Messages in this thread | | | Subject | Re: infiniband: cxgb4: GCC warnings for 32 bit | From | Paul Bolle <> | Date | Tue, 05 Feb 2013 17:36:56 +0100 |
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On Tue, 2013-02-05 at 09:46 -0600, Steve Wise wrote: > On 2/5/2013 4:15 AM, Paul Bolle wrote: > > And why is 'cookie' __u64? Is struct cpl_fw6_msg_ofld_connection_wr_rpl > > used in userspace code? Can't 'cookie' be of type "struct sk_buff *"? Is > > there a requirement for it to be 64 bits wide on both 32 bit and 64 bit? > > In general, these fields are __ types to highlight the fact that they > define an interface between the host driver and adapter firmware.
That's something new for me. Is that a custom for infiniband drivers or is it used throughout the tree?
> These > "cookie" fields are opaque to the firmware. They are passed to firmware > in a work request and then reflected back to the host in the reply to > the work request. Given this, I think there are two issues: > > 1) no swapping is really needed. The values are opaque to firmware, and > thus can stay in host byte order. > > 2) to remove the warning, we need something like: > > req->cookie = (unsigned long)skb; > > and > > rpl_skb = (struct sk_buff *)(unsigned long)req->cookie;
That's is exactly what I came up with to silence these warnings. But I didn't dare to submit it because I was too puzzled with the current code. Anyhow, should I submit the (trivial) patch to fix this?
Paul Bolle
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