Hi Eric, > -----Original Message----- > From: Auger Eric <eric.au...@redhat.com> > Sent: Tuesday, May 12, 2020 8:39 AM > To: Bharat Bhushan <bbhush...@marvell.com>; eric.auger....@gmail.com; > qemu-devel@nongnu.org; qemu-...@nongnu.org; peter.mayd...@linaro.org; > m...@redhat.com; jean-phili...@linaro.org; pet...@redhat.com; > arm...@redhat.com; pbonz...@redhat.com > Subject: Re: [EXT] [PATCH v2 2/5] virtio-iommu: Implement RESV_MEM probe > request > > Hi Bharat, > On 5/12/20 5:03 AM, Bharat Bhushan wrote: > > Hi Eric, > > > >> -----Original Message----- > >> From: Auger Eric <eric.au...@redhat.com> > >> Sent: Monday, May 11, 2020 2:19 PM > >> To: Bharat Bhushan <bbhush...@marvell.com>; eric.auger....@gmail.com; > >> qemu-devel@nongnu.org; qemu-...@nongnu.org; peter.mayd...@linaro.org; > >> m...@redhat.com; jean-phili...@linaro.org; pet...@redhat.com; > >> arm...@redhat.com; pbonz...@redhat.com > >> Subject: Re: [EXT] [PATCH v2 2/5] virtio-iommu: Implement RESV_MEM > >> probe request > >> > >> Hi Bharat, > >> > >> On 5/11/20 10:42 AM, Bharat Bhushan wrote: > >>> Hi Eric, > >>> > >>>> -----Original Message----- > >>>> From: Auger Eric <eric.au...@redhat.com> > >>>> Sent: Monday, May 11, 2020 12:26 PM > >>>> To: Bharat Bhushan <bbhush...@marvell.com>; > >>>> eric.auger....@gmail.com; qemu-devel@nongnu.org; > >>>> qemu-...@nongnu.org; peter.mayd...@linaro.org; m...@redhat.com; > >>>> jean-phili...@linaro.org; pet...@redhat.com; arm...@redhat.com; > >>>> pbonz...@redhat.com > >>>> Subject: Re: [EXT] [PATCH v2 2/5] virtio-iommu: Implement RESV_MEM > >>>> probe request > >>>> > >>>> Hi Bharat, > >>>> On 5/11/20 8:38 AM, Bharat Bhushan wrote: > >>>>> Hi Eric, > >>>>> > >>>>>> -----Original Message----- > >>>>>> From: Eric Auger <eric.au...@redhat.com> > >>>>>> Sent: Friday, May 8, 2020 11:01 PM > >>>>>> To: eric.auger....@gmail.com; eric.au...@redhat.com; > >>>>>> qemu-devel@nongnu.org; qemu-...@nongnu.org; > >>>>>> peter.mayd...@linaro.org; m...@redhat.com; jean- > >>>>>> phili...@linaro.org; Bharat Bhushan <bbhush...@marvell.com>; > >>>>>> pet...@redhat.com; arm...@redhat.com; pbonz...@redhat.com > >>>>>> Subject: [EXT] [PATCH v2 2/5] virtio-iommu: Implement RESV_MEM > >>>>>> probe request > >>>>>> > >>>>>> External Email > >>>>>> > >>>>>> ----------------------------------------------------------------- > >>>>>> -- > >>>>>> -- > >>>>>> - 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 <eric.au...@redhat.com> > >>>>>> > >>>>>> --- > >>>>>> > >>>>>> 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 | 94 ++++++++++++++++++++++++++++++-- > >>>>>> hw/virtio/trace-events | 1 + > >>>>>> 3 files changed, 93 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 > >>>>>> 22ba8848c2..35d772e021 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 +379,65 @@ 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; > >>>>>> + prop.start = cpu_to_le64(s->reserved_regions[i].low); > >>>>>> + prop.end = cpu_to_le64(s->reserved_regions[i].high); > >>>>>> + > >>>>>> + memcpy(buf, &prop, size); > >>>>>> + > >>>>>> + trace_virtio_iommu_fill_resv_property(ep, prop.subtype, > >>>>>> + prop.start, prop.end); > >>>>>> + buf += size; > >>>>>> + } > >>>>>> + return total; > >>>>>> +} > >>>>>> + > >>>>>> +/** > >>>>>> + * virtio_iommu_probe - Fill the probe request buffer with > >>>>>> + * the properties the device is able to return and add a NONE > >>>>>> + * property at the end. > >>>>>> + */ > >>>>>> +static int virtio_iommu_probe(VirtIOIOMMU *s, > >>>>>> + struct virtio_iommu_req_probe *req, > >>>>>> + uint8_t *buf) { > >>>>>> + uint32_t ep_id = le32_to_cpu(req->endpoint); > >>>>>> + size_t free = VIOMMU_PROBE_SIZE; > >>>>>> + ssize_t count; > >>>>>> + > >>>>>> + if (!virtio_iommu_mr(s, ep_id)) { > >>>>>> + return VIRTIO_IOMMU_S_NOENT; > >>>>>> + } > >>>>>> + > >>>>>> + count = virtio_iommu_fill_resv_mem_prop(s, ep_id, buf, free); > >>>>>> + if (count < 0) { > >>>>>> + return VIRTIO_IOMMU_S_INVAL; > >>>>>> + } > >>>>>> + buf += count; > >>>>>> + free -= count; > >>>>>> + > >>>>>> + /* Fill the rest with zeroes */ > >>>>>> + memset(buf, 0, free); > >>>>> > >>>>> No need to fill with zero here as "buf" is set to zero on allocation, > >>>>> no? > >>>> > >>>> You're right. I will remove this in the next version. > >>>> > >>>> Thanks > >>>> > >>>> Eric > >>>>> > >>>>> Thanks > >>>>> -Bharat > >>>>> > >>>>>> + > >>>>>> + return VIRTIO_IOMMU_S_OK; > >>>>>> +} > >>>>>> + > >>>>>> static int virtio_iommu_iov_to_req(struct iovec *iov, > >>>>>> unsigned int iov_cnt, > >>>>>> void *req, size_t req_sz) @@ > >>>>>> -407,15 +467,27 @@ > >>>>>> virtio_iommu_handle_req(detach) > >>>>>> virtio_iommu_handle_req(map) > >>>>>> virtio_iommu_handle_req(unmap) > >>>>>> > >>>>>> +static int virtio_iommu_handle_probe(VirtIOIOMMU *s, > >>>>>> + struct iovec *iov, > >>>>>> + unsigned int iov_cnt, > >>>>>> + uint8_t *buf) { > >>>>>> + struct virtio_iommu_req_probe req; > >>>>>> + int ret = virtio_iommu_iov_to_req(iov, iov_cnt, &req, > >>>>>> +sizeof(req)); > >>>>>> + > >>>>>> + return ret ? ret : virtio_iommu_probe(s, &req, buf); } > >>>>>> + > >>>>>> static void virtio_iommu_handle_command(VirtIODevice *vdev, > >>>>>> VirtQueue > >>>> *vq) { > >>>>>> VirtIOIOMMU *s = VIRTIO_IOMMU(vdev); > >>>>>> struct virtio_iommu_req_head head; > >>>>>> struct virtio_iommu_req_tail tail = {}; > >>>>>> + size_t output_size = sizeof(tail), sz; > >>>>>> VirtQueueElement *elem; > >>>>>> unsigned int iov_cnt; > >>>>>> struct iovec *iov; > >>>>>> - size_t sz; > >>>>>> + void *buf = NULL; > >>>>>> > >>>>>> for (;;) { > >>>>>> elem = virtqueue_pop(vq, sizeof(VirtQueueElement)); @@ > >>>>>> -452,6 +524,17 @@ static void > >>>>>> virtio_iommu_handle_command(VirtIODevice > >>>> *vdev, VirtQueue *vq) > >>>>>> case VIRTIO_IOMMU_T_UNMAP: > >>>>>> tail.status = virtio_iommu_handle_unmap(s, iov, iov_cnt); > >>>>>> break; > >>>>>> + case VIRTIO_IOMMU_T_PROBE: > >>> > >>> As per spec > >>> " > >>> If the device does not offer the VIRTIO_IOMMU_F_PROBE feature, > >>> and if the > >> driver sends a VIRTIO_- > >>> IOMMU_T_PROBE request, then the device SHOULD NOT write the > >>> buffer and > >> SHOULD set the used > >>> length to zero. > >>> " > >>> So we should check if device supports "VIRTIO_IOMMU_F_PROBE" before > >> proceed? > >> But are the device and from that patch onwards we do support the > >> VIRTIO_IOMMU_F_PROBE feature, right? > > > > Yes I agree, do you think if for debugging one wants to try out without this > feature then he should just disable VIRTIO_IOMMU_F_PROBE. > > You mean for debugging the driver? I don't think this is the purpose of this > device.
Yes for debugging purpose only. Thanks -Bharat > > Thanks > > Eric > > > > Thanks > > -Bharat > > > >> > >> Thanks > >> > >> Eric > >>> > >>> Thanks > >>> -Bharat > >>> > >>>>>> + { > >>>>>> + struct virtio_iommu_req_tail *ptail; > >>>>>> + > >>>>>> + output_size = s->config.probe_size + sizeof(tail); > >>>>>> + buf = g_malloc0(output_size); > >>>>>> + > >>>>>> + ptail = (struct virtio_iommu_req_tail *) > >>>>>> + (buf + s->config.probe_size); > >>>>>> + ptail->status = virtio_iommu_handle_probe(s, iov, > >>>>>> iov_cnt, buf); > >>>>>> + } > >>>>>> default: > >>>>>> tail.status = VIRTIO_IOMMU_S_UNSUPP; > >>>>>> } > >>>>>> @@ -459,12 +542,13 @@ static void > >>>>>> virtio_iommu_handle_command(VirtIODevice *vdev, VirtQueue *vq) > >>>>>> > >>>>>> out: > >>>>>> sz = iov_from_buf(elem->in_sg, elem->in_num, 0, > >>>>>> - &tail, sizeof(tail)); > >>>>>> - assert(sz == sizeof(tail)); > >>>>>> + buf ? buf : &tail, output_size); > >>>>>> + assert(sz == output_size); > >>>>>> > >>>>>> - virtqueue_push(vq, elem, sizeof(tail)); > >>>>>> + virtqueue_push(vq, elem, sz); > >>>>>> virtio_notify(vdev, vq); > >>>>>> g_free(elem); > >>>>>> + g_free(buf); > >>>>>> } > >>>>>> } > >>>>>> > >>>>>> @@ -667,6 +751,7 @@ static void > >>>>>> virtio_iommu_device_realize(DeviceState *dev, Error **errp) > >>>>>> s->config.page_size_mask = TARGET_PAGE_MASK; > >>>>>> s->config.input_range.end = -1UL; > >>>>>> s->config.domain_range.end = 32; > >>>>>> + s->config.probe_size = VIOMMU_PROBE_SIZE; > >>>>>> > >>>>>> virtio_add_feature(&s->features, VIRTIO_RING_F_EVENT_IDX); > >>>>>> virtio_add_feature(&s->features, > >>>>>> VIRTIO_RING_F_INDIRECT_DESC); @@ -676,6 > >>>>>> +761,7 @@ static void virtio_iommu_device_realize(DeviceState > >>>>>> +*dev, Error > >>>>>> **errp) > >>>>>> virtio_add_feature(&s->features, VIRTIO_IOMMU_F_MAP_UNMAP); > >>>>>> virtio_add_feature(&s->features, VIRTIO_IOMMU_F_BYPASS); > >>>>>> virtio_add_feature(&s->features, VIRTIO_IOMMU_F_MMIO); > >>>>>> + virtio_add_feature(&s->features, VIRTIO_IOMMU_F_PROBE); > >>>>>> > >>>>>> qemu_mutex_init(&s->mutex); > >>>>>> > >>>>>> diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events > >>>>>> index > >>>>>> e83500bee9..5550475691 100644 > >>>>>> --- a/hw/virtio/trace-events > >>>>>> +++ b/hw/virtio/trace-events > >>>>>> @@ -73,3 +73,4 @@ virtio_iommu_get_domain(uint32_t domain_id) > >>>>>> "Alloc domain=%d" > >>>>>> virtio_iommu_put_domain(uint32_t domain_id) "Free domain=%d" > >>>>>> virtio_iommu_translate_out(uint64_t virt_addr, uint64_t > >>>>>> phys_addr, uint32_t sid) "0x%"PRIx64" -> 0x%"PRIx64 " for sid=%d" > >>>>>> virtio_iommu_report_fault(uint8_t reason, uint32_t flags, > >>>>>> uint32_t endpoint, uint64_t addr) "FAULT reason=%d flags=%d > >>>>>> endpoint=%d address =0x%"PRIx64 > >>>>>> +virtio_iommu_fill_resv_property(uint32_t devid, uint8_t subtype, > >>>>>> +uint64_t start, uint64_t end) "dev= %d, type=%d start=0x%"PRIx64" > >>>>>> +end=0x%"PRIx64 > >>>>>> -- > >>>>>> 2.20.1 > >>>>> > >>>>> > >>> > >