[PATCH v5 15/22] KVM: arm64: vgic-its: vgic_its_alloc_ite/device

[Christoffer Dall]

On Fri, Apr 14, 2017 at 12:15:27PM +0200, Eric Auger wrote:
> Add two new helpers to allocate an its ite and an its device.
> This will avoid duplication on restore path.
> 
> Signed-off-by: Eric Auger <eric.auger at redhat.com>
> Acked-by: Marc Zyngier <marc.zyngier at arm.com>
> 
> ---
> 
> v4 -> v5:
> - add Marc's A-b
> 
> v3 -> v4:
> - fix allocation
> - add comment about its_lock mutex hold
> 
> v1 -> v2:
> - report itt_size fix and remove ITE_SIZE
> - s/itte/ite/g
> ---
>  virt/kvm/arm/vgic/vgic-its.c | 73 ++++++++++++++++++++++++++++++--------------
>  1 file changed, 50 insertions(+), 23 deletions(-)
> 
> diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
> index 55267ab..56c5123 100644
> --- a/virt/kvm/arm/vgic/vgic-its.c
> +++ b/virt/kvm/arm/vgic/vgic-its.c
> @@ -742,6 +742,27 @@ static void vgic_its_free_collection(struct vgic_its *its, u32 coll_id)
>  	kfree(collection);
>  }
>  
> +/* Must be called with its_lock mutex held */
> +static int vgic_its_alloc_ite(struct its_device *device,
> +			       struct its_ite **itep,
> +			       struct its_collection *collection,
> +			       u32 lpi_id, u32 event_id)
> +{
> +	struct its_ite *ite;
> +
> +	ite = kzalloc(sizeof(*ite), GFP_KERNEL);
> +	if (!ite)
> +		return -ENOMEM;
> +
> +	ite->event_id	= event_id;
> +	ite->collection = collection;
> +	ite->lpi = lpi_id;
> +
> +	list_add_tail(&ite->ite_list, &device->itt_head);
> +	*itep = ite;
> +	return 0;
> +}

This static function should just return a 'struct its_ite *itep' and on
error you can return ERR_PTR(-ENOMEM).

> +
>  /*
>   * The MAPTI and MAPI commands map LPIs to ITTEs.
>   * Must be called with its_lock mutex held.
> @@ -755,7 +776,7 @@ static int vgic_its_cmd_handle_mapi(struct kvm *kvm, struct vgic_its *its,
>  	struct its_ite *ite;
>  	struct its_device *device;
>  	struct its_collection *collection, *new_coll = NULL;
> -	int lpi_nr;
> +	int lpi_nr, ret;
>  	struct vgic_irq *irq;
>  
>  	device = find_its_device(its, device_id);
> @@ -785,19 +806,13 @@ static int vgic_its_cmd_handle_mapi(struct kvm *kvm, struct vgic_its *its,
>  		new_coll = collection;
>  	}
>  
> -	ite = kzalloc(sizeof(struct its_ite), GFP_KERNEL);
> -	if (!ite) {
> +	ret = vgic_its_alloc_ite(device, &ite, collection, lpi_nr, event_id);
> +	if (ret) {
>  		if (new_coll)
>  			vgic_its_free_collection(its, coll_id);
> -		return -ENOMEM;
> +		return ret;
>  	}
>  
> -	ite->event_id	= event_id;
> -	list_add_tail(&ite->ite_list, &device->itt_head);
> -
> -	ite->collection = collection;
> -	ite->lpi = lpi_nr;
> -
>  	irq = vgic_add_lpi(kvm, lpi_nr);
>  	if (IS_ERR(irq)) {
>  		if (new_coll)
> @@ -836,6 +851,29 @@ static void vgic_its_unmap_device(struct kvm *kvm, struct its_device *device)
>  	kfree(device);
>  }
>  
> +/* Must be called with its_lock mutex held */
> +static int vgic_its_alloc_device(struct vgic_its *its,
> +				 struct its_device **devp,
> +				 u32 device_id, gpa_t itt_addr,
> +				 u8 nb_eventid_bits)
> +{
> +	struct its_device *device;
> +
> +	device = kzalloc(sizeof(*device), GFP_KERNEL);
> +	if (!device)
> +		return -ENOMEM;
> +
> +	device->device_id = device_id;
> +	device->itt_addr = itt_addr;
> +	device->nb_eventid_bits = nb_eventid_bits;
> +	INIT_LIST_HEAD(&device->itt_head);
> +
> +	list_add_tail(&device->dev_list, &its->device_list);
> +	*devp = device;
> +
> +	return 0;
> +}

also here, return ERR_PTR

> +
>  /*
>   * MAPD maps or unmaps a device ID to Interrupt Translation Tables (ITTs).
>   * Must be called with the its_lock mutex held.
> @@ -872,19 +910,8 @@ static int vgic_its_cmd_handle_mapd(struct kvm *kvm, struct vgic_its *its,
>  	if (!valid)
>  		return 0;
>  
> -	device = kzalloc(sizeof(struct its_device), GFP_KERNEL);
> -	if (!device)
> -		return -ENOMEM;
> -
> -	device->device_id = device_id;
> -	device->nb_eventid_bits = nb_eventid_bits;
> -	device->itt_addr = itt_addr;
> -
> -	INIT_LIST_HEAD(&device->itt_head);
> -
> -	list_add_tail(&device->dev_list, &its->device_list);
> -
> -	return 0;
> +	return vgic_its_alloc_device(its, &device, device_id,
> +				     itt_addr, nb_eventid_bits);
>  }
>  
>  /*
> -- 
> 2.5.5
> 
Thanks,
-Christoffer