Re: [PATCH v2 05/22] hw/pci: modify pci_setup_iommu() to set PCIIOMMUOps

[Auger Eric]

Hi Yi,

On 4/2/20 3:37 PM, Liu, Yi L wrote:
> Hi Eric,
> 
>> From: Auger Eric < address@hidden >
>> Sent: Thursday, April 2, 2020 8:41 PM
>> To: Liu, Yi L <address@hidden>; address@hidden;
>> Subject: Re: [PATCH v2 05/22] hw/pci: modify pci_setup_iommu() to set
>> PCIIOMMUOps
>>
>> Hi Yi,
>>
>> On 4/2/20 10:52 AM, Liu, Yi L wrote:
>>>> From: Auger Eric < address@hidden>
>>>> Sent: Monday, March 30, 2020 7:02 PM
>>>> To: Liu, Yi L <address@hidden>; address@hidden;
>>>> Subject: Re: [PATCH v2 05/22] hw/pci: modify pci_setup_iommu() to set
>>>> PCIIOMMUOps
>>>>
>>>>
>>>>
>>>> On 3/30/20 6:24 AM, Liu Yi L wrote:
>>>>> This patch modifies pci_setup_iommu() to set PCIIOMMUOps instead of
>>>>> setting PCIIOMMUFunc. PCIIOMMUFunc is used to get an address space
>>>>> for a PCI device in vendor specific way. The PCIIOMMUOps still
>>>>> offers this functionality. But using PCIIOMMUOps leaves space to add
>>>>> more iommu related vendor specific operations.
>>>>>
>>>>> Cc: Kevin Tian <address@hidden>
>>>>> Cc: Jacob Pan <address@hidden>
>>>>> Cc: Peter Xu <address@hidden>
>>>>> Cc: Eric Auger <address@hidden>
>>>>> Cc: Yi Sun <address@hidden>
>>>>> Cc: David Gibson <address@hidden>
>>>>> Cc: Michael S. Tsirkin <address@hidden>
>>>>> Reviewed-by: David Gibson <address@hidden>
>>>>> Reviewed-by: Peter Xu <address@hidden>
>>>>> Signed-off-by: Liu Yi L <address@hidden>
>>>>> ---
>>>>>  hw/alpha/typhoon.c       |  6 +++++-
>>>>>  hw/arm/smmu-common.c     |  6 +++++-
>>>>>  hw/hppa/dino.c           |  6 +++++-
>>>>>  hw/i386/amd_iommu.c      |  6 +++++-
>>>>>  hw/i386/intel_iommu.c    |  6 +++++-
>>>>>  hw/pci-host/designware.c |  6 +++++-
>>>>>  hw/pci-host/pnv_phb3.c   |  6 +++++-
>>>>>  hw/pci-host/pnv_phb4.c   |  6 +++++-
>>>>>  hw/pci-host/ppce500.c    |  6 +++++-
>>>>>  hw/pci-host/prep.c       |  6 +++++-
>>>>>  hw/pci-host/sabre.c      |  6 +++++-
>>>>>  hw/pci/pci.c             | 12 +++++++-----
>>>>>  hw/ppc/ppc440_pcix.c     |  6 +++++-
>>>>>  hw/ppc/spapr_pci.c       |  6 +++++-
>>>>>  hw/s390x/s390-pci-bus.c  |  8 ++++++--  hw/virtio/virtio-iommu.c |
>>>>> 6
>>>>> +++++-
>>>>>  include/hw/pci/pci.h     |  8 ++++++--
>>>>>  include/hw/pci/pci_bus.h |  2 +-
>>>>>  18 files changed, 90 insertions(+), 24 deletions(-)
>>>>>
>>>>> diff --git a/hw/alpha/typhoon.c b/hw/alpha/typhoon.c index
>>>>> 1795e2f..f271de1 100644
>>>>> --- a/hw/alpha/typhoon.c
>>>>> +++ b/hw/alpha/typhoon.c
>>>>> @@ -740,6 +740,10 @@ static AddressSpace
>>>>> *typhoon_pci_dma_iommu(PCIBus
>>>> *bus, void *opaque, int devfn)
>>>>>      return &s->pchip.iommu_as;
>>>>>  }
>>>>>
>>>>> +static const PCIIOMMUOps typhoon_iommu_ops = {
>>>>> +    .get_address_space = typhoon_pci_dma_iommu, };
>>>>> +
>>>>>  static void typhoon_set_irq(void *opaque, int irq, int level)  {
>>>>>      TyphoonState *s = opaque;
>>>>> @@ -897,7 +901,7 @@ PCIBus *typhoon_init(MemoryRegion *ram, ISABus
>>>> **isa_bus, qemu_irq *p_rtc_irq,
>>>>>                               "iommu-typhoon", UINT64_MAX);
>>>>>      address_space_init(&s->pchip.iommu_as, MEMORY_REGION(&s-
>>>>> pchip.iommu),
>>>>>                         "pchip0-pci");
>>>>> -    pci_setup_iommu(b, typhoon_pci_dma_iommu, s);
>>>>> +    pci_setup_iommu(b, &typhoon_iommu_ops, s);
>>>>>
>>>>>      /* Pchip0 PCI special/interrupt acknowledge, 0x801.F800.0000, 64MB.  
>>>>> */
>>>>>      memory_region_init_io(&s->pchip.reg_iack, OBJECT(s),
>>>>> &alpha_pci_iack_ops, diff --git a/hw/arm/smmu-common.c
>>>>> b/hw/arm/smmu-common.c index e13a5f4..447146e 100644
>>>>> --- a/hw/arm/smmu-common.c
>>>>> +++ b/hw/arm/smmu-common.c
>>>>> @@ -343,6 +343,10 @@ static AddressSpace *smmu_find_add_as(PCIBus
>>>>> *bus,
>>>> void *opaque, int devfn)
>>>>>      return &sdev->as;
>>>>>  }
>>>>>
>>>>> +static const PCIIOMMUOps smmu_ops = {
>>>>> +    .get_address_space = smmu_find_add_as, };
>>>>> +
>>>>>  IOMMUMemoryRegion *smmu_iommu_mr(SMMUState *s, uint32_t sid)  {
>>>>>      uint8_t bus_n, devfn;
>>>>> @@ -437,7 +441,7 @@ static void smmu_base_realize(DeviceState *dev,
>>>>> Error
>>>> **errp)
>>>>>      s->smmu_pcibus_by_busptr = g_hash_table_new(NULL, NULL);
>>>>>
>>>>>      if (s->primary_bus) {
>>>>> -        pci_setup_iommu(s->primary_bus, smmu_find_add_as, s);
>>>>> +        pci_setup_iommu(s->primary_bus, &smmu_ops, s);
>>>>>      } else {
>>>>>          error_setg(errp, "SMMU is not attached to any PCI bus!");
>>>>>      }
>>>>> diff --git a/hw/hppa/dino.c b/hw/hppa/dino.c index 2b1b38c..3da4f84
>>>>> 100644
>>>>> --- a/hw/hppa/dino.c
>>>>> +++ b/hw/hppa/dino.c
>>>>> @@ -459,6 +459,10 @@ static AddressSpace
>>>>> *dino_pcihost_set_iommu(PCIBus
>>>> *bus, void *opaque,
>>>>>      return &s->bm_as;
>>>>>  }
>>>>>
>>>>> +static const PCIIOMMUOps dino_iommu_ops = {
>>>>> +    .get_address_space = dino_pcihost_set_iommu, };
>>>>> +
>>>>>  /*
>>>>>   * Dino interrupts are connected as shown on Page 78, Table 23
>>>>>   * (Little-endian bit numbers)
>>>>> @@ -580,7 +584,7 @@ PCIBus *dino_init(MemoryRegion *addr_space,
>>>>>      memory_region_add_subregion(&s->bm, 0xfff00000,
>>>>>                                  &s->bm_cpu_alias);
>>>>>      address_space_init(&s->bm_as, &s->bm, "pci-bm");
>>>>> -    pci_setup_iommu(b, dino_pcihost_set_iommu, s);
>>>>> +    pci_setup_iommu(b, &dino_iommu_ops, s);
>>>>>
>>>>>      *p_rtc_irq = qemu_allocate_irq(dino_set_timer_irq, s, 0);
>>>>>      *p_ser_irq = qemu_allocate_irq(dino_set_serial_irq, s, 0); diff
>>>>> --git a/hw/i386/amd_iommu.c b/hw/i386/amd_iommu.c index
>>>>> b1175e5..5fec30e 100644
>>>>> --- a/hw/i386/amd_iommu.c
>>>>> +++ b/hw/i386/amd_iommu.c
>>>>> @@ -1451,6 +1451,10 @@ static AddressSpace
>>>> *amdvi_host_dma_iommu(PCIBus *bus, void *opaque, int devfn)
>>>>>      return &iommu_as[devfn]->as;
>>>>>  }
>>>>>
>>>>> +static const PCIIOMMUOps amdvi_iommu_ops = {
>>>>> +    .get_address_space = amdvi_host_dma_iommu, };
>>>>> +
>>>>>  static const MemoryRegionOps mmio_mem_ops = {
>>>>>      .read = amdvi_mmio_read,
>>>>>      .write = amdvi_mmio_write,
>>>>> @@ -1577,7 +1581,7 @@ static void amdvi_realize(DeviceState *dev,
>>>>> Error **errp)
>>>>>
>>>>>      sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->mmio);
>>>>>      sysbus_mmio_map(SYS_BUS_DEVICE(s), 0, AMDVI_BASE_ADDR);
>>>>> -    pci_setup_iommu(bus, amdvi_host_dma_iommu, s);
>>>>> +    pci_setup_iommu(bus, &amdvi_iommu_ops, s);
>>>>>      s->devid = object_property_get_int(OBJECT(&s->pci), "addr", errp);
>>>>>      msi_init(&s->pci.dev, 0, 1, true, false, errp);
>>>>>      amdvi_init(s);
>>>>> diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c index
>>>>> df7ad25..4b22910 100644
>>>>> --- a/hw/i386/intel_iommu.c
>>>>> +++ b/hw/i386/intel_iommu.c
>>>>> @@ -3729,6 +3729,10 @@ static AddressSpace
>>>>> *vtd_host_dma_iommu(PCIBus
>>>> *bus, void *opaque, int devfn)
>>>>>      return &vtd_as->as;
>>>>>  }
>>>>>
>>>>> +static PCIIOMMUOps vtd_iommu_ops = {
>>>> static const
>>>
>>> got it.
>>>
>>>>> +    .get_address_space = vtd_host_dma_iommu, };
>>>>> +
>>>>>  static bool vtd_decide_config(IntelIOMMUState *s, Error **errp)  {
>>>>>      X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(s); @@ -3840,7
>>>>> +3844,7 @@ static void vtd_realize(DeviceState *dev, Error **errp)
>>>>>                                                g_free, g_free);
>>>>>      vtd_init(s);
>>>>>      sysbus_mmio_map(SYS_BUS_DEVICE(s), 0,
>>>> Q35_HOST_BRIDGE_IOMMU_ADDR);
>>>>> -    pci_setup_iommu(bus, vtd_host_dma_iommu, dev);
>>>>> +    pci_setup_iommu(bus, &vtd_iommu_ops, dev);
>>>>>      /* Pseudo address space under root PCI bus. */
>>>>>      x86ms->ioapic_as = vtd_host_dma_iommu(bus, s,
>>>> Q35_PSEUDO_DEVFN_IOAPIC);
>>>>>      qemu_add_machine_init_done_notifier(&vtd_machine_done_notify);
>>>>> diff --git a/hw/pci-host/designware.c b/hw/pci-host/designware.c
>>>>> index dd24551..4c6338a 100644
>>>>> --- a/hw/pci-host/designware.c
>>>>> +++ b/hw/pci-host/designware.c
>>>>> @@ -645,6 +645,10 @@ static AddressSpace
>>>> *designware_pcie_host_set_iommu(PCIBus *bus, void *opaque,
>>>>>      return &s->pci.address_space;
>>>>>  }
>>>>>
>>>>> +static const PCIIOMMUOps designware_iommu_ops = {
>>>>> +    .get_address_space = designware_pcie_host_set_iommu, };
>>>>> +
>>>>>  static void designware_pcie_host_realize(DeviceState *dev, Error
>>>>> **errp)  {
>>>>>      PCIHostState *pci = PCI_HOST_BRIDGE(dev); @@ -686,7 +690,7 @@
>>>>> static void designware_pcie_host_realize(DeviceState *dev, Error **errp)
>>>>>      address_space_init(&s->pci.address_space,
>>>>>                         &s->pci.address_space_root,
>>>>>                         "pcie-bus-address-space");
>>>>> -    pci_setup_iommu(pci->bus, designware_pcie_host_set_iommu, s);
>>>>> +    pci_setup_iommu(pci->bus, &designware_iommu_ops, s);
>>>>>
>>>>>      qdev_set_parent_bus(DEVICE(&s->root), BUS(pci->bus));
>>>>>      qdev_init_nofail(DEVICE(&s->root));
>>>>> diff --git a/hw/pci-host/pnv_phb3.c b/hw/pci-host/pnv_phb3.c index
>>>>> 74618fa..ecfe627 100644
>>>>> --- a/hw/pci-host/pnv_phb3.c
>>>>> +++ b/hw/pci-host/pnv_phb3.c
>>>>> @@ -961,6 +961,10 @@ static AddressSpace *pnv_phb3_dma_iommu(PCIBus
>>>> *bus, void *opaque, int devfn)
>>>>>      return &ds->dma_as;
>>>>>  }
>>>>>
>>>>> +static PCIIOMMUOps pnv_phb3_iommu_ops = {
>>>> static const
>>> got it. :-)
>>>
>>>>> +    .get_address_space = pnv_phb3_dma_iommu, };
>>>>> +
>>>>>  static void pnv_phb3_instance_init(Object *obj)  {
>>>>>      PnvPHB3 *phb = PNV_PHB3(obj);
>>>>> @@ -1059,7 +1063,7 @@ static void pnv_phb3_realize(DeviceState *dev,
>>>>> Error
>>>> **errp)
>>>>>                                       &phb->pci_mmio, &phb->pci_io,
>>>>>                                       0, 4, TYPE_PNV_PHB3_ROOT_BUS);
>>>>>
>>>>> -    pci_setup_iommu(pci->bus, pnv_phb3_dma_iommu, phb);
>>>>> +    pci_setup_iommu(pci->bus, &pnv_phb3_iommu_ops, phb);
>>>>>
>>>>>      /* Add a single Root port */
>>>>>      qdev_prop_set_uint8(DEVICE(&phb->root), "chassis",
>>>>> phb->chip_id); diff --git a/hw/pci-host/pnv_phb4.c
>>>>> b/hw/pci-host/pnv_phb4.c index
>>>>> 23cf093..04e95e3 100644
>>>>> --- a/hw/pci-host/pnv_phb4.c
>>>>> +++ b/hw/pci-host/pnv_phb4.c
>>>>> @@ -1148,6 +1148,10 @@ static AddressSpace
>>>>> *pnv_phb4_dma_iommu(PCIBus
>>>> *bus, void *opaque, int devfn)
>>>>>      return &ds->dma_as;
>>>>>  }
>>>>>
>>>>> +static PCIIOMMUOps pnv_phb4_iommu_ops = {
>>>> idem
>>> will add const.
>>>
>>>>> +    .get_address_space = pnv_phb4_dma_iommu, };
>>>>> +
>>>>>  static void pnv_phb4_instance_init(Object *obj)  {
>>>>>      PnvPHB4 *phb = PNV_PHB4(obj);
>>>>> @@ -1205,7 +1209,7 @@ static void pnv_phb4_realize(DeviceState *dev,
>>>>> Error
>>>> **errp)
>>>>>                                       pnv_phb4_set_irq, pnv_phb4_map_irq, 
>>>>> phb,
>>>>>                                       &phb->pci_mmio, &phb->pci_io,
>>>>>                                       0, 4, TYPE_PNV_PHB4_ROOT_BUS);
>>>>> -    pci_setup_iommu(pci->bus, pnv_phb4_dma_iommu, phb);
>>>>> +    pci_setup_iommu(pci->bus, &pnv_phb4_iommu_ops, phb);
>>>>>
>>>>>      /* Add a single Root port */
>>>>>      qdev_prop_set_uint8(DEVICE(&phb->root), "chassis",
>>>>> phb->chip_id); diff --git a/hw/pci-host/ppce500.c
>>>>> b/hw/pci-host/ppce500.c index d710727..5baf5db 100644
>>>>> --- a/hw/pci-host/ppce500.c
>>>>> +++ b/hw/pci-host/ppce500.c
>>>>> @@ -439,6 +439,10 @@ static AddressSpace
>>>>> *e500_pcihost_set_iommu(PCIBus
>>>> *bus, void *opaque,
>>>>>      return &s->bm_as;
>>>>>  }
>>>>>
>>>>> +static const PCIIOMMUOps ppce500_iommu_ops = {
>>>>> +    .get_address_space = e500_pcihost_set_iommu, };
>>>>> +
>>>>>  static void e500_pcihost_realize(DeviceState *dev, Error **errp)  {
>>>>>      SysBusDevice *sbd = SYS_BUS_DEVICE(dev); @@ -473,7 +477,7 @@
>>>>> static void e500_pcihost_realize(DeviceState *dev, Error **errp)
>>>>>      memory_region_init(&s->bm, OBJECT(s), "bm-e500", UINT64_MAX);
>>>>>      memory_region_add_subregion(&s->bm, 0x0, &s->busmem);
>>>>>      address_space_init(&s->bm_as, &s->bm, "pci-bm");
>>>>> -    pci_setup_iommu(b, e500_pcihost_set_iommu, s);
>>>>> +    pci_setup_iommu(b, &ppce500_iommu_ops, s);
>>>>>
>>>>>      pci_create_simple(b, 0, "e500-host-bridge");
>>>>>
>>>>> diff --git a/hw/pci-host/prep.c b/hw/pci-host/prep.c index
>>>>> 1a02e9a..7c57311 100644
>>>>> --- a/hw/pci-host/prep.c
>>>>> +++ b/hw/pci-host/prep.c
>>>>> @@ -213,6 +213,10 @@ static AddressSpace
>>>>> *raven_pcihost_set_iommu(PCIBus
>>>> *bus, void *opaque,
>>>>>      return &s->bm_as;
>>>>>  }
>>>>>
>>>>> +static const PCIIOMMUOps raven_iommu_ops = {
>>>>> +    .get_address_space = raven_pcihost_set_iommu, };
>>>>> +
>>>>>  static void raven_change_gpio(void *opaque, int n, int level)  {
>>>>>      PREPPCIState *s = opaque;
>>>>> @@ -303,7 +307,7 @@ static void raven_pcihost_initfn(Object *obj)
>>>>>      memory_region_add_subregion(&s->bm, 0         , &s-
>>> bm_pci_memory_alias);
>>>>>      memory_region_add_subregion(&s->bm, 0x80000000, &s->bm_ram_alias);
>>>>>      address_space_init(&s->bm_as, &s->bm, "raven-bm");
>>>>> -    pci_setup_iommu(&s->pci_bus, raven_pcihost_set_iommu, s);
>>>>> +    pci_setup_iommu(&s->pci_bus, &raven_iommu_ops, s);
>>>>>
>>>>>      h->bus = &s->pci_bus;
>>>>>
>>>>> diff --git a/hw/pci-host/sabre.c b/hw/pci-host/sabre.c index
>>>>> 2b8503b..251549b 100644
>>>>> --- a/hw/pci-host/sabre.c
>>>>> +++ b/hw/pci-host/sabre.c
>>>>> @@ -112,6 +112,10 @@ static AddressSpace *sabre_pci_dma_iommu(PCIBus
>>>> *bus, void *opaque, int devfn)
>>>>>      return &is->iommu_as;
>>>>>  }
>>>>>
>>>>> +static const PCIIOMMUOps sabre_iommu_ops = {
>>>>> +    .get_address_space = sabre_pci_dma_iommu, };
>>>>> +
>>>>>  static void sabre_config_write(void *opaque, hwaddr addr,
>>>>>                                 uint64_t val, unsigned size)  { @@
>>>>> -402,7 +406,7 @@ static void sabre_realize(DeviceState *dev, Error **errp)
>>>>>      /* IOMMU */
>>>>>      memory_region_add_subregion_overlap(&s->sabre_config, 0x200,
>>>>>                      sysbus_mmio_get_region(SYS_BUS_DEVICE(s->iommu), 0), 
>>>>> 1);
>>>>> -    pci_setup_iommu(phb->bus, sabre_pci_dma_iommu, s->iommu);
>>>>> +    pci_setup_iommu(phb->bus, &sabre_iommu_ops, s->iommu);
>>>>>
>>>>>      /* APB secondary busses */
>>>>>      pci_dev = pci_create_multifunction(phb->bus, PCI_DEVFN(1, 0),
>>>>> true, diff --git a/hw/pci/pci.c b/hw/pci/pci.c index
>>>>> e1ed667..aa9025c
>>>>> 100644
>>>>> --- a/hw/pci/pci.c
>>>>> +++ b/hw/pci/pci.c
>>>>> @@ -2644,7 +2644,7 @@ AddressSpace
>>>> *pci_device_iommu_address_space(PCIDevice *dev)
>>>>>      PCIBus *iommu_bus = bus;
>>>>>      uint8_t devfn = dev->devfn;
>>>>>
>>>>> -    while (iommu_bus && !iommu_bus->iommu_fn && iommu_bus-
>>> parent_dev)
>>>> {
>>>>> +    while (iommu_bus && !iommu_bus->iommu_ops &&
>>>>> + iommu_bus->parent_dev) {
>>>> Depending on future usage, this is not strictly identical to the
>>>> original code. You exit the loop as soon as a iommu_bus->iommu_ops is
>>>> set whatever the presence of get_address_space().
>>>
>>> To be identical with original code, may adding the get_address_space()
>>> presence check. Then the loop exits when the iommu_bus->iommu_ops is
>>> set and meanwhile iommu_bus->iommu_ops->get_address_space() is set.
>>> But is it possible that there is an intermediate iommu_bus which has
>>> iommu_ops set but the get_address_space() is clear. I guess not as
>>> iommu_ops is set by vIOMMU and vIOMMU won't differentiate buses?
>>
>> I don't know. That depends on how the ops are going to be used in the 
>> future. Can't
>> you enforce the fact that get_address_space() is a mandatory ops?
> 
> No, I didn't mean that. Actually, in the patch, the get_address_space() 
> presence is checked.
> I'm not sure if your point is to add get_address_space() presence check 
> instead of
> just checking the iommu_ops presence.
Yes that was my point. I wanted to underline the checks are not strictly
identical and maybe during enumeration you may find a device with ops
set and no get_address_space(). Then I meant maybe you should enforce
somewhere in the code or in the documentation that get_address_space()
is a mandatory operation in the ops struct and must be set as soon as
the struct is passed. maybe in pci_setup_iommu() you could check that
get_address_space is set?

Thanks

Eric
> 
> Regards,
> Yi Liu
>