From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [PATCH] RDMA/cxgb4: Add default_llseek to debugfs files. Date: Wed, 29 Sep 2010 21:17:54 +0200 Message-ID: <201009292117.54828.arnd@arndb.de> References: <20100929141112.26944.21931.stgit@build.ogc.int> Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Roland Dreier Cc: Steve Wise , linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-next-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-rdma@vger.kernel.org On Wednesday 29 September 2010 19:19:32 Roland Dreier wrote: > > @@ -182,6 +182,7 @@ static const struct file_operations qp_debugfs_fops = { > > .open = qp_open, > > .release = qp_release, > > .read = debugfs_read, > > + .llseek = default_llseek, > > }; > > I think this could actually be generic_file_llseek (right, Arnd?). The main difference between default_llseek and generic_file_llseek is that default_llseek doesn't care about the maximum file size of the underlying file system, which is ULONG_MAX on debugfs, so they are equivalent. In general, the preferred one is no_llseek for those files where you know you do not need to seek. If you do, I'd use default_llseek for character devices and generic_file_llseek for file systems that set the s_maxbytes. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html