[openib-general] RE: [PATCH 3 of 3] mad: large RMPP support, Round 2

[Sean Hefty]

> I did it this way to avoid using kzalloc for all segment allocations, or
> kmalloc/memset for all.  This way, only the last segment is "memset"'ed
> and only in the padding area.

The API states that the buffer returned from ib_create_send_mad will be cleared. 
  We either need to clear the buffer, or update the documentation.

> [JPM]: This was done to hide segment implementation details from the
> user_mad layer. You are correct that we can get rid of the size field,
> and store it only once.
> However, I think that the proper place for this value is the
> "ib_mad_send_wr_private" structure, which also holds the list pointer.
> How about if we change 
> struct ib_mad_multipacket_seg
> *ib_mad_get_multipacket_seg(struct ib_mad_send_buf *send_buf, int
> seg_num)
> 
> to also return the segment size:

Since the user needs to know the segment size, it makes more sense to me to just 
expose it through ib_mad_send_buf.

> [JPM]:  You are correct.  In fact, the test just before this one is also
> performed in ib_create_send_mad(), and may also be deleted (this was not
> part of the patch):
> 
> 	if (rmpp_active && !agent->rmpp_version) {
> 		ret = -EINVAL;
> 		goto err_ah;
> 	}

I will remove these, and submit a patch for any other changes.  Thanks.

- Sean