[RFC PATCH v2 16/19] RDMA/uverbs: Add back pointer to system file object

[ira . weiny]

From: Ira Weiny <ira.weiny@xxxxxxxxx>

In order for MRs to be tracked against the open verbs context the ufile
needs to have a pointer to hand to the GUP code.

No references need to be taken as this should be valid for the lifetime
of the context.

Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
---
 drivers/infiniband/core/uverbs.h      | 1 +
 drivers/infiniband/core/uverbs_main.c | 1 +
 2 files changed, 2 insertions(+)

diff --git a/drivers/infiniband/core/uverbs.h b/drivers/infiniband/core/uverbs.h
index 1e5aeb39f774..e802ba8c67d6 100644
--- a/drivers/infiniband/core/uverbs.h
+++ b/drivers/infiniband/core/uverbs.h
@@ -163,6 +163,7 @@ struct ib_uverbs_file {
 	struct page *disassociate_page;
 
 	struct xarray		idr;
+	struct file             *sys_file; /* backpointer to system file object */
 };
 
 struct ib_uverbs_event {
diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c
index 11c13c1381cf..002c24e0d4db 100644
--- a/drivers/infiniband/core/uverbs_main.c
+++ b/drivers/infiniband/core/uverbs_main.c
@@ -1092,6 +1092,7 @@ static int ib_uverbs_open(struct inode *inode, struct file *filp)
 	INIT_LIST_HEAD(&file->umaps);
 
 	filp->private_data = file;
+	file->sys_file = filp;
 	list_add_tail(&file->list, &dev->uverbs_file_list);
 	mutex_unlock(&dev->lists_mutex);
 	srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
-- 
2.20.1