x86, generic: CPA add statistics about state of direct mapping v4

[linux-2.6-omap-h63xx.git] / arch / x86 / mm / pageattr.c

diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 270cab2e6030050e8bd76ebf628bab8236fedfb2..668205bca15eb46ae3a6871294b08e7943364190 100644 (file)
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -31,8 +31,22 @@ struct cpa_data {
        int             numpages;
        int             flushtlb;
        unsigned long   pfn;
+       unsigned        force_split : 1;
 };
 
+static unsigned long direct_pages_count[PG_LEVEL_NUM];
+
+void __meminit update_page_count(int level, unsigned long pages)
+{
+#ifdef CONFIG_PROC_FS
+       unsigned long flags;
+       /* Protect against CPA */
+       spin_lock_irqsave(&pgd_lock, flags);
+       direct_pages_count[level] += pages;
+       spin_unlock_irqrestore(&pgd_lock, flags);
+#endif
+}
+
 #ifdef CONFIG_X86_64
 
 static inline unsigned long highmap_start_pfn(void)
@@ -262,6 +276,9 @@ try_preserve_large_page(pte_t *kpte, unsigned long address,
        int i, do_split = 1;
        unsigned int level;
 
+       if (cpa->force_split)
+               return 1;
+
        spin_lock_irqsave(&pgd_lock, flags);
        /*
         * Check for races, another CPU might have split this page
@@ -479,9 +496,7 @@ static int split_large_page(pte_t *kpte, unsigned long address)
                goto out_unlock;
 
        pbase = (pte_t *)page_address(base);
-#ifdef CONFIG_X86_32
-       paravirt_alloc_pt(&init_mm, page_to_pfn(base));
-#endif
+       paravirt_alloc_pte(&init_mm, page_to_pfn(base));
        ref_prot = pte_pgprot(pte_clrhuge(*kpte));
 
 #ifdef CONFIG_X86_64
@@ -498,6 +513,12 @@ static int split_large_page(pte_t *kpte, unsigned long address)
        for (i = 0; i < PTRS_PER_PTE; i++, pfn += pfninc)
                set_pte(&pbase[i], pfn_pte(pfn, ref_prot));
 
+       if (address >= (unsigned long)__va(0) &&
+               address < (unsigned long)__va(max_pfn_mapped << PAGE_SHIFT)) {
+               direct_pages_count[level]--;
+               direct_pages_count[level - 1] += PTRS_PER_PTE;
+       }
+
        /*
         * Install the new, split up pagetable. Important details here:
         *
@@ -538,7 +559,7 @@ static int __change_page_attr(struct cpa_data *cpa, int primary)
 repeat:
        kpte = lookup_address(address, &level);
        if (!kpte)
-               return primary ? -EINVAL : 0;
+               return 0;
 
        old_pte = *kpte;
        if (!pte_val(old_pte)) {
@@ -696,7 +717,8 @@ static inline int cache_attr(pgprot_t attr)
 }
 
 static int change_page_attr_set_clr(unsigned long addr, int numpages,
-                                   pgprot_t mask_set, pgprot_t mask_clr)
+                                   pgprot_t mask_set, pgprot_t mask_clr,
+                                   int force_split)
 {
        struct cpa_data cpa;
        int ret, cache, checkalias;
@@ -707,7 +729,7 @@ static int change_page_attr_set_clr(unsigned long addr, int numpages,
         */
        mask_set = canon_pgprot(mask_set);
        mask_clr = canon_pgprot(mask_clr);
-       if (!pgprot_val(mask_set) && !pgprot_val(mask_clr))
+       if (!pgprot_val(mask_set) && !pgprot_val(mask_clr) && !force_split)
                return 0;
 
        /* Ensure we are PAGE_SIZE aligned */
@@ -724,6 +746,7 @@ static int change_page_attr_set_clr(unsigned long addr, int numpages,
        cpa.mask_set = mask_set;
        cpa.mask_clr = mask_clr;
        cpa.flushtlb = 0;
+       cpa.force_split = force_split;
 
        /* No alias checking for _NX bit modifications */
        checkalias = (pgprot_val(mask_set) | pgprot_val(mask_clr)) != _PAGE_NX;
@@ -762,25 +785,31 @@ out:
 static inline int change_page_attr_set(unsigned long addr, int numpages,
                                       pgprot_t mask)
 {
-       return change_page_attr_set_clr(addr, numpages, mask, __pgprot(0));
+       return change_page_attr_set_clr(addr, numpages, mask, __pgprot(0), 0);
 }
 
 static inline int change_page_attr_clear(unsigned long addr, int numpages,
                                         pgprot_t mask)
 {
-       return change_page_attr_set_clr(addr, numpages, __pgprot(0), mask);
+       return change_page_attr_set_clr(addr, numpages, __pgprot(0), mask, 0);
 }
 
 int _set_memory_uc(unsigned long addr, int numpages)
 {
+       /*
+        * for now UC MINUS. see comments in ioremap_nocache()
+        */
        return change_page_attr_set(addr, numpages,
-                                   __pgprot(_PAGE_CACHE_UC));
+                                   __pgprot(_PAGE_CACHE_UC_MINUS));
 }
 
 int set_memory_uc(unsigned long addr, int numpages)
 {
+       /*
+        * for now UC MINUS. see comments in ioremap_nocache()
+        */
        if (reserve_memtype(addr, addr + numpages * PAGE_SIZE,
-                           _PAGE_CACHE_UC, NULL))
+                           _PAGE_CACHE_UC_MINUS, NULL))
                return -EINVAL;
 
        return _set_memory_uc(addr, numpages);
@@ -847,6 +876,12 @@ int set_memory_np(unsigned long addr, int numpages)
        return change_page_attr_clear(addr, numpages, __pgprot(_PAGE_PRESENT));
 }
 
+int set_memory_4k(unsigned long addr, int numpages)
+{
+       return change_page_attr_set_clr(addr, numpages, __pgprot(0),
+                                       __pgprot(0), 1);
+}
+
 int set_pages_uc(struct page *page, int numpages)
 {
        unsigned long addr = (unsigned long)page_address(page);
@@ -981,7 +1016,7 @@ static const struct file_operations dpa_fops = {
        .release        = single_release,
 };
 
-int __init debug_pagealloc_proc_init(void)
+static int __init debug_pagealloc_proc_init(void)
 {
        struct dentry *de;
 
@@ -1013,6 +1048,22 @@ bool kernel_page_present(struct page *page)
 
 #endif /* CONFIG_DEBUG_PAGEALLOC */
 
+#ifdef CONFIG_PROC_FS
+int arch_report_meminfo(char *page)
+{
+       int n;
+       n = sprintf(page, "DirectMap4k:  %8lu\n"
+                         "DirectMap2M:  %8lu\n",
+                       direct_pages_count[PG_LEVEL_4K],
+                       direct_pages_count[PG_LEVEL_2M]);
+#ifdef CONFIG_X86_64
+       n += sprintf(page + n, "DirectMap1G:  %8lu\n",
+                       direct_pages_count[PG_LEVEL_1G]);
+#endif
+       return n;
+}
+#endif
+
 /*
  * The testcases use internal knowledge of the implementation that shouldn't
  * be exposed to the rest of the kernel. Include these directly here.