[01/23] iommu: Pull IOVA cookie management into the core

Commit Message

Robin Murphy July 21, 2021, 6:20 p.m. UTC

Now that everyone has converged on iommu-dma for IOMMU_DOMAIN_DMA
support, we can abandon the notion of drivers being responsible for the
cookie type, and consolidate all the management into the core code.

Signed-off-by: Robin Murphy <[e-mail]>
---
 drivers/iommu/iommu.c | 7 +++++++
 include/linux/iommu.h | 3 ++-
 2 files changed, 9 insertions(+), 1 deletion(-)

Patch

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 5419c4b9f27a..0952de57c466 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -7,6 +7,7 @@ 
 #define pr_fmt(fmt)    "iommu: " fmt
 
 #include <linux/device.h>
+#include <linux/dma-iommu.h>
 #include <linux/kernel.h>
 #include <linux/bug.h>
 #include <linux/types.h>
@@ -1941,6 +1942,11 @@  static struct iommu_domain *__iommu_domain_alloc(struct bus_type *bus,
 	/* Assume all sizes by default; the driver may override this later */
 	domain->pgsize_bitmap  = bus->iommu_ops->pgsize_bitmap;
 
+	/* Temporarily ignore -EEXIST while drivers still get their own cookies */
+	if (type == IOMMU_DOMAIN_DMA && iommu_get_dma_cookie(domain) == -ENOMEM) {
+		iommu_domain_free(domain);
+		domain = NULL;
+	}
 	return domain;
 }
 
@@ -1952,6 +1958,7 @@  EXPORT_SYMBOL_GPL(iommu_domain_alloc);
 
 void iommu_domain_free(struct iommu_domain *domain)
 {
+	iommu_put_dma_cookie(domain);
 	domain->ops->domain_free(domain);
 }
 EXPORT_SYMBOL_GPL(iommu_domain_free);
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 32d448050bf7..007662b65474 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -40,6 +40,7 @@  struct iommu_domain;
 struct notifier_block;
 struct iommu_sva;
 struct iommu_fault_event;
+struct iommu_dma_cookie;
 
 /* iommu fault flags */
 #define IOMMU_FAULT_READ	0x0
@@ -86,7 +87,7 @@  struct iommu_domain {
 	iommu_fault_handler_t handler;
 	void *handler_token;
 	struct iommu_domain_geometry geometry;
-	void *iova_cookie;
+	struct iommu_dma_cookie *iova_cookie;
 };
 
 enum iommu_cap {