diff options
author | Yinghai Lu <yinghai@kernel.org> | 2012-11-16 19:38:58 -0800 |
---|---|---|
committer | H. Peter Anvin <hpa@linux.intel.com> | 2012-11-17 11:59:19 -0800 |
commit | 8d57470d8f859635deffe3919d7d4867b488b85a (patch) | |
tree | 8576bb911f3f671952a6d2310b787e1ed55e4456 /arch/x86/kernel | |
parent | f763ad1d3870abb811ec7520b4c1adc56471a3a4 (diff) |
x86, mm: setup page table in top-down
Get pgt_buf early from BRK, and use it to map PMD_SIZE from top at first.
Then use mapped pages to map more ranges below, and keep looping until
all pages get mapped.
alloc_low_page will use page from BRK at first, after that buffer is used
up, will use memblock to find and reserve pages for page table usage.
Introduce min_pfn_mapped to make sure find new pages from mapped ranges,
that will be updated when lower pages get mapped.
Also add step_size to make sure that don't try to map too big range with
limited mapped pages initially, and increase the step_size when we have
more mapped pages on hand.
We don't need to call pagetable_reserve anymore, reserve work is done
in alloc_low_page() directly.
At last we can get rid of calculation and find early pgt related code.
-v2: update to after fix_xen change,
also use MACRO for initial pgt_buf size and add comments with it.
-v3: skip big reserved range in memblock.reserved near end.
-v4: don't need fix_xen change now.
-v5: add changelog about moving about reserving pagetable to alloc_low_page.
Suggested-by: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1353123563-3103-22-git-send-email-yinghai@kernel.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r-- | arch/x86/kernel/setup.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 94f922a73c54..f7634092931b 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -124,6 +124,7 @@ */ unsigned long max_low_pfn_mapped; unsigned long max_pfn_mapped; +unsigned long min_pfn_mapped; #ifdef CONFIG_DMI RESERVE_BRK(dmi_alloc, 65536); @@ -900,6 +901,8 @@ void __init setup_arch(char **cmdline_p) reserve_ibft_region(); + early_alloc_pgt_buf(); + /* * Need to conclude brk, before memblock_x86_fill() * it could use memblock_find_in_range, could overlap with |