drivers/md/dm.h

   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/blkdev.h>
  17 #include <linux/hdreg.h>
  18
  19 /*
  20  * Suspend feature flags
  21  */
  22 #define DM_SUSPEND_LOCKFS_FLAG          (1 << 0)
  23 #define DM_SUSPEND_NOFLUSH_FLAG         (1 << 1)
  24
  25 /*
  26  * List of devices that a metadevice uses and should open/close.
  27  */
  28 struct dm_dev {
  29         struct list_head list;
  30
  31         atomic_t count;
  32         int mode;
  33         struct block_device *bdev;
  34         char name[16];
  35 };
  36
  37 struct dm_table;
  38
  39 /*-----------------------------------------------------------------
  40  * Internal table functions.
  41  *---------------------------------------------------------------*/
  42 void dm_table_event_callback(struct dm_table *t,
  43                              void (*fn)(void *), void *context);
  44 struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index);
  45 struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector);
  46 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q);
  47 struct list_head *dm_table_get_devices(struct dm_table *t);
  48 void dm_table_presuspend_targets(struct dm_table *t);
  49 void dm_table_postsuspend_targets(struct dm_table *t);
  50 int dm_table_resume_targets(struct dm_table *t);
  51 int dm_table_any_congested(struct dm_table *t, int bdi_bits);
  52 void dm_table_unplug_all(struct dm_table *t);
  53
  54 /*
  55  * To check the return value from dm_table_find_target().
  56  */
  57 #define dm_target_is_valid(t) ((t)->table)
  58
  59 /*-----------------------------------------------------------------
  60  * A registry of target types.
  61  *---------------------------------------------------------------*/
  62 int dm_target_init(void);
  63 void dm_target_exit(void);
  64 struct target_type *dm_get_target_type(const char *name);
  65 void dm_put_target_type(struct target_type *t);
  66 int dm_target_iterate(void (*iter_func)(struct target_type *tt,
  67                                         void *param), void *param);
  68
  69 /*-----------------------------------------------------------------
  70  * Useful inlines.
  71  *---------------------------------------------------------------*/
  72 static inline int array_too_big(unsigned long fixed, unsigned long obj,
  73                                 unsigned long num)
  74 {
  75         return (num > (ULONG_MAX - fixed) / obj);
  76 }
  77
  78 int dm_split_args(int *argc, char ***argvp, char *input);
  79
  80 /*
  81  * The device-mapper can be driven through one of two interfaces;
  82  * ioctl or filesystem, depending which patch you have applied.
  83  */
  84 int dm_interface_init(void);
  85 void dm_interface_exit(void);
  86
  87 /*
  88  * Targets for linear and striped mappings
  89  */
  90 int dm_linear_init(void);
  91 void dm_linear_exit(void);
  92
  93 int dm_stripe_init(void);
  94 void dm_stripe_exit(void);
  95
  96 void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size);
  97 union map_info *dm_get_mapinfo(struct bio *bio);
  98 int dm_open_count(struct mapped_device *md);
  99 int dm_lock_for_deletion(struct mapped_device *md);
 100
 101 void dm_kobject_uevent(struct mapped_device *md);
 102
 103 int dm_kcopyd_init(void);
 104 void dm_kcopyd_exit(void);
 105
 106 #endif