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 #include <linux/refcount.h> 23 24 #include "dm-stats.h" 25 26 /* 27 * Suspend feature flags 28 */ 29 #define DM_SUSPEND_LOCKFS_FLAG (1 << 0) 30 #define DM_SUSPEND_NOFLUSH_FLAG (1 << 1) 31 32 /* 33 * Status feature flags 34 */ 35 #define DM_STATUS_NOFLUSH_FLAG (1 << 0) 36 37 /* 38 * List of devices that a metadevice uses and should open/close. 39 */ 40 struct dm_dev_internal { 41 struct list_head list; 42 refcount_t count; 43 struct dm_dev *dm_dev; 44 }; 45 46 struct dm_table; 47 struct dm_md_mempools; 48 49 /*----------------------------------------------------------------- 50 * Internal table functions. 51 *---------------------------------------------------------------*/ 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 enum dm_queue_mode 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 void dm_table_free_md_mempools(struct dm_table *t); 74 struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t); 75 bool dm_table_supports_dax(struct dm_table *t, iterate_devices_callout_fn fn, 76 int *blocksize); 77 int device_supports_dax(struct dm_target *ti, struct dm_dev *dev, 78 sector_t start, sector_t len, void *data); 79 80 void dm_lock_md_type(struct mapped_device *md); 81 void dm_unlock_md_type(struct mapped_device *md); 82 void dm_set_md_type(struct mapped_device *md, enum dm_queue_mode type); 83 enum dm_queue_mode dm_get_md_type(struct mapped_device *md); 84 struct target_type *dm_get_immutable_target_type(struct mapped_device *md); 85 86 int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t); 87 88 /* 89 * To check the return value from dm_table_find_target(). 90 */ 91 #define dm_target_is_valid(t) ((t)->table) 92 93 /* 94 * To check whether the target type is bio-based or not (request-based). 95 */ 96 #define dm_target_bio_based(t) ((t)->type->map != NULL) 97 98 /* 99 * To check whether the target type is request-based or not (bio-based). 100 */ 101 #define dm_target_request_based(t) ((t)->type->clone_and_map_rq != NULL) 102 103 /* 104 * To check whether the target type is a hybrid (capable of being 105 * either request-based or bio-based). 106 */ 107 #define dm_target_hybrid(t) (dm_target_bio_based(t) && dm_target_request_based(t)) 108 109 /*----------------------------------------------------------------- 110 * A registry of target types. 111 *---------------------------------------------------------------*/ 112 int dm_target_init(void); 113 void dm_target_exit(void); 114 struct target_type *dm_get_target_type(const char *name); 115 void dm_put_target_type(struct target_type *tt); 116 int dm_target_iterate(void (*iter_func)(struct target_type *tt, 117 void *param), void *param); 118 119 int dm_split_args(int *argc, char ***argvp, char *input); 120 121 /* 122 * Is this mapped_device being deleted? 123 */ 124 int dm_deleting_md(struct mapped_device *md); 125 126 /* 127 * Is this mapped_device suspended? 128 */ 129 int dm_suspended_md(struct mapped_device *md); 130 131 /* 132 * Internal suspend and resume methods. 133 */ 134 int dm_suspended_internally_md(struct mapped_device *md); 135 void dm_internal_suspend_fast(struct mapped_device *md); 136 void dm_internal_resume_fast(struct mapped_device *md); 137 void dm_internal_suspend_noflush(struct mapped_device *md); 138 void dm_internal_resume(struct mapped_device *md); 139 140 /* 141 * Test if the device is scheduled for deferred remove. 142 */ 143 int dm_test_deferred_remove_flag(struct mapped_device *md); 144 145 /* 146 * Try to remove devices marked for deferred removal. 147 */ 148 void dm_deferred_remove(void); 149 150 /* 151 * The device-mapper can be driven through one of two interfaces; 152 * ioctl or filesystem, depending which patch you have applied. 153 */ 154 int dm_interface_init(void); 155 void dm_interface_exit(void); 156 157 /* 158 * sysfs interface 159 */ 160 int dm_sysfs_init(struct mapped_device *md); 161 void dm_sysfs_exit(struct mapped_device *md); 162 struct kobject *dm_kobject(struct mapped_device *md); 163 struct mapped_device *dm_get_from_kobject(struct kobject *kobj); 164 165 /* 166 * The kobject helper 167 */ 168 void dm_kobject_release(struct kobject *kobj); 169 170 /* 171 * Targets for linear and striped mappings 172 */ 173 int dm_linear_init(void); 174 void dm_linear_exit(void); 175 176 int dm_stripe_init(void); 177 void dm_stripe_exit(void); 178 179 /* 180 * mapped_device operations 181 */ 182 void dm_destroy(struct mapped_device *md); 183 void dm_destroy_immediate(struct mapped_device *md); 184 int dm_open_count(struct mapped_device *md); 185 int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred); 186 int dm_cancel_deferred_remove(struct mapped_device *md); 187 int dm_request_based(struct mapped_device *md); 188 sector_t dm_get_size(struct mapped_device *md); 189 struct request_queue *dm_get_md_queue(struct mapped_device *md); 190 int dm_get_table_device(struct mapped_device *md, dev_t dev, fmode_t mode, 191 struct dm_dev **result); 192 void dm_put_table_device(struct mapped_device *md, struct dm_dev *d); 193 struct dm_stats *dm_get_stats(struct mapped_device *md); 194 195 int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action, 196 unsigned cookie); 197 198 void dm_internal_suspend(struct mapped_device *md); 199 void dm_internal_resume(struct mapped_device *md); 200 201 int dm_io_init(void); 202 void dm_io_exit(void); 203 204 int dm_kcopyd_init(void); 205 void dm_kcopyd_exit(void); 206 207 /* 208 * Mempool operations 209 */ 210 struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, enum dm_queue_mode type, 211 unsigned integrity, unsigned per_bio_data_size, 212 unsigned min_pool_size); 213 void dm_free_md_mempools(struct dm_md_mempools *pools); 214 215 /* 216 * Various helpers 217 */ 218 unsigned dm_get_reserved_bio_based_ios(void); 219 220 #endif 221