From df524f377362a56e8f6b0a731d9ad763a8f197a4 Mon Sep 17 00:00:00 2001
From: "iap10@labyrinth.cl.cam.ac.uk" <iap10@labyrinth.cl.cam.ac.uk>
Date: Fri, 10 Sep 2004 17:40:57 +0000
Subject: [PATCH] bitkeeper revision 1.1159.75.1
 (4141e7297AE7URpA2fz0RRbAQySy8w)

Migration fix for immutable back pointers.
---
 tools/libxc/xc_linux_restore.c |  7 ++++++-
 xen/arch/x86/memory.c          | 31 +++++++++++++------------------
 2 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/tools/libxc/xc_linux_restore.c b/tools/libxc/xc_linux_restore.c
index fe7522e1ed..977a60f841 100644
--- a/tools/libxc/xc_linux_restore.c
+++ b/tools/libxc/xc_linux_restore.c
@@ -484,7 +484,12 @@ int xc_linux_restore(int xc_handle, XcIOContext *ioctxt)
                 goto out;
             }
         }
-        else if ( pfn_type[i] == (L2TAB|LPINTAB) )
+    }
+
+    /* must pin all L1's before L2's (need consistent va back ptr) */
+    for ( i = 0; i < nr_pfns; i++ )
+    {
+        if ( pfn_type[i] == (L2TAB|LPINTAB) )
         {
             if ( add_mmu_update(xc_handle, mmu,
                                 (pfn_to_mfn_table[i]<<PAGE_SHIFT) | 
diff --git a/xen/arch/x86/memory.c b/xen/arch/x86/memory.c
index 640181a6cc..acc5d37cd7 100644
--- a/xen/arch/x86/memory.c
+++ b/xen/arch/x86/memory.c
@@ -1455,8 +1455,9 @@ int do_mmu_update(mmu_update_t *ureqs, int count, int *success_count)
              * If in log-dirty mode, mark the corresponding pseudo-physical
              * page as dirty.
              */
-            if ( unlikely(d->mm.shadow_mode == SHM_logdirty) )
-                mark_dirty(&d->mm, pfn);
+            if ( unlikely(d->mm.shadow_mode == SHM_logdirty) && 
+		 mark_dirty(&d->mm, pfn) )
+		d->mm.shadow_dirty_block_count++;
 
             put_page(&frame_table[pfn]);
             break;
@@ -1739,7 +1740,7 @@ void ptwr_flush_inactive(void)
     }
     unmap_domain_mem(pl1e);
 
-    /* make pt page writable */
+    /* make pt page write protected */
     if (__get_user(pte, writable_pte)) {
         MEM_LOG("ptwr: Could not read pte at %p\n", writable_pte);
         domain_crash();
@@ -1816,21 +1817,10 @@ int ptwr_do_page_fault(unsigned long addr)
             }
             else
             {
-                l2_pgentry_t nl2e;
-
                 if ( ptwr_info[cpu].disconnected_pteidx >= 0 )
                     ptwr_reconnect_disconnected();
-                PTWR_PRINTK(PP_A, ("[A]    pl2e %p l2e %08lx pfn %08lx "
-                                   "taf %08x/%08x\n", pl2e,
-                                   l2_pgentry_val(*pl2e),
-                                   l1_pgentry_val(linear_pg_table
-                                                  [(unsigned long)pl2e >>
-                                                   PAGE_SHIFT]) >> PAGE_SHIFT,
-                                   frame_table[pfn].u.inuse.type_info,
-                                   frame_table[pfn].count_info));
-                /* disconnect l1 page */
-                nl2e = mk_l2_pgentry((l2_pgentry_val(*pl2e) & ~_PAGE_PRESENT));
-                update_l2e(pl2e, *pl2e, nl2e);
+
+		/* No need to actually disconnect L1 anymore in v2 wr_pt  */
 
                 ptwr_info[cpu].disconnected_pteidx =
                     (page->u.inuse.type_info & PGT_va_mask) >> PGT_va_shift;
@@ -1841,11 +1831,16 @@ int ptwr_do_page_fault(unsigned long addr)
                                    frame_table[pfn].count_info));
                 ptwr_info[cpu].disconnected_l1va = addr;
                 ptwr_info[cpu].disconnected_pl1e =
-                    map_domain_mem(l2_pgentry_to_pagenr(nl2e) << PAGE_SHIFT);
+                    map_domain_mem( l2_pgentry_to_pagenr(*pl2e)<<PAGE_SHIFT );
+
+		/* XXX we could use the linear page table here... */	      
+		ASSERT( ((page->u.inuse.type_info & PGT_va_mask) >> 
+			 PGT_va_shift) < (PAGE_OFFSET >> L2_PAGETABLE_SHIFT)); 
+
                 memcpy(&ptwr_info[cpu].disconnected_page[0],
                        ptwr_info[cpu].disconnected_pl1e,
                        ENTRIES_PER_L1_PAGETABLE * sizeof(l1_pgentry_t));
-
+				  
                 /* make pt page writable */
                 ptwr_info[cpu].disconnected_pte = pte;
                 pte = (virt_to_phys(ptwr_info[cpu].disconnected_page) &
-- 
2.30.2