- Use klist iterator in device_for_each_child(), making it safe to use for
removing devices.
- Remove unused list_to_dev() function.
- Kills all usage of devices_subsys.rwsem.
Signed-off-by: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
- Can't wait on removing the current item in the list (the positive refcount *because*
we are using it causes it to deadlock).
Signed-off-by: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
- Don't add devices to bus's embedded kset, since it's not used by anyone anymore.
- Don't need to take the bus rwsem when calling {device,driver}_attach(), since
those functions use the klists and the klists' spinlocks.
Signed-off-by: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
- Now possible, since the lists are locked using the klist lock and not the
global rwsem.
Signed-off-by: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
- Use it in driver_for_each_device() instead of the regular list_head and stop using
the bus's rwsem for protection.
- Use driver_for_each_device() in driver_detach() so we don't deadlock on the
bus's rwsem.
- Remove ->devices.
- Move klist access and sysfs link access out from under device's semaphore, since
they're synchronized through other means.
Signed-off-by: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
- Use it in bus_for_each_drv().
- Use the klist spinlock instead of the bus rwsem.
Signed-off-by: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
- Use it for bus_for_each_dev().
- Use the klist spinlock instead of the bus rwsem.
Signed-off-by: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This klist interface provides a couple of structures that wrap around
struct list_head to provide explicit list "head" (struct klist) and
list "node" (struct klist_node) objects. For struct klist, a spinlock
is included that protects access to the actual list itself. struct
klist_node provides a pointer to the klist that owns it and a kref
reference count that indicates the number of current users of that node
in the list.
The entire point is to provide an interface for iterating over a list
that is safe and allows for modification of the list during the
iteration (e.g. insertion and removal), including modification of the
current node on the list.
It works using a 3rd object type - struct klist_iter - that is declared
and initialized before an iteration. klist_next() is used to acquire the
next element in the list. It returns NULL if there are no more items.
This klist interface provides a couple of structures that wrap around
struct list_head to provide explicit list "head" (struct klist) and
list "node" (struct klist_node) objects. For struct klist, a spinlock
is included that protects access to the actual list itself. struct
klist_node provides a pointer to the klist that owns it and a kref
reference count that indicates the number of current users of that node
in the list.
The entire point is to provide an interface for iterating over a list
that is safe and allows for modification of the list during the
iteration (e.g. insertion and removal), including modification of the
current node on the list.
It works using a 3rd object type - struct klist_iter - that is declared
and initialized before an iteration. klist_next() is used to acquire the
next element in the list. It returns NULL if there are no more items.
Internally, that routine takes the klist's lock, decrements the reference
count of the previous klist_node and increments the count of the next
klist_node. It then drops the lock and returns.
There are primitives for adding and removing nodes to/from a klist.
When deleting, klist_del() will simply decrement the reference count.
Only when the count goes to 0 is the node removed from the list.
klist_remove() will try to delete the node from the list and block
until it is actually removed. This is useful for objects (like devices)
that have been removed from the system and must be freed (but must wait
until all accessors have finished).
Internally, that routine takes the klist's lock, decrements the reference
count of the previous klist_node and increments the count of the next
klist_node. It then drops the lock and returns.
There are primitives for adding and removing nodes to/from a klist.
When deleting, klist_del() will simply decrement the reference count.
Only when the count goes to 0 is the node removed from the list.
klist_remove() will try to delete the node from the list and block
until it is actually removed. This is useful for objects (like devices)
that have been removed from the system and must be freed (but must wait
until all accessors have finished).
Signed-off-by: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff -Nru a/include/linux/klist.h b/include/linux/klist.h
Now there's an iterator for accessing each device bound to a driver.
Signed-off-by: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Index: linux-2.6.12-rc2/drivers/base/driver.c
===================================================================
This relocates the driver binding/unbinding code to drivers/base/dd.c. This is done
for two reasons: One, it's not code related to the bus_type itself; it uses some from
that, some from devices, and some from drivers. And Two, it will make it easier to do
some of the upcoming lock removal on that code..
Signed-off-by: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This adds a per-device semaphore that is taken before every call from the core to a
driver method. This prevents e.g. simultaneous calls to the ->suspend() or ->resume()
and ->probe() or ->release(), potentially saving a whole lot of headaches.
It also moves us a step closer to removing the bus rwsem, since it protects the fields
in struct device that are modified by the core.
Signed-off-by: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Due to the removal of class_simple.c, "make mandocs" no longer works.
This patch fixes this issue.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Trivial fix to USB class-creation error path; please apply.
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
One step on improving the class api so that it can not be used incorrectly.
This also fixes the module owner issue with the dev files that happened when
the devt logic moved to the class core.
Based on a patch originally written by Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
sysfs: fix the rest of the kernel so if an attribute doesn't
implement show or store method read/write will return
-EIO instead of 0 or -EINVAL or -EPERM.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
sysfs: fix drivers/block so if an attribute doesn't implement
show or store method read/write will return -EIO
instead of 0 or -EINVAL.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
sysfs: fix drivers/pci so if an attribute does not implement
show or store method read/write will return -EIO
instead of 0.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
sysfs: fix drivers/base so if an attribute doesn't implement
show or store method read/write will return -EIO
instead of 0.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
sysfs: if attribute does not implement show or store method
read/write should return -EIO instead of 0 or -EINVAL.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Driver core:
change driver's, bus's, class's and platform device's names
to be const char * so one can use
const char *drv_name = "asdfg";
when initializing structures.
Also kill couple of whitespaces.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
kobject: make kobject's name const char * since users should not
attempt to change it (except by calling kobject_rename).
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
