When a hotplug driver calls pci_hp_register(), all steps necessary for
registration are carried out in one go, including creation of a kobject
and addition to sysfs. That's a problem for pciehp once it's converted
to enable/disable the slot exclusively from the IRQ thread: The thread
needs to be spawned after creation of the kobject (because it uses the
kobject's name), but before addition to sysfs (because it will handle
enable/disable requests submitted via sysfs).
pci_hp_deregister() does offer a ->release callback that's invoked
after deletion from sysfs and before destruction of the kobject. But
because pci_hp_register() doesn't offer a counterpart, hotplug drivers'
->probe and ->remove code becomes asymmetric, which is error prone
as recently discovered use-after-free bugs in pciehp's ->remove hook
have shown.
In a sense, this appears to be a case of the midlayer antipattern:
"The core thesis of the "midlayer mistake" is that midlayers are
bad and should not exist. That common functionality which it is
so tempting to put in a midlayer should instead be provided as
library routines which can [be] used, augmented, or ignored by
each bottom level driver independently. Thus every subsystem
that supports multiple implementations (or drivers) should
provide a very thin top layer which calls directly into the
bottom layer drivers, and a rich library of support code that
eases the implementation of those drivers. This library is
available to, but not forced upon, those drivers."
-- Neil Brown (2009), https://lwn.net/Articles/336262/
The presence of midlayer traits in the PCI hotplug core might be ascribed
to its age: When it was introduced in February 2002, the blessings of a
library approach might not have been well known:
https://git.kernel.org/tglx/history/c/a8a2069f432c
For comparison, the driver core does offer split functions for creating
a kobject (device_initialize()) and addition to sysfs (device_add()) as
an alternative to carrying out everything at once (device_register()).
This was introduced in October 2002:
https://git.kernel.org/tglx/history/c/8b290eb19962
The odd ->release callback in the PCI hotplug core was added in 2003:
https://git.kernel.org/tglx/history/c/69f8d663b595
Clearly, a library approach would not force every hotplug driver to
implement a ->release callback, but rather allow the driver to remove
the sysfs files, release its data structures and finally destroy the
kobject. Alternatively, a driver may choose to remove everything with
pci_hp_deregister(), then release its data structures.
To this end, offer drivers pci_hp_initialize() and pci_hp_add() as a
split-up version of pci_hp_register(). Likewise, offer pci_hp_del()
and pci_hp_destroy() as a split-up version of pci_hp_deregister().
Eliminate the ->release callback and move its code into each driver's
teardown routine.
Declare pci_hp_deregister() void, in keeping with the usual kernel
pattern that enablement can fail, but disablement cannot. It only
returned an error if the caller passed in a NULL pointer or a slot which
has never or is no longer registered or is sharing its name with another
slot. Those would be bugs, so WARN about them. Few hotplug drivers
actually checked the return value and those that did only printed a
useless error message to dmesg. Remove that.
For most drivers the conversion was straightforward since it doesn't
matter whether the code in the ->release callback is executed before or
after destruction of the kobject. But in the case of ibmphp, it was
unclear to me whether setting slot_cur->ctrl and slot_cur->bus_on to
NULL needs to happen before the kobject is destroyed, so I erred on
the side of caution and ensured that the order stays the same. Another
nontrivial case is pnv_php, I've found the list and kref logic difficult
to understand, however my impression was that it is safe to delete the
list element and drop the references until after the kobject is
destroyed.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> # drivers/platform/x86
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Scott Murray <scott@spiteful.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Gavin Shan <gwshan@linux.vnet.ibm.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Corentin Chary <corentin.chary@gmail.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Andy Shevchenko <andy@infradead.org>
Add SPDX GPL-2.0+ to all PCI files that specified the GPL and allowed
either GPL version 2 or any later version.
Remove the boilerplate GPL version 2 or later language, relying on the
assertion in b24413180f ("License cleanup: add SPDX GPL-2.0 license
identifier to files with no license") that the SPDX identifier may be used
instead of the full boilerplate text.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix all whitespace issues (missing or needed whitespace) in all files in
drivers/pci. Code is compiled with allyesconfig before and after code
changes and objects are recorded and checked with objdiff and they are not
changed after this commit.
Signed-off-by: Bogicevic Sasa <brutallesale@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Move EXPORT_SYMBOL so it immediately follows the function or variable.
No functional change.
[bhelgaas: squash similar changes, fix hotplug, probe, rom, search, too]
Signed-off-by: Ryan Desfosses <ryan@desfo.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Multiple race conditions are possible between the ACPI-based PCI hotplug
(ACPIPHP) and the generic PCI bus rescan and device removal that can be
triggered via sysfs.
To avoid those race conditions make the ACPIPHP code use global PCI
rescan-remove locking.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Fix whitespace, capitalization, and spelling errors. No functional change.
I know "busses" is not an error, but "buses" was more common, so I used it
consistently.
Signed-off-by: Marta Rybczynska <rybczynska@gmail.com> (pci_reset_bridge_secondary_bus())
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch is to use pr_debug/info/warn/err to replace acpiphp debug
functions and remove module's debug param.
User interface change: before this patch, boot with the "acpiphp.debug"
kernel parameter to turn on debug. After this patch, set
CONFIG_DYNAMIC_DEBUG=y and boot with "acpiphp.dyndebug=+p" instead.
See Documentation/dynamic-debug-howto.txt.
[bhelgaas: changelog]
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Both acpiphp_disable_slot() and acpiphp_eject_slot() are always
called together so instead of calling each separately we can
consolidate them into one function acpiphp_disable_and_eject_slot()
that does both (but it will return success on _EJ0 failures that
were ignored in the majority of call sites anyway).
[rjw: Rebased plus minor tweaks]
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
To avoid chasing more pointers than necessary in some situations,
move the bridge pointer from struct acpiphp_slot to struct
acpiphp_func (and call it 'parent') and add a bus pointer to
struct acpiphp_slot.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
If the slot unique number is passed as an additional argument to
acpiphp_register_hotplug_slot(), the 'sun' field in struct
acpiphp_slot is only used by ibm_[s|g]et_attention_status(),
but then it's more efficient to store it in struct slot.
Thus move the 'sun' field from struct acpiphp_slot to struct slot
changing its data type to unsigned int in the process, and redefine
acpiphp_register_hotplug_slot() to take the slot number as separate
argument.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Previously the acpiphp driver registered itself as an ACPI PCI subdriver,
so its callbacks were invoked when creating/destroying PCI root
buses to manage ACPI-based PCI hotplug slots. But it doesn't handle
P2P bridge hotplug events, so it will cause strange behaviour if there
are hotplug slots associated with a hot-removed P2P bridge.
This patch fixes this issue by:
1) Directly hooking into PCI core to update hotplug slot devices when
creating/destroying PCI buses through:
pci_{add|remove}_bus() -> acpi_pci_{add|remove}_bus()
2) Getting rid of unused ACPI PCI subdriver-related code
It also cleans up unused code in the acpiphp driver.
[bhelgaas: keep acpi_pci_add_bus() stub for CONFIG_ACPI=n]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Convert acpiphp to be builtin only, with no module option.
Previously, when HOTPLUG_PCI_ACPI=m, users could disable acpiphp by
removing the module or preventing it from loading. That can't be done
if acpiphp is builtin statically, so this adds an "acpiphp.disable"
kernel parameter. If a user needs to use this parameter, it is a bug,
and we want to hear about it.
[bhelgaas: fold in acpiphp.disable here, remove documentation]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Could have root bus hot-added later and there may be slots that need
acpiphp.
The result returned by acpiphp_get_num_slots() is meaningless, because
the bridge the slots are under may be added after this function has been
called, so drop acpiphp_get_num_slots() and the code using it.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Should not have two, just remove debug, and use module_param_named
instead.
Also change acpiphp_debug to bool.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
module_param(bool) used to counter-intuitively take an int. In
fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy
trick.
It's time to remove the int/unsigned int option. For this version
it'll simply give a warning, but it'll break next kernel version.
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Move the max_bus_speed and cur_bus_speed into the pci_bus. Expose the
values through the PCI slot driver instead of the hotplug slot driver.
Update all the hotplug drivers to use the pci_bus instead of their own
data structures.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The "owner" field in struct hotplug_slot_ops is initialized by PCI
hotplug core. So each hotplug controller driver doesn't need to
initialize it.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Reviewed-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Certain HP machines require the full 64 bits of _SUN as allowed
by the ACPI spec. Without this change, we get name collisions in
the lower 32 bits of the _SUN returned by firmware.
Acked-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Justin Chen <justin.chen@hp.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We do not need to manage our own name parameter, especially since
the PCI core can change it on our behalf, in the case of duplicate
slot names.
Remove 'name' from acpiphp's version of struct slot.
Cc: kristen.c.accardi@intel.com
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Update pci_hp_register() to take a const char *name parameter.
The motivation for this is to clean up the individual hotplug
drivers so that each one does not have to manage its own name.
The PCI core should be the place where we manage the name.
We update the interface and all callsites first, in a
"no functional change" manner, and clean up the drivers later.
Cc: kristen.c.accardi@intel.com
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Currently, /sys/bus/pci/slots/ only exposes hotplug attributes when a
hotplug driver is loaded, but PCI slots have attributes such as address,
speed, width, etc. that are not related to hotplug at all.
Introduce pci_slot as the primary data structure and kobject model.
Hotplug attributes described in hotplug_slot become a secondary
structure associated with the pci_slot.
This patch only creates the infrastructure that allows the separation of
PCI slot attributes and hotplug attributes. In this patch, the PCI
hotplug core remains the only user of this infrastructure, and thus,
/sys/bus/pci/slots/ will still only become populated when a hotplug
driver is loaded.
A later patch in this series will add a second user of this new
infrastructure and demonstrate splitting the task of exposing pci_slot
attributes from hotplug_slot attributes.
- Make pci_slot the primary sysfs entity. hotplug_slot becomes a
subsidiary structure.
o pci_create_slot() creates and registers a slot with the PCI core
o pci_slot_add_hotplug() gives it hotplug capability
- Change the prototype of pci_hp_register() to take the bus and
slot number (on parent bus) as parameters.
- Remove all the ->get_address methods since this functionality is
now handled by pci_slot directly.
[achiang@hp.com: rpaphp-correctly-pci_hp_register-for-empty-pci-slots]
Tested-by: Badari Pulavarty <pbadari@us.ibm.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: make headers_check happy]
[akpm@linux-foundation.org: nuther build fix]
[akpm@linux-foundation.org: fix typo in #include]
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Cc: Greg KH <greg@kroah.com>
Cc: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Cc: Len Brown <lenb@kernel.org>
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
On systems where the optional _PS3 ACPI object is not implemented
acpiphp fails to power off the slot. This is happening because the
current code does not attempt to remove power using the _EJ0 ACPI
object. This patch restores the _EJ0 evaluation attempt which was
apparently inadvertently removed from the power-off sequence when the
_EJ0 evaluation code was relocated from power_off_slot() to
acpiphp_eject_slot().
Signed-off-by: Gary Hade <garyhade@us.ibm.com>
Cc: <lcm@us.ibm.com>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.
Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change memory allocation for acpiphp slots
Change the "struct slot" that acpiphp uses for managing it's slots to
directly contain the memory for the needed struct hotplug_slot_info and
the slot's name. This way we need only two memory allocations per slot
instead of four.
While we are at it: make_slot_name() is just a wrapper around snprintf()
knowing the right arguments to call it. Since the function makes just one
function call and is only called from one place I inlined it by hand.
Finally this fixes a possible bug waiting for someone to hit it. There were
two unused local variables in acpiphp_register_hotplug_slot(). gcc did not
find them because they were used in memory allocations with sizeof(*var).
They had the same types as the target of the allocation, but nevertheless
this was just weird.
Signed-off-by: Rolf Eike Beer <eike-hotplug@sf-tec.de>
Acked-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
acpiphp_glue_exit() needs to be called to unwind when no slots found.
(It fixes data corruption when reloading acpiphp driver with no such devices)
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This makes it possible to build pci hotplug drivers outside of the main
kernel tree, and Sam keeps telling me to move local header files to
their proper places...
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add acpiphp to the MAINTAINERS file.
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Modify the acpiphp driver to use the ACPI dock driver for dock
notifications. Only load the acpiphp driver if we find we have pci dock
devices.
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>
o This patch removes IDs (for slots management).
o This patch removes the slot register/unregister processes
from the init/exit phases. Instead, adds these processes
in the bridge add/cleanup phases.
o Currently, this change doesn't have any meanings. But
these changes are needed to support p2p bridge(with
hotplug slot)
Signed-off-by: MUNEDA Takahiro <muneda.takahiro@jp.fujitsu.com>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
These patches add generic dock event handling to acpiphp. If there are
pci devices that need to be inserted/removed after the dock event, the
event notification will be handed down to the normal pci hotplug event
handler in acpiphp so that new bridges/devices can be enumerated.
Because some dock stations do not have pci bridges or pci devices that
need to be inserted after a dock, acpiphp will remain loaded to handle
dock events even if no hotpluggable pci slots are discovered.
You probably need to have the pci=assign-busses kernel parameter enabled
to use these patches, and you may not allow ibm_acpi to handle docking
notifications and use this patch.
This patch incorporates feedback provided by many.
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch converts acpiphp to use the generic PCI resource assignment code.
It's quite large, but most of it is deleting the acpiphp_pci and acpiphp_res
files. It's tested on an hp Integrity rx8620 (which won't work without this
patch). Testers with other hardware welcomed.
Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Lukas Wunner