Re: [PATCH 14/32] KVM: s390: pci: do initial setup for AEN interpretation

Pierre Morel
2021-12-10T09:53:24Z

On 12/7/21 21:57, Matthew Rosato wrote:
> Initial setup for Adapter Event Notification Interpretation for zPCI
> passthrough devices. Specifically, allocate a structure for forwarding of
> adapter events and pass the address of this structure to firmware.
>
> Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
> ---
> arch/s390/include/asm/pci_insn.h | 12 ++++
> arch/s390/kvm/interrupt.c | 17 +++++
> arch/s390/kvm/kvm-s390.c | 3 +
> arch/s390/kvm/pci.c | 113 +++++++++++++++++++++++++++++++
> arch/s390/kvm/pci.h | 42 ++++++++++++
> 5 files changed, 187 insertions(+)
> create mode 100644 arch/s390/kvm/pci.h
>
> diff --git a/arch/s390/include/asm/pci_insn.h b/arch/s390/include/asm/pci_insn.h
> index 5331082fa516..e5f57cfe1d45 100644
> --- a/arch/s390/include/asm/pci_insn.h
> +++ b/arch/s390/include/asm/pci_insn.h
> @@ -101,6 +101,7 @@ struct zpci_fib {
> /* Set Interruption Controls Operation Controls */
> #define SIC_IRQ_MODE_ALL 0
> #define SIC_IRQ_MODE_SINGLE 1
> +#define SIC_SET_AENI_CONTROLS 2
> #define SIC_IRQ_MODE_DIRECT 4
> #define SIC_IRQ_MODE_D_ALL 16
> #define SIC_IRQ_MODE_D_SINGLE 17
> @@ -127,9 +128,20 @@ struct zpci_cdiib {
> u64 : 64;
> } __packed __aligned(8);
>
> +/* adapter interruption parameters block */
> +struct zpci_aipb {
> + u64 faisb;
> + u64 gait;
> + u16 : 13;
> + u16 afi : 3;
> + u32 : 32;
> + u16 faal;
> +} __packed __aligned(8);
> +
> union zpci_sic_iib {
> struct zpci_diib diib;
> struct zpci_cdiib cdiib;
> + struct zpci_aipb aipb;
> };
>
> DECLARE_STATIC_KEY_FALSE(have_mio);
> diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
> index f9b872e358c6..4efe0e95a40f 100644
> --- a/arch/s390/kvm/interrupt.c
> +++ b/arch/s390/kvm/interrupt.c
> @@ -32,6 +32,7 @@
> #include "kvm-s390.h"
> #include "gaccess.h"
> #include "trace-s390.h"
> +#include "pci.h"
>
> #define PFAULT_INIT 0x0600
> #define PFAULT_DONE 0x0680
> @@ -3276,8 +3277,16 @@ static struct airq_struct gib_alert_irq = {
>
> void kvm_s390_gib_destroy(void)
> {
> + struct zpci_aift *aift;
> +
> if (!gib)
> return;
> + aift = kvm_s390_pci_get_aift();
> + if (aift) {
> + mutex_lock(&aift->lock);
> + kvm_s390_pci_aen_exit();

Shouldn't we check for CONFIG_PCI and sclp.gas_aeni here as in gib_init ?

> + mutex_unlock(&aift->lock);
> + }
> chsc_sgib(0);
> unregister_adapter_interrupt(&gib_alert_irq);
> free_page((unsigned long)gib);
> @@ -3315,6 +3324,14 @@ int kvm_s390_gib_init(u8 nisc)
> goto out_unreg_gal;
> }
>
> + if (IS_ENABLED(CONFIG_PCI) && sclp.has_aeni) {
> + if (kvm_s390_pci_aen_init(nisc)) {
> + pr_err("Initializing AEN for PCI failed\n");
> + rc = -EIO;
> + goto out_unreg_gal;
> + }
> + }
> +
> KVM_EVENT(3, "gib 0x%pK (nisc=%d) initialized", gib, gib->nisc);
> goto out;
>
> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
> index 14a18ba5ff2c..9cd3c8eb59e8 100644
> --- a/arch/s390/kvm/kvm-s390.c
> +++ b/arch/s390/kvm/kvm-s390.c
> @@ -48,6 +48,7 @@
> #include <asm/fpu/api.h>
> #include "kvm-s390.h"
> #include "gaccess.h"
> +#include "pci.h"
>
> #define CREATE_TRACE_POINTS
> #include "trace.h"
> @@ -503,6 +504,8 @@ int kvm_arch_init(void *opaque)
> goto out;
> }
>
> + kvm_s390_pci_init();
> +
> rc = kvm_s390_gib_init(GAL_ISC);
> if (rc)
> goto out;
> diff --git a/arch/s390/kvm/pci.c b/arch/s390/kvm/pci.c
> index ecfc458a5b39..f0e5386ff943 100644
> --- a/arch/s390/kvm/pci.c
> +++ b/arch/s390/kvm/pci.c
> @@ -10,6 +10,113 @@
> #include <linux/kvm_host.h>
> #include <linux/pci.h>
> #include <asm/kvm_pci.h>
> +#include "pci.h"
> +
> +static struct zpci_aift aift;
> +
> +static inline int __set_irq_noiib(u16 ctl, u8 isc)
> +{
> + union zpci_sic_iib iib = {{0}};
> +
> + return zpci_set_irq_ctrl(ctl, isc, &iib);
> +}
> +
> +struct zpci_aift *kvm_s390_pci_get_aift(void)
> +{
> + return &aift;
> +}
> +
> +/* Caller must hold the aift lock before calling this function */
> +void kvm_s390_pci_aen_exit(void)
> +{
> + struct zpci_gaite *gait;
> + unsigned long flags;
> + struct airq_iv *sbv;
> + struct kvm_zdev **gait_kzdev;
> + int size;
> +
> + /* Clear the GAIT and forwarding summary vector */
> + __set_irq_noiib(SIC_SET_AENI_CONTROLS, 0);

Why don't we use the PCI ISC here?

...snip...

--
Pierre Morel
IBM Lab Boeblingen