From 02d1aa7af17ef0e0655745ce32cab369ed040a67 Mon Sep 17 00:00:00 2001 From: Eli Cohen 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 Signed-off-by: Haggai Eran Reviewed-by: Yann Droneaud Signed-off-by: Roland Dreier --- drivers/infiniband/core/uverbs_main.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/infiniband/core/uverbs_main.c') diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c index 5db1a8cc388d..259dcc7779f5 100644 --- a/drivers/infiniband/core/uverbs_main.c +++ b/drivers/infiniband/core/uverbs_main.c @@ -123,6 +123,7 @@ static int (*uverbs_ex_cmd_table[])(struct ib_uverbs_file *file, struct ib_udata *uhw) = { [IB_USER_VERBS_EX_CMD_CREATE_FLOW] = ib_uverbs_ex_create_flow, [IB_USER_VERBS_EX_CMD_DESTROY_FLOW] = ib_uverbs_ex_destroy_flow, + [IB_USER_VERBS_EX_CMD_QUERY_DEVICE] = ib_uverbs_ex_query_device, }; static void ib_uverbs_add_one(struct ib_device *device); -- cgit v1.2.3