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>
23 * Suspend feature flags
25 #define DM_SUSPEND_LOCKFS_FLAG (1 << 0)
26 #define DM_SUSPEND_NOFLUSH_FLAG (1 << 1)
29 * Status feature flags
31 #define DM_STATUS_NOFLUSH_FLAG (1 << 0)
34 * Type of table and mapped_device's mempool
36 #define DM_TYPE_NONE 0
37 #define DM_TYPE_BIO_BASED 1
38 #define DM_TYPE_REQUEST_BASED 2
41 * List of devices that a metadevice uses and should open/close.
43 struct dm_dev_internal {
44 struct list_head list;
50 struct dm_md_mempools;
52 /*-----------------------------------------------------------------
53 * Internal table functions.
54 *---------------------------------------------------------------*/
55 void dm_table_destroy(struct dm_table *t);
56 void dm_table_event_callback(struct dm_table *t,
57 void (*fn)(void *), void *context);
58 struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index);
59 struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector);
60 bool dm_table_has_no_data_devices(struct dm_table *table);
61 int dm_calculate_queue_limits(struct dm_table *table,
62 struct queue_limits *limits);
63 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
64 struct queue_limits *limits);
65 struct list_head *dm_table_get_devices(struct dm_table *t);
66 void dm_table_presuspend_targets(struct dm_table *t);
67 void dm_table_postsuspend_targets(struct dm_table *t);
68 int dm_table_resume_targets(struct dm_table *t);
69 int dm_table_any_congested(struct dm_table *t, int bdi_bits);
70 int dm_table_any_busy_target(struct dm_table *t);
71 unsigned dm_table_get_type(struct dm_table *t);
72 struct target_type *dm_table_get_immutable_target_type(struct dm_table *t);
73 bool dm_table_request_based(struct dm_table *t);
74 bool dm_table_supports_discards(struct dm_table *t);
75 int dm_table_alloc_md_mempools(struct dm_table *t);
76 void dm_table_free_md_mempools(struct dm_table *t);
77 struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t);
79 int dm_queue_merge_is_compulsory(struct request_queue *q);
81 void dm_lock_md_type(struct mapped_device *md);
82 void dm_unlock_md_type(struct mapped_device *md);
83 void dm_set_md_type(struct mapped_device *md, unsigned type);
84 unsigned dm_get_md_type(struct mapped_device *md);
85 struct target_type *dm_get_immutable_target_type(struct mapped_device *md);
87 int dm_setup_md_queue(struct mapped_device *md);
90 * To check the return value from dm_table_find_target().
92 #define dm_target_is_valid(t) ((t)->table)
95 * To check whether the target type is bio-based or not (request-based).
97 #define dm_target_bio_based(t) ((t)->type->map != NULL)
100 * To check whether the target type is request-based or not (bio-based).
102 #define dm_target_request_based(t) ((t)->type->map_rq != NULL)
105 * To check whether the target type is a hybrid (capable of being
106 * either request-based or bio-based).
108 #define dm_target_hybrid(t) (dm_target_bio_based(t) && dm_target_request_based(t))
110 /*-----------------------------------------------------------------
111 * A registry of target types.
112 *---------------------------------------------------------------*/
113 int dm_target_init(void);
114 void dm_target_exit(void);
115 struct target_type *dm_get_target_type(const char *name);
116 void dm_put_target_type(struct target_type *tt);
117 int dm_target_iterate(void (*iter_func)(struct target_type *tt,
118 void *param), void *param);
120 int dm_split_args(int *argc, char ***argvp, char *input);
123 * Is this mapped_device being deleted?
125 int dm_deleting_md(struct mapped_device *md);
128 * Is this mapped_device suspended?
130 int dm_suspended_md(struct mapped_device *md);
133 * Test if the device is scheduled for deferred remove.
135 int dm_test_deferred_remove_flag(struct mapped_device *md);
138 * Try to remove devices marked for deferred removal.
140 void dm_deferred_remove(void);
143 * The device-mapper can be driven through one of two interfaces;
144 * ioctl or filesystem, depending which patch you have applied.
146 int dm_interface_init(void);
147 void dm_interface_exit(void);
152 int dm_sysfs_init(struct mapped_device *md);
153 void dm_sysfs_exit(struct mapped_device *md);
154 struct kobject *dm_kobject(struct mapped_device *md);
155 struct mapped_device *dm_get_from_kobject(struct kobject *kobj);
156 struct completion *dm_get_completion_from_kobject(struct kobject *kobj);
159 * Targets for linear and striped mappings
161 int dm_linear_init(void);
162 void dm_linear_exit(void);
164 int dm_stripe_init(void);
165 void dm_stripe_exit(void);
168 * mapped_device operations
170 void dm_destroy(struct mapped_device *md);
171 void dm_destroy_immediate(struct mapped_device *md);
172 int dm_open_count(struct mapped_device *md);
173 int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred);
174 int dm_cancel_deferred_remove(struct mapped_device *md);
175 int dm_request_based(struct mapped_device *md);
176 sector_t dm_get_size(struct mapped_device *md);
177 struct dm_stats *dm_get_stats(struct mapped_device *md);
179 int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
182 void dm_internal_suspend(struct mapped_device *md);
183 void dm_internal_resume(struct mapped_device *md);
185 int dm_io_init(void);
186 void dm_io_exit(void);
188 int dm_kcopyd_init(void);
189 void dm_kcopyd_exit(void);
194 struct dm_md_mempools *dm_alloc_md_mempools(unsigned type, unsigned integrity, unsigned per_bio_data_size);
195 void dm_free_md_mempools(struct dm_md_mempools *pools);
198 * Helpers that are used by DM core
200 unsigned dm_get_reserved_bio_based_ios(void);
201 unsigned dm_get_reserved_rq_based_ios(void);
203 static inline bool dm_message_test_buffer_overflow(char *result, unsigned maxlen)
205 return !maxlen || strlen(result) + 1 >= maxlen;