Merge branch 'akpm' (patches from Andrew)

Merge more updates from Andrew Morton:

 - a few misc things

 - kexec updates

 - DMA-mapping updates to better support networking DMA operations

 - IPC updates

 - various MM changes to improve DAX fault handling

 - lots of radix-tree changes, mainly to the test suite. All leading up
   to reimplementing the IDA/IDR code to be a wrapper layer over the
   radix-tree. However the final trigger-pulling patch is held off for
   4.11.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (114 commits)
  radix tree test suite: delete unused rcupdate.c
  radix tree test suite: add new tag check
  radix-tree: ensure counts are initialised
  radix tree test suite: cache recently freed objects
  radix tree test suite: add some more functionality
  idr: reduce the number of bits per level from 8 to 6
  rxrpc: abstract away knowledge of IDR internals
  tpm: use idr_find(), not idr_find_slowpath()
  idr: add ida_is_empty
  radix tree test suite: check multiorder iteration
  radix-tree: fix replacement for multiorder entries
  radix-tree: add radix_tree_split_preload()
  radix-tree: add radix_tree_split
  radix-tree: add radix_tree_join
  radix-tree: delete radix_tree_range_tag_if_tagged()
  radix-tree: delete radix_tree_locate_item()
  radix-tree: improve multiorder iterators
  btrfs: fix race in btrfs_free_dummy_fs_info()
  radix-tree: improve dump output
  radix-tree: make radix_tree_find_next_bit more useful
  ...

1 files changed, 82 insertions, 10 deletions

diff --git a/tools/testing/radix-tree/test.c b/tools/testing/radix-tree/test.c
index a6e8099eaf4f..e5726e373646 100644
--- a/tools/testing/radix-tree/test.c
+++ b/tools/testing/radix-tree/test.c
@@ -24,21 +24,29 @@ int item_tag_get(struct radix_tree_root *root, unsigned long index, int tag)
 	return radix_tree_tag_get(root, index, tag);
 }
 
-int __item_insert(struct radix_tree_root *root, struct item *item,
-			unsigned order)
+int __item_insert(struct radix_tree_root *root, struct item *item)
 {
-	return __radix_tree_insert(root, item->index, order, item);
+	return __radix_tree_insert(root, item->index, item->order, item);
 }
 
 int item_insert(struct radix_tree_root *root, unsigned long index)
 {
-	return __item_insert(root, item_create(index), 0);
+	return __item_insert(root, item_create(index, 0));
 }
 
 int item_insert_order(struct radix_tree_root *root, unsigned long index,
 			unsigned order)
 {
-	return __item_insert(root, item_create(index), order);
+	return __item_insert(root, item_create(index, order));
+}
+
+void item_sanity(struct item *item, unsigned long index)
+{
+	unsigned long mask;
+	assert(!radix_tree_is_internal_node(item));
+	assert(item->order < BITS_PER_LONG);
+	mask = (1UL << item->order) - 1;
+	assert((item->index | mask) == (index | mask));
 }
 
 int item_delete(struct radix_tree_root *root, unsigned long index)
@@ -46,18 +54,19 @@ int item_delete(struct radix_tree_root *root, unsigned long index)
 	struct item *item = radix_tree_delete(root, index);
 
 	if (item) {
-		assert(item->index == index);
+		item_sanity(item, index);
 		free(item);
 		return 1;
 	}
 	return 0;
 }
 
-struct item *item_create(unsigned long index)
+struct item *item_create(unsigned long index, unsigned int order)
 {
 	struct item *ret = malloc(sizeof(*ret));
 
 	ret->index = index;
+	ret->order = order;
 	return ret;
 }
 
@@ -66,8 +75,8 @@ void item_check_present(struct radix_tree_root *root, unsigned long index)
 	struct item *item;
 
 	item = radix_tree_lookup(root, index);
-	assert(item != 0);
-	assert(item->index == index);
+	assert(item != NULL);
+	item_sanity(item, index);
 }
 
 struct item *item_lookup(struct radix_tree_root *root, unsigned long index)
@@ -80,7 +89,7 @@ void item_check_absent(struct radix_tree_root *root, unsigned long index)
 	struct item *item;
 
 	item = radix_tree_lookup(root, index);
-	assert(item == 0);
+	assert(item == NULL);
 }
 
 /*
@@ -142,6 +151,62 @@ void item_full_scan(struct radix_tree_root *root, unsigned long start,
 	assert(nfound == 0);
 }
 
+/* Use the same pattern as tag_pages_for_writeback() in mm/page-writeback.c */
+int tag_tagged_items(struct radix_tree_root *root, pthread_mutex_t *lock,
+			unsigned long start, unsigned long end, unsigned batch,
+			unsigned iftag, unsigned thentag)
+{
+	unsigned long tagged = 0;
+	struct radix_tree_iter iter;
+	void **slot;
+
+	if (batch == 0)
+		batch = 1;
+
+	if (lock)
+		pthread_mutex_lock(lock);
+	radix_tree_for_each_tagged(slot, root, &iter, start, iftag) {
+		if (iter.index > end)
+			break;
+		radix_tree_iter_tag_set(root, &iter, thentag);
+		tagged++;
+		if ((tagged % batch) != 0)
+			continue;
+		slot = radix_tree_iter_resume(slot, &iter);
+		if (lock) {
+			pthread_mutex_unlock(lock);
+			rcu_barrier();
+			pthread_mutex_lock(lock);
+		}
+	}
+	if (lock)
+		pthread_mutex_unlock(lock);
+
+	return tagged;
+}
+
+/* Use the same pattern as find_swap_entry() in mm/shmem.c */
+unsigned long find_item(struct radix_tree_root *root, void *item)
+{
+	struct radix_tree_iter iter;
+	void **slot;
+	unsigned long found = -1;
+	unsigned long checked = 0;
+
+	radix_tree_for_each_slot(slot, root, &iter, 0) {
+		if (*slot == item) {
+			found = iter.index;
+			break;
+		}
+		checked++;
+		if ((checked % 4) != 0)
+			continue;
+		slot = radix_tree_iter_resume(slot, &iter);
+	}
+
+	return found;
+}
+
 static int verify_node(struct radix_tree_node *slot, unsigned int tag,
 			int tagged)
 {
@@ -200,9 +265,16 @@ void verify_tag_consistency(struct radix_tree_root *root, unsigned int tag)
 
 void item_kill_tree(struct radix_tree_root *root)
 {
+	struct radix_tree_iter iter;
+	void **slot;
 	struct item *items[32];
 	int nfound;
 
+	radix_tree_for_each_slot(slot, root, &iter, 0) {
+		if (radix_tree_exceptional_entry(*slot))
+			radix_tree_delete(root, iter.index);
+	}
+
 	while ((nfound = radix_tree_gang_lookup(root, (void **)items, 0, 32))) {
 		int i;