Re: [RFC 1/8] ioregionfd: introduce a syscall and memory API

[David Hildenbrand]

Looks straight forward to me.

[...]

>  
> +int kvm_set_ioregionfd(struct kvm_ioregion *ioregionfd)
> +{
> +    KVMState *s = kvm_state;
> +    int ret = -1;
> +
> +    ret = kvm_vm_ioctl(s, KVM_SET_IOREGION, ioregionfd);
> +    if (ret < 0) {
> +        error_report("Failed SET_IOREGION syscall ret is %d", ret);

Maybe print the textual representation via strerror(-ret).

> +    }
> +    return ret;
> +}
> +
>  static int do_kvm_destroy_vcpu(CPUState *cpu)
>  {
>      KVMState *s = kvm_state;
> @@ -1635,6 +1648,104 @@ static void kvm_io_ioeventfd_del(MemoryListener 
> *listener,
>      }
>  }
>  
> +static void kvm_mem_ioregionfd_add(MemoryListener *listener,
> +                                   MemoryRegionSection *section,
> +                                   uint64_t data,
> +                                   int fd)
> +{
> +
> +    struct kvm_ioregion ioregionfd;
> +    int r = -1;
> +
> +    ioregionfd.guest_paddr = section->offset_within_address_space;
> +    ioregionfd.memory_size = int128_get64(section->size);
> +    ioregionfd.user_data = data;
> +    ioregionfd.read_fd = fd;
> +    ioregionfd.write_fd = fd;
> +    ioregionfd.flags = 0;
> +    memset(&ioregionfd.pad, 0, sizeof(ioregionfd.pad));
> +
> +    r = kvm_set_ioregionfd(&ioregionfd);
> +    if (r < 0) {
> +        fprintf(stderr, "%s: error adding ioregionfd: %s (%d)\n,",
> +                __func__, strerror(-r), -r);

Oh, you're actually printing the error again? Why error_report() above
and here fprintf?

[...]

>  void kvm_memory_listener_register(KVMState *s, KVMMemoryListener *kml,
>                                    AddressSpace *as, int as_id, const char 
> *name)
>  {
> @@ -1679,6 +1790,12 @@ static MemoryListener kvm_io_listener = {
>      .priority = 10,
>  };
>  
> +static MemoryListener kvm_ioregion_listener = {
> +    .ioregionfd_add = kvm_io_ioregionfd_add,
> +    .ioregionfd_del = kvm_io_ioregionfd_del,
> +    .priority = 10,
> +};
> +
>  int kvm_set_irq(KVMState *s, int irq, int level)
>  {
>      struct kvm_irq_level event;
> @@ -2564,6 +2681,9 @@ static int kvm_init(MachineState *ms)
>      kvm_ioeventfd_any_length_allowed =
>          (kvm_check_extension(s, KVM_CAP_IOEVENTFD_ANY_LENGTH) > 0);
>  
> +    kvm_ioregionfds_allowed =
> +        (kvm_check_extension(s, KVM_CAP_IOREGIONFD) > 0);
> +
>      kvm_state = s;
>  
>      ret = kvm_arch_init(ms, s);
> @@ -2585,6 +2705,12 @@ static int kvm_init(MachineState *ms)
>          s->memory_listener.listener.eventfd_add = kvm_mem_ioeventfd_add;
>          s->memory_listener.listener.eventfd_del = kvm_mem_ioeventfd_del;
>      }
> +
> +    if (kvm_ioregionfds_allowed) {
> +        s->memory_listener.listener.ioregionfd_add = kvm_mem_ioregionfd_add;
> +        s->memory_listener.listener.ioregionfd_del = kvm_mem_ioregionfd_del;
> +    }
> +
>      s->memory_listener.listener.coalesced_io_add = kvm_coalesce_mmio_region;
>      s->memory_listener.listener.coalesced_io_del = 
> kvm_uncoalesce_mmio_region;
>  
> @@ -2594,6 +2720,12 @@ static int kvm_init(MachineState *ms)
>          memory_listener_register(&kvm_io_listener,
>                                   &address_space_io);
>      }
> +
> +    if (kvm_ioregionfds_allowed) {
> +        memory_listener_register(&kvm_ioregion_listener,
> +                                 &address_space_io);
> +    }
> +
>      memory_listener_register(&kvm_coalesced_pio_listener,
>                               &address_space_io);
>  

Why are we using a single memory listener for address_space_memory but
individual listeners for address_space_io?

IOW, wey don't we have &s->io_listener ?

-- 
Thanks,

David / dhildenb