linux/fs/btrfs/volumes.h
Chris Mason b30757178d Btrfs: Add a special device list for chunk allocations
This allows other code that needs to walk every device in the FS to do so
without locking against allocations.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25 11:04:02 -04:00

132 lines
3.7 KiB
C

/*
* 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_VOLUMES_
#define __BTRFS_VOLUMES_
#include <linux/bio.h>
struct buffer_head;
struct btrfs_device {
struct list_head dev_list;
struct list_head dev_alloc_list;
struct btrfs_root *dev_root;
struct buffer_head *pending_io;
int barriers;
spinlock_t io_lock;
struct block_device *bdev;
u64 total_ios;
char *name;
/* the internal btrfs device id */
u64 devid;
/* size of the device */
u64 total_bytes;
/* bytes used */
u64 bytes_used;
/* optimal io alignment for this device */
u32 io_align;
/* optimal io width for this device */
u32 io_width;
/* minimal io size for this device */
u32 sector_size;
/* type and info about this device */
u64 type;
/* physical drive uuid (or lvm uuid) */
u8 uuid[BTRFS_UUID_SIZE];
};
struct btrfs_fs_devices {
u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
/* the device with this id has the most recent coyp of the super */
u64 latest_devid;
u64 latest_trans;
u64 lowest_devid;
u64 num_devices;
struct block_device *latest_bdev;
struct block_device *lowest_bdev;
/* all of the devices in the FS */
struct list_head devices;
/* devices not currently being allocated */
struct list_head alloc_list;
struct list_head list;
};
struct btrfs_bio_stripe {
struct btrfs_device *dev;
u64 physical;
};
struct btrfs_multi_bio {
atomic_t stripes_pending;
bio_end_io_t *end_io;
void *private;
int error;
int num_stripes;
struct btrfs_bio_stripe stripes[];
};
#define btrfs_multi_bio_size(n) (sizeof(struct btrfs_multi_bio) + \
(sizeof(struct btrfs_bio_stripe) * (n)))
int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
struct btrfs_device *device,
u64 chunk_tree, u64 chunk_objectid,
u64 chunk_offset,
u64 num_bytes, u64 *start);
int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
u64 logical, u64 *length,
struct btrfs_multi_bio **multi_ret, int mirror_num);
int btrfs_read_sys_array(struct btrfs_root *root);
int btrfs_read_chunk_tree(struct btrfs_root *root);
int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
struct btrfs_root *extent_root, u64 *start,
u64 *num_bytes, u64 type);
void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
int mirror_num);
int btrfs_read_super_device(struct btrfs_root *root, struct extent_buffer *buf);
int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
int flags, void *holder);
int btrfs_scan_one_device(const char *path, int flags, void *holder,
struct btrfs_fs_devices **fs_devices_ret);
int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
int btrfs_add_device(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_device *device);
int btrfs_cleanup_fs_uuids(void);
int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len);
int btrfs_unplug_page(struct btrfs_mapping_tree *map_tree,
u64 logical, struct page *page);
#endif