x86: clean up arch/x86/mm/pageattr_64.c
authorIngo Molnar <mingo@elte.hu>
Wed, 30 Jan 2008 12:33:41 +0000 (13:33 +0100)
committerIngo Molnar <mingo@elte.hu>
Wed, 30 Jan 2008 12:33:41 +0000 (13:33 +0100)
clean up arch/x86/mm/pageattr_64.c.

no code changed:

   text    data     bss     dec     hex filename
   1751      16       0    1767     6e7 pageattr_64.o.before
   1751      16       0    1767     6e7 pageattr_64.o.after

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
arch/x86/mm/pageattr_64.c

index c40afbaaf93da9f74e36ef6ca2a2a3e29fa46043..14ab327cde0c920d1ca8a8a4870fee2fae6d97c0 100644 (file)
@@ -1,48 +1,54 @@
-/* 
- * Copyright 2002 Andi Kleen, SuSE Labs. 
+/*
+ * Copyright 2002 Andi Kleen, SuSE Labs.
  * Thanks to Ben LaHaise for precious feedback.
- */ 
+ */
 
-#include <linux/mm.h>
-#include <linux/sched.h>
 #include <linux/highmem.h>
 #include <linux/module.h>
+#include <linux/sched.h>
 #include <linux/slab.h>
-#include <asm/uaccess.h>
+#include <linux/mm.h>
+
 #include <asm/processor.h>
 #include <asm/tlbflush.h>
+#include <asm/uaccess.h>
 #include <asm/io.h>
 
 pte_t *lookup_address(unsigned long address)
-{ 
+{
        pgd_t *pgd = pgd_offset_k(address);
        pud_t *pud;
        pmd_t *pmd;
        pte_t *pte;
+
        if (pgd_none(*pgd))
                return NULL;
        pud = pud_offset(pgd, address);
        if (!pud_present(*pud))
-               return NULL; 
+               return NULL;
        pmd = pmd_offset(pud, address);
        if (!pmd_present(*pmd))
-               return NULL; 
+               return NULL;
        if (pmd_large(*pmd))
                return (pte_t *)pmd;
+
        pte = pte_offset_kernel(pmd, address);
        if (pte && !pte_present(*pte))
-               pte = NULL; 
+               pte = NULL;
+
        return pte;
-} 
+}
 
-static struct page *split_large_page(unsigned long address, pgprot_t prot,
-                                    pgprot_t ref_prot)
-{ 
-       int i; 
+static struct page *
+split_large_page(unsigned long address, pgprot_t prot, pgprot_t ref_prot)
+{
        unsigned long addr;
-       struct page *base = alloc_pages(GFP_KERNEL, 0);
+       struct page *base;
        pte_t *pbase;
-       if (!base) 
+       int i;
+
+       base = alloc_pages(GFP_KERNEL, 0);
+       if (!base)
                return NULL;
        /*
         * page_private is used to track the number of entries in
@@ -52,20 +58,21 @@ static struct page *split_large_page(unsigned long address, pgprot_t prot,
        page_private(base) = 0;
 
        address = __pa(address);
-       addr = address & LARGE_PAGE_MASK; 
+       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, 
+               pbase[i] = pfn_pte(addr >> PAGE_SHIFT,
                                   addr == address ? prot : ref_prot);
        }
        return base;
-} 
+}
 
-void clflush_cache_range(void *adr, int size)
+void clflush_cache_range(void *addr, int size)
 {
        int i;
+
        for (i = 0; i < size; i += boot_cpu_data.x86_clflush_size)
-               clflush(adr+i);
+               clflush(addr+i);
 }
 
 static void flush_kernel_map(void *arg)
@@ -76,17 +83,20 @@ static void flush_kernel_map(void *arg)
        /* When clflush is available always use it because it is
           much cheaper than WBINVD. */
        /* clflush is still broken. Disable for now. */
-       if (1 || !cpu_has_clflush)
+       if (1 || !cpu_has_clflush) {
                asm volatile("wbinvd" ::: "memory");
-       else list_for_each_entry(pg, l, lru) {
-               void *adr = page_address(pg);
-               clflush_cache_range(adr, PAGE_SIZE);
+       } else {
+               list_for_each_entry(pg, l, lru) {
+                       void *addr = page_address(pg);
+
+                       clflush_cache_range(addr, PAGE_SIZE);
+               }
        }
        __flush_tlb_all();
 }
 
 static inline void flush_map(struct list_head *l)
-{      
+{
        on_each_cpu(flush_kernel_map, l, 1, 1);
 }
 
@@ -98,52 +108,56 @@ static inline void save_page(struct page *fpage)
                list_add(&fpage->lru, &deferred_pages);
 }
 
-/* 
+/*
  * No more special protections in this 2/4MB area - revert to a
- * large page again. 
+ * large page again.
  */
 static void revert_page(unsigned long address, pgprot_t ref_prot)
 {
+       unsigned long pfn;
        pgd_t *pgd;
        pud_t *pud;
        pmd_t *pmd;
        pte_t large_pte;
-       unsigned long pfn;
 
        pgd = pgd_offset_k(address);
        BUG_ON(pgd_none(*pgd));
-       pud = pud_offset(pgd,address);
+       pud = pud_offset(pgd, address);
        BUG_ON(pud_none(*pud));
        pmd = pmd_offset(pud, address);
        BUG_ON(pmd_val(*pmd) & _PAGE_PSE);
        pfn = (__pa(address) & LARGE_PAGE_MASK) >> PAGE_SHIFT;
        large_pte = pfn_pte(pfn, ref_prot);
        large_pte = pte_mkhuge(large_pte);
+
        set_pte((pte_t *)pmd, large_pte);
-}      
+}
 
 static int
 __change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot,
-                                  pgprot_t ref_prot)
-{ 
-       pte_t *kpte; 
+                  pgprot_t ref_prot)
+{
        struct page *kpte_page;
        pgprot_t ref_prot2;
+       pte_t *kpte;
 
        kpte = lookup_address(address);
-       if (!kpte) return 0;
+       if (!kpte)
+               return 0;
+
        kpte_page = virt_to_page(((unsigned long)kpte) & PAGE_MASK);
        BUG_ON(PageLRU(kpte_page));
        BUG_ON(PageCompound(kpte_page));
-       if (pgprot_val(prot) != pgprot_val(ref_prot)) { 
+       if (pgprot_val(prot) != pgprot_val(ref_prot)) {
                if (!pte_huge(*kpte)) {
                        set_pte(kpte, pfn_pte(pfn, prot));
                } else {
-                       /*
+                       /*
                         * split_large_page will take the reference for this
                         * change_page_attr on the split page.
-                        */
+                        */
                        struct page *split;
+
                        ref_prot2 = pte_pgprot(pte_clrhuge(*kpte));
                        split = split_large_page(address, prot, ref_prot2);
                        if (!split)
@@ -153,21 +167,23 @@ __change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot,
                        kpte_page = split;
                }
                page_private(kpte_page)++;
-       } else if (!pte_huge(*kpte)) {
-               set_pte(kpte, pfn_pte(pfn, ref_prot));
-               BUG_ON(page_private(kpte_page) == 0);
-               page_private(kpte_page)--;
-       } else
-               BUG();
+       } else {
+               if (!pte_huge(*kpte)) {
+                       set_pte(kpte, pfn_pte(pfn, ref_prot));
+                       BUG_ON(page_private(kpte_page) == 0);
+                       page_private(kpte_page)--;
+               } else
+                       BUG();
+       }
 
        /* on x86-64 the direct mapping set at boot is not using 4k pages */
-       BUG_ON(PageReserved(kpte_page));
+       BUG_ON(PageReserved(kpte_page));
 
        save_page(kpte_page);
        if (page_private(kpte_page) == 0)
                revert_page(address, ref_prot);
        return 0;
-} 
+}
 
 /*
  * Change the page attributes of an page in the linear mapping.
@@ -176,19 +192,19 @@ __change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot,
  * than write-back somewhere - some CPUs do not like it when mappings with
  * different caching policies exist. This changes the page attributes of the
  * in kernel linear mapping too.
- * 
+ *
  * The caller needs to ensure that there are no conflicting mappings elsewhere.
  * This function only deals with the kernel linear map.
- * 
+ *
  * Caller must call global_flush_tlb() after this.
  */
 int change_page_attr_addr(unsigned long address, int numpages, pgprot_t prot)
 {
-       int err = 0, kernel_map = 0;
-       int i; 
+       int err = 0, kernel_map = 0, i;
+
+       if (address >= __START_KERNEL_map &&
+                       address < __START_KERNEL_map + KERNEL_TEXT_SIZE) {
 
-       if (address >= __START_KERNEL_map
-           && address < __START_KERNEL_map + KERNEL_TEXT_SIZE) {
                address = (unsigned long)__va(__pa(address));
                kernel_map = 1;
        }
@@ -198,7 +214,8 @@ int change_page_attr_addr(unsigned long address, int numpages, pgprot_t prot)
                unsigned long pfn = __pa(address) >> PAGE_SHIFT;
 
                if (!kernel_map || pte_present(pfn_pte(0, prot))) {
-                       err = __change_page_attr(address, pfn, prot, PAGE_KERNEL);
+                       err = __change_page_attr(address, pfn, prot,
+                                               PAGE_KERNEL);
                        if (err)
                                break;
                }
@@ -207,14 +224,16 @@ int change_page_attr_addr(unsigned long address, int numpages, pgprot_t prot)
                if (__pa(address) < KERNEL_TEXT_SIZE) {
                        unsigned long addr2;
                        pgprot_t prot2;
+
                        addr2 = __START_KERNEL_map + __pa(address);
                        /* Make sure the kernel mappings stay executable */
                        prot2 = pte_pgprot(pte_mkexec(pfn_pte(0, prot)));
                        err = __change_page_attr(addr2, pfn, prot2,
                                                 PAGE_KERNEL_EXEC);
-               } 
-       }       
-       up_write(&init_mm.mmap_sem); 
+               }
+       }
+       up_write(&init_mm.mmap_sem);
+
        return err;
 }
 
@@ -222,11 +241,13 @@ int change_page_attr_addr(unsigned long address, int numpages, pgprot_t prot)
 int change_page_attr(struct page *page, int numpages, pgprot_t prot)
 {
        unsigned long addr = (unsigned long)page_address(page);
+
        return change_page_attr_addr(addr, numpages, prot);
 }
+EXPORT_SYMBOL(change_page_attr);
 
 void global_flush_tlb(void)
-{ 
+{
        struct page *pg, *next;
        struct list_head l;
 
@@ -248,8 +269,6 @@ void global_flush_tlb(void)
                        continue;
                ClearPagePrivate(pg);
                __free_page(pg);
-       } 
-} 
-
-EXPORT_SYMBOL(change_page_attr);
+       }
+}
 EXPORT_SYMBOL(global_flush_tlb);