ASP.NET Identity: get all users in a role

I didn't see a built in way, but it is fairly easy to implement. I have this method in my application specific UserManager:

public IQueryable<User> GetUsersInRole(string roleName)
{
    return from user in Users
           where user.Roles.Any(r => r.Role.Name == roleName)
           select user;
}

The SQL it output seemed reasonable:

SELECT 
[Extent1].[Id] AS [Id], 
[Extent1].[Email] AS [Email], 
[Extent1].[EmailConfirmed] AS [EmailConfirmed], 
[Extent1].[PasswordHash] AS [PasswordHash], 
[Extent1].[SecurityStamp] AS [SecurityStamp], 
[Extent1].[PhoneNumber] AS [PhoneNumber], 
[Extent1].[PhoneNumberConfirmed] AS [PhoneNumberConfirmed], 
[Extent1].[TwoFactorEnabled] AS [TwoFactorEnabled], 
[Extent1].[LockoutEndDateUtc] AS [LockoutEndDateUtc], 
[Extent1].[LockoutEnabled] AS [LockoutEnabled], 
[Extent1].[AccessFailedCount] AS [AccessFailedCount], 
[Extent1].[UserName] AS [UserName]
FROM [dbo].[AspNetUsers] AS [Extent1]
WHERE  EXISTS (SELECT 
    1 AS [C1]
    FROM  [dbo].[AspNetUserRoles] AS [Extent2]
    INNER JOIN [dbo].[AspNetRoles] AS [Extent3] ON [Extent2].[RoleId] = [Extent3].[Id]
    WHERE ([Extent1].[Id] = [Extent2].[UserId]) AND ([Extent3].[Name] = @p__linq__0)
)

For some reason, very nice query suggested above by @ChoptimusPrime did not compile for me in ASP.NET Identity 2.2.1. I have written an extended function:

public static IQueryable<User> GetUsersInRole(DbContext db, string roleName)
{
  if (db != null && roleName != null)
  {
    var roles = db.Roles.Where(r => r.Name == roleName);
    if (roles.Any())
    {
      var roleId = roles.First().Id;
      return from user in db.Users
             where user.Roles.Any(r => r.RoleId == roleId)
             select user;
    }
  }
  return null;
}

Its not possible via the RoleManager in 1.0 RTM, in 1.1 it will exposed via an IQueryable RoleManager.Roles. For 1.0, you need to drop down to the implementation layer (i.e. db context)