
mutex_lock(&gdp_mutex);
|
|
|
|
|
2007-03-13 20:25:56 -06:00
|
|
|
/* find our class-directory at the parent and reference it */
|
2010-11-15 15:13:18 -07:00
|
|
|
spin_lock(&dev->class->p->glue_dirs.list_lock);
|
|
|
|
list_for_each_entry(k, &dev->class->p->glue_dirs.list, entry)
|
2007-03-13 20:25:56 -06:00
|
|
|
if (k->parent == parent_kobj) {
|
|
|
|
kobj = kobject_get(k);
|
|
|
|
break;
|
|
|
|
}
|
2010-11-15 15:13:18 -07:00
|
|
|
spin_unlock(&dev->class->p->glue_dirs.list_lock);
|
2010-02-05 01:57:02 -07:00
|
|
|
if (kobj) {
|
|
|
|
mutex_unlock(&gdp_mutex);
|
2007-03-13 20:25:56 -06:00
|
|
|
return kobj;
|
2010-02-05 01:57:02 -07:00
|
|
|
}
|
2007-03-13 20:25:56 -06:00
|
|
|
|
|
|
|
/* or create a new class-directory at the parent device */
|
2010-03-30 12:31:25 -06:00
|
|
|
k = class_dir_create_and_add(dev->class, parent_kobj);
|
2007-12-18 17:40:42 -07:00
|
|
|
/* do not emit an uevent for this simple "glue" directory */
|
2010-02-05 01:57:02 -07:00
|
|
|
mutex_unlock(&gdp_mutex);
|
2007-11-05 23:24:43 -07:00
|
|
|
return k;
|
2007-03-13 20:25:56 -06:00
|
|
|
}
|
|
|
|
|
2011-12-14 15:29:38 -07:00
|
|
|
/* subsystems can specify a default root directory for their devices */
|
|
|
|
if (!parent && dev->bus && dev->bus->dev_root)
|
|
|
|
return &dev->bus->dev_root->kobj;
|
|
|
|
|
2007-03-13 20:25:56 -06:00
|
|
|
if (parent)
|
2007-01-08 12:16:44 -07:00
|
|
|
return &parent->kobj;
|
|
|
|
return NULL;
|
|
|
|
}
|
2007-11-21 09:29:15 -07:00
|
|
|
|
2008-01-21 08:09:44 -07:00
|
|
|
static void cleanup_glue_dir(struct device *dev, struct kobject *glue_dir)
|
2007-11-21 09:29:15 -07:00
|
|
|
{
|
2007-12-18 17:40:42 -07:00
|
|
|
/* see if we live in a "glue" directory */
|
2008-02-27 07:38:23 -07:00
|
|
|
if (!glue_dir || !dev->class ||
|
2010-11-15 15:13:18 -07:00
|
|
|
glue_dir->kset != &dev->class->p->glue_dirs)
|
2007-11-21 09:29:15 -07:00
|
|
|
return;
|
|
|
|
|
2007-12-18 17:40:42 -07:00
|
|
|
kobject_put(glue_dir);
|
2007-11-21 09:29:15 -07:00
|
|
|
}
|
2008-01-21 08:09:44 -07:00
|
|
|
|
|
|
|
static void cleanup_device_parent(struct device *dev)
|
|
|
|
{
|
|
|
|
cleanup_glue_dir(dev, dev->kobj.parent);
|
|
|
|
}
|
2007-03-13 20:25:56 -06:00
|
|
|
|
2007-07-18 02:43:47 -06:00
|
|
|
static int device_add_class_symlinks(struct device *dev)
|
|
|
|
{
|
|
|
|
int error;
|
|
|
|
|
|
|
|
if (!dev->class)
|
|
|
|
return 0;
|
2007-11-21 09:29:15 -07:00
|
|
|
|
2008-05-28 10:28:39 -06:00
|
|
|
error = sysfs_create_link(&dev->kobj,
|
2010-11-15 15:13:18 -07:00
|
|
|
&dev->class->p->subsys.kobj,
|
2007-07-18 02:43:47 -06:00
|
|
|
"subsystem");
|
|
|
|
if (error)
|
|
|
|
goto out;
|
2007-11-21 09:29:15 -07:00
|
|
|
|
2008-01-27 13:12:43 -07:00
|
|
|
if (dev->parent && device_is_not_partition(dev)) {
|
2010-09-04 23:33:14 -06:00
|
|
|
error = sysfs_create_link(&dev->kobj, &dev->parent->kobj,
|
2007-09-18 23:46:50 -06:00
|
|
|
"device");
|
|
|
|
if (error)
|
2010-09-04 23:33:14 -06:00
|
|
|
goto out_subsys;
|
2007-07-18 02:43:47 -06:00
|
|
|
}
|
|
|
|
|
2010-09-24 15:36:49 -06:00
|
|
|
#ifdef CONFIG_BLOCK
|
2010-09-04 23:33:14 -06:00
|
|
|
/* /sys/block has directories and does not need symlinks */
|
2010-09-08 08:54:17 -06:00
|
|
|
if (sysfs_deprecated && dev->class == &block_class)
|
2010-09-04 23:33:14 -06:00
|
|
|
return 0;
|
2010-09-24 15:36:49 -06:00
|
|
|
#endif
|
2010-09-04 23:33:14 -06:00
|
|
|
|
2007-11-21 09:29:15 -07:00
|
|
|
/* link in the class directory pointing to the device */
|
2010-11-15 15:13:18 -07:00
|
|
|
error = sysfs_create_link(&dev->class->p->subsys.kobj,
|
2008-10-29 18:36:48 -06:00
|
|
|
&dev->kobj, dev_name(dev));
|
2007-11-21 09:29:15 -07:00
|
|
|
if (error)
|
2010-09-04 23:33:14 -06:00
|
|
|
goto out_device;
|
2007-11-21 09:29:15 -07:00
|
|
|
|
|
|
|
return 0;
|
|
|
|
|
2010-09-04 23:33:14 -06:00
|
|
|
out_device:
|
|
|
|
sysfs_remove_link(&dev->kobj, "device");
|
2007-11-21 09:29:15 -07:00
|
|
|
|
2007-07-18 02:43:47 -06:00
|
|
|
out_subsys:
|
|
|
|
sysfs_remove_link(&dev->kobj, "subsystem");
|
|
|
|
out:
|
|
|
|
return error;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void device_remove_class_symlinks(struct device *dev)
|
|
|
|
{
|
|
|
|
if (!dev->class)
|
|
|
|
return;
|
2007-11-21 09:29:15 -07:00
|
|
|
|
2008-01-27 13:12:43 -07:00
|
|
|
if (dev->parent && device_is_not_partition(dev))
|
2007-11-21 09:29:15 -07:00
|
|
|
sysfs_remove_link(&dev->kobj, "device");
|
2007-07-18 02:43:47 -06:00
|
|
|
sysfs_remove_link(&dev->kobj, "subsystem");
|
2010-09-24 15:36:49 -06:00
|
|
|
#ifdef CONFIG_BLOCK
|
2010-09-08 08:54:17 -06:00
|
|
|
if (sysfs_deprecated && dev->class == &block_class)
|
2010-09-04 23:33:14 -06:00
|
|
|
return;
|
2010-09-24 15:36:49 -06:00
|
|
|
#endif
|
2010-11-15 15:13:18 -07:00
|
|
|
sysfs_delete_link(&dev->class->p->subsys.kobj, &dev->kobj, dev_name(dev));
|
2007-07-18 02:43:47 -06:00
|
|
|
}
|
|
|
|
|
2008-05-29 18:16:40 -06:00
|
|
|
/**
|
|
|
|
* dev_set_name - set a device name
|
|
|
|
* @dev: device
|
2008-06-04 22:40:43 -06:00
|
|
|
* @fmt: format string for the device's name
|
2008-05-29 18:16:40 -06:00
|
|
|
*/
|
|
|
|
int dev_set_name(struct device *dev, const char *fmt, ...)
|
|
|
|
{
|
|
|
|
va_list vargs;
|
2009-01-25 07:17:37 -07:00
|
|
|
int err;
|
2008-05-29 18:16:40 -06:00
|
|
|
|
|
|
|
va_start(vargs, fmt);
|
2009-01-25 07:17:37 -07:00
|
|
|
err = kobject_set_name_vargs(&dev->kobj, fmt, vargs);
|
2008-05-29 18:16:40 -06:00
|
|
|
va_end(vargs);
|
2009-01-25 07:17:37 -07:00
|
|
|
return err;
|
2008-05-29 18:16:40 -06:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(dev_set_name);
|
|
|
|
|
2008-04-21 11:51:07 -06:00
|
|
|
/**
|
|
|
|
* device_to_dev_kobj - select a /sys/dev/ directory for the device
|
|
|
|
* @dev: device
|
|
|
|
*
|
|
|
|
* By default we select char/ for new entries. Setting class->dev_obj
|
|
|
|
* to NULL prevents an entry from being created. class->dev_kobj must
|
|
|
|
* be set (or cleared) before any devices are registered to the class
|
|
|
|
* otherwise device_create_sys_dev_entry() and
|
2012-04-17 04:12:57 -06:00
|
|
|
* device_remove_sys_dev_entry() will disagree about the presence of
|
|
|
|
* the link.
|
2008-04-21 11:51:07 -06:00
|
|
|
*/
|
|
|
|
static struct kobject *device_to_dev_kobj(struct device *dev)
|
|
|
|
{
|
|
|
|
struct kobject *kobj;
|
|
|
|
|
|
|
|
if (dev->class)
|
|
|
|
kobj = dev->class->dev_kobj;
|
|
|
|
else
|
|
|
|
kobj = sysfs_dev_char_kobj;
|
|
|
|
|
|
|
|
return kobj;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int device_create_sys_dev_entry(struct device *dev)
|
|
|
|
{
|
|
|
|
struct kobject *kobj = device_to_dev_kobj(dev);
|
|
|
|
int error = 0;
|
|
|
|
char devt_str[15];
|
|
|
|
|
|
|
|
if (kobj) {
|
|
|
|
format_dev_t(devt_str, dev->devt);
|
|
|
|
error = sysfs_create_link(kobj, &dev->kobj, devt_str);
|
|
|
|
}
|
|
|
|
|
|
|
|
return error;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void device_remove_sys_dev_entry(struct device *dev)
|
|
|
|
{
|
|
|
|
struct kobject *kobj = device_to_dev_kobj(dev);
|
|
|
|
char devt_str[15];
|
|
|
|
|
|
|
|
if (kobj) {
|
|
|
|
format_dev_t(devt_str, dev->devt);
|
|
|
|
sysfs_remove_link(kobj, devt_str);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2009-05-11 15:16:57 -06:00
|
|
|
int device_private_init(struct device *dev)
|
|
|
|
{
|
|
|
|
dev->p = kzalloc(sizeof(*dev->p), GFP_KERNEL);
|
|
|
|
if (!dev->p)
|
|
|
|
return -ENOMEM;
|
|
|
|
dev->p->device = dev;
|
|
|
|
klist_init(&dev->p->klist_children, klist_children_get,
|
|
|
|
klist_children_put);
|
2012-03-08 13:17:22 -07:00
|
|
|
INIT_LIST_HEAD(&dev->p->deferred_probe);
|
2009-05-11 15:16:57 -06:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* device_add - add device to device hierarchy.
|
|
|
|
* @dev: device.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-01-24 23:50:12 -07:00
|
|
|
* This is part 2 of device_register(), though may be called
|
|
|
|
* separately _iff_ device_initialize() has been called separately.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-09-03 10:26:40 -06:00
|
|
|
* This adds @dev to the kobject hierarchy via kobject_add(), adds it
|
2008-01-24 23:50:12 -07:00
|
|
|
* to the global and sibling lists for the device, then
|
|
|
|
* adds it to the other relevant subsystems of the driver model.
|
2008-09-03 10:26:40 -06:00
|
|
|
*
|
2012-01-17 09:39:00 -07:00
|
|
|
* Do not call this routine or device_register() more than once for
|
|
|
|
* any device structure. The driver model core is not designed to work
|
|
|
|
* with devices that get unregistered and then spring back to life.
|
|
|
|
* (Among other things, it's very hard to guarantee that all references
|
|
|
|
* to the previous incarnation of @dev have been dropped.) Allocate
|
|
|
|
* and register a fresh new struct device instead.
|
|
|
|
*
|
2008-09-03 10:26:40 -06:00
|
|
|
* NOTE: _Never_ directly free @dev after calling this function, even
|
|
|
|
* if it returned an error! Always use put_device() to give up your
|
|
|
|
* reference instead.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
|
|
|
int device_add(struct device *dev)
|
|
|
|
{
|
|
|
|
struct device *parent = NULL;
|
2011-12-14 15:29:38 -07:00
|
|
|
struct kobject *kobj;
|
2006-09-13 07:34:05 -06:00
|
|
|
struct class_interface *class_intf;
|
2008-05-30 11:45:12 -06:00
|
|
|
int error = -EINVAL;
|
2008-01-12 12:40:46 -07:00
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
dev = get_device(dev);
|
2008-05-30 11:45:12 -06:00
|
|
|
if (!dev)
|
|
|
|
goto done;
|
|
|
|
|
2008-12-16 13:23:36 -07:00
|
|
|
if (!dev->p) {
|
2009-05-11 15:16:57 -06:00
|
|
|
error = device_private_init(dev);
|
|
|
|
if (error)
|
|
|
|
goto done;
|
2008-12-16 13:23:36 -07:00
|
|
|
}
|
|
|
|
|
2009-01-25 07:17:37 -07:00
|
|
|
/*
|
|
|
|
* for statically allocated devices, which should all be converted
|
|
|
|
* some day, we need to initialize the name. We prevent reading back
|
|
|
|
* the name, and force the use of dev_name()
|
|
|
|
*/
|
|
|
|
if (dev->init_name) {
|
2009-06-02 16:39:55 -06:00
|
|
|
dev_set_name(dev, "%s", dev->init_name);
|
2009-01-25 07:17:37 -07:00
|
|
|
dev->init_name = NULL;
|
|
|
|
}
|
2008-05-30 11:45:12 -06:00
|
|
|
|
2011-12-14 15:29:38 -07:00
|
|
|
/* subsystems can specify simple device enumeration */
|
|
|
|
if (!dev_name(dev) && dev->bus && dev->bus->dev_name)
|
|
|
|
dev_set_name(dev, "%s%u", dev->bus->dev_name, dev->id);
|
|
|
|
|
2009-12-10 12:32:49 -07:00
|
|
|
if (!dev_name(dev)) {
|
|
|
|
error = -EINVAL;
|
2009-05-28 15:24:07 -06:00
|
|
|
goto name_error;
|
2009-12-10 12:32:49 -07:00
|
|
|
}
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2008-10-29 18:36:48 -06:00
|
|
|
pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
|
2006-08-07 23:19:37 -06:00
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
parent = get_device(dev->parent);
|
2011-12-14 15:29:38 -07:00
|
|
|
kobj = get_device_parent(dev, parent);
|
|
|
|
if (kobj)
|
|
|
|
dev->kobj.parent = kobj;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2008-02-19 04:20:41 -07:00
|
|
|
/* use parent numa_node */
|
|
|
|
if (parent)
|
|
|
|
set_dev_node(dev, dev_to_node(parent));
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/* first, register with generic layer. */
|
2009-04-18 16:05:45 -06:00
|
|
|
/* we require the name to be set before, and pass NULL */
|
|
|
|
error = kobject_add(&dev->kobj, dev->kobj.parent, NULL);
|
2006-10-23 17:37:58 -06:00
|
|
|
if (error)
|
2005-04-16 16:20:36 -06:00
|
|
|
goto Error;
|
2005-10-01 06:49:43 -06:00
|
|
|
|
2006-08-14 23:43:19 -06:00
|
|
|
/* notify platform of device entry */
|
|
|
|
if (platform_notify)
|
|
|
|
platform_notify(dev);
|
|
|
|
|
2013-08-23 18:07:26 -06:00
|
|
|
error = device_create_file(dev, &dev_attr_uevent);
|
2006-09-22 03:37:13 -06:00
|
|
|
if (error)
|
|
|
|
goto attrError;
|
2005-10-01 06:49:43 -06:00
|
|
|
|
2006-06-14 13:14:34 -06:00
|
|
|
if (MAJOR(dev->devt)) {
|
2013-08-23 18:07:26 -06:00
|
|
|
error = device_create_file(dev, &dev_attr_dev);
|
2007-06-13 12:45:17 -06:00
|
|
|
if (error)
|
2006-09-22 03:37:13 -06:00
|
|
|
goto ueventattrError;
|
2008-04-21 11:51:07 -06:00
|
|
|
|
|
|
|
error = device_create_sys_dev_entry(dev);
|
|
|
|
if (error)
|
|
|
|
goto devtattrError;
|
Driver Core: devtmpfs - kernel-maintained tmpfs-based /dev
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>
2009-04-30 07:23:42 -06:00
|
|
|
|
|
|
|
devtmpfs_create_node(dev);
|
2006-06-14 13:14:34 -06:00
|
|
|
}
|
|
|
|
|
2007-07-18 02:43:47 -06:00
|
|
|
error = device_add_class_symlinks(dev);
|
|
|
|
if (error)
|
|
|
|
goto SymlinkError;
|
2007-07-09 12:39:18 -06:00
|
|
|
error = device_add_attrs(dev);
|
|
|
|
if (error)
|
2006-06-28 17:19:58 -06:00
|
|
|
goto AttrsError;
|
2007-07-09 12:39:18 -06:00
|
|
|
error = bus_add_device(dev);
|
|
|
|
if (error)
|
2005-04-16 16:20:36 -06:00
|
|
|
goto BusError;
|
2008-08-07 11:06:12 -06:00
|
|
|
error = dpm_sysfs_add(dev);
|
2008-03-11 17:59:38 -06:00
|
|
|
if (error)
|
2008-08-07 11:06:12 -06:00
|
|
|
goto DPMError;
|
|
|
|
device_pm_add(dev);
|
2008-12-05 12:10:31 -07:00
|
|
|
|
|
|
|
/* Notify clients of device addition. This call must come
|
2012-01-11 08:12:06 -07:00
|
|
|
* after dpm_sysfs_add() and before kobject_uevent().
|
2008-12-05 12:10:31 -07:00
|
|
|
*/
|
|
|
|
if (dev->bus)
|
|
|
|
blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
|
|
|
|
BUS_NOTIFY_ADD_DEVICE, dev);
|
|
|
|
|
2007-03-29 03:12:11 -06:00
|
|
|
kobject_uevent(&dev->kobj, KOBJ_ADD);
|
2009-07-30 13:27:18 -06:00
|
|
|
bus_probe_device(dev);
|
2005-04-16 16:20:36 -06:00
|
|
|
if (parent)
|
2008-12-16 13:24:56 -07:00
|
|
|
klist_add_tail(&dev->p->knode_parent,
|
|
|
|
&parent->p->klist_children);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2006-06-22 18:17:32 -06:00
|
|
|
if (dev->class) {
|
2011-12-14 15:29:38 -07:00
|
|
|
mutex_lock(&dev->class->p->mutex);
|
2006-09-13 07:34:05 -06:00
|
|
|
/* tie the class to the device */
|
2008-08-25 11:50:19 -06:00
|
|
|
klist_add_tail(&dev->knode_class,
|
2010-11-15 15:13:18 -07:00
|
|
|
&dev->class->p->klist_devices);
|
2006-09-13 07:34:05 -06:00
|
|
|
|
|
|
|
/* notify any interfaces that the device is here */
|
2008-05-28 10:28:39 -06:00
|
|
|
list_for_each_entry(class_intf,
|
2011-12-14 15:29:38 -07:00
|
|
|
&dev->class->p->interfaces, node)
|
2006-09-13 07:34:05 -06:00
|
|
|
if (class_intf->add_dev)
|
|
|
|
class_intf->add_dev(dev, class_intf);
|
2011-12-14 15:29:38 -07:00
|
|
|
mutex_unlock(&dev->class->p->mutex);
|
2006-06-22 18:17:32 -06:00
|
|
|
}
|
2008-05-30 11:45:12 -06:00
|
|
|
done:
|
2005-04-16 16:20:36 -06:00
|
|
|
put_device(dev);
|
|
|
|
return error;
|
2008-08-07 11:06:12 -06:00
|
|
|
DPMError:
|
2008-03-11 17:59:38 -06:00
|
|
|
bus_remove_device(dev);
|
|
|
|
BusError:
|
2007-02-21 10:44:51 -07:00
|
|
|
device_remove_attrs(dev);
|
2006-06-28 17:19:58 -06:00
|
|
|
AttrsError:
|
2007-07-18 02:43:47 -06:00
|
|
|
device_remove_class_symlinks(dev);
|
|
|
|
SymlinkError:
|
2009-10-28 12:51:37 -06:00
|
|
|
if (MAJOR(dev->devt))
|
|
|
|
devtmpfs_delete_node(dev);
|
2008-04-21 11:51:07 -06:00
|
|
|
if (MAJOR(dev->devt))
|
|
|
|
device_remove_sys_dev_entry(dev);
|
|
|
|
devtattrError:
|
2007-06-13 12:45:17 -06:00
|
|
|
if (MAJOR(dev->devt))
|
2013-08-23 18:07:26 -06:00
|
|
|
device_remove_file(dev, &dev_attr_dev);
|
2006-09-22 03:37:13 -06:00
|
|
|
ueventattrError:
|
2013-08-23 18:07:26 -06:00
|
|
|
device_remove_file(dev, &dev_attr_uevent);
|
2006-06-14 13:14:34 -06:00
|
|
|
attrError:
|
2005-11-16 01:00:00 -07:00
|
|
|
kobject_uevent(&dev->kobj, KOBJ_REMOVE);
|
2005-04-16 16:20:36 -06:00
|
|
|
kobject_del(&dev->kobj);
|
|
|
|
Error:
|
2008-01-21 08:09:44 -07:00
|
|
|
cleanup_device_parent(dev);
|
2005-04-16 16:20:36 -06:00
|
|
|
if (parent)
|
|
|
|
put_device(parent);
|
2009-05-28 15:24:07 -06:00
|
|
|
name_error:
|
|
|
|
kfree(dev->p);
|
|
|
|
dev->p = NULL;
|
2008-05-30 11:45:12 -06:00
|
|
|
goto done;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2013-07-21 18:41:14 -06:00
|
|
|
EXPORT_SYMBOL_GPL(device_add);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* device_register - register a device with the system.
|
|
|
|
* @dev: pointer to the device structure
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-01-24 23:50:12 -07:00
|
|
|
* This happens in two clean steps - initialize the device
|
|
|
|
* and add it to the system. The two steps can be called
|
|
|
|
* separately, but this is the easiest and most common.
|
|
|
|
* I.e. you should only call the two helpers separately if
|
|
|
|
* have a clearly defined need to use and refcount the device
|
|
|
|
* before it is added to the hierarchy.
|
2008-09-03 10:26:40 -06:00
|
|
|
*
|
2012-01-17 09:39:00 -07:00
|
|
|
* For more information, see the kerneldoc for device_initialize()
|
|
|
|
* and device_add().
|
|
|
|
*
|
2008-09-03 10:26:40 -06:00
|
|
|
* NOTE: _Never_ directly free @dev after calling this function, even
|
|
|
|
* if it returned an error! Always use put_device() to give up the
|
|
|
|
* reference initialized in this function instead.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
|
|
|
int device_register(struct device *dev)
|
|
|
|
{
|
|
|
|
device_initialize(dev);
|
|
|
|
return device_add(dev);
|
|
|
|
}
|
2013-07-21 18:41:14 -06:00
|
|
|
EXPORT_SYMBOL_GPL(device_register);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* get_device - increment reference count for device.
|
|
|
|
* @dev: device.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-01-24 23:50:12 -07:00
|
|
|
* This simply forwards the call to kobject_get(), though
|
|
|
|
* we do take care to provide for the case that we get a NULL
|
|
|
|
* pointer passed in.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2008-01-24 23:50:12 -07:00
|
|
|
struct device *get_device(struct device *dev)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2012-07-03 10:49:36 -06:00
|
|
|
return dev ? kobj_to_dev(kobject_get(&dev->kobj)) : NULL;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2013-07-21 18:41:14 -06:00
|
|
|
EXPORT_SYMBOL_GPL(get_device);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* put_device - decrement reference count.
|
|
|
|
* @dev: device in question.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2008-01-24 23:50:12 -07:00
|
|
|
void put_device(struct device *dev)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2007-05-21 14:08:01 -06:00
|
|
|
/* might_sleep(); */
|
2005-04-16 16:20:36 -06:00
|
|
|
if (dev)
|
|
|
|
kobject_put(&dev->kobj);
|
|
|
|
}
|
2013-07-21 18:41:14 -06:00
|
|
|
EXPORT_SYMBOL_GPL(put_device);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* device_del - delete device from system.
|
|
|
|
* @dev: device.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-01-24 23:50:12 -07:00
|
|
|
* This is the first part of the device unregistration
|
|
|
|
* sequence. This removes the device from the lists we control
|
|
|
|
* from here, has it removed from the other driver model
|
|
|
|
* subsystems it was added to in device_add(), and removes it
|
|
|
|
* from the kobject hierarchy.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-01-24 23:50:12 -07:00
|
|
|
* NOTE: this should be called manually _iff_ device_add() was
|
|
|
|
* also called manually.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2008-01-24 23:50:12 -07:00
|
|
|
void device_del(struct device *dev)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2008-01-24 23:50:12 -07:00
|
|
|
struct device *parent = dev->parent;
|
2006-09-13 07:34:05 -06:00
|
|
|
struct class_interface *class_intf;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2008-12-05 12:10:31 -07:00
|
|
|
/* Notify clients of device removal. This call must come
|
|
|
|
* before dpm_sysfs_remove().
|
|
|
|
*/
|
|
|
|
if (dev->bus)
|
|
|
|
blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
|
|
|
|
BUS_NOTIFY_DEL_DEVICE, dev);
|
2008-08-07 11:06:12 -06:00
|
|
|
dpm_sysfs_remove(dev);
|
2005-04-16 16:20:36 -06:00
|
|
|
if (parent)
|
2008-12-16 13:24:56 -07:00
|
|
|
klist_del(&dev->p->knode_parent);
|
2008-04-21 11:51:07 -06:00
|
|
|
if (MAJOR(dev->devt)) {
|
Driver Core: devtmpfs - kernel-maintained tmpfs-based /dev
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>
2009-04-30 07:23:42 -06:00
|
|
|
devtmpfs_delete_node(dev);
|
2008-04-21 11:51:07 -06:00
|
|
|
device_remove_sys_dev_entry(dev);
|
2013-08-23 18:07:26 -06:00
|
|
|
device_remove_file(dev, &dev_attr_dev);
|
2008-04-21 11:51:07 -06:00
|
|
|
}
|
2006-06-15 07:31:56 -06:00
|
|
|
if (dev->class) {
|
2007-11-21 09:29:15 -07:00
|
|
|
device_remove_class_symlinks(dev);
|
2006-09-14 03:23:28 -06:00
|
|
|
|
2011-12-14 15:29:38 -07:00
|
|
|
mutex_lock(&dev->class->p->mutex);
|
2006-09-13 07:34:05 -06:00
|
|
|
/* notify any interfaces that the device is now gone */
|
2008-05-28 10:28:39 -06:00
|
|
|
list_for_each_entry(class_intf,
|
2011-12-14 15:29:38 -07:00
|
|
|
&dev->class->p->interfaces, node)
|
2006-09-13 07:34:05 -06:00
|
|
|
if (class_intf->remove_dev)
|
|
|
|
class_intf->remove_dev(dev, class_intf);
|
|
|
|
/* remove the device from the class list */
|
2008-08-25 11:50:19 -06:00
|
|
|
klist_del(&dev->knode_class);
|
2011-12-14 15:29:38 -07:00
|
|
|
mutex_unlock(&dev->class->p->mutex);
|
2006-06-15 07:31:56 -06:00
|
|
|
}
|
2013-08-23 18:07:26 -06:00
|
|
|
device_remove_file(dev, &dev_attr_uevent);
|
2006-06-28 17:19:58 -06:00
|
|
|
device_remove_attrs(dev);
|
2006-11-08 20:46:14 -07:00
|
|
|
bus_remove_device(dev);
|
driver core / PM: move the calling to device_pm_remove behind the calling to bus_remove_device
We hit an hang issue when removing a mmc device on Medfield Android phone by sysfs interface.
device_pm_remove will call pm_runtime_remove which would disable
runtime PM of the device. After that pm_runtime_get* or
pm_runtime_put* will be ignored. So if we disable the runtime PM
before device really be removed, drivers' _remove callback may
access HW even pm_runtime_get* fails. That is bad.
Consider below call sequence when removing a device:
device_del => device_pm_remove
=> class_intf->remove_dev(dev, class_intf) => pm_runtime_get_sync/put_sync
=> bus_remove_device => device_release_driver => pm_runtime_get_sync/put_sync
remove_dev might call pm_runtime_get_sync/put_sync.
Then, generic device_release_driver also calls pm_runtime_get_sync/put_sync.
Since device_del => device_pm_remove firstly, later _get_sync wouldn't really wake up the device.
I git log -p to find the patch which moves the calling to device_pm_remove ahead.
It's below patch:
commit 775b64d2b6ca37697de925f70799c710aab5849a
Author: Rafael J. Wysocki <rjw@sisk.pl>
Date: Sat Jan 12 20:40:46 2008 +0100
PM: Acquire device locks on suspend
This patch reorganizes the way suspend and resume notifications are
sent to drivers. The major changes are that now the PM core acquires
every device semaphore before calling the methods, and calls to
device_add() during suspends will fail, while calls to device_del()
during suspends will block.
It also provides a way to safely remove a suspended device with the
help of the PM core, by using the device_pm_schedule_removal() callback
introduced specifically for this purpose, and updates two drivers (msr
and cpuid) that need to use it.
As device_pm_schedule_removal is deleted by another patch, we need also revert other parts of the patch,
i.e. move the calling of device_pm_remove after the calling to bus_remove_device.
Signed-off-by: LongX Zhang <longx.zhang@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-10-24 16:21:28 -06:00
|
|
|
device_pm_remove(dev);
|
2012-03-05 08:47:41 -07:00
|
|
|
driver_deferred_probe_del(dev);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/* Notify the platform of the removal, in case they
|
|
|
|
* need to do anything...
|
|
|
|
*/
|
|
|
|
if (platform_notify_remove)
|
|
|
|
platform_notify_remove(dev);
|
2005-11-16 01:00:00 -07:00
|
|
|
kobject_uevent(&dev->kobj, KOBJ_REMOVE);
|
2007-11-21 09:29:15 -07:00
|
|
|
cleanup_device_parent(dev);
|
2005-04-16 16:20:36 -06:00
|
|
|
kobject_del(&dev->kobj);
|
2007-11-21 09:29:15 -07:00
|
|
|
put_device(parent);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2013-07-21 18:41:14 -06:00
|
|
|
EXPORT_SYMBOL_GPL(device_del);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* device_unregister - unregister device from system.
|
|
|
|
* @dev: device going away.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-01-24 23:50:12 -07:00
|
|
|
* We do this in two parts, like we do device_register(). First,
|
|
|
|
* we remove it from all the subsystems with device_del(), then
|
|
|
|
* we decrement the reference count via put_device(). If that
|
|
|
|
* is the final reference count, the device will be cleaned up
|
|
|
|
* via device_release() above. Otherwise, the structure will
|
|
|
|
* stick around until the final reference to the device is dropped.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2008-01-24 23:50:12 -07:00
|
|
|
void device_unregister(struct device *dev)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2008-10-29 18:36:48 -06:00
|
|
|
pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
|
2005-04-16 16:20:36 -06:00
|
|
|
device_del(dev);
|
|
|
|
put_device(dev);
|
|
|
|
}
|
2013-07-21 18:41:14 -06:00
|
|
|
EXPORT_SYMBOL_GPL(device_unregister);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2008-01-24 23:50:12 -07:00
|
|
|
static struct device *next_device(struct klist_iter *i)
|
2005-03-24 20:08:30 -07:00
|
|
|
{
|
2008-01-24 23:50:12 -07:00
|
|
|
struct klist_node *n = klist_next(i);
|
2008-12-16 13:24:56 -07:00
|
|
|
struct device *dev = NULL;
|
|
|
|
struct device_private *p;
|
|
|
|
|
|
|
|
if (n) {
|
|
|
|
p = to_device_private_parent(n);
|
|
|
|
dev = p->device;
|
|
|
|
}
|
|
|
|
return dev;
|
2005-03-24 20:08:30 -07:00
|
|
|
}
|
|
|
|
|
2009-04-30 07:23:42 -06:00
|
|
|
/**
|
2009-09-18 15:01:12 -06:00
|
|
|
* device_get_devnode - path of device node file
|
2009-04-30 07:23:42 -06:00
|
|
|
* @dev: device
|
2009-09-18 15:01:12 -06:00
|
|
|
* @mode: returned file access mode
|
2013-04-06 10:56:00 -06:00
|
|
|
* @uid: returned file owner
|
|
|
|
* @gid: returned file group
|
2009-04-30 07:23:42 -06:00
|
|
|
* @tmp: possibly allocated string
|
|
|
|
*
|
|
|
|
* Return the relative path of a possible device node.
|
|
|
|
* Non-default names may need to allocate a memory to compose
|
|
|
|
* a name. This memory is returned in tmp and needs to be
|
|
|
|
* freed by the caller.
|
|
|
|
*/
|
2009-09-18 15:01:12 -06:00
|
|
|
const char *device_get_devnode(struct device *dev,
|
2013-04-11 12:43:29 -06:00
|
|
|
umode_t *mode, kuid_t *uid, kgid_t *gid,
|
2013-04-06 10:56:00 -06:00
|
|
|
const char **tmp)
|
2009-04-30 07:23:42 -06:00
|
|
|
{
|
|
|
|
char *s;
|
|
|
|
|
|
|
|
*tmp = NULL;
|
|
|
|
|
|
|
|
/* the device type may provide a specific name */
|
2009-09-18 15:01:12 -06:00
|
|
|
if (dev->type && dev->type->devnode)
|
2013-04-06 10:56:00 -06:00
|
|
|
*tmp = dev->type->devnode(dev, mode, uid, gid);
|
2009-04-30 07:23:42 -06:00
|
|
|
if (*tmp)
|
|
|
|
return *tmp;
|
|
|
|
|
|
|
|
/* the class may provide a specific name */
|
2009-09-18 15:01:12 -06:00
|
|
|
if (dev->class && dev->class->devnode)
|
|
|
|
*tmp = dev->class->devnode(dev, mode);
|
2009-04-30 07:23:42 -06:00
|
|
|
if (*tmp)
|
|
|
|
return *tmp;
|
|
|
|
|
|
|
|
/* return name without allocation, tmp == NULL */
|
|
|
|
if (strchr(dev_name(dev), '!') == NULL)
|
|
|
|
return dev_name(dev);
|
|
|
|
|
|
|
|
/* replace '!' in the name with '/' */
|
|
|
|
*tmp = kstrdup(dev_name(dev), GFP_KERNEL);
|
|
|
|
if (!*tmp)
|
|
|
|
return NULL;
|
|
|
|
while ((s = strchr(*tmp, '!')))
|
|
|
|
s[0] = '/';
|
|
|
|
return *tmp;
|
|
|
|
}
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* device_for_each_child - device child iterator.
|
|
|
|
* @parent: parent struct device.
|
|
|
|
* @fn: function to be called for each device.
|
2013-06-01 18:17:34 -06:00
|
|
|
* @data: data for the callback.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-01-24 23:50:12 -07:00
|
|
|
* Iterate over @parent's child devices, and call @fn for each,
|
|
|
|
* passing it @data.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-01-24 23:50:12 -07:00
|
|
|
* We check the return of @fn each time. If it returns anything
|
|
|
|
* other than 0, we break out and return that value.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2008-01-24 23:50:12 -07:00
|
|
|
int device_for_each_child(struct device *parent, void *data,
|
|
|
|
int (*fn)(struct device *dev, void *data))
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2005-03-24 20:08:30 -07:00
|
|
|
struct klist_iter i;
|
2008-01-24 23:50:12 -07:00
|
|
|
struct device *child;
|
2005-04-16 16:20:36 -06:00
|
|
|
int error = 0;
|
|
|
|
|
2009-04-15 17:00:12 -06:00
|
|
|
if (!parent->p)
|
|
|
|
return 0;
|
|
|
|
|
2008-12-16 13:24:56 -07:00
|
|
|
klist_iter_init(&parent->p->klist_children, &i);
|
2005-03-24 20:08:30 -07:00
|
|
|
while ((child = next_device(&i)) && !error)
|
|
|
|
error = fn(child, data);
|
|
|
|
klist_iter_exit(&i);
|
2005-04-16 16:20:36 -06:00
|
|
|
return error;
|
|
|
|
}
|
2013-07-21 18:41:14 -06:00
|
|
|
EXPORT_SYMBOL_GPL(device_for_each_child);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2006-11-16 07:42:07 -07:00
|
|
|
/**
|
|
|
|
* device_find_child - device iterator for locating a particular device.
|
|
|
|
* @parent: parent struct device
|
|
|
|
* @match: Callback function to check device
|
2013-06-01 18:17:34 -06:00
|
|
|
* @data: Data to pass to match function
|
2006-11-16 07:42:07 -07:00
|
|
|
*
|
|
|
|
* This is similar to the device_for_each_child() function above, but it
|
|
|
|
* returns a reference to a device that is 'found' for later use, as
|
|
|
|
* determined by the @match callback.
|
|
|
|
*
|
|
|
|
* The callback should return 0 if the device doesn't match and non-zero
|
|
|
|
* if it does. If the callback returns non-zero and a reference to the
|
|
|
|
* current device can be obtained, this function will return to the caller
|
|
|
|
* and not iterate over any more devices.
|
2013-04-15 03:18:11 -06:00
|
|
|
*
|
|
|
|
* NOTE: you will need to drop the reference with put_device() after use.
|
2006-11-16 07:42:07 -07:00
|
|
|
*/
|
2008-01-24 23:50:12 -07:00
|
|
|
struct device *device_find_child(struct device *parent, void *data,
|
|
|
|
int (*match)(struct device *dev, void *data))
|
2006-11-16 07:42:07 -07:00
|
|
|
{
|
|
|
|
struct klist_iter i;
|
|
|
|
struct device *child;
|
|
|
|
|
|
|
|
if (!parent)
|
|
|
|
return NULL;
|
|
|
|
|
2008-12-16 13:24:56 -07:00
|
|
|
klist_iter_init(&parent->p->klist_children, &i);
|
2006-11-16 07:42:07 -07:00
|
|
|
while ((child = next_device(&i)))
|
|
|
|
if (match(child, data) && get_device(child))
|
|
|
|
break;
|
|
|
|
klist_iter_exit(&i);
|
|
|
|
return child;
|
|
|
|
}
|
2013-07-21 18:41:14 -06:00
|
|
|
EXPORT_SYMBOL_GPL(device_find_child);
|
2006-11-16 07:42:07 -07:00
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
int __init devices_init(void)
|
|
|
|
{
|
2007-11-01 09:29:06 -06:00
|
|
|
devices_kset = kset_create_and_add("devices", &device_uevent_ops, NULL);
|
|
|
|
if (!devices_kset)
|
|
|
|
return -ENOMEM;
|
2008-04-21 11:51:07 -06:00
|
|
|
dev_kobj = kobject_create_and_add("dev", NULL);
|
|
|
|
if (!dev_kobj)
|
|
|
|
goto dev_kobj_err;
|
|
|
|
sysfs_dev_block_kobj = kobject_create_and_add("block", dev_kobj);
|
|
|
|
if (!sysfs_dev_block_kobj)
|
|
|
|
goto block_kobj_err;
|
|
|
|
sysfs_dev_char_kobj = kobject_create_and_add("char", dev_kobj);
|
|
|
|
if (!sysfs_dev_char_kobj)
|
|
|
|
goto char_kobj_err;
|
|
|
|
|
2007-11-01 09:29:06 -06:00
|
|
|
return 0;
|
2008-04-21 11:51:07 -06:00
|
|
|
|
|
|
|
char_kobj_err:
|
|
|
|
kobject_put(sysfs_dev_block_kobj);
|
|
|
|
block_kobj_err:
|
|
|
|
kobject_put(dev_kobj);
|
|
|
|
dev_kobj_err:
|
|
|
|
kset_unregister(devices_kset);
|
|
|
|
return -ENOMEM;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
Driver core: Add offline/online device operations
In some cases, graceful hot-removal of devices is not possible,
although in principle the devices in question support hotplug.
For example, that may happen for the last CPU in the system or
for memory modules holding kernel memory.
In those cases it is nice to be able to check if the given device
can be gracefully hot-removed before triggering a removal procedure
that cannot be aborted or reversed. Unfortunately, however, the
kernel currently doesn't provide any support for that.
To address that deficiency, introduce support for offline and
online operations that can be performed on devices, respectively,
before a hot-removal and in case when it is necessary (or convenient)
to put a device back online after a successful offline (that has not
been followed by removal). The idea is that the offline will fail
whenever the given device cannot be gracefully removed from the
system and it will not be allowed to use the device after a
successful offline (until a subsequent online) in analogy with the
existing CPU offline/online mechanism.
For now, the offline and online operations are introduced at the
bus type level, as that should be sufficient for the most urgent use
cases (CPUs and memory modules). In the future, however, the
approach may be extended to cover some more complicated device
offline/online scenarios involving device drivers etc.
The lock_device_hotplug() and unlock_device_hotplug() functions are
introduced because subsequent patches need to put larger pieces of
code under device_hotplug_lock to prevent race conditions between
device offline and removal from happening.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Toshi Kani <toshi.kani@hp.com>
2013-05-02 14:15:29 -06:00
|
|
|
static int device_check_offline(struct device *dev, void *not_used)
|
|
|
|
{
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
ret = device_for_each_child(dev, NULL, device_check_offline);
|
|
|
|
if (ret)
|
|
|
|
return ret;
|
|
|
|
|
|
|
|
return device_supports_offline(dev) && !dev->offline ? -EBUSY : 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* device_offline - Prepare the device for hot-removal.
|
|
|
|
* @dev: Device to be put offline.
|
|
|
|
*
|
|
|
|
* Execute the device bus type's .offline() callback, if present, to prepare
|
|
|
|
* the device for a subsequent hot-removal. If that succeeds, the device must
|
|
|
|
* not be used until either it is removed or its bus type's .online() callback
|
|
|
|
* is executed.
|
|
|
|
*
|
|
|
|
* Call under device_hotplug_lock.
|
|
|
|
*/
|
|
|
|
int device_offline(struct device *dev)
|
|
|
|
{
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
if (dev->offline_disabled)
|
|
|
|
return -EPERM;
|
|
|
|
|
|
|
|
ret = device_for_each_child(dev, NULL, device_check_offline);
|
|
|
|
if (ret)
|
|
|
|
return ret;
|
|
|
|
|
|
|
|
device_lock(dev);
|
|
|
|
if (device_supports_offline(dev)) {
|
|
|
|
if (dev->offline) {
|
|
|
|
ret = 1;
|
|
|
|
} else {
|
|
|
|
ret = dev->bus->offline(dev);
|
|
|
|
if (!ret) {
|
|
|
|
kobject_uevent(&dev->kobj, KOBJ_OFFLINE);
|
|
|
|
dev->offline = true;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
device_unlock(dev);
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* device_online - Put the device back online after successful device_offline().
|
|
|
|
* @dev: Device to be put back online.
|
|
|
|
*
|
|
|
|
* If device_offline() has been successfully executed for @dev, but the device
|
|
|
|
* has not been removed subsequently, execute its bus type's .online() callback
|
|
|
|
* to indicate that the device can be used again.
|
|
|
|
*
|
|
|
|
* Call under device_hotplug_lock.
|
|
|
|
*/
|
|
|
|
int device_online(struct device *dev)
|
|
|
|
{
|
|
|
|
int ret = 0;
|
|
|
|
|
|
|
|
device_lock(dev);
|
|
|
|
if (device_supports_offline(dev)) {
|
|
|
|
if (dev->offline) {
|
|
|
|
ret = dev->bus->online(dev);
|
|
|
|
if (!ret) {
|
|
|
|
kobject_uevent(&dev->kobj, KOBJ_ONLINE);
|
|
|
|
dev->offline = false;
|
|
|
|
}
|
|
|
|
} else {
|
|
|
|
ret = 1;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
device_unlock(dev);
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
2011-04-18 15:16:52 -06:00
|
|
|
struct root_device {
|
2008-12-15 05:58:26 -07:00
|
|
|
struct device dev;
|
|
|
|
struct module *owner;
|
|
|
|
};
|
|
|
|
|
2012-11-18 22:27:55 -07:00
|
|
|
static inline struct root_device *to_root_device(struct device *d)
|
2011-01-07 07:17:47 -07:00
|
|
|
{
|
|
|
|
return container_of(d, struct root_device, dev);
|
|
|
|
}
|
2008-12-15 05:58:26 -07:00
|
|
|
|
|
|
|
static void root_device_release(struct device *dev)
|
|
|
|
{
|
|
|
|
kfree(to_root_device(dev));
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* __root_device_register - allocate and register a root device
|
|
|
|
* @name: root device name
|
|
|
|
* @owner: owner module of the root device, usually THIS_MODULE
|
|
|
|
*
|
|
|
|
* This function allocates a root device and registers it
|
|
|
|
* using device_register(). In order to free the returned
|
|
|
|
* device, use root_device_unregister().
|
|
|
|
*
|
|
|
|
* Root devices are dummy devices which allow other devices
|
|
|
|
* to be grouped under /sys/devices. Use this function to
|
|
|
|
* allocate a root device and then use it as the parent of
|
|
|
|
* any device which should appear under /sys/devices/{name}
|
|
|
|
*
|
|
|
|
* The /sys/devices/{name} directory will also contain a
|
|
|
|
* 'module' symlink which points to the @owner directory
|
|
|
|
* in sysfs.
|
|
|
|
*
|
2010-03-11 09:11:45 -07:00
|
|
|
* Returns &struct device pointer on success, or ERR_PTR() on error.
|
|
|
|
*
|
2008-12-15 05:58:26 -07:00
|
|
|
* Note: You probably want to use root_device_register().
|
|
|
|
*/
|
|
|
|
struct device *__root_device_register(const char *name, struct module *owner)
|
|
|
|
{
|
|
|
|
struct root_device *root;
|
|
|
|
int err = -ENOMEM;
|
|
|
|
|
|
|
|
root = kzalloc(sizeof(struct root_device), GFP_KERNEL);
|
|
|
|
if (!root)
|
|
|
|
return ERR_PTR(err);
|
|
|
|
|
2009-06-02 16:39:55 -06:00
|
|
|
err = dev_set_name(&root->dev, "%s", name);
|
2008-12-15 05:58:26 -07:00
|
|
|
if (err) {
|
|
|
|
kfree(root);
|
|
|
|
return ERR_PTR(err);
|
|
|
|
}
|
|
|
|
|
|
|
|
root->dev.release = root_device_release;
|
|
|
|
|
|
|
|
err = device_register(&root->dev);
|
|
|
|
if (err) {
|
|
|
|
put_device(&root->dev);
|
|
|
|
return ERR_PTR(err);
|
|
|
|
}
|
|
|
|
|
2010-05-17 08:57:58 -06:00
|
|
|
#ifdef CONFIG_MODULES /* gotta find a "cleaner" way to do this */
|
2008-12-15 05:58:26 -07:00
|
|
|
if (owner) {
|
|
|
|
struct module_kobject *mk = &owner->mkobj;
|
|
|
|
|
|
|
|
err = sysfs_create_link(&root->dev.kobj, &mk->kobj, "module");
|
|
|
|
if (err) {
|
|
|
|
device_unregister(&root->dev);
|
|
|
|
return ERR_PTR(err);
|
|
|
|
}
|
|
|
|
root->owner = owner;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
return &root->dev;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(__root_device_register);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* root_device_unregister - unregister and free a root device
|
2009-01-20 17:29:13 -07:00
|
|
|
* @dev: device going away
|
2008-12-15 05:58:26 -07:00
|
|
|
*
|
|
|
|
* This function unregisters and cleans up a device that was created by
|
|
|
|
* root_device_register().
|
|
|
|
*/
|
|
|
|
void root_device_unregister(struct device *dev)
|
|
|
|
{
|
|
|
|
struct root_device *root = to_root_device(dev);
|
|
|
|
|
|
|
|
if (root->owner)
|
|
|
|
sysfs_remove_link(&root->dev.kobj, "module");
|
|
|
|
|
|
|
|
device_unregister(dev);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(root_device_unregister);
|
|
|
|
|
2006-06-14 13:14:34 -06:00
|
|
|
|
|
|
|
static void device_create_release(struct device *dev)
|
|
|
|
{
|
2008-10-29 18:36:48 -06:00
|
|
|
pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
|
2006-06-14 13:14:34 -06:00
|
|
|
kfree(dev);
|
|
|
|
}
|
|
|
|
|
2013-07-14 17:05:57 -06:00
|
|
|
static struct device *
|
|
|
|
device_create_groups_vargs(struct class *class, struct device *parent,
|
|
|
|
dev_t devt, void *drvdata,
|
|
|
|
const struct attribute_group **groups,
|
|
|
|
const char *fmt, va_list args)
|
2006-06-14 13:14:34 -06:00
|
|
|
{
|
|
|
|
struct device *dev = NULL;
|
|
|
|
int retval = -ENODEV;
|
|
|
|
|
|
|
|
if (class == NULL || IS_ERR(class))
|
|
|
|
goto error;
|
|
|
|
|
|
|
|
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
|
|
|
|
if (!dev) {
|
|
|
|
retval = -ENOMEM;
|
|
|
|
goto error;
|
|
|
|
}
|
|
|
|
|
2013-11-21 12:15:48 -07:00
|
|
|
device_initialize(dev);
|
2006-06-14 13:14:34 -06:00
|
|
|
dev->devt = devt;
|
|
|
|
dev->class = class;
|
|
|
|
dev->parent = parent;
|
2013-07-14 17:05:57 -06:00
|
|
|
dev->groups = groups;
|
2006-06-14 13:14:34 -06:00
|
|
|
dev->release = device_create_release;
|
2008-05-15 14:44:08 -06:00
|
|
|
dev_set_drvdata(dev, drvdata);
|
2006-06-14 13:14:34 -06:00
|
|
|
|
2009-01-25 07:17:37 -07:00
|
|
|
retval = kobject_set_name_vargs(&dev->kobj, fmt, args);
|
|
|
|
if (retval)
|
|
|
|
goto error;
|
|
|
|
|
2013-11-21 12:15:48 -07:00
|
|
|
retval = device_add(dev);
|
2006-06-14 13:14:34 -06:00
|
|
|
if (retval)
|
|
|
|
goto error;
|
|
|
|
|
|
|
|
return dev;
|
|
|
|
|
|
|
|
error:
|
2008-09-03 10:26:41 -06:00
|
|
|
put_device(dev);
|
2006-06-14 13:14:34 -06:00
|
|
|
return ERR_PTR(retval);
|
|
|
|
}
|
2013-07-14 17:05:57 -06:00
|
|
|
|
|
|
|
/**
|
|
|
|
* device_create_vargs - creates a device and registers it with sysfs
|
|
|
|
* @class: pointer to the struct class that this device should be registered to
|
|
|
|
* @parent: pointer to the parent struct device of this new device, if any
|
|
|
|
* @devt: the dev_t for the char device to be added
|
|
|
|
* @drvdata: the data to be added to the device for callbacks
|
|
|
|
* @fmt: string for the device's name
|
|
|
|
* @args: va_list for the device's name
|
|
|
|
*
|
|
|
|
* This function can be used by char device classes. A struct device
|
|
|
|
* will be created in sysfs, registered to the specified class.
|
|
|
|
*
|
|
|
|
* A "dev" file will be created, showing the dev_t for the device, if
|
|
|
|
* the dev_t is not 0,0.
|
|
|
|
* If a pointer to a parent struct device is passed in, the newly created
|
|
|
|
* struct device will be a child of that device in sysfs.
|
|
|
|
* The pointer to the struct device will be returned from the call.
|
|
|
|
* Any further sysfs files that might be required can be created using this
|
|
|
|
* pointer.
|
|
|
|
*
|
|
|
|
* Returns &struct device pointer on success, or ERR_PTR() on error.
|
|
|
|
*
|
|
|
|
* Note: the struct class passed to this function must have previously
|
|
|
|
* been created with a call to class_create().
|
|
|
|
*/
|
|
|
|
struct device *device_create_vargs(struct class *class, struct device *parent,
|
|
|
|
dev_t devt, void *drvdata, const char *fmt,
|
|
|
|
va_list args)
|
|
|
|
{
|
|
|
|
return device_create_groups_vargs(class, parent, devt, drvdata, NULL,
|
|
|
|
fmt, args);
|
|
|
|
}
|
2008-05-15 14:44:08 -06:00
|
|
|
EXPORT_SYMBOL_GPL(device_create_vargs);
|
|
|
|
|
|
|
|
/**
|
2008-07-21 21:03:34 -06:00
|
|
|
* device_create - creates a device and registers it with sysfs
|
2008-05-15 14:44:08 -06:00
|
|
|
* @class: pointer to the struct class that this device should be registered to
|
|
|
|
* @parent: pointer to the parent struct device of this new device, if any
|
|
|
|
* @devt: the dev_t for the char device to be added
|
|
|
|
* @drvdata: the data to be added to the device for callbacks
|
|
|
|
* @fmt: string for the device's name
|
|
|
|
*
|
|
|
|
* This function can be used by char device classes. A struct device
|
|
|
|
* will be created in sysfs, registered to the specified class.
|
|
|
|
*
|
|
|
|
* A "dev" file will be created, showing the dev_t for the device, if
|
|
|
|
* the dev_t is not 0,0.
|
|
|
|
* If a pointer to a parent struct device is passed in, the newly created
|
|
|
|
* struct device will be a child of that device in sysfs.
|
|
|
|
* The pointer to the struct device will be returned from the call.
|
|
|
|
* Any further sysfs files that might be required can be created using this
|
|
|
|
* pointer.
|
|
|
|
*
|
2010-03-11 09:11:45 -07:00
|
|
|
* Returns &struct device pointer on success, or ERR_PTR() on error.
|
|
|
|
*
|
2008-05-15 14:44:08 -06:00
|
|
|
* Note: the struct class passed to this function must have previously
|
|
|
|
* been created with a call to class_create().
|
|
|
|
*/
|
2008-07-21 21:03:34 -06:00
|
|
|
struct device *device_create(struct class *class, struct device *parent,
|
|
|
|
dev_t devt, void *drvdata, const char *fmt, ...)
|
2008-05-15 14:44:08 -06:00
|
|
|
{
|
|
|
|
va_list vargs;
|
|
|
|
struct device *dev;
|
|
|
|
|
|
|
|
va_start(vargs, fmt);
|
|
|
|
dev = device_create_vargs(class, parent, devt, drvdata, fmt, vargs);
|
|
|
|
va_end(vargs);
|
|
|
|
return dev;
|
|
|
|
}
|
2008-07-21 21:03:34 -06:00
|
|
|
EXPORT_SYMBOL_GPL(device_create);
|
2008-05-15 14:44:08 -06:00
|
|
|
|
2013-07-14 17:05:57 -06:00
|
|
|
/**
|
|
|
|
* device_create_with_groups - creates a device and registers it with sysfs
|
|
|
|
* @class: pointer to the struct class that this device should be registered to
|
|
|
|
* @parent: pointer to the parent struct device of this new device, if any
|
|
|
|
* @devt: the dev_t for the char device to be added
|
|
|
|
* @drvdata: the data to be added to the device for callbacks
|
|
|
|
* @groups: NULL-terminated list of attribute groups to be created
|
|
|
|
* @fmt: string for the device's name
|
|
|
|
*
|
|
|
|
* This function can be used by char device classes. A struct device
|
|
|
|
* will be created in sysfs, registered to the specified class.
|
|
|
|
* Additional attributes specified in the groups parameter will also
|
|
|
|
* be created automatically.
|
|
|
|
*
|
|
|
|
* A "dev" file will be created, showing the dev_t for the device, if
|
|
|
|
* the dev_t is not 0,0.
|
|
|
|
* If a pointer to a parent struct device is passed in, the newly created
|
|
|
|
* struct device will be a child of that device in sysfs.
|
|
|
|
* The pointer to the struct device will be returned from the call.
|
|
|
|
* Any further sysfs files that might be required can be created using this
|
|
|
|
* pointer.
|
|
|
|
*
|
|
|
|
* Returns &struct device pointer on success, or ERR_PTR() on error.
|
|
|
|
*
|
|
|
|
* Note: the struct class passed to this function must have previously
|
|
|
|
* been created with a call to class_create().
|
|
|
|
*/
|
|
|
|
struct device *device_create_with_groups(struct class *class,
|
|
|
|
struct device *parent, dev_t devt,
|
|
|
|
void *drvdata,
|
|
|
|
const struct attribute_group **groups,
|
|
|
|
const char *fmt, ...)
|
|
|
|
{
|
|
|
|
va_list vargs;
|
|
|
|
struct device *dev;
|
|
|
|
|
|
|
|
va_start(vargs, fmt);
|
|
|
|
dev = device_create_groups_vargs(class, parent, devt, drvdata, groups,
|
|
|
|
fmt, vargs);
|
|
|
|
va_end(vargs);
|
|
|
|
return dev;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(device_create_with_groups);
|
|
|
|
|
2013-02-01 12:40:17 -07:00
|
|
|
static int __match_devt(struct device *dev, const void *data)
|
2006-06-14 13:14:34 -06:00
|
|
|
{
|
2013-02-01 12:40:17 -07:00
|
|
|
const dev_t *devt = data;
|
2006-06-14 13:14:34 -06:00
|
|
|
|
2008-01-28 01:56:11 -07:00
|
|
|
return dev->devt == *devt;
|
2008-01-12 12:40:46 -07:00
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* device_destroy - removes a device that was created with device_create()
|
|
|
|
* @class: pointer to the struct class that this device was registered with
|
|
|
|
* @devt: the dev_t of the device that was previously registered
|
|
|
|
*
|
|
|
|
* This call unregisters and cleans up a device that was created with a
|
|
|
|
* call to device_create().
|
|
|
|
*/
|
|
|
|
void device_destroy(struct class *class, dev_t devt)
|
|
|
|
{
|
|
|
|
struct device *dev;
|
2006-06-14 13:14:34 -06:00
|
|
|
|
2008-05-22 15:21:08 -06:00
|
|
|
dev = class_find_device(class, NULL, &devt, __match_devt);
|
2008-01-28 01:56:11 -07:00
|
|
|
if (dev) {
|
|
|
|
put_device(dev);
|
2006-06-14 13:14:34 -06:00
|
|
|
device_unregister(dev);
|
2008-01-28 01:56:11 -07:00
|
|
|
}
|
2006-06-14 13:14:34 -06:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(device_destroy);
|
2006-07-03 15:31:12 -06:00
|
|
|
|
|
|
|
/**
|
|
|
|
* device_rename - renames a device
|
|
|
|
* @dev: the pointer to the struct device to be renamed
|
|
|
|
* @new_name: the new name of the device
|
2008-05-08 15:41:00 -06:00
|
|
|
*
|
|
|
|
* It is the responsibility of the caller to provide mutual
|
|
|
|
* exclusion between two different calls of device_rename
|
|
|
|
* on the same device to ensure that new_name is valid and
|
|
|
|
* won't conflict with other devices.
|
2010-11-24 15:44:07 -07:00
|
|
|
*
|
2010-12-13 13:08:52 -07:00
|
|
|
* Note: Don't call this function. Currently, the networking layer calls this
|
|
|
|
* function, but that will change. The following text from Kay Sievers offers
|
|
|
|
* some insight:
|
|
|
|
*
|
|
|
|
* Renaming devices is racy at many levels, symlinks and other stuff are not
|
|
|
|
* replaced atomically, and you get a "move" uevent, but it's not easy to
|
|
|
|
* connect the event to the old and new device. Device nodes are not renamed at
|
|
|
|
* all, there isn't even support for that in the kernel now.
|
|
|
|
*
|
|
|
|
* In the meantime, during renaming, your target name might be taken by another
|
|
|
|
* driver, creating conflicts. Or the old name is taken directly after you
|
|
|
|
* renamed it -- then you get events for the same DEVPATH, before you even see
|
|
|
|
* the "move" event. It's just a mess, and nothing new should ever rely on
|
|
|
|
* kernel device renaming. Besides that, it's not even implemented now for
|
|
|
|
* other things than (driver-core wise very simple) network devices.
|
|
|
|
*
|
|
|
|
* We are currently about to change network renaming in udev to completely
|
|
|
|
* disallow renaming of devices in the same namespace as the kernel uses,
|
|
|
|
* because we can't solve the problems properly, that arise with swapping names
|
|
|
|
* of multiple interfaces without races. Means, renaming of eth[0-9]* will only
|
|
|
|
* be allowed to some other name than eth[0-9]*, for the aforementioned
|
|
|
|
* reasons.
|
|
|
|
*
|
|
|
|
* Make up a "real" name in the driver before you register anything, or add
|
|
|
|
* some other attributes for userspace to find the device, or use udev to add
|
|
|
|
* symlinks -- but never rename kernel devices later, it's a complete mess. We
|
|
|
|
* don't even want to get into that and try to implement the missing pieces in
|
|
|
|
* the core. We really have other pieces to fix in the driver core mess. :)
|
2006-07-03 15:31:12 -06:00
|
|
|
*/
|
2010-08-05 09:38:18 -06:00
|
|
|
int device_rename(struct device *dev, const char *new_name)
|
2006-07-03 15:31:12 -06:00
|
|
|
{
|
2013-09-11 20:29:06 -06:00
|
|
|
struct kobject *kobj = &dev->kobj;
|
2007-07-18 02:43:47 -06:00
|
|
|
char *old_device_name = NULL;
|
2006-07-03 15:31:12 -06:00
|
|
|
int error;
|
|
|
|
|
|
|
|
dev = get_device(dev);
|
|
|
|
if (!dev)
|
|
|
|
return -EINVAL;
|
|
|
|
|
2013-10-13 08:12:35 -06:00
|
|
|
dev_dbg(dev, "renaming to %s\n", new_name);
|
2006-07-03 15:31:12 -06:00
|
|
|
|
2009-01-25 07:17:37 -07:00
|
|
|
old_device_name = kstrdup(dev_name(dev), GFP_KERNEL);
|
2007-07-18 02:43:47 -06:00
|
|
|
if (!old_device_name) {
|
|
|
|
error = -ENOMEM;
|
|
|
|
goto out;
|
2006-07-03 15:31:12 -06:00
|
|
|
}
|
|
|
|
|
2010-03-30 12:31:29 -06:00
|
|
|
if (dev->class) {
|
2013-09-11 20:29:06 -06:00
|
|
|
error = sysfs_rename_link_ns(&dev->class->p->subsys.kobj,
|
|
|
|
kobj, old_device_name,
|
|
|
|
new_name, kobject_namespace(kobj));
|
2010-03-30 12:31:29 -06:00
|
|
|
if (error)
|
|
|
|
goto out;
|
|
|
|
}
|
2010-09-04 23:33:14 -06:00
|
|
|
|
2013-09-11 20:29:06 -06:00
|
|
|
error = kobject_rename(kobj, new_name);
|
2009-01-25 07:17:37 -07:00
|
|
|
if (error)
|
2007-07-18 02:43:47 -06:00
|
|
|
goto out;
|
2006-07-03 15:31:12 -06:00
|
|
|
|
2007-07-18 02:43:47 -06:00
|
|
|
out:
|
2006-07-03 15:31:12 -06:00
|
|
|
put_device(dev);
|
|
|
|
|
2007-07-18 02:43:47 -06:00
|
|
|
kfree(old_device_name);
|
2006-07-03 15:31:12 -06:00
|
|
|
|
|
|
|
return error;
|
|
|
|
}
|
2007-02-28 04:38:31 -07:00
|
|
|
EXPORT_SYMBOL_GPL(device_rename);
|
2006-11-20 09:07:51 -07:00
|
|
|
|
|
|
|
static int device_move_class_links(struct device *dev,
|
|
|
|
struct device *old_parent,
|
|
|
|
struct device *new_parent)
|
|
|
|
{
|
2007-03-06 13:55:53 -07:00
|
|
|
int error = 0;
|
2006-11-20 09:07:51 -07:00
|
|
|
|
2007-03-06 13:55:53 -07:00
|
|
|
if (old_parent)
|
|
|
|
sysfs_remove_link(&dev->kobj, "device");
|
|
|
|
if (new_parent)
|
|
|
|
error = sysfs_create_link(&dev->kobj, &new_parent->kobj,
|
|
|
|
"device");
|
|
|
|
return error;
|
2006-11-20 09:07:51 -07:00
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* device_move - moves a device to a new parent
|
|
|
|
* @dev: the pointer to the struct device to be moved
|
2007-01-08 12:16:44 -07:00
|
|
|
* @new_parent: the new parent of the device (can by NULL)
|
2009-03-04 04:44:00 -07:00
|
|
|
* @dpm_order: how to reorder the dpm_list
|
2006-11-20 09:07:51 -07:00
|
|
|
*/
|
2009-03-04 04:44:00 -07:00
|
|
|
int device_move(struct device *dev, struct device *new_parent,
|
|
|
|
enum dpm_order dpm_order)
|
2006-11-20 09:07:51 -07:00
|
|
|
{
|
|
|
|
int error;
|
|
|
|
struct device *old_parent;
|
2007-01-08 12:16:44 -07:00
|
|
|
struct kobject *new_parent_kobj;
|
2006-11-20 09:07:51 -07:00
|
|
|
|
|
|
|
dev = get_device(dev);
|
|
|
|
if (!dev)
|
|
|
|
return -EINVAL;
|
|
|
|
|
2009-03-04 04:44:00 -07:00
|
|
|
device_pm_lock();
|
2006-11-20 09:07:51 -07:00
|
|
|
new_parent = get_device(new_parent);
|
2008-01-24 23:50:12 -07:00
|
|
|
new_parent_kobj = get_device_parent(dev, new_parent);
|
2008-01-21 08:09:44 -07:00
|
|
|
|
2008-10-29 18:36:48 -06:00
|
|
|
pr_debug("device: '%s': %s: moving to '%s'\n", dev_name(dev),
|
|
|
|
__func__, new_parent ? dev_name(new_parent) : "<NULL>");
|
2007-01-08 12:16:44 -07:00
|
|
|
error = kobject_move(&dev->kobj, new_parent_kobj);
|
2006-11-20 09:07:51 -07:00
|
|
|
if (error) {
|
2008-01-21 08:09:44 -07:00
|
|
|
cleanup_glue_dir(dev, new_parent_kobj);
|
2006-11-20 09:07:51 -07:00
|
|
|
put_device(new_parent);
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
old_parent = dev->parent;
|
|
|
|
dev->parent = new_parent;
|
|
|
|
if (old_parent)
|
2008-12-16 13:24:56 -07:00
|
|
|
klist_remove(&dev->p->knode_parent);
|
2008-02-19 04:20:41 -07:00
|
|
|
if (new_parent) {
|
2008-12-16 13:24:56 -07:00
|
|
|
klist_add_tail(&dev->p->knode_parent,
|
|
|
|
&new_parent->p->klist_children);
|
2008-02-19 04:20:41 -07:00
|
|
|
set_dev_node(dev, dev_to_node(new_parent));
|
|
|
|
}
|
|
|
|
|
2012-04-23 01:16:36 -06:00
|
|
|
if (dev->class) {
|
|
|
|
error = device_move_class_links(dev, old_parent, new_parent);
|
|
|
|
if (error) {
|
|
|
|
/* We ignore errors on cleanup since we're hosed anyway... */
|
|
|
|
device_move_class_links(dev, new_parent, old_parent);
|
|
|
|
if (!kobject_move(&dev->kobj, &old_parent->kobj)) {
|
|
|
|
if (new_parent)
|
|
|
|
klist_remove(&dev->p->knode_parent);
|
|
|
|
dev->parent = old_parent;
|
|
|
|
if (old_parent) {
|
|
|
|
klist_add_tail(&dev->p->knode_parent,
|
|
|
|
&old_parent->p->klist_children);
|
|
|
|
set_dev_node(dev, dev_to_node(old_parent));
|
|
|
|
}
|
2008-02-19 04:20:41 -07:00
|
|
|
}
|
2012-04-23 01:16:36 -06:00
|
|
|
cleanup_glue_dir(dev, new_parent_kobj);
|
|
|
|
put_device(new_parent);
|
|
|
|
goto out;
|
2006-11-20 09:07:51 -07:00
|
|
|
}
|
|
|
|
}
|
2009-03-04 04:44:00 -07:00
|
|
|
switch (dpm_order) {
|
|
|
|
case DPM_ORDER_NONE:
|
|
|
|
break;
|
|
|
|
case DPM_ORDER_DEV_AFTER_PARENT:
|
|
|
|
device_pm_move_after(dev, new_parent);
|
|
|
|
break;
|
|
|
|
case DPM_ORDER_PARENT_BEFORE_DEV:
|
|
|
|
device_pm_move_before(new_parent, dev);
|
|
|
|
break;
|
|
|
|
case DPM_ORDER_DEV_LAST:
|
|
|
|
device_pm_move_last(dev);
|
|
|
|
break;
|
|
|
|
}
|
2012-04-23 01:16:36 -06:00
|
|
|
|
2006-11-20 09:07:51 -07:00
|
|
|
put_device(old_parent);
|
|
|
|
out:
|
2009-03-04 04:44:00 -07:00
|
|
|
device_pm_unlock();
|
2006-11-20 09:07:51 -07:00
|
|
|
put_device(dev);
|
|
|
|
return error;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(device_move);
|
2007-11-26 23:11:55 -07:00
|
|
|
|
|
|
|
/**
|
|
|
|
* device_shutdown - call ->shutdown() on each device to shutdown.
|
|
|
|
*/
|
|
|
|
void device_shutdown(void)
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{
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2013-09-24 21:05:11 -06:00
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struct device *dev, *parent;
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2010-03-22 11:36:37 -06:00
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spin_lock(&devices_kset->list_lock);
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/*
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* Walk the devices list backward, shutting down each in turn.
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* Beware that device unplug events may also start pulling
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* devices offline, even as the system is shutting down.
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*/
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while (!list_empty(&devices_kset->list)) {
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dev = list_entry(devices_kset->list.prev, struct device,
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kobj.entry);
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2012-06-22 04:01:40 -06:00
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/*
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* hold reference count of device's parent to
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* prevent it from being freed because parent's
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* lock is to be held
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*/
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2013-09-24 21:05:11 -06:00
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parent = get_device(dev->parent);
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2010-03-22 11:36:37 -06:00
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get_device(dev);
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/*
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* Make sure the device is off the kset list, in the
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* event that dev->*->shutdown() doesn't remove it.
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*/
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list_del_init(&dev->kobj.entry);
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spin_unlock(&devices_kset->list_lock);
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2011-12-06 15:24:52 -07:00
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2012-06-22 04:01:40 -06:00
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/* hold lock to avoid race with probe/release */
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2013-09-24 21:05:11 -06:00
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if (parent)
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device_lock(parent);
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2012-06-22 04:01:40 -06:00
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device_lock(dev);
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2011-12-06 15:24:52 -07:00
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/* Don't allow any more runtime suspends */
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pm_runtime_get_noresume(dev);
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pm_runtime_barrier(dev);
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2007-11-26 23:11:55 -07:00
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if (dev->bus && dev->bus->shutdown) {
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2012-11-23 00:14:12 -07:00
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if (initcall_debug)
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dev_info(dev, "shutdown\n");
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2007-11-26 23:11:55 -07:00
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dev->bus->shutdown(dev);
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} else if (dev->driver && dev->driver->shutdown) {
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2012-11-23 00:14:12 -07:00
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if (initcall_debug)
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dev_info(dev, "shutdown\n");
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2007-11-26 23:11:55 -07:00
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dev->driver->shutdown(dev);
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}
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2012-06-22 04:01:40 -06:00
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device_unlock(dev);
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2013-09-24 21:05:11 -06:00
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if (parent)
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device_unlock(parent);
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2012-06-22 04:01:40 -06:00
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2010-03-22 11:36:37 -06:00
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put_device(dev);
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2013-09-24 21:05:11 -06:00
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put_device(parent);
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2010-03-22 11:36:37 -06:00
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spin_lock(&devices_kset->list_lock);
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2007-11-26 23:11:55 -07:00
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}
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2010-03-22 11:36:37 -06:00
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spin_unlock(&devices_kset->list_lock);
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2007-11-26 23:11:55 -07:00
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}
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2010-06-26 19:02:34 -06:00
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/*
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* Device logging functions
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*/
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#ifdef CONFIG_PRINTK
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2012-09-12 21:14:11 -06:00
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static int
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create_syslog_header(const struct device *dev, char *hdr, size_t hdrlen)
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2010-06-26 19:02:34 -06:00
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{
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2012-05-02 18:29:59 -06:00
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const char *subsys;
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2012-09-12 21:11:29 -06:00
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size_t pos = 0;
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2010-06-26 19:02:34 -06:00
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2012-05-02 18:29:59 -06:00
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if (dev->class)
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subsys = dev->class->name;
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else if (dev->bus)
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subsys = dev->bus->name;
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else
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2012-09-12 21:11:29 -06:00
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return 0;
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2012-05-02 18:29:59 -06:00
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2012-09-12 21:11:29 -06:00
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pos += snprintf(hdr + pos, hdrlen - pos, "SUBSYSTEM=%s", subsys);
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2012-05-02 18:29:59 -06:00
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/*
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* Add device identifier DEVICE=:
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* b12:8 block dev_t
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* c127:3 char dev_t
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* n8 netdev ifindex
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* +sound:card0 subsystem:devname
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*/
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if (MAJOR(dev->devt)) {
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char c;
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if (strcmp(subsys, "block") == 0)
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c = 'b';
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else
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c = 'c';
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2012-09-12 21:11:29 -06:00
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pos++;
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pos += snprintf(hdr + pos, hdrlen - pos,
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"DEVICE=%c%u:%u",
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c, MAJOR(dev->devt), MINOR(dev->devt));
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2012-05-02 18:29:59 -06:00
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} else if (strcmp(subsys, "net") == 0) {
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struct net_device *net = to_net_dev(dev);
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2012-09-12 21:11:29 -06:00
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pos++;
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pos += snprintf(hdr + pos, hdrlen - pos,
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"DEVICE=n%u", net->ifindex);
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2012-05-02 18:29:59 -06:00
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} else {
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2012-09-12 21:11:29 -06:00
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pos++;
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pos += snprintf(hdr + pos, hdrlen - pos,
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"DEVICE=+%s:%s", subsys, dev_name(dev));
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2012-05-02 18:29:59 -06:00
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}
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drivers-core: make structured logging play nice with dynamic-debug
commit c4e00daaa96d3a0786f1f4fe6456281c60ef9a16 changed __dev_printk
in a way that broke dynamic-debug's ability to control the dynamic
prefix of dev_dbg(dev,..), but not dev_dbg(NULL,..) or pr_debug(..),
which is why it wasnt noticed sooner.
When dev==NULL, __dev_printk() just calls printk(), which just works.
But otherwise, it assumed that level was always a string like "<L>"
and just plucked out the 'L', ignoring the rest. However,
dynamic_emit_prefix() adds "[tid] module:func:line:" to the string,
those additions all got lost.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Cc: stable <stable@vger.kernel.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-19 13:46:21 -06:00
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|
2012-09-12 21:11:29 -06:00
|
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return pos;
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}
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|
2012-09-12 21:13:37 -06:00
|
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|
int dev_vprintk_emit(int level, const struct device *dev,
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|
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const char *fmt, va_list args)
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|
|
{
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|
|
char hdr[128];
|
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|
|
size_t hdrlen;
|
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|
|
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|
|
hdrlen = create_syslog_header(dev, hdr, sizeof(hdr));
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|
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|
return vprintk_emit(0, level, hdrlen ? hdr : NULL, hdrlen, fmt, args);
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}
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|
EXPORT_SYMBOL(dev_vprintk_emit);
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|
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|
int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
|
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|
|
{
|
|
|
|
va_list args;
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|
|
int r;
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|
|
|
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|
|
va_start(args, fmt);
|
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|
|
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|
|
r = dev_vprintk_emit(level, dev, fmt, args);
|
|
|
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|
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|
|
va_end(args);
|
|
|
|
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|
|
|
return r;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(dev_printk_emit);
|
|
|
|
|
2012-09-12 21:11:29 -06:00
|
|
|
static int __dev_printk(const char *level, const struct device *dev,
|
|
|
|
struct va_format *vaf)
|
|
|
|
{
|
|
|
|
if (!dev)
|
|
|
|
return printk("%s(NULL device *): %pV", level, vaf);
|
|
|
|
|
2012-09-12 21:14:11 -06:00
|
|
|
return dev_printk_emit(level[1] - '0', dev,
|
|
|
|
"%s %s: %pV",
|
|
|
|
dev_driver_string(dev), dev_name(dev), vaf);
|
2010-06-26 19:02:34 -06:00
|
|
|
}
|
|
|
|
|
|
|
|
int dev_printk(const char *level, const struct device *dev,
|
|
|
|
const char *fmt, ...)
|
|
|
|
{
|
|
|
|
struct va_format vaf;
|
|
|
|
va_list args;
|
|
|
|
int r;
|
|
|
|
|
|
|
|
va_start(args, fmt);
|
|
|
|
|
|
|
|
vaf.fmt = fmt;
|
|
|
|
vaf.va = &args;
|
|
|
|
|
|
|
|
r = __dev_printk(level, dev, &vaf);
|
2012-09-12 21:11:29 -06:00
|
|
|
|
2010-06-26 19:02:34 -06:00
|
|
|
va_end(args);
|
|
|
|
|
|
|
|
return r;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(dev_printk);
|
|
|
|
|
|
|
|
#define define_dev_printk_level(func, kern_level) \
|
|
|
|
int func(const struct device *dev, const char *fmt, ...) \
|
|
|
|
{ \
|
|
|
|
struct va_format vaf; \
|
|
|
|
va_list args; \
|
|
|
|
int r; \
|
|
|
|
\
|
|
|
|
va_start(args, fmt); \
|
|
|
|
\
|
|
|
|
vaf.fmt = fmt; \
|
|
|
|
vaf.va = &args; \
|
|
|
|
\
|
|
|
|
r = __dev_printk(kern_level, dev, &vaf); \
|
2012-09-12 21:11:29 -06:00
|
|
|
\
|
2010-06-26 19:02:34 -06:00
|
|
|
va_end(args); \
|
|
|
|
\
|
|
|
|
return r; \
|
|
|
|
} \
|
|
|
|
EXPORT_SYMBOL(func);
|
|
|
|
|
|
|
|
define_dev_printk_level(dev_emerg, KERN_EMERG);
|
|
|
|
define_dev_printk_level(dev_alert, KERN_ALERT);
|
|
|
|
define_dev_printk_level(dev_crit, KERN_CRIT);
|
|
|
|
define_dev_printk_level(dev_err, KERN_ERR);
|
|
|
|
define_dev_printk_level(dev_warn, KERN_WARNING);
|
|
|
|
define_dev_printk_level(dev_notice, KERN_NOTICE);
|
|
|
|
define_dev_printk_level(_dev_info, KERN_INFO);
|
|
|
|
|
|
|
|
#endif
|