x86, mm: only call early_ioremap_page_table_range_init() once

On 32bit, before patcheset that only set page table for ram, we only
call that one time.

Now, we are calling that during every init_memory_mapping if we have holes
under max_low_pfn.

We should only call it one time after all ranges under max_low_page get
mapped just like we did before.

Also that could avoid the risk to run out of pgt_buf in BRK.

Need to update page_table_range_init() to count the pages for kmap page table
at first, and use new added alloc_low_pages() to get pages in sequence.
That will conform to the requirement that pages need to be in low to high order.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1353123563-3103-30-git-send-email-yinghai@kernel.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index cb4f8ba70eccba475e67e9de9fd0dbc75fef593c..bed4888c6f4f87135ae2350287397703d6a11ed4 100644 (file)
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -343,14 +343,6 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
                ret = kernel_physical_mapping_init(mr[i].start, mr[i].end,
                                                   mr[i].page_size_mask);
 
-#ifdef CONFIG_X86_32
-       early_ioremap_page_table_range_init();
-
-       load_cr3(swapper_pg_dir);
-#endif
-
-       __flush_tlb_all();
-
        add_pfn_range_mapped(start >> PAGE_SHIFT, ret >> PAGE_SHIFT);
 
        return ret >> PAGE_SHIFT;
@@ -447,7 +439,12 @@ void __init init_mem_mapping(void)
                /* can we preseve max_low_pfn ?*/
                max_low_pfn = max_pfn;
        }
+#else
+       early_ioremap_page_table_range_init();
+       load_cr3(swapper_pg_dir);
+       __flush_tlb_all();
 #endif
+
        early_memtest(0, max_pfn_mapped << PAGE_SHIFT);
 }
 

diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index a7f2df1cdcfd972807a01ae016d6fd3ad695249b..0ae1ba8bc1b9dd47645787eddf16d07ac594c28a 100644 (file)
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -135,8 +135,39 @@ pte_t * __init populate_extra_pte(unsigned long vaddr)
        return one_page_table_init(pmd) + pte_idx;
 }
 
+static unsigned long __init
+page_table_range_init_count(unsigned long start, unsigned long end)
+{
+       unsigned long count = 0;
+#ifdef CONFIG_HIGHMEM
+       int pmd_idx_kmap_begin = fix_to_virt(FIX_KMAP_END) >> PMD_SHIFT;
+       int pmd_idx_kmap_end = fix_to_virt(FIX_KMAP_BEGIN) >> PMD_SHIFT;
+       int pgd_idx, pmd_idx;
+       unsigned long vaddr;
+
+       if (pmd_idx_kmap_begin == pmd_idx_kmap_end)
+               return 0;
+
+       vaddr = start;
+       pgd_idx = pgd_index(vaddr);
+
+       for ( ; (pgd_idx < PTRS_PER_PGD) && (vaddr != end); pgd_idx++) {
+               for (; (pmd_idx < PTRS_PER_PMD) && (vaddr != end);
+                                                       pmd_idx++) {
+                       if ((vaddr >> PMD_SHIFT) >= pmd_idx_kmap_begin &&
+                           (vaddr >> PMD_SHIFT) <= pmd_idx_kmap_end)
+                               count++;
+                       vaddr += PMD_SIZE;
+               }
+               pmd_idx = 0;
+       }
+#endif
+       return count;
+}
+
 static pte_t *__init page_table_kmap_check(pte_t *pte, pmd_t *pmd,
-                                          unsigned long vaddr, pte_t *lastpte)
+                                          unsigned long vaddr, pte_t *lastpte,
+                                          void **adr)
 {
 #ifdef CONFIG_HIGHMEM
        /*
@@ -150,16 +181,15 @@ static pte_t *__init page_table_kmap_check(pte_t *pte, pmd_t *pmd,
 
        if (pmd_idx_kmap_begin != pmd_idx_kmap_end
            && (vaddr >> PMD_SHIFT) >= pmd_idx_kmap_begin
-           && (vaddr >> PMD_SHIFT) <= pmd_idx_kmap_end
-           && ((__pa(pte) >> PAGE_SHIFT) < pgt_buf_start
-               || (__pa(pte) >> PAGE_SHIFT) >= pgt_buf_end)) {
+           && (vaddr >> PMD_SHIFT) <= pmd_idx_kmap_end) {
                pte_t *newpte;
                int i;
 
                BUG_ON(after_bootmem);
-               newpte = alloc_low_page();
+               newpte = *adr;
                for (i = 0; i < PTRS_PER_PTE; i++)
                        set_pte(newpte + i, pte[i]);
+               *adr = (void *)(((unsigned long)(*adr)) + PAGE_SIZE);
 
                paravirt_alloc_pte(&init_mm, __pa(newpte) >> PAGE_SHIFT);
                set_pmd(pmd, __pmd(__pa(newpte)|_PAGE_TABLE));
@@ -193,6 +223,11 @@ page_table_range_init(unsigned long start, unsigned long end, pgd_t *pgd_base)
        pgd_t *pgd;
        pmd_t *pmd;
        pte_t *pte = NULL;
+       unsigned long count = page_table_range_init_count(start, end);
+       void *adr = NULL;
+
+       if (count)
+               adr = alloc_low_pages(count);
 
        vaddr = start;
        pgd_idx = pgd_index(vaddr);
@@ -205,7 +240,7 @@ page_table_range_init(unsigned long start, unsigned long end, pgd_t *pgd_base)
                for (; (pmd_idx < PTRS_PER_PMD) && (vaddr != end);
                                                        pmd++, pmd_idx++) {
                        pte = page_table_kmap_check(one_page_table_init(pmd),
-                                                   pmd, vaddr, pte);
+                                                   pmd, vaddr, pte, &adr);
 
                        vaddr += PMD_SIZE;
                }