Re: [RFT][PATCH v1 1/6] vfio/ap: Pass in physical address of ind to ap_aqic()

[Harald Freudenberger <freude@linux.ibm.com>]

On 2022-06-17 01:52, Nicolin Chen wrote:
> The ap_aqic() is called by vfio_ap_irq_enable() where it passes in a
> virt value that's casted from a physical address "h_nib". Inside the
> ap_aqic(), it does virt_to_phys() again.
> 
> Since ap_aqic() needs a physical address, let's just pass in a pa of
> ind directly. So change the "ind" to "pa_ind".
> 
> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
> ---
>  arch/s390/include/asm/ap.h        | 6 +++---
>  drivers/s390/crypto/ap_queue.c    | 2 +-
>  drivers/s390/crypto/vfio_ap_ops.c | 7 ++++---
>  3 files changed, 8 insertions(+), 7 deletions(-)
> 
> diff --git a/arch/s390/include/asm/ap.h b/arch/s390/include/asm/ap.h
> index b515cfa62bd9..f508f5025e38 100644
> --- a/arch/s390/include/asm/ap.h
> +++ b/arch/s390/include/asm/ap.h
> @@ -227,13 +227,13 @@ struct ap_qirq_ctrl {
>   * ap_aqic(): Control interruption for a specific AP.
>   * @qid: The AP queue number
>   * @qirqctrl: struct ap_qirq_ctrl (64 bit value)
> - * @ind: The notification indicator byte
> + * @pa_ind: Physical address of the notification indicator byte
>   *
>   * Returns AP queue status.
>   */
>  static inline struct ap_queue_status ap_aqic(ap_qid_t qid,
>  					     struct ap_qirq_ctrl qirqctrl,
> -					     void *ind)
> +					     phys_addr_t pa_ind)
>  {
>  	unsigned long reg0 = qid | (3UL << 24);  /* fc 3UL is AQIC */
>  	union {
> @@ -241,7 +241,7 @@ static inline struct ap_queue_status 
> ap_aqic(ap_qid_t qid,
>  		struct ap_qirq_ctrl qirqctrl;
>  		struct ap_queue_status status;
>  	} reg1;
> -	unsigned long reg2 = virt_to_phys(ind);
> +	unsigned long reg2 = pa_ind;
> 
>  	reg1.qirqctrl = qirqctrl;
> 
> diff --git a/drivers/s390/crypto/ap_queue.c 
> b/drivers/s390/crypto/ap_queue.c
> index c48b0db824e3..a32457b4cbb8 100644
> --- a/drivers/s390/crypto/ap_queue.c
> +++ b/drivers/s390/crypto/ap_queue.c
> @@ -34,7 +34,7 @@ static int ap_queue_enable_irq(struct ap_queue *aq, 
> void *ind)
> 
>  	qirqctrl.ir = 1;
>  	qirqctrl.isc = AP_ISC;
> -	status = ap_aqic(aq->qid, qirqctrl, ind);
> +	status = ap_aqic(aq->qid, qirqctrl, virt_to_phys(ind));
>  	switch (status.response_code) {
>  	case AP_RESPONSE_NORMAL:
>  	case AP_RESPONSE_OTHERWISE_CHANGED:
> diff --git a/drivers/s390/crypto/vfio_ap_ops.c
> b/drivers/s390/crypto/vfio_ap_ops.c
> index a7d2a95796d3..bb869b28cebd 100644
> --- a/drivers/s390/crypto/vfio_ap_ops.c
> +++ b/drivers/s390/crypto/vfio_ap_ops.c
> @@ -154,7 +154,7 @@ static struct ap_queue_status
> vfio_ap_irq_disable(struct vfio_ap_queue *q)
>  	int retries = 5;
> 
>  	do {
> -		status = ap_aqic(q->apqn, aqic_gisa, NULL);
> +		status = ap_aqic(q->apqn, aqic_gisa, 0);
>  		switch (status.response_code) {
>  		case AP_RESPONSE_OTHERWISE_CHANGED:
>  		case AP_RESPONSE_NORMAL:
> @@ -245,7 +245,8 @@ static struct ap_queue_status
> vfio_ap_irq_enable(struct vfio_ap_queue *q,
>  	struct kvm_s390_gisa *gisa;
>  	int nisc;
>  	struct kvm *kvm;
> -	unsigned long h_nib, g_pfn, h_pfn;
> +	unsigned long g_pfn, h_pfn;
> +	phys_addr_t h_nib;
>  	int ret;
> 
>  	/* Verify that the notification indicator byte address is valid */
> @@ -290,7 +291,7 @@ static struct ap_queue_status
> vfio_ap_irq_enable(struct vfio_ap_queue *q,
>  	aqic_gisa.ir = 1;
>  	aqic_gisa.gisa = (uint64_t)gisa >> 4;
> 
> -	status = ap_aqic(q->apqn, aqic_gisa, (void *)h_nib);
> +	status = ap_aqic(q->apqn, aqic_gisa, h_nib);
>  	switch (status.response_code) {
>  	case AP_RESPONSE_NORMAL:
>  		/* See if we did clear older IRQ configuration */
Add my Reviewed-By: Harald Freudenberger <freude@linux.ibm.com>