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

Pierre Morel
2021-12-10T10:54:39Z

On 12/10/21 10:54, Pierre Morel wrote:
>
>
> 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?

hum OK, sorry, isc is ignored for SIC_SET_AENI_CONTROLS

>
> ...snip...
>

--
Pierre Morel
IBM Lab Boeblingen