extent_io.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 #ifndef __BTRFS_EXTENT_IO_H__
  20 #define __BTRFS_EXTENT_IO_H__
  21
  22 #if BTRFS_FLAT_INCLUDES
  23 #include "kerncompat.h"
  24 #include "extent-cache.h"
  25 #include "list.h"
  26 #else
  27 #include <btrfs/kerncompat.h>
  28 #include <btrfs/extent-cache.h>
  29 #include <btrfs/list.h>
  30 #endif /* BTRFS_FLAT_INCLUDES */
  31
  32 #define EXTENT_DIRTY 1
  33 #define EXTENT_WRITEBACK (1 << 1)
  34 #define EXTENT_UPTODATE (1 << 2)
  35 #define EXTENT_LOCKED (1 << 3)
  36 #define EXTENT_NEW (1 << 4)
  37 #define EXTENT_DELALLOC (1 << 5)
  38 #define EXTENT_DEFRAG (1 << 6)
  39 #define EXTENT_DEFRAG_DONE (1 << 7)
  40 #define EXTENT_BUFFER_FILLED (1 << 8)
  41 #define EXTENT_CSUM (1 << 9)
  42 #define EXTENT_BAD_TRANSID (1 << 10)
  43 #define EXTENT_BUFFER_DUMMY (1 << 11)
  44 #define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK)
  45
  46 #define BLOCK_GROUP_DATA     EXTENT_WRITEBACK
  47 #define BLOCK_GROUP_METADATA EXTENT_UPTODATE
  48 #define BLOCK_GROUP_SYSTEM   EXTENT_NEW
  49
  50 #define BLOCK_GROUP_DIRTY EXTENT_DIRTY
  51
  52 struct btrfs_fs_info;
  53
  54 struct extent_io_tree {
  55         struct cache_tree state;
  56         struct cache_tree cache;
  57         struct list_head lru;
  58         u64 cache_size;
  59 };
  60
  61 struct extent_state {
  62         struct cache_extent cache_node;
  63         u64 start;
  64         u64 end;
  65         int refs;
  66         unsigned long state;
  67         u64 xprivate;
  68 };
  69
  70 struct extent_buffer {
  71         struct cache_extent cache_node;
  72         u64 start;
  73         u64 dev_bytenr;
  74         u32 len;
  75         struct extent_io_tree *tree;
  76         struct list_head lru;
  77         struct list_head recow;
  78         int refs;
  79         int flags;
  80         int fd;
  81         char data[];
  82 };
  83
  84 static inline void extent_buffer_get(struct extent_buffer *eb)
  85 {
  86         eb->refs++;
  87 }
  88
  89 void extent_io_tree_init(struct extent_io_tree *tree);
  90 void extent_io_tree_cleanup(struct extent_io_tree *tree);
  91 int set_extent_bits(struct extent_io_tree *tree, u64 start,
  92                     u64 end, int bits, gfp_t mask);
  93 int clear_extent_bits(struct extent_io_tree *tree, u64 start,
  94                       u64 end, int bits, gfp_t mask);
  95 int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
  96                           u64 *start_ret, u64 *end_ret, int bits);
  97 int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
  98                    int bits, int filled);
  99 int set_extent_dirty(struct extent_io_tree *tree, u64 start,
 100                      u64 end, gfp_t mask);
 101 int clear_extent_dirty(struct extent_io_tree *tree, u64 start,
 102                        u64 end, gfp_t mask);
 103 static inline int set_extent_buffer_uptodate(struct extent_buffer *eb)
 104 {
 105         eb->flags |= EXTENT_UPTODATE;
 106         return 0;
 107 }
 108
 109 static inline int clear_extent_buffer_uptodate(struct extent_io_tree *tree,
 110                                 struct extent_buffer *eb)
 111 {
 112         eb->flags &= ~EXTENT_UPTODATE;
 113         return 0;
 114 }
 115
 116 static inline int extent_buffer_uptodate(struct extent_buffer *eb)
 117 {
 118         if (!eb || IS_ERR(eb))
 119                 return 0;
 120         if (eb->flags & EXTENT_UPTODATE)
 121                 return 1;
 122         return 0;
 123 }
 124
 125 int set_state_private(struct extent_io_tree *tree, u64 start, u64 xprivate);
 126 int get_state_private(struct extent_io_tree *tree, u64 start, u64 *xprivate);
 127 struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree,
 128                                          u64 bytenr, u32 blocksize);
 129 struct extent_buffer *find_first_extent_buffer(struct extent_io_tree *tree,
 130                                                u64 start);
 131 struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
 132                                           u64 bytenr, u32 blocksize);
 133 struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
 134 void free_extent_buffer(struct extent_buffer *eb);
 135 int read_extent_from_disk(struct extent_buffer *eb,
 136                           unsigned long offset, unsigned long len);
 137 int write_extent_to_disk(struct extent_buffer *eb);
 138 int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
 139                          unsigned long start, unsigned long len);
 140 void read_extent_buffer(struct extent_buffer *eb, void *dst,
 141                         unsigned long start, unsigned long len);
 142 void write_extent_buffer(struct extent_buffer *eb, const void *src,
 143                          unsigned long start, unsigned long len);
 144 void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
 145                         unsigned long dst_offset, unsigned long src_offset,
 146                         unsigned long len);
 147 void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
 148                            unsigned long src_offset, unsigned long len);
 149 void memset_extent_buffer(struct extent_buffer *eb, char c,
 150                           unsigned long start, unsigned long len);
 151 int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start,
 152                            unsigned long nr);
 153 int set_extent_buffer_dirty(struct extent_buffer *eb);
 154 int clear_extent_buffer_dirty(struct extent_buffer *eb);
 155 int read_data_from_disk(struct btrfs_fs_info *info, void *buf, u64 offset,
 156                         u64 bytes, int mirror);
 157 int write_data_to_disk(struct btrfs_fs_info *info, void *buf, u64 offset,
 158                        u64 bytes, int mirror);
 159 #endif