Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm

* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm: (36 commits)
  dm: set queue ordered mode
  dm: move wait queue declaration
  dm: merge pushback and deferred bio lists
  dm: allow uninterruptible wait for pending io
  dm: merge __flush_deferred_io into caller
  dm: move bio_io_error into __split_and_process_bio
  dm: rename __split_bio
  dm: remove unnecessary struct dm_wq_req
  dm: remove unnecessary work queue context field
  dm: remove unnecessary work queue type field
  dm: bio list add bio_list_add_head
  dm snapshot: persistent fix dtr cleanup
  dm snapshot: move status to exception store
  dm snapshot: move ctr parsing to exception store
  dm snapshot: use DMEMIT macro for status
  dm snapshot: remove dm_snap header
  dm snapshot: remove dm_snap header use
  dm exception store: move cow pointer
  dm exception store: move chunk_fields
  dm exception store: move dm_target pointer
  ...

1 files changed, 49 insertions, 9 deletions

diff --git a/drivers/md/dm-exception-store.h b/drivers/md/dm-exception-store.h
index bb9f33d5daa2..0a2e6e7f67b3 100644
--- a/drivers/md/dm-exception-store.h
+++ b/drivers/md/dm-exception-store.h
@@ -37,11 +37,18 @@ struct dm_snap_exception {
  * Abstraction to handle the meta/layout of exception stores (the
  * COW device).
  */
-struct dm_exception_store {
+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 (*destroy) (struct dm_exception_store *store);
+        void (*dtr) (struct dm_exception_store *store);
 
         /*
          * The target shouldn't read the COW device until this is
@@ -72,8 +79,9 @@ struct dm_exception_store {
          */
         void (*drop_snapshot) (struct dm_exception_store *store);
 
-        int (*status) (struct dm_exception_store *store, status_type_t status,
-                       char *result, unsigned int maxlen);
+        unsigned (*status) (struct dm_exception_store *store,
+                            status_type_t status, char *result,
+                            unsigned maxlen);
 
         /*
          * Return how full the snapshot is.
@@ -82,7 +90,21 @@ struct dm_exception_store {
                                sector_t *numerator,
                                sector_t *denominator);
 
-        struct dm_snapshot *snap;
+        /* For internal device-mapper use only. */
+        struct list_head list;
+};
+
+struct dm_exception_store {
+        struct dm_exception_store_type *type;
+        struct dm_target *ti;
+
+        struct dm_dev *cow;
+
+        /* Size of data blocks saved - must be a power of 2 */
+        chunk_t chunk_size;
+        chunk_t chunk_mask;
+        chunk_t chunk_shift;
+
         void *context;
 };
 
@@ -129,6 +151,28 @@ static inline void dm_consecutive_chunk_count_inc(struct dm_snap_exception *e)
 
 #  endif
 
+/*
+ * 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_exception_store *store,
+                                      sector_t sector)
+{
+        return (sector & ~store->chunk_mask) >> 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_create(struct dm_target *ti, int argc, char **argv,
+                              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);
 
@@ -141,8 +185,4 @@ void dm_persistent_snapshot_exit(void);
 int dm_transient_snapshot_init(void);
 void dm_transient_snapshot_exit(void);
 
-int dm_create_persistent(struct dm_exception_store *store);
-
-int dm_create_transient(struct dm_exception_store *store);
-
 #endif /* _LINUX_DM_EXCEPTION_STORE */