2b82032c34
Seed device is a special btrfs with SEEDING super flag set and can only be mounted in read-only mode. Seed devices allow people to create new btrfs on top of it. The new FS contains the same contents as the seed device, but it can be mounted in read-write mode. This patch does the following: 1) split code in btrfs_alloc_chunk into two parts. The first part does makes the newly allocated chunk usable, but does not do any operation that modifies the chunk tree. The second part does the the chunk tree modifications. This division is for the bootstrap step of adding storage to the seed device. 2) Update device management code to handle seed device. The basic idea is: For an FS grown from seed devices, its seed devices are put into a list. Seed devices are opened on demand at mounting time. If any seed device is missing or has been changed, btrfs kernel module will refuse to mount the FS. 3) make btrfs_find_block_group not return NULL when all block groups are read-only. Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
159 lines
4.6 KiB
C
159 lines
4.6 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>
|
|
#include "async-thread.h"
|
|
|
|
struct buffer_head;
|
|
struct btrfs_device {
|
|
struct list_head dev_list;
|
|
struct list_head dev_alloc_list;
|
|
struct btrfs_fs_devices *fs_devices;
|
|
struct btrfs_root *dev_root;
|
|
struct buffer_head *pending_io;
|
|
struct bio *pending_bios;
|
|
struct bio *pending_bio_tail;
|
|
int running_pending;
|
|
u64 generation;
|
|
|
|
int barriers;
|
|
int writeable;
|
|
int in_fs_metadata;
|
|
|
|
spinlock_t io_lock;
|
|
|
|
struct block_device *bdev;
|
|
|
|
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_work work;
|
|
};
|
|
|
|
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 num_devices;
|
|
u64 open_devices;
|
|
u64 rw_devices;
|
|
u64 total_rw_bytes;
|
|
struct block_device *latest_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_fs_devices *seed;
|
|
int seeding;
|
|
int sprouted;
|
|
|
|
int opened;
|
|
};
|
|
|
|
struct btrfs_bio_stripe {
|
|
struct btrfs_device *dev;
|
|
u64 physical;
|
|
};
|
|
|
|
struct btrfs_multi_bio {
|
|
atomic_t stripes_pending;
|
|
bio_end_io_t *end_io;
|
|
struct bio *orig_bio;
|
|
void *private;
|
|
atomic_t error;
|
|
int max_errors;
|
|
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 start, u64 num_bytes);
|
|
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 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 async_submit);
|
|
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_close_extra_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_rm_device(struct btrfs_root *root, char *device_path);
|
|
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);
|
|
int btrfs_grow_device(struct btrfs_trans_handle *trans,
|
|
struct btrfs_device *device, u64 new_size);
|
|
struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
|
|
u8 *uuid, u8 *fsid);
|
|
int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
|
|
int btrfs_init_new_device(struct btrfs_root *root, char *path);
|
|
int btrfs_balance(struct btrfs_root *dev_root);
|
|
void btrfs_unlock_volumes(void);
|
|
void btrfs_lock_volumes(void);
|
|
int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
|
|
#endif
|