1 /* 2 * Internal header file for device mapper 3 * 4 * Copyright (C) 2001, 2002 Sistina Software 5 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. 6 * 7 * This file is released under the LGPL. 8 */ 9 10 #ifndef DM_INTERNAL_H 11 #define DM_INTERNAL_H 12 13 #include <linux/fs.h> 14 #include <linux/device-mapper.h> 15 #include <linux/list.h> 16 #include <linux/moduleparam.h> 17 #include <linux/blkdev.h> 18 #include <linux/backing-dev.h> 19 #include <linux/hdreg.h> 20 #include <linux/completion.h> 21 #include <linux/kobject.h> 22 23 #include "dm-stats.h" 24 25 /* 26 * Suspend feature flags 27 */ 28 #define DM_SUSPEND_LOCKFS_FLAG (1 << 0) 29 #define DM_SUSPEND_NOFLUSH_FLAG (1 << 1) 30 31 /* 32 * Status feature flags 33 */ 34 #define DM_STATUS_NOFLUSH_FLAG (1 << 0) 35 36 /* 37 * List of devices that a metadevice uses and should open/close. 38 */ 39 struct dm_dev_internal { 40 struct list_head list; 41 atomic_t count; 42 struct dm_dev *dm_dev; 43 }; 44 45 struct dm_table; 46 struct dm_md_mempools; 47 48 /*----------------------------------------------------------------- 49 * Internal table functions. 50 *---------------------------------------------------------------*/ 51 void dm_table_destroy(struct dm_table *t); 52 void dm_table_event_callback(struct dm_table *t, 53 void (*fn)(void *), void *context); 54 struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index); 55 struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector); 56 bool dm_table_has_no_data_devices(struct dm_table *table); 57 int dm_calculate_queue_limits(struct dm_table *table, 58 struct queue_limits *limits); 59 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, 60 struct queue_limits *limits); 61 struct list_head *dm_table_get_devices(struct dm_table *t); 62 void dm_table_presuspend_targets(struct dm_table *t); 63 void dm_table_presuspend_undo_targets(struct dm_table *t); 64 void dm_table_postsuspend_targets(struct dm_table *t); 65 int dm_table_resume_targets(struct dm_table *t); 66 int dm_table_any_congested(struct dm_table *t, int bdi_bits); 67 unsigned dm_table_get_type(struct dm_table *t); 68 struct target_type *dm_table_get_immutable_target_type(struct dm_table *t); 69 struct dm_target *dm_table_get_immutable_target(struct dm_table *t); 70 struct dm_target *dm_table_get_wildcard_target(struct dm_table *t); 71 bool dm_table_bio_based(struct dm_table *t); 72 bool dm_table_request_based(struct dm_table *t); 73 bool dm_table_all_blk_mq_devices(struct dm_table *t); 74 void dm_table_free_md_mempools(struct dm_table *t); 75 struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t); 76 77 void dm_lock_md_type(struct mapped_device *md); 78 void dm_unlock_md_type(struct mapped_device *md); 79 void dm_set_md_type(struct mapped_device *md, unsigned type); 80 unsigned dm_get_md_type(struct mapped_device *md); 81 struct target_type *dm_get_immutable_target_type(struct mapped_device *md); 82 83 int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t); 84 85 /* 86 * To check the return value from dm_table_find_target(). 87 */ 88 #define dm_target_is_valid(t) ((t)->table) 89 90 /* 91 * To check whether the target type is bio-based or not (request-based). 92 */ 93 #define dm_target_bio_based(t) ((t)->type->map != NULL) 94 95 /* 96 * To check whether the target type is request-based or not (bio-based). 97 */ 98 #define dm_target_request_based(t) ((t)->type->clone_and_map_rq != NULL) 99 100 /* 101 * To check whether the target type is a hybrid (capable of being 102 * either request-based or bio-based). 103 */ 104 #define dm_target_hybrid(t) (dm_target_bio_based(t) && dm_target_request_based(t)) 105 106 /*----------------------------------------------------------------- 107 * A registry of target types. 108 *---------------------------------------------------------------*/ 109 int dm_target_init(void); 110 void dm_target_exit(void); 111 struct target_type *dm_get_target_type(const char *name); 112 void dm_put_target_type(struct target_type *tt); 113 int dm_target_iterate(void (*iter_func)(struct target_type *tt, 114 void *param), void *param); 115 116 int dm_split_args(int *argc, char ***argvp, char *input); 117 118 /* 119 * Is this mapped_device being deleted? 120 */ 121 int dm_deleting_md(struct mapped_device *md); 122 123 /* 124 * Is this mapped_device suspended? 125 */ 126 int dm_suspended_md(struct mapped_device *md); 127 128 /* 129 * Internal suspend and resume methods. 130 */ 131 int dm_suspended_internally_md(struct mapped_device *md); 132 void dm_internal_suspend_fast(struct mapped_device *md); 133 void dm_internal_resume_fast(struct mapped_device *md); 134 void dm_internal_suspend_noflush(struct mapped_device *md); 135 void dm_internal_resume(struct mapped_device *md); 136 137 /* 138 * Test if the device is scheduled for deferred remove. 139 */ 140 int dm_test_deferred_remove_flag(struct mapped_device *md); 141 142 /* 143 * Try to remove devices marked for deferred removal. 144 */ 145 void dm_deferred_remove(void); 146 147 /* 148 * The device-mapper can be driven through one of two interfaces; 149 * ioctl or filesystem, depending which patch you have applied. 150 */ 151 int dm_interface_init(void); 152 void dm_interface_exit(void); 153 154 /* 155 * sysfs interface 156 */ 157 int dm_sysfs_init(struct mapped_device *md); 158 void dm_sysfs_exit(struct mapped_device *md); 159 struct kobject *dm_kobject(struct mapped_device *md); 160 struct mapped_device *dm_get_from_kobject(struct kobject *kobj); 161 162 /* 163 * The kobject helper 164 */ 165 void dm_kobject_release(struct kobject *kobj); 166 167 /* 168 * Targets for linear and striped mappings 169 */ 170 int dm_linear_init(void); 171 void dm_linear_exit(void); 172 173 int dm_stripe_init(void); 174 void dm_stripe_exit(void); 175 176 /* 177 * mapped_device operations 178 */ 179 void dm_destroy(struct mapped_device *md); 180 void dm_destroy_immediate(struct mapped_device *md); 181 int dm_open_count(struct mapped_device *md); 182 int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred); 183 int dm_cancel_deferred_remove(struct mapped_device *md); 184 int dm_request_based(struct mapped_device *md); 185 sector_t dm_get_size(struct mapped_device *md); 186 struct request_queue *dm_get_md_queue(struct mapped_device *md); 187 int dm_get_table_device(struct mapped_device *md, dev_t dev, fmode_t mode, 188 struct dm_dev **result); 189 void dm_put_table_device(struct mapped_device *md, struct dm_dev *d); 190 struct dm_stats *dm_get_stats(struct mapped_device *md); 191 192 int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action, 193 unsigned cookie); 194 195 void dm_internal_suspend(struct mapped_device *md); 196 void dm_internal_resume(struct mapped_device *md); 197 198 int dm_io_init(void); 199 void dm_io_exit(void); 200 201 int dm_kcopyd_init(void); 202 void dm_kcopyd_exit(void); 203 204 /* 205 * Mempool operations 206 */ 207 struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, unsigned type, 208 unsigned integrity, unsigned per_bio_data_size); 209 void dm_free_md_mempools(struct dm_md_mempools *pools); 210 211 /* 212 * Various helpers 213 */ 214 unsigned dm_get_reserved_bio_based_ios(void); 215 216 #endif 217