Hi Markus On 6/26/20 10:53 AM, Markus Armbruster wrote: > Auger Eric <[email protected]> writes: > >> Hi Markus, >> On 6/25/20 9:05 AM, Markus Armbruster wrote: >>> Eric Auger <[email protected]> writes: >>> >>>> This patch implements the PROBE request. At the moment, >>>> only THE RESV_MEM property is handled. The first goal is >>>> to report iommu wide reserved regions such as the MSI regions >>>> set by the machine code. On x86 this will be the IOAPIC MSI >>>> region, [0xFEE00000 - 0xFEEFFFFF], on ARM this may be the ITS >>>> doorbell. >>>> >>>> In the future we may introduce per device reserved regions. >>>> This will be useful when protecting host assigned devices >>>> which may expose their own reserved regions >>>> >>>> Signed-off-by: Eric Auger <[email protected]> >>>> Reviewed-by: Jean-Philippe Brucker <[email protected]> >>>> >>>> --- >>>> >>>> v4 -> v5: >>>> - assert if reserved region type is different from RESERVED or >>>> MSI >>>> >>>> v3 -> v4: >>>> - removed any reference to the NONE property that does not >>>> exist anymore. >>>> >>>> v2 -> v3: >>>> - on probe, do not fill the reminder of the buffer with zeroes >>>> as the buffer was already zero initialized (Bharat) >>>> >>>> v1 -> v2: >>>> - move the unlock back to the same place >>>> - remove the push label and factorize the code after the out label >>>> - fix a bunch of cpu_to_leX according to the latest spec revision >>>> - do not remove sizeof(last) from free space >>>> - check the ep exists >>>> --- >>>> include/hw/virtio/virtio-iommu.h | 2 + >>>> hw/virtio/virtio-iommu.c | 92 ++++++++++++++++++++++++++++++-- >>>> hw/virtio/trace-events | 1 + >>>> 3 files changed, 91 insertions(+), 4 deletions(-) >>>> >>>> diff --git a/include/hw/virtio/virtio-iommu.h >>>> b/include/hw/virtio/virtio-iommu.h >>>> index e653004d7c..49eb105cd8 100644 >>>> --- a/include/hw/virtio/virtio-iommu.h >>>> +++ b/include/hw/virtio/virtio-iommu.h >>>> @@ -53,6 +53,8 @@ typedef struct VirtIOIOMMU { >>>> GHashTable *as_by_busptr; >>>> IOMMUPciBus *iommu_pcibus_by_bus_num[PCI_BUS_MAX]; >>>> PCIBus *primary_bus; >>>> + ReservedRegion *reserved_regions; >>>> + uint32_t nb_reserved_regions; >>>> GTree *domains; >>>> QemuMutex mutex; >>>> GTree *endpoints; >>>> diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c >>>> index 483883ec1d..aabc3e36b1 100644 >>>> --- a/hw/virtio/virtio-iommu.c >>>> +++ b/hw/virtio/virtio-iommu.c >>>> @@ -38,6 +38,7 @@ >>>> >>>> /* Max size */ >>>> #define VIOMMU_DEFAULT_QUEUE_SIZE 256 >>>> +#define VIOMMU_PROBE_SIZE 512 >>>> >>>> typedef struct VirtIOIOMMUDomain { >>>> uint32_t id; >>>> @@ -378,6 +379,63 @@ static int virtio_iommu_unmap(VirtIOIOMMU *s, >>>> return ret; >>>> } >>>> >>>> +static ssize_t virtio_iommu_fill_resv_mem_prop(VirtIOIOMMU *s, uint32_t >>>> ep, >>>> + uint8_t *buf, size_t free) >>>> +{ >>>> + struct virtio_iommu_probe_resv_mem prop = {}; >>>> + size_t size = sizeof(prop), length = size - sizeof(prop.head), total; >>>> + int i; >>>> + >>>> + total = size * s->nb_reserved_regions; >>>> + >>>> + if (total > free) { >>>> + return -ENOSPC; >>>> + } >>>> + >>>> + for (i = 0; i < s->nb_reserved_regions; i++) { >>>> + prop.head.type = cpu_to_le16(VIRTIO_IOMMU_PROBE_T_RESV_MEM); >>>> + prop.head.length = cpu_to_le16(length); >>>> + prop.subtype = s->reserved_regions[i].type; >>>> + assert(prop.subtype == VIRTIO_IOMMU_RESV_MEM_T_RESERVED || >>>> + prop.subtype == VIRTIO_IOMMU_RESV_MEM_T_MSI); >>> >>> The assertion makes sense here: we're mapping from the generic >>> ReservedRegion type (which is unsigned) to the specific >>> virtio_iommu_probe_resv_mem subtype (which is uint8_t, but only these >>> two values are valid). >>> >>> Howver, the assertion should test s->reserved_regions[i].type and go >>> before the assignment, to ensure it doesn't truncate! >> OK I will do. >>> >>> Can I trigger the assertion with -device? My try to find the answer >>> myself failed: >> At the moment the virtio-iommu-pci device only can be instantiated with >> machvirt, booting in dt mode. > > I asked because if I can, then invalid types need to be rejected > cleanly. > > Invalid property values can be rejected by the setter, or by the realize > method. Since this setter by design accepts anything that fits into > unsigned, it's realize.
OK. Then the place where I do the assert is not the right one as this will happen later. Probe request is triggered by the guest virtio-iommu driver. Thanks Eric > > [...] >
