Re: [PATCH v1 3/7] vfio: ap: AP Queue Interrupt structures definitions

[Tony Krowiak <akrowiak@linux.ibm.com>]

On 10/31/18 2:12 PM, Pierre Morel wrote:
> We define all the structures we need to let GISA handle
> the AP Queues Interrupt.
> 
> This patch defines the inline assembler for AP Queue Interrupt
> Control instruction with GISA, some utilities to manipulate
> the data in the registers used by this instruction.
> 
> We also define new ap_matrix components to handle interruptions
> and adapter mapping.
> 
> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
> ---
>   drivers/s390/crypto/vfio_ap_private.h | 77 +++++++++++++++++++++++++++
>   1 file changed, 77 insertions(+)
> 
> diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h
> index 5675492233c7..45103865bd7f 100644
> --- a/drivers/s390/crypto/vfio_ap_private.h
> +++ b/drivers/s390/crypto/vfio_ap_private.h
> @@ -74,15 +74,92 @@ struct ap_matrix {
>    * @group_notifier: notifier block used for specifying callback function for
>    *		    handling the VFIO_GROUP_NOTIFY_SET_KVM event
>    * @kvm:	the struct holding guest's state
> + * @map:	the adapter information for QEMU mapping
> + * @gisc:	the Guest ISC
>    */
>   struct ap_matrix_mdev {
>   	struct list_head node;
>   	struct ap_matrix matrix;
>   	struct notifier_block group_notifier;
>   	struct kvm *kvm;
> +	struct s390_map_info *map;
> +	unsigned char gisc;
>   };
>   
>   extern int vfio_ap_mdev_register(void);
>   extern void vfio_ap_mdev_unregister(void);
>   
> +/* AP Queue Interrupt Control associated structures and functions */
> +struct aqic_gisa {
> +	uint8_t  rzone;
> +	uint8_t  izone;
> +	unsigned	ir:1;
> +	unsigned	reserved1:4;
> +	unsigned	gisc:3;
> +	unsigned	reserved2:6;
> +	unsigned	f:2;
> +	unsigned	reserved3:1;
> +	unsigned	gisao:27;
> +	unsigned	t:1;
> +	unsigned	isc:3;
> +}  __packed __aligned(8);

This struct is redundant with the 'struct ap_qirq_ctrl'
defined in arch/s390/include/asm/ap.h. That file also includes
the asm for the ap_aqic function.

> +
> +struct ap_status {
> +	unsigned	e:1;
> +	unsigned	r:1;
> +	unsigned	f:1;
> +	unsigned	reserved:4;
> +	unsigned	i:1;
> +	unsigned	rc:8;
> +	unsigned	pad:16;
> +}  __packed __aligned(4);
> +
> +static inline uint32_t status2reg(struct ap_status a)
> +{
> +	return *(uint32_t *)(&a);
> +}
> +
> +static inline struct ap_status reg2status(uint32_t r)
> +{
> +	return *(struct ap_status *)(&r);
> +}
> +
> +static inline struct aqic_gisa reg2aqic(uint64_t r)
> +{
> +	return *((struct aqic_gisa *)&r);
> +}
> +
> +static inline uint64_t aqic2reg(struct aqic_gisa a)
> +{
> +	return *((uint64_t *)&a);
> +}
> +
> +/**
> + * ap_host_aqic - Issue the host AQIC instruction.
> + * @apqn is the AP queue number
> + * @gr1  the caller must have setup the register
> + *       with GISA address and format, with interrupt
> + *       request, ISC and guest ISC
> + * @gr2  the caller must have setup the register
> + *       to the guest NIB physical address
> + *
> + * issue the AQIC PQAP instruction and return the AP status
> + * word
> + */
> +static inline uint32_t ap_host_aqic(uint64_t apqn, uint64_t gr1,
> +				    uint64_t gr2)
> +

> +	register unsigned long reg0 asm ("0") = apqn | (3UL << 24);
> +	register unsigned long reg1_in asm ("1") = gr1;
> +	register uint32_t reg1_out asm ("1");
> +	register unsigned long reg2 asm ("2") = gr2;
> +
> +	asm volatile(
> +		".long 0xb2af0000"	  /* PQAP(AQIC) */
> +		: "+d" (reg0), "+d" (reg1_in), "=d" (reg1_out), "+d" (reg2)
> +		:
> +		: "cc");
> +	return reg1_out;
> +}

This function is redundant to the ap_aqic function in
arch/s390/include/asm/ap.h

> +
>   #endif /* _VFIO_AP_PRIVATE_H_ */
>