[PATCH v4 7/9] libxc: split p2m allocation in domain builder from other magic pages

[Juergen Gross <jgross@suse.com>]

Carve out the p2m list allocation from the .alloc_magic_pages hook of
the domain builder in order to prepare allocating the p2m list outside
of the initial kernel mapping. This will be needed to support loading
domains with huge memory (>512 GB).

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
---
 tools/libxc/include/xc_dom.h |  1 +
 tools/libxc/xc_dom_core.c    |  3 +++
 tools/libxc/xc_dom_x86.c     | 11 ++++++++++-
 3 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/tools/libxc/include/xc_dom.h b/tools/libxc/include/xc_dom.h
index 2358012..7c157c3 100644
--- a/tools/libxc/include/xc_dom.h
+++ b/tools/libxc/include/xc_dom.h
@@ -221,6 +221,7 @@ struct xc_dom_arch {
     /* pagetable setup */
     int (*alloc_magic_pages) (struct xc_dom_image * dom);
     int (*alloc_pgtables) (struct xc_dom_image * dom);
+    int (*alloc_p2m_list) (struct xc_dom_image * dom);
     int (*setup_pgtables) (struct xc_dom_image * dom);
 
     /* arch-specific data structs setup */
diff --git a/tools/libxc/xc_dom_core.c b/tools/libxc/xc_dom_core.c
index 7b48b1f..ad91b35 100644
--- a/tools/libxc/xc_dom_core.c
+++ b/tools/libxc/xc_dom_core.c
@@ -1096,6 +1096,9 @@ int xc_dom_build_image(struct xc_dom_image *dom)
     }
 
     /* allocate other pages */
+    if ( dom->arch_hooks->alloc_p2m_list &&
+         dom->arch_hooks->alloc_p2m_list(dom) != 0 )
+        goto err;
     if ( dom->arch_hooks->alloc_magic_pages(dom) != 0 )
         goto err;
     if ( dom->arch_hooks->alloc_pgtables(dom) != 0 )
diff --git a/tools/libxc/xc_dom_x86.c b/tools/libxc/xc_dom_x86.c
index 3c6bb9c..dd448cb 100644
--- a/tools/libxc/xc_dom_x86.c
+++ b/tools/libxc/xc_dom_x86.c
@@ -475,7 +475,7 @@ pfn_error:
 
 /* ------------------------------------------------------------------------ */
 
-static int alloc_magic_pages(struct xc_dom_image *dom)
+static int alloc_p2m_list(struct xc_dom_image *dom)
 {
     size_t p2m_alloc_size = dom->p2m_size * dom->arch_hooks->sizeof_pfn;
 
@@ -487,6 +487,13 @@ static int alloc_magic_pages(struct xc_dom_image *dom)
     if ( dom->p2m_guest == NULL )
         return -1;
 
+    return 0;
+}
+
+/* ------------------------------------------------------------------------ */
+
+static int alloc_magic_pages(struct xc_dom_image *dom)
+{
     /* allocate special pages */
     dom->start_info_pfn = xc_dom_alloc_page(dom, "start info");
     dom->xenstore_pfn = xc_dom_alloc_page(dom, "xenstore");
@@ -1667,6 +1674,7 @@ static struct xc_dom_arch xc_dom_32_pae = {
     .arch_private_size = sizeof(struct xc_dom_image_x86),
     .alloc_magic_pages = alloc_magic_pages,
     .alloc_pgtables = alloc_pgtables_x86_32_pae,
+    .alloc_p2m_list = alloc_p2m_list,
     .setup_pgtables = setup_pgtables_x86_32_pae,
     .start_info = start_info_x86_32,
     .shared_info = shared_info_x86_32,
@@ -1684,6 +1692,7 @@ static struct xc_dom_arch xc_dom_64 = {
     .arch_private_size = sizeof(struct xc_dom_image_x86),
     .alloc_magic_pages = alloc_magic_pages,
     .alloc_pgtables = alloc_pgtables_x86_64,
+    .alloc_p2m_list = alloc_p2m_list,
     .setup_pgtables = setup_pgtables_x86_64,
     .start_info = start_info_x86_64,
     .shared_info = shared_info_x86_64,
-- 
2.1.4