msm: iommu: Check if device is already attached
An IOMMU device can only be attached to one IOMMU domain at
any given time. Check whether the device is already
attached to a domain before allowing it to be attached to
another domain. If so, return busy.
Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org>
Signed-off-by: Daniel Walker <dwalker@codeaurora.org>
diff --git a/arch/arm/mach-msm/iommu.c b/arch/arm/mach-msm/iommu.c
index 74f2157..67e8f53 100644
--- a/arch/arm/mach-msm/iommu.c
+++ b/arch/arm/mach-msm/iommu.c
@@ -241,6 +241,11 @@
goto fail;
}
+ if (!list_empty(&ctx_drvdata->attached_elm)) {
+ ret = -EBUSY;
+ goto fail;
+ }
+
list_for_each_entry(tmp_drvdata, &priv->list_attached, attached_elm)
if (tmp_drvdata == ctx_drvdata) {
ret = -EBUSY;