[PATCH v4 0/3] resource: Use list_head to link sibling resource

[Baoquan He <bhe-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>]

This patchset is doing:
1) Replace struct resource's sibling list from singly linked list to
list_head. Clearing out those pointer operation within singly linked
list for better code readability.
2) Based on list_head replacement, add a new function
walk_system_ram_res_rev() which can does reversed iteration on
iomem_resource's siblings.
3) Change kexec_file loading to search system RAM top down for kernel
loadin, using walk_system_ram_res_rev().

Note:
This patchset passed testing on my kvm guest, x86_64 arch with network
enabling. The thing we need pay attetion to is that a root resource's
child member need be initialized specifically with LIST_HEAD_INIT() if
statically defined or INIT_LIST_HEAD() for dynamically definition. Here
Just like we do for iomem_resource/ioport_resource, or the change in
get_pci_domain_busn_res().


Links of the old posting(Boris pointed out that we should use
https://lkml.kernel.org/r/Message-ID, while it can't be opened from
my side, so paste all of them here.):
v3:
https://lkml.kernel.org/r/20180419001848.3041-1-bhe-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org
https://lkml.org/lkml/2018/4/18/767

v2:
https://lkml.kernel.org/r/20180408024724.16812-1-bhe-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org
https://lkml.org/lkml/2018/4/7/169

v1:
https://lkml.kernel.org/r/20180322033722.9279-1-bhe-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org
https://lkml.org/lkml/2018/3/21/952

Changelog:
v3->v4:
  Fix several bugs test robot reported. Rewrite cover letter and patch
  log according to reviewer's comment.

v2->v3:
  Rename resource functions first_child() and sibling() to
  resource_first_chils() and resource_sibling(). Dan suggested this.

  Move resource_first_chils() and resource_sibling() to linux/ioport.h
  and make them as inline function. Rob suggested this. Accordingly add
  linux/list.h including in linux/ioport.h, please help review if this
  bring efficiency degradation or code redundancy.

  The change on struct resource {} bring two pointers of size increase,
  mention this in git log to make it more specifically, Rob suggested
  this.

v1->v2:
  Use list_head instead to link resource siblings. This is suggested by
  Andrew.

  Rewrite walk_system_ram_res_rev() after list_head is taken to link
  resouce siblings.

Baoquan He (3):
  resource: Use list_head to link sibling resource
  resource: add walk_system_ram_res_rev()
  kexec_file: Load kernel at top of system RAM if required

 arch/microblaze/pci/pci-common.c            |  31 ++--
 arch/sparc/kernel/ioport.c                  |   2 +-
 arch/xtensa/include/asm/pci-bridge.h        |   4 +-
 drivers/eisa/eisa-bus.c                     |   2 +
 drivers/gpu/drm/drm_memory.c                |   3 +-
 drivers/gpu/drm/gma500/gtt.c                |   5 +-
 drivers/hv/vmbus_drv.c                      |  52 +++----
 drivers/input/joystick/iforce/iforce-main.c |   4 +-
 drivers/nvdimm/e820.c                       |   2 +-
 drivers/nvdimm/namespace_devs.c             |   6 +-
 drivers/nvdimm/nd.h                         |   5 +-
 drivers/of/address.c                        |   4 +-
 drivers/parisc/lba_pci.c                    |   4 +-
 drivers/pci/host/vmd.c                      |   8 +-
 drivers/pci/probe.c                         |   2 +
 drivers/pci/setup-bus.c                     |   2 +-
 include/linux/ioport.h                      |  20 ++-
 kernel/kexec_file.c                         |   2 +
 kernel/resource.c                           | 221 ++++++++++++++++------------
 19 files changed, 215 insertions(+), 164 deletions(-)

-- 
2.13.6