[IA64] Change vCPU initialization to avoid domVTi privregs memory leak

[IA64] Change vCPU initialization to avoid domVTi privregs memory leak

1) This patch moved some processing from vcpu_initialise() and
   added a new function vcpu_late_initialise().
   It executes the following initializations for VCPU of
   dom0/domU.
    - Allocate the VHPT
    - Allocate the privregs area and assign these pages into
      guest pseudo physical address space.
    - Set the tlbflush_timestamp.

   It is executed in the following sequence.

   dom0:
     start_kernel()
       ->domain_create()
       ->alloc_vcpu(VCPU0)
         ->alloc_vcpu_struct(VCPU0)
         ->vcpu_initialise(VCPU0)
       ->vcpu_late_initialise(VCPU0)

       ->construct_dom0
         ->alloc_vcpu(othe VCPUs)
           ->alloc_vcpu_struct(other VCPUs)
           ->vcpu_initialise(other VCPUs)

     ia64_hypercall(FW_HYPERCALL_IPI)
       ->fw_hypercall_ipi(XEN_SAL_BOOT_RENDEZ_VEC)
         ->arch_set_info_guest(other VCPUs)
           ->vcpu_late_initialise(other VCPUs)

   domU:
     do_domctl(XEN_DOMCTL_createdomain)
       ->domain_create()

     do_domctl(XEN_DOMCTL_max_vcpus)
       ->alloc_vcpu(all VCPUs)
         ->alloc_vcpu_struct(all VCPUs)
         ->vcpu_initialise(all VCPUs)

     do_domctl(XEN_DOMCTL_setvcpucontext)
       ->set_info_guest(VCPU0)
         ->arch_set_info_guest(VCPU0)
           ->vcpu_late_initialise(VCPU0)

     ia64_hypercall(FW_HYPERCALL_IPI)
       ->fw_hypercall_ipi(XEN_SAL_BOOT_RENDEZ_VEC)
         ->arch_set_info_guest(other VCPUs)
           ->vcpu_late_initialise(other VCPUs)

2) This patch modified the domain_set_shared_info_va().
   Currently, initialization of arch.privregs->interrupt_mask_addr
   of all VCPUs is executed in domain_set_shared_info_va().
   However, allocation of privregs area is late by modified of 1).
   Therefore, this patch modified initialization of
   arch.privregs->interrupt_mask_addr to the following sequence.

   dom0 and domU:
     ia64_hypercall(FW_HYPERCALL_SET_SHARED_INFO_VA)
       ->domain_set_shared_info_va()
         Initialize interrupt_mask_addr of VCPU0

     ia64_hypercall(FW_HYPERCALL_IPI)
       ->fw_hypercall_ipi(XEN_SAL_BOOT_RENDEZ_VEC)
         ->arch_set_info_guest(other VCPUs)
           ->vcpu_late_initialise(other VCPUs)
           Initialize interrupt_mask_addr of other VCPUs

Signed-off-by: Masaki Kanno <kanno.masaki@jp.fujitsu.com>