[PATCH v3 21/52] xen: introduce CONFIG_HAS_PAGING_MEMPOOL

[Penny Zheng <Penny.Zheng@xxxxxxx>]

ARM MPU system doesn't need to use paging memory pool, as MPU memory mapping
table(xen_mpumap) at most takes only one 4KB page, which is enough to manage
the maximum 255 MPU memory regions, for all EL2 stage 1 translation and EL1
stage 2 translation.

We wrap all paging-memory-pool-related codes with new Kconfig
CONFIG_HAS_PAGING_MEMPOOL in common codes.

Signed-off-by: Penny Zheng <penny.zheng@xxxxxxx>
Signed-off-by: Wei Chen <wei.chen@xxxxxxx>
---
v3:
- new patch
---
 xen/arch/arm/Kconfig        | 1 +
 xen/arch/arm/domain.c       | 2 ++
 xen/arch/arm/domain_build.c | 2 ++
 xen/arch/arm/p2m.c          | 2 ++
 xen/arch/x86/Kconfig        | 1 +
 xen/common/Kconfig          | 3 +++
 xen/common/domctl.c         | 2 ++
 7 files changed, 13 insertions(+)

diff --git a/xen/arch/arm/Kconfig b/xen/arch/arm/Kconfig
index a88500fb50..b2710c1c31 100644
--- a/xen/arch/arm/Kconfig
+++ b/xen/arch/arm/Kconfig
@@ -62,6 +62,7 @@ source "arch/Kconfig"
 config HAS_MMU
        bool "Memory Management Unit support in a VMSA system"
        default y
+       select HAS_PAGING_MEMPOOL
        select HAS_PMAP
        select HAS_VMAP
        help
diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c
index add9929b79..7993cefceb 100644
--- a/xen/arch/arm/domain.c
+++ b/xen/arch/arm/domain.c
@@ -1072,6 +1072,7 @@ int domain_relinquish_resources(struct domain *d)
          */
         p2m_clear_root_pages(&d->arch.p2m);
 
+#ifdef CONFIG_HAS_PAGING_MEMPOOL
     PROGRESS(p2m):
         ret = p2m_teardown(d);
         if ( ret )
@@ -1081,6 +1082,7 @@ int domain_relinquish_resources(struct domain *d)
         ret = p2m_teardown_allocation(d);
         if( ret )
             return ret;
+#endif
 
     PROGRESS(done):
         break;
diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index d0d6be922d..260ef9ba6f 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -3830,11 +3830,13 @@ static int __init construct_domU(struct domain *d,
                 p2m_mem_mb << (20 - PAGE_SHIFT) :
                 domain_p2m_pages(mem, d->max_vcpus);
 
+#ifdef CONFIG_PAGING_MEMPOOL
     spin_lock(&d->arch.paging.lock);
     rc = p2m_set_allocation(d, p2m_pages, NULL);
     spin_unlock(&d->arch.paging.lock);
     if ( rc != 0 )
         return rc;
+#endif
 
     printk("*** LOADING DOMU cpus=%u memory=%#"PRIx64"KB ***\n",
            d->max_vcpus, mem);
diff --git a/xen/arch/arm/p2m.c b/xen/arch/arm/p2m.c
index b2771e0bed..e29b11334e 100644
--- a/xen/arch/arm/p2m.c
+++ b/xen/arch/arm/p2m.c
@@ -361,11 +361,13 @@ void p2m_final_teardown(struct domain *d)
      * where relinquish_p2m_mapping() has been called.
      */
 
+#ifdef CONFIG_HAS_PAGING_MEMPOOL
     ASSERT(page_list_empty(&p2m->pages));
 
     while ( p2m_teardown_allocation(d) == -ERESTART )
         continue; /* No preemption support here */
     ASSERT(page_list_empty(&d->arch.paging.p2m_freelist));
+#endif
 
     if ( p2m->root )
         free_domheap_pages(p2m->root, P2M_ROOT_ORDER);
diff --git a/xen/arch/x86/Kconfig b/xen/arch/x86/Kconfig
index 033cc2332e..082069f1cc 100644
--- a/xen/arch/x86/Kconfig
+++ b/xen/arch/x86/Kconfig
@@ -21,6 +21,7 @@ config X86
        select HAS_IOPORTS
        select HAS_KEXEC
        select HAS_NS16550
+       select HAS_PAGING_MEMPOOL
        select HAS_PASSTHROUGH
        select HAS_PCI
        select HAS_PCI_MSI
diff --git a/xen/common/Kconfig b/xen/common/Kconfig
index 2c29e89b75..019a123320 100644
--- a/xen/common/Kconfig
+++ b/xen/common/Kconfig
@@ -54,6 +54,9 @@ config HAS_IOPORTS
 config HAS_KEXEC
        bool
 
+config HAS_PAGING_MEMPOOL
+       bool
+
 config HAS_PDX
        bool
 
diff --git a/xen/common/domctl.c b/xen/common/domctl.c
index 505e29c0dc..c5442992b9 100644
--- a/xen/common/domctl.c
+++ b/xen/common/domctl.c
@@ -844,6 +844,7 @@ long do_domctl(XEN_GUEST_HANDLE_PARAM(xen_domctl_t) 
u_domctl)
         ret = iommu_do_domctl(op, d, u_domctl);
         break;
 
+#ifdef CONFIG_HAS_PAGING_MEMPOOL
     case XEN_DOMCTL_get_paging_mempool_size:
         ret = arch_get_paging_mempool_size(d, &op->u.paging_mempool.size);
         if ( !ret )
@@ -857,6 +858,7 @@ long do_domctl(XEN_GUEST_HANDLE_PARAM(xen_domctl_t) 
u_domctl)
             ret = hypercall_create_continuation(
                 __HYPERVISOR_domctl, "h", u_domctl);
         break;
+#endif
 
     default:
         ret = arch_do_domctl(op, d, u_domctl);
-- 
2.25.1