IB/uverbs: Allow resize CQ operation to return driver-specific data

Add a ib_uverbs_resize_cq_resp.driver_data field so that low-level
drivers can return data from a resize CQ operation to userspace.  Have
ib_uverbs_resize_cq() only copy the cqe field, to avoid having to bump
the userspace ABI.

Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

2 files changed, 3 insertions, 2 deletions

diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index 8b6df7cec0bf..deae43f31e79 100644
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -879,11 +879,10 @@ ssize_t ib_uverbs_resize_cq(struct ib_uverbs_file *file,
         if (ret)
                 goto out;
 
-        memset(&resp, 0, sizeof resp);
         resp.cqe = cq->cqe;
 
         if (copy_to_user((void __user *) (unsigned long) cmd.response,
-                         &resp, sizeof resp))
+                         &resp, sizeof resp.cqe))
                 ret = -EFAULT;
 
 out:
diff --git a/include/rdma/ib_user_verbs.h b/include/rdma/ib_user_verbs.h
index 7b5372010f4b..db1b814b62cc 100644
--- a/include/rdma/ib_user_verbs.h
+++ b/include/rdma/ib_user_verbs.h
@@ -275,6 +275,8 @@ struct ib_uverbs_resize_cq {
 
 struct ib_uverbs_resize_cq_resp {
         __u32 cqe;
+        __u32 reserved;
+        __u64 driver_data[0];
 };
 
 struct ib_uverbs_poll_cq {