From 02d1aa7af17ef0e0655745ce32cab369ed040a67 Mon Sep 17 00:00:00 2001
From: Eli Cohen <eli@mellanox.com>
Date: Sun, 8 Feb 2015 13:28:50 +0200
Subject: 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.
Following the discussion about this patch [1], the code now validates
the command's comp_mask is zero, returning -EINVAL for unknown values,
in order to allow extending the verb in the future.
The verb also checks the user-space provided response buffer size and
only fills in capabilities that will fit in the buffer. In attempt to
follow the spirit of presentation [2] by Tzahi Oved that was presented
during OpenFabrics Alliance International Developer Workshop 2013, the
comp_mask bits will only describe which fields are valid. Furthermore,
fields that can simply be cleared when they are not supported, do not
require a comp_mask bit at all. The verb returns a response_length
field containing the actual number of bytes written by the kernel, so
that a newer version running on an older kernel can tell which fields
were actually returned.
[1] [PATCH v1 0/5] IB/core: extended query device caps cleanup for v3.19
http://thread.gmane.org/gmane.linux.kernel.api/7889/
[2] https://www.openfabrics.org/images/docs/2013_Dev_Workshop/Tues_0423/2013_Workshop_Tues_0830_Tzahi_Oved-verbs_extensions_ofa_2013-tzahio.pdf
Signed-off-by: Eli Cohen <eli@mellanox.com>
Signed-off-by: Haggai Eran <haggaie@mellanox.com>
Reviewed-by: Yann Droneaud <ydroneaud@opteya.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
---
include/uapi/rdma/ib_user_verbs.h | 12 ++++++++++++
1 file changed, 12 insertions(+)
(limited to 'include')
diff --git a/include/uapi/rdma/ib_user_verbs.h b/include/uapi/rdma/ib_user_verbs.h
index 867cc5084afb..f0f799afd856 100644
--- a/include/uapi/rdma/ib_user_verbs.h
+++ b/include/uapi/rdma/ib_user_verbs.h
@@ -90,6 +90,7 @@ 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,
};
@@ -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 response_length;
+};
+
struct ib_uverbs_query_port {
__u64 response;
__u8 port_num;
--
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