Linux-libre 4.8.2-gnupck-4.8.2-gnu

11 files changed, 2225 insertions, 267 deletions

diff --git a/arch/s390/mm/dump_pagetables.c b/arch/s390/mm/dump_pagetables.c
index 8556d6be9..861880df1 100644
--- a/arch/s390/mm/dump_pagetables.c
+++ b/arch/s390/mm/dump_pagetables.c
@@ -157,7 +157,7 @@ static void walk_pud_level(struct seq_file *m, struct pg_state *st,
 		pud = pud_offset(pgd, addr);
 		if (!pud_none(*pud))
 			if (pud_large(*pud)) {
-				prot = pud_val(*pud) & _REGION3_ENTRY_RO;
+				prot = pud_val(*pud) & _REGION_ENTRY_PROTECT;
 				note_page(m, st, prot, 2);
 			} else
 				walk_pmd_level(m, st, pud, addr);
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 19288c1b3..a58bca62a 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -418,6 +418,8 @@ static inline int do_exception(struct pt_regs *regs, int access)
 		(struct gmap *) S390_lowcore.gmap : NULL;
 	if (gmap) {
 		current->thread.gmap_addr = address;
+		current->thread.gmap_write_flag = !!(flags & FAULT_FLAG_WRITE);
+		current->thread.gmap_int_code = regs->int_code & 0xffff;
 		address = __gmap_translate(gmap, address);
 		if (address == -EFAULT) {
 			fault = VM_FAULT_BADMAP;
@@ -456,7 +458,7 @@ retry:
 	 * make sure we exit gracefully rather than endlessly redo
 	 * the fault.
 	 */
-	fault = handle_mm_fault(mm, vma, address, flags);
+	fault = handle_mm_fault(vma, address, flags);
 	/* No reason to continue if interrupted by SIGKILL. */
 	if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current)) {
 		fault = VM_FAULT_SIGNAL;
@@ -624,7 +626,7 @@ void pfault_fini(void)
 	diag_stat_inc(DIAG_STAT_X258);
 	asm volatile(
 		"	diag	%0,0,0x258\n"
-		"0:\n"
+		"0:	nopr	%%r7\n"
 		EX_TABLE(0b,0b)
 		: : "a" (&refbk), "m" (refbk) : "cc");
 }
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index 313c3b8cf..2ce6bb3ba 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -20,14 +20,16 @@
 #include <asm/gmap.h>
 #include <asm/tlb.h>
 
+#define GMAP_SHADOW_FAKE_TABLE 1ULL
+
 /**
- * gmap_alloc - allocate a guest address space
+ * gmap_alloc - allocate and initialize a guest address space
  * @mm: pointer to the parent mm_struct
  * @limit: maximum address of the gmap address space
  *
  * Returns a guest address space structure.
  */
-struct gmap *gmap_alloc(struct mm_struct *mm, unsigned long limit)
+static struct gmap *gmap_alloc(unsigned long limit)
 {
 	struct gmap *gmap;
 	struct page *page;
@@ -55,10 +57,14 @@ struct gmap *gmap_alloc(struct mm_struct *mm, unsigned long limit)
 	if (!gmap)
 		goto out;
 	INIT_LIST_HEAD(&gmap->crst_list);
+	INIT_LIST_HEAD(&gmap->children);
+	INIT_LIST_HEAD(&gmap->pt_list);
 	INIT_RADIX_TREE(&gmap->guest_to_host, GFP_KERNEL);
 	INIT_RADIX_TREE(&gmap->host_to_guest, GFP_ATOMIC);
+	INIT_RADIX_TREE(&gmap->host_to_rmap, GFP_ATOMIC);
 	spin_lock_init(&gmap->guest_table_lock);
-	gmap->mm = mm;
+	spin_lock_init(&gmap->shadow_lock);
+	atomic_set(&gmap->ref_count, 1);
 	page = alloc_pages(GFP_KERNEL, 2);
 	if (!page)
 		goto out_free;
@@ -70,9 +76,6 @@ struct gmap *gmap_alloc(struct mm_struct *mm, unsigned long limit)
 	gmap->asce = atype | _ASCE_TABLE_LENGTH |
 		_ASCE_USER_BITS | __pa(table);
 	gmap->asce_end = limit;
-	down_write(&mm->mmap_sem);
-	list_add(&gmap->list, &mm->context.gmap_list);
-	up_write(&mm->mmap_sem);
 	return gmap;
 
 out_free:
@@ -80,7 +83,28 @@ out_free:
 out:
 	return NULL;
 }
-EXPORT_SYMBOL_GPL(gmap_alloc);
+
+/**
+ * gmap_create - create a guest address space
+ * @mm: pointer to the parent mm_struct
+ * @limit: maximum size of the gmap address space
+ *
+ * Returns a guest address space structure.
+ */
+struct gmap *gmap_create(struct mm_struct *mm, unsigned long limit)
+{
+	struct gmap *gmap;
+
+	gmap = gmap_alloc(limit);
+	if (!gmap)
+		return NULL;
+	gmap->mm = mm;
+	spin_lock(&mm->context.gmap_lock);
+	list_add_rcu(&gmap->list, &mm->context.gmap_list);
+	spin_unlock(&mm->context.gmap_lock);
+	return gmap;
+}
+EXPORT_SYMBOL_GPL(gmap_create);
 
 static void gmap_flush_tlb(struct gmap *gmap)
 {
@@ -114,31 +138,117 @@ static void gmap_radix_tree_free(struct radix_tree_root *root)
 	} while (nr > 0);
 }
 
+static void gmap_rmap_radix_tree_free(struct radix_tree_root *root)
+{
+	struct gmap_rmap *rmap, *rnext, *head;
+	struct radix_tree_iter iter;
+	unsigned long indices[16];
+	unsigned long index;
+	void **slot;
+	int i, nr;
+
+	/* A radix tree is freed by deleting all of its entries */
+	index = 0;
+	do {
+		nr = 0;
+		radix_tree_for_each_slot(slot, root, &iter, index) {
+			indices[nr] = iter.index;
+			if (++nr == 16)
+				break;
+		}
+		for (i = 0; i < nr; i++) {
+			index = indices[i];
+			head = radix_tree_delete(root, index);
+			gmap_for_each_rmap_safe(rmap, rnext, head)
+				kfree(rmap);
+		}
+	} while (nr > 0);
+}
+
 /**
  * gmap_free - free a guest address space
  * @gmap: pointer to the guest address space structure
+ *
+ * No locks required. There are no references to this gmap anymore.
  */
-void gmap_free(struct gmap *gmap)
+static void gmap_free(struct gmap *gmap)
 {
 	struct page *page, *next;
 
-	/* Flush tlb. */
-	if (MACHINE_HAS_IDTE)
-		__tlb_flush_idte(gmap->asce);
-	else
-		__tlb_flush_global();
-
+	/* Flush tlb of all gmaps (if not already done for shadows) */
+	if (!(gmap_is_shadow(gmap) && gmap->removed))
+		gmap_flush_tlb(gmap);
 	/* Free all segment & region tables. */
 	list_for_each_entry_safe(page, next, &gmap->crst_list, lru)
 		__free_pages(page, 2);
 	gmap_radix_tree_free(&gmap->guest_to_host);
 	gmap_radix_tree_free(&gmap->host_to_guest);
-	down_write(&gmap->mm->mmap_sem);
-	list_del(&gmap->list);
-	up_write(&gmap->mm->mmap_sem);
+
+	/* Free additional data for a shadow gmap */
+	if (gmap_is_shadow(gmap)) {
+		/* Free all page tables. */
+		list_for_each_entry_safe(page, next, &gmap->pt_list, lru)
+			page_table_free_pgste(page);
+		gmap_rmap_radix_tree_free(&gmap->host_to_rmap);
+		/* Release reference to the parent */
+		gmap_put(gmap->parent);
+	}
+
 	kfree(gmap);
 }
-EXPORT_SYMBOL_GPL(gmap_free);
+
+/**
+ * gmap_get - increase reference counter for guest address space
+ * @gmap: pointer to the guest address space structure
+ *
+ * Returns the gmap pointer
+ */
+struct gmap *gmap_get(struct gmap *gmap)
+{
+	atomic_inc(&gmap->ref_count);
+	return gmap;
+}
+EXPORT_SYMBOL_GPL(gmap_get);
+
+/**
+ * gmap_put - decrease reference counter for guest address space
+ * @gmap: pointer to the guest address space structure
+ *
+ * If the reference counter reaches zero the guest address space is freed.
+ */
+void gmap_put(struct gmap *gmap)
+{
+	if (atomic_dec_return(&gmap->ref_count) == 0)
+		gmap_free(gmap);
+}
+EXPORT_SYMBOL_GPL(gmap_put);
+
+/**
+ * gmap_remove - remove a guest address space but do not free it yet
+ * @gmap: pointer to the guest address space structure
+ */
+void gmap_remove(struct gmap *gmap)
+{
+	struct gmap *sg, *next;
+
+	/* Remove all shadow gmaps linked to this gmap */
+	if (!list_empty(&gmap->children)) {
+		spin_lock(&gmap->shadow_lock);
+		list_for_each_entry_safe(sg, next, &gmap->children, list) {
+			list_del(&sg->list);
+			gmap_put(sg);
+		}
+		spin_unlock(&gmap->shadow_lock);
+	}
+	/* Remove gmap from the pre-mm list */
+	spin_lock(&gmap->mm->context.gmap_lock);
+	list_del_rcu(&gmap->list);
+	spin_unlock(&gmap->mm->context.gmap_lock);
+	synchronize_rcu();
+	/* Put reference */
+	gmap_put(gmap);
+}
+EXPORT_SYMBOL_GPL(gmap_remove);
 
 /**
  * gmap_enable - switch primary space to the guest address space
@@ -160,6 +270,17 @@ void gmap_disable(struct gmap *gmap)
 }
 EXPORT_SYMBOL_GPL(gmap_disable);
 
+/**
+ * gmap_get_enabled - get a pointer to the currently enabled gmap
+ *
+ * Returns a pointer to the currently enabled gmap. 0 if none is enabled.
+ */
+struct gmap *gmap_get_enabled(void)
+{
+	return (struct gmap *) S390_lowcore.gmap;
+}
+EXPORT_SYMBOL_GPL(gmap_get_enabled);
+
 /*
  * gmap_alloc_table is assumed to be called with mmap_sem held
  */
@@ -175,7 +296,7 @@ static int gmap_alloc_table(struct gmap *gmap, unsigned long *table,
 		return -ENOMEM;
 	new = (unsigned long *) page_to_phys(page);
 	crst_table_init(new, init);
-	spin_lock(&gmap->mm->page_table_lock);
+	spin_lock(&gmap->guest_table_lock);
 	if (*table & _REGION_ENTRY_INVALID) {
 		list_add(&page->lru, &gmap->crst_list);
 		*table = (unsigned long) new | _REGION_ENTRY_LENGTH |
@@ -183,7 +304,7 @@ static int gmap_alloc_table(struct gmap *gmap, unsigned long *table,
 		page->index = gaddr;
 		page = NULL;
 	}
-	spin_unlock(&gmap->mm->page_table_lock);
+	spin_unlock(&gmap->guest_table_lock);
 	if (page)
 		__free_pages(page, 2);
 	return 0;
@@ -219,6 +340,7 @@ static int __gmap_unlink_by_vmaddr(struct gmap *gmap, unsigned long vmaddr)
 	unsigned long *entry;
 	int flush = 0;
 
+	BUG_ON(gmap_is_shadow(gmap));
 	spin_lock(&gmap->guest_table_lock);
 	entry = radix_tree_delete(&gmap->host_to_guest, vmaddr >> PMD_SHIFT);
 	if (entry) {
@@ -258,6 +380,7 @@ int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len)
 	unsigned long off;
 	int flush;
 
+	BUG_ON(gmap_is_shadow(gmap));
 	if ((to | len) & (PMD_SIZE - 1))
 		return -EINVAL;
 	if (len == 0 || to + len < to)
@@ -289,6 +412,7 @@ int gmap_map_segment(struct gmap *gmap, unsigned long from,
 	unsigned long off;
 	int flush;
 
+	BUG_ON(gmap_is_shadow(gmap));
 	if ((from | to | len) & (PMD_SIZE - 1))
 		return -EINVAL;
 	if (len == 0 || from + len < from || to + len < to ||
@@ -326,6 +450,8 @@ EXPORT_SYMBOL_GPL(gmap_map_segment);
  * This function does not establish potentially missing page table entries.
  * The mmap_sem of the mm that belongs to the address space must be held
  * when this function gets called.
+ *
+ * Note: Can also be called for shadow gmaps.
  */
 unsigned long __gmap_translate(struct gmap *gmap, unsigned long gaddr)
 {
@@ -333,6 +459,7 @@ unsigned long __gmap_translate(struct gmap *gmap, unsigned long gaddr)
 
 	vmaddr = (unsigned long)
 		radix_tree_lookup(&gmap->guest_to_host, gaddr >> PMD_SHIFT);
+	/* Note: guest_to_host is empty for a shadow gmap */
 	return vmaddr ? (vmaddr | (gaddr & ~PMD_MASK)) : -EFAULT;
 }
 EXPORT_SYMBOL_GPL(__gmap_translate);
@@ -369,11 +496,13 @@ void gmap_unlink(struct mm_struct *mm, unsigned long *table,
 	struct gmap *gmap;
 	int flush;
 
-	list_for_each_entry(gmap, &mm->context.gmap_list, list) {
+	rcu_read_lock();
+	list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) {
 		flush = __gmap_unlink_by_vmaddr(gmap, vmaddr);
 		if (flush)
 			gmap_flush_tlb(gmap);
 	}
+	rcu_read_unlock();
 }
 
 /**
@@ -397,6 +526,7 @@ int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr)
 	pmd_t *pmd;
 	int rc;
 
+	BUG_ON(gmap_is_shadow(gmap));
 	/* Create higher level tables in the gmap page table */
 	table = gmap->table;
 	if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION1) {
@@ -430,6 +560,9 @@ int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr)
 	VM_BUG_ON(pgd_none(*pgd));
 	pud = pud_offset(pgd, vmaddr);
 	VM_BUG_ON(pud_none(*pud));
+	/* large puds cannot yet be handled */
+	if (pud_large(*pud))
+		return -EFAULT;
 	pmd = pmd_offset(pud, vmaddr);
 	VM_BUG_ON(pmd_none(*pmd));
 	/* large pmds cannot yet be handled */
@@ -549,116 +682,1412 @@ static LIST_HEAD(gmap_notifier_list);
 static DEFINE_SPINLOCK(gmap_notifier_lock);
 
 /**
- * gmap_register_ipte_notifier - register a pte invalidation callback
+ * gmap_register_pte_notifier - register a pte invalidation callback
  * @nb: pointer to the gmap notifier block
  */
-void gmap_register_ipte_notifier(struct gmap_notifier *nb)
+void gmap_register_pte_notifier(struct gmap_notifier *nb)
 {
 	spin_lock(&gmap_notifier_lock);
-	list_add(&nb->list, &gmap_notifier_list);
+	list_add_rcu(&nb->list, &gmap_notifier_list);
 	spin_unlock(&gmap_notifier_lock);
 }
-EXPORT_SYMBOL_GPL(gmap_register_ipte_notifier);
+EXPORT_SYMBOL_GPL(gmap_register_pte_notifier);
 
 /**
- * gmap_unregister_ipte_notifier - remove a pte invalidation callback
+ * gmap_unregister_pte_notifier - remove a pte invalidation callback
  * @nb: pointer to the gmap notifier block
  */
-void gmap_unregister_ipte_notifier(struct gmap_notifier *nb)
+void gmap_unregister_pte_notifier(struct gmap_notifier *nb)
 {
 	spin_lock(&gmap_notifier_lock);
-	list_del_init(&nb->list);
+	list_del_rcu(&nb->list);
 	spin_unlock(&gmap_notifier_lock);
+	synchronize_rcu();
+}
+EXPORT_SYMBOL_GPL(gmap_unregister_pte_notifier);
+
+/**
+ * gmap_call_notifier - call all registered invalidation callbacks
+ * @gmap: pointer to guest mapping meta data structure
+ * @start: start virtual address in the guest address space
+ * @end: end virtual address in the guest address space
+ */
+static void gmap_call_notifier(struct gmap *gmap, unsigned long start,
+			       unsigned long end)
+{
+	struct gmap_notifier *nb;
+
+	list_for_each_entry(nb, &gmap_notifier_list, list)
+		nb->notifier_call(gmap, start, end);
+}
+
+/**
+ * gmap_table_walk - walk the gmap page tables
+ * @gmap: pointer to guest mapping meta data structure
+ * @gaddr: virtual address in the guest address space
+ * @level: page table level to stop at
+ *
+ * Returns a table entry pointer for the given guest address and @level
+ * @level=0 : returns a pointer to a page table table entry (or NULL)
+ * @level=1 : returns a pointer to a segment table entry (or NULL)
+ * @level=2 : returns a pointer to a region-3 table entry (or NULL)
+ * @level=3 : returns a pointer to a region-2 table entry (or NULL)
+ * @level=4 : returns a pointer to a region-1 table entry (or NULL)
+ *
+ * Returns NULL if the gmap page tables could not be walked to the
+ * requested level.
+ *
+ * Note: Can also be called for shadow gmaps.
+ */
+static inline unsigned long *gmap_table_walk(struct gmap *gmap,
+					     unsigned long gaddr, int level)
+{
+	unsigned long *table;
+
+	if ((gmap->asce & _ASCE_TYPE_MASK) + 4 < (level * 4))
+		return NULL;
+	if (gmap_is_shadow(gmap) && gmap->removed)
+		return NULL;
+	if (gaddr & (-1UL << (31 + ((gmap->asce & _ASCE_TYPE_MASK) >> 2)*11)))
+		return NULL;
+	table = gmap->table;
+	switch (gmap->asce & _ASCE_TYPE_MASK) {
+	case _ASCE_TYPE_REGION1:
+		table += (gaddr >> 53) & 0x7ff;
+		if (level == 4)
+			break;
+		if (*table & _REGION_ENTRY_INVALID)
+			return NULL;
+		table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
+		/* Fallthrough */
+	case _ASCE_TYPE_REGION2:
+		table += (gaddr >> 42) & 0x7ff;
+		if (level == 3)
+			break;
+		if (*table & _REGION_ENTRY_INVALID)
+			return NULL;
+		table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
+		/* Fallthrough */
+	case _ASCE_TYPE_REGION3:
+		table += (gaddr >> 31) & 0x7ff;
+		if (level == 2)
+			break;
+		if (*table & _REGION_ENTRY_INVALID)
+			return NULL;
+		table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
+		/* Fallthrough */
+	case _ASCE_TYPE_SEGMENT:
+		table += (gaddr >> 20) & 0x7ff;
+		if (level == 1)
+			break;
+		if (*table & _REGION_ENTRY_INVALID)
+			return NULL;
+		table = (unsigned long *)(*table & _SEGMENT_ENTRY_ORIGIN);
+		table += (gaddr >> 12) & 0xff;
+	}
+	return table;
+}
+
+/**
+ * gmap_pte_op_walk - walk the gmap page table, get the page table lock
+ *		      and return the pte pointer
+ * @gmap: pointer to guest mapping meta data structure
+ * @gaddr: virtual address in the guest address space
+ * @ptl: pointer to the spinlock pointer
+ *
+ * Returns a pointer to the locked pte for a guest address, or NULL
+ *
+ * Note: Can also be called for shadow gmaps.
+ */
+static pte_t *gmap_pte_op_walk(struct gmap *gmap, unsigned long gaddr,
+			       spinlock_t **ptl)
+{
+	unsigned long *table;
+
+	if (gmap_is_shadow(gmap))
+		spin_lock(&gmap->guest_table_lock);
+	/* Walk the gmap page table, lock and get pte pointer */
+	table = gmap_table_walk(gmap, gaddr, 1); /* get segment pointer */
+	if (!table || *table & _SEGMENT_ENTRY_INVALID) {
+		if (gmap_is_shadow(gmap))
+			spin_unlock(&gmap->guest_table_lock);
+		return NULL;
+	}
+	if (gmap_is_shadow(gmap)) {
+		*ptl = &gmap->guest_table_lock;
+		return pte_offset_map((pmd_t *) table, gaddr);
+	}
+	return pte_alloc_map_lock(gmap->mm, (pmd_t *) table, gaddr, ptl);
+}
+
+/**
+ * gmap_pte_op_fixup - force a page in and connect the gmap page table
+ * @gmap: pointer to guest mapping meta data structure
+ * @gaddr: virtual address in the guest address space
+ * @vmaddr: address in the host process address space
+ * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE
+ *
+ * Returns 0 if the caller can retry __gmap_translate (might fail again),
+ * -ENOMEM if out of memory and -EFAULT if anything goes wrong while fixing
+ * up or connecting the gmap page table.
+ */
+static int gmap_pte_op_fixup(struct gmap *gmap, unsigned long gaddr,
+			     unsigned long vmaddr, int prot)
+{
+	struct mm_struct *mm = gmap->mm;
+	unsigned int fault_flags;
+	bool unlocked = false;
+
+	BUG_ON(gmap_is_shadow(gmap));
+	fault_flags = (prot == PROT_WRITE) ? FAULT_FLAG_WRITE : 0;
+	if (fixup_user_fault(current, mm, vmaddr, fault_flags, &unlocked))
+		return -EFAULT;
+	if (unlocked)
+		/* lost mmap_sem, caller has to retry __gmap_translate */
+		return 0;
+	/* Connect the page tables */
+	return __gmap_link(gmap, gaddr, vmaddr);
 }
-EXPORT_SYMBOL_GPL(gmap_unregister_ipte_notifier);
 
 /**
- * gmap_ipte_notify - mark a range of ptes for invalidation notification
+ * gmap_pte_op_end - release the page table lock
+ * @ptl: pointer to the spinlock pointer
+ */
+static void gmap_pte_op_end(spinlock_t *ptl)
+{
+	spin_unlock(ptl);
+}
+
+/*
+ * gmap_protect_range - remove access rights to memory and set pgste bits
  * @gmap: pointer to guest mapping meta data structure
  * @gaddr: virtual address in the guest address space
  * @len: size of area
+ * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE
+ * @bits: pgste notification bits to set
+ *
+ * Returns 0 if successfully protected, -ENOMEM if out of memory and
+ * -EFAULT if gaddr is invalid (or mapping for shadows is missing).
  *
- * Returns 0 if for each page in the given range a gmap mapping exists and
- * the invalidation notification could be set. If the gmap mapping is missing
- * for one or more pages -EFAULT is returned. If no memory could be allocated
- * -ENOMEM is returned. This function establishes missing page table entries.
+ * Called with sg->mm->mmap_sem in read.
+ *
+ * Note: Can also be called for shadow gmaps.
  */
-int gmap_ipte_notify(struct gmap *gmap, unsigned long gaddr, unsigned long len)
+static int gmap_protect_range(struct gmap *gmap, unsigned long gaddr,
+			      unsigned long len, int prot, unsigned long bits)
 {
-	unsigned long addr;
+	unsigned long vmaddr;
 	spinlock_t *ptl;
 	pte_t *ptep;
-	bool unlocked;
-	int rc = 0;
+	int rc;
+
+	while (len) {
+		rc = -EAGAIN;
+		ptep = gmap_pte_op_walk(gmap, gaddr, &ptl);
+		if (ptep) {
+			rc = ptep_force_prot(gmap->mm, gaddr, ptep, prot, bits);
+			gmap_pte_op_end(ptl);
+		}
+		if (rc) {
+			vmaddr = __gmap_translate(gmap, gaddr);
+			if (IS_ERR_VALUE(vmaddr))
+				return vmaddr;
+			rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr, prot);
+			if (rc)
+				return rc;
+			continue;
+		}
+		gaddr += PAGE_SIZE;
+		len -= PAGE_SIZE;
+	}
+	return 0;
+}
 
-	if ((gaddr & ~PAGE_MASK) || (len & ~PAGE_MASK))
+/**
+ * gmap_mprotect_notify - change access rights for a range of ptes and
+ *                        call the notifier if any pte changes again
+ * @gmap: pointer to guest mapping meta data structure
+ * @gaddr: virtual address in the guest address space
+ * @len: size of area
+ * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE
+ *
+ * Returns 0 if for each page in the given range a gmap mapping exists,
+ * the new access rights could be set and the notifier could be armed.
+ * If the gmap mapping is missing for one or more pages -EFAULT is
+ * returned. If no memory could be allocated -ENOMEM is returned.
+ * This function establishes missing page table entries.
+ */
+int gmap_mprotect_notify(struct gmap *gmap, unsigned long gaddr,
+			 unsigned long len, int prot)
+{
+	int rc;
+
+	if ((gaddr & ~PAGE_MASK) || (len & ~PAGE_MASK) || gmap_is_shadow(gmap))
+		return -EINVAL;
+	if (!MACHINE_HAS_ESOP && prot == PROT_READ)
 		return -EINVAL;
 	down_read(&gmap->mm->mmap_sem);
-	while (len) {
-		unlocked = false;
-		/* Convert gmap address and connect the page tables */
-		addr = __gmap_translate(gmap, gaddr);
-		if (IS_ERR_VALUE(addr)) {
-			rc = addr;
+	rc = gmap_protect_range(gmap, gaddr, len, prot, PGSTE_IN_BIT);
+	up_read(&gmap->mm->mmap_sem);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(gmap_mprotect_notify);
+
+/**
+ * gmap_read_table - get an unsigned long value from a guest page table using
+ *                   absolute addressing, without marking the page referenced.
+ * @gmap: pointer to guest mapping meta data structure
+ * @gaddr: virtual address in the guest address space
+ * @val: pointer to the unsigned long value to return
+ *
+ * Returns 0 if the value was read, -ENOMEM if out of memory and -EFAULT
+ * if reading using the virtual address failed.
+ *
+ * Called with gmap->mm->mmap_sem in read.
+ */
+int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val)
+{
+	unsigned long address, vmaddr;
+	spinlock_t *ptl;
+	pte_t *ptep, pte;
+	int rc;
+
+	while (1) {
+		rc = -EAGAIN;
+		ptep = gmap_pte_op_walk(gmap, gaddr, &ptl);
+		if (ptep) {
+			pte = *ptep;
+			if (pte_present(pte) && (pte_val(pte) & _PAGE_READ)) {
+				address = pte_val(pte) & PAGE_MASK;
+				address += gaddr & ~PAGE_MASK;
+				*val = *(unsigned long *) address;
+				pte_val(*ptep) |= _PAGE_YOUNG;
+				/* Do *NOT* clear the _PAGE_INVALID bit! */
+				rc = 0;
+			}
+			gmap_pte_op_end(ptl);
+		}
+		if (!rc)
+			break;
+		vmaddr = __gmap_translate(gmap, gaddr);
+		if (IS_ERR_VALUE(vmaddr)) {
+			rc = vmaddr;
 			break;
 		}
-		/* Get the page mapped */
-		if (fixup_user_fault(current, gmap->mm, addr, FAULT_FLAG_WRITE,
-				     &unlocked)) {
-			rc = -EFAULT;
+		rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr, PROT_READ);
+		if (rc)
 			break;
+	}
+	return rc;
+}
+EXPORT_SYMBOL_GPL(gmap_read_table);
+
+/**
+ * gmap_insert_rmap - add a rmap to the host_to_rmap radix tree
+ * @sg: pointer to the shadow guest address space structure
+ * @vmaddr: vm address associated with the rmap
+ * @rmap: pointer to the rmap structure
+ *
+ * Called with the sg->guest_table_lock
+ */
+static inline void gmap_insert_rmap(struct gmap *sg, unsigned long vmaddr,
+				    struct gmap_rmap *rmap)
+{
+	void **slot;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	slot = radix_tree_lookup_slot(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT);
+	if (slot) {
+		rmap->next = radix_tree_deref_slot_protected(slot,
+							&sg->guest_table_lock);
+		radix_tree_replace_slot(slot, rmap);
+	} else {
+		rmap->next = NULL;
+		radix_tree_insert(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT,
+				  rmap);
+	}
+}
+
+/**
+ * gmap_protect_rmap - modify access rights to memory and create an rmap
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow gmap
+ * @paddr: address in the parent guest address space
+ * @len: length of the memory area to protect
+ * @prot: indicates access rights: none, read-only or read-write
+ *
+ * Returns 0 if successfully protected and the rmap was created, -ENOMEM
+ * if out of memory and -EFAULT if paddr is invalid.
+ */
+static int gmap_protect_rmap(struct gmap *sg, unsigned long raddr,
+			     unsigned long paddr, unsigned long len, int prot)
+{
+	struct gmap *parent;
+	struct gmap_rmap *rmap;
+	unsigned long vmaddr;
+	spinlock_t *ptl;
+	pte_t *ptep;
+	int rc;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	parent = sg->parent;
+	while (len) {
+		vmaddr = __gmap_translate(parent, paddr);
+		if (IS_ERR_VALUE(vmaddr))
+			return vmaddr;
+		rmap = kzalloc(sizeof(*rmap), GFP_KERNEL);
+		if (!rmap)
+			return -ENOMEM;
+		rmap->raddr = raddr;
+		rc = radix_tree_preload(GFP_KERNEL);
+		if (rc) {
+			kfree(rmap);
+			return rc;
 		}
-		/* While trying to map mmap_sem got unlocked. Let us retry */
-		if (unlocked)
+		rc = -EAGAIN;
+		ptep = gmap_pte_op_walk(parent, paddr, &ptl);
+		if (ptep) {
+			spin_lock(&sg->guest_table_lock);
+			rc = ptep_force_prot(parent->mm, paddr, ptep, prot,
+					     PGSTE_VSIE_BIT);
+			if (!rc)
+				gmap_insert_rmap(sg, vmaddr, rmap);
+			spin_unlock(&sg->guest_table_lock);
+			gmap_pte_op_end(ptl);
+		}
+		radix_tree_preload_end();
+		if (rc) {
+			kfree(rmap);
+			rc = gmap_pte_op_fixup(parent, paddr, vmaddr, prot);
+			if (rc)
+				return rc;
+			continue;
+		}
+		paddr += PAGE_SIZE;
+		len -= PAGE_SIZE;
+	}
+	return 0;
+}
+
+#define _SHADOW_RMAP_MASK	0x7
+#define _SHADOW_RMAP_REGION1	0x5
+#define _SHADOW_RMAP_REGION2	0x4
+#define _SHADOW_RMAP_REGION3	0x3
+#define _SHADOW_RMAP_SEGMENT	0x2
+#define _SHADOW_RMAP_PGTABLE	0x1
+
+/**
+ * gmap_idte_one - invalidate a single region or segment table entry
+ * @asce: region or segment table *origin* + table-type bits
+ * @vaddr: virtual address to identify the table entry to flush
+ *
+ * The invalid bit of a single region or segment table entry is set
+ * and the associated TLB entries depending on the entry are flushed.
+ * The table-type of the @asce identifies the portion of the @vaddr
+ * that is used as the invalidation index.
+ */
+static inline void gmap_idte_one(unsigned long asce, unsigned long vaddr)
+{
+	asm volatile(
+		"	.insn	rrf,0xb98e0000,%0,%1,0,0"
+		: : "a" (asce), "a" (vaddr) : "cc", "memory");
+}
+
+/**
+ * gmap_unshadow_page - remove a page from a shadow page table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void gmap_unshadow_page(struct gmap *sg, unsigned long raddr)
+{
+	unsigned long *table;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	table = gmap_table_walk(sg, raddr, 0); /* get page table pointer */
+	if (!table || *table & _PAGE_INVALID)
+		return;
+	gmap_call_notifier(sg, raddr, raddr + (1UL << 12) - 1);
+	ptep_unshadow_pte(sg->mm, raddr, (pte_t *) table);
+}
+
+/**
+ * __gmap_unshadow_pgt - remove all entries from a shadow page table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ * @pgt: pointer to the start of a shadow page table
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void __gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr,
+				unsigned long *pgt)
+{
+	int i;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	for (i = 0; i < 256; i++, raddr += 1UL << 12)
+		pgt[i] = _PAGE_INVALID;
+}
+
+/**
+ * gmap_unshadow_pgt - remove a shadow page table from a segment entry
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: address in the shadow guest address space
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr)
+{
+	unsigned long sto, *ste, *pgt;
+	struct page *page;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	ste = gmap_table_walk(sg, raddr, 1); /* get segment pointer */
+	if (!ste || !(*ste & _SEGMENT_ENTRY_ORIGIN))
+		return;
+	gmap_call_notifier(sg, raddr, raddr + (1UL << 20) - 1);
+	sto = (unsigned long) (ste - ((raddr >> 20) & 0x7ff));
+	gmap_idte_one(sto | _ASCE_TYPE_SEGMENT, raddr);
+	pgt = (unsigned long *)(*ste & _SEGMENT_ENTRY_ORIGIN);
+	*ste = _SEGMENT_ENTRY_EMPTY;
+	__gmap_unshadow_pgt(sg, raddr, pgt);
+	/* Free page table */
+	page = pfn_to_page(__pa(pgt) >> PAGE_SHIFT);
+	list_del(&page->lru);
+	page_table_free_pgste(page);
+}
+
+/**
+ * __gmap_unshadow_sgt - remove all entries from a shadow segment table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ * @sgt: pointer to the start of a shadow segment table
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void __gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr,
+				unsigned long *sgt)
+{
+	unsigned long asce, *pgt;
+	struct page *page;
+	int i;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	asce = (unsigned long) sgt | _ASCE_TYPE_SEGMENT;
+	for (i = 0; i < 2048; i++, raddr += 1UL << 20) {
+		if (!(sgt[i] & _SEGMENT_ENTRY_ORIGIN))
+			continue;
+		pgt = (unsigned long *)(sgt[i] & _REGION_ENTRY_ORIGIN);
+		sgt[i] = _SEGMENT_ENTRY_EMPTY;
+		__gmap_unshadow_pgt(sg, raddr, pgt);
+		/* Free page table */
+		page = pfn_to_page(__pa(pgt) >> PAGE_SHIFT);
+		list_del(&page->lru);
+		page_table_free_pgste(page);
+	}
+}
+
+/**
+ * gmap_unshadow_sgt - remove a shadow segment table from a region-3 entry
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ *
+ * Called with the shadow->guest_table_lock
+ */
+static void gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr)
+{
+	unsigned long r3o, *r3e, *sgt;
+	struct page *page;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	r3e = gmap_table_walk(sg, raddr, 2); /* get region-3 pointer */
+	if (!r3e || !(*r3e & _REGION_ENTRY_ORIGIN))
+		return;
+	gmap_call_notifier(sg, raddr, raddr + (1UL << 31) - 1);
+	r3o = (unsigned long) (r3e - ((raddr >> 31) & 0x7ff));
+	gmap_idte_one(r3o | _ASCE_TYPE_REGION3, raddr);
+	sgt = (unsigned long *)(*r3e & _REGION_ENTRY_ORIGIN);
+	*r3e = _REGION3_ENTRY_EMPTY;
+	__gmap_unshadow_sgt(sg, raddr, sgt);
+	/* Free segment table */
+	page = pfn_to_page(__pa(sgt) >> PAGE_SHIFT);
+	list_del(&page->lru);
+	__free_pages(page, 2);
+}
+
+/**
+ * __gmap_unshadow_r3t - remove all entries from a shadow region-3 table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: address in the shadow guest address space
+ * @r3t: pointer to the start of a shadow region-3 table
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void __gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr,
+				unsigned long *r3t)
+{
+	unsigned long asce, *sgt;
+	struct page *page;
+	int i;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	asce = (unsigned long) r3t | _ASCE_TYPE_REGION3;
+	for (i = 0; i < 2048; i++, raddr += 1UL << 31) {
+		if (!(r3t[i] & _REGION_ENTRY_ORIGIN))
+			continue;
+		sgt = (unsigned long *)(r3t[i] & _REGION_ENTRY_ORIGIN);
+		r3t[i] = _REGION3_ENTRY_EMPTY;
+		__gmap_unshadow_sgt(sg, raddr, sgt);
+		/* Free segment table */
+		page = pfn_to_page(__pa(sgt) >> PAGE_SHIFT);
+		list_del(&page->lru);
+		__free_pages(page, 2);
+	}
+}
+
+/**
+ * gmap_unshadow_r3t - remove a shadow region-3 table from a region-2 entry
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr)
+{
+	unsigned long r2o, *r2e, *r3t;
+	struct page *page;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	r2e = gmap_table_walk(sg, raddr, 3); /* get region-2 pointer */
+	if (!r2e || !(*r2e & _REGION_ENTRY_ORIGIN))
+		return;
+	gmap_call_notifier(sg, raddr, raddr + (1UL << 42) - 1);
+	r2o = (unsigned long) (r2e - ((raddr >> 42) & 0x7ff));
+	gmap_idte_one(r2o | _ASCE_TYPE_REGION2, raddr);
+	r3t = (unsigned long *)(*r2e & _REGION_ENTRY_ORIGIN);
+	*r2e = _REGION2_ENTRY_EMPTY;
+	__gmap_unshadow_r3t(sg, raddr, r3t);
+	/* Free region 3 table */
+	page = pfn_to_page(__pa(r3t) >> PAGE_SHIFT);
+	list_del(&page->lru);
+	__free_pages(page, 2);
+}
+
+/**
+ * __gmap_unshadow_r2t - remove all entries from a shadow region-2 table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ * @r2t: pointer to the start of a shadow region-2 table
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void __gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr,
+				unsigned long *r2t)
+{
+	unsigned long asce, *r3t;
+	struct page *page;
+	int i;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	asce = (unsigned long) r2t | _ASCE_TYPE_REGION2;
+	for (i = 0; i < 2048; i++, raddr += 1UL << 42) {
+		if (!(r2t[i] & _REGION_ENTRY_ORIGIN))
 			continue;
-		rc = __gmap_link(gmap, gaddr, addr);
+		r3t = (unsigned long *)(r2t[i] & _REGION_ENTRY_ORIGIN);
+		r2t[i] = _REGION2_ENTRY_EMPTY;
+		__gmap_unshadow_r3t(sg, raddr, r3t);
+		/* Free region 3 table */
+		page = pfn_to_page(__pa(r3t) >> PAGE_SHIFT);
+		list_del(&page->lru);
+		__free_pages(page, 2);
+	}
+}
+
+/**
+ * gmap_unshadow_r2t - remove a shadow region-2 table from a region-1 entry
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr)
+{
+	unsigned long r1o, *r1e, *r2t;
+	struct page *page;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	r1e = gmap_table_walk(sg, raddr, 4); /* get region-1 pointer */
+	if (!r1e || !(*r1e & _REGION_ENTRY_ORIGIN))
+		return;
+	gmap_call_notifier(sg, raddr, raddr + (1UL << 53) - 1);
+	r1o = (unsigned long) (r1e - ((raddr >> 53) & 0x7ff));
+	gmap_idte_one(r1o | _ASCE_TYPE_REGION1, raddr);
+	r2t = (unsigned long *)(*r1e & _REGION_ENTRY_ORIGIN);
+	*r1e = _REGION1_ENTRY_EMPTY;
+	__gmap_unshadow_r2t(sg, raddr, r2t);
+	/* Free region 2 table */
+	page = pfn_to_page(__pa(r2t) >> PAGE_SHIFT);
+	list_del(&page->lru);
+	__free_pages(page, 2);
+}
+
+/**
+ * __gmap_unshadow_r1t - remove all entries from a shadow region-1 table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ * @r1t: pointer to the start of a shadow region-1 table
+ *
+ * Called with the shadow->guest_table_lock
+ */
+static void __gmap_unshadow_r1t(struct gmap *sg, unsigned long raddr,
+				unsigned long *r1t)
+{
+	unsigned long asce, *r2t;
+	struct page *page;
+	int i;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	asce = (unsigned long) r1t | _ASCE_TYPE_REGION1;
+	for (i = 0; i < 2048; i++, raddr += 1UL << 53) {
+		if (!(r1t[i] & _REGION_ENTRY_ORIGIN))
+			continue;
+		r2t = (unsigned long *)(r1t[i] & _REGION_ENTRY_ORIGIN);
+		__gmap_unshadow_r2t(sg, raddr, r2t);
+		/* Clear entry and flush translation r1t -> r2t */
+		gmap_idte_one(asce, raddr);
+		r1t[i] = _REGION1_ENTRY_EMPTY;
+		/* Free region 2 table */
+		page = pfn_to_page(__pa(r2t) >> PAGE_SHIFT);
+		list_del(&page->lru);
+		__free_pages(page, 2);
+	}
+}
+
+/**
+ * gmap_unshadow - remove a shadow page table completely
+ * @sg: pointer to the shadow guest address space structure
+ *
+ * Called with sg->guest_table_lock
+ */
+static void gmap_unshadow(struct gmap *sg)
+{
+	unsigned long *table;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	if (sg->removed)
+		return;
+	sg->removed = 1;
+	gmap_call_notifier(sg, 0, -1UL);
+	gmap_flush_tlb(sg);
+	table = (unsigned long *)(sg->asce & _ASCE_ORIGIN);
+	switch (sg->asce & _ASCE_TYPE_MASK) {
+	case _ASCE_TYPE_REGION1:
+		__gmap_unshadow_r1t(sg, 0, table);
+		break;
+	case _ASCE_TYPE_REGION2:
+		__gmap_unshadow_r2t(sg, 0, table);
+		break;
+	case _ASCE_TYPE_REGION3:
+		__gmap_unshadow_r3t(sg, 0, table);
+		break;
+	case _ASCE_TYPE_SEGMENT:
+		__gmap_unshadow_sgt(sg, 0, table);
+		break;
+	}
+}
+
+/**
+ * gmap_find_shadow - find a specific asce in the list of shadow tables
+ * @parent: pointer to the parent gmap
+ * @asce: ASCE for which the shadow table is created
+ * @edat_level: edat level to be used for the shadow translation
+ *
+ * Returns the pointer to a gmap if a shadow table with the given asce is
+ * already available, ERR_PTR(-EAGAIN) if another one is just being created,
+ * otherwise NULL
+ */
+static struct gmap *gmap_find_shadow(struct gmap *parent, unsigned long asce,
+				     int edat_level)
+{
+	struct gmap *sg;
+
+	list_for_each_entry(sg, &parent->children, list) {
+		if (sg->orig_asce != asce || sg->edat_level != edat_level ||
+		    sg->removed)
+			continue;
+		if (!sg->initialized)
+			return ERR_PTR(-EAGAIN);
+		atomic_inc(&sg->ref_count);
+		return sg;
+	}
+	return NULL;
+}
+
+/**
+ * gmap_shadow_valid - check if a shadow guest address space matches the
+ *                     given properties and is still valid
+ * @sg: pointer to the shadow guest address space structure
+ * @asce: ASCE for which the shadow table is requested
+ * @edat_level: edat level to be used for the shadow translation
+ *
+ * Returns 1 if the gmap shadow is still valid and matches the given
+ * properties, the caller can continue using it. Returns 0 otherwise, the
+ * caller has to request a new shadow gmap in this case.
+ *
+ */
+int gmap_shadow_valid(struct gmap *sg, unsigned long asce, int edat_level)
+{
+	if (sg->removed)
+		return 0;
+	return sg->orig_asce == asce && sg->edat_level == edat_level;
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_valid);
+
+/**
+ * gmap_shadow - create/find a shadow guest address space
+ * @parent: pointer to the parent gmap
+ * @asce: ASCE for which the shadow table is created
+ * @edat_level: edat level to be used for the shadow translation
+ *
+ * The pages of the top level page table referred by the asce parameter
+ * will be set to read-only and marked in the PGSTEs of the kvm process.
+ * The shadow table will be removed automatically on any change to the
+ * PTE mapping for the source table.
+ *
+ * Returns a guest address space structure, ERR_PTR(-ENOMEM) if out of memory,
+ * ERR_PTR(-EAGAIN) if the caller has to retry and ERR_PTR(-EFAULT) if the
+ * parent gmap table could not be protected.
+ */
+struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce,
+			 int edat_level)
+{
+	struct gmap *sg, *new;
+	unsigned long limit;
+	int rc;
+
+	BUG_ON(gmap_is_shadow(parent));
+	spin_lock(&parent->shadow_lock);
+	sg = gmap_find_shadow(parent, asce, edat_level);
+	spin_unlock(&parent->shadow_lock);
+	if (sg)
+		return sg;
+	/* Create a new shadow gmap */
+	limit = -1UL >> (33 - (((asce & _ASCE_TYPE_MASK) >> 2) * 11));
+	if (asce & _ASCE_REAL_SPACE)
+		limit = -1UL;
+	new = gmap_alloc(limit);
+	if (!new)
+		return ERR_PTR(-ENOMEM);
+	new->mm = parent->mm;
+	new->parent = gmap_get(parent);
+	new->orig_asce = asce;
+	new->edat_level = edat_level;
+	new->initialized = false;
+	spin_lock(&parent->shadow_lock);
+	/* Recheck if another CPU created the same shadow */
+	sg = gmap_find_shadow(parent, asce, edat_level);
+	if (sg) {
+		spin_unlock(&parent->shadow_lock);
+		gmap_free(new);
+		return sg;
+	}
+	if (asce & _ASCE_REAL_SPACE) {
+		/* only allow one real-space gmap shadow */
+		list_for_each_entry(sg, &parent->children, list) {
+			if (sg->orig_asce & _ASCE_REAL_SPACE) {
+				spin_lock(&sg->guest_table_lock);
+				gmap_unshadow(sg);
+				spin_unlock(&sg->guest_table_lock);
+				list_del(&sg->list);
+				gmap_put(sg);
+				break;
+			}
+		}
+	}
+	atomic_set(&new->ref_count, 2);
+	list_add(&new->list, &parent->children);
+	if (asce & _ASCE_REAL_SPACE) {
+		/* nothing to protect, return right away */
+		new->initialized = true;
+		spin_unlock(&parent->shadow_lock);
+		return new;
+	}
+	spin_unlock(&parent->shadow_lock);
+	/* protect after insertion, so it will get properly invalidated */
+	down_read(&parent->mm->mmap_sem);
+	rc = gmap_protect_range(parent, asce & _ASCE_ORIGIN,
+				((asce & _ASCE_TABLE_LENGTH) + 1) * 4096,
+				PROT_READ, PGSTE_VSIE_BIT);
+	up_read(&parent->mm->mmap_sem);
+	spin_lock(&parent->shadow_lock);
+	new->initialized = true;
+	if (rc) {
+		list_del(&new->list);
+		gmap_free(new);
+		new = ERR_PTR(rc);
+	}
+	spin_unlock(&parent->shadow_lock);
+	return new;
+}
+EXPORT_SYMBOL_GPL(gmap_shadow);
+
+/**
+ * gmap_shadow_r2t - create an empty shadow region 2 table
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @r2t: parent gmap address of the region 2 table to get shadowed
+ * @fake: r2t references contiguous guest memory block, not a r2t
+ *
+ * The r2t parameter specifies the address of the source table. The
+ * four pages of the source table are made read-only in the parent gmap
+ * address space. A write to the source table area @r2t will automatically
+ * remove the shadow r2 table and all of its decendents.
+ *
+ * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
+ * shadow table structure is incomplete, -ENOMEM if out of memory and
+ * -EFAULT if an address in the parent gmap could not be resolved.
+ *
+ * Called with sg->mm->mmap_sem in read.
+ */
+int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t,
+		    int fake)
+{
+	unsigned long raddr, origin, offset, len;
+	unsigned long *s_r2t, *table;
+	struct page *page;
+	int rc;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	/* Allocate a shadow region second table */
+	page = alloc_pages(GFP_KERNEL, 2);
+	if (!page)
+		return -ENOMEM;
+	page->index = r2t & _REGION_ENTRY_ORIGIN;
+	if (fake)
+		page->index |= GMAP_SHADOW_FAKE_TABLE;
+	s_r2t = (unsigned long *) page_to_phys(page);
+	/* Install shadow region second table */
+	spin_lock(&sg->guest_table_lock);
+	table = gmap_table_walk(sg, saddr, 4); /* get region-1 pointer */
+	if (!table) {
+		rc = -EAGAIN;		/* Race with unshadow */
+		goto out_free;
+	}
+	if (!(*table & _REGION_ENTRY_INVALID)) {
+		rc = 0;			/* Already established */
+		goto out_free;
+	} else if (*table & _REGION_ENTRY_ORIGIN) {
+		rc = -EAGAIN;		/* Race with shadow */
+		goto out_free;
+	}
+	crst_table_init(s_r2t, _REGION2_ENTRY_EMPTY);
+	/* mark as invalid as long as the parent table is not protected */
+	*table = (unsigned long) s_r2t | _REGION_ENTRY_LENGTH |
+		 _REGION_ENTRY_TYPE_R1 | _REGION_ENTRY_INVALID;
+	if (sg->edat_level >= 1)
+		*table |= (r2t & _REGION_ENTRY_PROTECT);
+	list_add(&page->lru, &sg->crst_list);
+	if (fake) {
+		/* nothing to protect for fake tables */
+		*table &= ~_REGION_ENTRY_INVALID;
+		spin_unlock(&sg->guest_table_lock);
+		return 0;
+	}
+	spin_unlock(&sg->guest_table_lock);
+	/* Make r2t read-only in parent gmap page table */
+	raddr = (saddr & 0xffe0000000000000UL) | _SHADOW_RMAP_REGION1;
+	origin = r2t & _REGION_ENTRY_ORIGIN;
+	offset = ((r2t & _REGION_ENTRY_OFFSET) >> 6) * 4096;
+	len = ((r2t & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset;
+	rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
+	spin_lock(&sg->guest_table_lock);
+	if (!rc) {
+		table = gmap_table_walk(sg, saddr, 4);
+		if (!table || (*table & _REGION_ENTRY_ORIGIN) !=
+			      (unsigned long) s_r2t)
+			rc = -EAGAIN;		/* Race with unshadow */
+		else
+			*table &= ~_REGION_ENTRY_INVALID;
+	} else {
+		gmap_unshadow_r2t(sg, raddr);
+	}
+	spin_unlock(&sg->guest_table_lock);
+	return rc;
+out_free:
+	spin_unlock(&sg->guest_table_lock);
+	__free_pages(page, 2);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_r2t);
+
+/**
+ * gmap_shadow_r3t - create a shadow region 3 table
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @r3t: parent gmap address of the region 3 table to get shadowed
+ * @fake: r3t references contiguous guest memory block, not a r3t
+ *
+ * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
+ * shadow table structure is incomplete, -ENOMEM if out of memory and
+ * -EFAULT if an address in the parent gmap could not be resolved.
+ *
+ * Called with sg->mm->mmap_sem in read.
+ */
+int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t,
+		    int fake)
+{
+	unsigned long raddr, origin, offset, len;
+	unsigned long *s_r3t, *table;
+	struct page *page;
+	int rc;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	/* Allocate a shadow region second table */
+	page = alloc_pages(GFP_KERNEL, 2);
+	if (!page)
+		return -ENOMEM;
+	page->index = r3t & _REGION_ENTRY_ORIGIN;
+	if (fake)
+		page->index |= GMAP_SHADOW_FAKE_TABLE;
+	s_r3t = (unsigned long *) page_to_phys(page);
+	/* Install shadow region second table */
+	spin_lock(&sg->guest_table_lock);
+	table = gmap_table_walk(sg, saddr, 3); /* get region-2 pointer */
+	if (!table) {
+		rc = -EAGAIN;		/* Race with unshadow */
+		goto out_free;
+	}
+	if (!(*table & _REGION_ENTRY_INVALID)) {
+		rc = 0;			/* Already established */
+		goto out_free;
+	} else if (*table & _REGION_ENTRY_ORIGIN) {
+		rc = -EAGAIN;		/* Race with shadow */
+	}
+	crst_table_init(s_r3t, _REGION3_ENTRY_EMPTY);
+	/* mark as invalid as long as the parent table is not protected */
+	*table = (unsigned long) s_r3t | _REGION_ENTRY_LENGTH |
+		 _REGION_ENTRY_TYPE_R2 | _REGION_ENTRY_INVALID;
+	if (sg->edat_level >= 1)
+		*table |= (r3t & _REGION_ENTRY_PROTECT);
+	list_add(&page->lru, &sg->crst_list);
+	if (fake) {
+		/* nothing to protect for fake tables */
+		*table &= ~_REGION_ENTRY_INVALID;
+		spin_unlock(&sg->guest_table_lock);
+		return 0;
+	}
+	spin_unlock(&sg->guest_table_lock);
+	/* Make r3t read-only in parent gmap page table */
+	raddr = (saddr & 0xfffffc0000000000UL) | _SHADOW_RMAP_REGION2;
+	origin = r3t & _REGION_ENTRY_ORIGIN;
+	offset = ((r3t & _REGION_ENTRY_OFFSET) >> 6) * 4096;
+	len = ((r3t & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset;
+	rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
+	spin_lock(&sg->guest_table_lock);
+	if (!rc) {
+		table = gmap_table_walk(sg, saddr, 3);
+		if (!table || (*table & _REGION_ENTRY_ORIGIN) !=
+			      (unsigned long) s_r3t)
+			rc = -EAGAIN;		/* Race with unshadow */
+		else
+			*table &= ~_REGION_ENTRY_INVALID;
+	} else {
+		gmap_unshadow_r3t(sg, raddr);
+	}
+	spin_unlock(&sg->guest_table_lock);
+	return rc;
+out_free:
+	spin_unlock(&sg->guest_table_lock);
+	__free_pages(page, 2);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_r3t);
+
+/**
+ * gmap_shadow_sgt - create a shadow segment table
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @sgt: parent gmap address of the segment table to get shadowed
+ * @fake: sgt references contiguous guest memory block, not a sgt
+ *
+ * Returns: 0 if successfully shadowed or already shadowed, -EAGAIN if the
+ * shadow table structure is incomplete, -ENOMEM if out of memory and
+ * -EFAULT if an address in the parent gmap could not be resolved.
+ *
+ * Called with sg->mm->mmap_sem in read.
+ */
+int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt,
+		    int fake)
+{
+	unsigned long raddr, origin, offset, len;
+	unsigned long *s_sgt, *table;
+	struct page *page;
+	int rc;
+
+	BUG_ON(!gmap_is_shadow(sg) || (sgt & _REGION3_ENTRY_LARGE));
+	/* Allocate a shadow segment table */
+	page = alloc_pages(GFP_KERNEL, 2);
+	if (!page)
+		return -ENOMEM;
+	page->index = sgt & _REGION_ENTRY_ORIGIN;
+	if (fake)
+		page->index |= GMAP_SHADOW_FAKE_TABLE;
+	s_sgt = (unsigned long *) page_to_phys(page);
+	/* Install shadow region second table */
+	spin_lock(&sg->guest_table_lock);
+	table = gmap_table_walk(sg, saddr, 2); /* get region-3 pointer */
+	if (!table) {
+		rc = -EAGAIN;		/* Race with unshadow */
+		goto out_free;
+	}
+	if (!(*table & _REGION_ENTRY_INVALID)) {
+		rc = 0;			/* Already established */
+		goto out_free;
+	} else if (*table & _REGION_ENTRY_ORIGIN) {
+		rc = -EAGAIN;		/* Race with shadow */
+		goto out_free;
+	}
+	crst_table_init(s_sgt, _SEGMENT_ENTRY_EMPTY);
+	/* mark as invalid as long as the parent table is not protected */
+	*table = (unsigned long) s_sgt | _REGION_ENTRY_LENGTH |
+		 _REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_INVALID;
+	if (sg->edat_level >= 1)
+		*table |= sgt & _REGION_ENTRY_PROTECT;
+	list_add(&page->lru, &sg->crst_list);
+	if (fake) {
+		/* nothing to protect for fake tables */
+		*table &= ~_REGION_ENTRY_INVALID;
+		spin_unlock(&sg->guest_table_lock);
+		return 0;
+	}
+	spin_unlock(&sg->guest_table_lock);
+	/* Make sgt read-only in parent gmap page table */
+	raddr = (saddr & 0xffffffff80000000UL) | _SHADOW_RMAP_REGION3;
+	origin = sgt & _REGION_ENTRY_ORIGIN;
+	offset = ((sgt & _REGION_ENTRY_OFFSET) >> 6) * 4096;
+	len = ((sgt & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset;
+	rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
+	spin_lock(&sg->guest_table_lock);
+	if (!rc) {
+		table = gmap_table_walk(sg, saddr, 2);
+		if (!table || (*table & _REGION_ENTRY_ORIGIN) !=
+			      (unsigned long) s_sgt)
+			rc = -EAGAIN;		/* Race with unshadow */
+		else
+			*table &= ~_REGION_ENTRY_INVALID;
+	} else {
+		gmap_unshadow_sgt(sg, raddr);
+	}
+	spin_unlock(&sg->guest_table_lock);
+	return rc;
+out_free:
+	spin_unlock(&sg->guest_table_lock);
+	__free_pages(page, 2);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_sgt);
+
+/**
+ * gmap_shadow_lookup_pgtable - find a shadow page table
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: the address in the shadow aguest address space
+ * @pgt: parent gmap address of the page table to get shadowed
+ * @dat_protection: if the pgtable is marked as protected by dat
+ * @fake: pgt references contiguous guest memory block, not a pgtable
+ *
+ * Returns 0 if the shadow page table was found and -EAGAIN if the page
+ * table was not found.
+ *
+ * Called with sg->mm->mmap_sem in read.
+ */
+int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,
+			   unsigned long *pgt, int *dat_protection,
+			   int *fake)
+{
+	unsigned long *table;
+	struct page *page;
+	int rc;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	spin_lock(&sg->guest_table_lock);
+	table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */
+	if (table && !(*table & _SEGMENT_ENTRY_INVALID)) {
+		/* Shadow page tables are full pages (pte+pgste) */
+		page = pfn_to_page(*table >> PAGE_SHIFT);
+		*pgt = page->index & ~GMAP_SHADOW_FAKE_TABLE;
+		*dat_protection = !!(*table & _SEGMENT_ENTRY_PROTECT);
+		*fake = !!(page->index & GMAP_SHADOW_FAKE_TABLE);
+		rc = 0;
+	} else  {
+		rc = -EAGAIN;
+	}
+	spin_unlock(&sg->guest_table_lock);
+	return rc;
+
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_pgt_lookup);
+
+/**
+ * gmap_shadow_pgt - instantiate a shadow page table
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @pgt: parent gmap address of the page table to get shadowed
+ * @fake: pgt references contiguous guest memory block, not a pgtable
+ *
+ * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
+ * shadow table structure is incomplete, -ENOMEM if out of memory,
+ * -EFAULT if an address in the parent gmap could not be resolved and
+ *
+ * Called with gmap->mm->mmap_sem in read
+ */
+int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt,
+		    int fake)
+{
+	unsigned long raddr, origin;
+	unsigned long *s_pgt, *table;
+	struct page *page;
+	int rc;
+
+	BUG_ON(!gmap_is_shadow(sg) || (pgt & _SEGMENT_ENTRY_LARGE));
+	/* Allocate a shadow page table */
+	page = page_table_alloc_pgste(sg->mm);
+	if (!page)
+		return -ENOMEM;
+	page->index = pgt & _SEGMENT_ENTRY_ORIGIN;
+	if (fake)
+		page->index |= GMAP_SHADOW_FAKE_TABLE;
+	s_pgt = (unsigned long *) page_to_phys(page);
+	/* Install shadow page table */
+	spin_lock(&sg->guest_table_lock);
+	table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */
+	if (!table) {
+		rc = -EAGAIN;		/* Race with unshadow */
+		goto out_free;
+	}
+	if (!(*table & _SEGMENT_ENTRY_INVALID)) {
+		rc = 0;			/* Already established */
+		goto out_free;
+	} else if (*table & _SEGMENT_ENTRY_ORIGIN) {
+		rc = -EAGAIN;		/* Race with shadow */
+		goto out_free;
+	}
+	/* mark as invalid as long as the parent table is not protected */
+	*table = (unsigned long) s_pgt | _SEGMENT_ENTRY |
+		 (pgt & _SEGMENT_ENTRY_PROTECT) | _SEGMENT_ENTRY_INVALID;
+	list_add(&page->lru, &sg->pt_list);
+	if (fake) {
+		/* nothing to protect for fake tables */
+		*table &= ~_SEGMENT_ENTRY_INVALID;
+		spin_unlock(&sg->guest_table_lock);
+		return 0;
+	}
+	spin_unlock(&sg->guest_table_lock);
+	/* Make pgt read-only in parent gmap page table (not the pgste) */
+	raddr = (saddr & 0xfffffffffff00000UL) | _SHADOW_RMAP_SEGMENT;
+	origin = pgt & _SEGMENT_ENTRY_ORIGIN & PAGE_MASK;
+	rc = gmap_protect_rmap(sg, raddr, origin, PAGE_SIZE, PROT_READ);
+	spin_lock(&sg->guest_table_lock);
+	if (!rc) {
+		table = gmap_table_walk(sg, saddr, 1);
+		if (!table || (*table & _SEGMENT_ENTRY_ORIGIN) !=
+			      (unsigned long) s_pgt)
+			rc = -EAGAIN;		/* Race with unshadow */
+		else
+			*table &= ~_SEGMENT_ENTRY_INVALID;
+	} else {
+		gmap_unshadow_pgt(sg, raddr);
+	}
+	spin_unlock(&sg->guest_table_lock);
+	return rc;
+out_free:
+	spin_unlock(&sg->guest_table_lock);
+	page_table_free_pgste(page);
+	return rc;
+
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_pgt);
+
+/**
+ * gmap_shadow_page - create a shadow page mapping
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @pte: pte in parent gmap address space to get shadowed
+ *
+ * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
+ * shadow table structure is incomplete, -ENOMEM if out of memory and
+ * -EFAULT if an address in the parent gmap could not be resolved.
+ *
+ * Called with sg->mm->mmap_sem in read.
+ */
+int gmap_shadow_page(struct gmap *sg, unsigned long saddr, pte_t pte)
+{
+	struct gmap *parent;
+	struct gmap_rmap *rmap;
+	unsigned long vmaddr, paddr;
+	spinlock_t *ptl;
+	pte_t *sptep, *tptep;
+	int prot;
+	int rc;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	parent = sg->parent;
+	prot = (pte_val(pte) & _PAGE_PROTECT) ? PROT_READ : PROT_WRITE;
+
+	rmap = kzalloc(sizeof(*rmap), GFP_KERNEL);
+	if (!rmap)
+		return -ENOMEM;
+	rmap->raddr = (saddr & PAGE_MASK) | _SHADOW_RMAP_PGTABLE;
+
+	while (1) {
+		paddr = pte_val(pte) & PAGE_MASK;
+		vmaddr = __gmap_translate(parent, paddr);
+		if (IS_ERR_VALUE(vmaddr)) {
+			rc = vmaddr;
+			break;
+		}
+		rc = radix_tree_preload(GFP_KERNEL);
 		if (rc)
 			break;
-		/* Walk the process page table, lock and get pte pointer */
-		ptep = get_locked_pte(gmap->mm, addr, &ptl);
-		VM_BUG_ON(!ptep);
-		/* Set notification bit in the pgste of the pte */
-		if ((pte_val(*ptep) & (_PAGE_INVALID | _PAGE_PROTECT)) == 0) {
-			ptep_set_notify(gmap->mm, addr, ptep);
-			gaddr += PAGE_SIZE;
-			len -= PAGE_SIZE;
+		rc = -EAGAIN;
+		sptep = gmap_pte_op_walk(parent, paddr, &ptl);
+		if (sptep) {
+			spin_lock(&sg->guest_table_lock);
+			/* Get page table pointer */
+			tptep = (pte_t *) gmap_table_walk(sg, saddr, 0);
+			if (!tptep) {
+				spin_unlock(&sg->guest_table_lock);
+				gmap_pte_op_end(ptl);
+				radix_tree_preload_end();
+				break;
+			}
+			rc = ptep_shadow_pte(sg->mm, saddr, sptep, tptep, pte);
+			if (rc > 0) {
+				/* Success and a new mapping */
+				gmap_insert_rmap(sg, vmaddr, rmap);
+				rmap = NULL;
+				rc = 0;
+			}
+			gmap_pte_op_end(ptl);
+			spin_unlock(&sg->guest_table_lock);
 		}
-		pte_unmap_unlock(ptep, ptl);
+		radix_tree_preload_end();
+		if (!rc)
+			break;
+		rc = gmap_pte_op_fixup(parent, paddr, vmaddr, prot);
+		if (rc)
+			break;
 	}
-	up_read(&gmap->mm->mmap_sem);
+	kfree(rmap);
 	return rc;
 }
-EXPORT_SYMBOL_GPL(gmap_ipte_notify);
+EXPORT_SYMBOL_GPL(gmap_shadow_page);
+
+/**
+ * gmap_shadow_notify - handle notifications for shadow gmap
+ *
+ * Called with sg->parent->shadow_lock.
+ */
+static void gmap_shadow_notify(struct gmap *sg, unsigned long vmaddr,
+			       unsigned long offset, pte_t *pte)
+{
+	struct gmap_rmap *rmap, *rnext, *head;
+	unsigned long gaddr, start, end, bits, raddr;
+	unsigned long *table;
+
+	BUG_ON(!gmap_is_shadow(sg));
+	spin_lock(&sg->parent->guest_table_lock);
+	table = radix_tree_lookup(&sg->parent->host_to_guest,
+				  vmaddr >> PMD_SHIFT);
+	gaddr = table ? __gmap_segment_gaddr(table) + offset : 0;
+	spin_unlock(&sg->parent->guest_table_lock);
+	if (!table)
+		return;
+
+	spin_lock(&sg->guest_table_lock);
+	if (sg->removed) {
+		spin_unlock(&sg->guest_table_lock);
+		return;
+	}
+	/* Check for top level table */
+	start = sg->orig_asce & _ASCE_ORIGIN;
+	end = start + ((sg->orig_asce & _ASCE_TABLE_LENGTH) + 1) * 4096;
+	if (!(sg->orig_asce & _ASCE_REAL_SPACE) && gaddr >= start &&
+	    gaddr < end) {
+		/* The complete shadow table has to go */
+		gmap_unshadow(sg);
+		spin_unlock(&sg->guest_table_lock);
+		list_del(&sg->list);
+		gmap_put(sg);
+		return;
+	}
+	/* Remove the page table tree from on specific entry */
+	head = radix_tree_delete(&sg->host_to_rmap, vmaddr >> 12);
+	gmap_for_each_rmap_safe(rmap, rnext, head) {
+		bits = rmap->raddr & _SHADOW_RMAP_MASK;
+		raddr = rmap->raddr ^ bits;
+		switch (bits) {
+		case _SHADOW_RMAP_REGION1:
+			gmap_unshadow_r2t(sg, raddr);
+			break;
+		case _SHADOW_RMAP_REGION2:
+			gmap_unshadow_r3t(sg, raddr);
+			break;
+		case _SHADOW_RMAP_REGION3:
+			gmap_unshadow_sgt(sg, raddr);
+			break;
+		case _SHADOW_RMAP_SEGMENT:
+			gmap_unshadow_pgt(sg, raddr);
+			break;
+		case _SHADOW_RMAP_PGTABLE:
+			gmap_unshadow_page(sg, raddr);
+			break;
+		}
+		kfree(rmap);
+	}
+	spin_unlock(&sg->guest_table_lock);
+}
 
 /**
  * ptep_notify - call all invalidation callbacks for a specific pte.
  * @mm: pointer to the process mm_struct
  * @addr: virtual address in the process address space
  * @pte: pointer to the page table entry
+ * @bits: bits from the pgste that caused the notify call
  *
  * This function is assumed to be called with the page table lock held
  * for the pte to notify.
  */
-void ptep_notify(struct mm_struct *mm, unsigned long vmaddr, pte_t *pte)
+void ptep_notify(struct mm_struct *mm, unsigned long vmaddr,
+		 pte_t *pte, unsigned long bits)
 {
 	unsigned long offset, gaddr;
 	unsigned long *table;
-	struct gmap_notifier *nb;
-	struct gmap *gmap;
+	struct gmap *gmap, *sg, *next;
 
 	offset = ((unsigned long) pte) & (255 * sizeof(pte_t));
 	offset = offset * (4096 / sizeof(pte_t));
-	spin_lock(&gmap_notifier_lock);
-	list_for_each_entry(gmap, &mm->context.gmap_list, list) {
+	rcu_read_lock();
+	list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) {
+		if (!list_empty(&gmap->children) && (bits & PGSTE_VSIE_BIT)) {
+			spin_lock(&gmap->shadow_lock);
+			list_for_each_entry_safe(sg, next,
+						 &gmap->children, list)
+				gmap_shadow_notify(sg, vmaddr, offset, pte);
+			spin_unlock(&gmap->shadow_lock);
+		}
+		if (!(bits & PGSTE_IN_BIT))
+			continue;
+		spin_lock(&gmap->guest_table_lock);
 		table = radix_tree_lookup(&gmap->host_to_guest,
 					  vmaddr >> PMD_SHIFT);
-		if (!table)
-			continue;
-		gaddr = __gmap_segment_gaddr(table) + offset;
-		list_for_each_entry(nb, &gmap_notifier_list, list)
-			nb->notifier_call(gmap, gaddr);
+		if (table)
+			gaddr = __gmap_segment_gaddr(table) + offset;
+		spin_unlock(&gmap->guest_table_lock);
+		if (table)
+			gmap_call_notifier(gmap, gaddr, gaddr + PAGE_SIZE - 1);
 	}
-	spin_unlock(&gmap_notifier_lock);
+	rcu_read_unlock();
 }
 EXPORT_SYMBOL_GPL(ptep_notify);
 
diff --git a/arch/s390/mm/gup.c b/arch/s390/mm/gup.c
index a8a6765f1..adb0c34bf 100644
--- a/arch/s390/mm/gup.c
+++ b/arch/s390/mm/gup.c
@@ -128,6 +128,44 @@ static inline int gup_pmd_range(pud_t *pudp, pud_t pud, unsigned long addr,
 	return 1;
 }
 
+static int gup_huge_pud(pud_t *pudp, pud_t pud, unsigned long addr,
+		unsigned long end, int write, struct page **pages, int *nr)
+{
+	struct page *head, *page;
+	unsigned long mask;
+	int refs;
+
+	mask = (write ? _REGION_ENTRY_PROTECT : 0) | _REGION_ENTRY_INVALID;
+	if ((pud_val(pud) & mask) != 0)
+		return 0;
+	VM_BUG_ON(!pfn_valid(pud_pfn(pud)));
+
+	refs = 0;
+	head = pud_page(pud);
+	page = head + ((addr & ~PUD_MASK) >> PAGE_SHIFT);
+	do {
+		VM_BUG_ON_PAGE(compound_head(page) != head, page);
+		pages[*nr] = page;
+		(*nr)++;
+		page++;
+		refs++;
+	} while (addr += PAGE_SIZE, addr != end);
+
+	if (!page_cache_add_speculative(head, refs)) {
+		*nr -= refs;
+		return 0;
+	}
+
+	if (unlikely(pud_val(pud) != pud_val(*pudp))) {
+		*nr -= refs;
+		while (refs--)
+			put_page(head);
+		return 0;
+	}
+
+	return 1;
+}
+
 static inline int gup_pud_range(pgd_t *pgdp, pgd_t pgd, unsigned long addr,
 		unsigned long end, int write, struct page **pages, int *nr)
 {
@@ -144,7 +182,12 @@ static inline int gup_pud_range(pgd_t *pgdp, pgd_t pgd, unsigned long addr,
 		next = pud_addr_end(addr, end);
 		if (pud_none(pud))
 			return 0;
-		if (!gup_pmd_range(pudp, pud, addr, next, write, pages, nr))
+		if (unlikely(pud_large(pud))) {
+			if (!gup_huge_pud(pudp, pud, addr, next, write, pages,
+					  nr))
+				return 0;
+		} else if (!gup_pmd_range(pudp, pud, addr, next, write, pages,
+					  nr))
 			return 0;
 	} while (pudp++, addr = next, addr != end);
 
diff --git a/arch/s390/mm/hugetlbpage.c b/arch/s390/mm/hugetlbpage.c
index 1b5e8983f..cd404aa39 100644
--- a/arch/s390/mm/hugetlbpage.c
+++ b/arch/s390/mm/hugetlbpage.c
@@ -1,19 +1,28 @@
 /*
  *  IBM System z Huge TLB Page Support for Kernel.
  *
- *    Copyright IBM Corp. 2007
+ *    Copyright IBM Corp. 2007,2016
  *    Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com>
  */
 
+#define KMSG_COMPONENT "hugetlb"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
 #include <linux/mm.h>
 #include <linux/hugetlb.h>
 
-static inline pmd_t __pte_to_pmd(pte_t pte)
+/*
+ * If the bit selected by single-bit bitmask "a" is set within "x", move
+ * it to the position indicated by single-bit bitmask "b".
+ */
+#define move_set_bit(x, a, b)	(((x) & (a)) >> ilog2(a) << ilog2(b))
+
+static inline unsigned long __pte_to_rste(pte_t pte)
 {
-	pmd_t pmd;
+	unsigned long rste;
 
 	/*
-	 * Convert encoding		  pte bits	   pmd bits
+	 * Convert encoding		  pte bits	pmd / pud bits
 	 *				lIR.uswrdy.p	dy..R...I...wr
 	 * empty			010.000000.0 -> 00..0...1...00
 	 * prot-none, clean, old	111.000000.1 -> 00..1...1...00
@@ -33,25 +42,40 @@ static inline pmd_t __pte_to_pmd(pte_t pte)
 	 *	    u unused, l large
 	 */
 	if (pte_present(pte)) {
-		pmd_val(pmd) = pte_val(pte) & PAGE_MASK;
-		pmd_val(pmd) |= (pte_val(pte) & _PAGE_READ) >> 4;
-		pmd_val(pmd) |= (pte_val(pte) & _PAGE_WRITE) >> 4;
-		pmd_val(pmd) |=	(pte_val(pte) & _PAGE_INVALID) >> 5;
-		pmd_val(pmd) |= (pte_val(pte) & _PAGE_PROTECT);
-		pmd_val(pmd) |= (pte_val(pte) & _PAGE_DIRTY) << 10;
-		pmd_val(pmd) |= (pte_val(pte) & _PAGE_YOUNG) << 10;
-		pmd_val(pmd) |= (pte_val(pte) & _PAGE_SOFT_DIRTY) << 13;
+		rste = pte_val(pte) & PAGE_MASK;
+		rste |= move_set_bit(pte_val(pte), _PAGE_READ,
+				     _SEGMENT_ENTRY_READ);
+		rste |= move_set_bit(pte_val(pte), _PAGE_WRITE,
+				     _SEGMENT_ENTRY_WRITE);
+		rste |= move_set_bit(pte_val(pte), _PAGE_INVALID,
+				     _SEGMENT_ENTRY_INVALID);
+		rste |= move_set_bit(pte_val(pte), _PAGE_PROTECT,
+				     _SEGMENT_ENTRY_PROTECT);
+		rste |= move_set_bit(pte_val(pte), _PAGE_DIRTY,
+				     _SEGMENT_ENTRY_DIRTY);
+		rste |= move_set_bit(pte_val(pte), _PAGE_YOUNG,
+				     _SEGMENT_ENTRY_YOUNG);
+#ifdef CONFIG_MEM_SOFT_DIRTY
+		rste |= move_set_bit(pte_val(pte), _PAGE_SOFT_DIRTY,
+				     _SEGMENT_ENTRY_SOFT_DIRTY);
+#endif
 	} else
-		pmd_val(pmd) = _SEGMENT_ENTRY_INVALID;
-	return pmd;
+		rste = _SEGMENT_ENTRY_INVALID;
+	return rste;
 }
 
-static inline pte_t __pmd_to_pte(pmd_t pmd)
+static inline pte_t __rste_to_pte(unsigned long rste)
 {
+	int present;
 	pte_t pte;
 
+	if ((rste & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
+		present = pud_present(__pud(rste));
+	else
+		present = pmd_present(__pmd(rste));
+
 	/*
-	 * Convert encoding		   pmd bits	    pte bits
+	 * Convert encoding		pmd / pud bits	    pte bits
 	 *				dy..R...I...wr	  lIR.uswrdy.p
 	 * empty			00..0...1...00 -> 010.000000.0
 	 * prot-none, clean, old	00..1...1...00 -> 111.000000.1
@@ -70,16 +94,25 @@ static inline pte_t __pmd_to_pte(pmd_t pmd)
 	 * SW-bits: p present, y young, d dirty, r read, w write, s special,
 	 *	    u unused, l large
 	 */
-	if (pmd_present(pmd)) {
-		pte_val(pte) = pmd_val(pmd) & _SEGMENT_ENTRY_ORIGIN_LARGE;
+	if (present) {
+		pte_val(pte) = rste & _SEGMENT_ENTRY_ORIGIN_LARGE;
 		pte_val(pte) |= _PAGE_LARGE | _PAGE_PRESENT;
-		pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_READ) << 4;
-		pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_WRITE) << 4;
-		pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_INVALID) << 5;
-		pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_PROTECT);
-		pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_DIRTY) >> 10;
-		pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_YOUNG) >> 10;
-		pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_SOFT_DIRTY) >> 13;
+		pte_val(pte) |= move_set_bit(rste, _SEGMENT_ENTRY_READ,
+					     _PAGE_READ);
+		pte_val(pte) |= move_set_bit(rste, _SEGMENT_ENTRY_WRITE,
+					     _PAGE_WRITE);
+		pte_val(pte) |= move_set_bit(rste, _SEGMENT_ENTRY_INVALID,
+					     _PAGE_INVALID);
+		pte_val(pte) |= move_set_bit(rste, _SEGMENT_ENTRY_PROTECT,
+					     _PAGE_PROTECT);
+		pte_val(pte) |= move_set_bit(rste, _SEGMENT_ENTRY_DIRTY,
+					     _PAGE_DIRTY);
+		pte_val(pte) |= move_set_bit(rste, _SEGMENT_ENTRY_YOUNG,
+					     _PAGE_YOUNG);
+#ifdef CONFIG_MEM_SOFT_DIRTY
+		pte_val(pte) |= move_set_bit(rste, _SEGMENT_ENTRY_SOFT_DIRTY,
+					     _PAGE_DIRTY);
+#endif
 	} else
 		pte_val(pte) = _PAGE_INVALID;
 	return pte;
@@ -88,27 +121,33 @@ static inline pte_t __pmd_to_pte(pmd_t pmd)
 void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
 		     pte_t *ptep, pte_t pte)
 {
-	pmd_t pmd = __pte_to_pmd(pte);
-
-	pmd_val(pmd) |= _SEGMENT_ENTRY_LARGE;
-	*(pmd_t *) ptep = pmd;
+	unsigned long rste = __pte_to_rste(pte);
+
+	/* Set correct table type for 2G hugepages */
+	if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
+		rste |= _REGION_ENTRY_TYPE_R3 | _REGION3_ENTRY_LARGE;
+	else
+		rste |= _SEGMENT_ENTRY_LARGE;
+	pte_val(*ptep) = rste;
 }
 
 pte_t huge_ptep_get(pte_t *ptep)
 {
-	pmd_t pmd = *(pmd_t *) ptep;
-
-	return __pmd_to_pte(pmd);
+	return __rste_to_pte(pte_val(*ptep));
 }
 
 pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
 			      unsigned long addr, pte_t *ptep)
 {
+	pte_t pte = huge_ptep_get(ptep);
 	pmd_t *pmdp = (pmd_t *) ptep;
-	pmd_t old;
+	pud_t *pudp = (pud_t *) ptep;
 
-	old = pmdp_xchg_direct(mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_EMPTY));
-	return __pmd_to_pte(old);
+	if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
+		pudp_xchg_direct(mm, addr, pudp, __pud(_REGION3_ENTRY_EMPTY));
+	else
+		pmdp_xchg_direct(mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_EMPTY));
+	return pte;
 }
 
 pte_t *huge_pte_alloc(struct mm_struct *mm,
@@ -120,8 +159,12 @@ pte_t *huge_pte_alloc(struct mm_struct *mm,
 
 	pgdp = pgd_offset(mm, addr);
 	pudp = pud_alloc(mm, pgdp, addr);
-	if (pudp)
-		pmdp = pmd_alloc(mm, pudp, addr);
+	if (pudp) {
+		if (sz == PUD_SIZE)
+			return (pte_t *) pudp;
+		else if (sz == PMD_SIZE)
+			pmdp = pmd_alloc(mm, pudp, addr);
+	}
 	return (pte_t *) pmdp;
 }
 
@@ -134,8 +177,11 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
 	pgdp = pgd_offset(mm, addr);
 	if (pgd_present(*pgdp)) {
 		pudp = pud_offset(pgdp, addr);
-		if (pud_present(*pudp))
+		if (pud_present(*pudp)) {
+			if (pud_large(*pudp))
+				return (pte_t *) pudp;
 			pmdp = pmd_offset(pudp, addr);
+		}
 	}
 	return (pte_t *) pmdp;
 }
@@ -147,5 +193,34 @@ int pmd_huge(pmd_t pmd)
 
 int pud_huge(pud_t pud)
 {
-	return 0;
+	return pud_large(pud);
+}
+
+struct page *
+follow_huge_pud(struct mm_struct *mm, unsigned long address,
+		pud_t *pud, int flags)
+{
+	if (flags & FOLL_GET)
+		return NULL;
+
+	return pud_page(*pud) + ((address & ~PUD_MASK) >> PAGE_SHIFT);
+}
+
+static __init int setup_hugepagesz(char *opt)
+{
+	unsigned long size;
+	char *string = opt;
+
+	size = memparse(opt, &opt);
+	if (MACHINE_HAS_EDAT1 && size == PMD_SIZE) {
+		hugetlb_add_hstate(PMD_SHIFT - PAGE_SHIFT);
+	} else if (MACHINE_HAS_EDAT2 && size == PUD_SIZE) {
+		hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT);
+	} else {
+		pr_err("hugepagesz= specifies an unsupported page size %s\n",
+			string);
+		return 0;
+	}
+	return 1;
 }
+__setup("hugepagesz=", setup_hugepagesz);
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index 2489b2e91..f56a39bd8 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -40,7 +40,7 @@
 #include <asm/ctl_reg.h>
 #include <asm/sclp.h>
 
-pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE)));
+pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(.bss..swapper_pg_dir);
 
 unsigned long empty_zero_page, zero_page_mask;
 EXPORT_SYMBOL(empty_zero_page);
@@ -111,17 +111,16 @@ void __init paging_init(void)
 
 void mark_rodata_ro(void)
 {
-	/* Text and rodata are already protected. Nothing to do here. */
-	pr_info("Write protecting the kernel read-only data: %luk\n",
-		((unsigned long)&_eshared - (unsigned long)&_stext) >> 10);
+	unsigned long size = __end_ro_after_init - __start_ro_after_init;
+
+	set_memory_ro((unsigned long)__start_ro_after_init, size >> PAGE_SHIFT);
+	pr_info("Write protected read-only-after-init data: %luk\n", size >> 10);
 }
 
 void __init mem_init(void)
 {
-	if (MACHINE_HAS_TLB_LC)
-		cpumask_set_cpu(0, &init_mm.context.cpu_attach_mask);
+	cpumask_set_cpu(0, &init_mm.context.cpu_attach_mask);
 	cpumask_set_cpu(0, mm_cpumask(&init_mm));
-	atomic_set(&init_mm.context.attach_count, 1);
 
 	set_max_mapnr(max_low_pfn);
         high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
diff --git a/arch/s390/mm/page-states.c b/arch/s390/mm/page-states.c
index a90d45e9d..3330ea124 100644
--- a/arch/s390/mm/page-states.c
+++ b/arch/s390/mm/page-states.c
@@ -34,20 +34,25 @@ static int __init cmma(char *str)
 }
 __setup("cmma=", cmma);
 
-void __init cmma_init(void)
+static inline int cmma_test_essa(void)
 {
 	register unsigned long tmp asm("0") = 0;
 	register int rc asm("1") = -EOPNOTSUPP;
 
-	if (!cmma_flag)
-		return;
 	asm volatile(
 		"       .insn rrf,0xb9ab0000,%1,%1,0,0\n"
 		"0:     la      %0,0\n"
 		"1:\n"
 		EX_TABLE(0b,1b)
 		: "+&d" (rc), "+&d" (tmp));
-	if (rc)
+	return rc;
+}
+
+void __init cmma_init(void)
+{
+	if (!cmma_flag)
+		return;
+	if (cmma_test_essa())
 		cmma_flag = 0;
 }
 
diff --git a/arch/s390/mm/pageattr.c b/arch/s390/mm/pageattr.c
index f2a5c29a9..af7cf28cf 100644
--- a/arch/s390/mm/pageattr.c
+++ b/arch/s390/mm/pageattr.c
@@ -10,7 +10,6 @@
 #include <asm/pgtable.h>
 #include <asm/page.h>
 
-#if PAGE_DEFAULT_KEY
 static inline unsigned long sske_frame(unsigned long addr, unsigned char skey)
 {
 	asm volatile(".insn rrf,0xb22b0000,%[skey],%[addr],9,0"
@@ -22,6 +21,8 @@ void __storage_key_init_range(unsigned long start, unsigned long end)
 {
 	unsigned long boundary, size;
 
+	if (!PAGE_DEFAULT_KEY)
+		return;
 	while (start < end) {
 		if (MACHINE_HAS_EDAT1) {
 			/* set storage keys for a 1MB frame */
@@ -38,56 +39,256 @@ void __storage_key_init_range(unsigned long start, unsigned long end)
 		start += PAGE_SIZE;
 	}
 }
-#endif
 
-static pte_t *walk_page_table(unsigned long addr)
+#ifdef CONFIG_PROC_FS
+atomic_long_t direct_pages_count[PG_DIRECT_MAP_MAX];
+
+void arch_report_meminfo(struct seq_file *m)
 {
-	pgd_t *pgdp;
-	pud_t *pudp;
+	seq_printf(m, "DirectMap4k:    %8lu kB\n",
+		   atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_4K]) << 2);
+	seq_printf(m, "DirectMap1M:    %8lu kB\n",
+		   atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_1M]) << 10);
+	seq_printf(m, "DirectMap2G:    %8lu kB\n",
+		   atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_2G]) << 21);
+}
+#endif /* CONFIG_PROC_FS */
+
+static void pgt_set(unsigned long *old, unsigned long new, unsigned long addr,
+		    unsigned long dtt)
+{
+	unsigned long table, mask;
+
+	mask = 0;
+	if (MACHINE_HAS_EDAT2) {
+		switch (dtt) {
+		case CRDTE_DTT_REGION3:
+			mask = ~(PTRS_PER_PUD * sizeof(pud_t) - 1);
+			break;
+		case CRDTE_DTT_SEGMENT:
+			mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1);
+			break;
+		case CRDTE_DTT_PAGE:
+			mask = ~(PTRS_PER_PTE * sizeof(pte_t) - 1);
+			break;
+		}
+		table = (unsigned long)old & mask;
+		crdte(*old, new, table, dtt, addr, S390_lowcore.kernel_asce);
+	} else if (MACHINE_HAS_IDTE) {
+		cspg(old, *old, new);
+	} else {
+		csp((unsigned int *)old + 1, *old, new);
+	}
+}
+
+struct cpa {
+	unsigned int set_ro	: 1;
+	unsigned int clear_ro	: 1;
+};
+
+static int walk_pte_level(pmd_t *pmdp, unsigned long addr, unsigned long end,
+			  struct cpa cpa)
+{
+	pte_t *ptep, new;
+
+	ptep = pte_offset(pmdp, addr);
+	do {
+		if (pte_none(*ptep))
+			return -EINVAL;
+		if (cpa.set_ro)
+			new = pte_wrprotect(*ptep);
+		else if (cpa.clear_ro)
+			new = pte_mkwrite(pte_mkdirty(*ptep));
+		pgt_set((unsigned long *)ptep, pte_val(new), addr, CRDTE_DTT_PAGE);
+		ptep++;
+		addr += PAGE_SIZE;
+		cond_resched();
+	} while (addr < end);
+	return 0;
+}
+
+static int split_pmd_page(pmd_t *pmdp, unsigned long addr)
+{
+	unsigned long pte_addr, prot;
+	pte_t *pt_dir, *ptep;
+	pmd_t new;
+	int i, ro;
+
+	pt_dir = vmem_pte_alloc();
+	if (!pt_dir)
+		return -ENOMEM;
+	pte_addr = pmd_pfn(*pmdp) << PAGE_SHIFT;
+	ro = !!(pmd_val(*pmdp) & _SEGMENT_ENTRY_PROTECT);
+	prot = pgprot_val(ro ? PAGE_KERNEL_RO : PAGE_KERNEL);
+	ptep = pt_dir;
+	for (i = 0; i < PTRS_PER_PTE; i++) {
+		pte_val(*ptep) = pte_addr | prot;
+		pte_addr += PAGE_SIZE;
+		ptep++;
+	}
+	pmd_val(new) = __pa(pt_dir) | _SEGMENT_ENTRY;
+	pgt_set((unsigned long *)pmdp, pmd_val(new), addr, CRDTE_DTT_SEGMENT);
+	update_page_count(PG_DIRECT_MAP_4K, PTRS_PER_PTE);
+	update_page_count(PG_DIRECT_MAP_1M, -1);
+	return 0;
+}
+
+static void modify_pmd_page(pmd_t *pmdp, unsigned long addr, struct cpa cpa)
+{
+	pmd_t new;
+
+	if (cpa.set_ro)
+		new = pmd_wrprotect(*pmdp);
+	else if (cpa.clear_ro)
+		new = pmd_mkwrite(pmd_mkdirty(*pmdp));
+	pgt_set((unsigned long *)pmdp, pmd_val(new), addr, CRDTE_DTT_SEGMENT);
+}
+
+static int walk_pmd_level(pud_t *pudp, unsigned long addr, unsigned long end,
+			  struct cpa cpa)
+{
+	unsigned long next;
 	pmd_t *pmdp;
-	pte_t *ptep;
+	int rc = 0;
 
-	pgdp = pgd_offset_k(addr);
-	if (pgd_none(*pgdp))
-		return NULL;
-	pudp = pud_offset(pgdp, addr);
-	if (pud_none(*pudp) || pud_large(*pudp))
-		return NULL;
 	pmdp = pmd_offset(pudp, addr);
-	if (pmd_none(*pmdp) || pmd_large(*pmdp))
-		return NULL;
-	ptep = pte_offset_kernel(pmdp, addr);
-	if (pte_none(*ptep))
-		return NULL;
-	return ptep;
+	do {
+		if (pmd_none(*pmdp))
+			return -EINVAL;
+		next = pmd_addr_end(addr, end);
+		if (pmd_large(*pmdp)) {
+			if (addr & ~PMD_MASK || addr + PMD_SIZE > next) {
+				rc = split_pmd_page(pmdp, addr);
+				if (rc)
+					return rc;
+				continue;
+			}
+			modify_pmd_page(pmdp, addr, cpa);
+		} else {
+			rc = walk_pte_level(pmdp, addr, next, cpa);
+			if (rc)
+				return rc;
+		}
+		pmdp++;
+		addr = next;
+		cond_resched();
+	} while (addr < end);
+	return rc;
 }
 
-static void change_page_attr(unsigned long addr, int numpages,
-			     pte_t (*set) (pte_t))
+static int split_pud_page(pud_t *pudp, unsigned long addr)
 {
-	pte_t *ptep;
-	int i;
+	unsigned long pmd_addr, prot;
+	pmd_t *pm_dir, *pmdp;
+	pud_t new;
+	int i, ro;
 
-	for (i = 0; i < numpages; i++) {
-		ptep = walk_page_table(addr);
-		if (WARN_ON_ONCE(!ptep))
-			break;
-		*ptep = set(*ptep);
-		addr += PAGE_SIZE;
+	pm_dir = vmem_pmd_alloc();
+	if (!pm_dir)
+		return -ENOMEM;
+	pmd_addr = pud_pfn(*pudp) << PAGE_SHIFT;
+	ro = !!(pud_val(*pudp) & _REGION_ENTRY_PROTECT);
+	prot = pgprot_val(ro ? SEGMENT_KERNEL_RO : SEGMENT_KERNEL);
+	pmdp = pm_dir;
+	for (i = 0; i < PTRS_PER_PMD; i++) {
+		pmd_val(*pmdp) = pmd_addr | prot;
+		pmd_addr += PMD_SIZE;
+		pmdp++;
 	}
-	__tlb_flush_kernel();
+	pud_val(new) = __pa(pm_dir) | _REGION3_ENTRY;
+	pgt_set((unsigned long *)pudp, pud_val(new), addr, CRDTE_DTT_REGION3);
+	update_page_count(PG_DIRECT_MAP_1M, PTRS_PER_PMD);
+	update_page_count(PG_DIRECT_MAP_2G, -1);
+	return 0;
+}
+
+static void modify_pud_page(pud_t *pudp, unsigned long addr, struct cpa cpa)
+{
+	pud_t new;
+
+	if (cpa.set_ro)
+		new = pud_wrprotect(*pudp);
+	else if (cpa.clear_ro)
+		new = pud_mkwrite(pud_mkdirty(*pudp));
+	pgt_set((unsigned long *)pudp, pud_val(new), addr, CRDTE_DTT_REGION3);
+}
+
+static int walk_pud_level(pgd_t *pgd, unsigned long addr, unsigned long end,
+			  struct cpa cpa)
+{
+	unsigned long next;
+	pud_t *pudp;
+	int rc = 0;
+
+	pudp = pud_offset(pgd, addr);
+	do {
+		if (pud_none(*pudp))
+			return -EINVAL;
+		next = pud_addr_end(addr, end);
+		if (pud_large(*pudp)) {
+			if (addr & ~PUD_MASK || addr + PUD_SIZE > next) {
+				rc = split_pud_page(pudp, addr);
+				if (rc)
+					break;
+				continue;
+			}
+			modify_pud_page(pudp, addr, cpa);
+		} else {
+			rc = walk_pmd_level(pudp, addr, next, cpa);
+		}
+		pudp++;
+		addr = next;
+		cond_resched();
+	} while (addr < end && !rc);
+	return rc;
+}
+
+static DEFINE_MUTEX(cpa_mutex);
+
+static int change_page_attr(unsigned long addr, unsigned long end,
+			    struct cpa cpa)
+{
+	unsigned long next;
+	int rc = -EINVAL;
+	pgd_t *pgdp;
+
+	if (addr == end)
+		return 0;
+	if (end >= MODULES_END)
+		return -EINVAL;
+	mutex_lock(&cpa_mutex);
+	pgdp = pgd_offset_k(addr);
+	do {
+		if (pgd_none(*pgdp))
+			break;
+		next = pgd_addr_end(addr, end);
+		rc = walk_pud_level(pgdp, addr, next, cpa);
+		if (rc)
+			break;
+		cond_resched();
+	} while (pgdp++, addr = next, addr < end && !rc);
+	mutex_unlock(&cpa_mutex);
+	return rc;
 }
 
 int set_memory_ro(unsigned long addr, int numpages)
 {
-	change_page_attr(addr, numpages, pte_wrprotect);
-	return 0;
+	struct cpa cpa = {
+		.set_ro = 1,
+	};
+
+	addr &= PAGE_MASK;
+	return change_page_attr(addr, addr + numpages * PAGE_SIZE, cpa);
 }
 
 int set_memory_rw(unsigned long addr, int numpages)
 {
-	change_page_attr(addr, numpages, pte_mkwrite);
-	return 0;
+	struct cpa cpa = {
+		.clear_ro = 1,
+	};
+
+	addr &= PAGE_MASK;
+	return change_page_attr(addr, addr + numpages * PAGE_SIZE, cpa);
 }
 
 /* not possible */
@@ -138,7 +339,7 @@ void __kernel_map_pages(struct page *page, int numpages, int enable)
 		nr = min(numpages - i, nr);
 		if (enable) {
 			for (j = 0; j < nr; j++) {
-				pte_val(*pte) = __pa(address);
+				pte_val(*pte) = address | pgprot_val(PAGE_KERNEL);
 				address += PAGE_SIZE;
 				pte++;
 			}
diff --git a/arch/s390/mm/pgalloc.c b/arch/s390/mm/pgalloc.c
index e2565d2d0..995f78532 100644
--- a/arch/s390/mm/pgalloc.c
+++ b/arch/s390/mm/pgalloc.c
@@ -137,6 +137,29 @@ static inline unsigned int atomic_xor_bits(atomic_t *v, unsigned int bits)
 	return new;
 }
 
+#ifdef CONFIG_PGSTE
+
+struct page *page_table_alloc_pgste(struct mm_struct *mm)
+{
+	struct page *page;
+	unsigned long *table;
+
+	page = alloc_page(GFP_KERNEL|__GFP_REPEAT);
+	if (page) {
+		table = (unsigned long *) page_to_phys(page);
+		clear_table(table, _PAGE_INVALID, PAGE_SIZE/2);
+		clear_table(table + PTRS_PER_PTE, 0, PAGE_SIZE/2);
+	}
+	return page;
+}
+
+void page_table_free_pgste(struct page *page)
+{
+	__free_page(page);
+}
+
+#endif /* CONFIG_PGSTE */
+
 /*
  * page table entry allocation/free routines.
  */
@@ -149,7 +172,7 @@ unsigned long *page_table_alloc(struct mm_struct *mm)
 	/* Try to get a fragment of a 4K page as a 2K page table */
 	if (!mm_alloc_pgste(mm)) {
 		table = NULL;
-		spin_lock_bh(&mm->context.list_lock);
+		spin_lock_bh(&mm->context.pgtable_lock);
 		if (!list_empty(&mm->context.pgtable_list)) {
 			page = list_first_entry(&mm->context.pgtable_list,
 						struct page, lru);
@@ -164,7 +187,7 @@ unsigned long *page_table_alloc(struct mm_struct *mm)
 				list_del(&page->lru);
 			}
 		}
-		spin_unlock_bh(&mm->context.list_lock);
+		spin_unlock_bh(&mm->context.pgtable_lock);
 		if (table)
 			return table;
 	}
@@ -187,9 +210,9 @@ unsigned long *page_table_alloc(struct mm_struct *mm)
 		/* Return the first 2K fragment of the page */
 		atomic_set(&page->_mapcount, 1);
 		clear_table(table, _PAGE_INVALID, PAGE_SIZE);
-		spin_lock_bh(&mm->context.list_lock);
+		spin_lock_bh(&mm->context.pgtable_lock);
 		list_add(&page->lru, &mm->context.pgtable_list);
-		spin_unlock_bh(&mm->context.list_lock);
+		spin_unlock_bh(&mm->context.pgtable_lock);
 	}
 	return table;
 }
@@ -203,13 +226,13 @@ void page_table_free(struct mm_struct *mm, unsigned long *table)
 	if (!mm_alloc_pgste(mm)) {
 		/* Free 2K page table fragment of a 4K page */
 		bit = (__pa(table) & ~PAGE_MASK)/(PTRS_PER_PTE*sizeof(pte_t));
-		spin_lock_bh(&mm->context.list_lock);
+		spin_lock_bh(&mm->context.pgtable_lock);
 		mask = atomic_xor_bits(&page->_mapcount, 1U << bit);
 		if (mask & 3)
 			list_add(&page->lru, &mm->context.pgtable_list);
 		else
 			list_del(&page->lru);
-		spin_unlock_bh(&mm->context.list_lock);
+		spin_unlock_bh(&mm->context.pgtable_lock);
 		if (mask != 0)
 			return;
 	}
@@ -235,13 +258,13 @@ void page_table_free_rcu(struct mmu_gather *tlb, unsigned long *table,
 		return;
 	}
 	bit = (__pa(table) & ~PAGE_MASK) / (PTRS_PER_PTE*sizeof(pte_t));
-	spin_lock_bh(&mm->context.list_lock);
+	spin_lock_bh(&mm->context.pgtable_lock);
 	mask = atomic_xor_bits(&page->_mapcount, 0x11U << bit);
 	if (mask & 3)
 		list_add_tail(&page->lru, &mm->context.pgtable_list);
 	else
 		list_del(&page->lru);
-	spin_unlock_bh(&mm->context.list_lock);
+	spin_unlock_bh(&mm->context.pgtable_lock);
 	table = (unsigned long *) (__pa(table) | (1U << bit));
 	tlb_remove_table(tlb, table);
 }
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index ebb4f8711..5f092015a 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -27,40 +27,37 @@
 static inline pte_t ptep_flush_direct(struct mm_struct *mm,
 				      unsigned long addr, pte_t *ptep)
 {
-	int active, count;
 	pte_t old;
 
 	old = *ptep;
 	if (unlikely(pte_val(old) & _PAGE_INVALID))
 		return old;
-	active = (mm == current->active_mm) ? 1 : 0;
-	count = atomic_add_return(0x10000, &mm->context.attach_count);
-	if (MACHINE_HAS_TLB_LC && (count & 0xffff) <= active &&
+	atomic_inc(&mm->context.flush_count);
+	if (MACHINE_HAS_TLB_LC &&
 	    cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id())))
 		__ptep_ipte_local(addr, ptep);
 	else
 		__ptep_ipte(addr, ptep);
-	atomic_sub(0x10000, &mm->context.attach_count);
+	atomic_dec(&mm->context.flush_count);
 	return old;
 }
 
 static inline pte_t ptep_flush_lazy(struct mm_struct *mm,
 				    unsigned long addr, pte_t *ptep)
 {
-	int active, count;
 	pte_t old;
 
 	old = *ptep;
 	if (unlikely(pte_val(old) & _PAGE_INVALID))
 		return old;
-	active = (mm == current->active_mm) ? 1 : 0;
-	count = atomic_add_return(0x10000, &mm->context.attach_count);
-	if ((count & 0xffff) <= active) {
+	atomic_inc(&mm->context.flush_count);
+	if (cpumask_equal(&mm->context.cpu_attach_mask,
+			  cpumask_of(smp_processor_id()))) {
 		pte_val(*ptep) |= _PAGE_INVALID;
 		mm->context.flush_mm = 1;
 	} else
 		__ptep_ipte(addr, ptep);
-	atomic_sub(0x10000, &mm->context.attach_count);
+	atomic_dec(&mm->context.flush_count);
 	return old;
 }
 
@@ -70,7 +67,6 @@ static inline pgste_t pgste_get_lock(pte_t *ptep)
 #ifdef CONFIG_PGSTE
 	unsigned long old;
 
-	preempt_disable();
 	asm(
 		"	lg	%0,%2\n"
 		"0:	lgr	%1,%0\n"
@@ -93,7 +89,6 @@ static inline void pgste_set_unlock(pte_t *ptep, pgste_t pgste)
 		: "=Q" (ptep[PTRS_PER_PTE])
 		: "d" (pgste_val(pgste)), "Q" (ptep[PTRS_PER_PTE])
 		: "cc", "memory");
-	preempt_enable();
 #endif
 }
 
@@ -179,14 +174,17 @@ static inline pgste_t pgste_set_pte(pte_t *ptep, pgste_t pgste, pte_t entry)
 	return pgste;
 }
 
-static inline pgste_t pgste_ipte_notify(struct mm_struct *mm,
-					unsigned long addr,
-					pte_t *ptep, pgste_t pgste)
+static inline pgste_t pgste_pte_notify(struct mm_struct *mm,
+				       unsigned long addr,
+				       pte_t *ptep, pgste_t pgste)
 {
 #ifdef CONFIG_PGSTE
-	if (pgste_val(pgste) & PGSTE_IN_BIT) {
-		pgste_val(pgste) &= ~PGSTE_IN_BIT;
-		ptep_notify(mm, addr, ptep);
+	unsigned long bits;
+
+	bits = pgste_val(pgste) & (PGSTE_IN_BIT | PGSTE_VSIE_BIT);
+	if (bits) {
+		pgste_val(pgste) ^= bits;
+		ptep_notify(mm, addr, ptep, bits);
 	}
 #endif
 	return pgste;
@@ -199,7 +197,7 @@ static inline pgste_t ptep_xchg_start(struct mm_struct *mm,
 
 	if (mm_has_pgste(mm)) {
 		pgste = pgste_get_lock(ptep);
-		pgste = pgste_ipte_notify(mm, addr, ptep, pgste);
+		pgste = pgste_pte_notify(mm, addr, ptep, pgste);
 	}
 	return pgste;
 }
@@ -230,9 +228,11 @@ pte_t ptep_xchg_direct(struct mm_struct *mm, unsigned long addr,
 	pgste_t pgste;
 	pte_t old;
 
+	preempt_disable();
 	pgste = ptep_xchg_start(mm, addr, ptep);
 	old = ptep_flush_direct(mm, addr, ptep);
 	ptep_xchg_commit(mm, addr, ptep, pgste, old, new);
+	preempt_enable();
 	return old;
 }
 EXPORT_SYMBOL(ptep_xchg_direct);
@@ -243,9 +243,11 @@ pte_t ptep_xchg_lazy(struct mm_struct *mm, unsigned long addr,
 	pgste_t pgste;
 	pte_t old;
 
+	preempt_disable();
 	pgste = ptep_xchg_start(mm, addr, ptep);
 	old = ptep_flush_lazy(mm, addr, ptep);
 	ptep_xchg_commit(mm, addr, ptep, pgste, old, new);
+	preempt_enable();
 	return old;
 }
 EXPORT_SYMBOL(ptep_xchg_lazy);
@@ -256,6 +258,7 @@ pte_t ptep_modify_prot_start(struct mm_struct *mm, unsigned long addr,
 	pgste_t pgste;
 	pte_t old;
 
+	preempt_disable();
 	pgste = ptep_xchg_start(mm, addr, ptep);
 	old = ptep_flush_lazy(mm, addr, ptep);
 	if (mm_has_pgste(mm)) {
@@ -279,13 +282,13 @@ void ptep_modify_prot_commit(struct mm_struct *mm, unsigned long addr,
 	} else {
 		*ptep = pte;
 	}
+	preempt_enable();
 }
 EXPORT_SYMBOL(ptep_modify_prot_commit);
 
 static inline pmd_t pmdp_flush_direct(struct mm_struct *mm,
 				      unsigned long addr, pmd_t *pmdp)
 {
-	int active, count;
 	pmd_t old;
 
 	old = *pmdp;
@@ -295,36 +298,34 @@ static inline pmd_t pmdp_flush_direct(struct mm_struct *mm,
 		__pmdp_csp(pmdp);
 		return old;
 	}
-	active = (mm == current->active_mm) ? 1 : 0;
-	count = atomic_add_return(0x10000, &mm->context.attach_count);
-	if (MACHINE_HAS_TLB_LC && (count & 0xffff) <= active &&
+	atomic_inc(&mm->context.flush_count);
+	if (MACHINE_HAS_TLB_LC &&
 	    cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id())))
 		__pmdp_idte_local(addr, pmdp);
 	else
 		__pmdp_idte(addr, pmdp);
-	atomic_sub(0x10000, &mm->context.attach_count);
+	atomic_dec(&mm->context.flush_count);
 	return old;
 }
 
 static inline pmd_t pmdp_flush_lazy(struct mm_struct *mm,
 				    unsigned long addr, pmd_t *pmdp)
 {
-	int active, count;
 	pmd_t old;
 
 	old = *pmdp;
 	if (pmd_val(old) & _SEGMENT_ENTRY_INVALID)
 		return old;
-	active = (mm == current->active_mm) ? 1 : 0;
-	count = atomic_add_return(0x10000, &mm->context.attach_count);
-	if ((count & 0xffff) <= active) {
+	atomic_inc(&mm->context.flush_count);
+	if (cpumask_equal(&mm->context.cpu_attach_mask,
+			  cpumask_of(smp_processor_id()))) {
 		pmd_val(*pmdp) |= _SEGMENT_ENTRY_INVALID;
 		mm->context.flush_mm = 1;
 	} else if (MACHINE_HAS_IDTE)
 		__pmdp_idte(addr, pmdp);
 	else
 		__pmdp_csp(pmdp);
-	atomic_sub(0x10000, &mm->context.attach_count);
+	atomic_dec(&mm->context.flush_count);
 	return old;
 }
 
@@ -333,8 +334,10 @@ pmd_t pmdp_xchg_direct(struct mm_struct *mm, unsigned long addr,
 {
 	pmd_t old;
 
+	preempt_disable();
 	old = pmdp_flush_direct(mm, addr, pmdp);
 	*pmdp = new;
+	preempt_enable();
 	return old;
 }
 EXPORT_SYMBOL(pmdp_xchg_direct);
@@ -344,12 +347,53 @@ pmd_t pmdp_xchg_lazy(struct mm_struct *mm, unsigned long addr,
 {
 	pmd_t old;
 
+	preempt_disable();
 	old = pmdp_flush_lazy(mm, addr, pmdp);
 	*pmdp = new;
+	preempt_enable();
 	return old;
 }
 EXPORT_SYMBOL(pmdp_xchg_lazy);
 
+static inline pud_t pudp_flush_direct(struct mm_struct *mm,
+				      unsigned long addr, pud_t *pudp)
+{
+	pud_t old;
+
+	old = *pudp;
+	if (pud_val(old) & _REGION_ENTRY_INVALID)
+		return old;
+	if (!MACHINE_HAS_IDTE) {
+		/*
+		 * Invalid bit position is the same for pmd and pud, so we can
+		 * re-use _pmd_csp() here
+		 */
+		__pmdp_csp((pmd_t *) pudp);
+		return old;
+	}
+	atomic_inc(&mm->context.flush_count);
+	if (MACHINE_HAS_TLB_LC &&
+	    cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id())))
+		__pudp_idte_local(addr, pudp);
+	else
+		__pudp_idte(addr, pudp);
+	atomic_dec(&mm->context.flush_count);
+	return old;
+}
+
+pud_t pudp_xchg_direct(struct mm_struct *mm, unsigned long addr,
+		       pud_t *pudp, pud_t new)
+{
+	pud_t old;
+
+	preempt_disable();
+	old = pudp_flush_direct(mm, addr, pudp);
+	*pudp = new;
+	preempt_enable();
+	return old;
+}
+EXPORT_SYMBOL(pudp_xchg_direct);
+
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
 				pgtable_t pgtable)
@@ -398,20 +442,108 @@ void ptep_set_pte_at(struct mm_struct *mm, unsigned long addr,
 	pgste_t pgste;
 
 	/* the mm_has_pgste() check is done in set_pte_at() */
+	preempt_disable();
 	pgste = pgste_get_lock(ptep);
 	pgste_val(pgste) &= ~_PGSTE_GPS_ZERO;
 	pgste_set_key(ptep, pgste, entry, mm);
 	pgste = pgste_set_pte(ptep, pgste, entry);
 	pgste_set_unlock(ptep, pgste);
+	preempt_enable();
 }
 
 void ptep_set_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 {
 	pgste_t pgste;
 
+	preempt_disable();
 	pgste = pgste_get_lock(ptep);
 	pgste_val(pgste) |= PGSTE_IN_BIT;
 	pgste_set_unlock(ptep, pgste);
+	preempt_enable();
+}
+
+/**
+ * ptep_force_prot - change access rights of a locked pte
+ * @mm: pointer to the process mm_struct
+ * @addr: virtual address in the guest address space
+ * @ptep: pointer to the page table entry
+ * @prot: indicates guest access rights: PROT_NONE, PROT_READ or PROT_WRITE
+ * @bit: pgste bit to set (e.g. for notification)
+ *
+ * Returns 0 if the access rights were changed and -EAGAIN if the current
+ * and requested access rights are incompatible.
+ */
+int ptep_force_prot(struct mm_struct *mm, unsigned long addr,
+		    pte_t *ptep, int prot, unsigned long bit)
+{
+	pte_t entry;
+	pgste_t pgste;
+	int pte_i, pte_p;
+
+	pgste = pgste_get_lock(ptep);
+	entry = *ptep;
+	/* Check pte entry after all locks have been acquired */
+	pte_i = pte_val(entry) & _PAGE_INVALID;
+	pte_p = pte_val(entry) & _PAGE_PROTECT;
+	if ((pte_i && (prot != PROT_NONE)) ||
+	    (pte_p && (prot & PROT_WRITE))) {
+		pgste_set_unlock(ptep, pgste);
+		return -EAGAIN;
+	}
+	/* Change access rights and set pgste bit */
+	if (prot == PROT_NONE && !pte_i) {
+		ptep_flush_direct(mm, addr, ptep);
+		pgste = pgste_update_all(entry, pgste, mm);
+		pte_val(entry) |= _PAGE_INVALID;
+	}
+	if (prot == PROT_READ && !pte_p) {
+		ptep_flush_direct(mm, addr, ptep);
+		pte_val(entry) &= ~_PAGE_INVALID;
+		pte_val(entry) |= _PAGE_PROTECT;
+	}
+	pgste_val(pgste) |= bit;
+	pgste = pgste_set_pte(ptep, pgste, entry);
+	pgste_set_unlock(ptep, pgste);
+	return 0;
+}
+
+int ptep_shadow_pte(struct mm_struct *mm, unsigned long saddr,
+		    pte_t *sptep, pte_t *tptep, pte_t pte)
+{
+	pgste_t spgste, tpgste;
+	pte_t spte, tpte;
+	int rc = -EAGAIN;
+
+	if (!(pte_val(*tptep) & _PAGE_INVALID))
+		return 0;	/* already shadowed */
+	spgste = pgste_get_lock(sptep);
+	spte = *sptep;
+	if (!(pte_val(spte) & _PAGE_INVALID) &&
+	    !((pte_val(spte) & _PAGE_PROTECT) &&
+	      !(pte_val(pte) & _PAGE_PROTECT))) {
+		pgste_val(spgste) |= PGSTE_VSIE_BIT;
+		tpgste = pgste_get_lock(tptep);
+		pte_val(tpte) = (pte_val(spte) & PAGE_MASK) |
+				(pte_val(pte) & _PAGE_PROTECT);
+		/* don't touch the storage key - it belongs to parent pgste */
+		tpgste = pgste_set_pte(tptep, tpgste, tpte);
+		pgste_set_unlock(tptep, tpgste);
+		rc = 1;
+	}
+	pgste_set_unlock(sptep, spgste);
+	return rc;
+}
+
+void ptep_unshadow_pte(struct mm_struct *mm, unsigned long saddr, pte_t *ptep)
+{
+	pgste_t pgste;
+
+	pgste = pgste_get_lock(ptep);
+	/* notifier is called by the caller */
+	ptep_flush_direct(mm, saddr, ptep);
+	/* don't touch the storage key - it belongs to parent pgste */
+	pgste = pgste_set_pte(ptep, pgste, __pte(_PAGE_INVALID));
+	pgste_set_unlock(ptep, pgste);
 }
 
 static void ptep_zap_swap_entry(struct mm_struct *mm, swp_entry_t entry)
@@ -434,6 +566,7 @@ void ptep_zap_unused(struct mm_struct *mm, unsigned long addr,
 	pte_t pte;
 
 	/* Zap unused and logically-zero pages */
+	preempt_disable();
 	pgste = pgste_get_lock(ptep);
 	pgstev = pgste_val(pgste);
 	pte = *ptep;
@@ -446,6 +579,7 @@ void ptep_zap_unused(struct mm_struct *mm, unsigned long addr,
 	if (reset)
 		pgste_val(pgste) &= ~_PGSTE_GPS_USAGE_MASK;
 	pgste_set_unlock(ptep, pgste);
+	preempt_enable();
 }
 
 void ptep_zap_key(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
@@ -454,6 +588,7 @@ void ptep_zap_key(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 	pgste_t pgste;
 
 	/* Clear storage key */
+	preempt_disable();
 	pgste = pgste_get_lock(ptep);
 	pgste_val(pgste) &= ~(PGSTE_ACC_BITS | PGSTE_FP_BIT |
 			      PGSTE_GR_BIT | PGSTE_GC_BIT);
@@ -461,6 +596,7 @@ void ptep_zap_key(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 	if (!(ptev & _PAGE_INVALID) && (ptev & _PAGE_WRITE))
 		page_set_storage_key(ptev & PAGE_MASK, PAGE_DEFAULT_KEY, 1);
 	pgste_set_unlock(ptep, pgste);
+	preempt_enable();
 }
 
 /*
@@ -483,7 +619,7 @@ bool test_and_clear_guest_dirty(struct mm_struct *mm, unsigned long addr)
 	pgste_val(pgste) &= ~PGSTE_UC_BIT;
 	pte = *ptep;
 	if (dirty && (pte_val(pte) & _PAGE_PRESENT)) {
-		pgste = pgste_ipte_notify(mm, addr, ptep, pgste);
+		pgste = pgste_pte_notify(mm, addr, ptep, pgste);
 		__ptep_ipte(addr, ptep);
 		if (MACHINE_HAS_ESOP || !(pte_val(pte) & _PAGE_WRITE))
 			pte_val(pte) |= _PAGE_PROTECT;
@@ -506,12 +642,9 @@ int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
 	pgste_t old, new;
 	pte_t *ptep;
 
-	down_read(&mm->mmap_sem);
 	ptep = get_locked_pte(mm, addr, &ptl);
-	if (unlikely(!ptep)) {
-		up_read(&mm->mmap_sem);
+	if (unlikely(!ptep))
 		return -EFAULT;
-	}
 
 	new = old = pgste_get_lock(ptep);
 	pgste_val(new) &= ~(PGSTE_GR_BIT | PGSTE_GC_BIT |
@@ -538,45 +671,100 @@ int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
 
 	pgste_set_unlock(ptep, new);
 	pte_unmap_unlock(ptep, ptl);
-	up_read(&mm->mmap_sem);
 	return 0;
 }
 EXPORT_SYMBOL(set_guest_storage_key);
 
-unsigned long get_guest_storage_key(struct mm_struct *mm, unsigned long addr)
+/**
+ * Conditionally set a guest storage key (handling csske).
+ * oldkey will be updated when either mr or mc is set and a pointer is given.
+ *
+ * Returns 0 if a guests storage key update wasn't necessary, 1 if the guest
+ * storage key was updated and -EFAULT on access errors.
+ */
+int cond_set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
+			       unsigned char key, unsigned char *oldkey,
+			       bool nq, bool mr, bool mc)
+{
+	unsigned char tmp, mask = _PAGE_ACC_BITS | _PAGE_FP_BIT;
+	int rc;
+
+	/* we can drop the pgste lock between getting and setting the key */
+	if (mr | mc) {
+		rc = get_guest_storage_key(current->mm, addr, &tmp);
+		if (rc)
+			return rc;
+		if (oldkey)
+			*oldkey = tmp;
+		if (!mr)
+			mask |= _PAGE_REFERENCED;
+		if (!mc)
+			mask |= _PAGE_CHANGED;
+		if (!((tmp ^ key) & mask))
+			return 0;
+	}
+	rc = set_guest_storage_key(current->mm, addr, key, nq);
+	return rc < 0 ? rc : 1;
+}
+EXPORT_SYMBOL(cond_set_guest_storage_key);
+
+/**
+ * Reset a guest reference bit (rrbe), returning the reference and changed bit.
+ *
+ * Returns < 0 in case of error, otherwise the cc to be reported to the guest.
+ */
+int reset_guest_reference_bit(struct mm_struct *mm, unsigned long addr)
 {
-	unsigned char key;
 	spinlock_t *ptl;
-	pgste_t pgste;
+	pgste_t old, new;
 	pte_t *ptep;
+	int cc = 0;
 
-	down_read(&mm->mmap_sem);
 	ptep = get_locked_pte(mm, addr, &ptl);
-	if (unlikely(!ptep)) {
-		up_read(&mm->mmap_sem);
+	if (unlikely(!ptep))
 		return -EFAULT;
-	}
-	pgste = pgste_get_lock(ptep);
 
-	if (pte_val(*ptep) & _PAGE_INVALID) {
-		key  = (pgste_val(pgste) & PGSTE_ACC_BITS) >> 56;
-		key |= (pgste_val(pgste) & PGSTE_FP_BIT) >> 56;
-		key |= (pgste_val(pgste) & PGSTE_GR_BIT) >> 48;
-		key |= (pgste_val(pgste) & PGSTE_GC_BIT) >> 48;
-	} else {
-		key = page_get_storage_key(pte_val(*ptep) & PAGE_MASK);
+	new = old = pgste_get_lock(ptep);
+	/* Reset guest reference bit only */
+	pgste_val(new) &= ~PGSTE_GR_BIT;
 
-		/* Reflect guest's logical view, not physical */
-		if (pgste_val(pgste) & PGSTE_GR_BIT)
-			key |= _PAGE_REFERENCED;
-		if (pgste_val(pgste) & PGSTE_GC_BIT)
-			key |= _PAGE_CHANGED;
+	if (!(pte_val(*ptep) & _PAGE_INVALID)) {
+		cc = page_reset_referenced(pte_val(*ptep) & PAGE_MASK);
+		/* Merge real referenced bit into host-set */
+		pgste_val(new) |= ((unsigned long) cc << 53) & PGSTE_HR_BIT;
 	}
+	/* Reflect guest's logical view, not physical */
+	cc |= (pgste_val(old) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 49;
+	/* Changing the guest storage key is considered a change of the page */
+	if ((pgste_val(new) ^ pgste_val(old)) & PGSTE_GR_BIT)
+		pgste_val(new) |= PGSTE_UC_BIT;
+
+	pgste_set_unlock(ptep, new);
+	pte_unmap_unlock(ptep, ptl);
+	return 0;
+}
+EXPORT_SYMBOL(reset_guest_reference_bit);
+
+int get_guest_storage_key(struct mm_struct *mm, unsigned long addr,
+			  unsigned char *key)
+{
+	spinlock_t *ptl;
+	pgste_t pgste;
+	pte_t *ptep;
 
+	ptep = get_locked_pte(mm, addr, &ptl);
+	if (unlikely(!ptep))
+		return -EFAULT;
+
+	pgste = pgste_get_lock(ptep);
+	*key = (pgste_val(pgste) & (PGSTE_ACC_BITS | PGSTE_FP_BIT)) >> 56;
+	if (!(pte_val(*ptep) & _PAGE_INVALID))
+		*key = page_get_storage_key(pte_val(*ptep) & PAGE_MASK);
+	/* Reflect guest's logical view, not physical */
+	*key |= (pgste_val(pgste) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 48;
 	pgste_set_unlock(ptep, pgste);
 	pte_unmap_unlock(ptep, ptl);
-	up_read(&mm->mmap_sem);
-	return key;
+	return 0;
 }
 EXPORT_SYMBOL(get_guest_storage_key);
 #endif
diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c
index d48cf25cf..184829276 100644
--- a/arch/s390/mm/vmem.c
+++ b/arch/s390/mm/vmem.c
@@ -11,6 +11,7 @@
 #include <linux/hugetlb.h>
 #include <linux/slab.h>
 #include <linux/memblock.h>
+#include <asm/cacheflush.h>
 #include <asm/pgalloc.h>
 #include <asm/pgtable.h>
 #include <asm/setup.h>
@@ -29,9 +30,11 @@ static LIST_HEAD(mem_segs);
 
 static void __ref *vmem_alloc_pages(unsigned int order)
 {
+	unsigned long size = PAGE_SIZE << order;
+
 	if (slab_is_available())
 		return (void *)__get_free_pages(GFP_KERNEL, order);
-	return alloc_bootmem_pages((1 << order) * PAGE_SIZE);
+	return alloc_bootmem_align(size, size);
 }
 
 static inline pud_t *vmem_pud_alloc(void)
@@ -45,7 +48,7 @@ static inline pud_t *vmem_pud_alloc(void)
 	return pud;
 }
 
-static inline pmd_t *vmem_pmd_alloc(void)
+pmd_t *vmem_pmd_alloc(void)
 {
 	pmd_t *pmd = NULL;
 
@@ -56,7 +59,7 @@ static inline pmd_t *vmem_pmd_alloc(void)
 	return pmd;
 }
 
-static pte_t __ref *vmem_pte_alloc(void)
+pte_t __ref *vmem_pte_alloc(void)
 {
 	pte_t *pte;
 
@@ -75,8 +78,9 @@ static pte_t __ref *vmem_pte_alloc(void)
 /*
  * Add a physical memory range to the 1:1 mapping.
  */
-static int vmem_add_mem(unsigned long start, unsigned long size, int ro)
+static int vmem_add_mem(unsigned long start, unsigned long size)
 {
+	unsigned long pages4k, pages1m, pages2g;
 	unsigned long end = start + size;
 	unsigned long address = start;
 	pgd_t *pg_dir;
@@ -85,6 +89,7 @@ static int vmem_add_mem(unsigned long start, unsigned long size, int ro)
 	pte_t *pt_dir;
 	int ret = -ENOMEM;
 
+	pages4k = pages1m = pages2g = 0;
 	while (address < end) {
 		pg_dir = pgd_offset_k(address);
 		if (pgd_none(*pg_dir)) {
@@ -97,10 +102,9 @@ static int vmem_add_mem(unsigned long start, unsigned long size, int ro)
 		if (MACHINE_HAS_EDAT2 && pud_none(*pu_dir) && address &&
 		    !(address & ~PUD_MASK) && (address + PUD_SIZE <= end) &&
 		     !debug_pagealloc_enabled()) {
-			pud_val(*pu_dir) = __pa(address) |
-				_REGION_ENTRY_TYPE_R3 | _REGION3_ENTRY_LARGE |
-				(ro ? _REGION_ENTRY_PROTECT : 0);
+			pud_val(*pu_dir) = address | pgprot_val(REGION3_KERNEL);
 			address += PUD_SIZE;
+			pages2g++;
 			continue;
 		}
 		if (pud_none(*pu_dir)) {
@@ -113,11 +117,9 @@ static int vmem_add_mem(unsigned long start, unsigned long size, int ro)
 		if (MACHINE_HAS_EDAT1 && pmd_none(*pm_dir) && address &&
 		    !(address & ~PMD_MASK) && (address + PMD_SIZE <= end) &&
 		    !debug_pagealloc_enabled()) {
-			pmd_val(*pm_dir) = __pa(address) |
-				_SEGMENT_ENTRY | _SEGMENT_ENTRY_LARGE |
-				_SEGMENT_ENTRY_YOUNG |
-				(ro ? _SEGMENT_ENTRY_PROTECT : 0);
+			pmd_val(*pm_dir) = address | pgprot_val(SEGMENT_KERNEL);
 			address += PMD_SIZE;
+			pages1m++;
 			continue;
 		}
 		if (pmd_none(*pm_dir)) {
@@ -128,12 +130,15 @@ static int vmem_add_mem(unsigned long start, unsigned long size, int ro)
 		}
 
 		pt_dir = pte_offset_kernel(pm_dir, address);
-		pte_val(*pt_dir) = __pa(address) |
-			pgprot_val(ro ? PAGE_KERNEL_RO : PAGE_KERNEL);
+		pte_val(*pt_dir) = address |  pgprot_val(PAGE_KERNEL);
 		address += PAGE_SIZE;
+		pages4k++;
 	}
 	ret = 0;
 out:
+	update_page_count(PG_DIRECT_MAP_4K, pages4k);
+	update_page_count(PG_DIRECT_MAP_1M, pages1m);
+	update_page_count(PG_DIRECT_MAP_2G, pages2g);
 	return ret;
 }
 
@@ -143,15 +148,15 @@ out:
  */
 static void vmem_remove_range(unsigned long start, unsigned long size)
 {
+	unsigned long pages4k, pages1m, pages2g;
 	unsigned long end = start + size;
 	unsigned long address = start;
 	pgd_t *pg_dir;
 	pud_t *pu_dir;
 	pmd_t *pm_dir;
 	pte_t *pt_dir;
-	pte_t  pte;
 
-	pte_val(pte) = _PAGE_INVALID;
+	pages4k = pages1m = pages2g = 0;
 	while (address < end) {
 		pg_dir = pgd_offset_k(address);
 		if (pgd_none(*pg_dir)) {
@@ -166,6 +171,7 @@ static void vmem_remove_range(unsigned long start, unsigned long size)
 		if (pud_large(*pu_dir)) {
 			pud_clear(pu_dir);
 			address += PUD_SIZE;
+			pages2g++;
 			continue;
 		}
 		pm_dir = pmd_offset(pu_dir, address);
@@ -176,13 +182,18 @@ static void vmem_remove_range(unsigned long start, unsigned long size)
 		if (pmd_large(*pm_dir)) {
 			pmd_clear(pm_dir);
 			address += PMD_SIZE;
+			pages1m++;
 			continue;
 		}
 		pt_dir = pte_offset_kernel(pm_dir, address);
-		*pt_dir = pte;
+		pte_clear(&init_mm, address, pt_dir);
 		address += PAGE_SIZE;
+		pages4k++;
 	}
 	flush_tlb_kernel_range(start, end);
+	update_page_count(PG_DIRECT_MAP_4K, -pages4k);
+	update_page_count(PG_DIRECT_MAP_1M, -pages1m);
+	update_page_count(PG_DIRECT_MAP_2G, -pages2g);
 }
 
 /*
@@ -341,7 +352,7 @@ int vmem_add_mapping(unsigned long start, unsigned long size)
 	if (ret)
 		goto out_free;
 
-	ret = vmem_add_mem(start, size, 0);
+	ret = vmem_add_mem(start, size);
 	if (ret)
 		goto out_remove;
 	goto out;
@@ -362,31 +373,13 @@ out:
  */
 void __init vmem_map_init(void)
 {
-	unsigned long ro_start, ro_end;
+	unsigned long size = _eshared - _stext;
 	struct memblock_region *reg;
-	phys_addr_t start, end;
 
-	ro_start = PFN_ALIGN((unsigned long)&_stext);
-	ro_end = (unsigned long)&_eshared & PAGE_MASK;
-	for_each_memblock(memory, reg) {
-		start = reg->base;
-		end = reg->base + reg->size;
-		if (start >= ro_end || end <= ro_start)
-			vmem_add_mem(start, end - start, 0);
-		else if (start >= ro_start && end <= ro_end)
-			vmem_add_mem(start, end - start, 1);
-		else if (start >= ro_start) {
-			vmem_add_mem(start, ro_end - start, 1);
-			vmem_add_mem(ro_end, end - ro_end, 0);
-		} else if (end < ro_end) {
-			vmem_add_mem(start, ro_start - start, 0);
-			vmem_add_mem(ro_start, end - ro_start, 1);
-		} else {
-			vmem_add_mem(start, ro_start - start, 0);
-			vmem_add_mem(ro_start, ro_end - ro_start, 1);
-			vmem_add_mem(ro_end, end - ro_end, 0);
-		}
-	}
+	for_each_memblock(memory, reg)
+		vmem_add_mem(reg->base, reg->size);
+	set_memory_ro((unsigned long)_stext, size >> PAGE_SHIFT);
+	pr_info("Write protected kernel read-only data: %luk\n", size >> 10);
 }
 
 /*