Re: [RFC PATCH 15/19] kvm: handle KVM_EXIT_MEMORY_FAULT

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 8/3/2023 6:25 AM, Isaku Yamahata wrote:
On Mon, Jul 31, 2023 at 12:21:57PM -0400,
Xiaoyao Li <xiaoyao.li@xxxxxxxxx> wrote:

From: Chao Peng <chao.p.peng@xxxxxxxxxxxxxxx>

Currently only KVM_MEMORY_EXIT_FLAG_PRIVATE in flags is valid when
KVM_EXIT_MEMORY_FAULT happens. It indicates userspace needs to do
the memory conversion on the RAMBlock to turn the memory into desired
attribute, i.e., private/shared.

Note, KVM_EXIT_MEMORY_FAULT makes sense only when the RAMBlock has
gmem memory backend.

Signed-off-by: Chao Peng <chao.p.peng@xxxxxxxxxxxxxxx>
Signed-off-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>
---
  accel/kvm/kvm-all.c | 52 +++++++++++++++++++++++++++++++++++++++++++++
  1 file changed, 52 insertions(+)

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index f9b5050b8885..72d50b923bf2 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -3040,6 +3040,48 @@ static void kvm_eat_signals(CPUState *cpu)
      } while (sigismember(&chkset, SIG_IPI));
  }
+static int kvm_convert_memory(hwaddr start, hwaddr size, bool to_private)
+{
+    MemoryRegionSection section;
+    void *addr;
+    RAMBlock *rb;
+    ram_addr_t offset;
+    int ret = -1;
+
+    section = memory_region_find(get_system_memory(), start, size);
+    if (!section.mr) {
+        return ret;
+    }
+
+    if (memory_region_can_be_private(section.mr)) {
+        if (to_private) {
+            ret = kvm_set_memory_attributes_private(start, size);
+        } else {
+            ret = kvm_set_memory_attributes_shared(start, size);
+        }
+
+        if (ret) {
+            return ret;
+        }
+
+        addr = memory_region_get_ram_ptr(section.mr) +
+               section.offset_within_region;
+        rb = qemu_ram_block_from_host(addr, false, &offset);

Here we have already section. section.mr->ram_block.  We don't have to
scan the existing RAMBlocks.

But we don't have the @offset, do we?

Except that, looks good to me.
Reviewed-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>




[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]

  Powered by Linux