dm ioctl: refactor dm_table_complete

This change unifies the various checks and finalization that occurs on a
table prior to use.  By doing so, it allows table construction without
traversing the dm-ioctl interface.

Signed-off-by: Will Drewry <wad@chromium.org>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

3 files changed, 52 insertions, 38 deletions

diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index ed8585954a3..4d4ced8e430 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -1131,28 +1131,9 @@ static int populate_table(struct dm_table *table,
                 next = spec->next;
         }
 
-        r = dm_table_set_type(table);
-        if (r) {
-                DMWARN("unable to set table type");
-                return r;
-        }
-
         return dm_table_complete(table);
 }
 
-static int table_prealloc_integrity(struct dm_table *t,
-                                    struct mapped_device *md)
-{
-        struct list_head *devices = dm_table_get_devices(t);
-        struct dm_dev_internal *dd;
-
-        list_for_each_entry(dd, devices, list)
-                if (bdev_get_integrity(dd->dm_dev.bdev))
-                        return blk_integrity_register(dm_disk(md), NULL);
-
-        return 0;
-}
-
 static int table_load(struct dm_ioctl *param, size_t param_size)
 {
         int r;
@@ -1174,21 +1155,6 @@ static int table_load(struct dm_ioctl *param, size_t param_size)
                 goto out;
         }
 
-        r = table_prealloc_integrity(t, md);
-        if (r) {
-                DMERR("%s: could not register integrity profile.",
-                      dm_device_name(md));
-                dm_table_destroy(t);
-                goto out;
-        }
-
-        r = dm_table_alloc_md_mempools(t);
-        if (r) {
-                DMWARN("unable to allocate mempools for this table");
-                dm_table_destroy(t);
-                goto out;
-        }
-
         /* Protect md->type and md->queue against concurrent table loads. */
         dm_lock_md_type(md);
         if (dm_get_md_type(md) == DM_TYPE_NONE)
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 9924ea23032..bc60ef77a0d 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -245,7 +245,7 @@ void dm_table_destroy(struct dm_table *t)
                 msleep(1);
         smp_mb();
 
-        /* free the indexes (see dm_table_complete) */
+        /* free the indexes */
         if (t->depth >= 2)
                 vfree(t->index[t->depth - 2]);
 
@@ -778,7 +778,7 @@ int dm_table_add_target(struct dm_table *t, const char *type,
         return r;
 }
 
-int dm_table_set_type(struct dm_table *t)
+static int dm_table_set_type(struct dm_table *t)
 {
         unsigned i;
         unsigned bio_based = 0, request_based = 0;
@@ -900,7 +900,7 @@ static int setup_indexes(struct dm_table *t)
 /*
  * Builds the btree to index the map.
  */
-int dm_table_complete(struct dm_table *t)
+static int dm_table_build_index(struct dm_table *t)
 {
         int r = 0;
         unsigned int leaf_nodes;
@@ -919,6 +919,55 @@ int dm_table_complete(struct dm_table *t)
         return r;
 }
 
+/*
+ * Register the mapped device for blk_integrity support if
+ * the underlying devices support it.
+ */
+static int dm_table_prealloc_integrity(struct dm_table *t, struct mapped_device *md)
+{
+        struct list_head *devices = dm_table_get_devices(t);
+        struct dm_dev_internal *dd;
+
+        list_for_each_entry(dd, devices, list)
+                if (bdev_get_integrity(dd->dm_dev.bdev))
+                        return blk_integrity_register(dm_disk(md), NULL);
+
+        return 0;
+}
+
+/*
+ * Prepares the table for use by building the indices,
+ * setting the type, and allocating mempools.
+ */
+int dm_table_complete(struct dm_table *t)
+{
+        int r;
+
+        r = dm_table_set_type(t);
+        if (r) {
+                DMERR("unable to set table type");
+                return r;
+        }
+
+        r = dm_table_build_index(t);
+        if (r) {
+                DMERR("unable to build btrees");
+                return r;
+        }
+
+        r = dm_table_prealloc_integrity(t, t->md);
+        if (r) {
+                DMERR("could not register integrity profile.");
+                return r;
+        }
+
+        r = dm_table_alloc_md_mempools(t);
+        if (r)
+                DMERR("unable to allocate mempools");
+
+        return r;
+}
+
 static DEFINE_MUTEX(_event_lock);
 void dm_table_event_callback(struct dm_table *t,
                              void (*fn)(void *), void *context)
diff --git a/drivers/md/dm.h b/drivers/md/dm.h
index 450fbd98c48..0d7b374c5dc 100644
--- a/drivers/md/dm.h
+++ b/drivers/md/dm.h
@@ -59,7 +59,6 @@ void dm_table_postsuspend_targets(struct dm_table *t);
 int dm_table_resume_targets(struct dm_table *t);
 int dm_table_any_congested(struct dm_table *t, int bdi_bits);
 int dm_table_any_busy_target(struct dm_table *t);
-int dm_table_set_type(struct dm_table *t);
 unsigned dm_table_get_type(struct dm_table *t);
 bool dm_table_request_based(struct dm_table *t);
 int dm_table_alloc_md_mempools(struct dm_table *t);