[IA64] introduce DOM0VP_get_memmap hypercall.

introduce new dom0vp hypercall, DOM0VP_get_memmap,
to get memmap of a given domain without race.

Signed-off-by: Isaku Yamahata <yamahata@xxxxxxxxxxxxx>

diff -r 088bc049f889 xen/arch/ia64/xen/dom0_ops.c
--- a/xen/arch/ia64/xen/dom0_ops.c	Thu Oct 02 15:24:18 2008 +0900
+++ b/xen/arch/ia64/xen/dom0_ops.c	Thu Oct 02 15:25:22 2008 +0900
@@ -607,6 +607,12 @@
     case IA64_DOM0VP_unexpose_foreign_p2m:
         ret = dom0vp_unexpose_foreign_p2m(d, arg0, arg1);
         break;
+    case IA64_DOM0VP_get_memmap: {
+        XEN_GUEST_HANDLE(char) hnd;
+        set_xen_guest_handle(hnd, (char*)arg1);
+        ret = dom0vp_get_memmap((domid_t)arg0, hnd);
+        break;
+    }
     default:
         ret = -1;
 		printk("unknown dom0_vp_op 0x%lx\n", cmd);
diff -r 088bc049f889 xen/arch/ia64/xen/mm.c
--- a/xen/arch/ia64/xen/mm.c	Thu Oct 02 15:24:18 2008 +0900
+++ b/xen/arch/ia64/xen/mm.c	Thu Oct 02 15:25:22 2008 +0900
@@ -2465,6 +2465,49 @@
         free_domheap_pages(page, order);
     return ret;
 }
+
+unsigned long
+dom0vp_get_memmap(domid_t domid, XEN_GUEST_HANDLE(char) buffer)
+{
+    unsigned long ret = 0;
+    struct domain *targ_d;
+
+    struct page_info *page = NULL;
+    unsigned long order;
+
+    struct xen_ia64_memmap_info *memmap_info;
+    unsigned long num_pages;
+    
+    ret = rcu_lock_target_domain_by_id(domid, &targ_d);
+    if (ret != 0)
+        return ret;
+
+    memmap_lock(targ_d);
+
+    ret = memmap_copy_from(targ_d, &page, &order);
+    if (ret != 0)
+        goto out;
+
+    memmap_info = page_to_virt(page);
+    num_pages = targ_d->shared_info->arch.memmap_info_num_pages;
+    if ((num_pages << PAGE_SHIFT) - sizeof(*memmap_info) <
+        memmap_info->efi_memmap_size) {
+        ret = -EFAULT;
+        goto out;
+    }
+    if (copy_to_guest(buffer, (char*)memmap_info, sizeof(*memmap_info)) ||
+        copy_to_guest_offset(buffer, sizeof(*memmap_info),
+                             (char*)memmap_info->memdesc,
+                             memmap_info->efi_memmap_size))
+        ret = -EFAULT;
+
+ out:
+    memmap_unlock(targ_d);
+    if (page != NULL)
+        free_domheap_pages(page, order);
+
+    return ret;
+}
 #endif
 
 // grant table host mapping
diff -r 088bc049f889 xen/include/asm-ia64/mm.h
--- a/xen/include/asm-ia64/mm.h	Thu Oct 02 15:24:18 2008 +0900
+++ b/xen/include/asm-ia64/mm.h	Thu Oct 02 15:25:22 2008 +0900
@@ -448,6 +448,7 @@
 extern void foreign_p2m_destroy(struct domain* d);
 extern unsigned long dom0vp_expose_foreign_p2m(struct domain* dest_dom, unsigned long dest_gpfn, domid_t domid, XEN_GUEST_HANDLE(char) buffer, unsigned long flags);
 extern unsigned long dom0vp_unexpose_foreign_p2m(struct domain* dest_dom, unsigned long dest_gpfn, domid_t domid);
+extern unsigned long dom0vp_get_memmap(domid_t domid, XEN_GUEST_HANDLE(char) buffer);
 #else
 #define expose_p2m_init()       do { } while (0)
 #define dom0vp_expose_p2m(d, conv_start_gpfn, assign_start_gpfn, expose_size, granule_pfn)	(-ENOSYS)
@@ -456,6 +457,7 @@
 #define dom0vp_expose_foreign_p2m(dest_dom, dest_gpfn, domid, buffer, flags)	(-ENOSYS)
 #define dom0vp_unexpose_foreign_p2m(dest_dom, dest_gpfn, domid)	(-ENOSYS)
 #define __dom0vp_add_memdesc(d, memmap_info, memdesc)	(-ENOSYS)
+#define dom0vp_get_memmap(domid, buffer)		(-ENOSYS)
 #endif
 
 extern volatile unsigned long *mpt_table;
diff -r 088bc049f889 xen/include/public/arch-ia64.h
--- a/xen/include/public/arch-ia64.h	Thu Oct 02 15:24:18 2008 +0900
+++ b/xen/include/public/arch-ia64.h	Thu Oct 02 15:25:22 2008 +0900
@@ -463,6 +463,11 @@
 /* unexpose the foreign domain's p2m table into privileged domain */
 #define IA64_DOM0VP_unexpose_foreign_p2m        13
 
+/* get memmap_info and memmap. It is possible to map the page directly
+   by foreign page mapping, but there is a race between writer.
+   This hypercall avoids such race. */
+#define IA64_DOM0VP_get_memmap          14
+
 // flags for page assignement to pseudo physical address space
 #define _ASSIGN_readonly                0
 #define ASSIGN_readonly                 (1UL << _ASSIGN_readonly)