Re: [Qemu-devel] [PATCH v10 17/26] x86-iommu: introduce IEC notifiers

[Paolo Bonzini]

On 21/06/2016 09:47, Peter Xu wrote:
> This patch introduces x86 IOMMU IEC (Interrupt Entry Cache)
> invalidation notifier list. When vIOMMU receives IEC invalidate
> request, all the registered units will be notified with specific
> invalidation requests.
> 
> Intel IOMMU is the first provider that generates such a event.
> 
> Signed-off-by: Peter Xu <address@hidden>

Please consider switching this to a NotifierList.

Paolo

> ---
>  hw/i386/intel_iommu.c          | 36 +++++++++++++++++++++++++++++-------
>  hw/i386/intel_iommu_internal.h | 24 ++++++++++++++++++++----
>  hw/i386/x86-iommu.c            | 29 +++++++++++++++++++++++++++++
>  include/hw/i386/x86-iommu.h    | 40 ++++++++++++++++++++++++++++++++++++++++
>  trace-events                   |  3 +++
>  5 files changed, 121 insertions(+), 11 deletions(-)
> 
> diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
> index 0eaffc6..11cb495 100644
> --- a/hw/i386/intel_iommu.c
> +++ b/hw/i386/intel_iommu.c
> @@ -904,6 +904,12 @@ static void vtd_root_table_setup(IntelIOMMUState *s)
>                  (s->root_extended ? "(extended)" : ""));
>  }
>  
> +static void vtd_iec_notify_all(IntelIOMMUState *s, bool global,
> +                               uint32_t index, uint32_t mask)
> +{
> +    x86_iommu_iec_notify_all(X86_IOMMU_DEVICE(s), global, index, mask);
> +}
> +
>  static void vtd_interrupt_remap_table_setup(IntelIOMMUState *s)
>  {
>      uint64_t value = 0;
> @@ -911,7 +917,8 @@ static void 
> vtd_interrupt_remap_table_setup(IntelIOMMUState *s)
>      s->intr_size = 1UL << ((value & VTD_IRTA_SIZE_MASK) + 1);
>      s->intr_root = value & VTD_IRTA_ADDR_MASK;
>  
> -    /* TODO: invalidate interrupt entry cache */
> +    /* Notify global invalidation */
> +    vtd_iec_notify_all(s, true, 0, 0);
>  
>      VTD_DPRINTF(CSR, "int remap table addr 0x%"PRIx64 " size %"PRIu32,
>                  s->intr_root, s->intr_size);
> @@ -1413,6 +1420,21 @@ static bool vtd_process_iotlb_desc(IntelIOMMUState *s, 
> VTDInvDesc *inv_desc)
>      return true;
>  }
>  
> +static bool vtd_process_inv_iec_desc(IntelIOMMUState *s,
> +                                     VTDInvDesc *inv_desc)
> +{
> +    VTD_DPRINTF(INV, "inv ir glob %d index %d mask %d",
> +                inv_desc->iec.granularity,
> +                inv_desc->iec.index,
> +                inv_desc->iec.index_mask);
> +
> +    vtd_iec_notify_all(s, !inv_desc->iec.granularity,
> +                       inv_desc->iec.index,
> +                       inv_desc->iec.index_mask);
> +
> +    return true;
> +}
> +
>  static bool vtd_process_inv_desc(IntelIOMMUState *s)
>  {
>      VTDInvDesc inv_desc;
> @@ -1453,12 +1475,12 @@ static bool vtd_process_inv_desc(IntelIOMMUState *s)
>          break;
>  
>      case VTD_INV_DESC_IEC:
> -        VTD_DPRINTF(INV, "Interrupt Entry Cache Invalidation "
> -                    "not implemented yet");
> -        /*
> -         * Since currently we do not cache interrupt entries, we can
> -         * just mark this descriptor as "good" and move on.
> -         */
> +        VTD_DPRINTF(INV, "Invalidation Interrupt Entry Cache "
> +                    "Descriptor hi 0x%"PRIx64 " lo 0x%"PRIx64,
> +                    inv_desc.hi, inv_desc.lo);
> +        if (!vtd_process_inv_iec_desc(s, &inv_desc)) {
> +            return false;
> +        }
>          break;
>  
>      default:
> diff --git a/hw/i386/intel_iommu_internal.h b/hw/i386/intel_iommu_internal.h
> index e1a08cb..10c20fe 100644
> --- a/hw/i386/intel_iommu_internal.h
> +++ b/hw/i386/intel_iommu_internal.h
> @@ -296,12 +296,28 @@ typedef enum VTDFaultReason {
>  
>  #define VTD_CONTEXT_CACHE_GEN_MAX       0xffffffffUL
>  
> +/* Interrupt Entry Cache Invalidation Descriptor: VT-d 6.5.2.7. */
> +struct VTDInvDescIEC {
> +    uint32_t type:4;            /* Should always be 0x4 */
> +    uint32_t granularity:1;     /* If set, it's global IR invalidation */
> +    uint32_t resved_1:22;
> +    uint32_t index_mask:5;      /* 2^N for continuous int invalidation */
> +    uint32_t index:16;          /* Start index to invalidate */
> +    uint32_t reserved_2:16;
> +};
> +typedef struct VTDInvDescIEC VTDInvDescIEC;
> +
>  /* Queued Invalidation Descriptor */
> -struct VTDInvDesc {
> -    uint64_t lo;
> -    uint64_t hi;
> +union VTDInvDesc {
> +    struct {
> +        uint64_t lo;
> +        uint64_t hi;
> +    };
> +    union {
> +        VTDInvDescIEC iec;
> +    };
>  };
> -typedef struct VTDInvDesc VTDInvDesc;
> +typedef union VTDInvDesc VTDInvDesc;
>  
>  /* Masks for struct VTDInvDesc */
>  #define VTD_INV_DESC_TYPE               0xf
> diff --git a/hw/i386/x86-iommu.c b/hw/i386/x86-iommu.c
> index 4280839..ce26b2a 100644
> --- a/hw/i386/x86-iommu.c
> +++ b/hw/i386/x86-iommu.c
> @@ -22,6 +22,33 @@
>  #include "hw/boards.h"
>  #include "hw/i386/x86-iommu.h"
>  #include "qemu/error-report.h"
> +#include "trace.h"
> +
> +void x86_iommu_iec_register_notifier(X86IOMMUState *iommu,
> +                                     iec_notify_fn fn, void *data)
> +{
> +    IEC_Notifier *notifier = g_new0(IEC_Notifier, 1);
> +
> +    notifier->iec_notify = fn;
> +    notifier->private = data;
> +
> +    QLIST_INSERT_HEAD(&iommu->iec_notifiers, notifier, list);
> +}
> +
> +void x86_iommu_iec_notify_all(X86IOMMUState *iommu, bool global,
> +                              uint32_t index, uint32_t mask)
> +{
> +    IEC_Notifier *notifier;
> +
> +    trace_x86_iommu_iec_notify(global, index, mask);
> +
> +    QLIST_FOREACH(notifier, &iommu->iec_notifiers, list) {
> +        if (notifier->iec_notify) {
> +            notifier->iec_notify(notifier->private, global,
> +                                 index, mask);
> +        }
> +    }
> +}
>  
>  /* Default X86 IOMMU device */
>  static X86IOMMUState *x86_iommu_default = NULL;
> @@ -46,7 +73,9 @@ X86IOMMUState *x86_iommu_get_default(void)
>  
>  static void x86_iommu_realize(DeviceState *dev, Error **errp)
>  {
> +    X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(dev);
>      X86IOMMUClass *x86_class = X86_IOMMU_GET_CLASS(dev);
> +    QLIST_INIT(&x86_iommu->iec_notifiers);
>      if (x86_class->realize) {
>          x86_class->realize(dev, errp);
>      }
> diff --git a/include/hw/i386/x86-iommu.h b/include/hw/i386/x86-iommu.h
> index b419ae5..af80d15 100644
> --- a/include/hw/i386/x86-iommu.h
> +++ b/include/hw/i386/x86-iommu.h
> @@ -49,9 +49,28 @@ struct X86IOMMUClass {
>                       MSIMessage *dst, uint16_t sid);
>  };
>  
> +/**
> + * iec_notify_fn - IEC (Interrupt Entry Cache) notifier hook,
> + *                 triggered when IR invalidation happens.
> + * @private: private data
> + * @global: whether this is a global IEC invalidation
> + * @index: IRTE index to invalidate (start from)
> + * @mask: invalidation mask
> + */
> +typedef void (*iec_notify_fn)(void *private, bool global,
> +                              uint32_t index, uint32_t mask);
> +
> +struct IEC_Notifier {
> +    iec_notify_fn iec_notify;
> +    void *private;
> +    QLIST_ENTRY(IEC_Notifier) list;
> +};
> +typedef struct IEC_Notifier IEC_Notifier;
> +
>  struct X86IOMMUState {
>      SysBusDevice busdev;
>      bool intr_supported;        /* Whether vIOMMU supports IR */
> +    QLIST_HEAD(, IEC_Notifier) iec_notifiers; /* IEC notify list */
>  };
>  
>  /**
> @@ -60,4 +79,25 @@ struct X86IOMMUState {
>   */
>  X86IOMMUState *x86_iommu_get_default(void);
>  
> +/**
> + * x86_iommu_iec_register_notifier - register IEC (Interrupt Entry
> + *                                   Cache) notifiers
> + * @iommu: IOMMU device to register
> + * @fn: IEC notifier hook function
> + * @data: notifier private data
> + */
> +void x86_iommu_iec_register_notifier(X86IOMMUState *iommu,
> +                                     iec_notify_fn fn, void *data);
> +
> +/**
> + * x86_iommu_iec_notify_all - Notify IEC invalidations
> + * @iommu: IOMMU device that sends the notification
> + * @global: whether this is a global invalidation. If true, @index
> + *          and @mask are undefined.
> + * @index: starting index of interrupt entry to invalidate
> + * @mask: index mask for the invalidation
> + */
> +void x86_iommu_iec_notify_all(X86IOMMUState *iommu, bool global,
> +                              uint32_t index, uint32_t mask);
> +
>  #endif
> diff --git a/trace-events b/trace-events
> index 2982f64..20df932 100644
> --- a/trace-events
> +++ b/trace-events
> @@ -2209,3 +2209,6 @@ gicv3_redist_send_sgi(uint32_t cpu, int irq) "GICv3 
> redistributor %x pending SGI
>  
>  # target-i386/kvm.c
>  kvm_x86_fixup_msi_error(uint32_t gsi) "VT-d failed to remap interrupt for 
> GSI %" PRIu32
> +
> +# hw/i386/x86-iommu.c
> +x86_iommu_iec_notify(bool global, uint32_t index, uint32_t mask) "Notify IEC 
> invalidation: global=%d index=%" PRIu32 " mask=%" PRIu32
>