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 <takahiro.akashi@linaro.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
AKASHI Takahiro 2017-04-03 11:23:54 +09:00 committed by Catalin Marinas
parent dffb0113d5
commit 4c546b8a34
2 changed files with 13 additions and 0 deletions

View File

@ -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 */

View File

@ -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