x86: reserve highmem pages via reserve_early

This patch makes early reserved highmem pages become reserved
pages. This can be used for highmem pages allocated by bootloader such
as EFI memory map, linked list of setup_data, etc.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: andi@firstfloor.org
Cc: mingo@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

2 files changed, 13 insertions, 1 deletions

diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index ac5e9ebf70e..a706e9057ba 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -612,6 +612,17 @@ void __init free_early(u64 start, u64 end)
         early_res[j - 1].end = 0;
 }
 
+int __init page_is_reserved_early(unsigned long pagenr)
+{
+        u64 start = (u64)pagenr << PAGE_SHIFT;
+        int i;
+        struct early_res *r;
+
+        i = find_overlapped_early(start, start + PAGE_SIZE);
+        r = &early_res[i];
+        return (i < MAX_EARLY_RES && r->end);
+}
+
 void __init early_res_to_bootmem(u64 start, u64 end)
 {
         int i;
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index ec30d10154b..0e7bb5e8167 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -289,7 +289,8 @@ static void __init permanent_kmaps_init(pgd_t *pgd_base)
 
 void __init add_one_highpage_init(struct page *page, int pfn, int bad_ppro)
 {
-        if (page_is_ram(pfn) && !(bad_ppro && page_kills_ppro(pfn))) {
+        if (page_is_ram(pfn) && !(bad_ppro && page_kills_ppro(pfn)) &&
+            !page_is_reserved_early(pfn)) {
                 ClearPageReserved(page);
                 init_page_count(page);
                 __free_page(page);