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>

1 files changed, 24 insertions, 41 deletions

diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
index 00e88a88ee3a..37154075c00a 100644
--- 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,