When the PCI hotplug core and its first user, cpqphp, were introduced in
February 2002 with historic commit a8a2069f432c, cpqphp allocated a slot
struct for its internal use plus a hotplug_slot struct to be registered
with the hotplug core and linked the two with pointers:
https://git.kernel.org/tglx/history/c/a8a2069f432c

Nowadays, the predominant pattern in the tree is to embed ("subclass")
such structures in one another and cast to the containing struct with
container_of().  But it wasn't until July 2002 that container_of() was
introduced with historic commit ec4f214232cf:
https://git.kernel.org/tglx/history/c/ec4f214232cf

pnv_php, introduced in 2016, did the right thing and embedded struct
hotplug_slot in its internal struct pnv_php_slot, but all other drivers
cargo-culted cpqphp's design and linked separate structs with pointers.

Embedding structs is preferrable to linking them with pointers because
it requires fewer allocations, thereby reducing overhead and simplifying
error paths.  Casting an embedded struct to the containing struct
becomes a cheap subtraction rather than a dereference.  And having fewer
pointers reduces the risk of them pointing nowhere either accidentally
or due to an attack.

Convert all drivers to embed struct hotplug_slot in their internal slot
struct.  The "private" pointer in struct hotplug_slot thereby becomes
unused, so drop it.

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: Sebastian Ott <sebott@linux.ibm.com>        # drivers/pci/hotplug/s390*
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: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Corentin Chary <corentin.chary@gmail.com>
Cc: Darren Hart <dvhart@infradead.org>

Add SPDX GPL-2.0+ to all PCI files that specified the GPL and allowed
either GPL version 2 or any later version.

Remove the boilerplate GPL version 2 or later language, relying on the
assertion in b24413180f56 ("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>

The following pattern is often used:

  list_for_each_entry(dev, &bus->devices, bus_list) {
    if (pci_is_bridge(dev)) {
      ...
    }
  }

Add a for_each_pci_bridge() helper to make that code easier to write and
read by reducing indentation level.  It also saves one or few lines of code
in each occurrence.

Convert PCI core parts here at the same time.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[bhelgaas: fold in http://lkml.kernel.org/r/20171013165352.25550-1-andriy.shevchenko@linux.intel.com]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

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>

I don't have this hardware but it looks like we weren't adding bridge
devices as intended.  Maybe the bridge is always the last device?

Fixes: 05b125004815 ("PCI: cpcihp: Iterate over all devices in slot, not functions 0-7")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yijing Wang <wangyijing@huawei.com>
CC: stable@vger.kernel.org	# v3.9+

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>

* pci/hotplug:
  PCI: cpqphp: Fix possible null pointer dereference
  NVMe: Implement PCIe reset notification callback
  PCI: Notify driver before and after device reset

* pci/pci_is_bridge:
  pcmcia: Use pci_is_bridge() to simplify code
  PCI: pciehp: Use pci_is_bridge() to simplify code
  PCI: acpiphp: Use pci_is_bridge() to simplify code
  PCI: cpcihp: Use pci_is_bridge() to simplify code
  PCI: shpchp: Use pci_is_bridge() to simplify code
  PCI: rpaphp: Use pci_is_bridge() to simplify code
  sparc/PCI: Use pci_is_bridge() to simplify code
  powerpc/PCI: Use pci_is_bridge() to simplify code
  ia64/PCI: Use pci_is_bridge() to simplify code
  x86/PCI: Use pci_is_bridge() to simplify code
  PCI: Use pci_is_bridge() to simplify code
  PCI: Add new pci_is_bridge() interface
  PCI: Rename pci_is_bridge() to pci_has_subordinate()

* pci/virtualization:
  PCI: Introduce new device binding path using pci_dev.driver_override

Conflicts:
	drivers/pci/pci-sysfs.c

Use pci_is_bridge() to simplify code.  No functional change.

Requires: 326c1cdae741 PCI: Rename pci_is_bridge() to pci_has_subordinate()
Requires: 1c86438c9423 PCI: Add new pci_is_bridge() interface
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Some PCI functions used to be marked __devinit.  When CONFIG_HOTPLUG was
not set, these functions were discarded after boot.  A few callers of these
__devinit functions were marked __ref to indicate that they could safely
call the __devinit functions even though the callers were not __devinit.

But CONFIG_HOTPLUG and __devinit are now gone, and the need for the __ref
annotations is also gone, so remove them.  Relevant historical commits:

  54b956b90360 Remove __dev* markings from init.h
  a8e4b9c101ae PCI: add generic pci_hp_add_bridge()
  0ab2b57f8db8 PCI: fix section mismatch warning in pci_scan_child_bus
  451124a7cc6c PCI: fix 4x section mismatch warnings

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Multiple race conditions are possible between PCI hotplug and the generic
PCI bus rescan and device removal that can be triggered via sysfs.

To avoid those race conditions make PCI hotplug use global PCI
rescan-remove locking.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>