Block matrix inner products

I have been using the following custom function to perform the multiplication of a vector by a matrix, in which each element of the vector multiplies a 3x3 block within a (3xN)x(3) matrix:

function [B] = BlockScalar(v,A)

    N=size(v,2);
    B=zeros(3*N,3);
    
    for i=1:N
        B(3*i-2:3*i,:) = v(i).*A(3*i-2:3*i,:);
    end
    
end

Similarly, when I want to multiply a collection of 3x3 matrices by a collection of 3x3 vectors, I use the following

function [B] = BlockMatrix(A,u)

    N=size(u,2);
    B=zeros(N,3);

    for i=1:N
        B(i,:) = A(3*i-2:3*i,:)*u(:,i);
    end
    
end

Since I call them very often, these unfortunately, slow down the running of my code significantly. I was wondering if there was a more efficient (perhaps vectorised) version of the above operations.