[PATCH 2/2] vhost-vdpa: add uAPI for logging

[Jiang Dongxu]

From: jiangdongxu <jiangdongxu1@xxxxxxxxxx>

These new ioctl add support for setting bitmaps config,
like base address and buffer size from userspace.

When setup migration, VMM will call VHOST_SET_LOG_BASE and
VHOST_SET_LOG_SIZE to set address and size of buffer used
for storing bitmaps.

Then VMM start live migration, VMM will enable logging
vhost device by set feature VHOST_F_LOG_ALL.

And during live migration iterate, VMM get dirty page info
from vhost device by calling VHOST_LOG_SYNC.

Signed-off-by: jiangdongxu <jiangdongxu1@xxxxxxxxxx>
---
 drivers/vhost/vdpa.c       | 49 ++++++++++++++++++++++++++++++++++++++
 include/uapi/linux/vhost.h |  4 ++++
 2 files changed, 53 insertions(+)

diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index b43e8680eee8..75e17d9b136b 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -556,6 +556,47 @@ static long vhost_vdpa_resume(struct vhost_vdpa *v)
 	return ops->resume(vdpa);
 }
 
+static long vhost_vdpa_set_log_base(struct vhost_vdpa *v, u64 __user *argp)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+	u64 log;
+
+	if (!ops->set_log_base)
+		return -EOPNOTSUPP;
+
+	if (copy_from_user(&log, argp, sizeof(uint64_t)))
+		return -EFAULT;
+
+	return ops->set_log_base(vdpa, log);
+}
+
+static long vhost_vdpa_set_log_size(struct vhost_vdpa *v, u64 __user *sizep)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+	u64 log_size;
+
+	if (!ops->set_log_size)
+		return -EOPNOTSUPP;
+
+	if (copy_from_user(&log_size, sizep, sizeof(log_size)))
+		return -EFAULT;
+
+	return ops->set_log_size(vdpa, log_size);
+}
+
+static long vhost_vdpa_log_sync(struct vhost_vdpa *v)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+
+	if (!ops->log_sync)
+		return -EOPNOTSUPP;
+
+	return ops->log_sync(vdpa);
+}
+
 static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
 				   void __user *argp)
 {
@@ -729,6 +770,14 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep,
 			r = -EFAULT;
 		break;
 	case VHOST_SET_LOG_BASE:
+		r = vhost_vdpa_set_log_base(v, argp);
+		break;
+	case VHOST_SET_LOG_SIZE:
+		r = vhost_vdpa_set_log_size(v, argp);
+		break;
+	case VHOST_LOG_SYNC:
+		r = vhost_vdpa_log_sync(v);
+		break;
 	case VHOST_SET_LOG_FD:
 		r = -ENOIOCTLCMD;
 		break;
diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h
index f5c48b61ab62..ce9d187432d1 100644
--- a/include/uapi/linux/vhost.h
+++ b/include/uapi/linux/vhost.h
@@ -43,6 +43,10 @@
  * The bit is set using an atomic 32 bit operation. */
 /* Set base address for logging. */
 #define VHOST_SET_LOG_BASE _IOW(VHOST_VIRTIO, 0x04, __u64)
+/* Set buffer size for logging */
+#define VHOST_SET_LOG_SIZE _IOW(VHOST_VIRTIO, 0x05, __u64)
+/* Synchronize logging buffer from kernel space to user space */
+#define VHOST_LOG_SYNC _IO(VHOST_VIRTIO, 0x06)
 /* Specify an eventfd file descriptor to signal on log write. */
 #define VHOST_SET_LOG_FD _IOW(VHOST_VIRTIO, 0x07, int)
 /* By default, a device gets one vhost_worker that its virtqueues share. This
-- 
2.27.0