From 22c8ca2ac256bb681be791858b35502b5d37e73b Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Fri, 16 Nov 2012 19:39:04 -0800 Subject: [PATCH] x86, mm: Add alloc_low_pages(num) 32bit kmap mapping needs pages to be used for low to high. At this point those pages are still from pgt_buf_* from BRK, so it is ok now. But we want to move early_ioremap_page_table_range_init() out of init_memory_mapping() and only call it one time later, that will make page_table_range_init/page_table_kmap_check/alloc_low_page to use memblock to get page. memblock allocation for pages are from high to low. So will get panic from page_table_kmap_check() that has BUG_ON to do ordering checking. This patch add alloc_low_pages to make it possible to allocate serveral pages at first, and hand out pages one by one from low to high. Signed-off-by: Yinghai Lu Link: http://lkml.kernel.org/r/1353123563-3103-28-git-send-email-yinghai@kernel.org Cc: Andrew Morton Signed-off-by: H. Peter Anvin --- arch/x86/mm/init.c | 33 +++++++++++++++++++++------------ arch/x86/mm/mm_internal.h | 6 +++++- 2 files changed, 26 insertions(+), 13 deletions(-) diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index 21173fcdb4a1..02cea14c6d0c 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -25,36 +25,45 @@ unsigned long __meminitdata pgt_buf_top; static unsigned long min_pfn_mapped; -__ref void *alloc_low_page(void) +__ref void *alloc_low_pages(unsigned int num) { unsigned long pfn; - void *adr; + int i; #ifdef CONFIG_X86_64 if (after_bootmem) { - adr = (void *)get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK); + unsigned int order; - return adr; + order = get_order((unsigned long)num << PAGE_SHIFT); + return (void *)__get_free_pages(GFP_ATOMIC | __GFP_NOTRACK | + __GFP_ZERO, order); } #endif - if ((pgt_buf_end + 1) >= pgt_buf_top) { + if ((pgt_buf_end + num) >= pgt_buf_top) { unsigned long ret; if (min_pfn_mapped >= max_pfn_mapped) panic("alloc_low_page: ran out of memory"); ret = memblock_find_in_range(min_pfn_mapped << PAGE_SHIFT, max_pfn_mapped << PAGE_SHIFT, - PAGE_SIZE, PAGE_SIZE); + PAGE_SIZE * num , PAGE_SIZE); if (!ret) panic("alloc_low_page: can not alloc memory"); - memblock_reserve(ret, PAGE_SIZE); + memblock_reserve(ret, PAGE_SIZE * num); pfn = ret >> PAGE_SHIFT; - } else - pfn = pgt_buf_end++; + } else { + pfn = pgt_buf_end; + pgt_buf_end += num; + } + + for (i = 0; i < num; i++) { + void *adr; + + adr = __va((pfn + i) << PAGE_SHIFT); + clear_page(adr); + } - adr = __va(pfn * PAGE_SIZE); - clear_page(adr); - return adr; + return __va(pfn << PAGE_SHIFT); } /* need 4 4k for initial PMD_SIZE, 4k for 0-ISA_END_ADDRESS */ diff --git a/arch/x86/mm/mm_internal.h b/arch/x86/mm/mm_internal.h index b3f993a2555e..7e3b88ee078a 100644 --- a/arch/x86/mm/mm_internal.h +++ b/arch/x86/mm/mm_internal.h @@ -1,6 +1,10 @@ #ifndef __X86_MM_INTERNAL_H #define __X86_MM_INTERNAL_H -void *alloc_low_page(void); +void *alloc_low_pages(unsigned int num); +static inline void *alloc_low_page(void) +{ + return alloc_low_pages(1); +} #endif /* __X86_MM_INTERNAL_H */ -- GitLab