Fedora kernel-2.6.17-1.2142_FC4 patched with stable patch-2.6.17.4-vs2.0.2-rc26.diff

[linux-2.6.git] / arch / i386 / mm / pageattr.c

diff --git a/arch/i386/mm/pageattr.c b/arch/i386/mm/pageattr.c
index cb3da6b..92c3d9f 100644 (file)
--- a/arch/i386/mm/pageattr.c
+++ b/arch/i386/mm/pageattr.c
@@ -12,6 +12,8 @@
 #include <asm/uaccess.h>
 #include <asm/processor.h>
 #include <asm/tlbflush.h>
+#include <asm/pgalloc.h>
+#include <asm/sections.h>
 
 static DEFINE_SPINLOCK(cpa_lock);
 static struct list_head df_list = LIST_HEAD_INIT(df_list);
@@ -35,7 +37,8 @@ pte_t *lookup_address(unsigned long address)
         return pte_offset_kernel(pmd, address);
 } 
 
-static struct page *split_large_page(unsigned long address, pgprot_t prot)
+static struct page *split_large_page(unsigned long address, pgprot_t prot,
+                                       pgprot_t ref_prot)
 { 
        int i; 
        unsigned long addr;
@@ -48,12 +51,19 @@ static struct page *split_large_page(unsigned long address, pgprot_t prot)
        if (!base) 
                return NULL;
 
+       /*
+        * page_private is used to track the number of entries in
+        * the page table page that have non standard attributes.
+        */
+       SetPagePrivate(base);
+       page_private(base) = 0;
+
        address = __pa(address);
        addr = address & LARGE_PAGE_MASK; 
        pbase = (pte_t *)page_address(base);
        for (i = 0; i < PTRS_PER_PTE; i++, addr += PAGE_SIZE) {
-               pbase[i] = pfn_pte(addr >> PAGE_SHIFT, 
-                                  addr == address ? prot : PAGE_KERNEL);
+               set_pte(&pbase[i], pfn_pte(addr >> PAGE_SHIFT,
+                                          addr == address ? prot : ref_prot));
        }
        return base;
 } 
@@ -62,7 +72,7 @@ static void flush_kernel_map(void *dummy)
 { 
        /* Could use CLFLUSH here if the CPU supports it (Hammer,P4) */
        if (boot_cpu_data.x86_model >= 4) 
-               asm volatile("wbinvd":::"memory"); 
+               wbinvd();
        /* Flush all to work around Errata in early athlons regarding 
         * large page flushing. 
         */
@@ -97,11 +107,18 @@ static void set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte)
  */
 static inline void revert_page(struct page *kpte_page, unsigned long address)
 {
-       pte_t *linear = (pte_t *) 
+       pgprot_t ref_prot;
+       pte_t *linear;
+
+       ref_prot =
+       ((address & LARGE_PAGE_MASK) < (unsigned long)&_etext)
+               ? PAGE_KERNEL_LARGE_EXEC : PAGE_KERNEL_LARGE;
+
+       linear = (pte_t *)
                pmd_offset(pud_offset(pgd_offset_k(address), address), address);
        set_pmd_pte(linear,  address,
                    pfn_pte((__pa(address) & LARGE_PAGE_MASK) >> PAGE_SHIFT,
-                           PAGE_KERNEL_LARGE));
+                           ref_prot));
 }
 
 static int
@@ -122,16 +139,23 @@ __change_page_attr(struct page *page, pgprot_t prot)
                if ((pte_val(*kpte) & _PAGE_PSE) == 0) { 
                        set_pte_atomic(kpte, mk_pte(page, prot)); 
                } else {
-                       struct page *split = split_large_page(address, prot); 
+                       pgprot_t ref_prot;
+                       struct page *split;
+
+                       ref_prot =
+                       ((address & LARGE_PAGE_MASK) < (unsigned long)&_etext)
+                               ? PAGE_KERNEL_EXEC : PAGE_KERNEL;
+                       split = split_large_page(address, prot, ref_prot);
                        if (!split)
                                return -ENOMEM;
-                       set_pmd_pte(kpte,address,mk_pte(split, PAGE_KERNEL));
+                       set_pmd_pte(kpte,address,mk_pte(split, ref_prot));
                        kpte_page = split;
-               }       
-               get_page(kpte_page);
+               }
+               page_private(kpte_page)++;
        } else if ((pte_val(*kpte) & _PAGE_PSE) == 0) { 
                set_pte_atomic(kpte, mk_pte(page, PAGE_KERNEL));
-               __put_page(kpte_page);
+               BUG_ON(page_private(kpte_page) == 0);
+               page_private(kpte_page)--;
        } else
                BUG();
 
@@ -141,10 +165,8 @@ __change_page_attr(struct page *page, pgprot_t prot)
         * replace it with a largepage.
         */
        if (!PageReserved(kpte_page)) {
-               /* memleak and potential failed 2M page regeneration */
-               BUG_ON(!page_count(kpte_page));
-
-               if (cpu_has_pse && (page_count(kpte_page) == 1)) {
+               if (cpu_has_pse && (page_private(kpte_page) == 0)) {
+                       ClearPagePrivate(kpte_page);
                        list_add(&kpte_page->lru, &df_list);
                        revert_page(kpte_page, address);
                }
@@ -206,6 +228,10 @@ void kernel_map_pages(struct page *page, int numpages, int enable)
 {
        if (PageHighMem(page))
                return;
+       if (!enable)
+               mutex_debug_check_no_locks_freed(page_address(page),
+                                                numpages * PAGE_SIZE);
+
        /* the return value is ignored - the calls cannot fail,
         * large pages are disabled at boot time.
         */