2 * Internal header file for device mapper
4 * Copyright (C) 2001, 2002 Sistina Software
6 * This file is released under the LGPL.
13 #include <linux/device-mapper.h>
14 #include <linux/list.h>
15 #include <linux/blkdev.h>
17 #define DM_NAME "device-mapper"
18 #define DMWARN(f, x...) printk(KERN_WARNING DM_NAME ": " f "\n" , ## x)
19 #define DMERR(f, x...) printk(KERN_ERR DM_NAME ": " f "\n" , ## x)
20 #define DMINFO(f, x...) printk(KERN_INFO DM_NAME ": " f "\n" , ## x)
23 * FIXME: I think this should be with the definition of sector_t
27 #define SECTOR_FORMAT "%Lu"
29 #define SECTOR_FORMAT "%lu"
32 #define SECTOR_SHIFT 9
35 * List of devices that a metadevice uses and should open/close.
38 struct list_head list;
42 struct block_device *bdev;
48 /*-----------------------------------------------------------------
49 * Functions for manipulating a struct mapped_device.
50 * Drop the reference with dm_put when you finish with the object.
51 *---------------------------------------------------------------*/
52 int dm_create(struct mapped_device **md);
53 int dm_create_with_minor(unsigned int minor, struct mapped_device **md);
56 * Reference counting for md.
58 void dm_get(struct mapped_device *md);
59 void dm_put(struct mapped_device *md);
62 * A device can still be used while suspended, but I/O is deferred.
64 int dm_suspend(struct mapped_device *md);
65 int dm_resume(struct mapped_device *md);
68 * The device must be suspended before calling this method.
70 int dm_swap_table(struct mapped_device *md, struct dm_table *t);
73 * Drop a reference on the table when you've finished with the
76 struct dm_table *dm_get_table(struct mapped_device *md);
81 uint32_t dm_get_event_nr(struct mapped_device *md);
82 int dm_wait_event(struct mapped_device *md, int event_nr);
87 struct gendisk *dm_disk(struct mapped_device *md);
88 int dm_suspended(struct mapped_device *md);
90 /*-----------------------------------------------------------------
91 * Functions for manipulating a table. Tables are also reference
93 *---------------------------------------------------------------*/
94 int dm_table_create(struct dm_table **result, int mode, unsigned num_targets);
96 void dm_table_get(struct dm_table *t);
97 void dm_table_put(struct dm_table *t);
99 int dm_table_add_target(struct dm_table *t, const char *type,
100 sector_t start, sector_t len, char *params);
101 int dm_table_complete(struct dm_table *t);
102 void dm_table_event_callback(struct dm_table *t,
103 void (*fn)(void *), void *context);
104 void dm_table_event(struct dm_table *t);
105 sector_t dm_table_get_size(struct dm_table *t);
106 struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index);
107 struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector);
108 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q);
109 unsigned int dm_table_get_num_targets(struct dm_table *t);
110 struct list_head *dm_table_get_devices(struct dm_table *t);
111 int dm_table_get_mode(struct dm_table *t);
112 void dm_table_suspend_targets(struct dm_table *t);
113 void dm_table_resume_targets(struct dm_table *t);
114 int dm_table_any_congested(struct dm_table *t, int bdi_bits);
115 void dm_table_unplug_all(struct dm_table *t);
117 /*-----------------------------------------------------------------
118 * A registry of target types.
119 *---------------------------------------------------------------*/
120 int dm_target_init(void);
121 void dm_target_exit(void);
122 struct target_type *dm_get_target_type(const char *name);
123 void dm_put_target_type(struct target_type *t);
124 int dm_target_iterate(void (*iter_func)(struct target_type *tt,
125 void *param), void *param);
128 /*-----------------------------------------------------------------
130 *---------------------------------------------------------------*/
131 static inline int array_too_big(unsigned long fixed, unsigned long obj,
134 return (num > (ULONG_MAX - fixed) / obj);
138 * ceiling(n / size) * size
140 static inline unsigned long dm_round_up(unsigned long n, unsigned long size)
142 unsigned long r = n % size;
143 return n + (r ? (size - r) : 0);
149 static inline unsigned long dm_div_up(unsigned long n, unsigned long size)
151 return dm_round_up(n, size) / size;
154 static inline sector_t to_sector(unsigned long n)
159 static inline unsigned long to_bytes(sector_t n)
165 * The device-mapper can be driven through one of two interfaces;
166 * ioctl or filesystem, depending which patch you have applied.
168 int dm_interface_init(void);
169 void dm_interface_exit(void);
172 * Targets for linear and striped mappings
174 int dm_linear_init(void);
175 void dm_linear_exit(void);
177 int dm_stripe_init(void);
178 void dm_stripe_exit(void);
180 void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size);