From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Whitney Subject: Re: [PATCH] mke2fs: clarify inline data inode size error message Date: Wed, 1 Oct 2014 16:36:17 -0400 Message-ID: <20141001203616.GA2860@wallace> References: <20140927155515.GA2322@wallace> <20140929055350.GL10150@birch.djwong.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Eric Whitney , linux-ext4@vger.kernel.org, tytso@mit.edu To: "Darrick J. Wong" Return-path: Received: from mail-qa0-f52.google.com ([209.85.216.52]:48543 "EHLO mail-qa0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752103AbaJAUgV (ORCPT ); Wed, 1 Oct 2014 16:36:21 -0400 Received: by mail-qa0-f52.google.com with SMTP id dc16so866883qab.25 for ; Wed, 01 Oct 2014 13:36:20 -0700 (PDT) Content-Disposition: inline In-Reply-To: <20140929055350.GL10150@birch.djwong.org> Sender: linux-ext4-owner@vger.kernel.org List-ID: * Darrick J. Wong : > On Sat, Sep 27, 2014 at 11:55:15AM -0400, Eric Whitney wrote: > > The existing error message can be made more helpful by more clearly > > implying the attempt to make a file system with undersized inodes is > > failing and suggesting a corrective action. > > > > Signed-off-by: Eric Whitney > > --- > > misc/mke2fs.c | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/misc/mke2fs.c b/misc/mke2fs.c > > index 2bc435b..00bb00d 100644 > > --- a/misc/mke2fs.c > > +++ b/misc/mke2fs.c > > @@ -2358,7 +2358,8 @@ profile_error: > > EXT4_FEATURE_INCOMPAT_INLINE_DATA) && > > fs_param.s_inode_size == EXT2_GOOD_OLD_INODE_SIZE) { > > com_err(program_name, 0, > > - _("inode size is %d, inline data is useless"), > > + _("%d byte inodes are too small for inline data; " > > + "specify larger size"), > > How much larger? The next larger inode size is 256 bytes, so we ought to tell > the user that. ("specify a size at least 256 bytes"?) > > --D I'd be fine with that as well. My only concern is that noting the minimum might lead to users taking that as the default when that might not best suit their needs. I thought that the reworked message I suggested might send them off to the mke2fs man page, where it's at least clear the legal sizes are powers of 2 greater than 128 bytes. However, we don't seem to have published any useful guidelines regarding inode size selection when building a file system supporting inline data. Your inline data notes on the wiki are about as good as we've got, unless I've missed something, and I think we'd want a little more addressing inode size tradeoffs. I wonder if Zheng has anything relevant we can use to improve the manpages? Again, if an error message specifying the minimum or say, a range from minimum to maximum suggested is preferred, I'd be happy to post another patch. Thanks, Eric > > > fs_param.s_inode_size); > > exit(1); > > } > > -- > > 1.9.1 > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html