devlink: Add callback to query for snapshot id before snapshot create

To restrict the driver with the snapshot ID selection a new callback
is introduced for the driver to get the snapshot ID before creating
a new snapshot. This will also allow giving the same ID for multiple
snapshots taken of different regions on the same time.

Signed-off-by: Alex Vesker <valex@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 21 insertions, 0 deletions

diff --git a/net/core/devlink.c b/net/core/devlink.c
index cac856136ac6..6c92ddd2465d 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -4193,6 +4193,27 @@ void devlink_region_destroy(struct devlink_region *region)
 }
 EXPORT_SYMBOL_GPL(devlink_region_destroy);
 
+/**
+ *      devlink_region_shapshot_id_get - get snapshot ID
+ *
+ *      This callback should be called when adding a new snapshot,
+ *      Driver should use the same id for multiple snapshots taken
+ *      on multiple regions at the same time/by the same trigger.
+ *
+ *      @devlink: devlink
+ */
+u32 devlink_region_shapshot_id_get(struct devlink *devlink)
+{
+        u32 id;
+
+        mutex_lock(&devlink->lock);
+        id = ++devlink->snapshot_id;
+        mutex_unlock(&devlink->lock);
+
+        return id;
+}
+EXPORT_SYMBOL_GPL(devlink_region_shapshot_id_get);
+
 static int __init devlink_module_init(void)
 {
         return genl_register_family(&devlink_nl_family);