https://github.com/torvalds/linux
Tip revision: 29594404d7fe73cd80eaa4ee8c43dcc53970c60e authored by Linus Torvalds on 11 December 2012, 03:30:57 UTC
Linux 3.7
Linux 3.7
Tip revision: 2959440
ordered-data.h
/*
* 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_ORDERED_DATA__
#define __BTRFS_ORDERED_DATA__
/* one of these per inode */
struct btrfs_ordered_inode_tree {
spinlock_t lock;
struct rb_root tree;
struct rb_node *last;
};
/*
* these are used to collect checksums done just before bios submission.
* They are attached via a list into the ordered extent, and
* checksum items are inserted into the tree after all the blocks in
* the ordered extent are on disk
*/
struct btrfs_sector_sum {
/* bytenr on disk */
u64 bytenr;
u32 sum;
};
struct btrfs_ordered_sum {
/* bytenr is the start of this extent on disk */
u64 bytenr;
/*
* this is the length in bytes covered by the sums array below.
*/
unsigned long len;
struct list_head list;
/* last field is a variable length array of btrfs_sector_sums */
struct btrfs_sector_sum sums[];
};
/*
* bits for the flags field:
*
* BTRFS_ORDERED_IO_DONE is set when all of the blocks are written.
* It is used to make sure metadata is inserted into the tree only once
* per extent.
*
* BTRFS_ORDERED_COMPLETE is set when the extent is removed from the
* rbtree, just before waking any waiters. It is used to indicate the
* IO is done and any metadata is inserted into the tree.
*/
#define BTRFS_ORDERED_IO_DONE 0 /* set when all the pages are written */
#define BTRFS_ORDERED_COMPLETE 1 /* set when removed from the tree */
#define BTRFS_ORDERED_NOCOW 2 /* set when we want to write in place */
#define BTRFS_ORDERED_COMPRESSED 3 /* writing a zlib compressed extent */
#define BTRFS_ORDERED_PREALLOC 4 /* set when writing to prealloced extent */
#define BTRFS_ORDERED_DIRECT 5 /* set when we're doing DIO with this extent */
#define BTRFS_ORDERED_IOERR 6 /* We had an io error when writing this out */
#define BTRFS_ORDERED_UPDATED_ISIZE 7 /* indicates wether this ordered extent
* has done its due diligence in updating
* the isize. */
struct btrfs_ordered_extent {
/* logical offset in the file */
u64 file_offset;
/* disk byte number */
u64 start;
/* ram length of the extent in bytes */
u64 len;
/* extent length on disk */
u64 disk_len;
/* number of bytes that still need writing */
u64 bytes_left;
/*
* the end of the ordered extent which is behind it but
* didn't update disk_i_size. Please see the comment of
* btrfs_ordered_update_i_size();
*/
u64 outstanding_isize;
/* flags (described above) */
unsigned long flags;
/* compression algorithm */
int compress_type;
/* reference count */
atomic_t refs;
/* the inode we belong to */
struct inode *inode;
/* list of checksums for insertion when the extent io is done */
struct list_head list;
/* used to wait for the BTRFS_ORDERED_COMPLETE bit */
wait_queue_head_t wait;
/* our friendly rbtree entry */
struct rb_node rb_node;
/* a per root list of all the pending ordered extents */
struct list_head root_extent_list;
struct btrfs_work work;
};
/*
* calculates the total size you need to allocate for an ordered sum
* structure spanning 'bytes' in the file
*/
static inline int btrfs_ordered_sum_size(struct btrfs_root *root,
unsigned long bytes)
{
unsigned long num_sectors = (bytes + root->sectorsize - 1) /
root->sectorsize;
num_sectors++;
return sizeof(struct btrfs_ordered_sum) +
num_sectors * sizeof(struct btrfs_sector_sum);
}
static inline void
btrfs_ordered_inode_tree_init(struct btrfs_ordered_inode_tree *t)
{
spin_lock_init(&t->lock);
t->tree = RB_ROOT;
t->last = NULL;
}
void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry);
void btrfs_remove_ordered_extent(struct inode *inode,
struct btrfs_ordered_extent *entry);
int btrfs_dec_test_ordered_pending(struct inode *inode,
struct btrfs_ordered_extent **cached,
u64 file_offset, u64 io_size, int uptodate);
int btrfs_dec_test_first_ordered_pending(struct inode *inode,
struct btrfs_ordered_extent **cached,
u64 *file_offset, u64 io_size,
int uptodate);
int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
u64 start, u64 len, u64 disk_len, int type);
int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset,
u64 start, u64 len, u64 disk_len, int type);
int btrfs_add_ordered_extent_compress(struct inode *inode, u64 file_offset,
u64 start, u64 len, u64 disk_len,
int type, int compress_type);
void btrfs_add_ordered_sum(struct inode *inode,
struct btrfs_ordered_extent *entry,
struct btrfs_ordered_sum *sum);
struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode,
u64 file_offset);
void btrfs_start_ordered_extent(struct inode *inode,
struct btrfs_ordered_extent *entry, int wait);
void btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len);
struct btrfs_ordered_extent *
btrfs_lookup_first_ordered_extent(struct inode * inode, u64 file_offset);
struct btrfs_ordered_extent *btrfs_lookup_ordered_range(struct inode *inode,
u64 file_offset,
u64 len);
int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
struct btrfs_ordered_extent *ordered);
int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr, u32 *sum);
void btrfs_run_ordered_operations(struct btrfs_root *root, int wait);
void btrfs_add_ordered_operation(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct inode *inode);
void btrfs_wait_ordered_extents(struct btrfs_root *root, int delay_iput);
int __init ordered_data_init(void);
void ordered_data_exit(void);
#endif