]>
git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blob - drivers/md/dm.h
2 * Internal header file for device mapper
4 * Copyright (C) 2001, 2002 Sistina Software
5 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
7 * This file is released under the LGPL.
14 #include <linux/device-mapper.h>
15 #include <linux/list.h>
16 #include <linux/blkdev.h>
17 #include <linux/hdreg.h>
18 #include <linux/completion.h>
19 #include <linux/kobject.h>
24 * Suspend feature flags
26 #define DM_SUSPEND_LOCKFS_FLAG (1 << 0)
27 #define DM_SUSPEND_NOFLUSH_FLAG (1 << 1)
30 * Status feature flags
32 #define DM_STATUS_NOFLUSH_FLAG (1 << 0)
35 * Type of table and mapped_device's mempool
37 #define DM_TYPE_NONE 0
38 #define DM_TYPE_BIO_BASED 1
39 #define DM_TYPE_REQUEST_BASED 2
42 * List of devices that a metadevice uses and should open/close.
44 struct dm_dev_internal
{
45 struct list_head list
;
51 struct dm_md_mempools
;
53 /*-----------------------------------------------------------------
54 * Internal table functions.
55 *---------------------------------------------------------------*/
56 void dm_table_destroy(struct dm_table
*t
);
57 void dm_table_event_callback(struct dm_table
*t
,
58 void (*fn
)(void *), void *context
);
59 struct dm_target
*dm_table_get_target(struct dm_table
*t
, unsigned int index
);
60 struct dm_target
*dm_table_find_target(struct dm_table
*t
, sector_t sector
);
61 bool dm_table_has_no_data_devices(struct dm_table
*table
);
62 int dm_calculate_queue_limits(struct dm_table
*table
,
63 struct queue_limits
*limits
);
64 void dm_table_set_restrictions(struct dm_table
*t
, struct request_queue
*q
,
65 struct queue_limits
*limits
);
66 struct list_head
*dm_table_get_devices(struct dm_table
*t
);
67 void dm_table_presuspend_targets(struct dm_table
*t
);
68 void dm_table_postsuspend_targets(struct dm_table
*t
);
69 int dm_table_resume_targets(struct dm_table
*t
);
70 int dm_table_any_congested(struct dm_table
*t
, int bdi_bits
);
71 int dm_table_any_busy_target(struct dm_table
*t
);
72 unsigned dm_table_get_type(struct dm_table
*t
);
73 struct target_type
*dm_table_get_immutable_target_type(struct dm_table
*t
);
74 bool dm_table_request_based(struct dm_table
*t
);
75 bool dm_table_supports_discards(struct dm_table
*t
);
76 int dm_table_alloc_md_mempools(struct dm_table
*t
);
77 void dm_table_free_md_mempools(struct dm_table
*t
);
78 struct dm_md_mempools
*dm_table_get_md_mempools(struct dm_table
*t
);
80 int dm_queue_merge_is_compulsory(struct request_queue
*q
);
82 void dm_lock_md_type(struct mapped_device
*md
);
83 void dm_unlock_md_type(struct mapped_device
*md
);
84 void dm_set_md_type(struct mapped_device
*md
, unsigned type
);
85 unsigned dm_get_md_type(struct mapped_device
*md
);
86 struct target_type
*dm_get_immutable_target_type(struct mapped_device
*md
);
88 int dm_setup_md_queue(struct mapped_device
*md
);
91 * To check the return value from dm_table_find_target().
93 #define dm_target_is_valid(t) ((t)->table)
96 * To check whether the target type is bio-based or not (request-based).
98 #define dm_target_bio_based(t) ((t)->type->map != NULL)
101 * To check whether the target type is request-based or not (bio-based).
103 #define dm_target_request_based(t) ((t)->type->map_rq != NULL)
106 * To check whether the target type is a hybrid (capable of being
107 * either request-based or bio-based).
109 #define dm_target_hybrid(t) (dm_target_bio_based(t) && dm_target_request_based(t))
111 /*-----------------------------------------------------------------
112 * A registry of target types.
113 *---------------------------------------------------------------*/
114 int dm_target_init(void);
115 void dm_target_exit(void);
116 struct target_type
*dm_get_target_type(const char *name
);
117 void dm_put_target_type(struct target_type
*tt
);
118 int dm_target_iterate(void (*iter_func
)(struct target_type
*tt
,
119 void *param
), void *param
);
121 int dm_split_args(int *argc
, char ***argvp
, char *input
);
124 * Is this mapped_device being deleted?
126 int dm_deleting_md(struct mapped_device
*md
);
129 * Is this mapped_device suspended?
131 int dm_suspended_md(struct mapped_device
*md
);
134 * Test if the device is scheduled for deferred remove.
136 int dm_test_deferred_remove_flag(struct mapped_device
*md
);
139 * Try to remove devices marked for deferred removal.
141 void dm_deferred_remove(void);
144 * The device-mapper can be driven through one of two interfaces;
145 * ioctl or filesystem, depending which patch you have applied.
147 int dm_interface_init(void);
148 void dm_interface_exit(void);
153 struct dm_kobject_holder
{
155 struct completion completion
;
158 static inline struct completion
*dm_get_completion_from_kobject(struct kobject
*kobj
)
160 return &container_of(kobj
, struct dm_kobject_holder
, kobj
)->completion
;
163 int dm_sysfs_init(struct mapped_device
*md
);
164 void dm_sysfs_exit(struct mapped_device
*md
);
165 struct kobject
*dm_kobject(struct mapped_device
*md
);
166 struct mapped_device
*dm_get_from_kobject(struct kobject
*kobj
);
171 void dm_kobject_release(struct kobject
*kobj
);
174 * Targets for linear and striped mappings
176 int dm_linear_init(void);
177 void dm_linear_exit(void);
179 int dm_stripe_init(void);
180 void dm_stripe_exit(void);
183 * mapped_device operations
185 void dm_destroy(struct mapped_device
*md
);
186 void dm_destroy_immediate(struct mapped_device
*md
);
187 int dm_open_count(struct mapped_device
*md
);
188 int dm_lock_for_deletion(struct mapped_device
*md
, bool mark_deferred
, bool only_deferred
);
189 int dm_cancel_deferred_remove(struct mapped_device
*md
);
190 int dm_request_based(struct mapped_device
*md
);
191 sector_t
dm_get_size(struct mapped_device
*md
);
192 struct dm_stats
*dm_get_stats(struct mapped_device
*md
);
194 int dm_kobject_uevent(struct mapped_device
*md
, enum kobject_action action
,
197 void dm_internal_suspend(struct mapped_device
*md
);
198 void dm_internal_resume(struct mapped_device
*md
);
200 int dm_io_init(void);
201 void dm_io_exit(void);
203 int dm_kcopyd_init(void);
204 void dm_kcopyd_exit(void);
209 struct dm_md_mempools
*dm_alloc_md_mempools(unsigned type
, unsigned integrity
, unsigned per_bio_data_size
);
210 void dm_free_md_mempools(struct dm_md_mempools
*pools
);
213 * Helpers that are used by DM core
215 unsigned dm_get_reserved_bio_based_ios(void);
216 unsigned dm_get_reserved_rq_based_ios(void);
218 static inline bool dm_message_test_buffer_overflow(char *result
, unsigned maxlen
)
220 return !maxlen
|| strlen(result
) + 1 >= maxlen
;