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authorMatthew Wilcox <willy@infradead.org>2018-05-19 16:47:47 -0400
committerMatthew Wilcox <willy@infradead.org>2018-10-21 10:46:44 -0400
commit2956c6644bfd9aab9f6b21a12e1bd75876d9dd73 (patch)
tree7044804fd7b33b00f936ae11e6cc56880996d1da /lib
parent1cf56f9d670b88b2e947a7ccdb8ba32e6477915d (diff)
downloadlinux-2956c6644bfd9aab9f6b21a12e1bd75876d9dd73.tar.gz
radix tree: Remove split/join code
radix_tree_split and radix_tree_join were never used upstream. Remove them; if they're needed in future they will be replaced by XArray equivalents. Signed-off-by: Matthew Wilcox <willy@infradead.org>
Diffstat (limited to 'lib')
-rw-r--r--lib/radix-tree.c171
1 files changed, 2 insertions, 169 deletions
diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index c4c252185734..c52e0bef5264 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -415,28 +415,6 @@ int radix_tree_maybe_preload(gfp_t gfp_mask)
}
EXPORT_SYMBOL(radix_tree_maybe_preload);
-#ifdef CONFIG_RADIX_TREE_MULTIORDER
-/*
- * Preload with enough objects to ensure that we can split a single entry
- * of order @old_order into many entries of size @new_order
- */
-int radix_tree_split_preload(unsigned int old_order, unsigned int new_order,
- gfp_t gfp_mask)
-{
- unsigned top = 1 << (old_order % RADIX_TREE_MAP_SHIFT);
- unsigned layers = (old_order / RADIX_TREE_MAP_SHIFT) -
- (new_order / RADIX_TREE_MAP_SHIFT);
- unsigned nr = 0;
-
- WARN_ON_ONCE(!gfpflags_allow_blocking(gfp_mask));
- BUG_ON(new_order >= old_order);
-
- while (layers--)
- nr = nr * RADIX_TREE_MAP_SIZE + 1;
- return __radix_tree_preload(gfp_mask, top * nr);
-}
-#endif
-
/*
* The same as function above, but preload number of nodes required to insert
* (1 << order) continuous naturally-aligned elements.
@@ -1111,8 +1089,8 @@ EXPORT_SYMBOL(radix_tree_replace_slot);
* @slot: pointer to slot
* @item: new item to store in the slot.
*
- * For use with radix_tree_split() and radix_tree_for_each_slot().
- * Caller must hold tree write locked across split and replacement.
+ * For use with radix_tree_for_each_slot().
+ * Caller must hold tree write locked.
*/
void radix_tree_iter_replace(struct radix_tree_root *root,
const struct radix_tree_iter *iter,
@@ -1121,151 +1099,6 @@ void radix_tree_iter_replace(struct radix_tree_root *root,
__radix_tree_replace(root, iter->node, slot, item);
}
-#ifdef CONFIG_RADIX_TREE_MULTIORDER
-/**
- * radix_tree_join - replace multiple entries with one multiorder entry
- * @root: radix tree root
- * @index: an index inside the new entry
- * @order: order of the new entry
- * @item: new entry
- *
- * Call this function to replace several entries with one larger entry.
- * The existing entries are presumed to not need freeing as a result of
- * this call.
- *
- * The replacement entry will have all the tags set on it that were set
- * on any of the entries it is replacing.
- */
-int radix_tree_join(struct radix_tree_root *root, unsigned long index,
- unsigned order, void *item)
-{
- struct radix_tree_node *node;
- void __rcu **slot;
- int error;
-
- BUG_ON(radix_tree_is_internal_node(item));
-
- error = __radix_tree_create(root, index, order, &node, &slot);
- if (!error)
- error = insert_entries(node, slot, item, order, true);
- if (error > 0)
- error = 0;
-
- return error;
-}
-
-/**
- * radix_tree_split - Split an entry into smaller entries
- * @root: radix tree root
- * @index: An index within the large entry
- * @order: Order of new entries
- *
- * Call this function as the first step in replacing a multiorder entry
- * with several entries of lower order. After this function returns,
- * loop over the relevant portion of the tree using radix_tree_for_each_slot()
- * and call radix_tree_iter_replace() to set up each new entry.
- *
- * The tags from this entry are replicated to all the new entries.
- *
- * The radix tree should be locked against modification during the entire
- * replacement operation. Lock-free lookups will see RADIX_TREE_RETRY which
- * should prompt RCU walkers to restart the lookup from the root.
- */
-int radix_tree_split(struct radix_tree_root *root, unsigned long index,
- unsigned order)
-{
- struct radix_tree_node *parent, *node, *child;
- void __rcu **slot;
- unsigned int offset, end;
- unsigned n, tag, tags = 0;
- gfp_t gfp = root_gfp_mask(root);
-
- if (!__radix_tree_lookup(root, index, &parent, &slot))
- return -ENOENT;
- if (!parent)
- return -ENOENT;
-
- offset = get_slot_offset(parent, slot);
-
- for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++)
- if (tag_get(parent, tag, offset))
- tags |= 1 << tag;
-
- for (end = offset + 1; end < RADIX_TREE_MAP_SIZE; end++) {
- if (!xa_is_sibling(rcu_dereference_raw(parent->slots[end])))
- break;
- for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++)
- if (tags & (1 << tag))
- tag_set(parent, tag, end);
- /* rcu_assign_pointer ensures tags are set before RETRY */
- rcu_assign_pointer(parent->slots[end], RADIX_TREE_RETRY);
- }
- rcu_assign_pointer(parent->slots[offset], RADIX_TREE_RETRY);
- parent->nr_values -= (end - offset);
-
- if (order == parent->shift)
- return 0;
- if (order > parent->shift) {
- while (offset < end)
- offset += insert_entries(parent, &parent->slots[offset],
- RADIX_TREE_RETRY, order, true);
- return 0;
- }
-
- node = parent;
-
- for (;;) {
- if (node->shift > order) {
- child = radix_tree_node_alloc(gfp, node, root,
- node->shift - RADIX_TREE_MAP_SHIFT,
- offset, 0, 0);
- if (!child)
- goto nomem;
- if (node != parent) {
- node->count++;
- rcu_assign_pointer(node->slots[offset],
- node_to_entry(child));
- for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++)
- if (tags & (1 << tag))
- tag_set(node, tag, offset);
- }
-
- node = child;
- offset = 0;
- continue;
- }
-
- n = insert_entries(node, &node->slots[offset],
- RADIX_TREE_RETRY, order, false);
- BUG_ON(n > RADIX_TREE_MAP_SIZE);
-
- for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++)
- if (tags & (1 << tag))
- tag_set(node, tag, offset);
- offset += n;
-
- while (offset == RADIX_TREE_MAP_SIZE) {
- if (node == parent)
- break;
- offset = node->offset;
- child = node;
- node = node->parent;
- rcu_assign_pointer(node->slots[offset],
- node_to_entry(child));
- offset++;
- }
- if ((node == parent) && (offset == end))
- return 0;
- }
-
- nomem:
- /* Shouldn't happen; did user forget to preload? */
- /* TODO: free all the allocated nodes */
- WARN_ON(1);
- return -ENOMEM;
-}
-#endif
-
static void node_tag_set(struct radix_tree_root *root,
struct radix_tree_node *node,
unsigned int tag, unsigned int offset)