1 files changed, 156 insertions, 0 deletions

diff --git a/drivers/md/dm-thin-metadata.h b/drivers/md/dm-thin-metadata.h
new file mode 100644
index 00000000000..859c1689687
--- /dev/null
+++ b/drivers/md/dm-thin-metadata.h
@@ -0,0 +1,156 @@
+/*
+ * Copyright (C) 2010-2011 Red Hat, Inc.
+ *
+ * This file is released under the GPL.
+ */
+
+#ifndef DM_THIN_METADATA_H
+#define DM_THIN_METADATA_H
+
+#include "persistent-data/dm-block-manager.h"
+
+#define THIN_METADATA_BLOCK_SIZE 4096
+
+/*----------------------------------------------------------------*/
+
+struct dm_pool_metadata;
+struct dm_thin_device;
+
+/*
+ * Device identifier
+ */
+typedef uint64_t dm_thin_id;
+
+/*
+ * Reopens or creates a new, empty metadata volume.
+ */
+struct dm_pool_metadata *dm_pool_metadata_open(struct block_device *bdev,
+                                               sector_t data_block_size);
+
+int dm_pool_metadata_close(struct dm_pool_metadata *pmd);
+
+/*
+ * Compat feature flags.  Any incompat flags beyond the ones
+ * specified below will prevent use of the thin metadata.
+ */
+#define THIN_FEATURE_COMPAT_SUPP          0UL
+#define THIN_FEATURE_COMPAT_RO_SUPP       0UL
+#define THIN_FEATURE_INCOMPAT_SUPP        0UL
+
+/*
+ * Device creation/deletion.
+ */
+int dm_pool_create_thin(struct dm_pool_metadata *pmd, dm_thin_id dev);
+
+/*
+ * An internal snapshot.
+ *
+ * You can only snapshot a quiesced origin i.e. one that is either
+ * suspended or not instanced at all.
+ */
+int dm_pool_create_snap(struct dm_pool_metadata *pmd, dm_thin_id dev,
+                        dm_thin_id origin);
+
+/*
+ * Deletes a virtual device from the metadata.  It _is_ safe to call this
+ * when that device is open.  Operations on that device will just start
+ * failing.  You still need to call close() on the device.
+ */
+int dm_pool_delete_thin_device(struct dm_pool_metadata *pmd,
+                               dm_thin_id dev);
+
+/*
+ * Commits _all_ metadata changes: device creation, deletion, mapping
+ * updates.
+ */
+int dm_pool_commit_metadata(struct dm_pool_metadata *pmd);
+
+/*
+ * Set/get userspace transaction id.
+ */
+int dm_pool_set_metadata_transaction_id(struct dm_pool_metadata *pmd,
+                                        uint64_t current_id,
+                                        uint64_t new_id);
+
+int dm_pool_get_metadata_transaction_id(struct dm_pool_metadata *pmd,
+                                        uint64_t *result);
+
+/*
+ * Hold/get root for userspace transaction.
+ */
+int dm_pool_hold_metadata_root(struct dm_pool_metadata *pmd);
+
+int dm_pool_get_held_metadata_root(struct dm_pool_metadata *pmd,
+                                   dm_block_t *result);
+
+/*
+ * Actions on a single virtual device.
+ */
+
+/*
+ * Opening the same device more than once will fail with -EBUSY.
+ */
+int dm_pool_open_thin_device(struct dm_pool_metadata *pmd, dm_thin_id dev,
+                             struct dm_thin_device **td);
+
+int dm_pool_close_thin_device(struct dm_thin_device *td);
+
+dm_thin_id dm_thin_dev_id(struct dm_thin_device *td);
+
+struct dm_thin_lookup_result {
+        dm_block_t block;
+        int shared;
+};
+
+/*
+ * Returns:
+ *   -EWOULDBLOCK iff @can_block is set and would block.
+ *   -ENODATA iff that mapping is not present.
+ *   0 success
+ */
+int dm_thin_find_block(struct dm_thin_device *td, dm_block_t block,
+                       int can_block, struct dm_thin_lookup_result *result);
+
+/*
+ * Obtain an unused block.
+ */
+int dm_pool_alloc_data_block(struct dm_pool_metadata *pmd, dm_block_t *result);
+
+/*
+ * Insert or remove block.
+ */
+int dm_thin_insert_block(struct dm_thin_device *td, dm_block_t block,
+                         dm_block_t data_block);
+
+int dm_thin_remove_block(struct dm_thin_device *td, dm_block_t block);
+
+/*
+ * Queries.
+ */
+int dm_thin_get_highest_mapped_block(struct dm_thin_device *td,
+                                     dm_block_t *highest_mapped);
+
+int dm_thin_get_mapped_count(struct dm_thin_device *td, dm_block_t *result);
+
+int dm_pool_get_free_block_count(struct dm_pool_metadata *pmd,
+                                 dm_block_t *result);
+
+int dm_pool_get_free_metadata_block_count(struct dm_pool_metadata *pmd,
+                                          dm_block_t *result);
+
+int dm_pool_get_metadata_dev_size(struct dm_pool_metadata *pmd,
+                                  dm_block_t *result);
+
+int dm_pool_get_data_block_size(struct dm_pool_metadata *pmd, sector_t *result);
+
+int dm_pool_get_data_dev_size(struct dm_pool_metadata *pmd, dm_block_t *result);
+
+/*
+ * Returns -ENOSPC if the new size is too small and already allocated
+ * blocks would be lost.
+ */
+int dm_pool_resize_data_dev(struct dm_pool_metadata *pmd, dm_block_t new_size);
+
+/*----------------------------------------------------------------*/
+
+#endif