introduce a new monitor command 'dump-guest-memory' to dump guest's memory

The command's usage:
   dump-guest-memory [-p] protocol [begin] [length]
The supported protocol can be file or fd:
1. file: the protocol starts with "file:", and the following string is
   the file's path.
2. fd: the protocol starts with "fd:", and the following string is the
   fd's name.

Note:
  1. If you want to use gdb to process the core, please specify -p option.
     The reason why the -p option is not default is:
       a. guest machine in a catastrophic state can have corrupted memory,
          which we cannot trust.
       b. The guest machine can be in read-mode even if paging is enabled.
          For example: the guest machine uses ACPI to sleep, and ACPI sleep
          state goes in real-mode.
  2. If you don't want to dump all guest's memory, please specify the start
     physical address and the length.

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>

1 files changed, 22 insertions, 0 deletions

diff --git a/hmp.c b/hmp.c
index bb0952e00b..42ced2a202 100644
--- a/hmp.c
+++ b/hmp.c
@@ -947,3 +947,25 @@ void hmp_device_del(Monitor *mon, const QDict *qdict)
     qmp_device_del(id, &err);
     hmp_handle_error(mon, &err);
 }
+
+void hmp_dump_guest_memory(Monitor *mon, const QDict *qdict)
+{
+    Error *errp = NULL;
+    int paging = qdict_get_try_bool(qdict, "paging", 0);
+    const char *file = qdict_get_str(qdict, "protocol");
+    bool has_begin = qdict_haskey(qdict, "begin");
+    bool has_length = qdict_haskey(qdict, "length");
+    int64_t begin = 0;
+    int64_t length = 0;
+
+    if (has_begin) {
+        begin = qdict_get_int(qdict, "begin");
+    }
+    if (has_length) {
+        length = qdict_get_int(qdict, "length");
+    }
+
+    qmp_dump_guest_memory(paging, file, has_begin, begin, has_length, length,
+                          &errp);
+    hmp_handle_error(mon, &errp);
+}