From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kent Overstreet Subject: Re: bcachefs xattr Date: Wed, 12 Aug 2015 23:50:49 -0800 Message-ID: <20150813075049.GB14629@moria.home.lan> References: <1439451547.5775.9.camel@hasee> <20150813074123.GA14629@moria.home.lan> <1439452153.21532.2.camel@hasee> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pa0-f54.google.com ([209.85.220.54]:34663 "EHLO mail-pa0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751740AbbHMHux (ORCPT ); Thu, 13 Aug 2015 03:50:53 -0400 Received: by pawu10 with SMTP id u10so32645203paw.1 for ; Thu, 13 Aug 2015 00:50:53 -0700 (PDT) Content-Disposition: inline In-Reply-To: <1439452153.21532.2.camel@hasee> Sender: linux-bcache-owner@vger.kernel.org List-Id: linux-bcache@vger.kernel.org To: Ming Lin Cc: linux-bcache@vger.kernel.org On Thu, Aug 13, 2015 at 12:49:13AM -0700, Ming Lin wrote: > On Wed, 2015-08-12 at 23:41 -0800, Kent Overstreet wrote: > > On Thu, Aug 13, 2015 at 12:39:07AM -0700, Ming Lin wrote: > > > Hi Kent, > > > > > > Seems the max length of xattr name+value is only 2004 bytes. > > > Why the limit of U8_MAX below? > > > > The size of the key and value is stored as a u8 in units of u64s - the u64s > > field of struct bkey. > > xfstests/generic/020 failed. > Got it now. > > xfs supports 64KB values. > In order to support larger size of value, does it make sense to store > the value in "extent"? Perhaps, but let's leave that for now and add it if there's demand for it.