[deliverable/linux.git] / fs / btrfs / volumes.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_VOLUMES_
#define __BTRFS_VOLUMES_

#include <linux/bio.h>
#include <linux/sort.h>
#include "async-thread.h"
#include "ioctl.h"

#define BTRFS_STRIPE_LEN	(64 * 1024)

struct buffer_head;
struct btrfs_pending_bios {
	struct bio *head;
	struct bio *tail;
};

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;

	/* regular prio bios */
	struct btrfs_pending_bios pending_bios;
	/* WRITE_SYNC bios */
	struct btrfs_pending_bios pending_sync_bios;

	int running_pending;
	u64 generation;

	int writeable;
	int in_fs_metadata;
	int missing;
	int can_discard;

	spinlock_t io_lock;

	struct block_device *bdev;

	/* the mode sent to blkdev_get */
	fmode_t mode;

	char *name;

	/* the internal btrfs device id */
	u64 devid;

	/* size of the device */
	u64 total_bytes;

	/* size of the disk */
	u64 disk_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];

	/* per-device scrub information */
	struct scrub_dev *scrub_device;

	struct btrfs_work work;
	struct rcu_head rcu;
	struct work_struct rcu_work;

	/* readahead state */
	spinlock_t reada_lock;
	atomic_t reada_in_flight;
	u64 reada_next;
	struct reada_zone *reada_curr_zone;
	struct radix_tree_root reada_zones;
	struct radix_tree_root reada_extents;

	/* for sending down flush barriers */
	struct bio *flush_bio;
	struct completion flush_wait;
	int nobarriers;

	/* disk I/O failure stats. For detailed description refer to
	 * enum btrfs_dev_stat_values in ioctl.h */
	int dev_stats_dirty; /* counters need to be written to disk */
	atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
};

struct btrfs_fs_devices {
	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */

	/* the device with this id has the most recent copy of the super */
	u64 latest_devid;
	u64 latest_trans;
	u64 num_devices;
	u64 open_devices;
	u64 rw_devices;
	u64 missing_devices;
	u64 total_rw_bytes;
	u64 num_can_discard;
	struct block_device *latest_bdev;

	/* all of the devices in the FS, protected by a mutex
	 * so we can safely walk it to write out the supers without
	 * worrying about add/remove by the multi-device code
	 */
	struct mutex device_list_mutex;
	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 opened;

	/* set when we find or add a device that doesn't have the
	 * nonrot flag set
	 */
	int rotating;
};

struct btrfs_bio_stripe {
	struct btrfs_device *dev;
	u64 physical;
	u64 length; /* only used for discard mappings */
};

struct btrfs_bio;
typedef void (btrfs_bio_end_io_t) (struct btrfs_bio *bio, int err);

struct btrfs_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;
	int mirror_num;
	struct btrfs_bio_stripe stripes[];
};

struct btrfs_device_info {
	struct btrfs_device *dev;
	u64 dev_offset;
	u64 max_avail;
	u64 total_avail;
};

struct map_lookup {
	u64 type;
	int io_align;
	int io_width;
	int stripe_len;
	int sector_size;
	int num_stripes;
	int sub_stripes;
	struct btrfs_bio_stripe stripes[];
};

#define map_lookup_size(n) (sizeof(struct map_lookup) + \
			    (sizeof(struct btrfs_bio_stripe) * (n)))

/*
 * Restriper's general type filter
 */
#define BTRFS_BALANCE_DATA		(1ULL << 0)
#define BTRFS_BALANCE_SYSTEM		(1ULL << 1)
#define BTRFS_BALANCE_METADATA		(1ULL << 2)

#define BTRFS_BALANCE_TYPE_MASK		(BTRFS_BALANCE_DATA |	    \
					 BTRFS_BALANCE_SYSTEM |	    \
					 BTRFS_BALANCE_METADATA)

#define BTRFS_BALANCE_FORCE		(1ULL << 3)
#define BTRFS_BALANCE_RESUME		(1ULL << 4)

/*
 * Balance filters
 */
#define BTRFS_BALANCE_ARGS_PROFILES	(1ULL << 0)
#define BTRFS_BALANCE_ARGS_USAGE	(1ULL << 1)
#define BTRFS_BALANCE_ARGS_DEVID	(1ULL << 2)
#define BTRFS_BALANCE_ARGS_DRANGE	(1ULL << 3)
#define BTRFS_BALANCE_ARGS_VRANGE	(1ULL << 4)

/*
 * Profile changing flags.  When SOFT is set we won't relocate chunk if
 * it already has the target profile (even though it may be
 * half-filled).
 */
#define BTRFS_BALANCE_ARGS_CONVERT	(1ULL << 8)
#define BTRFS_BALANCE_ARGS_SOFT		(1ULL << 9)

struct btrfs_balance_args;
struct btrfs_balance_progress;
struct btrfs_balance_control {
	struct btrfs_fs_info *fs_info;

	struct btrfs_balance_args data;
	struct btrfs_balance_args meta;
	struct btrfs_balance_args sys;

	u64 flags;

	struct btrfs_balance_progress stat;
};

int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
				   u64 end, u64 *length);

#define btrfs_bio_size(n) (sizeof(struct btrfs_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_bio **bbio_ret, int mirror_num);
int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
		     u64 chunk_start, u64 physical, u64 devid,
		     u64 **logical, int *naddrs, int *stripe_len);
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_open_devices(struct btrfs_fs_devices *fs_devices,
		       fmode_t flags, void *holder);
int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
			  struct btrfs_fs_devices **fs_devices_ret);
int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
void 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);
void btrfs_cleanup_fs_uuids(void);
int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len);
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_balance_control *bctl,
		  struct btrfs_ioctl_balance_args *bargs);
int btrfs_recover_balance(struct btrfs_root *tree_root);
int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
			 u64 *start, u64 *max_avail);
struct btrfs_device *btrfs_find_device_for_logical(struct btrfs_root *root,
						   u64 logical, int mirror_num);
void btrfs_dev_stat_print_on_error(struct btrfs_device *device);
void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);

static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
				      int index)
{
	atomic_inc(dev->dev_stat_values + index);
	dev->dev_stats_dirty = 1;
}

static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
				      int index)
{
	return atomic_read(dev->dev_stat_values + index);
}

static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
						int index)
{
	int ret;

	ret = atomic_xchg(dev->dev_stat_values + index, 0);
	dev->dev_stats_dirty = 1;
	return ret;
}

static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
				      int index, unsigned long val)
{
	atomic_set(dev->dev_stat_values + index, val);
	dev->dev_stats_dirty = 1;
}

static inline void btrfs_dev_stat_reset(struct btrfs_device *dev,
					int index)
{
	btrfs_dev_stat_set(dev, index, 0);
}
#endif
Commit	Line	Data
0b86a832 CM	1	/*
	2	* Copyright (C) 2007 Oracle. All rights reserved.
	3	*
	4	* This program is free software; you can redistribute it and/or
	5	* modify it under the terms of the GNU General Public
	6	* License v2 as published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope that it will be useful,
	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	11	* General Public License for more details.
	12	*
	13	* You should have received a copy of the GNU General Public
	14	* License along with this program; if not, write to the
	15	* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
	16	* Boston, MA 021110-1307, USA.
	17	*/
	18
	19	#ifndef __BTRFS_VOLUMES_
	20	#define __BTRFS_VOLUMES_
8790d502	21
cea9e445	22	#include <linux/bio.h>
b2117a39	23	#include <linux/sort.h>
8b712842	24	#include "async-thread.h"
442a4f63	25	#include "ioctl.h"
cea9e445	26
b2117a39 MX	27	#define BTRFS_STRIPE_LEN (64 * 1024)
b2117a39 MX	28
f2984462	29	struct buffer_head;
ffbd517d CM	30	struct btrfs_pending_bios {
	31	struct bio *head;
	32	struct bio *tail;
	33	};
	34
0b86a832 CM	35	struct btrfs_device {
0b86a832 CM	36	struct list_head dev_list;
b3075717	37	struct list_head dev_alloc_list;
2b82032c	38	struct btrfs_fs_devices *fs_devices;
0b86a832	39	struct btrfs_root *dev_root;
ffbd517d CM	40
	41	/* regular prio bios */
	42	struct btrfs_pending_bios pending_bios;
	43	/* WRITE_SYNC bios */
	44	struct btrfs_pending_bios pending_sync_bios;
	45
8b712842	46	int running_pending;
dfe25020	47	u64 generation;
b3075717	48
2b82032c	49	int writeable;
dfe25020	50	int in_fs_metadata;
cd02dca5	51	int missing;
d5e2003c	52	int can_discard;
b3075717	53
8790d502	54	spinlock_t io_lock;
0b86a832 CM	55
	56	struct block_device *bdev;
	57
d4d77629	58	/* the mode sent to blkdev_get */
15916de8 CM	59	fmode_t mode;
15916de8 CM	60
8a4b83cc CM	61	char *name;
8a4b83cc CM	62
0b86a832 CM	63	/* the internal btrfs device id */
	64	u64 devid;
	65
	66	/* size of the device */
	67	u64 total_bytes;
	68
d6397bae CB	69	/* size of the disk */
	70	u64 disk_total_bytes;
	71
0b86a832 CM	72	/* bytes used */
	73	u64 bytes_used;
	74
	75	/* optimal io alignment for this device */
	76	u32 io_align;
	77
	78	/* optimal io width for this device */
	79	u32 io_width;
	80
	81	/* minimal io size for this device */
	82	u32 sector_size;
	83
0b86a832 CM	84	/* type and info about this device */
	85	u64 type;
	86
0b86a832	87	/* physical drive uuid (or lvm uuid) */
e17cade2	88	u8 uuid[BTRFS_UUID_SIZE];
8b712842	89
a2de733c AJ	90	/* per-device scrub information */
	91	struct scrub_dev *scrub_device;
	92
8b712842	93	struct btrfs_work work;
1f78160c XG	94	struct rcu_head rcu;
1f78160c XG	95	struct work_struct rcu_work;
90519d66 AJ	96
	97	/* readahead state */
	98	spinlock_t reada_lock;
	99	atomic_t reada_in_flight;
	100	u64 reada_next;
	101	struct reada_zone *reada_curr_zone;
	102	struct radix_tree_root reada_zones;
	103	struct radix_tree_root reada_extents;
387125fc CM	104
	105	/* for sending down flush barriers */
	106	struct bio *flush_bio;
	107	struct completion flush_wait;
	108	int nobarriers;
	109
442a4f63 SB	110	/* disk I/O failure stats. For detailed description refer to
	111	* enum btrfs_dev_stat_values in ioctl.h */
	112	int dev_stats_dirty; /* counters need to be written to disk */
	113	atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
0b86a832 CM	114	};
0b86a832 CM	115
8a4b83cc CM	116	struct btrfs_fs_devices {
	117	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
	118
d4a78947	119	/* the device with this id has the most recent copy of the super */
8a4b83cc CM	120	u64 latest_devid;
8a4b83cc CM	121	u64 latest_trans;
8a4b83cc	122	u64 num_devices;
a0af469b	123	u64 open_devices;
2b82032c	124	u64 rw_devices;
cd02dca5	125	u64 missing_devices;
2b82032c	126	u64 total_rw_bytes;
d5e2003c	127	u64 num_can_discard;
8a4b83cc	128	struct block_device *latest_bdev;
e5e9a520 CM	129
	130	/* all of the devices in the FS, protected by a mutex
	131	* so we can safely walk it to write out the supers without
	132	* worrying about add/remove by the multi-device code
	133	*/
	134	struct mutex device_list_mutex;
8a4b83cc	135	struct list_head devices;
b3075717 CM	136
	137	/* devices not currently being allocated */
	138	struct list_head alloc_list;
8a4b83cc	139	struct list_head list;
2b82032c YZ	140
	141	struct btrfs_fs_devices *seed;
	142	int seeding;
2b82032c YZ	143
2b82032c YZ	144	int opened;
c289811c CM	145
	146	/* set when we find or add a device that doesn't have the
	147	* nonrot flag set
	148	*/
	149	int rotating;
8a4b83cc CM	150	};
8a4b83cc CM	151
cea9e445 CM	152	struct btrfs_bio_stripe {
	153	struct btrfs_device *dev;
	154	u64 physical;
fce3bb9a	155	u64 length; /* only used for discard mappings */
cea9e445 CM	156	};
cea9e445 CM	157
a1d3c478 JS	158	struct btrfs_bio;
	159	typedef void (btrfs_bio_end_io_t) (struct btrfs_bio *bio, int err);
	160
	161	struct btrfs_bio {
cea9e445 CM	162	atomic_t stripes_pending;
cea9e445 CM	163	bio_end_io_t *end_io;
7d2b4daa	164	struct bio *orig_bio;
cea9e445	165	void *private;
a236aed1 CM	166	atomic_t error;
a236aed1 CM	167	int max_errors;
cea9e445	168	int num_stripes;
a1d3c478	169	int mirror_num;
cea9e445 CM	170	struct btrfs_bio_stripe stripes[];
	171	};
	172
b2117a39 MX	173	struct btrfs_device_info {
	174	struct btrfs_device *dev;
	175	u64 dev_offset;
	176	u64 max_avail;
73c5de00	177	u64 total_avail;
b2117a39 MX	178	};
b2117a39 MX	179
1abe9b8a	180	struct map_lookup {
	181	u64 type;
	182	int io_align;
	183	int io_width;
	184	int stripe_len;
	185	int sector_size;
	186	int num_stripes;
	187	int sub_stripes;
	188	struct btrfs_bio_stripe stripes[];
	189	};
	190
a2de733c AJ	191	#define map_lookup_size(n) (sizeof(struct map_lookup) + \
	192	(sizeof(struct btrfs_bio_stripe) * (n)))
	193
f43ffb60 ID	194	/*
	195	* Restriper's general type filter
	196	*/
	197	#define BTRFS_BALANCE_DATA (1ULL << 0)
	198	#define BTRFS_BALANCE_SYSTEM (1ULL << 1)
	199	#define BTRFS_BALANCE_METADATA (1ULL << 2)
	200
	201	#define BTRFS_BALANCE_TYPE_MASK (BTRFS_BALANCE_DATA \| \
	202	BTRFS_BALANCE_SYSTEM \| \
	203	BTRFS_BALANCE_METADATA)
e4d8ec0f ID	204
e4d8ec0f ID	205	#define BTRFS_BALANCE_FORCE (1ULL << 3)
59641015	206	#define BTRFS_BALANCE_RESUME (1ULL << 4)
e4d8ec0f	207
ed25e9b2 ID	208	/*
	209	* Balance filters
	210	*/
	211	#define BTRFS_BALANCE_ARGS_PROFILES (1ULL << 0)
5ce5b3c0	212	#define BTRFS_BALANCE_ARGS_USAGE (1ULL << 1)
409d404b	213	#define BTRFS_BALANCE_ARGS_DEVID (1ULL << 2)
94e60d5a	214	#define BTRFS_BALANCE_ARGS_DRANGE (1ULL << 3)
ea67176a	215	#define BTRFS_BALANCE_ARGS_VRANGE (1ULL << 4)
f43ffb60	216
cfa4c961 ID	217	/*
	218	* Profile changing flags. When SOFT is set we won't relocate chunk if
	219	* it already has the target profile (even though it may be
	220	* half-filled).
	221	*/
e4d8ec0f	222	#define BTRFS_BALANCE_ARGS_CONVERT (1ULL << 8)
cfa4c961	223	#define BTRFS_BALANCE_ARGS_SOFT (1ULL << 9)
e4d8ec0f	224
c9e9f97b	225	struct btrfs_balance_args;
19a39dce	226	struct btrfs_balance_progress;
c9e9f97b ID	227	struct btrfs_balance_control {
	228	struct btrfs_fs_info *fs_info;
	229
	230	struct btrfs_balance_args data;
	231	struct btrfs_balance_args meta;
	232	struct btrfs_balance_args sys;
	233
	234	u64 flags;
19a39dce ID	235
19a39dce ID	236	struct btrfs_balance_progress stat;
c9e9f97b ID	237	};
c9e9f97b ID	238
6d07bcec MX	239	int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
	240	u64 end, u64 *length);
	241
a1d3c478	242	#define btrfs_bio_size(n) (sizeof(struct btrfs_bio) + \
cea9e445 CM	243	(sizeof(struct btrfs_bio_stripe) * (n)))
cea9e445 CM	244
0b86a832 CM	245	int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
0b86a832 CM	246	struct btrfs_device *device,
e17cade2	247	u64 chunk_tree, u64 chunk_objectid,
2b82032c	248	u64 chunk_offset, u64 start, u64 num_bytes);
cea9e445 CM	249	int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
cea9e445 CM	250	u64 logical, u64 *length,
a1d3c478	251	struct btrfs_bio **bbio_ret, int mirror_num);
a512bbf8 YZ	252	int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
	253	u64 chunk_start, u64 physical, u64 devid,
	254	u64 *logical, int naddrs, int *stripe_len);
e4404d6e	255	int btrfs_read_sys_array(struct btrfs_root *root);
0b86a832 CM	256	int btrfs_read_chunk_tree(struct btrfs_root *root);
0b86a832 CM	257	int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
2b82032c	258	struct btrfs_root *extent_root, u64 type);
0b86a832 CM	259	void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
0b86a832 CM	260	void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
f188591e	261	int btrfs_map_bio(struct btrfs_root root, int rw, struct bio bio,
8b712842	262	int mirror_num, int async_submit);
8a4b83cc	263	int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
97288f2c CH	264	fmode_t flags, void *holder);
97288f2c CH	265	int btrfs_scan_one_device(const char path, fmode_t flags, void holder,
8a4b83cc CM	266	struct btrfs_fs_devices **fs_devices_ret);
8a4b83cc CM	267	int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
143bede5	268	void btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices);
8a4b83cc CM	269	int btrfs_add_device(struct btrfs_trans_handle *trans,
	270	struct btrfs_root *root,
	271	struct btrfs_device *device);
a061fc8d	272	int btrfs_rm_device(struct btrfs_root root, char device_path);
143bede5	273	void btrfs_cleanup_fs_uuids(void);
f188591e	274	int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len);
8f18cf13 CM	275	int btrfs_grow_device(struct btrfs_trans_handle *trans,
	276	struct btrfs_device *device, u64 new_size);
	277	struct btrfs_device btrfs_find_device(struct btrfs_root root, u64 devid,
2b82032c	278	u8 uuid, u8 fsid);
8f18cf13	279	int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
788f20eb	280	int btrfs_init_new_device(struct btrfs_root root, char path);
c9e9f97b ID	281	int btrfs_balance(struct btrfs_balance_control *bctl,
c9e9f97b ID	282	struct btrfs_ioctl_balance_args *bargs);
59641015	283	int btrfs_recover_balance(struct btrfs_root *tree_root);
837d5b6e	284	int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
a7e99c69	285	int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
2b82032c	286	int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
125ccb0a	287	int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
ba1bf481	288	u64 start, u64 max_avail);
442a4f63 SB	289	struct btrfs_device btrfs_find_device_for_logical(struct btrfs_root root,
	290	u64 logical, int mirror_num);
	291	void btrfs_dev_stat_print_on_error(struct btrfs_device *device);
	292	void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
	293
	294	static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
	295	int index)
	296	{
	297	atomic_inc(dev->dev_stat_values + index);
	298	dev->dev_stats_dirty = 1;
	299	}
	300
	301	static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
	302	int index)
	303	{
	304	return atomic_read(dev->dev_stat_values + index);
	305	}
	306
	307	static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
	308	int index)
	309	{
	310	int ret;
	311
	312	ret = atomic_xchg(dev->dev_stat_values + index, 0);
	313	dev->dev_stats_dirty = 1;
	314	return ret;
	315	}
	316
	317	static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
	318	int index, unsigned long val)
	319	{
	320	atomic_set(dev->dev_stat_values + index, val);
	321	dev->dev_stats_dirty = 1;
	322	}
	323
	324	static inline void btrfs_dev_stat_reset(struct btrfs_device *dev,
	325	int index)
	326	{
	327	btrfs_dev_stat_set(dev, index, 0);
	328	}
0b86a832	329	#endif