From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: Re: [RFC] Netlink and user-space buffer pointers Date: Wed, 19 Apr 2006 09:26:45 -0700 Message-ID: <20060419092645.29cb0420@localhost.localdomain> References: <1145306661.4151.0.camel@localhost.localdomain> <20060418160121.GA2707@us.ibm.com> <444633B5.5030208@emulex.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: linux-scsi@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Return-path: To: James.Smart@Emulex.Com In-Reply-To: <444633B5.5030208@emulex.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Wed, 19 Apr 2006 08:57:25 -0400 James Smart wrote: > Folks, > > To take netlink to where we want to use it within the SCSI subsystem (as > the mechanism of choice to replace ioctls), we're going to need to pass > user-space buffer pointers. This changes the design of netlink. It is desired that netlink can be done remotely over the network as well as queueing. The current design is message based, not RPC based. By including a user-space pointer, you are making the message dependent on the context as it is process. Please rethink your design. > What is the best, portable manner to pass a pointer between user and kernel > space within a netlink message ? The example I've seen is in the iscsi > target code - and it's passed between user-kernel space as a u64, then > typecast to a void *, and later within the bio_map_xxx functions, as an > unsigned long. I assume we are going to continue with this method ? > > -- james s > - > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html