diff options
| -rw-r--r-- | arch/s390/include/asm/pgtable.h | 22 | ||||
| -rw-r--r-- | arch/s390/mm/init.c | 49 |
2 files changed, 64 insertions, 7 deletions
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 3157441ee1d..22a29457100 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -46,11 +46,27 @@ extern void vmem_map_init(void); #define update_mmu_cache(vma, address, ptep) do { } while (0) /* - * ZERO_PAGE is a global shared page that is always zero: used + * ZERO_PAGE is a global shared page that is always zero; used * for zero-mapped memory areas etc.. */ -extern char empty_zero_page[PAGE_SIZE]; -#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page)) + +extern unsigned long empty_zero_page; +extern unsigned long zero_page_mask; + +#define ZERO_PAGE(vaddr) \ + (virt_to_page((void *)(empty_zero_page + \ + (((unsigned long)(vaddr)) &zero_page_mask)))) + +#define is_zero_pfn is_zero_pfn +static inline int is_zero_pfn(unsigned long pfn) +{ + extern unsigned long zero_pfn; + unsigned long offset_from_zero_pfn = pfn - zero_pfn; + return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT); +} + +#define my_zero_pfn(addr) page_to_pfn(ZERO_PAGE(addr)) + #endif /* !__ASSEMBLY__ */ /* diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index 94b8ba2ec85..0744fb3536b 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -42,9 +42,52 @@ DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE))); -char empty_zero_page[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE))); +unsigned long empty_zero_page, zero_page_mask; EXPORT_SYMBOL(empty_zero_page); +static unsigned long setup_zero_pages(void) +{ + struct cpuid cpu_id; + unsigned int order; + unsigned long size; + struct page *page; + int i; + + get_cpu_id(&cpu_id); + switch (cpu_id.machine) { + case 0x9672: /* g5 */ + case 0x2064: /* z900 */ + case 0x2066: /* z900 */ + case 0x2084: /* z990 */ + case 0x2086: /* z990 */ + case 0x2094: /* z9-109 */ + case 0x2096: /* z9-109 */ + order = 0; + break; + case 0x2097: /* z10 */ + case 0x2098: /* z10 */ + default: + order = 2; + break; + } + + empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); + if (!empty_zero_page) + panic("Out of memory in setup_zero_pages"); + + page = virt_to_page((void *) empty_zero_page); + split_page(page, order); + for (i = 1 << order; i > 0; i--) { + SetPageReserved(page); + page++; + } + + size = PAGE_SIZE << order; + zero_page_mask = (size - 1) & PAGE_MASK; + + return 1UL << order; +} + /* * paging_init() sets up the page tables */ @@ -92,14 +135,12 @@ void __init mem_init(void) max_mapnr = num_physpages = max_low_pfn; high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); - /* clear the zero-page */ - memset(empty_zero_page, 0, PAGE_SIZE); - /* Setup guest page hinting */ cmma_init(); /* this will put all low memory onto the freelists */ totalram_pages += free_all_bootmem(); + totalram_pages -= setup_zero_pages(); /* Setup zeroed pages. */ reservedpages = 0; |