[RFC V2 33/37] kvm, x86: enable record_steal_time for dmem

[yulei . kernel]

From: Yulei Zhang <yuleixzh...@tencent.com>

Adjust the kvm_map_gfn while using dmemfs to enable
record_steal_time when entering the guest.

Signed-off-by: Yulei Zhang <yuleixzh...@tencent.com>
---
 virt/kvm/kvm_main.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 2541a17..500b170 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -51,6 +51,7 @@
 #include <linux/io.h>
 #include <linux/lockdep.h>
 #include <linux/kthread.h>
+#include <linux/dmem.h>
 
 #include <asm/processor.h>
 #include <asm/ioctl.h>
@@ -2164,7 +2165,10 @@ static int __kvm_map_gfn(struct kvm_memslots *slots, 
gfn_t gfn,
                        hva = kmap(page);
 #ifdef CONFIG_HAS_IOMEM
        } else if (!atomic) {
-               hva = memremap(pfn_to_hpa(pfn), PAGE_SIZE, MEMREMAP_WB);
+               if (is_dmem_pfn(pfn))
+                       hva = __va(PFN_PHYS(pfn));
+               else
+                       hva = memremap(pfn_to_hpa(pfn), PAGE_SIZE, MEMREMAP_WB);
        } else {
                return -EINVAL;
 #endif
@@ -2214,9 +2218,10 @@ static void __kvm_unmap_gfn(struct kvm_memory_slot 
*memslot,
                        kunmap(map->page);
        }
 #ifdef CONFIG_HAS_IOMEM
-       else if (!atomic)
-               memunmap(map->hva);
-       else
+       else if (!atomic) {
+               if (!is_dmem_pfn(map->pfn))
+                       memunmap(map->hva);
+       } else
                WARN_ONCE(1, "Unexpected unmapping in atomic context");
 #endif
 
-- 
1.8.3.1