btrfs-progs/extent_io.h

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/*
* Copyright (C) 2007 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#ifndef __BTRFS_EXTENT_IO_H__
#define __BTRFS_EXTENT_IO_H__
#if BTRFS_FLAT_INCLUDES
#include "kerncompat.h"
#include "extent-cache.h"
#include "list.h"
#else
#include <btrfs/kerncompat.h>
#include <btrfs/extent-cache.h>
#include <btrfs/list.h>
#endif /* BTRFS_FLAT_INCLUDES */
#define EXTENT_DIRTY 1
#define EXTENT_WRITEBACK (1 << 1)
#define EXTENT_UPTODATE (1 << 2)
#define EXTENT_LOCKED (1 << 3)
#define EXTENT_NEW (1 << 4)
#define EXTENT_DELALLOC (1 << 5)
#define EXTENT_DEFRAG (1 << 6)
#define EXTENT_DEFRAG_DONE (1 << 7)
#define EXTENT_BUFFER_FILLED (1 << 8)
#define EXTENT_CSUM (1 << 9)
#define EXTENT_BAD_TRANSID (1 << 10)
#define EXTENT_BUFFER_DUMMY (1 << 11)
#define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK)
#define BLOCK_GROUP_DATA EXTENT_WRITEBACK
#define BLOCK_GROUP_METADATA EXTENT_UPTODATE
#define BLOCK_GROUP_SYSTEM EXTENT_NEW
#define BLOCK_GROUP_DIRTY EXTENT_DIRTY
/*
* The extent buffer bitmap operations are done with byte granularity instead of
* word granularity for two reasons:
* 1. The bitmaps must be little-endian on disk.
* 2. Bitmap items are not guaranteed to be aligned to a word and therefore a
* single word in a bitmap may straddle two pages in the extent buffer.
*/
#define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE)
#define BYTE_MASK ((1 << BITS_PER_BYTE) - 1)
#define BITMAP_FIRST_BYTE_MASK(start) \
((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK)
#define BITMAP_LAST_BYTE_MASK(nbits) \
(BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1)))
static inline int le_test_bit(int nr, const u8 *addr)
{
return 1U & (addr[BIT_BYTE(nr)] >> (nr & (BITS_PER_BYTE-1)));
}
struct btrfs_fs_info;
struct extent_io_tree {
struct cache_tree state;
struct cache_tree cache;
struct list_head lru;
u64 cache_size;
};
struct extent_state {
struct cache_extent cache_node;
u64 start;
u64 end;
int refs;
unsigned long state;
u64 xprivate;
};
struct extent_buffer {
struct cache_extent cache_node;
u64 start;
u64 dev_bytenr;
u32 len;
struct extent_io_tree *tree;
struct list_head lru;
struct list_head recow;
int refs;
int flags;
int fd;
char data[];
};
static inline void extent_buffer_get(struct extent_buffer *eb)
{
eb->refs++;
}
void extent_io_tree_init(struct extent_io_tree *tree);
void extent_io_tree_cleanup(struct extent_io_tree *tree);
int set_extent_bits(struct extent_io_tree *tree, u64 start,
u64 end, int bits, gfp_t mask);
int clear_extent_bits(struct extent_io_tree *tree, u64 start,
u64 end, int bits, gfp_t mask);
int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
u64 *start_ret, u64 *end_ret, int bits);
int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
int bits, int filled);
int set_extent_dirty(struct extent_io_tree *tree, u64 start,
u64 end, gfp_t mask);
int clear_extent_dirty(struct extent_io_tree *tree, u64 start,
u64 end, gfp_t mask);
static inline int set_extent_buffer_uptodate(struct extent_buffer *eb)
{
eb->flags |= EXTENT_UPTODATE;
return 0;
}
static inline int clear_extent_buffer_uptodate(struct extent_io_tree *tree,
struct extent_buffer *eb)
{
eb->flags &= ~EXTENT_UPTODATE;
return 0;
}
static inline int extent_buffer_uptodate(struct extent_buffer *eb)
{
if (!eb || IS_ERR(eb))
return 0;
if (eb->flags & EXTENT_UPTODATE)
return 1;
return 0;
}
int set_state_private(struct extent_io_tree *tree, u64 start, u64 xprivate);
int get_state_private(struct extent_io_tree *tree, u64 start, u64 *xprivate);
struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree,
u64 bytenr, u32 blocksize);
struct extent_buffer *find_first_extent_buffer(struct extent_io_tree *tree,
u64 start);
struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
u64 bytenr, u32 blocksize);
struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
void free_extent_buffer(struct extent_buffer *eb);
int read_extent_from_disk(struct extent_buffer *eb,
unsigned long offset, unsigned long len);
int write_extent_to_disk(struct extent_buffer *eb);
int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
unsigned long start, unsigned long len);
void read_extent_buffer(struct extent_buffer *eb, void *dst,
unsigned long start, unsigned long len);
void write_extent_buffer(struct extent_buffer *eb, const void *src,
unsigned long start, unsigned long len);
void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
unsigned long dst_offset, unsigned long src_offset,
unsigned long len);
void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
unsigned long src_offset, unsigned long len);
void memset_extent_buffer(struct extent_buffer *eb, char c,
unsigned long start, unsigned long len);
int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start,
unsigned long nr);
int set_extent_buffer_dirty(struct extent_buffer *eb);
int clear_extent_buffer_dirty(struct extent_buffer *eb);
int read_data_from_disk(struct btrfs_fs_info *info, void *buf, u64 offset,
u64 bytes, int mirror);
int write_data_to_disk(struct btrfs_fs_info *info, void *buf, u64 offset,
u64 bytes, int mirror);
#endif