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-rw-r--r--migration/cpr-exec.c95
-rw-r--r--migration/cpr.c23
-rw-r--r--migration/migration.c10
-rw-r--r--migration/ram.c1
-rw-r--r--migration/trace-events1
-rw-r--r--migration/vmstate-types.c8
6 files changed, 135 insertions, 3 deletions
diff --git a/migration/cpr-exec.c b/migration/cpr-exec.c
index 81d84425e1..d57714bc5d 100644
--- a/migration/cpr-exec.c
+++ b/migration/cpr-exec.c
@@ -6,15 +6,21 @@
 
 #include "qemu/osdep.h"
 #include "qemu/cutils.h"
+#include "qemu/error-report.h"
 #include "qemu/memfd.h"
 #include "qapi/error.h"
+#include "qapi/type-helpers.h"
 #include "io/channel-file.h"
 #include "io/channel-socket.h"
+#include "block/block-global-state.h"
+#include "qemu/main-loop.h"
 #include "migration/cpr.h"
 #include "migration/qemu-file.h"
+#include "migration/migration.h"
 #include "migration/misc.h"
 #include "migration/vmstate.h"
 #include "system/runstate.h"
+#include "trace.h"
 
 #define CPR_EXEC_STATE_NAME "QEMU_CPR_EXEC_STATE"
 
@@ -97,3 +103,92 @@ QEMUFile *cpr_exec_input(Error **errp)
     lseek(mfd, 0, SEEK_SET);
     return qemu_file_new_fd_input(mfd, CPR_EXEC_STATE_NAME);
 }
+
+static bool preserve_fd(int fd)
+{
+    qemu_clear_cloexec(fd);
+    return true;
+}
+
+static bool unpreserve_fd(int fd)
+{
+    qemu_set_cloexec(fd);
+    return true;
+}
+
+static void cpr_exec_preserve_fds(void)
+{
+    cpr_walk_fd(preserve_fd);
+}
+
+void cpr_exec_unpreserve_fds(void)
+{
+    cpr_walk_fd(unpreserve_fd);
+}
+
+static void cpr_exec_cb(void *opaque)
+{
+    MigrationState *s = migrate_get_current();
+    char **argv = strv_from_str_list(s->parameters.cpr_exec_command);
+    Error *err = NULL;
+
+    /*
+     * Clear the close-on-exec flag for all preserved fd's.  We cannot do so
+     * earlier because they should not persist across miscellaneous fork and
+     * exec calls that are performed during normal operation.
+     */
+    cpr_exec_preserve_fds();
+
+    trace_cpr_exec();
+    execvp(argv[0], argv);
+
+    /*
+     * exec should only fail if argv[0] is bogus, or has a permissions problem,
+     * or the system is very short on resources.
+     */
+    g_strfreev(argv);
+    cpr_exec_unpreserve_fds();
+
+    error_setg_errno(&err, errno, "execvp %s failed", argv[0]);
+    error_report_err(error_copy(err));
+    migrate_set_state(&s->state, s->state, MIGRATION_STATUS_FAILED);
+    migrate_set_error(s, err);
+
+    /* Note, we can go from state COMPLETED to FAILED */
+    migration_call_notifiers(s, MIG_EVENT_PRECOPY_FAILED, NULL);
+
+    err = NULL;
+    if (!migration_block_activate(&err)) {
+        /* error was already reported */
+        error_free(err);
+        return;
+    }
+
+    if (runstate_is_live(s->vm_old_state)) {
+        vm_start();
+    }
+}
+
+static int cpr_exec_notifier(NotifierWithReturn *notifier, MigrationEvent *e,
+                             Error **errp)
+{
+    MigrationState *s = migrate_get_current();
+
+    if (e->type == MIG_EVENT_PRECOPY_DONE) {
+        QEMUBH *cpr_exec_bh = qemu_bh_new(cpr_exec_cb, NULL);
+        assert(s->state == MIGRATION_STATUS_COMPLETED);
+        qemu_bh_schedule(cpr_exec_bh);
+        qemu_notify_event();
+    } else if (e->type == MIG_EVENT_PRECOPY_FAILED) {
+        cpr_exec_unpersist_state();
+    }
+    return 0;
+}
+
+void cpr_exec_init(void)
+{
+    static NotifierWithReturn exec_notifier;
+
+    migration_add_notifier_mode(&exec_notifier, cpr_exec_notifier,
+                                MIG_MODE_CPR_EXEC);
+}
diff --git a/migration/cpr.c b/migration/cpr.c
index 6feda78f1b..22dbac7c72 100644
--- a/migration/cpr.c
+++ b/migration/cpr.c
@@ -6,6 +6,7 @@
  */
 
 #include "qemu/osdep.h"
+#include "qemu/error-report.h"
 #include "qapi/error.h"
 #include "qemu/error-report.h"
 #include "hw/vfio/vfio-device.h"
@@ -186,6 +187,8 @@ int cpr_state_save(MigrationChannel *channel, Error **errp)
     if (mode == MIG_MODE_CPR_TRANSFER) {
         g_assert(channel);
         f = cpr_transfer_output(channel, errp);
+    } else if (mode == MIG_MODE_CPR_EXEC) {
+        f = cpr_exec_output(errp);
     } else {
         return 0;
     }
@@ -202,6 +205,10 @@ int cpr_state_save(MigrationChannel *channel, Error **errp)
         return ret;
     }
 
+    if (migrate_mode() == MIG_MODE_CPR_EXEC) {
+        cpr_exec_persist_state(f);
+    }
+
     /*
      * Close the socket only partially so we can later detect when the other
      * end closes by getting a HUP event.
@@ -220,7 +227,13 @@ int cpr_state_load(MigrationChannel *channel, Error **errp)
     QEMUFile *f;
     MigMode mode = 0;
 
-    if (channel) {
+    if (cpr_exec_has_state()) {
+        mode = MIG_MODE_CPR_EXEC;
+        f = cpr_exec_input(errp);
+        if (channel) {
+            warn_report("ignoring cpr channel for migration mode cpr-exec");
+        }
+    } else if (channel) {
         mode = MIG_MODE_CPR_TRANSFER;
         cpr_set_incoming_mode(mode);
         f = cpr_transfer_input(channel, errp);
@@ -232,6 +245,7 @@ int cpr_state_load(MigrationChannel *channel, Error **errp)
     }
 
     trace_cpr_state_load(MigMode_str(mode));
+    cpr_set_incoming_mode(mode);
 
     v = qemu_get_be32(f);
     if (v != QEMU_CPR_FILE_MAGIC) {
@@ -252,6 +266,11 @@ int cpr_state_load(MigrationChannel *channel, Error **errp)
         return ret;
     }
 
+    if (migrate_mode() == MIG_MODE_CPR_EXEC) {
+        /* Set cloexec to prevent fd leaks from fork until the next cpr-exec */
+        cpr_exec_unpreserve_fds();
+    }
+
     /*
      * Let the caller decide when to close the socket (and generate a HUP event
      * for the sending side).
@@ -272,7 +291,7 @@ void cpr_state_close(void)
 bool cpr_incoming_needed(void *opaque)
 {
     MigMode mode = migrate_mode();
-    return mode == MIG_MODE_CPR_TRANSFER;
+    return mode == MIG_MODE_CPR_TRANSFER || mode == MIG_MODE_CPR_EXEC;
 }
 
 /*
diff --git a/migration/migration.c b/migration/migration.c
index a399735f02..a63b46bbef 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -333,6 +333,7 @@ void migration_object_init(void)
 
     ram_mig_init();
     dirty_bitmap_mig_init();
+    cpr_exec_init();
 
     /* Initialize cpu throttle timers */
     cpu_throttle_init();
@@ -1807,7 +1808,8 @@ bool migrate_mode_is_cpr(MigrationState *s)
 {
     MigMode mode = s->parameters.mode;
     return mode == MIG_MODE_CPR_REBOOT ||
-           mode == MIG_MODE_CPR_TRANSFER;
+           mode == MIG_MODE_CPR_TRANSFER ||
+           mode == MIG_MODE_CPR_EXEC;
 }
 
 int migrate_init(MigrationState *s, Error **errp)
@@ -2156,6 +2158,12 @@ static bool migrate_prepare(MigrationState *s, bool resume, Error **errp)
         return false;
     }
 
+    if (migrate_mode() == MIG_MODE_CPR_EXEC &&
+        !s->parameters.has_cpr_exec_command) {
+        error_setg(errp, "cpr-exec mode requires setting cpr-exec-command");
+        return false;
+    }
+
     if (migration_is_blocked(errp)) {
         return false;
     }
diff --git a/migration/ram.c b/migration/ram.c
index a8e8d2cc67..9aac89638a 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -228,6 +228,7 @@ bool migrate_ram_is_ignored(RAMBlock *block)
     MigMode mode = migrate_mode();
     return !qemu_ram_is_migratable(block) ||
            mode == MIG_MODE_CPR_TRANSFER ||
+           mode == MIG_MODE_CPR_EXEC ||
            (migrate_ignore_shared() && qemu_ram_is_shared(block)
                                     && qemu_ram_is_named_file(block));
 }
diff --git a/migration/trace-events b/migration/trace-events
index 706db97def..e8edd1fbba 100644
--- a/migration/trace-events
+++ b/migration/trace-events
@@ -354,6 +354,7 @@ cpr_state_save(const char *mode) "%s mode"
 cpr_state_load(const char *mode) "%s mode"
 cpr_transfer_input(const char *path) "%s"
 cpr_transfer_output(const char *path) "%s"
+cpr_exec(void) ""
 
 # block-dirty-bitmap.c
 send_bitmap_header_enter(void) ""
diff --git a/migration/vmstate-types.c b/migration/vmstate-types.c
index a1cd7a95fa..4b01dc19c2 100644
--- a/migration/vmstate-types.c
+++ b/migration/vmstate-types.c
@@ -322,6 +322,10 @@ static int get_fd(QEMUFile *f, void *pv, size_t size,
                   const VMStateField *field)
 {
     int32_t *v = pv;
+    if (migrate_mode() == MIG_MODE_CPR_EXEC) {
+        qemu_get_sbe32s(f, v);
+        return 0;
+    }
     *v = qemu_file_get_fd(f);
     return 0;
 }
@@ -330,6 +334,10 @@ static int put_fd(QEMUFile *f, void *pv, size_t size,
                   const VMStateField *field, JSONWriter *vmdesc)
 {
     int32_t *v = pv;
+    if (migrate_mode() == MIG_MODE_CPR_EXEC) {
+        qemu_put_sbe32s(f, v);
+        return 0;
+    }
     return qemu_file_put_fd(f, *v);
 }