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...) \ 22 printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg) 23 #define DMERR_LIMIT(f, arg...) \ 24 do { \ 25 if (printk_ratelimit()) \ 26 printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " \ 27 f "\n", ## arg); \ 28 } while (0) 29 30 #define DMWARN(f, arg...) \ 31 printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg) 32 #define DMWARN_LIMIT(f, arg...) \ 33 do { \ 34 if (printk_ratelimit()) \ 35 printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " \ 36 f "\n", ## arg); \ 37 } while (0) 38 39 #define DMINFO(f, arg...) \ 40 printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg) 41 #define DMINFO_LIMIT(f, arg...) \ 42 do { \ 43 if (printk_ratelimit()) \ 44 printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f \ 45 "\n", ## arg); \ 46 } while (0) 47 48 #ifdef CONFIG_DM_DEBUG 49 # define DMDEBUG(f, arg...) \ 50 printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX " DEBUG: " f "\n", ## arg) 51 # define DMDEBUG_LIMIT(f, arg...) \ 52 do { \ 53 if (printk_ratelimit()) \ 54 printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX ": " f \ 55 "\n", ## arg); \ 56 } while (0) 57 #else 58 # define DMDEBUG(f, arg...) do {} while (0) 59 # define DMDEBUG_LIMIT(f, arg...) do {} while (0) 60 #endif 61 62 #define DMEMIT(x...) sz += ((sz >= maxlen) ? \ 63 0 : scnprintf(result + sz, maxlen - sz, x)) 64 65 #define SECTOR_SHIFT 9 66 67 /* 68 * Definitions of return values from target end_io function. 69 */ 70 #define DM_ENDIO_INCOMPLETE 1 71 #define DM_ENDIO_REQUEUE 2 72 73 /* 74 * Definitions of return values from target map function. 75 */ 76 #define DM_MAPIO_SUBMITTED 0 77 #define DM_MAPIO_REMAPPED 1 78 #define DM_MAPIO_REQUEUE DM_ENDIO_REQUEUE 79 80 /* 81 * Suspend feature flags 82 */ 83 #define DM_SUSPEND_LOCKFS_FLAG (1 << 0) 84 #define DM_SUSPEND_NOFLUSH_FLAG (1 << 1) 85 86 /* 87 * List of devices that a metadevice uses and should open/close. 88 */ 89 struct dm_dev { 90 struct list_head list; 91 92 atomic_t count; 93 int mode; 94 struct block_device *bdev; 95 char name[16]; 96 }; 97 98 struct dm_table; 99 100 /*----------------------------------------------------------------- 101 * Internal table functions. 102 *---------------------------------------------------------------*/ 103 void dm_table_event_callback(struct dm_table *t, 104 void (*fn)(void *), void *context); 105 struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index); 106 struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector); 107 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q); 108 struct list_head *dm_table_get_devices(struct dm_table *t); 109 void dm_table_presuspend_targets(struct dm_table *t); 110 void dm_table_postsuspend_targets(struct dm_table *t); 111 int dm_table_resume_targets(struct dm_table *t); 112 int dm_table_any_congested(struct dm_table *t, int bdi_bits); 113 void dm_table_unplug_all(struct dm_table *t); 114 115 /*----------------------------------------------------------------- 116 * A registry of target types. 117 *---------------------------------------------------------------*/ 118 int dm_target_init(void); 119 void dm_target_exit(void); 120 struct target_type *dm_get_target_type(const char *name); 121 void dm_put_target_type(struct target_type *t); 122 int dm_target_iterate(void (*iter_func)(struct target_type *tt, 123 void *param), void *param); 124 125 /*----------------------------------------------------------------- 126 * Useful inlines. 127 *---------------------------------------------------------------*/ 128 static inline int array_too_big(unsigned long fixed, unsigned long obj, 129 unsigned long num) 130 { 131 return (num > (ULONG_MAX - fixed) / obj); 132 } 133 134 /* 135 * Ceiling(n / sz) 136 */ 137 #define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz)) 138 139 #define dm_sector_div_up(n, sz) ( \ 140 { \ 141 sector_t _r = ((n) + (sz) - 1); \ 142 sector_div(_r, (sz)); \ 143 _r; \ 144 } \ 145 ) 146 147 /* 148 * ceiling(n / size) * size 149 */ 150 #define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz)) 151 152 static inline sector_t to_sector(unsigned long n) 153 { 154 return (n >> 9); 155 } 156 157 static inline unsigned long to_bytes(sector_t n) 158 { 159 return (n << 9); 160 } 161 162 int dm_split_args(int *argc, char ***argvp, char *input); 163 164 /* 165 * The device-mapper can be driven through one of two interfaces; 166 * ioctl or filesystem, depending which patch you have applied. 167 */ 168 int dm_interface_init(void); 169 void dm_interface_exit(void); 170 171 /* 172 * Targets for linear and striped mappings 173 */ 174 int dm_linear_init(void); 175 void dm_linear_exit(void); 176 177 int dm_stripe_init(void); 178 void dm_stripe_exit(void); 179 180 void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size); 181 union map_info *dm_get_mapinfo(struct bio *bio); 182 int dm_open_count(struct mapped_device *md); 183 int dm_lock_for_deletion(struct mapped_device *md); 184 185 #endif 186