iommu/ipmmu-vmsa: Unify domain alloc/free

We have two implementations for ipmmu_ops->alloc depending on
CONFIG_IOMMU_DMA, the difference being whether they accept the
IOMMU_DOMAIN_DMA type or not. However, iommu_dma_get_cookie() is
guaranteed to return an error when !CONFIG_IOMMU_DMA, so if
ipmmu_domain_alloc_dma() was actually checking and handling the return
value correctly, it would behave the same as ipmmu_domain_alloc()
anyway.

Similarly for freeing; iommu_put_dma_cookie() is robust by design.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
index 00e88a8..3715407 100644 (file)
--- a/drivers/iommu/ipmmu-vmsa.c
+++ b/drivers/iommu/ipmmu-vmsa.c
@@ -528,6 +528,27 @@ static struct iommu_domain *__ipmmu_domain_alloc(unsigned type)
        return &domain->io_domain;
 }
 
+static struct iommu_domain *ipmmu_domain_alloc(unsigned type)
+{
+       struct iommu_domain *io_domain = NULL;
+
+       switch (type) {
+       case IOMMU_DOMAIN_UNMANAGED:
+               io_domain = __ipmmu_domain_alloc(type);
+               break;
+
+       case IOMMU_DOMAIN_DMA:
+               io_domain = __ipmmu_domain_alloc(type);
+               if (io_domain && iommu_get_dma_cookie(io_domain)) {
+                       kfree(io_domain);
+                       io_domain = NULL;
+               }
+               break;
+       }
+
+       return io_domain;
+}
+
 static void ipmmu_domain_free(struct iommu_domain *io_domain)
 {
        struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
@@ -536,6 +557,7 @@ static void ipmmu_domain_free(struct iommu_domain *io_domain)
         * Free the domain resources. We assume that all devices have already
         * been detached.
         */
+       iommu_put_dma_cookie(io_domain);
        ipmmu_domain_destroy_context(domain);
        free_io_pgtable_ops(domain->iop);
        kfree(domain);
@@ -671,14 +693,6 @@ static int ipmmu_of_xlate(struct device *dev,
 
 #if defined(CONFIG_ARM) && !defined(CONFIG_IOMMU_DMA)
 
-static struct iommu_domain *ipmmu_domain_alloc(unsigned type)
-{
-       if (type != IOMMU_DOMAIN_UNMANAGED)
-               return NULL;
-
-       return __ipmmu_domain_alloc(type);
-}
-
 static int ipmmu_add_device(struct device *dev)
 {
        struct ipmmu_vmsa_device *mmu = NULL;
@@ -779,37 +793,6 @@ static const struct iommu_ops ipmmu_ops = {
 static DEFINE_SPINLOCK(ipmmu_slave_devices_lock);
 static LIST_HEAD(ipmmu_slave_devices);
 
-static struct iommu_domain *ipmmu_domain_alloc_dma(unsigned type)
-{
-       struct iommu_domain *io_domain = NULL;
-
-       switch (type) {
-       case IOMMU_DOMAIN_UNMANAGED:
-               io_domain = __ipmmu_domain_alloc(type);
-               break;
-
-       case IOMMU_DOMAIN_DMA:
-               io_domain = __ipmmu_domain_alloc(type);
-               if (io_domain)
-                       iommu_get_dma_cookie(io_domain);
-               break;
-       }
-
-       return io_domain;
-}
-
-static void ipmmu_domain_free_dma(struct iommu_domain *io_domain)
-{
-       switch (io_domain->type) {
-       case IOMMU_DOMAIN_DMA:
-               iommu_put_dma_cookie(io_domain);
-               /* fall-through */
-       default:
-               ipmmu_domain_free(io_domain);
-               break;
-       }
-}
-
 static int ipmmu_add_device_dma(struct device *dev)
 {
        struct iommu_group *group;
@@ -878,8 +861,8 @@ static struct iommu_group *ipmmu_find_group_dma(struct device *dev)
 }
 
 static const struct iommu_ops ipmmu_ops = {
-       .domain_alloc = ipmmu_domain_alloc_dma,
-       .domain_free = ipmmu_domain_free_dma,
+       .domain_alloc = ipmmu_domain_alloc,
+       .domain_free = ipmmu_domain_free,
        .attach_dev = ipmmu_attach_device,
        .detach_dev = ipmmu_detach_device,
        .map = ipmmu_map,