From 4c546b8a34690ca858e50f2017b8bb6e358365d1 Mon Sep 17 00:00:00 2001 From: AKASHI Takahiro Date: Mon, 3 Apr 2017 11:23:54 +0900 Subject: [PATCH] memblock: add memblock_clear_nomap() This function, with a combination of memblock_mark_nomap(), will be used in a later kdump patch for arm64 when it temporarily isolates some range of memory from the other memory blocks in order to create a specific kernel mapping at boot time. Signed-off-by: AKASHI Takahiro Reviewed-by: Ard Biesheuvel Signed-off-by: Catalin Marinas --- include/linux/memblock.h | 1 + mm/memblock.c | 12 ++++++++++++ 2 files changed, 13 insertions(+) diff --git a/include/linux/memblock.h b/include/linux/memblock.h index bdfc65af4152..e82daffcfc44 100644 --- a/include/linux/memblock.h +++ b/include/linux/memblock.h @@ -93,6 +93,7 @@ int memblock_mark_hotplug(phys_addr_t base, phys_addr_t size); int memblock_clear_hotplug(phys_addr_t base, phys_addr_t size); int memblock_mark_mirror(phys_addr_t base, phys_addr_t size); int memblock_mark_nomap(phys_addr_t base, phys_addr_t size); +int memblock_clear_nomap(phys_addr_t base, phys_addr_t size); ulong choose_memblock_flags(void); /* Low level functions */ diff --git a/mm/memblock.c b/mm/memblock.c index 696f06d17c4e..2f4ca8104ea4 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -804,6 +804,18 @@ int __init_memblock memblock_mark_nomap(phys_addr_t base, phys_addr_t size) return memblock_setclr_flag(base, size, 1, MEMBLOCK_NOMAP); } +/** + * memblock_clear_nomap - Clear flag MEMBLOCK_NOMAP for a specified region. + * @base: the base phys addr of the region + * @size: the size of the region + * + * Return 0 on success, -errno on failure. + */ +int __init_memblock memblock_clear_nomap(phys_addr_t base, phys_addr_t size) +{ + return memblock_setclr_flag(base, size, 0, MEMBLOCK_NOMAP); +} + /** * __next_reserved_mem_region - next function for for_each_reserved_region() * @idx: pointer to u64 loop variable