From dec7305d9f752f6ad2ec30ec8a723182437c5aa5 Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Tue, 15 Jul 2014 02:49:15 +0400 Subject: [PATCH] xtensa: allow fixmap and kmap span more than one page table To support aliasing cache both kmap region sizes are multiplied by the number of data cache colors. After that expansion page tables that cover kmap regions may become larger than one page. Correctly allocate and initialize page tables in this case. Signed-off-by: Max Filippov --- arch/xtensa/mm/mmu.c | 38 ++++++++++++++++++++++---------------- 1 file changed, 22 insertions(+), 16 deletions(-) diff --git a/arch/xtensa/mm/mmu.c b/arch/xtensa/mm/mmu.c index 3429b483d9f8..abe4513eb0dd 100644 --- a/arch/xtensa/mm/mmu.c +++ b/arch/xtensa/mm/mmu.c @@ -18,32 +18,38 @@ #include #if defined(CONFIG_HIGHMEM) -static void * __init init_pmd(unsigned long vaddr) +static void * __init init_pmd(unsigned long vaddr, unsigned long n_pages) { pgd_t *pgd = pgd_offset_k(vaddr); pmd_t *pmd = pmd_offset(pgd, vaddr); + pte_t *pte; + unsigned long i; - if (pmd_none(*pmd)) { - unsigned i; - pte_t *pte = alloc_bootmem_low_pages(PAGE_SIZE); + n_pages = ALIGN(n_pages, PTRS_PER_PTE); - for (i = 0; i < 1024; i++) - pte_clear(NULL, 0, pte + i); + pr_debug("%s: vaddr: 0x%08lx, n_pages: %ld\n", + __func__, vaddr, n_pages); - set_pmd(pmd, __pmd(((unsigned long)pte) & PAGE_MASK)); - BUG_ON(pte != pte_offset_kernel(pmd, 0)); - pr_debug("%s: vaddr: 0x%08lx, pmd: 0x%p, pte: 0x%p\n", - __func__, vaddr, pmd, pte); - return pte; - } else { - return pte_offset_kernel(pmd, 0); + pte = alloc_bootmem_low_pages(n_pages * sizeof(pte_t)); + + for (i = 0; i < n_pages; ++i) + pte_clear(NULL, 0, pte + i); + + for (i = 0; i < n_pages; i += PTRS_PER_PTE, ++pmd) { + pte_t *cur_pte = pte + i; + + BUG_ON(!pmd_none(*pmd)); + set_pmd(pmd, __pmd(((unsigned long)cur_pte) & PAGE_MASK)); + BUG_ON(cur_pte != pte_offset_kernel(pmd, 0)); + pr_debug("%s: pmd: 0x%p, pte: 0x%p\n", + __func__, pmd, cur_pte); } + return pte; } static void __init fixedrange_init(void) { - BUILD_BUG_ON(FIXADDR_SIZE > PMD_SIZE); - init_pmd(__fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK); + init_pmd(__fix_to_virt(0), __end_of_fixed_addresses); } #endif @@ -52,7 +58,7 @@ void __init paging_init(void) memset(swapper_pg_dir, 0, PAGE_SIZE); #ifdef CONFIG_HIGHMEM fixedrange_init(); - pkmap_page_table = init_pmd(PKMAP_BASE); + pkmap_page_table = init_pmd(PKMAP_BASE, LAST_PKMAP); kmap_init(); #endif } -- 2.39.5