[RFC 11/43] PKRAM: pass the preserved pages pagetable to the next kernel

[Anthony Yznaga]

Add a pointer to the pagetable to the pkram_super_block page.

Signed-off-by: Anthony Yznaga <anthony.yzn...@oracle.com>
---
 mm/pkram.c | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/mm/pkram.c b/mm/pkram.c
index 5a7b8f61a55d..54b2779d0813 100644
--- a/mm/pkram.c
+++ b/mm/pkram.c
@@ -94,6 +94,7 @@ struct pkram_node {
  */
 struct pkram_super_block {
        __u64   node_pfn;               /* first element of the node list */
+       __u64   pgd_pfn;
 };
 
 static unsigned long pkram_sb_pfn __initdata;
@@ -769,15 +770,20 @@ static void __pkram_reboot(void)
        struct page *page;
        struct pkram_node *node;
        unsigned long node_pfn = 0;
-
-       list_for_each_entry_reverse(page, &pkram_nodes, lru) {
-               node = page_address(page);
-               if (WARN_ON(node->flags & PKRAM_ACCMODE_MASK))
-                       continue;
-               node->node_pfn = node_pfn;
-               node_pfn = page_to_pfn(page);
+       unsigned long pgd_pfn = 0;
+
+       if (pkram_pgd) {
+               list_for_each_entry_reverse(page, &pkram_nodes, lru) {
+                       node = page_address(page);
+                       if (WARN_ON(node->flags & PKRAM_ACCMODE_MASK))
+                               continue;
+                       node->node_pfn = node_pfn;
+                       node_pfn = page_to_pfn(page);
+               }
+               pgd_pfn = page_to_pfn(virt_to_page(pkram_pgd));
        }
        pkram_sb->node_pfn = node_pfn;
+       pkram_sb->pgd_pfn = pgd_pfn;
 }
 
 static int pkram_reboot(struct notifier_block *notifier,
-- 
2.13.3