include/linux/radix-tree.h

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