1 files changed, 0 insertions, 898 deletions

diff --git a/ANDROID_3.4.5/drivers/md/dm-snap-persistent.c b/ANDROID_3.4.5/drivers/md/dm-snap-persistent.c
deleted file mode 100644
index 3ac41567..00000000
--- a/ANDROID_3.4.5/drivers/md/dm-snap-persistent.c
+++ /dev/null
@@ -1,898 +0,0 @@
-/*
- * Copyright (C) 2001-2002 Sistina Software (UK) Limited.
- * Copyright (C) 2006-2008 Red Hat GmbH
- *
- * This file is released under the GPL.
- */
-
-#include "dm-exception-store.h"
-
-#include <linux/mm.h>
-#include <linux/pagemap.h>
-#include <linux/vmalloc.h>
-#include <linux/export.h>
-#include <linux/slab.h>
-#include <linux/dm-io.h>
-
-#define DM_MSG_PREFIX "persistent snapshot"
-#define DM_CHUNK_SIZE_DEFAULT_SECTORS 32	/* 16KB */
-
-/*-----------------------------------------------------------------
- * Persistent snapshots, by persistent we mean that the snapshot
- * will survive a reboot.
- *---------------------------------------------------------------*/
-
-/*
- * We need to store a record of which parts of the origin have
- * been copied to the snapshot device.  The snapshot code
- * requires that we copy exception chunks to chunk aligned areas
- * of the COW store.  It makes sense therefore, to store the
- * metadata in chunk size blocks.
- *
- * There is no backward or forward compatibility implemented,
- * snapshots with different disk versions than the kernel will
- * not be usable.  It is expected that "lvcreate" will blank out
- * the start of a fresh COW device before calling the snapshot
- * constructor.
- *
- * The first chunk of the COW device just contains the header.
- * After this there is a chunk filled with exception metadata,
- * followed by as many exception chunks as can fit in the
- * metadata areas.
- *
- * All on disk structures are in little-endian format.  The end
- * of the exceptions info is indicated by an exception with a
- * new_chunk of 0, which is invalid since it would point to the
- * header chunk.
- */
-
-/*
- * Magic for persistent snapshots: "SnAp" - Feeble isn't it.
- */
-#define SNAP_MAGIC 0x70416e53
-
-/*
- * The on-disk version of the metadata.
- */
-#define SNAPSHOT_DISK_VERSION 1
-
-#define NUM_SNAPSHOT_HDR_CHUNKS 1
-
-struct disk_header {
-	__le32 magic;
-
-	/*
-	 * Is this snapshot valid.  There is no way of recovering
-	 * an invalid snapshot.
-	 */
-	__le32 valid;
-
-	/*
-	 * Simple, incrementing version. no backward
-	 * compatibility.
-	 */
-	__le32 version;
-
-	/* In sectors */
-	__le32 chunk_size;
-} __packed;
-
-struct disk_exception {
-	__le64 old_chunk;
-	__le64 new_chunk;
-} __packed;
-
-struct core_exception {
-	uint64_t old_chunk;
-	uint64_t new_chunk;
-};
-
-struct commit_callback {
-	void (*callback)(void *, int success);
-	void *context;
-};
-
-/*
- * The top level structure for a persistent exception store.
- */
-struct pstore {
-	struct dm_exception_store *store;
-	int version;
-	int valid;
-	uint32_t exceptions_per_area;
-
-	/*
-	 * Now that we have an asynchronous kcopyd there is no
-	 * need for large chunk sizes, so it wont hurt to have a
-	 * whole chunks worth of metadata in memory at once.
-	 */
-	void *area;
-
-	/*
-	 * An area of zeros used to clear the next area.
-	 */
-	void *zero_area;
-
-	/*
-	 * An area used for header. The header can be written
-	 * concurrently with metadata (when invalidating the snapshot),
-	 * so it needs a separate buffer.
-	 */
-	void *header_area;
-
-	/*
-	 * Used to keep track of which metadata area the data in
-	 * 'chunk' refers to.
-	 */
-	chunk_t current_area;
-
-	/*
-	 * The next free chunk for an exception.
-	 *
-	 * When creating exceptions, all the chunks here and above are
-	 * free.  It holds the next chunk to be allocated.  On rare
-	 * occasions (e.g. after a system crash) holes can be left in
-	 * the exception store because chunks can be committed out of
-	 * order.
-	 *
-	 * When merging exceptions, it does not necessarily mean all the
-	 * chunks here and above are free.  It holds the value it would
-	 * have held if all chunks had been committed in order of
-	 * allocation.  Consequently the value may occasionally be
-	 * slightly too low, but since it's only used for 'status' and
-	 * it can never reach its minimum value too early this doesn't
-	 * matter.
-	 */
-
-	chunk_t next_free;
-
-	/*
-	 * The index of next free exception in the current
-	 * metadata area.
-	 */
-	uint32_t current_committed;
-
-	atomic_t pending_count;
-	uint32_t callback_count;
-	struct commit_callback *callbacks;
-	struct dm_io_client *io_client;
-
-	struct workqueue_struct *metadata_wq;
-};
-
-static int alloc_area(struct pstore *ps)
-{
-	int r = -ENOMEM;
-	size_t len;
-
-	len = ps->store->chunk_size << SECTOR_SHIFT;
-
-	/*
-	 * Allocate the chunk_size block of memory that will hold
-	 * a single metadata area.
-	 */
-	ps->area = vmalloc(len);
-	if (!ps->area)
-		goto err_area;
-
-	ps->zero_area = vzalloc(len);
-	if (!ps->zero_area)
-		goto err_zero_area;
-
-	ps->header_area = vmalloc(len);
-	if (!ps->header_area)
-		goto err_header_area;
-
-	return 0;
-
-err_header_area:
-	vfree(ps->zero_area);
-
-err_zero_area:
-	vfree(ps->area);
-
-err_area:
-	return r;
-}
-
-static void free_area(struct pstore *ps)
-{
-	if (ps->area)
-		vfree(ps->area);
-	ps->area = NULL;
-
-	if (ps->zero_area)
-		vfree(ps->zero_area);
-	ps->zero_area = NULL;
-
-	if (ps->header_area)
-		vfree(ps->header_area);
-	ps->header_area = NULL;
-}
-
-struct mdata_req {
-	struct dm_io_region *where;
-	struct dm_io_request *io_req;
-	struct work_struct work;
-	int result;
-};
-
-static void do_metadata(struct work_struct *work)
-{
-	struct mdata_req *req = container_of(work, struct mdata_req, work);
-
-	req->result = dm_io(req->io_req, 1, req->where, NULL);
-}
-
-/*
- * Read or write a chunk aligned and sized block of data from a device.
- */
-static int chunk_io(struct pstore *ps, void *area, chunk_t chunk, int rw,
-		    int metadata)
-{
-	struct dm_io_region where = {
-		.bdev = dm_snap_cow(ps->store->snap)->bdev,
-		.sector = ps->store->chunk_size * chunk,
-		.count = ps->store->chunk_size,
-	};
-	struct dm_io_request io_req = {
-		.bi_rw = rw,
-		.mem.type = DM_IO_VMA,
-		.mem.ptr.vma = area,
-		.client = ps->io_client,
-		.notify.fn = NULL,
-	};
-	struct mdata_req req;
-
-	if (!metadata)
-		return dm_io(&io_req, 1, &where, NULL);
-
-	req.where = &where;
-	req.io_req = &io_req;
-
-	/*
-	 * Issue the synchronous I/O from a different thread
-	 * to avoid generic_make_request recursion.
-	 */
-	INIT_WORK_ONSTACK(&req.work, do_metadata);
-	queue_work(ps->metadata_wq, &req.work);
-	flush_work(&req.work);
-
-	return req.result;
-}
-
-/*
- * Convert a metadata area index to a chunk index.
- */
-static chunk_t area_location(struct pstore *ps, chunk_t area)
-{
-	return NUM_SNAPSHOT_HDR_CHUNKS + ((ps->exceptions_per_area + 1) * area);
-}
-
-/*
- * Read or write a metadata area.  Remembering to skip the first
- * chunk which holds the header.
- */
-static int area_io(struct pstore *ps, int rw)
-{
-	int r;
-	chunk_t chunk;
-
-	chunk = area_location(ps, ps->current_area);
-
-	r = chunk_io(ps, ps->area, chunk, rw, 0);
-	if (r)
-		return r;
-
-	return 0;
-}
-
-static void zero_memory_area(struct pstore *ps)
-{
-	memset(ps->area, 0, ps->store->chunk_size << SECTOR_SHIFT);
-}
-
-static int zero_disk_area(struct pstore *ps, chunk_t area)
-{
-	return chunk_io(ps, ps->zero_area, area_location(ps, area), WRITE, 0);
-}
-
-static int read_header(struct pstore *ps, int *new_snapshot)
-{
-	int r;
-	struct disk_header *dh;
-	unsigned chunk_size;
-	int chunk_size_supplied = 1;
-	char *chunk_err;
-
-	/*
-	 * Use default chunk size (or logical_block_size, if larger)
-	 * if none supplied
-	 */
-	if (!ps->store->chunk_size) {
-		ps->store->chunk_size = max(DM_CHUNK_SIZE_DEFAULT_SECTORS,
-		    bdev_logical_block_size(dm_snap_cow(ps->store->snap)->
-					    bdev) >> 9);
-		ps->store->chunk_mask = ps->store->chunk_size - 1;
-		ps->store->chunk_shift = ffs(ps->store->chunk_size) - 1;
-		chunk_size_supplied = 0;
-	}
-
-	ps->io_client = dm_io_client_create();
-	if (IS_ERR(ps->io_client))
-		return PTR_ERR(ps->io_client);
-
-	r = alloc_area(ps);
-	if (r)
-		return r;
-
-	r = chunk_io(ps, ps->header_area, 0, READ, 1);
-	if (r)
-		goto bad;
-
-	dh = ps->header_area;
-
-	if (le32_to_cpu(dh->magic) == 0) {
-		*new_snapshot = 1;
-		return 0;
-	}
-
-	if (le32_to_cpu(dh->magic) != SNAP_MAGIC) {
-		DMWARN("Invalid or corrupt snapshot");
-		r = -ENXIO;
-		goto bad;
-	}
-
-	*new_snapshot = 0;
-	ps->valid = le32_to_cpu(dh->valid);
-	ps->version = le32_to_cpu(dh->version);
-	chunk_size = le32_to_cpu(dh->chunk_size);
-
-	if (ps->store->chunk_size == chunk_size)
-		return 0;
-
-	if (chunk_size_supplied)
-		DMWARN("chunk size %u in device metadata overrides "
-		       "table chunk size of %u.",
-		       chunk_size, ps->store->chunk_size);
-
-	/* We had a bogus chunk_size. Fix stuff up. */
-	free_area(ps);
-
-	r = dm_exception_store_set_chunk_size(ps->store, chunk_size,
-					      &chunk_err);
-	if (r) {
-		DMERR("invalid on-disk chunk size %u: %s.",
-		      chunk_size, chunk_err);
-		return r;
-	}
-
-	r = alloc_area(ps);
-	return r;
-
-bad:
-	free_area(ps);
-	return r;
-}
-
-static int write_header(struct pstore *ps)
-{
-	struct disk_header *dh;
-
-	memset(ps->header_area, 0, ps->store->chunk_size << SECTOR_SHIFT);
-
-	dh = ps->header_area;
-	dh->magic = cpu_to_le32(SNAP_MAGIC);
-	dh->valid = cpu_to_le32(ps->valid);
-	dh->version = cpu_to_le32(ps->version);
-	dh->chunk_size = cpu_to_le32(ps->store->chunk_size);
-
-	return chunk_io(ps, ps->header_area, 0, WRITE, 1);
-}
-
-/*
- * Access functions for the disk exceptions, these do the endian conversions.
- */
-static struct disk_exception *get_exception(struct pstore *ps, uint32_t index)
-{
-	BUG_ON(index >= ps->exceptions_per_area);
-
-	return ((struct disk_exception *) ps->area) + index;
-}
-
-static void read_exception(struct pstore *ps,
-			   uint32_t index, struct core_exception *result)
-{
-	struct disk_exception *de = get_exception(ps, index);
-
-	/* copy it */
-	result->old_chunk = le64_to_cpu(de->old_chunk);
-	result->new_chunk = le64_to_cpu(de->new_chunk);
-}
-
-static void write_exception(struct pstore *ps,
-			    uint32_t index, struct core_exception *e)
-{
-	struct disk_exception *de = get_exception(ps, index);
-
-	/* copy it */
-	de->old_chunk = cpu_to_le64(e->old_chunk);
-	de->new_chunk = cpu_to_le64(e->new_chunk);
-}
-
-static void clear_exception(struct pstore *ps, uint32_t index)
-{
-	struct disk_exception *de = get_exception(ps, index);
-
-	/* clear it */
-	de->old_chunk = 0;
-	de->new_chunk = 0;
-}
-
-/*
- * Registers the exceptions that are present in the current area.
- * 'full' is filled in to indicate if the area has been
- * filled.
- */
-static int insert_exceptions(struct pstore *ps,
-			     int (*callback)(void *callback_context,
-					     chunk_t old, chunk_t new),
-			     void *callback_context,
-			     int *full)
-{
-	int r;
-	unsigned int i;
-	struct core_exception e;
-
-	/* presume the area is full */
-	*full = 1;
-
-	for (i = 0; i < ps->exceptions_per_area; i++) {
-		read_exception(ps, i, &e);
-
-		/*
-		 * If the new_chunk is pointing at the start of
-		 * the COW device, where the first metadata area
-		 * is we know that we've hit the end of the
-		 * exceptions.  Therefore the area is not full.
-		 */
-		if (e.new_chunk == 0LL) {
-			ps->current_committed = i;
-			*full = 0;
-			break;
-		}
-
-		/*
-		 * Keep track of the start of the free chunks.
-		 */
-		if (ps->next_free <= e.new_chunk)
-			ps->next_free = e.new_chunk + 1;
-
-		/*
-		 * Otherwise we add the exception to the snapshot.
-		 */
-		r = callback(callback_context, e.old_chunk, e.new_chunk);
-		if (r)
-			return r;
-	}
-
-	return 0;
-}
-
-static int read_exceptions(struct pstore *ps,
-			   int (*callback)(void *callback_context, chunk_t old,
-					   chunk_t new),
-			   void *callback_context)
-{
-	int r, full = 1;
-
-	/*
-	 * Keeping reading chunks and inserting exceptions until
-	 * we find a partially full area.
-	 */
-	for (ps->current_area = 0; full; ps->current_area++) {
-		r = area_io(ps, READ);
-		if (r)
-			return r;
-
-		r = insert_exceptions(ps, callback, callback_context, &full);
-		if (r)
-			return r;
-	}
-
-	ps->current_area--;
-
-	return 0;
-}
-
-static struct pstore *get_info(struct dm_exception_store *store)
-{
-	return (struct pstore *) store->context;
-}
-
-static void persistent_usage(struct dm_exception_store *store,
-			     sector_t *total_sectors,
-			     sector_t *sectors_allocated,
-			     sector_t *metadata_sectors)
-{
-	struct pstore *ps = get_info(store);
-
-	*sectors_allocated = ps->next_free * store->chunk_size;
-	*total_sectors = get_dev_size(dm_snap_cow(store->snap)->bdev);
-
-	/*
-	 * First chunk is the fixed header.
-	 * Then there are (ps->current_area + 1) metadata chunks, each one
-	 * separated from the next by ps->exceptions_per_area data chunks.
-	 */
-	*metadata_sectors = (ps->current_area + 1 + NUM_SNAPSHOT_HDR_CHUNKS) *
-			    store->chunk_size;
-}
-
-static void persistent_dtr(struct dm_exception_store *store)
-{
-	struct pstore *ps = get_info(store);
-
-	destroy_workqueue(ps->metadata_wq);
-
-	/* Created in read_header */
-	if (ps->io_client)
-		dm_io_client_destroy(ps->io_client);
-	free_area(ps);
-
-	/* Allocated in persistent_read_metadata */
-	if (ps->callbacks)
-		vfree(ps->callbacks);
-
-	kfree(ps);
-}
-
-static int persistent_read_metadata(struct dm_exception_store *store,
-				    int (*callback)(void *callback_context,
-						    chunk_t old, chunk_t new),
-				    void *callback_context)
-{
-	int r, uninitialized_var(new_snapshot);
-	struct pstore *ps = get_info(store);
-
-	/*
-	 * Read the snapshot header.
-	 */
-	r = read_header(ps, &new_snapshot);
-	if (r)
-		return r;
-
-	/*
-	 * Now we know correct chunk_size, complete the initialisation.
-	 */
-	ps->exceptions_per_area = (ps->store->chunk_size << SECTOR_SHIFT) /
-				  sizeof(struct disk_exception);
-	ps->callbacks = dm_vcalloc(ps->exceptions_per_area,
-				   sizeof(*ps->callbacks));
-	if (!ps->callbacks)
-		return -ENOMEM;
-
-	/*
-	 * Do we need to setup a new snapshot ?
-	 */
-	if (new_snapshot) {
-		r = write_header(ps);
-		if (r) {
-			DMWARN("write_header failed");
-			return r;
-		}
-
-		ps->current_area = 0;
-		zero_memory_area(ps);
-		r = zero_disk_area(ps, 0);
-		if (r)
-			DMWARN("zero_disk_area(0) failed");
-		return r;
-	}
-	/*
-	 * Sanity checks.
-	 */
-	if (ps->version != SNAPSHOT_DISK_VERSION) {
-		DMWARN("unable to handle snapshot disk version %d",
-		       ps->version);
-		return -EINVAL;
-	}
-
-	/*
-	 * Metadata are valid, but snapshot is invalidated
-	 */
-	if (!ps->valid)
-		return 1;
-
-	/*
-	 * Read the metadata.
-	 */
-	r = read_exceptions(ps, callback, callback_context);
-
-	return r;
-}
-
-static int persistent_prepare_exception(struct dm_exception_store *store,
-					struct dm_exception *e)
-{
-	struct pstore *ps = get_info(store);
-	uint32_t stride;
-	chunk_t next_free;
-	sector_t size = get_dev_size(dm_snap_cow(store->snap)->bdev);
-
-	/* Is there enough room ? */
-	if (size < ((ps->next_free + 1) * store->chunk_size))
-		return -ENOSPC;
-
-	e->new_chunk = ps->next_free;
-
-	/*
-	 * Move onto the next free pending, making sure to take
-	 * into account the location of the metadata chunks.
-	 */
-	stride = (ps->exceptions_per_area + 1);
-	next_free = ++ps->next_free;
-	if (sector_div(next_free, stride) == 1)
-		ps->next_free++;
-
-	atomic_inc(&ps->pending_count);
-	return 0;
-}
-
-static void persistent_commit_exception(struct dm_exception_store *store,
-					struct dm_exception *e,
-					void (*callback) (void *, int success),
-					void *callback_context)
-{
-	unsigned int i;
-	struct pstore *ps = get_info(store);
-	struct core_exception ce;
-	struct commit_callback *cb;
-
-	ce.old_chunk = e->old_chunk;
-	ce.new_chunk = e->new_chunk;
-	write_exception(ps, ps->current_committed++, &ce);
-
-	/*
-	 * Add the callback to the back of the array.  This code
-	 * is the only place where the callback array is
-	 * manipulated, and we know that it will never be called
-	 * multiple times concurrently.
-	 */
-	cb = ps->callbacks + ps->callback_count++;
-	cb->callback = callback;
-	cb->context = callback_context;
-
-	/*
-	 * If there are exceptions in flight and we have not yet
-	 * filled this metadata area there's nothing more to do.
-	 */
-	if (!atomic_dec_and_test(&ps->pending_count) &&
-	    (ps->current_committed != ps->exceptions_per_area))
-		return;
-
-	/*
-	 * If we completely filled the current area, then wipe the next one.
-	 */
-	if ((ps->current_committed == ps->exceptions_per_area) &&
-	    zero_disk_area(ps, ps->current_area + 1))
-		ps->valid = 0;
-
-	/*
-	 * Commit exceptions to disk.
-	 */
-	if (ps->valid && area_io(ps, WRITE_FLUSH_FUA))
-		ps->valid = 0;
-
-	/*
-	 * Advance to the next area if this one is full.
-	 */
-	if (ps->current_committed == ps->exceptions_per_area) {
-		ps->current_committed = 0;
-		ps->current_area++;
-		zero_memory_area(ps);
-	}
-
-	for (i = 0; i < ps->callback_count; i++) {
-		cb = ps->callbacks + i;
-		cb->callback(cb->context, ps->valid);
-	}
-
-	ps->callback_count = 0;
-}
-
-static int persistent_prepare_merge(struct dm_exception_store *store,
-				    chunk_t *last_old_chunk,
-				    chunk_t *last_new_chunk)
-{
-	struct pstore *ps = get_info(store);
-	struct core_exception ce;
-	int nr_consecutive;
-	int r;
-
-	/*
-	 * When current area is empty, move back to preceding area.
-	 */
-	if (!ps->current_committed) {
-		/*
-		 * Have we finished?
-		 */
-		if (!ps->current_area)
-			return 0;
-
-		ps->current_area--;
-		r = area_io(ps, READ);
-		if (r < 0)
-			return r;
-		ps->current_committed = ps->exceptions_per_area;
-	}
-
-	read_exception(ps, ps->current_committed - 1, &ce);
-	*last_old_chunk = ce.old_chunk;
-	*last_new_chunk = ce.new_chunk;
-
-	/*
-	 * Find number of consecutive chunks within the current area,
-	 * working backwards.
-	 */
-	for (nr_consecutive = 1; nr_consecutive < ps->current_committed;
-	     nr_consecutive++) {
-		read_exception(ps, ps->current_committed - 1 - nr_consecutive,
-			       &ce);
-		if (ce.old_chunk != *last_old_chunk - nr_consecutive ||
-		    ce.new_chunk != *last_new_chunk - nr_consecutive)
-			break;
-	}
-
-	return nr_consecutive;
-}
-
-static int persistent_commit_merge(struct dm_exception_store *store,
-				   int nr_merged)
-{
-	int r, i;
-	struct pstore *ps = get_info(store);
-
-	BUG_ON(nr_merged > ps->current_committed);
-
-	for (i = 0; i < nr_merged; i++)
-		clear_exception(ps, ps->current_committed - 1 - i);
-
-	r = area_io(ps, WRITE_FLUSH_FUA);
-	if (r < 0)
-		return r;
-
-	ps->current_committed -= nr_merged;
-
-	/*
-	 * At this stage, only persistent_usage() uses ps->next_free, so
-	 * we make no attempt to keep ps->next_free strictly accurate
-	 * as exceptions may have been committed out-of-order originally.
-	 * Once a snapshot has become merging, we set it to the value it
-	 * would have held had all the exceptions been committed in order.
-	 *
-	 * ps->current_area does not get reduced by prepare_merge() until
-	 * after commit_merge() has removed the nr_merged previous exceptions.
-	 */
-	ps->next_free = area_location(ps, ps->current_area) +
-			ps->current_committed + 1;
-
-	return 0;
-}
-
-static void persistent_drop_snapshot(struct dm_exception_store *store)
-{
-	struct pstore *ps = get_info(store);
-
-	ps->valid = 0;
-	if (write_header(ps))
-		DMWARN("write header failed");
-}
-
-static int persistent_ctr(struct dm_exception_store *store,
-			  unsigned argc, char **argv)
-{
-	struct pstore *ps;
-
-	/* allocate the pstore */
-	ps = kzalloc(sizeof(*ps), GFP_KERNEL);
-	if (!ps)
-		return -ENOMEM;
-
-	ps->store = store;
-	ps->valid = 1;
-	ps->version = SNAPSHOT_DISK_VERSION;
-	ps->area = NULL;
-	ps->zero_area = NULL;
-	ps->header_area = NULL;
-	ps->next_free = NUM_SNAPSHOT_HDR_CHUNKS + 1; /* header and 1st area */
-	ps->current_committed = 0;
-
-	ps->callback_count = 0;
-	atomic_set(&ps->pending_count, 0);
-	ps->callbacks = NULL;
-
-	ps->metadata_wq = alloc_workqueue("ksnaphd", WQ_MEM_RECLAIM, 0);
-	if (!ps->metadata_wq) {
-		kfree(ps);
-		DMERR("couldn't start header metadata update thread");
-		return -ENOMEM;
-	}
-
-	store->context = ps;
-
-	return 0;
-}
-
-static unsigned persistent_status(struct dm_exception_store *store,
-				  status_type_t status, char *result,
-				  unsigned maxlen)
-{
-	unsigned sz = 0;
-
-	switch (status) {
-	case STATUSTYPE_INFO:
-		break;
-	case STATUSTYPE_TABLE:
-		DMEMIT(" P %llu", (unsigned long long)store->chunk_size);
-	}
-
-	return sz;
-}
-
-static struct dm_exception_store_type _persistent_type = {
-	.name = "persistent",
-	.module = THIS_MODULE,
-	.ctr = persistent_ctr,
-	.dtr = persistent_dtr,
-	.read_metadata = persistent_read_metadata,
-	.prepare_exception = persistent_prepare_exception,
-	.commit_exception = persistent_commit_exception,
-	.prepare_merge = persistent_prepare_merge,
-	.commit_merge = persistent_commit_merge,
-	.drop_snapshot = persistent_drop_snapshot,
-	.usage = persistent_usage,
-	.status = persistent_status,
-};
-
-static struct dm_exception_store_type _persistent_compat_type = {
-	.name = "P",
-	.module = THIS_MODULE,
-	.ctr = persistent_ctr,
-	.dtr = persistent_dtr,
-	.read_metadata = persistent_read_metadata,
-	.prepare_exception = persistent_prepare_exception,
-	.commit_exception = persistent_commit_exception,
-	.prepare_merge = persistent_prepare_merge,
-	.commit_merge = persistent_commit_merge,
-	.drop_snapshot = persistent_drop_snapshot,
-	.usage = persistent_usage,
-	.status = persistent_status,
-};
-
-int dm_persistent_snapshot_init(void)
-{
-	int r;
-
-	r = dm_exception_store_type_register(&_persistent_type);
-	if (r) {
-		DMERR("Unable to register persistent exception store type");
-		return r;
-	}
-
-	r = dm_exception_store_type_register(&_persistent_compat_type);
-	if (r) {
-		DMERR("Unable to register old-style persistent exception "
-		      "store type");
-		dm_exception_store_type_unregister(&_persistent_type);
-		return r;
-	}
-
-	return r;
-}
-
-void dm_persistent_snapshot_exit(void)
-{
-	dm_exception_store_type_unregister(&_persistent_type);
-	dm_exception_store_type_unregister(&_persistent_compat_type);
-}