Commit Graph

57 Commits

Author SHA1 Message Date
Lukas Wunner 81c4b5bf30 PCI: hotplug: Constify hotplug_slot_ops
Hotplug drivers cannot declare their hotplug_slot_ops const, making them
attractive targets for attackers, because upon registration of a hotplug
slot, __pci_hp_initialize() writes to the "owner" and "mod_name" members
in that struct.

Fix by moving these members to struct hotplug_slot and constify every
driver's hotplug_slot_ops except for pciehp.

pciehp constructs its hotplug_slot_ops at runtime based on the PCIe
port's capabilities, hence cannot declare them const.  It can be
converted to __write_rarely once that's mainlined:
http://www.openwall.com/lists/kernel-hardening/2016/11/16/3

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>  # drivers/pci/hotplug/rpa*
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> # drivers/platform/x86
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: Oliver OHalloran <oliveroh@au1.ibm.com>
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>
2018-09-18 17:52:15 -05:00
Lukas Wunner 51bbf9bee3 PCI: hotplug: Demidlayer registration with the core
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>
2018-07-23 17:04:13 -05:00
Lukas Wunner 4ce6435820 PCI: hotplug: Don't leak pci_slot on registration failure
If addition of sysfs files fails on registration of a hotplug slot, the
struct pci_slot as well as the entry in the slot_list is leaked.  The
issue has been present since the hotplug core was introduced in 2002:
https://git.kernel.org/tglx/history/c/a8a2069f432c

Perhaps the idea was that even though sysfs addition fails, the slot
should still be usable.  But that's not how drivers use the interface,
they abort probe if a non-zero value is returned.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org # v2.4.15+
Cc: Greg Kroah-Hartman <greg@kroah.com>
2018-07-23 17:04:10 -05:00
Bjorn Helgaas 736759ef59 PCI: Add SPDX GPL-2.0+ to replace GPL v2 or later boilerplate
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>
2018-01-28 15:49:06 -06:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Bjorn Helgaas d9b47d5496 PCI: hotplug: Remove hotplug core message
Remove the "PCI Hot Plug PCI Core" version message.  I don't think it
contains any useful information.  Remove unused #defines and move the
author information to a comment.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2016-12-12 10:05:24 -06:00
Paul Gortmaker 57b51b9adb PCI: hotplug: Make core explicitly non-modular
This code is not being built as a module by anyone:

  obj-$(CONFIG_HOTPLUG_PCI)           += pci_hotplug.o
  [...]
  pci_hotplug-objs                    := pci_hotplug_core.o

  drivers/pci/hotplug/Kconfig:menuconfig HOTPLUG_PCI
  drivers/pci/hotplug/Kconfig:  bool "Support for PCI Hotplug"

Remove uses of MODULE_DESCRIPTION(), MODULE_AUTHOR(), MODULE_LICENSE(),
etc., so that when reading the driver there is no doubt it is builtin-only.
The information is preserved in comments at the top of the file.

Remove orphaned exit function in cpci_hotplug_core.c.

Note that for non-modular code, module_init() translates to
device_initcall().  One could argue that we should use subsys_initcall()
here, but for now we stick with runtime equivalence.

We would delete module.h and just keep the moduleparam.h include (since the
file does use module_param), but there is a try_module_get and module_put
pairing that prevents us from doing that.

[bhelgaas: changelog]
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Scott Murray <scott@spiteful.org>
CC: Kristen Carlson Accardi <kristen@linux.intel.com>
2016-08-24 17:20:14 -05:00
Bjorn Helgaas 9662e32c81 Merge branch 'pci/trivial' into next
* pci/trivial:
  PCI: shpchp: Constify hpc_ops structure
  PCI: Use kobj_to_dev() instead of open-coding it
  PCI: Use to_pci_dev() instead of open-coding it
  PCI: Fix all whitespace issues
  PCI/MSI: Fix typos in <linux/msi.h>
2016-01-20 11:48:25 -06:00
Geliang Tang 2ac83cccab PCI: hotplug: Use list_for_each_entry() to simplify code
Use list_for_each_entry() instead of list_for_each() to simplify the code.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2016-01-10 16:10:29 -06:00
Bogicevic Sasa ff3ce480e8 PCI: Fix all whitespace issues
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>
2016-01-08 10:35:24 -06:00
Yijing Wang a6ed1f4e94 PCI: Use "slot" and "pci_slot" for struct hotplug_slot and struct pci_slot
Now in pci_hotplug_core.c, we randomly name a struct hotplug_slot and a
struct pci_slot.  It's easy to confuse them, so let us use "slot" for a
struct hotplug_slot and "pci_slot" for a struct pci_slot.

No functional change.

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-07-15 22:03:31 -05:00
Ryan Desfosses 227f064705 PCI: Merge multi-line quoted strings
Merge quoted strings that are broken across lines into a single entity.
The compiler merges them anyway, but checkpatch complains about it, and
merging them makes it easier to grep for strings.

No functional change.

[bhelgaas: changelog, do the same for everything under drivers/pci]
Signed-off-by: Ryan Desfosses <ryan@desfo.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-06-10 20:20:42 -06:00
Ryan Desfosses 3c78bc61f5 PCI: Whitespace cleanup
Fix various whitespace errors.

No functional change.

[bhelgaas: fix other similar problems]
Signed-off-by: Ryan Desfosses <ryan@desfo.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-06-10 20:20:19 -06:00
Ryan Desfosses b7fe943421 PCI: Move EXPORT_SYMBOL so it immediately follows function/variable
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>
2014-06-10 13:36:10 -06:00
Bjorn Helgaas f7625980f5 PCI: Fix whitespace, capitalization, and spelling errors
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>
2013-11-14 11:28:18 -07:00
Bjorn Helgaas d67aed63b8 PCI: Remove __must_check from definitions
The __must_check (gcc "warn_unused_result") attribute only makes sense
when compiling the *caller* of the function, so the attribute should
appear on the declaration in the header file, not on the definition.

The declarations of these functions are already annotated with
__must_check.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-04-17 10:20:58 -06:00
Bjorn Helgaas b638d7e7b8 PCI: Remove unused variables
This fixes "set but not used" warnings found via "make W=1".

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-04-15 10:56:27 -06:00
Bjorn Helgaas c3139ba212 PCI: Move cpci_hotplug_init() proto to header file
cpci_hotplug_init() and cpci_hotplug_exit() are defined in
cpci_hotplug_core.c but had extern declarations in pci_hotplug_core.c.
This puts the declarations in a header file included both places so
the compiler can help keep everything consistent.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-04-15 10:44:18 -06:00
Rusty Russell 90ab5ee941 module_param: make bool parameters really bool (drivers & misc)
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>
2012-01-13 09:32:20 +10:30
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Matthew Wilcox 3749c51ac6 PCI: Make current and maximum bus speeds part of the PCI core
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>
2010-02-22 16:15:17 -08:00
Stefan Assmann 17d6715279 PCI hotplug: change PCI nomenclature
Change PCI nomenclature according to
http://www.pcisig.com/developers/procedures/logos/Trademark_and_Logo_Usage_Guidelines_updated_112206.pdf.

Signed-off-by: Stefan Assmann <sassmann@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-11-04 08:47:13 -08:00
Kenji Kaneshige 825c423a35 PCI hotplug: add support for 5.0G link speed
Add support for PCI-E 5.0 GT/s in max_bus_speed and cur_bus_speed.

Reviewed-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-09 13:29:50 -07:00
Kenji Kaneshige 6ed6a8dc83 PCI hotplug: fix typo in pcie link speed info
Fix typo in PCI-E link speed.

Reviewed-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-09 13:29:49 -07:00
Randy Dunlap 503998ca4a PCI: fix kernel-doc warnings
Add documentation for missing parameters in PCI hotplug code.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-29 12:13:56 -07:00
Kenji Kaneshige c825bc94c8 PCI hotplug: create symlink to hotplug driver module
Create symbolic link to hotplug driver module in the PCI slot
directory (/sys/bus/pci/slots/<SLOT#>). In the past, we need to load
hotplug drivers one by one to identify the hotplug driver that handles
the slot, and it was very inconvenient especially for trouble shooting.
With this change, we can easily identify the hotplug driver.

Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
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>
2009-06-16 14:30:11 -07:00
Kenji Kaneshige 498a8faf2c PCI hotplug: fix return value of has_foo() functions
Current has_foo() functions in pci_hotplug_core.c returns 0 if the
"foo" property is true. It would cause misunderstanding. In addition,
the error code of those functions is never checked, so this patch
changes those functions' error code to 'bool' and return true if the
property "foo" is true.

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>
2009-06-16 14:30:11 -07:00
Alex Chiang 58319b802a PCI: Hotplug core: remove 'name'
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>
2008-10-22 16:42:43 -07:00
Alex Chiang 5fe6cc6068 PCI: prevent duplicate slot names
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>
2008-10-22 16:42:39 -07:00
Kenji Kaneshige 95cb909396 PCI Hotplug: serialize pci_hp_register and pci_hp_deregister
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>
2008-10-22 16:42:38 -07:00
Alex Chiang 828f37683e PCI: update pci_create_slot() to take a 'hotplug' param
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>
2008-10-22 16:42:38 -07:00
Alex Chiang 1359f2701b PCI Hotplug core: add 'name' param pci_hp_register interface
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>
2008-10-22 16:42:37 -07:00
Kenji Kaneshige bd1d9855be PCI hotplug: fix get_##name return value problem
The commit 356a9d6f3dd283f83861adf1ac909879f0e66411 (PCI: fix hotplug
get_##name return value problem) doesn't seem to be merged properly.
Because of this, PCI hotplug no longer works (Read/Write PCI hotplug
files always returns -ENODEV).

This patch fixes wrong check of try_module_get() return value check in
get_##name().

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-10-20 11:01:50 -07:00
Zhao, Yu c8761fe80e PCI: fix hotplug get_##name return value problem
Currently, get_##name in pci_hotplug_core.c will return 0 if module
unload wins the race between unload & reading the hotplug file.  Fix
that case to return -ENODEV like it should.

Reviewed-by: Alex Chiang <achiang@hp.com>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-10-20 10:54:25 -07:00
Kenji Kaneshige b86ec7ed28 Remove unnecessary 'tmp' variable from pci_hp_register().
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-06-25 15:58:39 -07:00
Jesse Barnes 65b943f630 PCI: fixup kdoc blocks for hotplug functions
A few warnings snuck in as parameters were added or renamed.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-06-25 15:27:34 -07:00
Alex Chiang 8344b568f5 PCI: ACPI PCI slot detection driver
Detect all physical PCI slots as described by ACPI, and create entries in
/sys/bus/pci/slots/.

Not all physical slots are hotpluggable, and the acpiphp module does not
detect them.  Now we know the physical PCI geography of our system, without
caring about hotplug.

[kaneshige.kenji@jp.fujitsu.com: export-kobject_rename-for-pci_hotplug_core]
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Acked-by: Greg KH <greg@kroah.com>
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix build with CONFIG_DMI=n]
Signed-off-by: Alex Chiang <achiang@hp.com>
Cc: Greg KH <greg@kroah.com>
Cc: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Cc: Len Brown <lenb@kernel.org>
Acked-by: Len Brown <len.brown@intel.com>
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-06-10 14:37:14 -07:00
Alex Chiang f46753c5e3 PCI: introduce pci_slot
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>
2008-06-10 14:37:03 -07:00
Kenji Kaneshige a86161b313 pci hotplug core: add check of duplicate slot name
Fix the following errors reported by Jan C. Nordholz in
http://bugzilla.kernel.org/show_bug.cgi?id=10751.

kobject_add_internal failed for 2 with -EEXIST, don't try to register things with the same name in the same directory.
Pid: 1, comm: swapper Tainted: G        W 2.6.26-rc3 #1
 [<c0266980>] kobject_add_internal+0x140/0x190
 [<c0266afd>] kobject_init_and_add+0x2d/0x40
 [<c027bc91>] pci_hp_register+0x81/0x2f0
 [<c027fd07>] pciehp_probe+0x1a7/0x470
 [<c01b3b84>] sysfs_add_one+0x44/0xa0
 [<c01b3c1f>] sysfs_addrm_start+0x3f/0xb0
 [<c01b497a>] sysfs_create_link+0x8a/0xf0
 [<c0279570>] pcie_port_probe_service+0x50/0x80
 [<c02e0545>] driver_sysfs_add+0x55/0x70
 [<c02e0662>] driver_probe_device+0x82/0x180
 [<c02e07cc>] __driver_attach+0x6c/0x70
 [<c02dfe0a>] bus_for_each_dev+0x3a/0x60
 [<c05db2d0>] pcied_init+0x0/0x80
 [<c02e04e6>] driver_attach+0x16/0x20
 [<c02e0760>] __driver_attach+0x0/0x70
 [<c02e0341>] bus_add_driver+0x1a1/0x220
 [<c05db2d0>] pcied_init+0x0/0x80
 [<c02e09cd>] driver_register+0x4d/0x120
 [<c05db050>] ibm_acpiphp_init+0x0/0x190
 [<c0125aab>] printk+0x1b/0x20
 [<c05db2d0>] pcied_init+0x0/0x80
 [<c05db2de>] pcied_init+0xe/0x80
 [<c05c751a>] kernel_init+0x10a/0x300
 [<c0120138>] schedule_tail+0x18/0x50
 [<c0103b9a>] ret_from_fork+0x6/0x1c
 [<c05c7410>] kernel_init+0x0/0x300
 [<c05c7410>] kernel_init+0x0/0x300
 [<c010485b>] kernel_thread_helper+0x7/0x1c
 =======================
pci_hotplug: Unable to register kobject '2'<3>pciehp: pci_hp_register failed with error -22

Slot with the same name can be registered multiple times if shpchp or
pciehp driver is loaded after acpiphp is loaded because ACPI based
hotplug driver and Native OS hotplug driver trying to handle the same
physical slot. In this case, current pci_hotplug core will call
kobject_init_and_add() muliple time with the same name. This is the
cause of this problem. To fix this problem, this patch adds the check
into pci_hp_register() to see if the slot with the same name.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-05-27 15:43:40 -07:00
Harvey Harrison 66bef8c059 PCI: replace remaining __FUNCTION__ occurrences
__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-20 21:47:09 -07:00
Joe Perches a6f29a98af PCI: Add missing "space" in printk messages
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-01 15:04:22 -08:00
Alex Chiang 41ece3829f PCI: hotplug: pci_hotplug_core whitespace fix
Remove superfluous space.

Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-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>
2008-02-01 15:04:20 -08:00
Greg Kroah-Hartman c10997f657 Kobject: convert drivers/* from kobject_unregister() to kobject_put()
There is no need for kobject_unregister() anymore, thanks to Kay's
kobject cleanup changes, so replace all instances of it with
kobject_put().


Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:40 -08:00
Greg Kroah-Hartman 0fed80f7a6 driver core: add way to get to bus kset
This allows an easier way to get to the kset associated with a struct
bus_type (you have three to choose from...)  This will make it easier to
move these fields to be dynamic in a future patch.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:33 -08:00
Greg Kroah-Hartman 64dbcac3a1 Kobject: change drivers/pci/hotplug/pci_hotplug_core.c to use kobject_init_and_add
Stop using kobject_register, as this way we can control the sending of
the uevent properly, after everything is properly initialized.

Cc: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:28 -08:00
Greg Kroah-Hartman 81ace5cd8f kset: convert pci hotplug to use kset_create_and_add
This also renames pci_hotplug_slots_subsys to pcis_hotplug_slots_kset
catch all current users with a build error instead of a build warning
which can easily be missed.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:14 -08:00
Greg Kroah-Hartman 3514faca19 kobject: remove struct kobj_type from struct kset
We don't need a "default" ktype for a kset.  We should set this
explicitly every time for each kset.  This change is needed so that we
can make ksets dynamic, and cleans up one of the odd, undocumented
assumption that the kset/kobject/ktype model has.

This patch is based on a lot of help from Kay Sievers.

Nasty bug in the block code was found by Dave Young
<hidave.darkstar@gmail.com>

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:10 -08:00
Linus Torvalds 4271e0f7e1 Get rid of unused variable warning in drivers/pci/hotplug/pci_hotplug_core.c
Commit 5a7ad7f044 removed all uses of
'retval', but didn't remove the variable itself.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-15 09:07:58 -07:00
Tejun Heo 5a7ad7f044 sysfs: kill sysfs_update_file()
sysfs_update_file() depends on inode->i_mtime but sysfs iondes are now
reclaimable making the reported modification time unreliable.  There's
only one user (pci hotplug) of this notification mechanism and it
reportedly isn't utilized from userland.

Kill sysfs_update_file().

Signed-off-by: Tejun Heo <htejun@gmail.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-12 14:51:09 -07:00
Randy Dunlap e63340ae6b header cleaning: don't include smp_lock.h when not used
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>
2007-05-08 11:15:07 -07:00