Re: [PATCH v7 2/5] virtio-iommu: Add iommu notifier for map/unmap

[Bharat Bhushan]

Hi Eric,

On Fri, Mar 13, 2020 at 7:55 PM Auger Eric <address@hidden> wrote:
>
> Hi Bharat,
> On 3/13/20 8:48 AM, Bharat Bhushan wrote:
> > This patch extends VIRTIO_IOMMU_T_MAP/UNMAP request to
> > notify registered iommu-notifier. Which will call vfio
> s/iommu-notifier/iommu-notifiers
> > notifier to map/unmap region in iommu.
> can be any notifier (vhost/vfio).
> >
> > Signed-off-by: Bharat Bhushan <address@hidden>
> > Signed-off-by: Eric Auger <address@hidden>
> > ---
> >  hw/virtio/trace-events           |  2 +
> >  hw/virtio/virtio-iommu.c         | 66 +++++++++++++++++++++++++++++++-
> >  include/hw/virtio/virtio-iommu.h |  6 +++
> >  3 files changed, 73 insertions(+), 1 deletion(-)
> >
> > diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
> > index e83500bee9..d94a1cd8a3 100644
> > --- a/hw/virtio/trace-events
> > +++ b/hw/virtio/trace-events
> > @@ -73,3 +73,5 @@ 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_notify_map(const char *name, uint64_t iova, uint64_t paddr, 
> > uint64_t map_size) "mr=%s iova=0x%"PRIx64" pa=0x%" PRIx64" size=0x%"PRIx64
> > +virtio_iommu_notify_unmap(const char *name, uint64_t iova, uint64_t 
> > map_size) "mr=%s iova=0x%"PRIx64" size=0x%"PRIx64
> > diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
> > index 4cee8083bc..e51344a53e 100644
> > --- a/hw/virtio/virtio-iommu.c
> > +++ b/hw/virtio/virtio-iommu.c
> > @@ -123,6 +123,38 @@ static gint interval_cmp(gconstpointer a, 
> > gconstpointer b, gpointer user_data)
> >      }
> >  }
> >
> > +static void virtio_iommu_notify_map(IOMMUMemoryRegion *mr, hwaddr iova,
> > +                                    hwaddr paddr, hwaddr size)
> > +{
> > +    IOMMUTLBEntry entry;
> > +
> > +    entry.target_as = &address_space_memory;
> > +    entry.addr_mask = size - 1;
> > +
> > +    entry.iova = iova;
> > +    trace_virtio_iommu_notify_map(mr->parent_obj.name, iova, paddr, size);
> > +    entry.perm = IOMMU_RW;
> > +    entry.translated_addr = paddr;
> > +
> > +    memory_region_notify_iommu(mr, 0, entry);
> > +}
> > +
> > +static void virtio_iommu_notify_unmap(IOMMUMemoryRegion *mr, hwaddr iova,
> > +                                      hwaddr size)
> > +{
> > +    IOMMUTLBEntry entry;
> > +
> > +    entry.target_as = &address_space_memory;
> > +    entry.addr_mask = size - 1;
> > +
> > +    entry.iova = iova;
> > +    trace_virtio_iommu_notify_unmap(mr->parent_obj.name, iova, size);
> > +    entry.perm = IOMMU_NONE;
> > +    entry.translated_addr = 0;
> > +
> > +    memory_region_notify_iommu(mr, 0, entry);
> > +}
> > +
> >  static void virtio_iommu_detach_endpoint_from_domain(VirtIOIOMMUEndpoint 
> > *ep)
> >  {
> >      if (!ep->domain) {
> > @@ -307,9 +339,12 @@ static int virtio_iommu_map(VirtIOIOMMU *s,
> >      uint64_t virt_start = le64_to_cpu(req->virt_start);
> >      uint64_t virt_end = le64_to_cpu(req->virt_end);
> >      uint32_t flags = le32_to_cpu(req->flags);
> > +    hwaddr size = virt_end - virt_start + 1;
> > +    VirtioIOMMUNotifierNode *node;
> >      VirtIOIOMMUDomain *domain;
> >      VirtIOIOMMUInterval *interval;
> >      VirtIOIOMMUMapping *mapping;
> > +    VirtIOIOMMUEndpoint *ep;
> >
> >      if (flags & ~VIRTIO_IOMMU_MAP_F_MASK) {
> >          return VIRTIO_IOMMU_S_INVAL;
> > @@ -339,9 +374,37 @@ static int virtio_iommu_map(VirtIOIOMMU *s,
> >
> >      g_tree_insert(domain->mappings, interval, mapping);
> >
> > +    /* All devices in an address-space share mapping */
> > +    QLIST_FOREACH(node, &s->notifiers_list, next) {
> > +        QLIST_FOREACH(ep, &domain->endpoint_list, next) {
> > +            if (ep->id == node->iommu_dev->devfn) {
> > +                virtio_iommu_notify_map(&node->iommu_dev->iommu_mr,
> > +                                        virt_start, phys_start, size);
> > +            }
> > +        }
> > +    }
> > +
> >      return VIRTIO_IOMMU_S_OK;
> >  }
> >
> > +static void virtio_iommu_remove_mapping(VirtIOIOMMU *s, VirtIOIOMMUDomain 
> > *domain,
> > +                                        VirtIOIOMMUInterval *interval)
> > +{
> > +    VirtioIOMMUNotifierNode *node;
> > +    VirtIOIOMMUEndpoint *ep;
> > +
> > +    QLIST_FOREACH(node, &s->notifiers_list, next) {
> > +        QLIST_FOREACH(ep, &domain->endpoint_list, next) {
> > +            if (ep->id == node->iommu_dev->devfn) {
> > +                virtio_iommu_notify_unmap(&node->iommu_dev->iommu_mr,
> > +                                          interval->low,
> > +                                          interval->high - interval->low + 
> > 1);
> > +            }
> > +        }
> > +    }
> > +    g_tree_remove(domain->mappings, (gpointer)(interval));
> > +}
> What about virtio_iommu_put_domain() where you destroy the mapping
> gtree. I guess you also need to send invalidations there?

In virtio_iommu_put_domain(), before destroying domain->mappings we
are calling virtio_iommu_detach_endpoint_from_domain(), which send
invalidations, no ?

> > +
> >  static int virtio_iommu_unmap(VirtIOIOMMU *s,
> >                                struct virtio_iommu_req_unmap *req)
> >  {
> > @@ -368,7 +431,7 @@ static int virtio_iommu_unmap(VirtIOIOMMU *s,
> >          uint64_t current_high = iter_key->high;
> >
> >          if (interval.low <= current_low && interval.high >= current_high) {
> > -            g_tree_remove(domain->mappings, iter_key);
> > +            virtio_iommu_remove_mapping(s, domain, iter_key);
> >              trace_virtio_iommu_unmap_done(domain_id, current_low, 
> > current_high);
> >          } else {
> >              ret = VIRTIO_IOMMU_S_RANGE;
> > @@ -655,6 +718,7 @@ static void virtio_iommu_device_realize(DeviceState 
> > *dev, Error **errp)
> >      VirtIODevice *vdev = VIRTIO_DEVICE(dev);
> >      VirtIOIOMMU *s = VIRTIO_IOMMU(dev);
> >
> > +    QLIST_INIT(&s->notifiers_list);
> >      virtio_init(vdev, "virtio-iommu", VIRTIO_ID_IOMMU,
> >                  sizeof(struct virtio_iommu_config));
> >
> > diff --git a/include/hw/virtio/virtio-iommu.h 
> > b/include/hw/virtio/virtio-iommu.h
> > index 6f67f1020a..4539c8ae72 100644
> > --- a/include/hw/virtio/virtio-iommu.h
> > +++ b/include/hw/virtio/virtio-iommu.h
> > @@ -44,6 +44,11 @@ typedef struct IOMMUPciBus {
> >      IOMMUDevice  *pbdev[0]; /* Parent array is sparse, so dynamically 
> > alloc */
> >  } IOMMUPciBus;
> >
> > +typedef struct VirtioIOMMUNotifierNode {
> > +    IOMMUDevice *iommu_dev;
> > +    QLIST_ENTRY(VirtioIOMMUNotifierNode) next;
> > +} VirtioIOMMUNotifierNode;
> You may use scripts/git.orderfile for a better diff ordering.

ok, run "git config diff.orderFile scripts/git.orderfile"

> > +
> >  typedef struct VirtIOIOMMU {
> >      VirtIODevice parent_obj;
> >      VirtQueue *req_vq;
> > @@ -56,6 +61,7 @@ typedef struct VirtIOIOMMU {
> >      GTree *domains;
> >      QemuMutex mutex;
> >      GTree *endpoints;
> > +    QLIST_HEAD(, VirtioIOMMUNotifierNode) notifiers_list;
> See what was done in smmuv3 and intel. We now directly use a list of
> IOMMUDevice directly. VirtioIOMMUNotifierNode does not bring anything extra.

ok,

Thanks
-Bharat

> >  } VirtIOIOMMU;
> >
> >  #endif
> >
>
> Thanks
>
> Eric
>