[PATCH v11 0/2] vhost-vdpa: add support for vIOMMU

[PATCH v11 0/2] vhost-vdpa: add support for vIOMMU

[Cindy Lu]

These patches are to support vIOMMU in vdpa device

changes in V3
1. Move function vfio_get_xlat_addr to memory.c
2. Use the existing memory listener, while the MR is
iommu MR then call the function iommu_region_add/
iommu_region_del

changes in V4
1.make the comments in vfio_get_xlat_addr more general

changes in V5
1. Address the comments in the last version
2. Add a new arg in the function vfio_get_xlat_addr, which shows whether
the memory is backed by a discard manager. So the device can have its
own warning.

changes in V6
move the error_report for the unpopulated discard back to
memeory_get_xlat_addr

changes in V7
organize the error massage to avoid the duplicate information

changes in V8
Organize the code follow the comments in the last version

changes in V9
Organize the code follow the comments

changes in V10
Address the comments

changes in V11
Address the comments
Fix the crash found in test

Cindy Lu (2):
  vhost-vdpa: Skip the range check while MR is IOMMU
  vhost-vdpa: add support for vIOMMU

 hw/virtio/vhost-vdpa.c         | 168 ++++++++++++++++++++++++++++++---
 include/hw/virtio/vhost-vdpa.h |  10 ++
 2 files changed, 167 insertions(+), 11 deletions(-)

-- 
2.34.3

[PATCH v11 1/2] vhost-vdpa: Skip the range check while MR is IOMMU

[Cindy Lu]

Skip the check in vhost_vdpa_listener_skipped_section() while
MR is IOMMU, Move this check to  vhost_vdpa_iommu_map_notify()

Signed-off-by: Cindy Lu <lulu@redhat.com>
---
 hw/virtio/vhost-vdpa.c | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
index 3ff9ce3501..f0e9963d19 100644
--- a/hw/virtio/vhost-vdpa.c
+++ b/hw/virtio/vhost-vdpa.c
@@ -60,15 +60,22 @@ static bool vhost_vdpa_listener_skipped_section(MemoryRegionSection *section,
                      iova_min, section->offset_within_address_space);
         return true;
     }
+    /*
+     * While using vIOMMU, Sometimes the section will be larger than iova_max
+     * but the memory that  actually mapping is smaller, So skip the check
+     * here. Will add the check in vhost_vdpa_iommu_map_notify,
+     *There is the real size that maps to the kernel
+     */
 
-    llend = vhost_vdpa_section_end(section);
-    if (int128_gt(llend, int128_make64(iova_max))) {
-        error_report("RAM section out of device range (max=0x%" PRIx64
-                     ", end addr=0x%" PRIx64 ")",
-                     iova_max, int128_get64(llend));
-        return true;
+    if (!memory_region_is_iommu(section->mr)) {
+        llend = vhost_vdpa_section_end(section);
+        if (int128_gt(llend, int128_make64(iova_max))) {
+            error_report("RAM section out of device range (max=0x%" PRIx64
+                         ", end addr=0x%" PRIx64 ")",
+                         iova_max, int128_get64(llend));
+            return true;
+        }
     }
-
     return false;
 }
 
-- 
2.34.3

[PATCH v11 2/2] vhost-vdpa: add support for vIOMMU

[Cindy Lu]

Add support for vIOMMU. add the new function to deal with iommu MR.
- during iommu_region_add register a specific IOMMU notifier,
 and store all notifiers in a list.
- during iommu_region_del, compare and delete the IOMMU notifier from the list

Verified in vp_vdpa and vdpa_sim_net driver

Signed-off-by: Cindy Lu <lulu@redhat.com>
---
 hw/virtio/vhost-vdpa.c         | 147 ++++++++++++++++++++++++++++++++-
 include/hw/virtio/vhost-vdpa.h |  10 +++
 2 files changed, 153 insertions(+), 4 deletions(-)

diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
index f0e9963d19..4137094fef 100644
--- a/hw/virtio/vhost-vdpa.c
+++ b/hw/virtio/vhost-vdpa.c
@@ -26,6 +26,7 @@
 #include "cpu.h"
 #include "trace.h"
 #include "qapi/error.h"
+#include "hw/virtio/virtio-access.h"
 
 /*
  * Return one past the end of the end of section. Be careful with uint64_t
@@ -180,6 +181,119 @@ static void vhost_vdpa_listener_commit(MemoryListener *listener)
     v->iotlb_batch_begin_sent = false;
 }
 
+static void vhost_vdpa_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
+{
+    struct vdpa_iommu *iommu = container_of(n, struct vdpa_iommu, n);
+
+    hwaddr iova = iotlb->iova + iommu->iommu_offset;
+    struct vhost_vdpa *v = iommu->dev;
+    void *vaddr;
+    int ret;
+    Int128 llend;
+
+    if (iotlb->target_as != &address_space_memory) {
+        error_report("Wrong target AS \"%s\", only system memory is allowed",
+                     iotlb->target_as->name ? iotlb->target_as->name : "none");
+        return;
+    }
+    RCU_READ_LOCK_GUARD();
+    /* check if RAM section out of device range */
+    llend =
+        int128_add(int128_makes64(iotlb->addr_mask + 1), int128_makes64(iova));
+    if (int128_gt(llend, int128_make64(v->iova_range.last))) {
+        error_report("RAM section out of device range (max=0x%" PRIx64
+                     ", end addr=0x%" PRIx64 ")",
+                     v->iova_range.last, int128_get64(llend));
+        return;
+    }
+
+    vhost_vdpa_iotlb_batch_begin_once(v);
+
+    if ((iotlb->perm & IOMMU_RW) != IOMMU_NONE) {
+        bool read_only;
+
+        if (!memory_get_xlat_addr(iotlb, &vaddr, NULL, &read_only, NULL)) {
+            return;
+        }
+
+
+        ret =
+            vhost_vdpa_dma_map(v, iova, iotlb->addr_mask + 1, vaddr, read_only);
+        if (ret) {
+            error_report("vhost_vdpa_dma_map(%p, 0x%" HWADDR_PRIx ", "
+                         "0x%" HWADDR_PRIx ", %p) = %d (%m)",
+                         v, iova, iotlb->addr_mask + 1, vaddr, ret);
+        }
+    } else {
+        ret = vhost_vdpa_dma_unmap(v, iova, iotlb->addr_mask + 1);
+        if (ret) {
+            error_report("vhost_vdpa_dma_unmap(%p, 0x%" HWADDR_PRIx ", "
+                         "0x%" HWADDR_PRIx ") = %d (%m)",
+                         v, iova, iotlb->addr_mask + 1, ret);
+        }
+    }
+}
+
+static void vhost_vdpa_iommu_region_add(MemoryListener *listener,
+                                        MemoryRegionSection *section)
+{
+    struct vhost_vdpa *v = container_of(listener, struct vhost_vdpa, listener);
+
+    struct vdpa_iommu *iommu;
+    Int128 end;
+    int iommu_idx;
+    IOMMUMemoryRegion *iommu_mr;
+    int ret;
+
+    iommu_mr = IOMMU_MEMORY_REGION(section->mr);
+
+    iommu = g_malloc0(sizeof(*iommu));
+    end = int128_add(int128_make64(section->offset_within_region),
+            section->size);
+    end = int128_sub(end, int128_one());
+    iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr,
+            MEMTXATTRS_UNSPECIFIED);
+
+    iommu->iommu_mr = iommu_mr;
+
+    iommu_notifier_init(
+        &iommu->n, vhost_vdpa_iommu_map_notify, IOMMU_NOTIFIER_IOTLB_EVENTS,
+        section->offset_within_region, int128_get64(end), iommu_idx);
+    iommu->iommu_offset =
+        section->offset_within_address_space - section->offset_within_region;
+    iommu->dev = v;
+
+    ret = memory_region_register_iommu_notifier(section->mr, &iommu->n, NULL);
+    if (ret) {
+        g_free(iommu);
+        return;
+    }
+
+    QLIST_INSERT_HEAD(&v->iommu_list, iommu, iommu_next);
+    memory_region_iommu_replay(iommu->iommu_mr, &iommu->n);
+
+    return;
+}
+
+static void vhost_vdpa_iommu_region_del(MemoryListener *listener,
+                                        MemoryRegionSection *section)
+{
+    struct vhost_vdpa *v = container_of(listener, struct vhost_vdpa, listener);
+
+    struct vdpa_iommu *iommu;
+
+    QLIST_FOREACH(iommu, &v->iommu_list, iommu_next)
+    {
+        if (MEMORY_REGION(iommu->iommu_mr) == section->mr &&
+            iommu->n.start == section->offset_within_region) {
+            memory_region_unregister_iommu_notifier(section->mr, &iommu->n);
+            QLIST_REMOVE(iommu, iommu_next);
+            g_free(iommu);
+            break;
+        }
+    }
+}
+
 static void vhost_vdpa_listener_region_add(MemoryListener *listener,
                                            MemoryRegionSection *section)
 {
@@ -193,6 +307,10 @@ static void vhost_vdpa_listener_region_add(MemoryListener *listener,
                                             v->iova_range.last)) {
         return;
     }
+    if (memory_region_is_iommu(section->mr)) {
+        vhost_vdpa_iommu_region_add(listener, section);
+        return;
+    }
 
     if (unlikely((section->offset_within_address_space & ~TARGET_PAGE_MASK) !=
                  (section->offset_within_region & ~TARGET_PAGE_MASK))) {
@@ -267,6 +385,9 @@ static void vhost_vdpa_listener_region_del(MemoryListener *listener,
                                             v->iova_range.last)) {
         return;
     }
+    if (memory_region_is_iommu(section->mr)) {
+        vhost_vdpa_iommu_region_del(listener, section);
+    }
 
     if (unlikely((section->offset_within_address_space & ~TARGET_PAGE_MASK) !=
                  (section->offset_within_region & ~TARGET_PAGE_MASK))) {
@@ -277,7 +398,8 @@ static void vhost_vdpa_listener_region_del(MemoryListener *listener,
     iova = TARGET_PAGE_ALIGN(section->offset_within_address_space);
     llend = vhost_vdpa_section_end(section);
 
-    trace_vhost_vdpa_listener_region_del(v, iova, int128_get64(llend));
+    trace_vhost_vdpa_listener_region_del(
+        v, iova, int128_get64(int128_sub(llend, int128_one())));
 
     if (int128_ge(int128_make64(iova), llend)) {
         return;
@@ -300,9 +422,26 @@ static void vhost_vdpa_listener_region_del(MemoryListener *listener,
         vhost_iova_tree_remove(v->iova_tree, result);
     }
     vhost_vdpa_iotlb_batch_begin_once(v);
+
+    /*
+     * The unmap ioctl doesn't accept a full 64-bit. need to check it
+     */
+    if (int128_eq(llsize, int128_2_64())) {
+        llsize = int128_rshift(llsize, 1);
+        ret = vhost_vdpa_dma_unmap(v, iova, int128_get64(llsize));
+        if (ret) {
+            error_report("vhost_vdpa_dma_unmap(%p, 0x%" HWADDR_PRIx ", "
+                         "0x%" HWADDR_PRIx ") = %d (%m)",
+                         v, iova, int128_get64(llsize), ret);
+        }
+        iova += int128_get64(llsize);
+    }
+
     ret = vhost_vdpa_dma_unmap(v, iova, int128_get64(llsize));
     if (ret) {
-        error_report("vhost_vdpa dma unmap error!");
+        error_report("vhost_vdpa_dma_unmap(%p, 0x%" HWADDR_PRIx ", "
+                     "0x%" HWADDR_PRIx ") = %d (%m)",
+                     v, iova, int128_get64(llsize), ret);
     }
 
     memory_region_unref(section->mr);
@@ -594,7 +733,6 @@ static int vhost_vdpa_cleanup(struct vhost_dev *dev)
     v = dev->opaque;
     trace_vhost_vdpa_cleanup(dev, v);
     vhost_vdpa_host_notifiers_uninit(dev, dev->nvqs);
-    memory_listener_unregister(&v->listener);
     vhost_vdpa_svq_cleanup(dev);
 
     dev->opaque = NULL;
@@ -1134,7 +1272,8 @@ static int vhost_vdpa_dev_start(struct vhost_dev *dev, bool started)
     }
 
     if (started) {
-        memory_listener_register(&v->listener, &address_space_memory);
+        memory_listener_register(&v->listener, dev->vdev->dma_as);
+
         return vhost_vdpa_add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);
     } else {
         vhost_vdpa_reset_device(dev);
diff --git a/include/hw/virtio/vhost-vdpa.h b/include/hw/virtio/vhost-vdpa.h
index d10a89303e..564acda810 100644
--- a/include/hw/virtio/vhost-vdpa.h
+++ b/include/hw/virtio/vhost-vdpa.h
@@ -41,8 +41,18 @@ typedef struct vhost_vdpa {
     void *shadow_vq_ops_opaque;
     struct vhost_dev *dev;
     VhostVDPAHostNotifier notifier[VIRTIO_QUEUE_MAX];
+    QLIST_HEAD(, vdpa_iommu) iommu_list;
+    IOMMUNotifier n;
 } VhostVDPA;
 
+typedef struct vdpa_iommu {
+    struct vhost_vdpa *dev;
+    IOMMUMemoryRegion *iommu_mr;
+    hwaddr iommu_offset;
+    IOMMUNotifier n;
+    QLIST_ENTRY(vdpa_iommu) iommu_next;
+} VDPAIOMMUState;
+
 int vhost_vdpa_dma_map(struct vhost_vdpa *v, hwaddr iova, hwaddr size,
                        void *vaddr, bool readonly);
 int vhost_vdpa_dma_unmap(struct vhost_vdpa *v, hwaddr iova, hwaddr size);
-- 
2.34.3

Re: [PATCH v11 1/2] vhost-vdpa: Skip the range check while MR is IOMMU

[Jason Wang]

On Wed, Nov 30, 2022 at 1:33 PM Cindy Lu <lulu@redhat.com> wrote:
>
> Skip the check in vhost_vdpa_listener_skipped_section() while
> MR is IOMMU, Move this check to  vhost_vdpa_iommu_map_notify()
>
> Signed-off-by: Cindy Lu <lulu@redhat.com>
> ---
>  hw/virtio/vhost-vdpa.c | 21 ++++++++++++++-------
>  1 file changed, 14 insertions(+), 7 deletions(-)
>
> diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
> index 3ff9ce3501..f0e9963d19 100644
> --- a/hw/virtio/vhost-vdpa.c
> +++ b/hw/virtio/vhost-vdpa.c
> @@ -60,15 +60,22 @@ static bool vhost_vdpa_listener_skipped_section(MemoryRegionSection *section,
>                       iova_min, section->offset_within_address_space);
>          return true;
>      }
> +    /*
> +     * While using vIOMMU, Sometimes the section will be larger than iova_max
> +     * but the memory that  actually mapping is smaller, So skip the check
> +     * here. Will add the check in vhost_vdpa_iommu_map_notify,
> +     *There is the real size that maps to the kernel
> +     */
>

I suggest squashing this into the next patch since we haven't
implemented vhost_vdpa_iommu_map_notify() yet.

Thanks

> -    llend = vhost_vdpa_section_end(section);
> -    if (int128_gt(llend, int128_make64(iova_max))) {
> -        error_report("RAM section out of device range (max=0x%" PRIx64
> -                     ", end addr=0x%" PRIx64 ")",
> -                     iova_max, int128_get64(llend));
> -        return true;
> +    if (!memory_region_is_iommu(section->mr)) {
> +        llend = vhost_vdpa_section_end(section);
> +        if (int128_gt(llend, int128_make64(iova_max))) {
> +            error_report("RAM section out of device range (max=0x%" PRIx64
> +                         ", end addr=0x%" PRIx64 ")",
> +                         iova_max, int128_get64(llend));
> +            return true;
> +        }
>      }
> -
>      return false;
>  }
>
> --
> 2.34.3
>

Re: [PATCH v11 1/2] vhost-vdpa: Skip the range check while MR is IOMMU

[Cindy Lu]

On Thu, 8 Dec 2022 at 15:42, Jason Wang <jasowang@redhat.com> wrote:
>
> On Wed, Nov 30, 2022 at 1:33 PM Cindy Lu <lulu@redhat.com> wrote:
> >
> > Skip the check in vhost_vdpa_listener_skipped_section() while
> > MR is IOMMU, Move this check to  vhost_vdpa_iommu_map_notify()
> >
> > Signed-off-by: Cindy Lu <lulu@redhat.com>
> > ---
> >  hw/virtio/vhost-vdpa.c | 21 ++++++++++++++-------
> >  1 file changed, 14 insertions(+), 7 deletions(-)
> >
> > diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
> > index 3ff9ce3501..f0e9963d19 100644
> > --- a/hw/virtio/vhost-vdpa.c
> > +++ b/hw/virtio/vhost-vdpa.c
> > @@ -60,15 +60,22 @@ static bool vhost_vdpa_listener_skipped_section(MemoryRegionSection *section,
> >                       iova_min, section->offset_within_address_space);
> >          return true;
> >      }
> > +    /*
> > +     * While using vIOMMU, Sometimes the section will be larger than iova_max
> > +     * but the memory that  actually mapping is smaller, So skip the check
> > +     * here. Will add the check in vhost_vdpa_iommu_map_notify,
> > +     *There is the real size that maps to the kernel
> > +     */
> >
>
> I suggest squashing this into the next patch since we haven't
> implemented vhost_vdpa_iommu_map_notify() yet.
>
> Thanks
>
Sure, will do
Thanks
Cindy
> > -    llend = vhost_vdpa_section_end(section);
> > -    if (int128_gt(llend, int128_make64(iova_max))) {
> > -        error_report("RAM section out of device range (max=0x%" PRIx64
> > -                     ", end addr=0x%" PRIx64 ")",
> > -                     iova_max, int128_get64(llend));
> > -        return true;
> > +    if (!memory_region_is_iommu(section->mr)) {
> > +        llend = vhost_vdpa_section_end(section);
> > +        if (int128_gt(llend, int128_make64(iova_max))) {
> > +            error_report("RAM section out of device range (max=0x%" PRIx64
> > +                         ", end addr=0x%" PRIx64 ")",
> > +                         iova_max, int128_get64(llend));
> > +            return true;
> > +        }
> >      }
> > -
> >      return false;
> >  }
> >
> > --
> > 2.34.3
> >
>