Modify all .log_global_start() handlers to take an Error** parameter
and return a bool. Adapt memory_global_dirty_log_start() to interrupt
on the first error the loop on handlers. In such case, a rollback is
performed to stop dirty logging on all listeners where it was
previously enabled.
Cc: Stefano Stabellini <sstabell...@kernel.org>
Cc: Anthony Perard <anthony.per...@citrix.com>
Cc: Paul Durrant <p...@xen.org>
Cc: "Michael S. Tsirkin" <m...@redhat.com>
Cc: Paolo Bonzini <pbonz...@redhat.com>
Cc: David Hildenbrand <da...@redhat.com>
Signed-off-by: Cédric Le Goater <c...@redhat.com>
---
Changes in v4:
- Dropped log_global_stop() and log_global_sync() changes
- Dropped MEMORY_LISTENER_CALL_LOG_GLOBAL
- Modified memory_global_dirty_log_start() to loop on the list of
listeners and handle errors directly.
- Introduced memory_global_dirty_log_rollback() to revert operations
previously done
Changes in v3:
- Fixed return value of vfio_listener_log_global_start() and
vfio_listener_log_global_stop(). Went unnoticed because not tested.
include/exec/memory.h | 5 ++++-
hw/i386/xen/xen-hvm.c | 3 ++-
hw/vfio/common.c | 4 +++-
hw/virtio/vhost.c | 3 ++-
system/memory.c | 43 +++++++++++++++++++++++++++++++++++++++++--
5 files changed, 52 insertions(+), 6 deletions(-)
diff --git a/include/exec/memory.h b/include/exec/memory.h
index
8626a355b310ed7b1a1db7978ba4b394032c2f15..5555567bc4c9fdb53e8f63487f1400980275687d
100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -998,8 +998,11 @@ struct MemoryListener {
* active at that time.
*
* @listener: The #MemoryListener.
+ * @errp: pointer to Error*, to store an error if it happens.
+ *
+ * Return: true on success, else false setting @errp with error.
*/
- void (*log_global_start)(MemoryListener *listener);
+ bool (*log_global_start)(MemoryListener *listener, Error **errp);
/**
* @log_global_stop:
diff --git a/hw/i386/xen/xen-hvm.c b/hw/i386/xen/xen-hvm.c
index
f42621e6742552035122ea58092c91c3458338ff..0608ca99f5166fd6379ee674442484e805eff9c0
100644
--- a/hw/i386/xen/xen-hvm.c
+++ b/hw/i386/xen/xen-hvm.c
@@ -446,11 +446,12 @@ static void xen_log_sync(MemoryListener *listener,
MemoryRegionSection *section)
int128_get64(section->size));
}
-static void xen_log_global_start(MemoryListener *listener)
+static bool xen_log_global_start(MemoryListener *listener, Error **errp)
{
if (xen_enabled()) {
xen_in_migration = true;
}
+ return true;
}
static void xen_log_global_stop(MemoryListener *listener)
diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index
ff88c3f31ca660b3c0a790601100fdc6116192a0..800ba0aeac84b8dcc83b042bb70c37b4bf78d3f4
100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -1075,7 +1075,8 @@ out:
return ret;
}
-static void vfio_listener_log_global_start(MemoryListener *listener)
+static bool vfio_listener_log_global_start(MemoryListener *listener,
+ Error **errp)
{
VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
listener);
@@ -1092,6 +1093,7 @@ static void vfio_listener_log_global_start(MemoryListener
*listener)
ret, strerror(-ret));
vfio_set_migration_error(ret);
}
+ return !ret;
}
static void vfio_listener_log_global_stop(MemoryListener *listener)
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index
2c9ac794680ea9b65eba6cc22e70cf141e90aa73..030b24db9270fc272024db3ff60a6cc449fba1ca
100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -1044,7 +1044,7 @@ check_dev_state:
return r;
}
-static void vhost_log_global_start(MemoryListener *listener)
+static bool vhost_log_global_start(MemoryListener *listener, Error **errp)
{
int r;
@@ -1052,6 +1052,7 @@ static void vhost_log_global_start(MemoryListener
*listener)
if (r < 0) {
abort();
}
+ return true;
}
static void vhost_log_global_stop(MemoryListener *listener)
diff --git a/system/memory.c b/system/memory.c
index
a229a79988fce2aa3cb77e3a130db4c694e8cd49..3600e716149407c10a1f6bf8f0a81c2611cf15ba
100644
--- a/system/memory.c
+++ b/system/memory.c
@@ -2914,9 +2914,27 @@ static unsigned int postponed_stop_flags;
static VMChangeStateEntry *vmstate_change;
static void memory_global_dirty_log_stop_postponed_run(void);
+/*
+ * Stop dirty logging on all listeners where it was previously enabled.
+ */
+static void memory_global_dirty_log_rollback(MemoryListener *listener,
+ unsigned int flags)
+{
+ global_dirty_tracking &= ~flags;
+ trace_global_dirty_changed(global_dirty_tracking);
+
+ while (listener) {
+ if (listener->log_global_stop) {
+ listener->log_global_stop(listener);
+ }
+ listener = QTAILQ_PREV(listener, link);
+ }
+}
+
void memory_global_dirty_log_start(unsigned int flags)
{
unsigned int old_flags;
+ Error *local_err = NULL;
assert(flags && !(flags & (~GLOBAL_DIRTY_MASK)));
@@ -2936,7 +2954,25 @@ void memory_global_dirty_log_start(unsigned int flags)
trace_global_dirty_changed(global_dirty_tracking);
if (!old_flags) {
- MEMORY_LISTENER_CALL_GLOBAL(log_global_start, Forward);
+ MemoryListener *listener;
+ bool ret = true;
+
+ QTAILQ_FOREACH(listener, &memory_listeners, link) {
+ if (listener->log_global_start) {
+ ret = listener->log_global_start(listener, &local_err);
+ if (!ret) {
+ break;
+ }
+ }
+ }
+
+ if (!ret) {
+ memory_global_dirty_log_rollback(QTAILQ_PREV(listener, link),
+ flags);
+ error_report_err(local_err);
+ return;
+ }
+
memory_region_transaction_begin();
memory_region_update_pending = true;
memory_region_transaction_commit();
@@ -3009,13 +3045,16 @@ static void listener_add_address_space(MemoryListener
*listener,
{
FlatView *view;
FlatRange *fr;
+ Error *local_err = NULL;
if (listener->begin) {
listener->begin(listener);
}
if (global_dirty_tracking) {
if (listener->log_global_start) {
- listener->log_global_start(listener);
+ if (!listener->log_global_start(listener, &local_err)) {
+ error_report_err(local_err);
+ }
}
}
--
2.44.0
