[Xen-devel] [PATCH v3 17/24] xen/passthrough: arm: release earlier the DT devices assigned to a guest

[Julien Grall <julien.grall@xxxxxxxxxx>]

The toolstack may not have deassign every device used by a guest.
Therefore we have to go through the device list and removing them before
asking the IOMMU drivers to release memory for this domain.

This can be done by moving the call to the release function when we
relinquish the resources. The IOMMU part will be destroyed later when
the domain is freed.

Signed-off-by: Julien Grall <julien.grall@xxxxxxxxxx>
Cc: Jan Beulich <jbeulich@xxxxxxxx>

---
    Changes in v3:
        - Patch added. Superseed the patch "xen/passthrough: call
        arch_iommu_domain_destroy before calling iommu teardown" in
        the previous patch series.
---
 xen/arch/arm/domain.c                 | 4 ++++
 xen/drivers/passthrough/arm/iommu.c   | 1 -
 xen/drivers/passthrough/device_tree.c | 5 ++++-
 xen/include/xen/iommu.h               | 2 +-
 4 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c
index 6e56665..d85748a 100644
--- a/xen/arch/arm/domain.c
+++ b/xen/arch/arm/domain.c
@@ -772,6 +772,10 @@ int domain_relinquish_resources(struct domain *d)
     switch ( d->arch.relmem )
     {
     case RELMEM_not_started:
+        ret = iommu_release_dt_devices(d);
+        if ( ret )
+            return ret;
+
         d->arch.relmem = RELMEM_xen;
         /* Falltrough */
 
diff --git a/xen/drivers/passthrough/arm/iommu.c 
b/xen/drivers/passthrough/arm/iommu.c
index 5870aef..8223a39 100644
--- a/xen/drivers/passthrough/arm/iommu.c
+++ b/xen/drivers/passthrough/arm/iommu.c
@@ -66,7 +66,6 @@ int arch_iommu_domain_init(struct domain *d)
 
 void arch_iommu_domain_destroy(struct domain *d)
 {
-    iommu_dt_domain_destroy(d);
 }
 
 int arch_iommu_populate_page_table(struct domain *d)
diff --git a/xen/drivers/passthrough/device_tree.c 
b/xen/drivers/passthrough/device_tree.c
index 88e496e..e7eb34f 100644
--- a/xen/drivers/passthrough/device_tree.c
+++ b/xen/drivers/passthrough/device_tree.c
@@ -97,7 +97,7 @@ int iommu_dt_domain_init(struct domain *d)
     return 0;
 }
 
-void iommu_dt_domain_destroy(struct domain *d)
+int iommu_release_dt_devices(struct domain *d)
 {
     struct hvm_iommu *hd = domain_hvm_iommu(d);
     struct dt_device_node *dev, *_dev;
@@ -109,5 +109,8 @@ void iommu_dt_domain_destroy(struct domain *d)
         if ( rc )
             dprintk(XENLOG_ERR, "Failed to deassign %s in domain %u\n",
                     dt_node_full_name(dev), d->domain_id);
+        return rc;
     }
+
+    return 0;
 }
diff --git a/xen/include/xen/iommu.h b/xen/include/xen/iommu.h
index c146ee4..d03df14 100644
--- a/xen/include/xen/iommu.h
+++ b/xen/include/xen/iommu.h
@@ -117,7 +117,7 @@ void iommu_read_msi_from_ire(struct msi_desc *msi_desc, 
struct msi_msg *msg);
 int iommu_assign_dt_device(struct domain *d, struct dt_device_node *dev);
 int iommu_deassign_dt_device(struct domain *d, struct dt_device_node *dev);
 int iommu_dt_domain_init(struct domain *d);
-void iommu_dt_domain_destroy(struct domain *d);
+int iommu_release_dt_devices(struct domain *d);
 
 #endif /* HAS_DEVICE_TREE */
 
-- 
2.1.4


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel