Re: [Qemu-devel] [PATCH 2/5] apic: add send_msi() to APICCommonClass

[Igor Mammedov]

On Thu, 22 Sep 2016 23:04:29 +0200
Radim Krčmář <address@hidden> wrote:

> The MMIO based interface to APIC doesn't work well with MSIs that have
> upper address bits set (remapped x2APIC MSIs).  A specialized interface
> is a quick and dirty way to avoid the shortcoming.
> 
> Signed-off-by: Radim Krčmář <address@hidden>
> ---
>  hw/i386/kvm/apic.c              | 19 +++++++++++++------
>  hw/i386/xen/xen_apic.c          |  6 ++++++
>  hw/intc/apic.c                  |  6 ++++++
>  include/hw/i386/apic_internal.h |  4 ++++
>  4 files changed, 29 insertions(+), 6 deletions(-)
> 
> diff --git a/hw/i386/kvm/apic.c b/hw/i386/kvm/apic.c
> index feb00024f20c..7cc1acd63d32 100644
> --- a/hw/i386/kvm/apic.c
> +++ b/hw/i386/kvm/apic.c
> @@ -168,6 +168,17 @@ static void kvm_apic_external_nmi(APICCommonState *s)
>      run_on_cpu(CPU(s->cpu), do_inject_external_nmi, s);
>  }
>  
> +static void kvm_send_msi(MSIMessage *msg)
> +{
> +    int ret;
> +
> +    ret = kvm_irqchip_send_msi(kvm_state, *msg);
> +    if (ret < 0) {
> +        fprintf(stderr, "KVM: injection failed, MSI lost (%s)\n",
> +                strerror(-ret));
> +    }
> +}
> +
>  static uint64_t kvm_apic_mem_read(void *opaque, hwaddr addr,
>                                    unsigned size)
>  {
> @@ -178,13 +189,8 @@ static void kvm_apic_mem_write(void *opaque, hwaddr addr,
>                                 uint64_t data, unsigned size)
>  {
>      MSIMessage msg = { .address = addr, .data = data };
> -    int ret;
>  
> -    ret = kvm_irqchip_send_msi(kvm_state, msg);
> -    if (ret < 0) {
> -        fprintf(stderr, "KVM: injection failed, MSI lost (%s)\n",
> -                strerror(-ret));
> -    }
> +    kvm_send_msi(&msg);
>  }
>  
>  static const MemoryRegionOps kvm_apic_io_ops = {
> @@ -231,6 +237,7 @@ static void kvm_apic_class_init(ObjectClass *klass, void 
> *data)
>      k->enable_tpr_reporting = kvm_apic_enable_tpr_reporting;
>      k->vapic_base_update = kvm_apic_vapic_base_update;
>      k->external_nmi = kvm_apic_external_nmi;
> +    k->send_msi = kvm_send_msi;
>  }
>  
>  static const TypeInfo kvm_apic_info = {
> diff --git a/hw/i386/xen/xen_apic.c b/hw/i386/xen/xen_apic.c
> index 21d68ee04b0a..55769eba7ede 100644
> --- a/hw/i386/xen/xen_apic.c
> +++ b/hw/i386/xen/xen_apic.c
> @@ -68,6 +68,11 @@ static void xen_apic_external_nmi(APICCommonState *s)
>  {
>  }
>  
> +static void xen_send_msi(MSIMessage *msi)
> +{
> +    xen_hvm_inject_msi(msi->address, msi->data);
> +}
> +
>  static void xen_apic_class_init(ObjectClass *klass, void *data)
>  {
>      APICCommonClass *k = APIC_COMMON_CLASS(klass);
> @@ -78,6 +83,7 @@ static void xen_apic_class_init(ObjectClass *klass, void 
> *data)
>      k->get_tpr = xen_apic_get_tpr;
>      k->vapic_base_update = xen_apic_vapic_base_update;
>      k->external_nmi = xen_apic_external_nmi;
> +    k->send_msi = xen_send_msi;
>  }
>  
>  static const TypeInfo xen_apic_info = {
> diff --git a/hw/intc/apic.c b/hw/intc/apic.c
> index 7bd1d279c463..4f3fb44d05e4 100644
> --- a/hw/intc/apic.c
> +++ b/hw/intc/apic.c
> @@ -900,6 +900,11 @@ static void apic_unrealize(DeviceState *dev, Error 
> **errp)
>      local_apics[s->id] = NULL;
>  }
>  
> +static void apic_send_msi_struct(MSIMessage *msi)
> +{
> +    apic_send_msi(msi->address, msi->data);
> +}
why not to make apic_send_msi(MSIMessage *msi) instead of adding a wrapper?

Also when interface is switched to send_msi() in 3/5,
aren't you loosing following checks in apic_mem_writel():

    if (addr > 0xfff || !index) {                                               
  


> +
>  static void apic_class_init(ObjectClass *klass, void *data)
>  {
>      APICCommonClass *k = APIC_COMMON_CLASS(klass);
> @@ -913,6 +918,7 @@ static void apic_class_init(ObjectClass *klass, void 
> *data)
>      k->external_nmi = apic_external_nmi;
>      k->pre_save = apic_pre_save;
>      k->post_load = apic_post_load;
> +    k->send_msi = apic_send_msi_struct;
>  }
>  
>  static const TypeInfo apic_info = {
> diff --git a/include/hw/i386/apic_internal.h b/include/hw/i386/apic_internal.h
> index 9ba8a5c87f90..32b083ad2926 100644
> --- a/include/hw/i386/apic_internal.h
> +++ b/include/hw/i386/apic_internal.h
> @@ -146,6 +146,10 @@ typedef struct APICCommonClass
>      void (*pre_save)(APICCommonState *s);
>      void (*post_load)(APICCommonState *s);
>      void (*reset)(APICCommonState *s);
> +    /* send_msi emulates an APIC bus and its proper place would be in a new
> +     * device, but it's convenient to have it here for now.
> +     */
> +    void (*send_msi)(MSIMessage *msi);
>  } APICCommonClass;
>  
>  struct APICCommonState {