IB/core: Add support for extended query device caps

Add extensible query device capabilities verb to allow adding new features.
ib_uverbs_ex_query_device is added and copy_query_dev_fields is used to
copy capability fields to be used by both ib_uverbs_query_device and
ib_uverbs_ex_query_device.

Signed-off-by: Eli Cohen <eli@mellanox.com>
Signed-off-by: Haggai Eran <haggaie@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

2 files changed, 17 insertions, 2 deletions

diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 470a011d6fa4..97a999f9e4d8 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -1662,7 +1662,10 @@ static inline int ib_copy_from_udata(void *dest, struct ib_udata *udata, size_t
 
 static inline int ib_copy_to_udata(struct ib_udata *udata, void *src, size_t len)
 {
-        return copy_to_user(udata->outbuf, src, len) ? -EFAULT : 0;
+        size_t copy_sz;
+
+        copy_sz = min_t(size_t, len, udata->outlen);
+        return copy_to_user(udata->outbuf, src, copy_sz) ? -EFAULT : 0;
 }
 
 /**
diff --git a/include/uapi/rdma/ib_user_verbs.h b/include/uapi/rdma/ib_user_verbs.h
index 26daf55ff76e..e8a96071e352 100644
--- a/include/uapi/rdma/ib_user_verbs.h
+++ b/include/uapi/rdma/ib_user_verbs.h
@@ -90,8 +90,9 @@ enum {
 };
 
 enum {
+        IB_USER_VERBS_EX_CMD_QUERY_DEVICE = IB_USER_VERBS_CMD_QUERY_DEVICE,
         IB_USER_VERBS_EX_CMD_CREATE_FLOW = IB_USER_VERBS_CMD_THRESHOLD,
-        IB_USER_VERBS_EX_CMD_DESTROY_FLOW
+        IB_USER_VERBS_EX_CMD_DESTROY_FLOW,
 };
 
 /*
@@ -201,6 +202,17 @@ struct ib_uverbs_query_device_resp {
         __u8  reserved[4];
 };
 
+struct ib_uverbs_ex_query_device {
+        __u32 comp_mask;
+        __u32 reserved;
+};
+
+struct ib_uverbs_ex_query_device_resp {
+        struct ib_uverbs_query_device_resp base;
+        __u32 comp_mask;
+        __u32 reserved;
+};
+
 struct ib_uverbs_query_port {
         __u64 response;
         __u8  port_num;