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 post (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.): v4: https://lkml.kernel.org/r/20180507063224.24229-1-bhe@xxxxxxxxxx https://lkml.org/lkml/2018/5/7/36 v3: https://lkml.kernel.org/r/20180419001848.3041-1-bhe@xxxxxxxxxx https://lkml.org/lkml/2018/4/18/767 v2: https://lkml.kernel.org/r/20180408024724.16812-1-bhe@xxxxxxxxxx https://lkml.org/lkml/2018/4/7/169 v1: https://lkml.kernel.org/r/20180322033722.9279-1-bhe@xxxxxxxxxx https://lkml.org/lkml/2018/3/21/952 Changelog: v4->v5: Add new patch 0001 to move duplicated reparent_resources() to kernel/resource.c to make it be shared by different ARCH-es. Fix several code bugs reported by test robot on ARCH powerpc and microblaze. 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 (4): resource: Move reparent_resources() to kernel/resource.c and make it public 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/arm/plat-samsung/pm-check.c | 6 +- arch/microblaze/pci/pci-common.c | 41 +---- arch/powerpc/kernel/pci-common.c | 39 +---- 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/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 | 21 ++- kernel/kexec_file.c | 2 + kernel/resource.c | 259 ++++++++++++++++++---------- 20 files changed, 244 insertions(+), 227 deletions(-) -- 2.13.6
