[PATCH v12 05/13] virtio-iommu: Endpoint and domains structs and helpers

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

This patch introduce domain and endpoint internal
datatypes. Both are stored in RB trees. The domain
owns a list of endpoints attached to it.

Helpers to get/put end points and domains are introduced.
get() helpers will become static in subsequent patches.

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

---

v11 -> v12:
- s/uint/guint (docker-mingw@fedora build test failure)
- s/viommu_/VirtIOIOMMU + CamelCase
- Before creating an endpoint, check the sid is one from a
  device protected by the iommu, otherwise returns NULL
- add assert of endpoint put to check the endpoint was detached
  from any domain
- destroy and re-allocate the trees on reset

v10 -> v11:
- fixed interval_cmp (<= -> < and >= -> >)
- removed unused viommu field from endpoint
- removed Bharat's R-b

v9 -> v10:
- added Bharat's R-b

v6 -> v7:
- on virtio_iommu_find_add_as the bus number computation may
  not be finalized yet so we cannot register the EPs at that time.
  Hence, let's remove the get_endpoint and also do not use the
  bus number for building the memory region name string (only
  used for debug though).

v4 -> v5:
- initialize as->endpoint_list

v3 -> v4:
- new separate patch
---
 hw/virtio/trace-events   |   4 ++
 hw/virtio/virtio-iommu.c | 128 ++++++++++++++++++++++++++++++++++++++-
 2 files changed, 130 insertions(+), 2 deletions(-)

diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
index 10a2b120f3..15595f8cd7 100644
--- a/hw/virtio/trace-events
+++ b/hw/virtio/trace-events
@@ -66,3 +66,7 @@ virtio_iommu_map(uint32_t domain_id, uint64_t virt_start, uint64_t virt_end, uin
 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_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"
+virtio_iommu_put_endpoint(uint32_t ep_id) "Free endpoint=%d"
+virtio_iommu_get_domain(uint32_t domain_id) "Alloc domain=%d"
+virtio_iommu_put_domain(uint32_t domain_id) "Free domain=%d"
diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
index acc939f334..6a03c3d7ae 100644
--- a/hw/virtio/virtio-iommu.c
+++ b/hw/virtio/virtio-iommu.c
@@ -32,10 +32,29 @@
 #include "hw/virtio/virtio-bus.h"
 #include "hw/virtio/virtio-access.h"
 #include "hw/virtio/virtio-iommu.h"
+#include "hw/pci/pci_bus.h"
+#include "hw/pci/pci.h"
 
 /* Max size */
 #define VIOMMU_DEFAULT_QUEUE_SIZE 256
 
+typedef struct VirtIOIOMMUDomain {
+    uint32_t id;
+    GTree *mappings;
+    QLIST_HEAD(, VirtIOIOMMUEndpoint) endpoint_list;
+} VirtIOIOMMUDomain;
+
+typedef struct VirtIOIOMMUEndpoint {
+    uint32_t id;
+    VirtIOIOMMUDomain *domain;
+    QLIST_ENTRY(VirtIOIOMMUEndpoint) next;
+} VirtIOIOMMUEndpoint;
+
+typedef struct VirtIOIOMMUInterval {
+    uint64_t low;
+    uint64_t high;
+} VirtIOIOMMUInterval;
+
 static inline uint16_t virtio_iommu_get_sid(IOMMUDevice *dev)
 {
     return PCI_BUILD_BDF(pci_bus_num(dev->bus), dev->devfn);
@@ -65,8 +84,7 @@ static IOMMUPciBus *iommu_find_iommu_pcibus(VirtIOIOMMU *s, uint8_t bus_num)
     return iommu_pci_bus;
 }
 
-IOMMUMemoryRegion *virtio_iommu_mr(VirtIOIOMMU *s, uint32_t sid);
-IOMMUMemoryRegion *virtio_iommu_mr(VirtIOIOMMU *s, uint32_t sid)
+static IOMMUMemoryRegion *virtio_iommu_mr(VirtIOIOMMU *s, uint32_t sid)
 {
     uint8_t bus_n, devfn;
     IOMMUPciBus *iommu_pci_bus;
@@ -84,6 +102,88 @@ IOMMUMemoryRegion *virtio_iommu_mr(VirtIOIOMMU *s, uint32_t sid)
     return NULL;
 }
 
+static gint interval_cmp(gconstpointer a, gconstpointer b, gpointer user_data)
+{
+    VirtIOIOMMUInterval *inta = (VirtIOIOMMUInterval *)a;
+    VirtIOIOMMUInterval *intb = (VirtIOIOMMUInterval *)b;
+
+    if (inta->high < intb->low) {
+        return -1;
+    } else if (intb->high < inta->low) {
+        return 1;
+    } else {
+        return 0;
+    }
+}
+
+static void virtio_iommu_detach_endpoint_from_domain(VirtIOIOMMUEndpoint *ep)
+{
+    QLIST_REMOVE(ep, next);
+    ep->domain = NULL;
+}
+
+VirtIOIOMMUEndpoint *virtio_iommu_get_endpoint(VirtIOIOMMU *s, uint32_t ep_id);
+VirtIOIOMMUEndpoint *virtio_iommu_get_endpoint(VirtIOIOMMU *s, uint32_t ep_id)
+{
+    VirtIOIOMMUEndpoint *ep;
+
+    ep = g_tree_lookup(s->endpoints, GUINT_TO_POINTER(ep_id));
+    if (ep) {
+        return ep;
+    }
+    if (!virtio_iommu_mr(s, ep_id)) {
+        return NULL;
+    }
+    ep = g_malloc0(sizeof(*ep));
+    ep->id = ep_id;
+    trace_virtio_iommu_get_endpoint(ep_id);
+    g_tree_insert(s->endpoints, GUINT_TO_POINTER(ep_id), ep);
+    return ep;
+}
+
+static void virtio_iommu_put_endpoint(gpointer data)
+{
+    VirtIOIOMMUEndpoint *ep = (VirtIOIOMMUEndpoint *)data;
+
+    assert(!ep->domain);
+
+    trace_virtio_iommu_put_endpoint(ep->id);
+    g_free(ep);
+}
+
+VirtIOIOMMUDomain *virtio_iommu_get_domain(VirtIOIOMMU *s, uint32_t domain_id);
+VirtIOIOMMUDomain *virtio_iommu_get_domain(VirtIOIOMMU *s, uint32_t domain_id)
+{
+    VirtIOIOMMUDomain *domain;
+
+    domain = g_tree_lookup(s->domains, GUINT_TO_POINTER(domain_id));
+    if (domain) {
+        return domain;
+    }
+    domain = g_malloc0(sizeof(*domain));
+    domain->id = domain_id;
+    domain->mappings = g_tree_new_full((GCompareDataFunc)interval_cmp,
+                                   NULL, (GDestroyNotify)g_free,
+                                   (GDestroyNotify)g_free);
+    g_tree_insert(s->domains, GUINT_TO_POINTER(domain_id), domain);
+    QLIST_INIT(&domain->endpoint_list);
+    trace_virtio_iommu_get_domain(domain_id);
+    return domain;
+}
+
+static void virtio_iommu_put_domain(gpointer data)
+{
+    VirtIOIOMMUDomain *domain = (VirtIOIOMMUDomain *)data;
+    VirtIOIOMMUEndpoint *iter, *tmp;
+
+    QLIST_FOREACH_SAFE(iter, &domain->endpoint_list, next, tmp) {
+        virtio_iommu_detach_endpoint_from_domain(iter);
+    }
+    g_tree_destroy(domain->mappings);
+    trace_virtio_iommu_put_domain(domain->id);
+    g_free(domain);
+}
+
 static AddressSpace *virtio_iommu_find_add_as(PCIBus *bus, void *opaque,
                                               int devfn)
 {
@@ -328,6 +428,13 @@ static const VMStateDescription vmstate_virtio_iommu_device = {
     .unmigratable = 1,
 };
 
+static gint int_cmp(gconstpointer a, gconstpointer b, gpointer user_data)
+{
+    guint ua = GPOINTER_TO_UINT(a);
+    guint ub = GPOINTER_TO_UINT(b);
+    return (ua > ub) - (ua < ub);
+}
+
 static void virtio_iommu_device_realize(DeviceState *dev, Error **errp)
 {
     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
@@ -369,13 +476,30 @@ static void virtio_iommu_device_realize(DeviceState *dev, Error **errp)
 static void virtio_iommu_device_unrealize(DeviceState *dev, Error **errp)
 {
     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+    VirtIOIOMMU *s = VIRTIO_IOMMU(dev);
+
+    g_tree_destroy(s->domains);
+    g_tree_destroy(s->endpoints);
 
     virtio_cleanup(vdev);
 }
 
 static void virtio_iommu_device_reset(VirtIODevice *vdev)
 {
+    VirtIOIOMMU *s = VIRTIO_IOMMU(vdev);
+
     trace_virtio_iommu_device_reset();
+
+    if (s->domains) {
+        g_tree_destroy(s->domains);
+    }
+    if (s->endpoints) {
+        g_tree_destroy(s->endpoints);
+    }
+    s->domains = g_tree_new_full((GCompareDataFunc)int_cmp,
+                                 NULL, NULL, virtio_iommu_put_domain);
+    s->endpoints = g_tree_new_full((GCompareDataFunc)int_cmp,
+                                   NULL, NULL, virtio_iommu_put_endpoint);
 }
 
 static void virtio_iommu_set_status(VirtIODevice *vdev, uint8_t status)
-- 
2.20.1