Re: [PATCH v13 11/24] gunyah: vm_mgr: Add ioctls to support basic non-proxy VM boot

[Alex Elder]

On 5/9/23 3:47 PM, Elliot Berman wrote:
> Add remaining ioctls to support non-proxy VM boot:
>
>   - Gunyah Resource Manager uses the VM's devicetree to configure the
>     virtual machine. The location of the devicetree in the guest's
>     virtual memory can be declared via the SET_DTB_CONFIG ioctl.
>   - Trigger start of the virtual machine with VM_START ioctl.
>
> Co-developed-by: Prakruthi Deepak Heragu <quic_pheragu@xxxxxxxxxxx>
> Signed-off-by: Prakruthi Deepak Heragu <quic_pheragu@xxxxxxxxxxx>
> Signed-off-by: Elliot Berman <quic_eberman@xxxxxxxxxxx>

I point out a spelling error, but otherwise this looks OK to me.

Reviewed-by: Alex Elder <elder@xxxxxxxxxx>

> ---
>   drivers/virt/gunyah/vm_mgr.c    | 215 ++++++++++++++++++++++++++++++++
>   drivers/virt/gunyah/vm_mgr.h    |  11 ++
>   drivers/virt/gunyah/vm_mgr_mm.c |  20 +++
>   include/uapi/linux/gunyah.h     |  15 +++
>   4 files changed, 261 insertions(+)


. . .

> +static int gh_vm_ensure_started(struct gh_vm *ghvm)
> +{
> +	int ret;
> +
> +	ret = down_read_interruptible(&ghvm->status_lock);
> +	if (ret)
> +		return ret;
> +
> +	/* Unlikely because VM is typically started */
> +	if (unlikely(ghvm->vm_status == GH_RM_VM_STATUS_NO_STATE)) {
> +		up_read(&ghvm->status_lock);
> +		ret = gh_vm_start(ghvm);
> +		if (ret)
> +			return ret;
> +		/** gh_vm_start() is guaranteed to bring status out of
> +		 * GH_RM_VM_STATUS_LOAD, thus inifitely recursive call is not

s/inifitely/infinitely/

> +		 * possible
> +		 */
> +		return gh_vm_ensure_started(ghvm);
> +	}
> +
> +	/* Unlikely because VM is typically running */
> +	if (unlikely(ghvm->vm_status != GH_RM_VM_STATUS_RUNNING))
> +		ret = -ENODEV;
> +
> +	up_read(&ghvm->status_lock);
> +	return ret;
> +}
> +
>   static long gh_vm_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
>   {
>   	struct gh_vm *ghvm = filp->private_data;
. . .