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Diffstat (limited to 'drivers/md/dm-snap.h')
-rw-r--r--drivers/md/dm-snap.h163
1 files changed, 0 insertions, 163 deletions
diff --git a/drivers/md/dm-snap.h b/drivers/md/dm-snap.h
deleted file mode 100644
index fdec1e2dc87..00000000000
--- a/drivers/md/dm-snap.h
+++ /dev/null
@@ -1,163 +0,0 @@
-/*
- * dm-snapshot.c
- *
- * Copyright (C) 2001-2002 Sistina Software (UK) Limited.
- *
- * This file is released under the GPL.
- */
-
-#ifndef DM_SNAPSHOT_H
-#define DM_SNAPSHOT_H
-
-#include "dm.h"
-#include <linux/blkdev.h>
-
-struct exception_table {
- uint32_t hash_mask;
- struct list_head *table;
-};
-
-/*
- * The snapshot code deals with largish chunks of the disk at a
- * time. Typically 64k - 256k.
- */
-/* FIXME: can we get away with limiting these to a uint32_t ? */
-typedef sector_t chunk_t;
-
-/*
- * An exception is used where an old chunk of data has been
- * replaced by a new one.
- */
-struct 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 exception_store {
-
- /*
- * Destroys this object when you've finished with it.
- */
- void (*destroy) (struct exception_store *store);
-
- /*
- * The target shouldn't read the COW device until this is
- * called.
- */
- int (*read_metadata) (struct exception_store *store);
-
- /*
- * Find somewhere to store the next exception.
- */
- int (*prepare_exception) (struct exception_store *store,
- struct exception *e);
-
- /*
- * Update the metadata with this exception.
- */
- void (*commit_exception) (struct exception_store *store,
- struct exception *e,
- void (*callback) (void *, int success),
- void *callback_context);
-
- /*
- * The snapshot is invalid, note this in the metadata.
- */
- void (*drop_snapshot) (struct exception_store *store);
-
- /*
- * Return how full the snapshot is.
- */
- void (*fraction_full) (struct exception_store *store,
- sector_t *numerator,
- sector_t *denominator);
-
- struct dm_snapshot *snap;
- void *context;
-};
-
-struct dm_snapshot {
- struct rw_semaphore lock;
- struct dm_table *table;
-
- struct dm_dev *origin;
- struct dm_dev *cow;
-
- /* List of snapshots per Origin */
- struct list_head list;
-
- /* Size of data blocks saved - must be a power of 2 */
- chunk_t chunk_size;
- chunk_t chunk_mask;
- chunk_t chunk_shift;
-
- /* You can't use a snapshot if this is 0 (e.g. if full) */
- int valid;
-
- /* Origin writes don't trigger exceptions until this is set */
- int active;
-
- /* Used for display of table */
- char type;
-
- /* The last percentage we notified */
- int last_percent;
-
- struct exception_table pending;
- struct exception_table complete;
-
- /* The on disk metadata handler */
- struct exception_store store;
-
- struct kcopyd_client *kcopyd_client;
-};
-
-/*
- * Used by the exception stores to load exceptions hen
- * initialising.
- */
-int dm_add_exception(struct dm_snapshot *s, chunk_t old, chunk_t new);
-
-/*
- * Constructor and destructor for the default persistent
- * store.
- */
-int dm_create_persistent(struct exception_store *store, uint32_t chunk_size);
-
-int dm_create_transient(struct exception_store *store,
- struct dm_snapshot *s, int blocksize);
-
-/*
- * Return the number of sectors in the device.
- */
-static inline sector_t get_dev_size(struct block_device *bdev)
-{
- return bdev->bd_inode->i_size >> SECTOR_SHIFT;
-}
-
-static inline chunk_t sector_to_chunk(struct dm_snapshot *s, sector_t sector)
-{
- return (sector & ~s->chunk_mask) >> s->chunk_shift;
-}
-
-static inline sector_t chunk_to_sector(struct dm_snapshot *s, chunk_t chunk)
-{
- return chunk << s->chunk_shift;
-}
-
-static inline int bdev_equal(struct block_device *lhs, struct block_device *rhs)
-{
- /*
- * There is only ever one instance of a particular block
- * device so we can compare pointers safely.
- */
- return lhs == rhs;
-}
-
-#endif