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 #ifdef CONFIG_DM_DEBUG 25 # define DMDEBUG(f, arg...) printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX " DEBUG: " f "\n", ## arg) 26 #else 27 # define DMDEBUG(f, arg...) do {} while (0) 28 #endif 29 30 #define DMEMIT(x...) sz += ((sz >= maxlen) ? \ 31 0 : scnprintf(result + sz, maxlen - sz, x)) 32 33 #define SECTOR_SHIFT 9 34 35 /* 36 * List of devices that a metadevice uses and should open/close. 37 */ 38 struct dm_dev { 39 struct list_head list; 40 41 atomic_t count; 42 int mode; 43 struct block_device *bdev; 44 char name[16]; 45 }; 46 47 struct dm_table; 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 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q); 57 struct list_head *dm_table_get_devices(struct dm_table *t); 58 void dm_table_presuspend_targets(struct dm_table *t); 59 void dm_table_postsuspend_targets(struct dm_table *t); 60 void dm_table_resume_targets(struct dm_table *t); 61 int dm_table_any_congested(struct dm_table *t, int bdi_bits); 62 void dm_table_unplug_all(struct dm_table *t); 63 int dm_table_flush_all(struct dm_table *t); 64 65 /*----------------------------------------------------------------- 66 * A registry of target types. 67 *---------------------------------------------------------------*/ 68 int dm_target_init(void); 69 void dm_target_exit(void); 70 struct target_type *dm_get_target_type(const char *name); 71 void dm_put_target_type(struct target_type *t); 72 int dm_target_iterate(void (*iter_func)(struct target_type *tt, 73 void *param), void *param); 74 75 /*----------------------------------------------------------------- 76 * Useful inlines. 77 *---------------------------------------------------------------*/ 78 static inline int array_too_big(unsigned long fixed, unsigned long obj, 79 unsigned long num) 80 { 81 return (num > (ULONG_MAX - fixed) / obj); 82 } 83 84 /* 85 * Ceiling(n / sz) 86 */ 87 #define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz)) 88 89 #define dm_sector_div_up(n, sz) ( \ 90 { \ 91 sector_t _r = ((n) + (sz) - 1); \ 92 sector_div(_r, (sz)); \ 93 _r; \ 94 } \ 95 ) 96 97 /* 98 * ceiling(n / size) * size 99 */ 100 #define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz)) 101 102 static inline sector_t to_sector(unsigned long n) 103 { 104 return (n >> 9); 105 } 106 107 static inline unsigned long to_bytes(sector_t n) 108 { 109 return (n << 9); 110 } 111 112 int dm_split_args(int *argc, char ***argvp, char *input); 113 114 /* 115 * The device-mapper can be driven through one of two interfaces; 116 * ioctl or filesystem, depending which patch you have applied. 117 */ 118 int dm_interface_init(void); 119 void dm_interface_exit(void); 120 121 /* 122 * Targets for linear and striped mappings 123 */ 124 int dm_linear_init(void); 125 void dm_linear_exit(void); 126 127 int dm_stripe_init(void); 128 void dm_stripe_exit(void); 129 130 void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size); 131 union map_info *dm_get_mapinfo(struct bio *bio); 132 int dm_open_count(struct mapped_device *md); 133 int dm_lock_for_deletion(struct mapped_device *md); 134 135 #endif 136