radix-tree: rewrite radix_tree_tag_set

Use the new multi-order support functions to rewrite
radix_tree_tag_set()

Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Jan Kara <jack@suse.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Ross Zwisler 2016-05-20 17:02:32 -07:00 committed by Linus Torvalds
parent 643b57d0a9
commit fb969909dd
1 changed files with 17 additions and 20 deletions

View File

@ -722,35 +722,32 @@ EXPORT_SYMBOL(radix_tree_lookup);
void *radix_tree_tag_set(struct radix_tree_root *root,
unsigned long index, unsigned int tag)
{
unsigned int height, shift;
struct radix_tree_node *slot;
struct radix_tree_node *node, *parent;
unsigned long maxindex;
unsigned int shift;
height = root->height;
BUG_ON(index > radix_tree_maxindex(height));
shift = radix_tree_load_root(root, &node, &maxindex);
BUG_ON(index > maxindex);
slot = indirect_to_ptr(root->rnode);
shift = (height - 1) * RADIX_TREE_MAP_SHIFT;
while (radix_tree_is_indirect_ptr(node)) {
unsigned offset;
while (height > 0) {
int offset;
offset = (index >> shift) & RADIX_TREE_MAP_MASK;
if (!tag_get(slot, tag, offset))
tag_set(slot, tag, offset);
slot = slot->slots[offset];
BUG_ON(slot == NULL);
if (!radix_tree_is_indirect_ptr(slot))
break;
slot = indirect_to_ptr(slot);
shift -= RADIX_TREE_MAP_SHIFT;
height--;
offset = (index >> shift) & RADIX_TREE_MAP_MASK;
parent = indirect_to_ptr(node);
offset = radix_tree_descend(parent, &node, offset);
BUG_ON(!node);
if (!tag_get(parent, tag, offset))
tag_set(parent, tag, offset);
}
/* set the root's tag bit */
if (slot && !root_tag_get(root, tag))
if (!root_tag_get(root, tag))
root_tag_set(root, tag);
return slot;
return node;
}
EXPORT_SYMBOL(radix_tree_tag_set);