[Qemu-devel] [RFC v4 08/16] virtio-iommu: Implement map/unmap

[Eric Auger]

This patch implements virtio_iommu_map/unmap.

Signed-off-by: Eric Auger <address@hidden>

---

v3 -> v4:
- implement unmap semantics as specified in v0.4
---
 hw/virtio/trace-events   |  3 ++
 hw/virtio/virtio-iommu.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 92 insertions(+), 2 deletions(-)

diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
index 74b92d3..da298c1 100644
--- a/hw/virtio/trace-events
+++ b/hw/virtio/trace-events
@@ -42,3 +42,6 @@ virtio_iommu_get_dev(uint32_t devid) "Alloc devid=%d"
 virtio_iommu_put_dev(uint32_t devid) "Free devid=%d"
 virtio_iommu_get_as(uint32_t asid) "Alloc asid=%d"
 virtio_iommu_put_as(uint32_t asid) "Free asid=%d"
+virtio_iommu_unmap_left_interval(uint64_t low, uint64_t high, uint64_t 
next_low, uint64_t next_high) "Unmap left [0x%"PRIx64",0x%"PRIx64"], new 
interval=[0x%"PRIx64",0x%"PRIx64"]"
+virtio_iommu_unmap_right_interval(uint64_t low, uint64_t high, uint64_t 
next_low, uint64_t next_high) "Unmap right [0x%"PRIx64",0x%"PRIx64"], new 
interval=[0x%"PRIx64",0x%"PRIx64"]"
+virtio_iommu_unmap_inc_interval(uint64_t low, uint64_t high) "Unmap inc 
[0x%"PRIx64",0x%"PRIx64"]"
diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
index bd859fb..6f1a7d1 100644
--- a/hw/virtio/virtio-iommu.c
+++ b/hw/virtio/virtio-iommu.c
@@ -56,6 +56,13 @@ typedef struct viommu_interval {
     uint64_t high;
 } viommu_interval;
 
+typedef struct viommu_mapping {
+    uint64_t virt_addr;
+    uint64_t phys_addr;
+    uint64_t size;
+    uint32_t flags;
+} viommu_mapping;
+
 static inline uint16_t virtio_iommu_get_sid(IOMMUDevice *dev)
 {
     return PCI_BUILD_BDF(pci_bus_num(dev->bus), dev->devfn);
@@ -264,10 +271,37 @@ static int virtio_iommu_map(VirtIOIOMMU *s,
     uint64_t virt_addr = le64_to_cpu(req->virt_addr);
     uint64_t size = le64_to_cpu(req->size);
     uint32_t flags = le32_to_cpu(req->flags);
+    viommu_as *as;
+    viommu_interval *interval;
+    viommu_mapping *mapping;
+
+    interval = g_malloc0(sizeof(*interval));
+
+    interval->low = virt_addr;
+    interval->high = virt_addr + size - 1;
+
+    as = g_tree_lookup(s->address_spaces, GUINT_TO_POINTER(asid));
+    if (!as) {
+        return VIRTIO_IOMMU_S_NOENT;
+    }
+
+    mapping = g_tree_lookup(as->mappings, (gpointer)interval);
+    if (mapping) {
+        g_free(interval);
+        return VIRTIO_IOMMU_S_INVAL;
+    }
 
     trace_virtio_iommu_map(asid, phys_addr, virt_addr, size, flags);
 
-    return VIRTIO_IOMMU_S_UNSUPP;
+    mapping = g_malloc0(sizeof(*mapping));
+    mapping->virt_addr = virt_addr;
+    mapping->phys_addr = phys_addr;
+    mapping->size = size;
+    mapping->flags = flags;
+
+    g_tree_insert(as->mappings, interval, mapping);
+
+    return VIRTIO_IOMMU_S_OK;
 }
 
 static int virtio_iommu_unmap(VirtIOIOMMU *s,
@@ -276,10 +310,63 @@ static int virtio_iommu_unmap(VirtIOIOMMU *s,
     uint32_t asid = le32_to_cpu(req->address_space);
     uint64_t virt_addr = le64_to_cpu(req->virt_addr);
     uint64_t size = le64_to_cpu(req->size);
+    viommu_mapping *mapping;
+    viommu_interval interval;
+    viommu_as *as;
 
     trace_virtio_iommu_unmap(asid, virt_addr, size);
 
-    return VIRTIO_IOMMU_S_UNSUPP;
+    as = g_tree_lookup(s->address_spaces, GUINT_TO_POINTER(asid));
+    if (!as) {
+        error_report("%s: no as", __func__);
+        return VIRTIO_IOMMU_S_NOENT;
+    }
+    interval.low = virt_addr;
+    interval.high = virt_addr + size - 1;
+
+    mapping = g_tree_lookup(as->mappings, (gpointer)(&interval));
+
+    while (mapping) {
+        viommu_interval current;
+        uint64_t low  = mapping->virt_addr;
+        uint64_t high = mapping->virt_addr + mapping->size - 1;
+
+        current.low = low;
+        current.high = high;
+
+        if (low == interval.low && size >= mapping->size) {
+            g_tree_remove(as->mappings, (gpointer)(&current));
+            interval.low = high + 1;
+            trace_virtio_iommu_unmap_left_interval(current.low, current.high,
+                interval.low, interval.high);
+        } else if (high == interval.high && size >= mapping->size) {
+            trace_virtio_iommu_unmap_right_interval(current.low, current.high,
+                interval.low, interval.high);
+            g_tree_remove(as->mappings, (gpointer)(&current));
+            interval.high = low - 1;
+        } else if (low > interval.low && high < interval.high) {
+            trace_virtio_iommu_unmap_inc_interval(current.low, current.high);
+            g_tree_remove(as->mappings, (gpointer)(&current));
+        } else {
+            break;
+        }
+        if (interval.low >= interval.high) {
+            return VIRTIO_IOMMU_S_OK;
+        } else {
+            mapping = g_tree_lookup(as->mappings, (gpointer)(&interval));
+        }
+    }
+
+    if (mapping) {
+        error_report("****** %s: Unmap 0x%"PRIx64" size=0x%"PRIx64
+                     " from 0x%"PRIx64" size=0x%"PRIx64" is not supported",
+                     __func__, interval.low, size,
+                     mapping->virt_addr, mapping->size);
+    } else {
+        return VIRTIO_IOMMU_S_OK;
+    }
+
+    return VIRTIO_IOMMU_S_INVAL;
 }
 
 #define get_payload_size(req) (\
-- 
2.5.5