VM state change handler is called on change in VM's state. Based on
VM state, VFIO device state should be changed.
Added read/write helper functions for migration region.
Added function to set device_state.
Signed-off-by: Kirti Wankhede
Reviewed-by: Neo Jia
Reviewed-by: Dr. David Alan Gilbert
---
hw/vfio/migration.c | 156 ++
hw/vfio/trace-events | 2 +
include/hw/vfio/vfio-common.h | 4 ++
3 files changed, 162 insertions(+)
diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
index bbe6e0b7a6cc..9b6949439f8e 100644
--- a/hw/vfio/migration.c
+++ b/hw/vfio/migration.c
@@ -10,6 +10,7 @@
#include "qemu/osdep.h"
#include
+#include "sysemu/runstate.h"
#include "hw/vfio/vfio-common.h"
#include "cpu.h"
#include "migration/migration.h"
@@ -22,6 +23,157 @@
#include "exec/ram_addr.h"
#include "pci.h"
#include "trace.h"
+#include "hw/hw.h"
+
+static inline int vfio_mig_access(VFIODevice *vbasedev, void *val, int count,
+ off_t off, bool iswrite)
+{
+int ret;
+
+ret = iswrite ? pwrite(vbasedev->fd, val, count, off) :
+pread(vbasedev->fd, val, count, off);
+if (ret < count) {
+error_report("vfio_mig_%s %d byte %s: failed at offset 0x%lx, err: %s",
+ iswrite ? "write" : "read", count,
+ vbasedev->name, off, strerror(errno));
+return (ret < 0) ? ret : -EINVAL;
+}
+return 0;
+}
+
+static int vfio_mig_rw(VFIODevice *vbasedev, __u8 *buf, size_t count,
+ off_t off, bool iswrite)
+{
+int ret, done = 0;
+__u8 *tbuf = buf;
+
+while (count) {
+int bytes = 0;
+
+if (count >= 8 && !(off % 8)) {
+bytes = 8;
+} else if (count >= 4 && !(off % 4)) {
+bytes = 4;
+} else if (count >= 2 && !(off % 2)) {
+bytes = 2;
+} else {
+bytes = 1;
+}
+
+ret = vfio_mig_access(vbasedev, tbuf, bytes, off, iswrite);
+if (ret) {
+return ret;
+}
+
+count -= bytes;
+done += bytes;
+off += bytes;
+tbuf += bytes;
+}
+return done;
+}
+
+#define vfio_mig_read(f, v, c, o) vfio_mig_rw(f, (__u8 *)v, c, o, false)
+#define vfio_mig_write(f, v, c, o) vfio_mig_rw(f, (__u8 *)v, c, o, true)
+
+#define VFIO_MIG_STRUCT_OFFSET(f) \
+ offsetof(struct vfio_device_migration_info, f)
+/*
+ * Change the device_state register for device @vbasedev. Bits set in @mask
+ * are preserved, bits set in @value are set, and bits not set in either @mask
+ * or @value are cleared in device_state. If the register cannot be accessed,
+ * the resulting state would be invalid, or the device enters an error state,
+ * an error is returned.
+ */
+
+static int vfio_migration_set_state(VFIODevice *vbasedev, uint32_t mask,
+uint32_t value)
+{
+VFIOMigration *migration = vbasedev->migration;
+VFIORegion *region = >region;
+off_t dev_state_off = region->fd_offset +
+ VFIO_MIG_STRUCT_OFFSET(device_state);
+uint32_t device_state;
+int ret;
+
+ret = vfio_mig_read(vbasedev, _state, sizeof(device_state),
+dev_state_off);
+if (ret < 0) {
+return ret;
+}
+
+device_state = (device_state & mask) | value;
+
+if (!VFIO_DEVICE_STATE_VALID(device_state)) {
+return -EINVAL;
+}
+
+ret = vfio_mig_write(vbasedev, _state, sizeof(device_state),
+ dev_state_off);
+if (ret < 0) {
+int rret;
+
+rret = vfio_mig_read(vbasedev, _state, sizeof(device_state),
+ dev_state_off);
+
+if ((rret < 0) || (VFIO_DEVICE_STATE_IS_ERROR(device_state))) {
+hw_error("%s: Device in error state 0x%x", vbasedev->name,
+ device_state);
+return rret ? rret : -EIO;
+}
+return ret;
+}
+
+migration->device_state = device_state;
+trace_vfio_migration_set_state(vbasedev->name, device_state);
+return 0;
+}
+
+static void vfio_vmstate_change(void *opaque, int running, RunState state)
+{
+VFIODevice *vbasedev = opaque;
+VFIOMigration *migration = vbasedev->migration;
+uint32_t value, mask;
+int ret;
+
+if ((vbasedev->migration->vm_running == running)) {
+return;
+}
+
+if (running) {
+/*
+ * Here device state can have one of _SAVING, _RESUMING or _STOP bit.
+ * Transition from _SAVING to _RUNNING can happen if there is migration
+ * failure, in that case clear _SAVING bit.
+ * Transition from _RESUMING to _RUNNING occurs during resuming
+ * phase, in that case clear _RESUMING bit.
+ * In both the above cases, set _RUNNING bit.
+ */
+mask = ~VFIO_DEVICE_STATE_MASK;
+value =
