iommu: Merge iopf_device_param into iommu_fault_param

The struct dev_iommu contains two pointers, fault_param and iopf_param.
The fault_param pointer points to a data structure that is used to store
pending faults that are awaiting responses. The iopf_param pointer points
to a data structure that is used to store partial faults that are part of
a Page Request Group.

The fault_param and iopf_param pointers are essentially duplicate. This
causes memory waste. Merge the iopf_device_param pointer into the
iommu_fault_param pointer to consolidate the code and save memory. The
consolidated pointer would be allocated on demand when the device driver
enables the iopf on device, and would be freed after iopf is disabled.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Tested-by: Yan Zhao <yan.y.zhao@intel.com>
Tested-by: Longfang Liu <liulongfang@huawei.com>
Link: https://lore.kernel.org/r/20240212012227.119381-6-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

1 files changed, 14 insertions, 4 deletions

diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 829bcb5a8e23..bbb7c2ad5184 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -42,6 +42,7 @@ struct notifier_block;
 struct iommu_sva;
 struct iommu_fault_event;
 struct iommu_dma_cookie;
+struct iopf_queue;
 
 #define IOMMU_FAULT_PERM_READ	(1 << 0) /* read */
 #define IOMMU_FAULT_PERM_WRITE	(1 << 1) /* write */
@@ -672,21 +673,31 @@ struct iommu_fault_event {
  * struct iommu_fault_param - per-device IOMMU fault data
  * @handler: Callback function to handle IOMMU faults at device level
  * @data: handler private data
- * @faults: holds the pending faults which needs response
  * @lock: protect pending faults list
+ * @dev: the device that owns this param
+ * @queue: IOPF queue
+ * @queue_list: index into queue->devices
+ * @partial: faults that are part of a Page Request Group for which the last
+ *           request hasn't been submitted yet.
+ * @faults: holds the pending faults which need response
  */
 struct iommu_fault_param {
 	iommu_dev_fault_handler_t handler;
 	void *data;
-	struct list_head faults;
 	struct mutex lock;
+
+	struct device *dev;
+	struct iopf_queue *queue;
+	struct list_head queue_list;
+
+	struct list_head partial;
+	struct list_head faults;
 };
 
 /**
  * struct dev_iommu - Collection of per-device IOMMU data
  *
  * @fault_param: IOMMU detected device fault reporting data
- * @iopf_param:	 I/O Page Fault queue and data
  * @fwspec:	 IOMMU fwspec data
  * @iommu_dev:	 IOMMU device this device is linked to
  * @priv:	 IOMMU Driver private data
@@ -702,7 +713,6 @@ struct iommu_fault_param {
 struct dev_iommu {
 	struct mutex lock;
 	struct iommu_fault_param	*fault_param;
-	struct iopf_device_param	*iopf_param;
 	struct iommu_fwspec		*fwspec;
 	struct iommu_device		*iommu_dev;
 	void				*priv;