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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 422 | giacomo | 1 | /* |
| 2 | * Copyright (C) 2001 Sistina Software (UK) Limited. |
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| 3 | * |
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| 4 | * This file is released under the LGPL. |
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| 5 | */ |
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| 6 | |||
| 7 | #ifndef _LINUX_DEVICE_MAPPER_H |
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| 8 | #define _LINUX_DEVICE_MAPPER_H |
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| 9 | |||
| 10 | struct dm_target; |
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| 11 | struct dm_table; |
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| 12 | struct dm_dev; |
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| 13 | |||
| 14 | typedef enum { STATUSTYPE_INFO, STATUSTYPE_TABLE } status_type_t; |
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| 15 | |||
| 16 | /* |
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| 17 | * In the constructor the target parameter will already have the |
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| 18 | * table, type, begin and len fields filled in. |
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| 19 | */ |
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| 20 | typedef int (*dm_ctr_fn) (struct dm_target *target, |
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| 21 | unsigned int argc, char **argv); |
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| 22 | |||
| 23 | /* |
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| 24 | * The destructor doesn't need to free the dm_target, just |
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| 25 | * anything hidden ti->private. |
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| 26 | */ |
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| 27 | typedef void (*dm_dtr_fn) (struct dm_target *ti); |
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| 28 | |||
| 29 | /* |
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| 30 | * The map function must return: |
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| 31 | * < 0: error |
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| 32 | * = 0: The target will handle the io by resubmitting it later |
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| 33 | * > 0: simple remap complete |
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| 34 | */ |
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| 35 | typedef int (*dm_map_fn) (struct dm_target *ti, struct bio *bio); |
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| 36 | |||
| 37 | typedef void (*dm_suspend_fn) (struct dm_target *ti); |
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| 38 | typedef void (*dm_resume_fn) (struct dm_target *ti); |
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| 39 | |||
| 40 | typedef int (*dm_status_fn) (struct dm_target *ti, status_type_t status_type, |
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| 41 | char *result, unsigned int maxlen); |
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| 42 | |||
| 43 | void dm_error(const char *message); |
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| 44 | |||
| 45 | /* |
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| 46 | * Constructors should call these functions to ensure destination devices |
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| 47 | * are opened/closed correctly. |
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| 48 | * FIXME: too many arguments. |
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| 49 | */ |
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| 50 | int dm_get_device(struct dm_target *ti, const char *path, sector_t start, |
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| 51 | sector_t len, int mode, struct dm_dev **result); |
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| 52 | void dm_put_device(struct dm_target *ti, struct dm_dev *d); |
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| 53 | |||
| 54 | /* |
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| 55 | * Information about a target type |
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| 56 | */ |
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| 57 | struct target_type { |
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| 58 | const char *name; |
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| 59 | struct module *module; |
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| 60 | dm_ctr_fn ctr; |
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| 61 | dm_dtr_fn dtr; |
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| 62 | dm_map_fn map; |
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| 63 | dm_suspend_fn suspend; |
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| 64 | dm_resume_fn resume; |
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| 65 | dm_status_fn status; |
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| 66 | }; |
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| 67 | |||
| 68 | struct io_restrictions { |
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| 69 | unsigned short max_sectors; |
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| 70 | unsigned short max_phys_segments; |
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| 71 | unsigned short max_hw_segments; |
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| 72 | unsigned short hardsect_size; |
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| 73 | unsigned int max_segment_size; |
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| 74 | unsigned long seg_boundary_mask; |
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| 75 | }; |
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| 76 | |||
| 77 | struct dm_target { |
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| 78 | struct dm_table *table; |
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| 79 | struct target_type *type; |
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| 80 | |||
| 81 | /* target limits */ |
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| 82 | sector_t begin; |
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| 83 | sector_t len; |
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| 84 | |||
| 85 | /* FIXME: turn this into a mask, and merge with io_restrictions */ |
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| 86 | sector_t split_io; |
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| 87 | |||
| 88 | /* |
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| 89 | * These are automaticall filled in by |
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| 90 | * dm_table_get_device. |
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| 91 | */ |
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| 92 | struct io_restrictions limits; |
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| 93 | |||
| 94 | /* target specific data */ |
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| 95 | void *private; |
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| 96 | |||
| 97 | /* Used to provide an error string from the ctr */ |
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| 98 | char *error; |
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| 99 | }; |
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| 100 | |||
| 101 | int dm_register_target(struct target_type *t); |
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| 102 | int dm_unregister_target(struct target_type *t); |
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| 103 | |||
| 104 | #endif /* _LINUX_DEVICE_MAPPER_H */ |