[PATCH V3 vfio 5/9] virtio-pci: Initialize the supported admin commands

[Yishai Hadas <yishaih@xxxxxxxxxx>]

Initialize the supported admin commands upon activating the admin queue.

The supported commands are saved as part of the admin queue context.

Next patches in this series will expose APIs to use them.

Signed-off-by: Yishai Hadas <yishaih@xxxxxxxxxx>
---
 drivers/virtio/virtio_pci_common.h |  1 +
 drivers/virtio/virtio_pci_modern.c | 48 ++++++++++++++++++++++++++++--
 2 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/drivers/virtio/virtio_pci_common.h b/drivers/virtio/virtio_pci_common.h
index a50a58014c9f..2e3ae417519d 100644
--- a/drivers/virtio/virtio_pci_common.h
+++ b/drivers/virtio/virtio_pci_common.h
@@ -47,6 +47,7 @@ struct virtio_pci_admin_vq {
 	struct virtio_pci_vq_info info;
 	/* serializing admin commands execution and virtqueue deletion */
 	struct mutex cmd_lock;
+	u64 supported_cmds;
 	/* Name of the admin queue: avq.$vq_index. */
 	char name[10];
 	u16 vq_index;
diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c
index 18366a82408c..951014dbb086 100644
--- a/drivers/virtio/virtio_pci_modern.c
+++ b/drivers/virtio/virtio_pci_modern.c
@@ -39,6 +39,7 @@ static bool vp_is_avq(struct virtio_device *vdev, unsigned int index)
 }
 
 static int virtqueue_exec_admin_cmd(struct virtio_pci_admin_vq *admin_vq,
+				    u16 opcode,
 				    struct scatterlist **sgs,
 				    unsigned int out_num,
 				    unsigned int in_num,
@@ -51,6 +52,11 @@ static int virtqueue_exec_admin_cmd(struct virtio_pci_admin_vq *admin_vq,
 	if (!vq)
 		return -EIO;
 
+	if (opcode != VIRTIO_ADMIN_CMD_LIST_QUERY &&
+	    opcode != VIRTIO_ADMIN_CMD_LIST_USE &&
+	    !((1ULL << opcode) & admin_vq->supported_cmds))
+		return -EOPNOTSUPP;
+
 	ret = virtqueue_add_sgs(vq, sgs, out_num, in_num, data, GFP_KERNEL);
 	if (ret < 0)
 		return -EIO;
@@ -117,8 +123,9 @@ static int vp_modern_admin_cmd_exec(struct virtio_device *vdev,
 	}
 
 	mutex_lock(&vp_dev->admin_vq.cmd_lock);
-	ret = virtqueue_exec_admin_cmd(&vp_dev->admin_vq, sgs,
-				       out_num, in_num, sgs);
+	ret = virtqueue_exec_admin_cmd(&vp_dev->admin_vq,
+				       le16_to_cpu(cmd->opcode),
+				       sgs, out_num, in_num, sgs);
 	mutex_unlock(&vp_dev->admin_vq.cmd_lock);
 
 	if (ret) {
@@ -142,6 +149,42 @@ static int vp_modern_admin_cmd_exec(struct virtio_device *vdev,
 	return ret;
 }
 
+static void virtio_pci_admin_cmd_list_init(struct virtio_device *virtio_dev)
+{
+	struct virtio_pci_device *vp_dev = to_vp_device(virtio_dev);
+	struct virtio_admin_cmd cmd = {};
+	struct scatterlist result_sg;
+	struct scatterlist data_sg;
+	__le64 *data;
+	int ret;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return;
+
+	sg_init_one(&result_sg, data, sizeof(*data));
+	cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_LIST_QUERY);
+	cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV);
+	cmd.result_sg = &result_sg;
+
+	ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd);
+	if (ret)
+		goto end;
+
+	sg_init_one(&data_sg, data, sizeof(*data));
+	cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_LIST_USE);
+	cmd.data_sg = &data_sg;
+	cmd.result_sg = NULL;
+
+	ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd);
+	if (ret)
+		goto end;
+
+	vp_dev->admin_vq.supported_cmds = le64_to_cpu(*data);
+end:
+	kfree(data);
+}
+
 static void vp_modern_avq_activate(struct virtio_device *vdev)
 {
 	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
@@ -151,6 +194,7 @@ static void vp_modern_avq_activate(struct virtio_device *vdev)
 		return;
 
 	__virtqueue_unbreak(admin_vq->info.vq);
+	virtio_pci_admin_cmd_list_init(vdev);
 }
 
 static void vp_modern_avq_deactivate(struct virtio_device *vdev)
-- 
2.27.0