Some hardware exposes PCIE slots in such a way that they can be claimed
by either the acpiphp or pciehp driver. pciehp is the preferred driver
if the firmware allows the OS to claim control via the _OSC method so
should be loaded first - if it fails to bind (either due to a missing
_OSC method or the firmware refusing to hand off control) then we can
fall back to acpiphp or a vendor-specific driver.
This patch simply changes the link order to ensure that pciehp will be
initialised before acpiphp if both are statically built into the kernel.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
For PCI devices, pci_bus_assign_resources() must be called to set up the
pci_device->resource array before pci_bus_add_devices() can be called, else
attempts to load drivers results in BAR collision errors where there are none.
This is not done in fakephp, so devices can be "unplugged" but scanning the
parent bus won't bring the devices back due to resource unallocation. Move the
pci_bus_add_device-calling logic into pci_rescan_bus and preface it with a call
to pci_bus_assign_resources so that we only have to (re)allocate resources once
per bus where a new device is found.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI hotplug: fix lock imbalance in pciehp
PCI PM: Restore standard config registers of all devices early
PCI/MSI: bugfix/utilize for msi_capability_init()
set_lock_status omits mutex_unlock in fail path. Add the omitted
unlock.
As a result a lockup caused by this can be triggered from userspace
by writing 1 to /sys/bus/pci/slots/.../lock often enough.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
ACPI hotplug panic with current git head
http://lkml.org/lkml/2009/1/10/136
Rather than reverting the entire commit that causes the crash:
e8c331e963
"PCI hotplug: introduce functions for ACPI slot detection"
simply harden against it while the changes to
the hotplug code on this particularl machine are understood.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Len Brown <len.brown@intel.com>
func is checked not to be NULL a few lines before.
A simplified version of the semantic patch that makes this change is as
follows: (http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@r exists@
local idexpression x;
expression E;
position p1,p2;
@@
if (x@p1 == NULL || ...) { ... when forall
return ...; }
... when != \(x=E\|x--\|x++\|--x\|++x\|x-=E\|x+=E\|x|=E\|x&=E\|&x\)
(
x@p2 == NULL
|
x@p2 != NULL
)
// another path to the test that is not through p1?
@s exists@
local idexpression r.x;
position r.p1,r.p2;
@@
... when != x@p1
(
x@p2 == NULL
|
x@p2 != NULL
)
@fix depends on !s@
position r.p1,r.p2;
expression x,E;
statement S1,S2;
@@
(
- if ((x@p2 != NULL) || ...)
S1
|
- if ((x@p2 == NULL) && ...) S1
|
- BUG_ON(x@p2 == NULL);
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Clean up register definitions related to PCI Express Hot plug.
- Add register definitions into include/linux/pci_regs.h, and use
them instead of pciehp's locally definied register definitions.
- Remove pciehp's locally defined register definitions
- Remove unused register definitions in pciehp.
- Some minor cleanups.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Bit 10 in Link Status register used to be defined as Training Error in
the PCI Express 1.0a specification. But it was removed by Training Error
ECN and is no longer defined. So pciehp must ignore the value read from
it.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Some ACPI related PCI hotplug code can be shared among PCI hotplug
drivers. This patch introduces the following functions in
drivers/pci/hotplug/acpi_pcihp.c to share the code, and changes
acpiphp and pciehp to use them.
- int acpi_pci_detect_ejectable(struct pci_bus *pbus)
This checks if the specified PCI bus has ejectable slots.
- int acpi_pci_check_ejectable(struct pci_bus *pbus, acpi_handle handle)
This checks if the specified handle is ejectable ACPI PCI slot. The
'pbus' parameter is needed to check if 'handle' is PCI related ACPI
object.
This patch also introduces the following inline function in
include/linux/pci-acpi.h, which is useful to get ACPI handle of the
PCI bridge from struct pci_bus of the bridge's secondary bus.
- static inline acpi_handle acpi_pci_get_bridge_handle(struct pci_bus *pbus)
This returns ACPI handle of the PCI bridge which generates PCI bus
specified by 'pbus'.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
ACPI based hot-pluggable PCIe slot detection logic was added to
prevent the problem non hot-pluggable PCIe slot was detected as
hot-pluggable. The slot detection logic can be selected through
'pciehp_detect_mode', but it would be better if it is selected
automatically.
This patch adds 'auto' option for 'pciehp_detect_mode'. When it is
specified, pciehp judges which 'acpi' or 'pcie' should be used. It
seems that the physical slot number is duplicated among some slots on
most of the platforms with the above-mentioned problem. So 'auto' mode
uses this information to judge which 'acpi' or 'pcie' should be
used. That is, if duplicated physical slot numbers are detected,
'acpi' mode is used. This method is not perfect, but it's realistic.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
There is a problem that some non hot-pluggable PCIe slots are detected
as hot-pluggable by pciehp on some platforms. The immediate cause of
this problem is that hot-plug capable bit in the Slot Capabilities
register is set even for non hot-pluggable slots on those platforms.
It seems a BIOS/hardware problem, but we need workaround about that.
Some of those platforms define hot-pluggable PCIe slots on ACPI
namespace properly, while hot-plug capable bit in the Slot
Capabilities register is set improperly. So using ACPI namespace
information in pciehp to detect PCIe hot-pluggable slots would be a
workaround.
This patch adds 'pciehp_detect_mode' module option. When 'acpi' is
specified, pciehp uses ACPI namespace information to detect PCIe
hot-pluggable slots.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This patch changes cpqphp to use interrupt pin values just as they
come from PCI config space, i.e., 1=INTA, ..., 4=INTD.
pcibios_set_irq_routing() takes pin arguments in the range 0=INTA, ...,
3=INTD, so we'll adjust the pin just before calling it.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Clean up whitespace.
Setting 'let c_space_errors=1' in .vimrc shows all sorts of
ugliness. ;)
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
According to section 6.3.6 of the ACPI spec, the presence of an _RMV
method that evaluates to 1 is sufficient to indicate that a slot is
removable without needing an eject method. This patch refactors the
ejectable slot detection code a little in order to flag these slots as
ejectable and register them. Acpihp then binds to the expresscard slot
on my HP test machine.
Acked-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
pci_get_slot does a pci_dev_get, so pci_dev_put needs to be called in an
error case.
An alterative would be to move the test_and_set_bit before the call to
pci_get_slot.
The problem was fixed using the following semantic patch.
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@@
local idexpression *n;
statement S1,S2;
expression E,E1;
expression *ptr != NULL;
type T,T1;
@@
(
if (!(n = pci_get_slot(...))) S1
|
n = pci_get_slot(...)
)
<... when != pci_dev_put(n)
when != if (...) { <+... pci_dev_put(n) ...+> }
when != true !n || ...
when != n = (T)E
when != E = n
if (!n || ...) S2
...>
(
return \(0\|<+...n...+>\|ptr\);
|
+ pci_dev_put(n);
return ...;
|
pci_dev_put(n);
|
n = (T1)E1
|
E1 = n
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This patch is part of a larger patch series which will remove
the "char bus_id[20]" name string from struct device. The device
name is managed in the kobject anyway, and without any size
limitation, and just needlessly copied into "struct device".
To set and read the device name dev_name(dev) and dev_set_name(dev)
must be used. If your code uses static kobjects, which it shouldn't
do, "const char *init_name" can be used to statically provide the
name the registered device should have. At registration time, the
init_name field is cleared, to enforce the use of dev_name(dev) to
access the device name at a later time.
We need to get rid of all occurrences of bus_id in the entire tree
to be able to enable the new interface. Please apply this patch,
and possibly convert any remaining remaining occurrences of bus_id.
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-Off-By: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The pciehp driver waits for 1000 msec after turning power off to make
sure the power has been completely removed. But this 1000 msec wait is
not needed if a slot doesn't implement power control because software
cannot control the power. Power will be automatically removed at adapter
removal time on such a slot
Tested-by: "Phil Endecott" <phil_pibbu_endecott@chezphil.org>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
External driver files should not include any private acpica headers.
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Impact: cleanup
Now that arch/x86/pci/pci.h is used in a number of other places as well,
move the lowlevel x86 pci definitions into the architecture include files.
(not to be confused with the existing arch/x86/include/asm/pci.h file,
which provides public details about x86 PCI)
Tested on: X86_32_UP, X86_32_SMP and X86_64_SMP
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (144 commits)
powerpc/44x: Support 16K/64K base page sizes on 44x
powerpc: Force memory size to be a multiple of PAGE_SIZE
powerpc/32: Wire up the trampoline code for kdump
powerpc/32: Add the ability for a classic ppc kernel to be loaded at 32M
powerpc/32: Allow __ioremap on RAM addresses for kdump kernel
powerpc/32: Setup OF properties for kdump
powerpc/32/kdump: Implement crash_setup_regs() using ppc_save_regs()
powerpc: Prepare xmon_save_regs for use with kdump
powerpc: Remove default kexec/crash_kernel ops assignments
powerpc: Make default kexec/crash_kernel ops implicit
powerpc: Setup OF properties for ppc32 kexec
powerpc/pseries: Fix cpu hotplug
powerpc: Fix KVM build on ppc440
powerpc/cell: add QPACE as a separate Cell platform
powerpc/cell: fix build breakage with CONFIG_SPUFS disabled
powerpc/mpc5200: fix error paths in PSC UART probe function
powerpc/mpc5200: add rts/cts handling in PSC UART driver
powerpc/mpc5200: Make PSC UART driver update serial errors counters
powerpc/mpc5200: Remove obsolete code from mpc5200 MDIO driver
powerpc/mpc5200: Add MDMA/UDMA support to MPC5200 ATA driver
...
Fix trivial conflict in drivers/char/Makefile as per Paul's directions
I happened to notice that the ibmphp hotplug driver does something
rather silly in its init routine. It purposely calls module_put so as
to underflow its module ref count to avoid being removed from the
kernel. This is bad practice, and wrong, since it provides a window for
subsequent module_gets to reset the refcount to zero, allowing an unload
to race in and cause all sorts of mysterious panics. If the module is
unsafe to load, simply omitting the module_exit parameter is sufficient
to prevent the kernel from allowing the unload.
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Neil Horman <nhorman@tuxdriver.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>
This patch fixes the problem that causes an occupied slot to be turned
off even if it has a working device.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The pseries PCI hotplug code has a number of issues, ranging from
incorrect resource setup to crashes, depending on what is added,
when, whether it contains a bridge, etc etc....
This fixes a whole bunch of these, while actually simplifying the code
a bit, using more generic code in the process and factoring out common
code between adding of a PHB, a slot or a device.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Fix printk format warning:
drivers/pci/hotplug/acpiphp_ibm.c:207: warning: format '%08lx' expects type 'long unsigned int', but argument 3 has type 'long long unsigned int'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch refines messages in shpchp module. The main changes are as
follows:
- remove the trailing "."
- remove __func__ as much as possible
- capitalize the first letter of messages
- show PCI device address including its domain
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This patch refines messages in pciehp module. The main changes are as
follows:
- remove the trailing "."
- remove __func__ as much as possible
- capitalize the first letter of messages
- show PCI device address including its domain
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The following patch fixes the regression in 2.6.27 that causes kernel
NULL pointer dereference at cpqphp driver probe time. This patch should
be backported to the .27 stable series.
Seems to have been introduced by
f46753c5e3.
The root cause of this problem seems that cpqphp driver calls
pci_hp_register() wrongly. In current implementation, cpqphp driver
passes 'ctrl->pci_dev->subordinate' as a second parameter for
pci_hp_register(). But because hotplug slots and it's hotplug controller
(exists as a pci funcion) are on the same bus, it should be
'ctrl->pci_dev->bus' instead.
Cc: <stable@kernel.org>
Tested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (123 commits)
dock: make dock driver not a module
ACPI: fix ia64 build warning
ACPI: hack around sysfs warning with link order
ACPI suspend: fix build warning when CONFIG_ACPI_SLEEP=n
intel_menlo: fix build warning
panasonic-laptop: fix build
ACPICA: Update version to 20080926
ACPICA: Add support for zero-length buffer-to-string conversions
ACPICA: New: Validation for predefined ACPI methods/objects
ACPICA: Fix for implicit return compatibility
ACPICA: Fixed a couple memory leaks associated with "implicit return"
ACPICA: Optimize buffer allocation procedure
ACPICA: Fix possible memory leak, error exit path
ACPICA: Fix fault after mem allocation failure in AML parser
ACPICA: Remove unused ACPI register bit definition
ACPICA: Update version to 20080829
ACPICA: Fix possible memory leak in acpi_ns_get_external_pathname
ACPICA: Cleanup for internal Reference Object
ACPICA: Update comments - no functional changes
ACPICA: Update for Reference ACPI_OPERAND_OBJECT
...
The pattern !E && !E->fld is nonsensical. The patch below updates this
according to the assumption that && should be ||. But perhaps another
solution was intended.
The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@disable and_comm@
expression E;
identifier fld;
@@
- !E && !E->fld
+ !E || !E->fld
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This patch adds polling mechanism for Data Link Layer Link Active bit
after turning power on, instead of waiting for 1000 msec. This reduces
reduce the unnecessary long wait.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The PCI core now manages slot names on behalf of slot detection
and slot hotplug drivers, including the handling of duplicate
slot names.
We can use the fakephp driver to help test the new functionality.
Add a 'dup_slots' module param to force fakephp to create multiple
slots with the same name. We can then verify that the PCI core
correctly renamed the slots.
sapphire:/sys/bus/pci/slots # modprobe fakephp dup_slots
sapphire:/sys/bus/pci/slots # ls
fake fake-10 fake-3 fake-5 fake-7 fake-9
fake-1 fake-2 fake-4 fake-6 fake-8
Cc: kristen.c.accardi@intel.com
Cc: matthew@wil.cx
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>
Now that the PCI core manages the 'name' for each individual
hotplug driver, and all drivers (except rpaphp) have been converted
to use hotplug_slot_name(), there is no need for the PCI hotplug
core to drag around its own copy of name either.
Cc: kristen.c.accardi@intel.com
Cc: matthew@wil.cx
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>
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 shpchp's version of struct slot.
This change also removes the unused struct task_event from the
slot structure.
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>
We no longer need to manage our version of hotplug_slot->name
since the PCI and hotplug core manage it on our behalf.
Update the sn_hp_slot_private_alloc() interface to fill in
the correct name for us, as that function already has all
the parameters needed to determine the name.
Cc: kristen.c.accardi@intel.com
Cc: jpk@sgi.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>
rpaphp tends to use slot->name directly everywhere, and doesn't
ever need slot->hotplug_slot->name.
struct hotplug_slot->name is going away, so convert rpaphp directly
manipulate its own slot->name everywhere, and don't bother touching
slot->hotplug_slot->name.
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>
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 pciehp's version of struct slot, and remove
unused 'task_list' as well.
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>
We no longer need to manage our version of hotplug_slot->name
since the PCI and hotplug core manage it on our behalf.
Now, we simply advise the PCI core of the name that we would
like, and let the core take care of the rest.
Additionally, slightly rearrange the members of struct slot
so they are naturally aligned to eliminate holes.
Cc: jbarnes@virtuousgeek.org
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>
Remove 'name' from fakephp's struct dummy_slot, as the PCI core
will now manage our slot name for us.
Cc: jbarnes@virtuousgeek.org
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>
We no longer need to manage our version of hotplug_slot->name
since the PCI and hotplug core manage it on our behalf.
Now, we simply advise the PCI core of the name that we would
like, and let the core take care of the rest.
Cc: jbarnes@virtuousgeek.org
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>
We no longer need to manage our version of hotplug_slot->name
since the PCI and hotplug core manage it on our behalf.
Now, we simply advise the PCI core of the name that we would
like, and let the core take care of the rest.
Cc: kristen.c.accardi@intel.com
Cc: scottm@somanetworks.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>
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>
Prevent callers of pci_create_slot() from registering slots with
duplicate names. This condition occurs most often when PCI hotplug
drivers are loaded on platforms with broken firmware that assigns
identical names to multiple slots.
We now rename these duplicate slots on behalf of the user.
If firmware assigns the name N to multiple slots, then:
The first registered slot is assigned N
The second registered slot is assigned N-1
The third registered slot is assigned N-2
etc.
This is the permanent fix mentioned in earlier commits d6a9e9b4 and
167e782e (shpchp/pciehp: Rename duplicate slot name...).
We take advantage of the new 'hotplug' parameter in pci_create_slot()
to prevent a slot create/rename race between hotplug drivers and
detection drivers.
Scenario A:
hotplug driver detection driver
-------------- ----------------
pci_create_slot(hotplug=set)
pci_create_slot(hotplug=NULL)
The hotplug driver creates the slot with its desired name, and then
releases the semaphore. Now, the detection driver tries to create
the same slot, but it already exists. We don't care about renaming,
so return the existing slot.
Scenario B:
hotplug driver detection driver
-------------- ----------------
pci_create_slot(hotplug=NULL)
pci_create_slot(hotplug=set)
The detection driver creates the slot with name "X". Then the hotplug
driver tries to create the same slot, but wants the name "Y" instead.
We detect that we're trying to create the same slot and that we also
want a rename, so rename the slot to "Y" and return.
Scenario C:
hotplug driver hotplug driver
-------------- ----------------
pci_create_slot(hotplug=set)
pci_create_slot(hotplug=set)
Two separate hotplug drivers are attempting to claim the slot and
are passing valid hotplug_slot args to pci_create_slot(). We detect
that the slot already has a ->hotplug callback, prevent a rename,
and return -EBUSY.
Cc: kristen.c.accardi@intel.com
Cc: matthew@wil.cx
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>
Convert the pci_hotplug_slot_list_lock, which only protected the
list of hotplug slots, to a pci_hp_mutex which now protects both
interfaces.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Slot detection drivers can co-exist with hotplug drivers. The names
of the detected/claimed slots may be different depending on module
load order.
For legacy reasons, we need to allow hotplug drivers to override
the slot name if a detection driver is loaded first (and they find
the same slots).
Creating and overriding slot names should be an atomic operation,
otherwise you get a locking nightmare as various drivers race to
call pci_create_slot().
pci_create_slot() is already serialized by grabbing the pci_bus_sem.
We update the API and add a 'hotplug' param, which is:
set if the caller is a hotplug driver
NULL if the caller is a detection driver
pci_create_slot() does not actually use the 'hotplug' parameter in this
patch. A later patch will add the logic that uses it.
Cc: kristen.c.accardi@intel.com
Cc: matthew@wil.cx
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>
