RDMA/ocrdma: Dont use PD 0 for userpace CQ DB

Create_CQ verb doesn't provide a PD pointer.  So, until now we are
creating all (both userspace and kernel) CQ DB regions from PD0.  This
will result in mmapping PD0 to applications.  A rogue userspace
application can mess things up.

Also more serious issues is even the be2net NIC uses PD0.

This patch addresses this problem by:

1) Create a PD page for every userspace application when the
   alloc_ucontext is called. This will be destroyed in
   dealloc_ucontext.
2) All CQs for that context will use the PD allocated in ucontext.
3) The first create_PD call from application will result in returning
   the PD address from its ucontext (no new PD will be created).
4) For subsecquent create_pd calls from application, we create new PDs for
   the application.

Signed-off-by: Naresh Gottumukkala <bgottumukkala@emulex.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/ocrdma/ocrdma.h b/drivers/infiniband/hw/ocrdma/ocrdma.h
index 1c8ba4cefcba..fde8fb097a8c 100644
--- a/drivers/infiniband/hw/ocrdma/ocrdma.h
+++ b/drivers/infiniband/hw/ocrdma/ocrdma.h
@@ -324,6 +324,9 @@ struct ocrdma_ucontext {
 
 	struct list_head mm_head;
 	struct mutex mm_list_lock; /* protects list entries of mm type */
+	struct ocrdma_pd *cntxt_pd;
+	int pd_in_use;
+
 	struct {
 		u32 *va;
 		dma_addr_t pa;