The memblock_cap_memory_range() removes all the memory except the range passed to it. Extend this function to receive memblock_type with the regions that should be kept. Enable this function in arm64 for reservation of multiple regions for the crash kernel. Signed-off-by: Chen Zhou <chenzhou10@xxxxxxxxxx> Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx> --- include/linux/memblock.h | 1 + mm/memblock.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 46 insertions(+) diff --git a/include/linux/memblock.h b/include/linux/memblock.h index 47e3c06..180877c 100644 --- a/include/linux/memblock.h +++ b/include/linux/memblock.h @@ -446,6 +446,7 @@ phys_addr_t memblock_start_of_DRAM(void); phys_addr_t memblock_end_of_DRAM(void); void memblock_enforce_memory_limit(phys_addr_t memory_limit); void memblock_cap_memory_range(phys_addr_t base, phys_addr_t size); +void memblock_cap_memory_ranges(struct memblock_type *regions_to_keep); void memblock_mem_limit_remove_map(phys_addr_t limit); bool memblock_is_memory(phys_addr_t addr); bool memblock_is_map_memory(phys_addr_t addr); diff --git a/mm/memblock.c b/mm/memblock.c index f315eca..9661807 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -1697,6 +1697,51 @@ void __init memblock_cap_memory_range(phys_addr_t base, phys_addr_t size) base + size, PHYS_ADDR_MAX); } +void __init memblock_cap_memory_ranges(struct memblock_type *regions_to_keep) +{ + int start_rgn[INIT_MEMBLOCK_REGIONS], end_rgn[INIT_MEMBLOCK_REGIONS]; + int i, j, ret, nr = 0; + struct memblock_region *regs = regions_to_keep->regions; + + for (i = 0; i < regions_to_keep->cnt; i++) { + ret = memblock_isolate_range(&memblock.memory, regs[i].base, + regs[i].size, &start_rgn[i], &end_rgn[i]); + if (ret) + break; + nr++; + } + if (!nr) + return; + + /* remove all the MAP regions */ + for (i = memblock.memory.cnt - 1; i >= end_rgn[nr - 1]; i--) + if (!memblock_is_nomap(&memblock.memory.regions[i])) + memblock_remove_region(&memblock.memory, i); + + for (i = nr - 1; i > 0; i--) + for (j = start_rgn[i] - 1; j >= end_rgn[i - 1]; j--) + if (!memblock_is_nomap(&memblock.memory.regions[j])) + memblock_remove_region(&memblock.memory, j); + + for (i = start_rgn[0] - 1; i >= 0; i--) + if (!memblock_is_nomap(&memblock.memory.regions[i])) + memblock_remove_region(&memblock.memory, i); + + /* truncate the reserved regions */ + memblock_remove_range(&memblock.reserved, 0, regs[0].base); + + for (i = nr - 1; i > 0; i--) { + phys_addr_t remove_base = regs[i - 1].base + regs[i - 1].size; + phys_addr_t remove_size = regs[i].base - remove_base; + + memblock_remove_range(&memblock.reserved, remove_base, + remove_size); + } + + memblock_remove_range(&memblock.reserved, + regs[nr - 1].base + regs[nr - 1].size, PHYS_ADDR_MAX); +} + void __init memblock_mem_limit_remove_map(phys_addr_t limit) { phys_addr_t max_addr; -- 2.7.4 _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec