diff options
author | Tang Chen <tangchen@cn.fujitsu.com> | 2013-11-12 15:08:02 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-11-13 12:09:08 +0900 |
commit | 0167d7d8b0beb4cf12076b47e4dc73897ae5acb0 (patch) | |
tree | c7430b0ad44e46fdb1537e1605d85d9e38028095 /arch/x86/mm/init.c | |
parent | 79442ed189acb8b949662676e750eda173c06f9b (diff) | |
download | linux-0167d7d8b0beb4cf12076b47e4dc73897ae5acb0.tar.bz2 |
x86/mm: factor out of top-down direct mapping setup
Create a new function memory_map_top_down to factor out of the top-down
direct memory mapping pagetable setup. This is also a preparation for the
following patch, which will introduce the bottom-up memory mapping. That
said, we will put the two ways of pagetable setup into separate functions,
and choose to use which way in init_mem_mapping, which makes the code more
clear.
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Thomas Renninger <trenn@suse.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/x86/mm/init.c')
-rw-r--r-- | arch/x86/mm/init.c | 59 |
1 files changed, 39 insertions, 20 deletions
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index ce32017c5e38..742d6d4ad9eb 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -418,27 +418,27 @@ static unsigned long __init get_new_step_size(unsigned long step_size) return step_size << 5; } -void __init init_mem_mapping(void) +/** + * memory_map_top_down - Map [map_start, map_end) top down + * @map_start: start address of the target memory range + * @map_end: end address of the target memory range + * + * This function will setup direct mapping for memory range + * [map_start, map_end) in top-down. That said, the page tables + * will be allocated at the end of the memory, and we map the + * memory in top-down. + */ +static void __init memory_map_top_down(unsigned long map_start, + unsigned long map_end) { - unsigned long end, real_end, start, last_start; + unsigned long real_end, start, last_start; unsigned long step_size; unsigned long addr; unsigned long mapped_ram_size = 0; unsigned long new_mapped_ram_size; - probe_page_size_mask(); - -#ifdef CONFIG_X86_64 - end = max_pfn << PAGE_SHIFT; -#else - end = max_low_pfn << PAGE_SHIFT; -#endif - - /* the ISA range is always mapped regardless of memory holes */ - init_memory_mapping(0, ISA_END_ADDRESS); - /* xen has big range in reserved near end of ram, skip it at first.*/ - addr = memblock_find_in_range(ISA_END_ADDRESS, end, PMD_SIZE, PMD_SIZE); + addr = memblock_find_in_range(map_start, map_end, PMD_SIZE, PMD_SIZE); real_end = addr + PMD_SIZE; /* step_size need to be small so pgt_buf from BRK could cover it */ @@ -453,13 +453,13 @@ void __init init_mem_mapping(void) * end of RAM in [min_pfn_mapped, max_pfn_mapped) used as new pages * for page table. */ - while (last_start > ISA_END_ADDRESS) { + while (last_start > map_start) { if (last_start > step_size) { start = round_down(last_start - 1, step_size); - if (start < ISA_END_ADDRESS) - start = ISA_END_ADDRESS; + if (start < map_start) + start = map_start; } else - start = ISA_END_ADDRESS; + start = map_start; new_mapped_ram_size = init_range_memory_mapping(start, last_start); last_start = start; @@ -470,8 +470,27 @@ void __init init_mem_mapping(void) mapped_ram_size += new_mapped_ram_size; } - if (real_end < end) - init_range_memory_mapping(real_end, end); + if (real_end < map_end) + init_range_memory_mapping(real_end, map_end); +} + +void __init init_mem_mapping(void) +{ + unsigned long end; + + probe_page_size_mask(); + +#ifdef CONFIG_X86_64 + end = max_pfn << PAGE_SHIFT; +#else + end = max_low_pfn << PAGE_SHIFT; +#endif + + /* the ISA range is always mapped regardless of memory holes */ + init_memory_mapping(0, ISA_END_ADDRESS); + + /* setup direct mapping for range [ISA_END_ADDRESS, end) in top-down*/ + memory_map_top_down(ISA_END_ADDRESS, end); #ifdef CONFIG_X86_64 if (max_pfn > max_low_pfn) { |