1 files changed, 33 insertions, 141 deletions

diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 55c965b38c27..02d752460371 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -1054,7 +1054,7 @@ void xen_mm_pin_all(void)
  * that's before we have page structures to store the bits.  So do all
  * the book-keeping now.
  */
-static __init int xen_mark_pinned(struct mm_struct *mm, struct page *page,
+static int __init xen_mark_pinned(struct mm_struct *mm, struct page *page,
 				  enum pt_level level)
 {
 	SetPagePinned(page);
@@ -1187,7 +1187,7 @@ static void drop_other_mm_ref(void *info)
 
 	active_mm = percpu_read(cpu_tlbstate.active_mm);
 
-	if (active_mm == mm)
+	if (active_mm == mm && percpu_read(cpu_tlbstate.state) != TLBSTATE_OK)
 		leave_mm(smp_processor_id());
 
 	/* If this cpu still has a stale cr3 reference, then make sure
@@ -1271,13 +1271,27 @@ void xen_exit_mmap(struct mm_struct *mm)
 	spin_unlock(&mm->page_table_lock);
 }
 
-static __init void xen_pagetable_setup_start(pgd_t *base)
+static void __init xen_pagetable_setup_start(pgd_t *base)
 {
 }
 
+static __init void xen_mapping_pagetable_reserve(u64 start, u64 end)
+{
+	/* reserve the range used */
+	native_pagetable_reserve(start, end);
+
+	/* set as RW the rest */
+	printk(KERN_DEBUG "xen: setting RW the range %llx - %llx\n", end,
+			PFN_PHYS(pgt_buf_top));
+	while (end < PFN_PHYS(pgt_buf_top)) {
+		make_lowmem_page_readwrite(__va(end));
+		end += PAGE_SIZE;
+	}
+}
+
 static void xen_post_allocator_init(void);
 
-static __init void xen_pagetable_setup_done(pgd_t *base)
+static void __init xen_pagetable_setup_done(pgd_t *base)
 {
 	xen_setup_shared_info();
 	xen_post_allocator_init();
@@ -1463,119 +1477,6 @@ static int xen_pgd_alloc(struct mm_struct *mm)
 	return ret;
 }
 
-#ifdef CONFIG_X86_64
-static __initdata u64 __last_pgt_set_rw = 0;
-static __initdata u64 __pgt_buf_start = 0;
-static __initdata u64 __pgt_buf_end = 0;
-static __initdata u64 __pgt_buf_top = 0;
-/*
- * As a consequence of the commit:
- * 
- * commit 4b239f458c229de044d6905c2b0f9fe16ed9e01e
- * Author: Yinghai Lu <yinghai@kernel.org>
- * Date:   Fri Dec 17 16:58:28 2010 -0800
- * 
- *     x86-64, mm: Put early page table high
- * 
- * at some point init_memory_mapping is going to reach the pagetable pages
- * area and map those pages too (mapping them as normal memory that falls
- * in the range of addresses passed to init_memory_mapping as argument).
- * Some of those pages are already pagetable pages (they are in the range
- * pgt_buf_start-pgt_buf_end) therefore they are going to be mapped RO and
- * everything is fine.
- * Some of these pages are not pagetable pages yet (they fall in the range
- * pgt_buf_end-pgt_buf_top; for example the page at pgt_buf_end) so they
- * are going to be mapped RW.  When these pages become pagetable pages and
- * are hooked into the pagetable, xen will find that the guest has already
- * a RW mapping of them somewhere and fail the operation.
- * The reason Xen requires pagetables to be RO is that the hypervisor needs
- * to verify that the pagetables are valid before using them. The validation
- * operations are called "pinning".
- * 
- * In order to fix the issue we mark all the pages in the entire range
- * pgt_buf_start-pgt_buf_top as RO, however when the pagetable allocation
- * is completed only the range pgt_buf_start-pgt_buf_end is reserved by
- * init_memory_mapping. Hence the kernel is going to crash as soon as one
- * of the pages in the range pgt_buf_end-pgt_buf_top is reused (b/c those
- * ranges are RO).
- * 
- * For this reason, 'mark_rw_past_pgt' is introduced which is called _after_
- * the init_memory_mapping has completed (in a perfect world we would
- * call this function from init_memory_mapping, but lets ignore that).
- * 
- * Because we are called _after_ init_memory_mapping the pgt_buf_[start,
- * end,top] have all changed to new values (b/c init_memory_mapping
- * is called and setting up another new page-table). Hence, the first time
- * we enter this function, we save away the pgt_buf_start value and update
- * the pgt_buf_[end,top].
- * 
- * When we detect that the "old" pgt_buf_start through pgt_buf_end
- * PFNs have been reserved (so memblock_x86_reserve_range has been called),
- * we immediately set out to RW the "old" pgt_buf_end through pgt_buf_top.
- * 
- * And then we update those "old" pgt_buf_[end|top] with the new ones
- * so that we can redo this on the next pagetable.
- */
-static __init void mark_rw_past_pgt(void) {
-
-	if (pgt_buf_end > pgt_buf_start) {
-		u64 addr, size;
-
-		/* Save it away. */
-		if (!__pgt_buf_start) {
-			__pgt_buf_start = pgt_buf_start;
-			__pgt_buf_end = pgt_buf_end;
-			__pgt_buf_top = pgt_buf_top;
-			return;
-		}
-		/* If we get the range that starts at __pgt_buf_end that means
-		 * the range is reserved, and that in 'init_memory_mapping'
-		 * the 'memblock_x86_reserve_range' has been called with the
-		 * outdated __pgt_buf_start, __pgt_buf_end (the "new"
-		 * pgt_buf_[start|end|top] refer now to a new pagetable.
-		 * Note: we are called _after_ the pgt_buf_[..] have been
-		 * updated.*/
-
-		addr = memblock_x86_find_in_range_size(PFN_PHYS(__pgt_buf_start),
-						       &size, PAGE_SIZE);
-
-		/* Still not reserved, meaning 'memblock_x86_reserve_range'
-		 * hasn't been called yet. Update the _end and _top.*/
-		if (addr == PFN_PHYS(__pgt_buf_start)) {
-			__pgt_buf_end = pgt_buf_end;
-			__pgt_buf_top = pgt_buf_top;
-			return;
-		}
-
-		/* OK, the area is reserved, meaning it is time for us to
-		 * set RW for the old end->top PFNs. */
-
-		/* ..unless we had already done this. */
-		if (__pgt_buf_end == __last_pgt_set_rw)
-			return;
-
-		addr = PFN_PHYS(__pgt_buf_end);
-		
-		/* set as RW the rest */
-		printk(KERN_DEBUG "xen: setting RW the range %llx - %llx\n",
-			PFN_PHYS(__pgt_buf_end), PFN_PHYS(__pgt_buf_top));
-		
-		while (addr < PFN_PHYS(__pgt_buf_top)) {
-			make_lowmem_page_readwrite(__va(addr));
-			addr += PAGE_SIZE;
-		}
-		/* And update everything so that we are ready for the next
-		 * pagetable (the one created for regions past 4GB) */
-		__last_pgt_set_rw = __pgt_buf_end;
-		__pgt_buf_start = pgt_buf_start;
-		__pgt_buf_end = pgt_buf_end;
-		__pgt_buf_top = pgt_buf_top;
-	}
-	return;
-}
-#else
-static __init void mark_rw_past_pgt(void) { }
-#endif
 static void xen_pgd_free(struct mm_struct *mm, pgd_t *pgd)
 {
 #ifdef CONFIG_X86_64
@@ -1587,7 +1488,7 @@ static void xen_pgd_free(struct mm_struct *mm, pgd_t *pgd)
 }
 
 #ifdef CONFIG_X86_32
-static __init pte_t mask_rw_pte(pte_t *ptep, pte_t pte)
+static pte_t __init mask_rw_pte(pte_t *ptep, pte_t pte)
 {
 	/* If there's an existing pte, then don't allow _PAGE_RW to be set */
 	if (pte_val_ma(*ptep) & _PAGE_PRESENT)
@@ -1597,19 +1498,11 @@ static __init pte_t mask_rw_pte(pte_t *ptep, pte_t pte)
 	return pte;
 }
 #else /* CONFIG_X86_64 */
-static __init pte_t mask_rw_pte(pte_t *ptep, pte_t pte)
+static pte_t __init mask_rw_pte(pte_t *ptep, pte_t pte)
 {
 	unsigned long pfn = pte_pfn(pte);
 
 	/*
-	 * A bit of optimization. We do not need to call the workaround
-	 * when xen_set_pte_init is called with a PTE with 0 as PFN.
-	 * That is b/c the pagetable at that point are just being populated
-	 * with empty values and we can save some cycles by not calling
-	 * the 'memblock' code.*/
-	if (pfn)
-		mark_rw_past_pgt();
-	/*
 	 * If the new pfn is within the range of the newly allocated
 	 * kernel pagetable, and it isn't being mapped into an
 	 * early_ioremap fixmap slot as a freshly allocated page, make sure
@@ -1626,7 +1519,7 @@ static __init pte_t mask_rw_pte(pte_t *ptep, pte_t pte)
 
 /* Init-time set_pte while constructing initial pagetables, which
    doesn't allow RO pagetable pages to be remapped RW */
-static __init void xen_set_pte_init(pte_t *ptep, pte_t pte)
+static void __init xen_set_pte_init(pte_t *ptep, pte_t pte)
 {
 	pte = mask_rw_pte(ptep, pte);
 
@@ -1644,7 +1537,7 @@ static void pin_pagetable_pfn(unsigned cmd, unsigned long pfn)
 
 /* Early in boot, while setting up the initial pagetable, assume
    everything is pinned. */
-static __init void xen_alloc_pte_init(struct mm_struct *mm, unsigned long pfn)
+static void __init xen_alloc_pte_init(struct mm_struct *mm, unsigned long pfn)
 {
 #ifdef CONFIG_FLATMEM
 	BUG_ON(mem_map);	/* should only be used early */
@@ -1654,7 +1547,7 @@ static __init void xen_alloc_pte_init(struct mm_struct *mm, unsigned long pfn)
 }
 
 /* Used for pmd and pud */
-static __init void xen_alloc_pmd_init(struct mm_struct *mm, unsigned long pfn)
+static void __init xen_alloc_pmd_init(struct mm_struct *mm, unsigned long pfn)
 {
 #ifdef CONFIG_FLATMEM
 	BUG_ON(mem_map);	/* should only be used early */
@@ -1664,13 +1557,13 @@ static __init void xen_alloc_pmd_init(struct mm_struct *mm, unsigned long pfn)
 
 /* Early release_pte assumes that all pts are pinned, since there's
    only init_mm and anything attached to that is pinned. */
-static __init void xen_release_pte_init(unsigned long pfn)
+static void __init xen_release_pte_init(unsigned long pfn)
 {
 	pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, pfn);
 	make_lowmem_page_readwrite(__va(PFN_PHYS(pfn)));
 }
 
-static __init void xen_release_pmd_init(unsigned long pfn)
+static void __init xen_release_pmd_init(unsigned long pfn)
 {
 	make_lowmem_page_readwrite(__va(PFN_PHYS(pfn)));
 }
@@ -1796,7 +1689,7 @@ static void set_page_prot(void *addr, pgprot_t prot)
 		BUG();
 }
 
-static __init void xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn)
+static void __init xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn)
 {
 	unsigned pmdidx, pteidx;
 	unsigned ident_pte;
@@ -1879,7 +1772,7 @@ static void convert_pfn_mfn(void *v)
  * of the physical mapping once some sort of allocator has been set
  * up.
  */
-__init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd,
+pgd_t * __init xen_setup_kernel_pagetable(pgd_t *pgd,
 					 unsigned long max_pfn)
 {
 	pud_t *l3;
@@ -1950,7 +1843,7 @@ __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd,
 static RESERVE_BRK_ARRAY(pmd_t, initial_kernel_pmd, PTRS_PER_PMD);
 static RESERVE_BRK_ARRAY(pmd_t, swapper_kernel_pmd, PTRS_PER_PMD);
 
-static __init void xen_write_cr3_init(unsigned long cr3)
+static void __init xen_write_cr3_init(unsigned long cr3)
 {
 	unsigned long pfn = PFN_DOWN(__pa(swapper_pg_dir));
 
@@ -1987,7 +1880,7 @@ static __init void xen_write_cr3_init(unsigned long cr3)
 	pv_mmu_ops.write_cr3 = &xen_write_cr3;
 }
 
-__init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd,
+pgd_t * __init xen_setup_kernel_pagetable(pgd_t *pgd,
 					 unsigned long max_pfn)
 {
 	pmd_t *kernel_pmd;
@@ -2093,7 +1986,7 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot)
 #endif
 }
 
-__init void xen_ident_map_ISA(void)
+void __init xen_ident_map_ISA(void)
 {
 	unsigned long pa;
 
@@ -2116,10 +2009,8 @@ __init void xen_ident_map_ISA(void)
 	xen_flush_tlb();
 }
 
-static __init void xen_post_allocator_init(void)
+static void __init xen_post_allocator_init(void)
 {
-	mark_rw_past_pgt();
-
 #ifdef CONFIG_XEN_DEBUG
 	pv_mmu_ops.make_pte = PV_CALLEE_SAVE(xen_make_pte_debug);
 #endif
@@ -2155,7 +2046,7 @@ static void xen_leave_lazy_mmu(void)
 	preempt_enable();
 }
 
-static const struct pv_mmu_ops xen_mmu_ops __initdata = {
+static const struct pv_mmu_ops xen_mmu_ops __initconst = {
 	.read_cr2 = xen_read_cr2,
 	.write_cr2 = xen_write_cr2,
 
@@ -2228,6 +2119,7 @@ static const struct pv_mmu_ops xen_mmu_ops __initdata = {
 
 void __init xen_init_mmu_ops(void)
 {
+	x86_init.mapping.pagetable_reserve = xen_mapping_pagetable_reserve;
 	x86_init.paging.pagetable_setup_start = xen_pagetable_setup_start;
 	x86_init.paging.pagetable_setup_done = xen_pagetable_setup_done;
 	pv_mmu_ops = xen_mmu_ops;