[PATCH for-5.0 v11 07/20] virtio-iommu: Implement map/unmap

[Eric Auger <eric.auger@redhat.com>]

This patch implements virtio_iommu_map/unmap.

Signed-off-by: Eric Auger <eric.auger@redhat.com>

---

v10 -> v11:
- revisit the implementation of unmap according to Peter's suggestion
- removed virt_addr and size from viommu_mapping struct
- use g_tree_lookup_extended()
- return VIRTIO_IOMMU_S_RANGE in case a mapping were
  to be split on unmap (instead of INVAL)

v5 -> v6:
- use new v0.6 fields
- replace error_report by qemu_log_mask

v3 -> v4:
- implement unmap semantics as specified in v0.4
---
 hw/virtio/trace-events   |  1 +
 hw/virtio/virtio-iommu.c | 65 ++++++++++++++++++++++++++++++++++++++--
 2 files changed, 64 insertions(+), 2 deletions(-)

diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
index a373bdebb3..f25359cee2 100644
--- a/hw/virtio/trace-events
+++ b/hw/virtio/trace-events
@@ -65,6 +65,7 @@ virtio_iommu_attach(uint32_t domain_id, uint32_t ep_id) "domain=%d endpoint=%d"
 virtio_iommu_detach(uint32_t domain_id, uint32_t ep_id) "domain=%d endpoint=%d"
 virtio_iommu_map(uint32_t domain_id, uint64_t virt_start, uint64_t virt_end, uint64_t phys_start, uint32_t flags) "domain=%d virt_start=0x%"PRIx64" virt_end=0x%"PRIx64 " phys_start=0x%"PRIx64" flags=%d"
 virtio_iommu_unmap(uint32_t domain_id, uint64_t virt_start, uint64_t virt_end) "domain=%d virt_start=0x%"PRIx64" virt_end=0x%"PRIx64
+virtio_iommu_unmap_done(uint32_t domain_id, uint64_t virt_start, uint64_t virt_end) "domain=%d virt_start=0x%"PRIx64" virt_end=0x%"PRIx64
 virtio_iommu_translate(const char *name, uint32_t rid, uint64_t iova, int flag) "mr=%s rid=%d addr=0x%"PRIx64" flag=%d"
 virtio_iommu_init_iommu_mr(char *iommu_mr) "init %s"
 virtio_iommu_get_endpoint(uint32_t ep_id) "Alloc endpoint=%d"
diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
index 138d5b2a9c..f0a56833a2 100644
--- a/hw/virtio/virtio-iommu.c
+++ b/hw/virtio/virtio-iommu.c
@@ -18,6 +18,7 @@
  */
 
 #include "qemu/osdep.h"
+#include "qemu/log.h"
 #include "qemu/iov.h"
 #include "qemu-common.h"
 #include "hw/qdev-properties.h"
@@ -55,6 +56,11 @@ typedef struct viommu_interval {
     uint64_t high;
 } viommu_interval;
 
+typedef struct viommu_mapping {
+    uint64_t phys_addr;
+    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);
@@ -238,10 +244,35 @@ 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);
+    viommu_domain *domain;
+    viommu_interval *interval;
+    viommu_mapping *mapping;
+
+    interval = g_malloc0(sizeof(*interval));
+
+    interval->low = virt_start;
+    interval->high = virt_end;
+
+    domain = g_tree_lookup(s->domains, GUINT_TO_POINTER(domain_id));
+    if (!domain) {
+        return VIRTIO_IOMMU_S_NOENT;
+    }
+
+    mapping = g_tree_lookup(domain->mappings, (gpointer)interval);
+    if (mapping) {
+        g_free(interval);
+        return VIRTIO_IOMMU_S_INVAL;
+    }
 
     trace_virtio_iommu_map(domain_id, virt_start, virt_end, phys_start, flags);
 
-    return VIRTIO_IOMMU_S_UNSUPP;
+    mapping = g_malloc0(sizeof(*mapping));
+    mapping->phys_addr = phys_start;
+    mapping->flags = flags;
+
+    g_tree_insert(domain->mappings, interval, mapping);
+
+    return VIRTIO_IOMMU_S_OK;
 }
 
 static int virtio_iommu_unmap(VirtIOIOMMU *s,
@@ -250,10 +281,40 @@ static int virtio_iommu_unmap(VirtIOIOMMU *s,
     uint32_t domain_id = le32_to_cpu(req->domain);
     uint64_t virt_start = le64_to_cpu(req->virt_start);
     uint64_t virt_end = le64_to_cpu(req->virt_end);
+    viommu_mapping *iter_val;
+    viommu_interval interval, *iter_key;
+    viommu_domain *domain;
+    int ret = VIRTIO_IOMMU_S_OK;
 
     trace_virtio_iommu_unmap(domain_id, virt_start, virt_end);
 
-    return VIRTIO_IOMMU_S_UNSUPP;
+    domain = g_tree_lookup(s->domains, GUINT_TO_POINTER(domain_id));
+    if (!domain) {
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: no domain\n", __func__);
+        return VIRTIO_IOMMU_S_NOENT;
+    }
+    interval.low = virt_start;
+    interval.high = virt_end;
+
+    while (g_tree_lookup_extended(domain->mappings, &interval,
+                                  (void **)&iter_key, (void**)&iter_val)) {
+        uint64_t current_low = iter_key->low;
+        uint64_t current_high = iter_key->high;
+
+        if (interval.low <= current_low && interval.high >= current_high) {
+            g_tree_remove(domain->mappings, iter_key);
+            trace_virtio_iommu_unmap_done(domain_id, current_low, current_high);
+        } else {
+            qemu_log_mask(LOG_GUEST_ERROR,
+                "%s: domain= %d Unmap [0x%"PRIx64",0x%"PRIx64"] forbidden as "
+                "it would split existing mapping [0x%"PRIx64", 0x%"PRIx64"]\n",
+                __func__, domain_id, interval.low, interval.high,
+                current_low, current_high);
+            ret = VIRTIO_IOMMU_S_RANGE;
+            break;
+        }
+    }
+    return ret;
 }
 
 static int virtio_iommu_iov_to_req(struct iovec *iov,
-- 
2.20.1