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 #define DM_NAME "device-mapper" 20 21 #define DMERR(f, arg...) printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg) 22 #define DMWARN(f, arg...) printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg) 23 #define DMINFO(f, arg...) printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg) 24 25 #define DMEMIT(x...) sz += ((sz >= maxlen) ? \ 26 0 : scnprintf(result + sz, maxlen - sz, x)) 27 28 #define SECTOR_SHIFT 9 29 30 /* 31 * List of devices that a metadevice uses and should open/close. 32 */ 33 struct dm_dev { 34 struct list_head list; 35 36 atomic_t count; 37 int mode; 38 struct block_device *bdev; 39 char name[16]; 40 }; 41 42 struct dm_table; 43 44 /*----------------------------------------------------------------- 45 * Internal table functions. 46 *---------------------------------------------------------------*/ 47 void dm_table_event_callback(struct dm_table *t, 48 void (*fn)(void *), void *context); 49 struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index); 50 struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector); 51 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q); 52 struct list_head *dm_table_get_devices(struct dm_table *t); 53 void dm_table_presuspend_targets(struct dm_table *t); 54 void dm_table_postsuspend_targets(struct dm_table *t); 55 void dm_table_resume_targets(struct dm_table *t); 56 int dm_table_any_congested(struct dm_table *t, int bdi_bits); 57 void dm_table_unplug_all(struct dm_table *t); 58 int dm_table_flush_all(struct dm_table *t); 59 60 /*----------------------------------------------------------------- 61 * A registry of target types. 62 *---------------------------------------------------------------*/ 63 int dm_target_init(void); 64 void dm_target_exit(void); 65 struct target_type *dm_get_target_type(const char *name); 66 void dm_put_target_type(struct target_type *t); 67 int dm_target_iterate(void (*iter_func)(struct target_type *tt, 68 void *param), void *param); 69 70 /*----------------------------------------------------------------- 71 * Useful inlines. 72 *---------------------------------------------------------------*/ 73 static inline int array_too_big(unsigned long fixed, unsigned long obj, 74 unsigned long num) 75 { 76 return (num > (ULONG_MAX - fixed) / obj); 77 } 78 79 /* 80 * Ceiling(n / sz) 81 */ 82 #define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz)) 83 84 #define dm_sector_div_up(n, sz) ( \ 85 { \ 86 sector_t _r = ((n) + (sz) - 1); \ 87 sector_div(_r, (sz)); \ 88 _r; \ 89 } \ 90 ) 91 92 /* 93 * ceiling(n / size) * size 94 */ 95 #define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz)) 96 97 static inline sector_t to_sector(unsigned long n) 98 { 99 return (n >> 9); 100 } 101 102 static inline unsigned long to_bytes(sector_t n) 103 { 104 return (n << 9); 105 } 106 107 int dm_split_args(int *argc, char ***argvp, char *input); 108 109 /* 110 * The device-mapper can be driven through one of two interfaces; 111 * ioctl or filesystem, depending which patch you have applied. 112 */ 113 int dm_interface_init(void); 114 void dm_interface_exit(void); 115 116 /* 117 * Targets for linear and striped mappings 118 */ 119 int dm_linear_init(void); 120 void dm_linear_exit(void); 121 122 int dm_stripe_init(void); 123 void dm_stripe_exit(void); 124 125 void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size); 126 union map_info *dm_get_mapinfo(struct bio *bio); 127 int dm_open_count(struct mapped_device *md); 128 int dm_lock_for_deletion(struct mapped_device *md); 129 130 #endif 131