Commit b5b268cb authored by Alex Williamson's avatar Alex Williamson Committed by Alex Williamson
Browse files

vfio/virtio: Use guard() for migf->lock where applicable 



Convert migf->lock acquisitions in virtiovf_disable_fd() and
virtiovf_save_read() to use guard().  In virtiovf_save_read() this
eliminates the out_unlock label and multiple goto paths by allowing
direct returns, and removes the need for the done variable to double
as an error carrier.

Assisted-by: Claude:claude-opus-4-6
Signed-off-by: default avatarAlex Williamson <alex.williamson@nvidia.com>
Reviewed-by: default avatarYishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20260414200625.3601509-4-alex.williamson@nvidia.com


Signed-off-by: default avatarAlex Williamson <alex@shazbot.org>
parent 61fcb51f

drivers/vfio/pci/virtio/migrate.c

+14 −26
Original line number Diff line number Diff line
@@ -224,10 +224,9 @@ static void virtiovf_clean_migf_resources(struct virtiovf_migration_file *migf) 


static void virtiovf_disable_fd(struct virtiovf_migration_file *migf)

{

	mutex_lock(&migf->lock);

	guard(mutex)(&migf->lock);

	migf->state = VIRTIOVF_MIGF_STATE_ERROR;

	migf->filp->f_pos = 0;

	mutex_unlock(&migf->lock);

}



static void virtiovf_disable_fds(struct virtiovf_pci_core_device *virtvdev)
@@ -385,11 +384,10 @@ static ssize_t virtiovf_save_read(struct file *filp, char __user *buf, size_t le 
		return -ESPIPE;

	pos = &filp->f_pos;



	mutex_lock(&migf->lock);

	if (migf->state == VIRTIOVF_MIGF_STATE_ERROR) {

		done = -ENODEV;

		goto out_unlock;

	}

	guard(mutex)(&migf->lock);



	if (migf->state == VIRTIOVF_MIGF_STATE_ERROR)

		return -ENODEV;



	while (len) {

		ssize_t count;
@@ -398,34 +396,24 @@ static ssize_t virtiovf_save_read(struct file *filp, char __user *buf, size_t le 
		if (first_loop_call) {

			first_loop_call = false;

			/* Temporary end of file as part of PRE_COPY */

			if (end_of_data && migf->state == VIRTIOVF_MIGF_STATE_PRECOPY) {

				done = -ENOMSG;

				goto out_unlock;

			}

			if (end_of_data && migf->state != VIRTIOVF_MIGF_STATE_COMPLETE) {

				done = -EINVAL;

				goto out_unlock;

			}

			if (end_of_data && migf->state == VIRTIOVF_MIGF_STATE_PRECOPY)

				return -ENOMSG;

			if (end_of_data && migf->state != VIRTIOVF_MIGF_STATE_COMPLETE)

				return -EINVAL;

		}



		if (end_of_data)

			goto out_unlock;

			return done;



		if (!vhca_buf) {

			done = -EINVAL;

			goto out_unlock;

		}

		if (!vhca_buf)

			return -EINVAL;



		count = virtiovf_buf_read(vhca_buf, &buf, &len, pos);

		if (count < 0) {

			done = count;

			goto out_unlock;

		}

		if (count < 0)

			return count;

		done += count;

	}



out_unlock:

	mutex_unlock(&migf->lock);

	return done;

}