Commit f6d955d8 authored by Eli Cohen's avatar Eli Cohen Committed by Michael S. Tsirkin
Browse files

vdpa: Avoid taking cf_mutex lock on get status 



Avoid the wrapper holding cf_mutex since it is not protecting anything.
To avoid confusion and unnecessary overhead incurred by it, remove.

Fixes: f489f27bc0ab ("vdpa: Sync calls set/get config/status with cf_mutex")
Signed-off-by: default avatarEli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20220111183400.38418-2-elic@nvidia.com


Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: default avatarSi-Wei <Liu&lt;si-wei.liu@oracle.com>
Acked-by: default avatarJason Wang <jasowang@redhat.com>
parent b2ce6197

drivers/vdpa/vdpa.c

+0 −11
Original line number Diff line number Diff line
@@ -21,17 +21,6 @@ static LIST_HEAD(mdev_head); 
static DEFINE_MUTEX(vdpa_dev_mutex);

static DEFINE_IDA(vdpa_index_ida);



u8 vdpa_get_status(struct vdpa_device *vdev)

{

	u8 status;



	mutex_lock(&vdev->cf_mutex);

	status = vdev->config->get_status(vdev);

	mutex_unlock(&vdev->cf_mutex);

	return status;

}

EXPORT_SYMBOL(vdpa_get_status);



void vdpa_set_status(struct vdpa_device *vdev, u8 status)

{

	mutex_lock(&vdev->cf_mutex);

drivers/vhost/vdpa.c

+3 −2
Original line number Diff line number Diff line
@@ -142,9 +142,10 @@ static long vhost_vdpa_get_device_id(struct vhost_vdpa *v, u8 __user *argp) 
static long vhost_vdpa_get_status(struct vhost_vdpa *v, u8 __user *statusp)

{

	struct vdpa_device *vdpa = v->vdpa;

	const struct vdpa_config_ops *ops = vdpa->config;

	u8 status;



	status = vdpa_get_status(vdpa);

	status = ops->get_status(vdpa);



	if (copy_to_user(statusp, &status, sizeof(status)))

		return -EFAULT;
@@ -163,7 +164,7 @@ static long vhost_vdpa_set_status(struct vhost_vdpa *v, u8 __user *statusp) 
	if (copy_from_user(&status, statusp, sizeof(status)))

		return -EFAULT;



	status_old = vdpa_get_status(vdpa);

	status_old = ops->get_status(vdpa);



	/*

	 * Userspace shouldn't remove status bits unless reset the

include/linux/vdpa.h

+0 −1
Original line number Diff line number Diff line
@@ -421,7 +421,6 @@ void vdpa_get_config(struct vdpa_device *vdev, unsigned int offset, 
		     void *buf, unsigned int len);

void vdpa_set_config(struct vdpa_device *dev, unsigned int offset,

		     const void *buf, unsigned int length);

u8 vdpa_get_status(struct vdpa_device *vdev);

void vdpa_set_status(struct vdpa_device *vdev, u8 status);



/**