diff options
Diffstat (limited to 'ANDROID_3.4.5/drivers/md/dm-exception-store.h')
| -rw-r--r-- | ANDROID_3.4.5/drivers/md/dm-exception-store.h | 227 |
1 files changed, 0 insertions, 227 deletions
diff --git a/ANDROID_3.4.5/drivers/md/dm-exception-store.h b/ANDROID_3.4.5/drivers/md/dm-exception-store.h deleted file mode 100644 index 0b253624..00000000 --- a/ANDROID_3.4.5/drivers/md/dm-exception-store.h +++ /dev/null @@ -1,227 +0,0 @@ -/* - * Copyright (C) 2001-2002 Sistina Software (UK) Limited. - * Copyright (C) 2008 Red Hat, Inc. All rights reserved. - * - * Device-mapper snapshot exception store. - * - * This file is released under the GPL. - */ - -#ifndef _LINUX_DM_EXCEPTION_STORE -#define _LINUX_DM_EXCEPTION_STORE - -#include <linux/blkdev.h> -#include <linux/device-mapper.h> - -/* - * The snapshot code deals with largish chunks of the disk at a - * time. Typically 32k - 512k. - */ -typedef sector_t chunk_t; - -/* - * An exception is used where an old chunk of data has been - * replaced by a new one. - * If chunk_t is 64 bits in size, the top 8 bits of new_chunk hold the number - * of chunks that follow contiguously. Remaining bits hold the number of the - * chunk within the device. - */ -struct dm_exception { - struct list_head hash_list; - - chunk_t old_chunk; - chunk_t new_chunk; -}; - -/* - * Abstraction to handle the meta/layout of exception stores (the - * COW device). - */ -struct dm_exception_store; -struct dm_exception_store_type { - const char *name; - struct module *module; - - int (*ctr) (struct dm_exception_store *store, - unsigned argc, char **argv); - - /* - * Destroys this object when you've finished with it. - */ - void (*dtr) (struct dm_exception_store *store); - - /* - * The target shouldn't read the COW device until this is - * called. As exceptions are read from the COW, they are - * reported back via the callback. - */ - int (*read_metadata) (struct dm_exception_store *store, - int (*callback)(void *callback_context, - chunk_t old, chunk_t new), - void *callback_context); - - /* - * Find somewhere to store the next exception. - */ - int (*prepare_exception) (struct dm_exception_store *store, - struct dm_exception *e); - - /* - * Update the metadata with this exception. - */ - void (*commit_exception) (struct dm_exception_store *store, - struct dm_exception *e, - void (*callback) (void *, int success), - void *callback_context); - - /* - * Returns 0 if the exception store is empty. - * - * If there are exceptions still to be merged, sets - * *last_old_chunk and *last_new_chunk to the most recent - * still-to-be-merged chunk and returns the number of - * consecutive previous ones. - */ - int (*prepare_merge) (struct dm_exception_store *store, - chunk_t *last_old_chunk, chunk_t *last_new_chunk); - - /* - * Clear the last n exceptions. - * nr_merged must be <= the value returned by prepare_merge. - */ - int (*commit_merge) (struct dm_exception_store *store, int nr_merged); - - /* - * The snapshot is invalid, note this in the metadata. - */ - void (*drop_snapshot) (struct dm_exception_store *store); - - unsigned (*status) (struct dm_exception_store *store, - status_type_t status, char *result, - unsigned maxlen); - - /* - * Return how full the snapshot is. - */ - void (*usage) (struct dm_exception_store *store, - sector_t *total_sectors, sector_t *sectors_allocated, - sector_t *metadata_sectors); - - /* For internal device-mapper use only. */ - struct list_head list; -}; - -struct dm_snapshot; - -struct dm_exception_store { - struct dm_exception_store_type *type; - struct dm_snapshot *snap; - - /* Size of data blocks saved - must be a power of 2 */ - unsigned chunk_size; - unsigned chunk_mask; - unsigned chunk_shift; - - void *context; -}; - -/* - * Obtain the origin or cow device used by a given snapshot. - */ -struct dm_dev *dm_snap_origin(struct dm_snapshot *snap); -struct dm_dev *dm_snap_cow(struct dm_snapshot *snap); - -/* - * Funtions to manipulate consecutive chunks - */ -# if defined(CONFIG_LBDAF) || (BITS_PER_LONG == 64) -# define DM_CHUNK_CONSECUTIVE_BITS 8 -# define DM_CHUNK_NUMBER_BITS 56 - -static inline chunk_t dm_chunk_number(chunk_t chunk) -{ - return chunk & (chunk_t)((1ULL << DM_CHUNK_NUMBER_BITS) - 1ULL); -} - -static inline unsigned dm_consecutive_chunk_count(struct dm_exception *e) -{ - return e->new_chunk >> DM_CHUNK_NUMBER_BITS; -} - -static inline void dm_consecutive_chunk_count_inc(struct dm_exception *e) -{ - e->new_chunk += (1ULL << DM_CHUNK_NUMBER_BITS); - - BUG_ON(!dm_consecutive_chunk_count(e)); -} - -static inline void dm_consecutive_chunk_count_dec(struct dm_exception *e) -{ - BUG_ON(!dm_consecutive_chunk_count(e)); - - e->new_chunk -= (1ULL << DM_CHUNK_NUMBER_BITS); -} - -# else -# define DM_CHUNK_CONSECUTIVE_BITS 0 - -static inline chunk_t dm_chunk_number(chunk_t chunk) -{ - return chunk; -} - -static inline unsigned dm_consecutive_chunk_count(struct dm_exception *e) -{ - return 0; -} - -static inline void dm_consecutive_chunk_count_inc(struct dm_exception *e) -{ -} - -static inline void dm_consecutive_chunk_count_dec(struct dm_exception *e) -{ -} - -# endif - -/* - * Return the number of sectors in the device. - */ -static inline sector_t get_dev_size(struct block_device *bdev) -{ - return i_size_read(bdev->bd_inode) >> SECTOR_SHIFT; -} - -static inline chunk_t sector_to_chunk(struct dm_exception_store *store, - sector_t sector) -{ - return sector >> store->chunk_shift; -} - -int dm_exception_store_type_register(struct dm_exception_store_type *type); -int dm_exception_store_type_unregister(struct dm_exception_store_type *type); - -int dm_exception_store_set_chunk_size(struct dm_exception_store *store, - unsigned chunk_size, - char **error); - -int dm_exception_store_create(struct dm_target *ti, int argc, char **argv, - struct dm_snapshot *snap, - unsigned *args_used, - struct dm_exception_store **store); -void dm_exception_store_destroy(struct dm_exception_store *store); - -int dm_exception_store_init(void); -void dm_exception_store_exit(void); - -/* - * Two exception store implementations. - */ -int dm_persistent_snapshot_init(void); -void dm_persistent_snapshot_exit(void); - -int dm_transient_snapshot_init(void); -void dm_transient_snapshot_exit(void); - -#endif /* _LINUX_DM_EXCEPTION_STORE */ |