Currently function disable_device() detects slot state by checking
existence of PCI function 0. It's unreliable because the PCI device
for function 0 may be removed through the sysfs interface. If that
happens, it will cause powering off a hotplug slot without destroying
all PCI devices.
On the other hand, it won't hurt us except wasting some computation
power if the check is removed, because all code of disable_device()
is self-protected. So remove the check.
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>
Function acpiphp_sanitize_bus() may call pci_stop_and_remove_bus_device(),
which in turn may remove device from bus->devices list. So walk the
bus->devices list with list_for_each_entry_safe().
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Jiang Liu <jiang.liu@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>
Host bridge hotplug
- Major overhaul of ACPI host bridge add/start (Rafael Wysocki, Yinghai Lu)
- Major overhaul of PCI/ACPI binding (Rafael Wysocki, Yinghai Lu)
- Split out ACPI host bridge and ACPI PCI device hotplug (Yinghai Lu)
- Stop caching _PRT and make independent of bus numbers (Yinghai Lu)
PCI device hotplug
- Clean up cpqphp dead code (Sasha Levin)
- Disable ARI unless device and upstream bridge support it (Yijing Wang)
- Initialize all hot-added devices (not functions 0-7) (Yijing Wang)
Power management
- Don't touch ASPM if disabled (Joe Lawrence)
- Fix ASPM link state management (Myron Stowe)
Miscellaneous
- Fix PCI_EXP_FLAGS accessor (Alex Williamson)
- Disable Bus Master in pci_device_shutdown (Konstantin Khlebnikov)
- Document hotplug resource and MPS parameters (Yijing Wang)
- Add accessor for PCIe capabilities (Myron Stowe)
- Drop pciehp suspend/resume messages (Paul Bolle)
- Make pci_slot built-in only (not a module) (Jiang Liu)
- Remove unused PCI/ACPI bind ops (Jiang Liu)
- Removed used pci_root_bus (Bjorn Helgaas)
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.11 (GNU/Linux)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=ER3b
-----END PGP SIGNATURE-----
Merge tag 'pci-v3.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI changes from Bjorn Helgaas:
"Host bridge hotplug
- Major overhaul of ACPI host bridge add/start (Rafael Wysocki, Yinghai Lu)
- Major overhaul of PCI/ACPI binding (Rafael Wysocki, Yinghai Lu)
- Split out ACPI host bridge and ACPI PCI device hotplug (Yinghai Lu)
- Stop caching _PRT and make independent of bus numbers (Yinghai Lu)
PCI device hotplug
- Clean up cpqphp dead code (Sasha Levin)
- Disable ARI unless device and upstream bridge support it (Yijing Wang)
- Initialize all hot-added devices (not functions 0-7) (Yijing Wang)
Power management
- Don't touch ASPM if disabled (Joe Lawrence)
- Fix ASPM link state management (Myron Stowe)
Miscellaneous
- Fix PCI_EXP_FLAGS accessor (Alex Williamson)
- Disable Bus Master in pci_device_shutdown (Konstantin Khlebnikov)
- Document hotplug resource and MPS parameters (Yijing Wang)
- Add accessor for PCIe capabilities (Myron Stowe)
- Drop pciehp suspend/resume messages (Paul Bolle)
- Make pci_slot built-in only (not a module) (Jiang Liu)
- Remove unused PCI/ACPI bind ops (Jiang Liu)
- Removed used pci_root_bus (Bjorn Helgaas)"
* tag 'pci-v3.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (51 commits)
PCI/ACPI: Don't cache _PRT, and don't associate them with bus numbers
PCI: Fix PCI Express Capability accessors for PCI_EXP_FLAGS
ACPI / PCI: Make pci_slot built-in only, not a module
PCI/PM: Clear state_saved during suspend
PCI: Use atomic_inc_return() rather than atomic_add_return()
PCI: Catch attempts to disable already-disabled devices
PCI: Disable Bus Master unconditionally in pci_device_shutdown()
PCI: acpiphp: Remove dead code for PCI host bridge hotplug
PCI: acpiphp: Create companion ACPI devices before creating PCI devices
PCI: Remove unused "rc" in virtfn_add_bus()
PCI: pciehp: Drop suspend/resume ENTRY messages
PCI/ASPM: Don't touch ASPM if forcibly disabled
PCI/ASPM: Deallocate upstream link state even if device is not PCIe
PCI: Document MPS parameters pci=pcie_bus_safe, pci=pcie_bus_perf, etc
PCI: Document hpiosize= and hpmemsize= resource reservation parameters
PCI: Use PCI Express Capability accessor
PCI: Introduce accessor to retrieve PCIe Capabilities Register
PCI: Put pci_dev in device tree as early as possible
PCI: Skip attaching driver in device_add()
PCI: acpiphp: Keep driver loaded even if no slots found
...
Pull s390 update from Martin Schwidefsky:
"The most prominent change in this patch set is the software dirty bit
patch for s390. It removes __HAVE_ARCH_PAGE_TEST_AND_CLEAR_DIRTY and
the page_test_and_clear_dirty primitive which makes the common memory
management code a bit less obscure.
Heiko fixed most of the PCI related fallout, more often than not
missing GENERIC_HARDIRQS dependencies. Notable is one of the 3270
patches which adds an export to tty_io to be able to resize a tty.
The rest is the usual bunch of cleanups and bug fixes."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (42 commits)
s390/module: Add missing R_390_NONE relocation type
drivers/gpio: add missing GENERIC_HARDIRQ dependency
drivers/input: add couple of missing GENERIC_HARDIRQS dependencies
s390/cleanup: rename SPP to LPP
s390/mm: implement software dirty bits
s390/mm: Fix crst upgrade of mmap with MAP_FIXED
s390/linker skript: discard exit.data at runtime
drivers/media: add missing GENERIC_HARDIRQS dependency
s390/bpf,jit: add vlan tag support
drivers/net,AT91RM9200: add missing GENERIC_HARDIRQS dependency
iucv: fix kernel panic at reboot
s390/Kconfig: sort list of arch selected config options
phylib: remove !S390 dependeny from Kconfig
uio: remove !S390 dependency from Kconfig
dasd: fix sysfs cleanup in dasd_generic_remove
s390/pci: fix hotplug module init
s390/pci: cleanup clp page allocation
s390/pci: cleanup clp inline assembly
s390/perf: cpum_cf: fallback to software sampling events
s390/mm: provide PAGE_SHARED define
...
Loading the pci hotplug module when no devices are present will fail
but unfortunately some hotplug callbacks stay registered to the pci
bus level. Fix this by not letting module loading fail when no pci
devices are present and provide proper {de}registration functions
for these callbacks.
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
pci_probe is too generic and has a name clash with other common code parts.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This changeset is aimed at fixing a few different but related
problems in the ACPI hotplug infrastructure.
First of all, since notify handlers may be run in parallel with
acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device()
and some of them are installed for ACPI handles that have no struct
acpi_device objects attached (i.e. before those objects are created),
those notify handlers have to take acpi_scan_lock to prevent races
from taking place (e.g. a struct acpi_device is found to be present
for the given ACPI handle, but right after that it is removed by
acpi_bus_trim() running in parallel to the given notify handler).
Moreover, since some of them call acpi_bus_scan() and
acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock
should be acquired by the callers of these two funtions rather by
these functions themselves.
For these reasons, make all notify handlers that can handle device
addition and eject events take acpi_scan_lock and remove the
acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim().
Accordingly, update all of their users to make sure that they
are always called under acpi_scan_lock.
Furthermore, since eject operations are carried out asynchronously
with respect to the notify events that trigger them, with the help
of acpi_bus_hot_remove_device(), even if notify handlers take the
ACPI scan lock, it still is possible that, for example,
acpi_bus_trim() will run between acpi_bus_hot_remove_device() and
the notify handler that scheduled its execution and that
acpi_bus_trim() will remove the device node passed to
acpi_bus_hot_remove_device() for ejection. In that case, the struct
acpi_device object obtained by acpi_bus_hot_remove_device() will be
invalid and not-so-funny things will ensue. To protect agaist that,
make the users of acpi_bus_hot_remove_device() run get_device() on
ACPI device node objects that are about to be passed to it and make
acpi_bus_hot_remove_device() run put_device() on them and check if
their ACPI handles are not NULL (make acpi_device_unregister() clear
the device nodes' ACPI handles for that check to work).
Finally, observe that acpi_os_hotplug_execute() actually can fail,
in which case its caller ought to free memory allocated for the
context object to prevent leaks from happening. It also needs to
run put_device() on the device node that it ran get_device() on
previously in that case. Modify the code accordingly.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Commit 668192b678 "PCI: acpiphp: Move host bridge hotplug
to pci_root.c" has moved PCI host bridge hotplug logic from acpiphp
to pci_root, but there is still PCI host bridge hotplug related
dead code left in acpiphp. So remove those dead code.
Now companion ACPI devices are always created before corresponding
PCI devices. And the ACPI event handle_hotplug_event_bridge() will be
installed only if it has associated PCI device. So remove dead code to
handle bridge hot-adding in function handle_hotplug_event_bridge().
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
With commit 4f535093cf "PCI: Put pci_dev in device tree as
early as possible", companion ACPI devices should be created before
creating corresponding PCI devices, otherwise it will break the ACPI
PCI binding logic.
Without this patch, the /sys/bus/pci/devices/.../firmware_node symlink
is missing after hot-removing and hot-adding a device with acpiphp.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
In each suspend and resume cycle my laptop prints these messages at
KERN_INFO level:
pciehp 0000:00:1c.1:pcie04: pciehp_suspend ENTRY
pciehp 0000:00:1c.0:pcie04: pciehp_suspend ENTRY
and
pciehp 0000:00:1c.0:pcie04: pciehp_resume ENTRY
pciehp 0000:00:1c.1:pcie04: pciehp_resume ENTRY
Drop these messages, that were probably used to debug the suspend and
resume code, but now serve no purpose.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
* pci/yinghai-root-bus-hotplug:
PCI: Put pci_dev in device tree as early as possible
PCI: Skip attaching driver in device_add()
PCI: acpiphp: Keep driver loaded even if no slots found
PCI/ACPI: Print info if host bridge notify handler installation fails
PCI: acpiphp: Move host bridge hotplug to pci_root.c
PCI/ACPI: acpiphp: Rename alloc_acpiphp_hp_work() to alloc_acpi_hp_work()
PCI: Make device create/destroy logic symmetric
PCI: Fix reference count leak in pci_dev_present()
PCI: Set pci_dev dev_node early so IOAPIC irq_descs are allocated locally
PCI: Add root bus children dev's res to fail list
PCI: acpiphp: Add is_hotplug_bridge detection
Conflicts:
drivers/pci/pci.h
* pci/acpi-scan2:
ACPI / scan: Drop acpi_bus_add() and use acpi_bus_scan() instead
ACPI: update ej_event interface to take acpi_device
ACPI / scan: Add second pass to acpi_bus_trim()
ACPI / scan: Change the implementation of acpi_bus_trim()
ACPI / scan: Drop the second argument of acpi_bus_trim()
ACPI / scan: Drop the second argument of acpi_device_unregister()
ACPI: Remove the ops field from struct acpi_device
ACPI: remove unused acpi_op_bind and acpi_op_unbind
ACPI / scan: Fix check of device_attach() return value.
* pci/yijing-ari:
PCI: shpchp: Iterate over all devices in slot, not functions 0-7
PCI: sgihp: Iterate over all devices in slot, not functions 0-7
PCI: cpcihp: Iterate over all devices in slot, not functions 0-7
PCI: pciehp: Iterate over all devices in slot, not functions 0-7
PCI: Consolidate "next-function" functions
PCI: Rename pci_enable_ari() to pci_configure_ari()
PCI: Enable ARI if dev and upstream bridge support it; disable otherwise
Since acpi_bus_trim() cannot fail, change its definition to a void
function, so that its callers don't check the return value in vain
and update the callers.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Acked-by: Toshi Kani <toshi.kani@hp.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>
The acpiphp driver is confusing because it contains partial support for PCI
host bridge hotplug as well as support for hotplug of PCI devices.
This patch moves the host bridge hot-add support to pci_root.c and adds
hot-remove support in pci_root.c.
How to test it: if sci_emu patch is applied, find out root bus number to
ACPI root name mapping from dmesg or /sys. To remove root bus:
echo "\_SB.PCIB 3" > /sys/kernel/debug/acpi/sci_notify
To add back root bus:
echo "\_SB.PCIB 1" > /sys/kernel/debug/acpi/sci_notify
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>
Will need to use it for PCI root bridge hotplug support, so rename
*acpiphp* to *acpi* and move to osc.c. Also make kacpi_hotplug_wq static
after that.
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>
CC: Len Brown <lenb@kernel.org>
CC: linux-acpi@vger.kernel.org
When system support hotplug bridge with children hotplug slots, we need
to make sure that parent bridge get preallocated resource so later when
device is plugged into children slot, those children devices will get
resource allocated.
We do not meet this problem, because for PCIe hotplug card, when acpiphp
is used, pci_scan_bridge will set that for us when detect hotplug bit in
slot cap.
Reported-and-tested-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Iterate through devices in a slot by using the upstream bridge's
"bus->devices" list instead of assuming they are functions 0-7. It's
possible there are several slots on the same pci_bus, so restrict it to
only devices matching this slot's device number.
ARI (which allows functions 0-255) is a PCIe-only feature, and this is
a PCI hotplug driver, so we shouldn't find anything other than functions
0-7, but it's better to iterate the same way as other hotplug drivers.
[bhelgaas: changelog, check PCI_SLOT, fix shpchp_unconfigure_device()]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Iterate through devices in a slot by using the upstream bridge's
"bus->devices" list instead of assuming they are functions 0-7. It's
possible there are several slots on the same pci_bus, so restrict it to
only devices matching this slot's device number.
ARI (which allows functions 0-255) is a PCIe-only feature, and this is
a PCI hotplug driver, so we shouldn't find anything other than functions
0-7, but it's better to iterate the same way as other hotplug drivers.
[bhelgaas: changelog, check PCI_SLOT, fix disable_slot()]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Iterate through devices in a slot by using the upstream bridge's
"bus->devices" list instead of assuming they are functions 0-7. It's
possible there are several slots on the same pci_bus, so restrict it to
only devices matching this slot's device number.
ARI (which allows functions 0-255) is a PCIe-only feature, and this is
a PCI hotplug driver, so we shouldn't find anything other than functions
0-7, but it's better to iterate the same way as other hotplug drivers.
[bhelgaas: changelog, check PCI_SLOT, fix cpci_unconfigure_slot()]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Currently, we enumerate devices in a slot with pci_scan_slot(), then
iterate through all the devices we found by looking for functions 0-7. But
that's wrong for ARI devices, which may have function numbers up to 255.
This means that when we hot-add an ARI device, pciehp only initializes
functions 0-7, and other functions don't work correctly. Additionally, if
we hot-remove the device, pciehp only removes functions 0-7, leaving stale
pci_dev structures for any other functions.
This patch fixes the problem by iterating over devices in a slot by using
the upstream bridge's "bus->devices" list instead.
[bhelgaas: changelog]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The only difference between acpi_bus_scan() and acpi_bus_add() is the
invocation of acpi_update_all_gpes() in the latter which in fact is
unnecessary, because acpi_update_all_gpes() has already been called
by acpi_scan_init() and the way it is implemented guarantees the next
invocations of it to do nothing.
For this reason, drop acpi_bus_add() and make all its callers use
acpi_bus_scan() directly instead of it. Additionally, rearrange the
code in acpi_scan_init() slightly to improve the visibility of the
acpi_update_all_gpes() call in there.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
All callers of acpi_bus_trim() pass 1 (true) as the second argument
of it, so remove that argument entirely and change acpi_bus_trim()
to always behave as though it were 1.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
When we have an SHPC-capable bridge with a second SHPC-capable bridge
below it, pushing the upstream bridge's attention button causes a
deadlock.
The deadlock happens because we use the shpchp_wq workqueue to run
shpchp_pushbutton_thread(), which uses shpchp_disable_slot() to remove
devices below the upstream bridge. When we remove the downstream bridge,
we call shpc_remove(), the shpchp driver's .remove() method. That calls
flush_workqueue(shpchp_wq), which deadlocks because the
shpchp_pushbutton_thread() work item is still running.
This patch avoids the deadlock by creating a workqueue for every slot
and removing the single shared workqueue.
Here's the call path that leads to the deadlock:
shpchp_queue_pushbutton_work
queue_work(shpchp_wq) # shpchp_pushbutton_thread
...
shpchp_pushbutton_thread
shpchp_disable_slot
remove_board
shpchp_unconfigure_device
pci_stop_and_remove_bus_device
...
shpc_remove # shpchp driver .remove method
hpc_release_ctlr
cleanup_slots
flush_workqueue(shpchp_wq)
This change is based on code inspection, since we don't have hardware
with this topology.
Based-on-patch-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org
Use non-ordered workqueue for attention button events.
Attention button events on each slot can be handled asynchronously. So
we should use non-ordered workqueue. This patch also removes ordered
workqueue in shpchp as a result.
486b10b9f4 ("PCI: pciehp: Handle push button event asynchronously") made
the same change to pciehp. I split this out from a patch by Yijing Wang
<wangyijing@huawei.com> so we fix one thing at a time and to make the
shpchp history correspond more closely with the pciehp history.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
e24dcbef93 ("shpchp: update workqueue usage") was described as adding
non-ordered shpchp_wq, but it actually made it an *ordered* workqueue.
This patch changes shpchp_wq to be non-ordered, as described in the
e24dcbef93 commit log and as was done for pciehp by a827ea307b ("pciehp:
update workqueue usage").
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
When we have a hotplug-capable PCIe port with a second hotplug-capable
PCIe port below it, removing the device below the upstream port causes
a deadlock.
The deadlock happens because we use the pciehp_wq workqueue to run
pciehp_power_thread(), which uses pciehp_disable_slot() to remove devices
below the upstream port. When we remove the downstream PCIe port, we call
pciehp_remove(), the pciehp driver's .remove() method. That calls
flush_workqueue(pciehp_wq), which deadlocks because the
pciehp_power_thread() work item is still running.
This patch avoids the deadlock by creating a workqueue for every PCIe port
and removing the single shared workqueue.
Here's the call path that leads to the deadlock:
pciehp_queue_pushbutton_work
queue_work(pciehp_wq) # queue pciehp_power_thread
...
pciehp_power_thread
pciehp_disable_slot
remove_board
pciehp_unconfigure_device
pci_stop_and_remove_bus_device
...
pciehp_remove # pciehp driver .remove method
pciehp_release_ctrl
pcie_cleanup_slot
flush_workqueue(pciehp_wq)
This is fairly urgent because it can be caused by simply unplugging a
Thunderbolt adapter, as reported by Daniel below.
[bhelgaas: changelog]
Reference: http://lkml.kernel.org/r/CAMVG2ssiRgcTD1bej2tkUUfsWmpL5eNtPcNif9va2-Gzb2u8nQ@mail.gmail.com
Reported-and-tested-by: Daniel J Blueman <daniel@quora.org>
Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org
* pci/yinghai-survey-resources+acpi-scan:
ACPI / scan: Treat power resources in a special way
ACPI: Remove unused struct acpi_pci_root.id member
ACPI: Drop ACPI device .bind() and .unbind() callbacks
ACPI / PCI: Move the _PRT setup and cleanup code to pci-acpi.c
ACPI / PCI: Rework the setup and cleanup of device wakeup
ACPI: Add .setup() and .cleanup() callbacks to struct acpi_bus_type
ACPI: Make acpi_bus_scan() and acpi_bus_add() take only one argument
ACPI: Replace ACPI device add_type field with a match_driver flag
ACPI: Drop the second argument of acpi_bus_scan()
ACPI: Remove the arguments of acpi_bus_add() that are not used
ACPI: Remove acpi_start_single_object() and acpi_bus_start()
ACPI / PCI: Fold acpi_pci_root_start() into acpi_pci_root_add()
ACPI: Change the ordering of acpi_bus_check_add()
ACPI: Replace struct acpi_bus_ops with enum type
ACPI: Reduce the usage of struct acpi_bus_ops
ACPI: Make acpi_bus_add() and acpi_bus_start() visibly different
ACPI: Change the ordering of PCI root bridge driver registrarion
ACPI: Separate adding ACPI device objects from probing ACPI drivers
The callers of acpi_bus_add() usually assume that if it has
succeeded, then a struct acpi_device object has been attached to
the handle passed as the first argument. Unfortunately, however,
this assumption is wrong, because acpi_bus_scan(), and acpi_bus_add()
too as a result, may return a pointer to a different struct
acpi_device object on success (it may be an object corresponding to
one of the descendant ACPI nodes in the namespace scope below that
handle).
For this reason, the callers of acpi_bus_add() who care about
whether or not a struct acpi_device object has been created for
its first argument need to check that using acpi_bus_get_device()
anyway, so the second argument of acpi_bus_add() is not really
useful for them. The same observation applies to acpi_bus_scan()
executed directly from acpi_scan_init().
Therefore modify the relevant callers of acpi_bus_add() to check the
existence of the struct acpi_device in question with the help of
acpi_bus_get_device() and drop the no longer necessary second
argument of acpi_bus_add(). Accordingly, modify acpi_scan_init() to
use acpi_bus_get_device() to get acpi_root and drop the no longer
needed second argument of acpi_bus_scan().
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Notice that acpi_bus_add() uses only 2 of its 4 arguments and
redefine its header to match the body. Update all of its callers as
necessary and observe that this leads to quite a number of removed
lines of code (Linus will like that).
Add a kerneldoc comment documenting acpi_bus_add() and wonder how
its callers make wrong assumptions about the second argument (make
note to self to take care of that later).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
The ACPI PCI root bridge driver was the only ACPI driver implementing
the .start() callback, which isn't used by any ACPI drivers any more
now.
For this reason, acpi_start_single_object() has no purpose any more,
so remove it and all references to it. Also remove
acpi_bus_start_device(), whose only purpose was to call
acpi_start_single_object().
Moreover, since after the removal of acpi_bus_start_device() the
only purpose of acpi_bus_start() remains to call
acpi_update_all_gpes(), move that into acpi_bus_add() and drop
acpi_bus_start() too, remove its header from acpi_bus.h and
update all of its former users accordingly.
This change was previously proposed in a different from by
Yinghai Lu.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Pull s390 update from Martin Schwidefsky:
"Add support to generate code for the latest machine zEC12, MOD and XOR
instruction support for the BPF jit compiler, the dasd safe offline
feature and the big one: the s390 architecture gets PCI support!!
Right before the world ends on the 21st ;-)"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (41 commits)
s390/qdio: rename the misleading PCI flag of qdio devices
s390/pci: remove obsolete email addresses
s390/pci: speed up __iowrite64_copy by using pci store block insn
s390/pci: enable NEED_DMA_MAP_STATE
s390/pci: no msleep in potential IRQ context
s390/pci: fix potential NULL pointer dereference in dma_free_seg_table()
s390/pci: use kmem_cache_zalloc instead of kmem_cache_alloc/memset
s390/bpf,jit: add support for XOR instruction
s390/bpf,jit: add support MOD instruction
s390/cio: fix pgid reserved check
vga: compile fix, disable vga for s390
s390/pci: add PCI Kconfig options
s390/pci: s390 specific PCI sysfs attributes
s390/pci: PCI hotplug support via SCLP
s390/pci: CHSC PCI support for error and availability events
s390/pci: DMA support
s390/pci: PCI adapter interrupts for MSI/MSI-X
s390/bitops: find leftmost bit instruction support
s390/pci: CLP interface
s390/pci: base support
...
Add SCLP PCI configure/deconfigure and implement a PCI hotplug
controller (s390_pci_hpc). The hotplug controller creates a slot
for every PCI function in stand-by or configured state. The PCI
functions are named after the PCI function ID (fid). By writing to
the power attribute in /sys/bus/pci/slots/<fid>/power the PCI function
is moved to stand-by or configured state. If moved to the configured
state the device is automatically scanned by the s390 PCI layer.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
CONFIG_HOTPLUG is going away as an option so __devexit_p, __devint,
__devinitdata, __devinitconst, and _devexit are no longer needed.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull powerpc updates from Benjamin Herrenschmidt:
"Some highlights in addition to the usual batch of fixes:
- 64TB address space support for 64-bit processes by Aneesh Kumar
- Gavin Shan did a major cleanup & re-organization of our EEH support
code (IBM fancy PCI error handling & recovery infrastructure) which
paves the way for supporting different platform backends, along
with some rework of the PCIe code for the PowerNV platform in order
to remove home made resource allocations and instead use the
generic code (which is possible after some small improvements to it
done by Gavin).
- Uprobes support by Ananth N Mavinakayanahalli
- A pile of embedded updates from Freescale folks, including new SoC
and board supports, more KVM stuff including preparing for 64-bit
BookE KVM support, ePAPR 1.1 updates, etc..."
Fixup trivial conflicts in drivers/scsi/ipr.c
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (146 commits)
powerpc/iommu: Fix multiple issues with IOMMU pools code
powerpc: Fix VMX fix for memcpy case
driver/mtd:IFC NAND:Initialise internal SRAM before any write
powerpc/fsl-pci: use 'Header Type' to identify PCIE mode
powerpc/eeh: Don't release eeh_mutex in eeh_phb_pe_get
powerpc: Remove tlb batching hack for nighthawk
powerpc: Set paca->data_offset = 0 for boot cpu
powerpc/perf: Sample only if SIAR-Valid bit is set in P7+
powerpc/fsl-pci: fix warning when CONFIG_SWIOTLB is disabled
powerpc/mpc85xx: Update interrupt handling for IFC controller
powerpc/85xx: Enable USB support in p1023rds_defconfig
powerpc/smp: Do not disable IPI interrupts during suspend
powerpc/eeh: Fix crash on converting OF node to edev
powerpc/eeh: Lock module while handling EEH event
powerpc/kprobe: Don't emulate store when kprobe stwu r1
powerpc/kprobe: Complete kprobe and migrate exception frame
powerpc/kprobe: Introduce a new thread flag
powerpc: Remove unused __get_user64() and __put_user64()
powerpc/eeh: Global mutex to protect PE tree
powerpc/eeh: Remove EEH PE for normal PCI hotplug
...
Commit 0d52f54e2e (PCI / ACPI: Make acpiphp
ignore root bridges using PCIe native hotplug) added code that made the
acpiphp driver completely ignore PCIe root complexes for which the kernel
had been granted control of the native PCIe hotplug feature by the BIOS
through _OSC. Later commit 619a5182d1
"PCI hotplug: Always allow acpiphp to handle non-PCIe bridges" relaxed
the constraints to allow acpiphp driver handle non-PCIe bridges under
such a complex. The constraint needs to be relaxed further to allow
acpiphp driver to handle PCIe ports without native PCIe hotplug capability.
Some MR-IOV switch chipsets, such PLX8696, support multiple virtual PCIe
switches and may migrate downstream ports among virtual switches. To
migrate a downstream port from the source virtual switch to the target, the
port needs to be hot-removed from the source and hot-added into the target.
The pciehp driver can't be used here because there are no slots within the
virtual PCIe switch. So acpiphp driver is used to support downstream port
migration. A typical configuration is as below:
[Root without native PCIe HP]
[Upstream port of vswitch without native PCIe HP]
[Downstream port of vswitch with native PCIe HP]
[PCIe endpoint]
Here acpiphp driver will be used to handle root ports and upstream port
in the virtual switch, and pciehp driver will be used to handle downstream
ports in the virtual switch.
Signed-off-by: Jiang Liu <liuj97@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
This patch changes .add/.remove interfaces of acpi_pci_driver.
In the current implementation acpi_handle is passed as a parameter
of .add/.remove interface. However, the acpi_pci_root structure
contains more useful information than just the acpi_handle. This
enables us to avoid some useless lookups in each acpi_pci_driver.
Note: This changes interfaces used by acpi_pci_register_driver(), an
exported symbol. This patch updates all the in-kernel users, but any
out-of-kernel acpi_pci_register_driver() users will need updates.
[bhelgaas: changelog]
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Function eeh_rmv_from_parent_pe() could be called by the path of
either normal PCI hotplug, or EEH recovery. For the former case,
we need purge the corresponding PE on removal of the associated
PE bus.
The patch tries to cover that by passing more information to function
pcibios_remove_pci_devices() so that we know if the corresponding PE
needs to be purged or be marked as "invalid".
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* pci/jiang-get-domain-bus-slot:
xen-pcifront: Use hotplug-safe pci_get_domain_bus_and_slot()
PCI: Use hotplug-safe pci_get_domain_bus_and_slot()
PCI/cpcihp: Use hotplug-safe pci_get_domain_bus_and_slot()
PCI/vga: Use hotplug-safe pci_get_domain_bus_and_slot()
ia64/PCI: Use hotplug-safe pci_get_domain_bus_and_slot()
* pci/trivial:
PCI: Drop duplicate const in DECLARE_PCI_FIXUP_SECTION
PCI: Drop bogus default from ARCH_SUPPORTS_MSI
PCI: cpqphp: Remove unreachable path
PCI: Remove bus number resource debug messages
PCI/AER: Print completion message at KERN_INFO to match starting message
PCI: Fix drivers/pci/pci.c kernel-doc warnings
Following code has a race window between pci_find_bus() and pci_get_slot()
if PCI hotplug operation happens between them which removes the pci_bus.
So use PCI hotplug safe interface pci_get_domain_bus_and_slot() instead,
which also reduces code complexity.
struct pci_bus *pci_bus = pci_find_bus(domain, busno);
struct pci_dev *pci_dev = pci_get_slot(pci_bus, devfn);
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
register & 0x0B == 0x04 is never true, the code will always take the
(identical) 0x00 path anyway. Remove the dead code paths.
Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=44151
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Jiang Liu