]> nv-tegra.nvidia Code Review - linux-2.6.git/blobdiff - arch/x86/mm/pageattr.c
Merge branch 'x86/urgent' into x86/xen
[linux-2.6.git] / arch / x86 / mm / pageattr.c
index 143fbafc948ae25c9c8added4a1a7534c0521d9f..b81b41a0481f8a42924c78b036ab2630722fefeb 100644 (file)
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/seq_file.h>
+#include <linux/debugfs.h>
 
 #include <asm/e820.h>
 #include <asm/processor.h>
 #include <asm/tlbflush.h>
 #include <asm/sections.h>
+#include <asm/setup.h>
 #include <asm/uaccess.h>
 #include <asm/pgalloc.h>
+#include <asm/proto.h>
+#include <asm/pat.h>
 
+/*
+ * The current flushing context - we pass it instead of 5 arguments:
+ */
 struct cpa_data {
-       unsigned long   vaddr;
+       unsigned long   *vaddr;
        pgprot_t        mask_set;
        pgprot_t        mask_clr;
        int             numpages;
-       int             flushtlb;
+       int             flags;
+       unsigned long   pfn;
+       unsigned        force_split : 1;
+       int             curpage;
+       struct page     **pages;
 };
 
-enum {
-       CPA_NO_SPLIT = 0,
-       CPA_SPLIT,
-};
+/*
+ * Serialize cpa() (for !DEBUG_PAGEALLOC which uses large identity mappings)
+ * using cpa_lock. So that we don't allow any other cpu, with stale large tlb
+ * entries change the page attribute in parallel to some other cpu
+ * splitting a large page entry along with changing the attribute.
+ */
+static DEFINE_SPINLOCK(cpa_lock);
+
+#define CPA_FLUSHTLB 1
+#define CPA_ARRAY 2
+#define CPA_PAGES_ARRAY 4
+
+#ifdef CONFIG_PROC_FS
+static unsigned long direct_pages_count[PG_LEVEL_NUM];
+
+void update_page_count(int level, unsigned long pages)
+{
+       unsigned long flags;
+
+       /* Protect against CPA */
+       spin_lock_irqsave(&pgd_lock, flags);
+       direct_pages_count[level] += pages;
+       spin_unlock_irqrestore(&pgd_lock, flags);
+}
+
+static void split_page_count(int level)
+{
+       direct_pages_count[level]--;
+       direct_pages_count[level - 1] += PTRS_PER_PTE;
+}
+
+void arch_report_meminfo(struct seq_file *m)
+{
+       seq_printf(m, "DirectMap4k:    %8lu kB\n",
+                       direct_pages_count[PG_LEVEL_4K] << 2);
+#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
+       seq_printf(m, "DirectMap2M:    %8lu kB\n",
+                       direct_pages_count[PG_LEVEL_2M] << 11);
+#else
+       seq_printf(m, "DirectMap4M:    %8lu kB\n",
+                       direct_pages_count[PG_LEVEL_2M] << 12);
+#endif
+#ifdef CONFIG_X86_64
+       if (direct_gbpages)
+               seq_printf(m, "DirectMap1G:    %8lu kB\n",
+                       direct_pages_count[PG_LEVEL_1G] << 20);
+#endif
+}
+#else
+static inline void split_page_count(int level) { }
+#endif
+
+#ifdef CONFIG_X86_64
+
+static inline unsigned long highmap_start_pfn(void)
+{
+       return __pa(_text) >> PAGE_SHIFT;
+}
+
+static inline unsigned long highmap_end_pfn(void)
+{
+       return __pa(roundup(_brk_end, PMD_SIZE)) >> PAGE_SHIFT;
+}
+
+#endif
+
+#ifdef CONFIG_DEBUG_PAGEALLOC
+# define debug_pagealloc 1
+#else
+# define debug_pagealloc 0
+#endif
 
 static inline int
 within(unsigned long addr, unsigned long start, unsigned long end)
@@ -81,7 +161,7 @@ static void cpa_flush_all(unsigned long cache)
 {
        BUG_ON(irqs_disabled());
 
-       on_each_cpu(__cpa_flush_all, (void *) cache, 1, 1);
+       on_each_cpu(__cpa_flush_all, (void *) cache, 1);
 }
 
 static void __cpa_flush_range(void *arg)
@@ -102,7 +182,7 @@ static void cpa_flush_range(unsigned long start, int numpages, int cache)
        BUG_ON(irqs_disabled());
        WARN_ON(PAGE_ALIGN(start) != start);
 
-       on_each_cpu(__cpa_flush_range, NULL, 1, 1);
+       on_each_cpu(__cpa_flush_range, NULL, 1);
 
        if (!cache)
                return;
@@ -124,20 +204,47 @@ static void cpa_flush_range(unsigned long start, int numpages, int cache)
        }
 }
 
-#define HIGH_MAP_START __START_KERNEL_map
-#define HIGH_MAP_END   (__START_KERNEL_map + KERNEL_TEXT_SIZE)
+static void cpa_flush_array(unsigned long *start, int numpages, int cache,
+                           int in_flags, struct page **pages)
+{
+       unsigned int i, level;
 
+       BUG_ON(irqs_disabled());
 
-/*
- * Converts a virtual address to a X86-64 highmap address
- */
-static unsigned long virt_to_highmap(void *address)
-{
-#ifdef CONFIG_X86_64
-       return __pa((unsigned long)address) + HIGH_MAP_START - phys_base;
-#else
-       return (unsigned long)address;
-#endif
+       on_each_cpu(__cpa_flush_range, NULL, 1);
+
+       if (!cache)
+               return;
+
+       /* 4M threshold */
+       if (numpages >= 1024) {
+               if (boot_cpu_data.x86_model >= 4)
+                       wbinvd();
+               return;
+       }
+       /*
+        * We only need to flush on one CPU,
+        * clflush is a MESI-coherent instruction that
+        * will cause all other CPUs to flush the same
+        * cachelines:
+        */
+       for (i = 0; i < numpages; i++) {
+               unsigned long addr;
+               pte_t *pte;
+
+               if (in_flags & CPA_PAGES_ARRAY)
+                       addr = (unsigned long)page_address(pages[i]);
+               else
+                       addr = start[i];
+
+               pte = lookup_address(addr, &level);
+
+               /*
+                * Only flush present addresses:
+                */
+               if (pte && (pte_val(*pte) & _PAGE_PRESENT))
+                       clflush_cache_range((void *)addr, PAGE_SIZE);
+       }
 }
 
 /*
@@ -146,7 +253,8 @@ static unsigned long virt_to_highmap(void *address)
  * right (again, ioremap() on BIOS memory is not uncommon) so this function
  * checks and fixes these known static required protection bits.
  */
-static inline pgprot_t static_protections(pgprot_t prot, unsigned long address)
+static inline pgprot_t static_protections(pgprot_t prot, unsigned long address,
+                                  unsigned long pfn)
 {
        pgprot_t forbidden = __pgprot(0);
 
@@ -154,34 +262,24 @@ static inline pgprot_t static_protections(pgprot_t prot, unsigned long address)
         * The BIOS area between 640k and 1Mb needs to be executable for
         * PCI BIOS based config access (CONFIG_PCI_GOBIOS) support.
         */
-       if (within(__pa(address), BIOS_BEGIN, BIOS_END))
+       if (within(pfn, BIOS_BEGIN >> PAGE_SHIFT, BIOS_END >> PAGE_SHIFT))
                pgprot_val(forbidden) |= _PAGE_NX;
 
        /*
         * The kernel text needs to be executable for obvious reasons
-        * Does not cover __inittext since that is gone later on
+        * Does not cover __inittext since that is gone later on. On
+        * 64bit we do not enforce !NX on the low mapping
         */
        if (within(address, (unsigned long)_text, (unsigned long)_etext))
                pgprot_val(forbidden) |= _PAGE_NX;
-       /*
-        * Do the same for the x86-64 high kernel mapping
-        */
-       if (within(address, virt_to_highmap(_text), virt_to_highmap(_etext)))
-               pgprot_val(forbidden) |= _PAGE_NX;
-
 
-#ifdef CONFIG_DEBUG_RODATA
-       /* The .rodata section needs to be read-only */
-       if (within(address, (unsigned long)__start_rodata,
-                               (unsigned long)__end_rodata))
-               pgprot_val(forbidden) |= _PAGE_RW;
        /*
-        * Do the same for the x86-64 high kernel mapping
+        * The .rodata section needs to be read-only. Using the pfn
+        * catches all aliases.
         */
-       if (within(address, virt_to_highmap(__start_rodata),
-                               virt_to_highmap(__end_rodata)))
+       if (within(pfn, __pa((unsigned long)__start_rodata) >> PAGE_SHIFT,
+                  __pa((unsigned long)__end_rodata) >> PAGE_SHIFT))
                pgprot_val(forbidden) |= _PAGE_RW;
-#endif
 
        prot = __pgprot(pgprot_val(prot) & ~pgprot_val(forbidden));
 
@@ -196,7 +294,7 @@ static inline pgprot_t static_protections(pgprot_t prot, unsigned long address)
  * or when the present bit is not set. Otherwise we would return a
  * pointer to a nonexisting mapping.
  */
-pte_t *lookup_address(unsigned long address, int *level)
+pte_t *lookup_address(unsigned long address, unsigned int *level)
 {
        pgd_t *pgd = pgd_offset_k(address);
        pud_t *pud;
@@ -206,6 +304,7 @@ pte_t *lookup_address(unsigned long address, int *level)
 
        if (pgd_none(*pgd))
                return NULL;
+
        pud = pud_offset(pgd, address);
        if (pud_none(*pud))
                return NULL;
@@ -223,9 +322,14 @@ pte_t *lookup_address(unsigned long address, int *level)
                return (pte_t *)pmd;
 
        *level = PG_LEVEL_4K;
+
        return pte_offset_kernel(pmd, address);
 }
+EXPORT_SYMBOL_GPL(lookup_address);
 
+/*
+ * Set the new pmd in all the pgds we know about:
+ */
 static void __set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte)
 {
        /* change init_mm */
@@ -248,24 +352,18 @@ static void __set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte)
 #endif
 }
 
-static int try_preserve_large_page(pte_t *kpte, unsigned long address,
-                                  struct cpa_data *cpa)
+static int
+try_preserve_large_page(pte_t *kpte, unsigned long address,
+                       struct cpa_data *cpa)
 {
-       unsigned long nextpage_addr, numpages, pmask, psize, flags;
+       unsigned long nextpage_addr, numpages, pmask, psize, flags, addr, pfn;
        pte_t new_pte, old_pte, *tmp;
        pgprot_t old_prot, new_prot;
-       int level, res = CPA_SPLIT;
+       int i, do_split = 1;
+       unsigned int level;
 
-       /*
-        * An Athlon 64 X2 showed hard hangs if we tried to preserve
-        * largepages and changed the PSE entry from RW to RO.
-        *
-        * As AMD CPUs have a long series of erratas in this area,
-        * (and none of the known ones seem to explain this hang),
-        * disable this code until the hang can be debugged:
-        */
-       if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
-               return res;
+       if (cpa->force_split)
+               return 1;
 
        spin_lock_irqsave(&pgd_lock, flags);
        /*
@@ -281,9 +379,14 @@ static int try_preserve_large_page(pte_t *kpte, unsigned long address,
                psize = PMD_PAGE_SIZE;
                pmask = PMD_PAGE_MASK;
                break;
+#ifdef CONFIG_X86_64
        case PG_LEVEL_1G:
+               psize = PUD_PAGE_SIZE;
+               pmask = PUD_PAGE_MASK;
+               break;
+#endif
        default:
-               res = -EINVAL;
+               do_split = -EINVAL;
                goto out_unlock;
        }
 
@@ -304,14 +407,36 @@ static int try_preserve_large_page(pte_t *kpte, unsigned long address,
 
        pgprot_val(new_prot) &= ~pgprot_val(cpa->mask_clr);
        pgprot_val(new_prot) |= pgprot_val(cpa->mask_set);
-       new_prot = static_protections(new_prot, address);
+
+       /*
+        * old_pte points to the large page base address. So we need
+        * to add the offset of the virtual address:
+        */
+       pfn = pte_pfn(old_pte) + ((address & (psize - 1)) >> PAGE_SHIFT);
+       cpa->pfn = pfn;
+
+       new_prot = static_protections(new_prot, address, pfn);
+
+       /*
+        * We need to check the full range, whether
+        * static_protection() requires a different pgprot for one of
+        * the pages in the range we try to preserve:
+        */
+       addr = address + PAGE_SIZE;
+       pfn++;
+       for (i = 1; i < cpa->numpages; i++, addr += PAGE_SIZE, pfn++) {
+               pgprot_t chk_prot = static_protections(new_prot, addr, pfn);
+
+               if (pgprot_val(chk_prot) != pgprot_val(new_prot))
+                       goto out_unlock;
+       }
 
        /*
         * If there are no changes, return. maxpages has been updated
         * above:
         */
        if (pgprot_val(new_prot) == pgprot_val(old_prot)) {
-               res = CPA_NO_SPLIT;
+               do_split = 0;
                goto out_unlock;
        }
 
@@ -330,28 +455,29 @@ static int try_preserve_large_page(pte_t *kpte, unsigned long address,
                 */
                new_pte = pfn_pte(pte_pfn(old_pte), canon_pgprot(new_prot));
                __set_pmd_pte(kpte, address, new_pte);
-               cpa->flushtlb = 1;
-               res = CPA_NO_SPLIT;
+               cpa->flags |= CPA_FLUSHTLB;
+               do_split = 0;
        }
 
 out_unlock:
        spin_unlock_irqrestore(&pgd_lock, flags);
-       return res;
+
+       return do_split;
 }
 
 static int split_large_page(pte_t *kpte, unsigned long address)
 {
-       pgprot_t ref_prot;
-       gfp_t gfp_flags = GFP_KERNEL;
-       unsigned long flags, addr, pfn;
+       unsigned long flags, pfn, pfninc = 1;
+       unsigned int i, level;
        pte_t *pbase, *tmp;
+       pgprot_t ref_prot;
        struct page *base;
-       unsigned int i, level;
 
-#ifdef CONFIG_DEBUG_PAGEALLOC
-       gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
-#endif
-       base = alloc_pages(gfp_flags, 0);
+       if (!debug_pagealloc)
+               spin_unlock(&cpa_lock);
+       base = alloc_pages(GFP_KERNEL, 0);
+       if (!debug_pagealloc)
+               spin_lock(&cpa_lock);
        if (!base)
                return -ENOMEM;
 
@@ -364,90 +490,149 @@ static int split_large_page(pte_t *kpte, unsigned long address)
        if (tmp != kpte)
                goto out_unlock;
 
-       address = __pa(address);
-       addr = address & PMD_PAGE_MASK;
        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));
+       /*
+        * If we ever want to utilize the PAT bit, we need to
+        * update this function to make sure it's converted from
+        * bit 12 to bit 7 when we cross from the 2MB level to
+        * the 4K level:
+        */
+       WARN_ON_ONCE(pgprot_val(ref_prot) & _PAGE_PAT_LARGE);
+
+#ifdef CONFIG_X86_64
+       if (level == PG_LEVEL_1G) {
+               pfninc = PMD_PAGE_SIZE >> PAGE_SHIFT;
+               pgprot_val(ref_prot) |= _PAGE_PSE;
+       }
+#endif
 
        /*
         * Get the target pfn from the original entry:
         */
        pfn = pte_pfn(*kpte);
-       for (i = 0; i < PTRS_PER_PTE; i++, pfn++)
+       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_low_pfn_mapped << PAGE_SHIFT))
+               split_page_count(level);
+
+#ifdef CONFIG_X86_64
+       if (address >= (unsigned long)__va(1UL<<32) &&
+               address < (unsigned long)__va(max_pfn_mapped << PAGE_SHIFT))
+               split_page_count(level);
+#endif
+
        /*
-        * Install the new, split up pagetable. Important details here:
+        * Install the new, split up pagetable.
         *
-        * On Intel the NX bit of all levels must be cleared to make a
-        * page executable. See section 4.13.2 of Intel 64 and IA-32
-        * Architectures Software Developer's Manual).
+        * We use the standard kernel pagetable protections for the new
+        * pagetable protections, the actual ptes set above control the
+        * primary protection behavior:
+        */
+       __set_pmd_pte(kpte, address, mk_pte(base, __pgprot(_KERNPG_TABLE)));
+
+       /*
+        * Intel Atom errata AAH41 workaround.
         *
-        * Mark the entry present. The current mapping might be
-        * set to not present, which we preserved above.
+        * The real fix should be in hw or in a microcode update, but
+        * we also probabilistically try to reduce the window of having
+        * a large TLB mixed with 4K TLBs while instruction fetches are
+        * going on.
         */
-       ref_prot = pte_pgprot(pte_mkexec(pte_clrhuge(*kpte)));
-       pgprot_val(ref_prot) |= _PAGE_PRESENT;
-       __set_pmd_pte(kpte, address, mk_pte(base, ref_prot));
+       __flush_tlb_all();
+
        base = NULL;
 
 out_unlock:
-       spin_unlock_irqrestore(&pgd_lock, flags);
-
+       /*
+        * If we dropped out via the lookup_address check under
+        * pgd_lock then stick the page back into the pool:
+        */
        if (base)
-               __free_pages(base, 0);
+               __free_page(base);
+       spin_unlock_irqrestore(&pgd_lock, flags);
 
        return 0;
 }
 
-static int __change_page_attr(unsigned long address, struct cpa_data *cpa)
+static int __cpa_process_fault(struct cpa_data *cpa, unsigned long vaddr,
+                              int primary)
 {
-       struct page *kpte_page;
-       int level, res;
-       pte_t *kpte;
+       /*
+        * Ignore all non primary paths.
+        */
+       if (!primary)
+               return 0;
+
+       /*
+        * Ignore the NULL PTE for kernel identity mapping, as it is expected
+        * to have holes.
+        * Also set numpages to '1' indicating that we processed cpa req for
+        * one virtual address page and its pfn. TBD: numpages can be set based
+        * on the initial value and the level returned by lookup_address().
+        */
+       if (within(vaddr, PAGE_OFFSET,
+                  PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT))) {
+               cpa->numpages = 1;
+               cpa->pfn = __pa(vaddr) >> PAGE_SHIFT;
+               return 0;
+       } else {
+               WARN(1, KERN_WARNING "CPA: called for zero pte. "
+                       "vaddr = %lx cpa->vaddr = %lx\n", vaddr,
+                       *cpa->vaddr);
 
+               return -EFAULT;
+       }
+}
+
+static int __change_page_attr(struct cpa_data *cpa, int primary)
+{
+       unsigned long address;
+       int do_split, err;
+       unsigned int level;
+       pte_t *kpte, old_pte;
+
+       if (cpa->flags & CPA_PAGES_ARRAY)
+               address = (unsigned long)page_address(cpa->pages[cpa->curpage]);
+       else if (cpa->flags & CPA_ARRAY)
+               address = cpa->vaddr[cpa->curpage];
+       else
+               address = *cpa->vaddr;
 repeat:
        kpte = lookup_address(address, &level);
        if (!kpte)
-               return -EINVAL;
+               return __cpa_process_fault(cpa, address, primary);
 
-       kpte_page = virt_to_page(kpte);
-       BUG_ON(PageLRU(kpte_page));
-       BUG_ON(PageCompound(kpte_page));
+       old_pte = *kpte;
+       if (!pte_val(old_pte))
+               return __cpa_process_fault(cpa, address, primary);
 
        if (level == PG_LEVEL_4K) {
-               pte_t new_pte, old_pte = *kpte;
+               pte_t new_pte;
                pgprot_t new_prot = pte_pgprot(old_pte);
-
-               if(!pte_val(old_pte)) {
-                       printk(KERN_WARNING "CPA: called for zero pte. "
-                              "vaddr = %lx cpa->vaddr = %lx\n", address,
-                               cpa->vaddr);
-                       WARN_ON(1);
-                       return -EINVAL;
-               }
+               unsigned long pfn = pte_pfn(old_pte);
 
                pgprot_val(new_prot) &= ~pgprot_val(cpa->mask_clr);
                pgprot_val(new_prot) |= pgprot_val(cpa->mask_set);
 
-               new_prot = static_protections(new_prot, address);
+               new_prot = static_protections(new_prot, address, pfn);
 
                /*
                 * We need to keep the pfn from the existing PTE,
                 * after all we're only going to change it's attributes
                 * not the memory it points to
                 */
-               new_pte = pfn_pte(pte_pfn(old_pte), canon_pgprot(new_prot));
-
+               new_pte = pfn_pte(pfn, canon_pgprot(new_prot));
+               cpa->pfn = pfn;
                /*
                 * Do we really change anything ?
                 */
                if (pte_val(old_pte) != pte_val(new_pte)) {
                        set_pte_atomic(kpte, new_pte);
-                       cpa->flushtlb = 1;
+                       cpa->flags |= CPA_FLUSHTLB;
                }
                cpa->numpages = 1;
                return 0;
@@ -457,90 +642,114 @@ repeat:
         * Check, whether we can keep the large page intact
         * and just change the pte:
         */
-       res = try_preserve_large_page(kpte, address, cpa);
-       if (res < 0)
-               return res;
-
+       do_split = try_preserve_large_page(kpte, address, cpa);
        /*
         * When the range fits into the existing large page,
         * return. cp->numpages and cpa->tlbflush have been updated in
         * try_large_page:
         */
-       if (res == CPA_NO_SPLIT)
-               return 0;
+       if (do_split <= 0)
+               return do_split;
 
        /*
         * We have to split the large page:
         */
-       res = split_large_page(kpte, address);
-       if (res)
-               return res;
-       cpa->flushtlb = 1;
-       goto repeat;
+       err = split_large_page(kpte, address);
+       if (!err) {
+               /*
+                * Do a global flush tlb after splitting the large page
+                * and before we do the actual change page attribute in the PTE.
+                *
+                * With out this, we violate the TLB application note, that says
+                * "The TLBs may contain both ordinary and large-page
+                *  translations for a 4-KByte range of linear addresses. This
+                *  may occur if software modifies the paging structures so that
+                *  the page size used for the address range changes. If the two
+                *  translations differ with respect to page frame or attributes
+                *  (e.g., permissions), processor behavior is undefined and may
+                *  be implementation-specific."
+                *
+                * We do this global tlb flush inside the cpa_lock, so that we
+                * don't allow any other cpu, with stale tlb entries change the
+                * page attribute in parallel, that also falls into the
+                * just split large page entry.
+                */
+               flush_tlb_all();
+               goto repeat;
+       }
+
+       return err;
 }
 
-/**
- * change_page_attr_addr - Change page table attributes in linear mapping
- * @address: Virtual address in linear mapping.
- * @prot:    New page table attribute (PAGE_*)
- *
- * Change page attributes of a page in the direct mapping. This is a variant
- * of change_page_attr() that also works on memory holes that do not have
- * mem_map entry (pfn_valid() is false).
- *
- * See change_page_attr() documentation for more details.
- *
- * Modules and drivers should use the set_memory_* APIs instead.
- */
+static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias);
 
-static int change_page_attr_addr(struct cpa_data *cpa)
+static int cpa_process_alias(struct cpa_data *cpa)
 {
-       int err;
-       unsigned long address = cpa->vaddr;
+       struct cpa_data alias_cpa;
+       int ret = 0;
+       unsigned long temp_cpa_vaddr, vaddr;
 
-#ifdef CONFIG_X86_64
-       unsigned long phys_addr = __pa(address);
+       if (cpa->pfn >= max_pfn_mapped)
+               return 0;
 
+#ifdef CONFIG_X86_64
+       if (cpa->pfn >= max_low_pfn_mapped && cpa->pfn < (1UL<<(32-PAGE_SHIFT)))
+               return 0;
+#endif
        /*
-        * If we are inside the high mapped kernel range, then we
-        * fixup the low mapping first. __va() returns the virtual
-        * address in the linear mapping:
+        * No need to redo, when the primary call touched the direct
+        * mapping already:
         */
-       if (within(address, HIGH_MAP_START, HIGH_MAP_END))
-               address = (unsigned long) __va(phys_addr);
-#endif
+       if (cpa->flags & CPA_PAGES_ARRAY)
+               vaddr = (unsigned long)page_address(cpa->pages[cpa->curpage]);
+       else if (cpa->flags & CPA_ARRAY)
+               vaddr = cpa->vaddr[cpa->curpage];
+       else
+               vaddr = *cpa->vaddr;
 
-       err = __change_page_attr(address, cpa);
-       if (err)
-               return err;
+       if (!(within(vaddr, PAGE_OFFSET,
+                   PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT)))) {
+
+               alias_cpa = *cpa;
+               temp_cpa_vaddr = (unsigned long) __va(cpa->pfn << PAGE_SHIFT);
+               alias_cpa.vaddr = &temp_cpa_vaddr;
+               alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY);
+
+
+               ret = __change_page_attr_set_clr(&alias_cpa, 0);
+       }
 
 #ifdef CONFIG_X86_64
+       if (ret)
+               return ret;
+       /*
+        * No need to redo, when the primary call touched the high
+        * mapping already:
+        */
+       if (within(vaddr, (unsigned long) _text, _brk_end))
+               return 0;
+
        /*
         * If the physical address is inside the kernel map, we need
         * to touch the high mapped kernel as well:
         */
-       if (within(phys_addr, 0, KERNEL_TEXT_SIZE)) {
-               /*
-                * Calc the high mapping address. See __phys_addr()
-                * for the non obvious details.
-                *
-                * Note that NX and other required permissions are
-                * checked in static_protections().
-                */
-               address = phys_addr + HIGH_MAP_START - phys_base;
+       if (!within(cpa->pfn, highmap_start_pfn(), highmap_end_pfn()))
+               return 0;
 
-               /*
-                * Our high aliases are imprecise, because we check
-                * everything between 0 and KERNEL_TEXT_SIZE, so do
-                * not propagate lookup failures back to users:
-                */
-               __change_page_attr(address, cpa);
-       }
+       alias_cpa = *cpa;
+       temp_cpa_vaddr = (cpa->pfn << PAGE_SHIFT) + __START_KERNEL_map - phys_base;
+       alias_cpa.vaddr = &temp_cpa_vaddr;
+       alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY);
+
+       /*
+        * The high mapping range is imprecise, so ignore the return value.
+        */
+       __change_page_attr_set_clr(&alias_cpa, 0);
 #endif
-       return err;
+       return ret;
 }
 
-static int __change_page_attr_set_clr(struct cpa_data *cpa)
+static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias)
 {
        int ret, numpages = cpa->numpages;
 
@@ -550,10 +759,24 @@ static int __change_page_attr_set_clr(struct cpa_data *cpa)
                 * preservation check.
                 */
                cpa->numpages = numpages;
-               ret = change_page_attr_addr(cpa);
+               /* for array changes, we can't use large page */
+               if (cpa->flags & (CPA_ARRAY | CPA_PAGES_ARRAY))
+                       cpa->numpages = 1;
+
+               if (!debug_pagealloc)
+                       spin_lock(&cpa_lock);
+               ret = __change_page_attr(cpa, checkalias);
+               if (!debug_pagealloc)
+                       spin_unlock(&cpa_lock);
                if (ret)
                        return ret;
 
+               if (checkalias) {
+                       ret = cpa_process_alias(cpa);
+                       if (ret)
+                               return ret;
+               }
+
                /*
                 * Adjust the number of pages with the result of the
                 * CPA operation. Either a large page has been
@@ -561,7 +784,11 @@ static int __change_page_attr_set_clr(struct cpa_data *cpa)
                 */
                BUG_ON(cpa->numpages > numpages);
                numpages -= cpa->numpages;
-               cpa->vaddr += cpa->numpages * PAGE_SIZE;
+               if (cpa->flags & (CPA_PAGES_ARRAY | CPA_ARRAY))
+                       cpa->curpage++;
+               else
+                       *cpa->vaddr += cpa->numpages * PAGE_SIZE;
+
        }
        return 0;
 }
@@ -572,11 +799,13 @@ static inline int cache_attr(pgprot_t attr)
                (_PAGE_PAT | _PAGE_PAT_LARGE | _PAGE_PWT | _PAGE_PCD);
 }
 
-static int change_page_attr_set_clr(unsigned long addr, int numpages,
-                                   pgprot_t mask_set, pgprot_t mask_clr)
+static int change_page_attr_set_clr(unsigned long *addr, int numpages,
+                                   pgprot_t mask_set, pgprot_t mask_clr,
+                                   int force_split, int in_flag,
+                                   struct page **pages)
 {
        struct cpa_data cpa;
-       int ret, cache;
+       int ret, cache, checkalias;
 
        /*
         * Check, if we are requested to change a not supported
@@ -584,22 +813,59 @@ 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 */
+       if (in_flag & CPA_ARRAY) {
+               int i;
+               for (i = 0; i < numpages; i++) {
+                       if (addr[i] & ~PAGE_MASK) {
+                               addr[i] &= PAGE_MASK;
+                               WARN_ON_ONCE(1);
+                       }
+               }
+       } else if (!(in_flag & CPA_PAGES_ARRAY)) {
+               /*
+                * in_flag of CPA_PAGES_ARRAY implies it is aligned.
+                * No need to cehck in that case
+                */
+               if (*addr & ~PAGE_MASK) {
+                       *addr &= PAGE_MASK;
+                       /*
+                        * People should not be passing in unaligned addresses:
+                        */
+                       WARN_ON_ONCE(1);
+               }
+       }
+
+       /* Must avoid aliasing mappings in the highmem code */
+       kmap_flush_unused();
+
+       vm_unmap_aliases();
+
        cpa.vaddr = addr;
+       cpa.pages = pages;
        cpa.numpages = numpages;
        cpa.mask_set = mask_set;
        cpa.mask_clr = mask_clr;
-       cpa.flushtlb = 0;
+       cpa.flags = 0;
+       cpa.curpage = 0;
+       cpa.force_split = force_split;
 
-       ret = __change_page_attr_set_clr(&cpa);
+       if (in_flag & (CPA_ARRAY | CPA_PAGES_ARRAY))
+               cpa.flags |= in_flag;
+
+       /* No alias checking for _NX bit modifications */
+       checkalias = (pgprot_val(mask_set) | pgprot_val(mask_clr)) != _PAGE_NX;
+
+       ret = __change_page_attr_set_clr(&cpa, checkalias);
 
        /*
         * Check whether we really changed something:
         */
-       if (!cpa.flushtlb)
-               return ret;
+       if (!(cpa.flags & CPA_FLUSHTLB))
+               goto out;
 
        /*
         * No need to flush, when we did not set any of the caching
@@ -613,65 +879,218 @@ static int change_page_attr_set_clr(unsigned long addr, int numpages,
         * error case we fall back to cpa_flush_all (which uses
         * wbindv):
         */
-       if (!ret && cpu_has_clflush)
-               cpa_flush_range(addr, numpages, cache);
-       else
+       if (!ret && cpu_has_clflush) {
+               if (cpa.flags & (CPA_PAGES_ARRAY | CPA_ARRAY)) {
+                       cpa_flush_array(addr, numpages, cache,
+                                       cpa.flags, pages);
+               } else
+                       cpa_flush_range(*addr, numpages, cache);
+       } else
                cpa_flush_all(cache);
 
+out:
        return ret;
 }
 
-static inline int change_page_attr_set(unsigned long addr, int numpages,
+static inline int change_page_attr_set(unsigned long *addr, int numpages,
+                                      pgprot_t mask, int array)
+{
+       return change_page_attr_set_clr(addr, numpages, mask, __pgprot(0), 0,
+               (array ? CPA_ARRAY : 0), NULL);
+}
+
+static inline int change_page_attr_clear(unsigned long *addr, int numpages,
+                                        pgprot_t mask, int array)
+{
+       return change_page_attr_set_clr(addr, numpages, __pgprot(0), mask, 0,
+               (array ? CPA_ARRAY : 0), NULL);
+}
+
+static inline int cpa_set_pages_array(struct page **pages, int numpages,
                                       pgprot_t mask)
 {
-       return change_page_attr_set_clr(addr, numpages, mask, __pgprot(0));
+       return change_page_attr_set_clr(NULL, numpages, mask, __pgprot(0), 0,
+               CPA_PAGES_ARRAY, pages);
 }
 
-static inline int change_page_attr_clear(unsigned long addr, int numpages,
+static inline int cpa_clear_pages_array(struct page **pages, int numpages,
                                         pgprot_t mask)
 {
-       return change_page_attr_set_clr(addr, numpages, __pgprot(0), mask);
+       return change_page_attr_set_clr(NULL, numpages, __pgprot(0), mask, 0,
+               CPA_PAGES_ARRAY, pages);
+}
+
+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_MINUS), 0);
 }
 
 int set_memory_uc(unsigned long addr, int numpages)
 {
-       return change_page_attr_set(addr, numpages,
-                                   __pgprot(_PAGE_PCD | _PAGE_PWT));
+       int ret;
+
+       /*
+        * for now UC MINUS. see comments in ioremap_nocache()
+        */
+       ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
+                           _PAGE_CACHE_UC_MINUS, NULL);
+       if (ret)
+               goto out_err;
+
+       ret = _set_memory_uc(addr, numpages);
+       if (ret)
+               goto out_free;
+
+       return 0;
+
+out_free:
+       free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
+out_err:
+       return ret;
 }
 EXPORT_SYMBOL(set_memory_uc);
 
+int set_memory_array_uc(unsigned long *addr, int addrinarray)
+{
+       int i, j;
+       int ret;
+
+       /*
+        * for now UC MINUS. see comments in ioremap_nocache()
+        */
+       for (i = 0; i < addrinarray; i++) {
+               ret = reserve_memtype(__pa(addr[i]), __pa(addr[i]) + PAGE_SIZE,
+                                       _PAGE_CACHE_UC_MINUS, NULL);
+               if (ret)
+                       goto out_free;
+       }
+
+       ret = change_page_attr_set(addr, addrinarray,
+                                   __pgprot(_PAGE_CACHE_UC_MINUS), 1);
+       if (ret)
+               goto out_free;
+
+       return 0;
+
+out_free:
+       for (j = 0; j < i; j++)
+               free_memtype(__pa(addr[j]), __pa(addr[j]) + PAGE_SIZE);
+
+       return ret;
+}
+EXPORT_SYMBOL(set_memory_array_uc);
+
+int _set_memory_wc(unsigned long addr, int numpages)
+{
+       int ret;
+       ret = change_page_attr_set(&addr, numpages,
+                                   __pgprot(_PAGE_CACHE_UC_MINUS), 0);
+
+       if (!ret) {
+               ret = change_page_attr_set(&addr, numpages,
+                                   __pgprot(_PAGE_CACHE_WC), 0);
+       }
+       return ret;
+}
+
+int set_memory_wc(unsigned long addr, int numpages)
+{
+       int ret;
+
+       if (!pat_enabled)
+               return set_memory_uc(addr, numpages);
+
+       ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
+               _PAGE_CACHE_WC, NULL);
+       if (ret)
+               goto out_err;
+
+       ret = _set_memory_wc(addr, numpages);
+       if (ret)
+               goto out_free;
+
+       return 0;
+
+out_free:
+       free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
+out_err:
+       return ret;
+}
+EXPORT_SYMBOL(set_memory_wc);
+
+int _set_memory_wb(unsigned long addr, int numpages)
+{
+       return change_page_attr_clear(&addr, numpages,
+                                     __pgprot(_PAGE_CACHE_MASK), 0);
+}
+
 int set_memory_wb(unsigned long addr, int numpages)
 {
-       return change_page_attr_clear(addr, numpages,
-                                     __pgprot(_PAGE_PCD | _PAGE_PWT));
+       int ret;
+
+       ret = _set_memory_wb(addr, numpages);
+       if (ret)
+               return ret;
+
+       free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
+       return 0;
 }
 EXPORT_SYMBOL(set_memory_wb);
 
+int set_memory_array_wb(unsigned long *addr, int addrinarray)
+{
+       int i;
+       int ret;
+
+       ret = change_page_attr_clear(addr, addrinarray,
+                                     __pgprot(_PAGE_CACHE_MASK), 1);
+       if (ret)
+               return ret;
+
+       for (i = 0; i < addrinarray; i++)
+               free_memtype(__pa(addr[i]), __pa(addr[i]) + PAGE_SIZE);
+
+       return 0;
+}
+EXPORT_SYMBOL(set_memory_array_wb);
+
 int set_memory_x(unsigned long addr, int numpages)
 {
-       return change_page_attr_clear(addr, numpages, __pgprot(_PAGE_NX));
+       return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_NX), 0);
 }
 EXPORT_SYMBOL(set_memory_x);
 
 int set_memory_nx(unsigned long addr, int numpages)
 {
-       return change_page_attr_set(addr, numpages, __pgprot(_PAGE_NX));
+       return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_NX), 0);
 }
 EXPORT_SYMBOL(set_memory_nx);
 
 int set_memory_ro(unsigned long addr, int numpages)
 {
-       return change_page_attr_clear(addr, numpages, __pgprot(_PAGE_RW));
+       return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_RW), 0);
 }
+EXPORT_SYMBOL_GPL(set_memory_ro);
 
 int set_memory_rw(unsigned long addr, int numpages)
 {
-       return change_page_attr_set(addr, numpages, __pgprot(_PAGE_RW));
+       return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_RW), 0);
 }
+EXPORT_SYMBOL_GPL(set_memory_rw);
 
 int set_memory_np(unsigned long addr, int numpages)
 {
-       return change_page_attr_clear(addr, numpages, __pgprot(_PAGE_PRESENT));
+       return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_PRESENT), 0);
+}
+
+int set_memory_4k(unsigned long addr, int numpages)
+{
+       return change_page_attr_set_clr(&addr, numpages, __pgprot(0),
+                                       __pgprot(0), 1, 0, NULL);
 }
 
 int set_pages_uc(struct page *page, int numpages)
@@ -682,6 +1101,35 @@ int set_pages_uc(struct page *page, int numpages)
 }
 EXPORT_SYMBOL(set_pages_uc);
 
+int set_pages_array_uc(struct page **pages, int addrinarray)
+{
+       unsigned long start;
+       unsigned long end;
+       int i;
+       int free_idx;
+
+       for (i = 0; i < addrinarray; i++) {
+               start = (unsigned long)page_address(pages[i]);
+               end = start + PAGE_SIZE;
+               if (reserve_memtype(start, end, _PAGE_CACHE_UC_MINUS, NULL))
+                       goto err_out;
+       }
+
+       if (cpa_set_pages_array(pages, addrinarray,
+                       __pgprot(_PAGE_CACHE_UC_MINUS)) == 0) {
+               return 0; /* Success */
+       }
+err_out:
+       free_idx = i;
+       for (i = 0; i < free_idx; i++) {
+               start = (unsigned long)page_address(pages[i]);
+               end = start + PAGE_SIZE;
+               free_memtype(start, end);
+       }
+       return -EINVAL;
+}
+EXPORT_SYMBOL(set_pages_array_uc);
+
 int set_pages_wb(struct page *page, int numpages)
 {
        unsigned long addr = (unsigned long)page_address(page);
@@ -690,6 +1138,28 @@ int set_pages_wb(struct page *page, int numpages)
 }
 EXPORT_SYMBOL(set_pages_wb);
 
+int set_pages_array_wb(struct page **pages, int addrinarray)
+{
+       int retval;
+       unsigned long start;
+       unsigned long end;
+       int i;
+
+       retval = cpa_clear_pages_array(pages, addrinarray,
+                       __pgprot(_PAGE_CACHE_MASK));
+       if (retval)
+               return retval;
+
+       for (i = 0; i < addrinarray; i++) {
+               start = (unsigned long)page_address(pages[i]);
+               end = start + PAGE_SIZE;
+               free_memtype(start, end);
+       }
+
+       return 0;
+}
+EXPORT_SYMBOL(set_pages_array_wb);
+
 int set_pages_x(struct page *page, int numpages)
 {
        unsigned long addr = (unsigned long)page_address(page);
@@ -724,22 +1194,38 @@ int set_pages_rw(struct page *page, int numpages)
 
 static int __set_pages_p(struct page *page, int numpages)
 {
-       struct cpa_data cpa = { .vaddr = (unsigned long) page_address(page),
+       unsigned long tempaddr = (unsigned long) page_address(page);
+       struct cpa_data cpa = { .vaddr = &tempaddr,
                                .numpages = numpages,
                                .mask_set = __pgprot(_PAGE_PRESENT | _PAGE_RW),
-                               .mask_clr = __pgprot(0)};
+                               .mask_clr = __pgprot(0),
+                               .flags = 0};
 
-       return __change_page_attr_set_clr(&cpa);
+       /*
+        * No alias checking needed for setting present flag. otherwise,
+        * we may need to break large pages for 64-bit kernel text
+        * mappings (this adds to complexity if we want to do this from
+        * atomic context especially). Let's keep it simple!
+        */
+       return __change_page_attr_set_clr(&cpa, 0);
 }
 
 static int __set_pages_np(struct page *page, int numpages)
 {
-       struct cpa_data cpa = { .vaddr = (unsigned long) page_address(page),
+       unsigned long tempaddr = (unsigned long) page_address(page);
+       struct cpa_data cpa = { .vaddr = &tempaddr,
                                .numpages = numpages,
                                .mask_set = __pgprot(0),
-                               .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW)};
+                               .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW),
+                               .flags = 0};
 
-       return __change_page_attr_set_clr(&cpa);
+       /*
+        * No alias checking needed for setting not present flag. otherwise,
+        * we may need to break large pages for 64-bit kernel text
+        * mappings (this adds to complexity if we want to do this from
+        * atomic context especially). Let's keep it simple!
+        */
+       return __change_page_attr_set_clr(&cpa, 0);
 }
 
 void kernel_map_pages(struct page *page, int numpages, int enable)
@@ -758,8 +1244,9 @@ void kernel_map_pages(struct page *page, int numpages, int enable)
                return;
 
        /*
-        * The return value is ignored - the calls cannot fail,
-        * large pages are disabled at boot time:
+        * The return value is ignored as the calls cannot fail.
+        * Large pages for identity mappings are not used at boot time
+        * and hence no memory allocations during large page split.
         */
        if (enable)
                __set_pages_p(page, numpages);
@@ -772,7 +1259,24 @@ void kernel_map_pages(struct page *page, int numpages, int enable)
         */
        __flush_tlb_all();
 }
-#endif
+
+#ifdef CONFIG_HIBERNATION
+
+bool kernel_page_present(struct page *page)
+{
+       unsigned int level;
+       pte_t *pte;
+
+       if (PageHighMem(page))
+               return false;
+
+       pte = lookup_address((unsigned long)page_address(page), &level);
+       return (pte_val(*pte) & _PAGE_PRESENT);
+}
+
+#endif /* CONFIG_HIBERNATION */
+
+#endif /* CONFIG_DEBUG_PAGEALLOC */
 
 /*
  * The testcases use internal knowledge of the implementation that shouldn't