MDEV-8195: InnoDB: Error: trying to access tablespace 11262 page no. 7,...

MDEV-8195: InnoDB: Error: trying to access tablespace 11262 page no. 7, InnoDB: but the tablespace does not exist or is just being dropped.

Analysis: Problem was that we did try to read from tablespace
that was being dropped.

Fixed by introducing a new function to find a tablespace only
if it is not being dropped currently and adding this check
before trying to read pages from tablespace.

storage/innobase/fil/fil0fil.cc

@@ -341,6 +341,26 @@ fil_space_get_by_id(
 	return(space);
 }
 
+/*******************************************************************//**
+Returns the table space by a given id, NULL if not found. */
+fil_space_t*
+fil_space_found_by_id(
+/*==================*/
+	ulint	id)	/*!< in: space id */
+{
+	fil_space_t* space = NULL;
+	mutex_enter(&fil_system->mutex);
+	space = fil_space_get_by_id(id);
+
+	/* Not found if space is being deleted */
+	if (space && space->stop_new_ops) {
+		space = NULL;
+	}
+
+	mutex_exit(&fil_system->mutex);
+	return space;
+}
+
 /****************************************************************//**
 Get space id from fil node */
 ulint

storage/innobase/include/fil0fil.h

@@ -1252,6 +1252,13 @@ fil_system_exit(void);
 /*==================*/
 
 #ifndef UNIV_INNOCHECKSUM
+/*******************************************************************//**
+Returns the table space by a given id, NULL if not found. */
+fil_space_t*
+fil_space_found_by_id(
+/*==================*/
+	ulint	id);	/*!< in: space id */
+
 /*******************************************************************//**
 Returns the table space by a given id, NULL if not found. */
 fil_space_t*

storage/xtradb/fil/fil0fil.cc

@@ -344,6 +344,26 @@ fil_space_get_by_id(
 	return(space);
 }
 
+/*******************************************************************//**
+Returns the table space by a given id, NULL if not found. */
+fil_space_t*
+fil_space_found_by_id(
+/*==================*/
+	ulint	id)	/*!< in: space id */
+{
+	fil_space_t* space = NULL;
+	mutex_enter(&fil_system->mutex);
+	space = fil_space_get_by_id(id);
+
+	/* Not found if space is being deleted */
+	if (space && space->stop_new_ops) {
+		space = NULL;
+	}
+
+	mutex_exit(&fil_system->mutex);
+	return space;
+}
+
 /****************************************************************//**
 Get space id from fil node */
 ulint

storage/xtradb/include/fil0fil.h

@@ -1280,6 +1280,13 @@ fil_system_exit(void);
 /*==================*/
 
 #ifndef UNIV_INNOCHECKSUM
+/*******************************************************************//**
+Returns the table space by a given id, NULL if not found. */
+fil_space_t*
+fil_space_found_by_id(
+/*==================*/
+	ulint	id);	/*!< in: space id */
+
 /*******************************************************************//**
 Returns the table space by a given id, NULL if not found. */
 fil_space_t*