blobstore: add RPC for growing blobstore

Add num_md_pages_per_cluster_ratio parameter to bdev_lvol_create_lvstore.
Add bdev_lvol_grow_lvstore rpc.

Signed-off-by: Peng Yu <yupeng0921@gmail.com>
Change-Id: I43a129efbc1a08f9d0df027e80f63ab1393163a2
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/9734
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Broadcom CI <spdk-ci.pdl@broadcom.com>
Community-CI: Mellanox Build Bot
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>

doc/jsonrpc.md

@@ -7862,12 +7862,27 @@ Construct a logical volume store.
 
 #### Parameters
 
-Name                    | Optional | Type        | Description
+Name                          | Optional | Type        | Description
------------------------ | -------- | ----------- | -----------
+----------------------------- | -------- | ----------- | -----------
-bdev_name               | Required | string      | Bdev on which to construct logical volume store
+bdev_name                     | Required | string      | Bdev on which to construct logical volume store
-lvs_name                | Required | string      | Name of the logical volume store to create
+lvs_name                      | Required | string      | Name of the logical volume store to create
-cluster_sz              | Optional | number      | Cluster size of the logical volume store in bytes
+cluster_sz                    | Optional | number      | Cluster size of the logical volume store in bytes (Default: 4MiB)
-clear_method            | Optional | string      | Change clear method for data region. Available: none, unmap (default), write_zeroes
+clear_method                  | Optional | string      | Change clear method for data region. Available: none, unmap (default), write_zeroes
+num_md_pages_per_cluster_ratio| Optional | number      | Reserved metadata pages per cluster (Default: 100)
+
+The num_md_pages_per_cluster_ratio defines the amount of metadata to
+allocate when the logical volume store is created. The default value
+is '100', which translates to 1 4KiB per cluster. For the default 4MiB
+cluster size, this equates to about 0.1% of the underlying block
+device allocated for metadata. Logical volume stores can be grown, if
+the size of the underlying block device grows in the future, but only
+if enough metadata pages were allocated to support the growth. So
+num_md_pages_per_cluster_ratio should be set to a higher value if
+wanting to support future growth. For example,
+num_md_pages_per_cluster_ratio = 200 would support future 2x growth of
+the logical volume store, and would result in 0.2% of the underlying
+block device allocated for metadata (with a default 4MiB cluster
+size).
 
 #### Response
 

python/spdk/rpc/lvol.py

@@ -1,4 +1,5 @@
-def bdev_lvol_create_lvstore(client, bdev_name, lvs_name, cluster_sz=None, clear_method=None):
+def bdev_lvol_create_lvstore(client, bdev_name, lvs_name, cluster_sz=None,
+                             clear_method=None, num_md_pages_per_cluster_ratio=None):
     """Construct a logical volume store.
 
     Args:
@@ -6,6 +7,7 @@ def bdev_lvol_create_lvstore(client, bdev_name, lvs_name, cluster_sz=None, clear
         lvs_name: name of the logical volume store to create
         cluster_sz: cluster size of the logical volume store in bytes (optional)
         clear_method: Change clear method for data region. Available: none, unmap, write_zeroes (optional)
+        num_md_pages_per_cluster_ratio: metadata pages per cluster (optional)
 
     Returns:
         UUID of created logical volume store.
@@ -15,6 +17,8 @@ def bdev_lvol_create_lvstore(client, bdev_name, lvs_name, cluster_sz=None, clear
         params['cluster_sz'] = cluster_sz
     if clear_method:
         params['clear_method'] = clear_method
+    if num_md_pages_per_cluster_ratio:
+        params['num_md_pages_per_cluster_ratio'] = num_md_pages_per_cluster_ratio
     return client.call('bdev_lvol_create_lvstore', params)
 
 
@@ -32,6 +36,23 @@ def bdev_lvol_rename_lvstore(client, old_name, new_name):
     return client.call('bdev_lvol_rename_lvstore', params)
 
 
+def bdev_lvol_grow_lvstore(client, uuid=None, lvs_name=None):
+    """Grow the logical volume store to fill the underlying bdev
+
+    Args:
+        uuid: UUID of logical volume store to resize (optional)
+        lvs_name: name of logical volume store to resize (optional)
+    """
+    if (uuid and lvs_name):
+        raise ValueError("Exactly one of uuid or lvs_name may be specified")
+    params = {}
+    if uuid:
+        params['uuid'] = uuid
+    if lvs_name:
+        params['lvs_name'] = lvs_name
+    return client.call('bdev_lvol_grow_lvstore', params)
+
+
 def bdev_lvol_create(client, lvol_name, size, thin_provision=False, uuid=None, lvs_name=None, clear_method=None):
     """Create a logical volume on a logical volume store.
 

scripts/rpc.py

@@ -1767,7 +1767,8 @@ Format: 'user:u1 secret:s1 muser:mu1 msecret:ms1,user:u2 secret:s2 muser:mu2 mse
                                                      bdev_name=args.bdev_name,
                                                      lvs_name=args.lvs_name,
                                                      cluster_sz=args.cluster_sz,
-                                                     clear_method=args.clear_method))
+                                                     clear_method=args.clear_method,
+                                                     num_md_pages_per_cluster_ratio=args.md_pages_per_cluster_ratio))
 
     p = subparsers.add_parser('bdev_lvol_create_lvstore', help='Add logical volume store on base bdev')
     p.add_argument('bdev_name', help='base bdev name')
@@ -1775,6 +1776,7 @@ Format: 'user:u1 secret:s1 muser:mu1 msecret:ms1,user:u2 secret:s2 muser:mu2 mse
     p.add_argument('-c', '--cluster-sz', help='size of cluster (in bytes)', type=int, required=False)
     p.add_argument('--clear-method', help="""Change clear method for data region.
         Available: none, unmap, write_zeroes""", required=False)
+    p.add_argument('-m', '--md-pages-per-cluster-ratio', help='reserved metadata pages for each cluster', type=int, required=False)
     p.set_defaults(func=bdev_lvol_create_lvstore)
 
     def bdev_lvol_rename_lvstore(args):
@@ -1787,6 +1789,17 @@ Format: 'user:u1 secret:s1 muser:mu1 msecret:ms1,user:u2 secret:s2 muser:mu2 mse
     p.add_argument('new_name', help='new name')
     p.set_defaults(func=bdev_lvol_rename_lvstore)
 
+    def bdev_lvol_grow_lvstore(args):
+        print_dict(rpc.lvol.bdev_lvol_grow_lvstore(args.client,
+                                                   uuid=args.uuid,
+                                                   lvs_name=args.lvs_name))
+
+    p = subparsers.add_parser('bdev_lvol_grow_lvstore',
+                              help='Grow the lvstore size to the underlying bdev size')
+    p.add_argument('-u', '--uuid', help='lvol store UUID', required=False)
+    p.add_argument('-l', '--lvs-name', help='lvol store name', required=False)
+    p.set_defaults(func=bdev_lvol_grow_lvstore)
+
     def bdev_lvol_create(args):
         print_json(rpc.lvol.bdev_lvol_create(args.client,
                                              lvol_name=args.lvol_name,