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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__
#include "kerncompat.h"
#include "kernel-lib/bitops.h"
#include "kernel-lib/list.h"
#include "common/extent-cache.h"
#define EXTENT_BUFFER_UPTODATE (1U << 0)
#define EXTENT_BUFFER_DIRTY (1U << 1)
#define EXTENT_BUFFER_BAD_TRANSID (1U << 2)
#define EXTENT_BUFFER_DUMMY (1U << 3)
#define BLOCK_GROUP_DATA (1U << 1)
#define BLOCK_GROUP_METADATA (1U << 2)
#define BLOCK_GROUP_SYSTEM (1U << 4)
/*
* 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 ((1U << 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 btrfs_trans_handle;
struct extent_buffer {
struct cache_extent cache_node;
u64 start;
struct list_head lru;
struct list_head recow;
u32 len;
int refs;
u32 flags;
struct btrfs_fs_info *fs_info;
char data[] __attribute__((aligned(8)));
};
static inline void extent_buffer_get(struct extent_buffer *eb)
{
eb->refs++;
}
static inline int set_extent_buffer_uptodate(struct extent_buffer *eb)
{
eb->flags |= EXTENT_BUFFER_UPTODATE;
return 0;
}
static inline int clear_extent_buffer_uptodate(struct extent_buffer *eb)
{
eb->flags &= ~EXTENT_BUFFER_UPTODATE;
return 0;
}
static inline int extent_buffer_uptodate(struct extent_buffer *eb)
{
if (!eb || IS_ERR(eb))
return 0;
if (eb->flags & EXTENT_BUFFER_UPTODATE)
return 1;
return 0;
}
struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
u64 bytenr);
struct extent_buffer *find_first_extent_buffer(struct btrfs_fs_info *fs_info,
u64 start);
struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
u64 bytenr, u32 blocksize);
struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
u64 bytenr, u32 blocksize);
void free_extent_buffer(struct extent_buffer *eb);
void free_extent_buffer_nocache(struct extent_buffer *eb);
void free_extent_buffer_stale(struct extent_buffer *eb);
int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv,
unsigned long start, unsigned long len);
void read_extent_buffer(const struct extent_buffer *eb, void *dst,
unsigned long start, unsigned long len);
void write_extent_buffer_fsid(struct extent_buffer *eb, const void *src);
void write_extent_buffer_chunk_tree_uuid(struct extent_buffer *eb,
const void *src);
void write_extent_buffer(struct extent_buffer *eb, const void *src,
unsigned long start, unsigned long len);
void copy_extent_buffer_full(struct extent_buffer *dst,
const struct extent_buffer *src);
void copy_extent_buffer(struct extent_buffer *dst,
const struct extent_buffer *src,
unsigned long dst_offset, unsigned long src_offset,
unsigned long len);
void memcpy_extent_buffer(struct extent_buffer *dst,
unsigned long dst_offset, unsigned long src_offset,
unsigned long len);
void memmove_extent_buffer(struct extent_buffer *dst,
const 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(const struct extent_buffer *eb, unsigned long start,
unsigned long nr);
int set_extent_buffer_dirty(struct extent_buffer *eb);
int btrfs_clear_buffer_dirty(struct btrfs_trans_handle *trans,
struct extent_buffer *eb);
int read_data_from_disk(struct btrfs_fs_info *info, void *buf, u64 logical,
u64 *len, int mirror);
int write_data_to_disk(struct btrfs_fs_info *info, const void *buf, u64 offset,
u64 bytes);
void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start,
unsigned long pos, unsigned long len);
void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start,
unsigned long pos, unsigned long len);
void extent_buffer_init_cache(struct btrfs_fs_info *fs_info);
void extent_buffer_free_cache(struct btrfs_fs_info *fs_info);
void btrfs_readahead_node_child(struct extent_buffer *node, int slot);
#endif
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