Messages in this thread Patch in this message | | | From | Pekka Enberg <> | Subject | [PATCH 1/3] x86/mm: Simplify memory mapping PFN calculation | Date | Sat, 14 Jul 2012 16:41:05 +0300 |
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Introduce two new helper functions, addr_to_pmd_pfn() and addr_to_pud_pfn(), to simplify init_memory_mapping() code flow.
Cc: Tejun Heo <tj@kernel.org> Cc: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Pekka Enberg <penberg@kernel.org> --- arch/x86/mm/init.c | 38 +++++++++++++++++++++----------------- 1 files changed, 21 insertions(+), 17 deletions(-)
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index bc4e9d8..9eb53c2 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -117,6 +117,16 @@ static int __meminit save_mr(struct map_range *mr, int nr_range, return nr_range; } +static unsigned long addr_to_pmd_pfn(unsigned long addr) +{ + return (addr >> PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT); +} + +static unsigned long addr_to_pud_pfn(unsigned long addr) +{ + return (addr >> PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT); +} + /* * Setup the direct mapping of the physical memory at PAGE_OFFSET. * This runs before bootmem is initialized and gets pages directly from @@ -180,11 +190,9 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, if (pos == 0) end_pfn = 1<<(PMD_SHIFT - PAGE_SHIFT); else - end_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT) - << (PMD_SHIFT - PAGE_SHIFT); + end_pfn = addr_to_pmd_pfn(pos + (PMD_SIZE - 1)); #else /* CONFIG_X86_64 */ - end_pfn = ((pos + (PMD_SIZE - 1)) >> PMD_SHIFT) - << (PMD_SHIFT - PAGE_SHIFT); + end_pfn = addr_to_pmd_pfn(pos + (PMD_SIZE - 1)); #endif if (end_pfn > (end >> PAGE_SHIFT)) end_pfn = end >> PAGE_SHIFT; @@ -194,15 +202,13 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, } /* big page (2M) range */ - start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT) - << (PMD_SHIFT - PAGE_SHIFT); + start_pfn = addr_to_pmd_pfn(pos + (PMD_SIZE - 1)); #ifdef CONFIG_X86_32 - end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT); + end_pfn = addr_to_pmd_pfn(end); #else /* CONFIG_X86_64 */ - end_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT) - << (PUD_SHIFT - PAGE_SHIFT); - if (end_pfn > ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT))) - end_pfn = ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT)); + end_pfn = addr_to_pud_pfn(pos + (PUD_SIZE - 1)); + if (end_pfn > addr_to_pmd_pfn(end)) + end_pfn = addr_to_pmd_pfn(end); #endif if (start_pfn < end_pfn) { @@ -213,9 +219,8 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, #ifdef CONFIG_X86_64 /* big page (1G) range */ - start_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT) - << (PUD_SHIFT - PAGE_SHIFT); - end_pfn = (end >> PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT); + start_pfn = addr_to_pud_pfn(pos + (PUD_SIZE - 1)); + end_pfn = addr_to_pud_pfn(end); if (start_pfn < end_pfn) { nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, page_size_mask & @@ -224,9 +229,8 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, } /* tail is not big page (1G) alignment */ - start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT) - << (PMD_SHIFT - PAGE_SHIFT); - end_pfn = (end >> PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT); + start_pfn = addr_to_pmd_pfn(pos + (PMD_SIZE - 1)); + end_pfn = addr_to_pmd_pfn(end); if (start_pfn < end_pfn) { nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, page_size_mask & (1<<PG_LEVEL_2M)); -- 1.7.7.6
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