radix-tree.h

   1 /*
   2  * Copyright (C) 2007 Oracle.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19 /*
  20  * Copyright (C) 2001 Momchil Velikov
  21  * Portions Copyright (C) 2001 Christoph Hellwig
  22  *
  23  * This program is free software; you can redistribute it and/or
  24  * modify it under the terms of the GNU General Public License as
  25  * published by the Free Software Foundation; either version 2, or (at
  26  * your option) any later version.
  27  *
  28  * This program is distributed in the hope that it will be useful, but
  29  * WITHOUT ANY WARRANTY; without even the implied warranty of
  30  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  31  * General Public License for more details.
  32  *
  33  * You should have received a copy of the GNU General Public License
  34  * along with this program; if not, write to the Free Software
  35  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  36  */
  37 #ifndef _LINUX_RADIX_TREE_H
  38 #define _LINUX_RADIX_TREE_H
  39
  40 #include "kerncompat.h"
  41
  42 #define RADIX_TREE_MAX_TAGS 2
  43
  44 /* root tags are stored in gfp_mask, shifted by __GFP_BITS_SHIFT */
  45 struct radix_tree_root {
  46         unsigned int            height;
  47         gfp_t                   gfp_mask;
  48         struct radix_tree_node  *rnode;
  49 };
  50
  51 #define RADIX_TREE_INIT(mask)   {                                       \
  52         .height = 0,                                                    \
  53         .gfp_mask = (mask),                                             \
  54         .rnode = NULL,                                                  \
  55 }
  56
  57 #define RADIX_TREE(name, mask) \
  58         struct radix_tree_root name = RADIX_TREE_INIT(mask)
  59
  60 #define INIT_RADIX_TREE(root, mask)                                     \
  61 do {                                                                    \
  62         (root)->height = 0;                                             \
  63         (root)->gfp_mask = (mask);                                      \
  64         (root)->rnode = NULL;                                           \
  65 } while (0)
  66
  67 int radix_tree_insert(struct radix_tree_root *, unsigned long, void *);
  68 void *radix_tree_lookup(struct radix_tree_root *, unsigned long);
  69 void **radix_tree_lookup_slot(struct radix_tree_root *, unsigned long);
  70 void *radix_tree_delete(struct radix_tree_root *, unsigned long);
  71 unsigned int
  72 radix_tree_gang_lookup(struct radix_tree_root *root, void **results,
  73                         unsigned long first_index, unsigned int max_items);
  74 int radix_tree_preload(gfp_t gfp_mask);
  75 void radix_tree_init(void);
  76 void *radix_tree_tag_set(struct radix_tree_root *root,
  77                         unsigned long index, unsigned int tag);
  78 void *radix_tree_tag_clear(struct radix_tree_root *root,
  79                         unsigned long index, unsigned int tag);
  80 int radix_tree_tag_get(struct radix_tree_root *root,
  81                         unsigned long index, unsigned int tag);
  82 unsigned int
  83 radix_tree_gang_lookup_tag(struct radix_tree_root *root, void **results,
  84                 unsigned long first_index, unsigned int max_items,
  85                 unsigned int tag);
  86 int radix_tree_tagged(struct radix_tree_root *root, unsigned int tag);
  87
  88 static inline void radix_tree_preload_end(void)
  89 {
  90         preempt_enable();
  91 }
  92
  93 #endif /* _LINUX_RADIX_TREE_H */