/* * Copyright (C) 2011 STRATO AG * written by Arne Jansen <sensille@gmx.net> * Distributed under the GNU GPL license version 2. * */ #ifndef __ULIST__ #define __ULIST__ #include <linux/list.h> #include <linux/rbtree.h> /* * ulist is a generic data structure to hold a collection of unique u64 * values. The only operations it supports is adding to the list and * enumerating it. * It is possible to store an auxiliary value along with the key. * */ struct ulist_iterator { #ifdef CONFIG_BTRFS_DEBUG int i; #endif struct list_head *cur_list; /* hint to start search */ }; /* * element of the list */ struct ulist_node { u64 val; /* value to store */ u64 aux; /* auxiliary value saved along with the val */ #ifdef CONFIG_BTRFS_DEBUG int seqnum; /* sequence number this node is added */ #endif struct list_head list; /* used to link node */ struct rb_node rb_node; /* used to speed up search */ }; struct ulist { /* * number of elements stored in list */ unsigned long nnodes; struct list_head nodes; struct rb_root root; }; void ulist_init(struct ulist *ulist); void ulist_reinit(struct ulist *ulist); struct ulist *ulist_alloc(gfp_t gfp_mask); void ulist_free(struct ulist *ulist); int ulist_add(struct ulist *ulist, u64 val, u64 aux, gfp_t gfp_mask); int ulist_add_merge(struct ulist *ulist, u64 val, u64 aux, u64 *old_aux, gfp_t gfp_mask); struct ulist_node *ulist_next(struct ulist *ulist, struct ulist_iterator *uiter); #define ULIST_ITER_INIT(uiter) ((uiter)->cur_list = NULL) #endif