diff options
Diffstat (limited to 'drivers/md/dm.h')
-rw-r--r-- | drivers/md/dm.h | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/drivers/md/dm.h b/drivers/md/dm.h new file mode 100644 index 000000000000..e38c3fc1a1db --- /dev/null +++ b/drivers/md/dm.h @@ -0,0 +1,195 @@ +/* + * Internal header file for device mapper + * + * Copyright (C) 2001, 2002 Sistina Software + * Copyright (C) 2004 Red Hat, Inc. All rights reserved. + * + * This file is released under the LGPL. + */ + +#ifndef DM_INTERNAL_H +#define DM_INTERNAL_H + +#include <linux/fs.h> +#include <linux/device-mapper.h> +#include <linux/list.h> +#include <linux/blkdev.h> + +#define DM_NAME "device-mapper" +#define DMWARN(f, x...) printk(KERN_WARNING DM_NAME ": " f "\n" , ## x) +#define DMERR(f, x...) printk(KERN_ERR DM_NAME ": " f "\n" , ## x) +#define DMINFO(f, x...) printk(KERN_INFO DM_NAME ": " f "\n" , ## x) + +#define DMEMIT(x...) sz += ((sz >= maxlen) ? \ + 0 : scnprintf(result + sz, maxlen - sz, x)) + +/* + * FIXME: I think this should be with the definition of sector_t + * in types.h. + */ +#ifdef CONFIG_LBD +#define SECTOR_FORMAT "%Lu" +#else +#define SECTOR_FORMAT "%lu" +#endif + +#define SECTOR_SHIFT 9 + +/* + * List of devices that a metadevice uses and should open/close. + */ +struct dm_dev { + struct list_head list; + + atomic_t count; + int mode; + struct block_device *bdev; + char name[16]; +}; + +struct dm_table; +struct mapped_device; + +/*----------------------------------------------------------------- + * Functions for manipulating a struct mapped_device. + * Drop the reference with dm_put when you finish with the object. + *---------------------------------------------------------------*/ +int dm_create(struct mapped_device **md); +int dm_create_with_minor(unsigned int minor, struct mapped_device **md); +void dm_set_mdptr(struct mapped_device *md, void *ptr); +void *dm_get_mdptr(dev_t dev); + +/* + * Reference counting for md. + */ +void dm_get(struct mapped_device *md); +void dm_put(struct mapped_device *md); + +/* + * A device can still be used while suspended, but I/O is deferred. + */ +int dm_suspend(struct mapped_device *md); +int dm_resume(struct mapped_device *md); + +/* + * The device must be suspended before calling this method. + */ +int dm_swap_table(struct mapped_device *md, struct dm_table *t); + +/* + * Drop a reference on the table when you've finished with the + * result. + */ +struct dm_table *dm_get_table(struct mapped_device *md); + +/* + * Event functions. + */ +uint32_t dm_get_event_nr(struct mapped_device *md); +int dm_wait_event(struct mapped_device *md, int event_nr); + +/* + * Info functions. + */ +struct gendisk *dm_disk(struct mapped_device *md); +int dm_suspended(struct mapped_device *md); + +/*----------------------------------------------------------------- + * Functions for manipulating a table. Tables are also reference + * counted. + *---------------------------------------------------------------*/ +int dm_table_create(struct dm_table **result, int mode, unsigned num_targets); + +void dm_table_get(struct dm_table *t); +void dm_table_put(struct dm_table *t); + +int dm_table_add_target(struct dm_table *t, const char *type, + sector_t start, sector_t len, char *params); +int dm_table_complete(struct dm_table *t); +void dm_table_event_callback(struct dm_table *t, + void (*fn)(void *), void *context); +void dm_table_event(struct dm_table *t); +sector_t dm_table_get_size(struct dm_table *t); +struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index); +struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector); +void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q); +unsigned int dm_table_get_num_targets(struct dm_table *t); +struct list_head *dm_table_get_devices(struct dm_table *t); +int dm_table_get_mode(struct dm_table *t); +void dm_table_presuspend_targets(struct dm_table *t); +void dm_table_postsuspend_targets(struct dm_table *t); +void dm_table_resume_targets(struct dm_table *t); +int dm_table_any_congested(struct dm_table *t, int bdi_bits); +void dm_table_unplug_all(struct dm_table *t); +int dm_table_flush_all(struct dm_table *t); + +/*----------------------------------------------------------------- + * A registry of target types. + *---------------------------------------------------------------*/ +int dm_target_init(void); +void dm_target_exit(void); +struct target_type *dm_get_target_type(const char *name); +void dm_put_target_type(struct target_type *t); +int dm_target_iterate(void (*iter_func)(struct target_type *tt, + void *param), void *param); + + +/*----------------------------------------------------------------- + * Useful inlines. + *---------------------------------------------------------------*/ +static inline int array_too_big(unsigned long fixed, unsigned long obj, + unsigned long num) +{ + return (num > (ULONG_MAX - fixed) / obj); +} + +/* + * Ceiling(n / sz) + */ +#define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz)) + +#define dm_sector_div_up(n, sz) ( \ +{ \ + sector_t _r = ((n) + (sz) - 1); \ + sector_div(_r, (sz)); \ + _r; \ +} \ +) + +/* + * ceiling(n / size) * size + */ +#define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz)) + +static inline sector_t to_sector(unsigned long n) +{ + return (n >> 9); +} + +static inline unsigned long to_bytes(sector_t n) +{ + return (n << 9); +} + +int dm_split_args(int *argc, char ***argvp, char *input); + +/* + * The device-mapper can be driven through one of two interfaces; + * ioctl or filesystem, depending which patch you have applied. + */ +int dm_interface_init(void); +void dm_interface_exit(void); + +/* + * Targets for linear and striped mappings + */ +int dm_linear_init(void); +void dm_linear_exit(void); + +int dm_stripe_init(void); +void dm_stripe_exit(void); + +void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size); +union map_info *dm_get_mapinfo(struct bio *bio); + +#endif |