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? 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 > > > >