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 * Definitions of return values from target end_io function. 37 */ 38 #define DM_ENDIO_INCOMPLETE 1 39 #define DM_ENDIO_REQUEUE 2 40 41 /* 42 * Definitions of return values from target map function. 43 */ 44 #define DM_MAPIO_SUBMITTED 0 45 #define DM_MAPIO_REMAPPED 1 46 #define DM_MAPIO_REQUEUE DM_ENDIO_REQUEUE 47 48 /* 49 * Suspend feature flags 50 */ 51 #define DM_SUSPEND_LOCKFS_FLAG (1 << 0) 52 #define DM_SUSPEND_NOFLUSH_FLAG (1 << 1) 53 54 /* 55 * List of devices that a metadevice uses and should open/close. 56 */ 57 struct dm_dev { 58 struct list_head list; 59 60 atomic_t count; 61 int mode; 62 struct block_device *bdev; 63 char name[16]; 64 }; 65 66 struct dm_table; 67 68 /*----------------------------------------------------------------- 69 * Internal table functions. 70 *---------------------------------------------------------------*/ 71 void dm_table_event_callback(struct dm_table *t, 72 void (*fn)(void *), void *context); 73 struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index); 74 struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector); 75 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q); 76 struct list_head *dm_table_get_devices(struct dm_table *t); 77 void dm_table_presuspend_targets(struct dm_table *t); 78 void dm_table_postsuspend_targets(struct dm_table *t); 79 int dm_table_resume_targets(struct dm_table *t); 80 int dm_table_any_congested(struct dm_table *t, int bdi_bits); 81 void dm_table_unplug_all(struct dm_table *t); 82 int dm_table_flush_all(struct dm_table *t); 83 84 /*----------------------------------------------------------------- 85 * A registry of target types. 86 *---------------------------------------------------------------*/ 87 int dm_target_init(void); 88 void dm_target_exit(void); 89 struct target_type *dm_get_target_type(const char *name); 90 void dm_put_target_type(struct target_type *t); 91 int dm_target_iterate(void (*iter_func)(struct target_type *tt, 92 void *param), void *param); 93 94 /*----------------------------------------------------------------- 95 * Useful inlines. 96 *---------------------------------------------------------------*/ 97 static inline int array_too_big(unsigned long fixed, unsigned long obj, 98 unsigned long num) 99 { 100 return (num > (ULONG_MAX - fixed) / obj); 101 } 102 103 /* 104 * Ceiling(n / sz) 105 */ 106 #define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz)) 107 108 #define dm_sector_div_up(n, sz) ( \ 109 { \ 110 sector_t _r = ((n) + (sz) - 1); \ 111 sector_div(_r, (sz)); \ 112 _r; \ 113 } \ 114 ) 115 116 /* 117 * ceiling(n / size) * size 118 */ 119 #define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz)) 120 121 static inline sector_t to_sector(unsigned long n) 122 { 123 return (n >> 9); 124 } 125 126 static inline unsigned long to_bytes(sector_t n) 127 { 128 return (n << 9); 129 } 130 131 int dm_split_args(int *argc, char ***argvp, char *input); 132 133 /* 134 * The device-mapper can be driven through one of two interfaces; 135 * ioctl or filesystem, depending which patch you have applied. 136 */ 137 int dm_interface_init(void); 138 void dm_interface_exit(void); 139 140 /* 141 * Targets for linear and striped mappings 142 */ 143 int dm_linear_init(void); 144 void dm_linear_exit(void); 145 146 int dm_stripe_init(void); 147 void dm_stripe_exit(void); 148 149 void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size); 150 union map_info *dm_get_mapinfo(struct bio *bio); 151 int dm_open_count(struct mapped_device *md); 152 int dm_lock_for_deletion(struct mapped_device *md); 153 154 #endif 155