Re: [Qemu-devel] [PATCH v10 02/26] x86-iommu: provide x86_iommu_get_default

["Michael S. Tsirkin" <mst@redhat.com>]

On Tue, Jun 21, 2016 at 03:47:30PM +0800, Peter Xu wrote:
> Instead of searching the device tree every time, one static variable is
> declared for the default system x86 IOMMU device.  Also, some VT-d
> macros are replaced by x86 ones.

In the future pls don't mix unrelated changes in same patch like this.

> 
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>  hw/i386/acpi-build.c          |  9 ++-------
>  hw/i386/intel_iommu.c         |  9 ++++++---
>  hw/i386/x86-iommu.c           | 23 +++++++++++++++++++++++
>  include/hw/i386/intel_iommu.h |  1 -
>  include/hw/i386/x86-iommu.h   |  9 +++++++++
>  5 files changed, 40 insertions(+), 11 deletions(-)
> 
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index 8ca2032..161f089 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -50,7 +50,7 @@
>  #include "hw/i386/ich9.h"
>  #include "hw/pci/pci_bus.h"
>  #include "hw/pci-host/q35.h"
> -#include "hw/i386/intel_iommu.h"
> +#include "hw/i386/x86-iommu.h"
>  #include "hw/timer/hpet.h"
>  
>  #include "hw/acpi/aml-build.h"
> @@ -2500,12 +2500,7 @@ static bool acpi_get_mcfg(AcpiMcfgInfo *mcfg)
>  
>  static bool acpi_has_iommu(void)
>  {
> -    bool ambiguous;
> -    Object *intel_iommu;
> -
> -    intel_iommu = object_resolve_path_type("", TYPE_INTEL_IOMMU_DEVICE,
> -                                           &ambiguous);
> -    return intel_iommu && !ambiguous;
> +    return !!x86_iommu_get_default();
>  }
>  
>  static
> diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
> index 2734f6b..1936c41 100644
> --- a/hw/i386/intel_iommu.c
> +++ b/hw/i386/intel_iommu.c
> @@ -26,6 +26,8 @@
>  #include "hw/pci/pci.h"
>  #include "hw/pci/pci_bus.h"
>  #include "hw/i386/pc.h"
> +#include "hw/boards.h"
> +#include "hw/i386/x86-iommu.h"
>  
>  /*#define DEBUG_INTEL_IOMMU*/
>  #ifdef DEBUG_INTEL_IOMMU
> @@ -192,7 +194,7 @@ static void vtd_reset_context_cache(IntelIOMMUState *s)
>  
>      VTD_DPRINTF(CACHE, "global context_cache_gen=1");
>      while (g_hash_table_iter_next (&bus_it, NULL, (void**)&vtd_bus)) {
> -        for (devfn_it = 0; devfn_it < VTD_PCI_DEVFN_MAX; ++devfn_it) {
> +        for (devfn_it = 0; devfn_it < X86_IOMMU_PCI_DEVFN_MAX; ++devfn_it) {
>              vtd_as = vtd_bus->dev_as[devfn_it];
>              if (!vtd_as) {
>                  continue;
> @@ -964,7 +966,7 @@ static void vtd_context_device_invalidate(IntelIOMMUState *s,
>      vtd_bus = vtd_find_as_from_bus_num(s, VTD_SID_TO_BUS(source_id));
>      if (vtd_bus) {
>          devfn = VTD_SID_TO_DEVFN(source_id);
> -        for (devfn_it = 0; devfn_it < VTD_PCI_DEVFN_MAX; ++devfn_it) {
> +        for (devfn_it = 0; devfn_it < X86_IOMMU_PCI_DEVFN_MAX; ++devfn_it) {
>              vtd_as = vtd_bus->dev_as[devfn_it];
>              if (vtd_as && ((devfn_it & mask) == (devfn & mask))) {
>                  VTD_DPRINTF(INV, "invalidate context-cahce of devfn 0x%"PRIx16,
> @@ -1906,7 +1908,8 @@ VTDAddressSpace *vtd_find_add_as(IntelIOMMUState *s, PCIBus *bus, int devfn)
>  
>      if (!vtd_bus) {
>          /* No corresponding free() */
> -        vtd_bus = g_malloc0(sizeof(VTDBus) + sizeof(VTDAddressSpace *) * VTD_PCI_DEVFN_MAX);
> +        vtd_bus = g_malloc0(sizeof(VTDBus) + sizeof(VTDAddressSpace *) * \
> +                            X86_IOMMU_PCI_DEVFN_MAX);
>          vtd_bus->bus = bus;
>          key = (uintptr_t)bus;
>          g_hash_table_insert(s->vtd_as_by_busptr, &key, vtd_bus);
> diff --git a/hw/i386/x86-iommu.c b/hw/i386/x86-iommu.c
> index d739afb..f395139 100644
> --- a/hw/i386/x86-iommu.c
> +++ b/hw/i386/x86-iommu.c
> @@ -21,6 +21,28 @@
>  #include "hw/sysbus.h"
>  #include "hw/boards.h"
>  #include "hw/i386/x86-iommu.h"
> +#include "qemu/error-report.h"
> +
> +/* Default X86 IOMMU device */
> +static X86IOMMUState *x86_iommu_default = NULL;
> +
> +static void x86_iommu_set_default(X86IOMMUState *x86_iommu)
> +{
> +    assert(x86_iommu);
> +
> +    if (x86_iommu_default) {
> +        error_report("QEMU does not support multiple vIOMMUs "
> +                     "for x86 yet.");
> +        exit(1);
> +    }
> +
> +    x86_iommu_default = x86_iommu;
> +}
> +
> +X86IOMMUState *x86_iommu_get_default(void)
> +{
> +    return x86_iommu_default;
> +}
>  
>  static void x86_iommu_realize(DeviceState *dev, Error **errp)
>  {
> @@ -28,6 +50,7 @@ static void x86_iommu_realize(DeviceState *dev, Error **errp)
>      if (x86_class->realize) {
>          x86_class->realize(dev, errp);
>      }
> +    x86_iommu_set_default(X86_IOMMU_DEVICE(dev));
>  }
>  
>  static void x86_iommu_class_init(ObjectClass *klass, void *data)
> diff --git a/include/hw/i386/intel_iommu.h b/include/hw/i386/intel_iommu.h
> index 680a0c4..0794309 100644
> --- a/include/hw/i386/intel_iommu.h
> +++ b/include/hw/i386/intel_iommu.h
> @@ -35,7 +35,6 @@
>  #define VTD_PCI_BUS_MAX             256
>  #define VTD_PCI_SLOT_MAX            32
>  #define VTD_PCI_FUNC_MAX            8
> -#define VTD_PCI_DEVFN_MAX           256
>  #define VTD_PCI_SLOT(devfn)         (((devfn) >> 3) & 0x1f)
>  #define VTD_PCI_FUNC(devfn)         ((devfn) & 0x07)
>  #define VTD_SID_TO_BUS(sid)         (((sid) >> 8) & 0xff)
> diff --git a/include/hw/i386/x86-iommu.h b/include/hw/i386/x86-iommu.h
> index 924f39a..d6991cb 100644
> --- a/include/hw/i386/x86-iommu.h
> +++ b/include/hw/i386/x86-iommu.h
> @@ -30,6 +30,9 @@
>  #define  X86_IOMMU_GET_CLASS(obj) \
>      OBJECT_GET_CLASS(X86IOMMUClass, obj, TYPE_X86_IOMMU_DEVICE)
>  
> +#define X86_IOMMU_PCI_DEVFN_MAX           256
> +#define X86_IOMMU_SID_INVALID             (0xffff)
> +
>  typedef struct X86IOMMUState X86IOMMUState;
>  typedef struct X86IOMMUClass X86IOMMUClass;
>  
> @@ -43,4 +46,10 @@ struct X86IOMMUState {
>      SysBusDevice busdev;
>  };
>  
> +/**
> + * x86_iommu_get_default - get default IOMMU device
> + * @return: pointer to default IOMMU device
> + */
> +X86IOMMUState *x86_iommu_get_default(void);
> +
>  #endif
> -- 
> 2.4.11