btrfs: clean up NULL checks in qgroup_unreserve_range() (f07728d5) · Commits · 戴 / test

Smatch complains that this code dereferences "entry" before checking whether it's NULL on the next line. Fortunately, rb_entry() will never return NULL so it doesn't cause a problem. We can clean up the NULL checking a bit to silence the warning and make the code more clear. Reviewed-by:

Qu Wenruo <wqu@suse.com> Signed-off-by:

Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by:

David Sterba <dsterba@suse.com> Signed-off-by:

David Sterba <dsterba@suse.com>

fs/btrfs/qgroup.c

+4 −8

Original line number	Diff line number	Diff line
		@@ -3435,24 +3435,20 @@ static int qgroup_unreserve_range(struct btrfs_inode *inode,
		{
		struct rb_node *node;
		struct rb_node *next;
		struct ulist_node *entry = NULL;
		struct ulist_node *entry;
		int ret = 0;

		node = reserved->range_changed.root.rb_node;
		if (!node)
		return 0;
		while (node) {
		entry = rb_entry(node, struct ulist_node, rb_node);
		if (entry->val < start)
		node = node->rb_right;
		else if (entry)
		node = node->rb_left;
		else
		break;
		node = node->rb_left;
		}

		/* Empty changeset */
		if (!entry)
		return 0;

		if (entry->val > start && rb_prev(&entry->rb_node))
		entry = rb_entry(rb_prev(&entry->rb_node), struct ulist_node,
		rb_node);

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