[Qemu-devel] [PATCH v4 04/11] dump-guest-memory: add dump_in_progress() helper function

[Peter Xu <peterx@redhat.com>]

For now, it has no effect. It will be used in dump detach support.

Signed-off-by: Peter Xu <peterx@redhat.com>
---
 dump.c                | 13 +++++++++++++
 include/qemu-common.h |  4 ++++
 qmp.c                 | 14 ++++++++++++++
 3 files changed, 31 insertions(+)

diff --git a/dump.c b/dump.c
index f5f3c59..3cf75db 100644
--- a/dump.c
+++ b/dump.c
@@ -1426,6 +1426,12 @@ static void dump_state_prepare(DumpState *s)
     *s = (DumpState) { .status = DUMP_STATUS_ACTIVE };
 }
 
+bool dump_in_progress(void)
+{
+    DumpState *state = &dump_state_global;
+    return (state->status == DUMP_STATUS_ACTIVE);
+}
+
 static void dump_init(DumpState *s, int fd, bool has_format,
                       DumpGuestMemoryFormat format, bool paging, bool has_filter,
                       int64_t begin, int64_t length, Error **errp)
@@ -1599,6 +1605,13 @@ void qmp_dump_guest_memory(bool paging, const char *file,
     DumpState *s;
     Error *local_err = NULL;
 
+    /* if there is a dump in background, we should wait until the dump
+     * finished */
+    if (dump_in_progress()) {
+        error_setg(errp, "There is a dump in process, please wait.");
+        return;
+    }
+
     /*
      * kdump-compressed format need the whole memory dumped, so paging or
      * filter is not supported here.
diff --git a/include/qemu-common.h b/include/qemu-common.h
index 405364f..7b74961 100644
--- a/include/qemu-common.h
+++ b/include/qemu-common.h
@@ -501,4 +501,8 @@ int parse_debug_env(const char *name, int max, int initial);
 const char *qemu_ether_ntoa(const MACAddr *mac);
 void page_size_init(void);
 
+/* returns non-zero if dump is in progress, otherwise zero is
+ * returned. */
+bool dump_in_progress(void);
+
 #endif
diff --git a/qmp.c b/qmp.c
index 0a1fa19..055586d 100644
--- a/qmp.c
+++ b/qmp.c
@@ -102,6 +102,13 @@ void qmp_quit(Error **errp)
 
 void qmp_stop(Error **errp)
 {
+    /* if there is a dump in background, we should wait until the dump
+     * finished */
+    if (dump_in_progress()) {
+        error_setg(errp, "There is a dump in process, please wait.");
+        return;
+    }
+
     if (runstate_check(RUN_STATE_INMIGRATE)) {
         autostart = 0;
     } else {
@@ -174,6 +181,13 @@ void qmp_cont(Error **errp)
     BlockBackend *blk;
     BlockDriverState *bs;
 
+    /* if there is a dump in background, we should wait until the dump
+     * finished */
+    if (dump_in_progress()) {
+        error_setg(errp, "There is a dump in process, please wait.");
+        return;
+    }
+
     if (runstate_needs_reset()) {
         error_setg(errp, "Resetting the Virtual Machine is required");
         return;
-- 
2.4.3