From mboxrd@z Thu Jan 1 00:00:00 1970 From: Li Zefan Subject: Re: [PATCH] Btrfs: use the normal checksumming infrastructure for free space cache Date: Mon, 13 Jun 2011 10:10:04 +0800 Message-ID: <4DF5717C.2080700@cn.fujitsu.com> References: <1307734827-10697-1-git-send-email-josef@redhat.com> <4DF56D60.4070208@cn.fujitsu.com> <1307929964-sup-6781@shiny> <4DF57065.3090109@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: Josef Bacik , linux-btrfs To: Chris Mason Return-path: In-Reply-To: <4DF57065.3090109@cn.fujitsu.com> List-ID: Li Zefan wrote: > Chris Mason wrote: >> Excerpts from Li Zefan's message of 2011-06-12 21:52:32 -0400: >>> Josef Bacik wrote: >>>> We used to store the checksums of the space cache directly in the space cache, >>>> however that doesn't work out too well if we have more space than we can fit the >>>> checksums into the first page. So instead use the normal checksumming >>>> infrastructure. There were problems with doing this originally but those >>>> problems don't exist now so this works out fine. Thanks, >>>> >>> >>> This looks great, so I'll drop my patch that extends the original code to >>> allow more than 1 crc page. >> >> I do like them a lot, but what happens when a special case crc kernel >> mounts a free space cache created by this patch? >> > > So we need a check, like the one in load_free_space_cache(): > oh I misunderstood your question..