From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chao Yu Subject: Re: [PATCH] f2fs: do not trim preallocated blocks when truncating after i_size Date: Tue, 09 Jun 2015 10:22:49 +0800 Message-ID: <007a01d0a25b$4dbb2b60$e9318220$@samsung.com> References: <000101d09f7b$4a2559e0$de700da0$@samsung.com> <20150608180643.GA59258@jaegeuk-mac02.mot.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from sog-mx-4.v43.ch3.sourceforge.com ([172.29.43.194] helo=mx.sourceforge.net) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1Z29Cj-0004td-UJ for linux-f2fs-devel@lists.sourceforge.net; Tue, 09 Jun 2015 02:23:53 +0000 Received: from mailout4.samsung.com ([203.254.224.34]) by sog-mx-4.v43.ch3.sourceforge.com with esmtps (TLSv1:AES128-SHA:128) (Exim 4.76) id 1Z29Ci-0005ks-4l for linux-f2fs-devel@lists.sourceforge.net; Tue, 09 Jun 2015 02:23:53 +0000 Received: from epcpsbgm2.samsung.com (epcpsbgm2 [203.254.230.27]) by mailout4.samsung.com (Oracle Communications Messaging Server 7.0.5.31.0 64bit (built May 5 2014)) with ESMTP id <0NPN03175NZKAH20@mailout4.samsung.com> for linux-f2fs-devel@lists.sourceforge.net; Tue, 09 Jun 2015 11:23:44 +0900 (KST) In-reply-to: <20150608180643.GA59258@jaegeuk-mac02.mot.com> Content-language: zh-cn List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net To: 'Jaegeuk Kim' Cc: linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net > -----Original Message----- > From: Jaegeuk Kim [mailto:jaegeuk@kernel.org] > Sent: Tuesday, June 09, 2015 2:07 AM > To: Chao Yu > Cc: linux-f2fs-devel@lists.sourceforge.net; linux-kernel@vger.kernel.org > Subject: Re: [PATCH] f2fs: do not trim preallocated blocks when truncating after i_size > > On Fri, Jun 05, 2015 at 06:34:02PM +0800, Chao Yu wrote: > > When we perform generic/092 in xfstests, output is like below: > > > > XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) > > 0: [0..10239]: data > > 0: [0..10239]: data > > -1: [10240..20479]: unwritten > > +1: [10240..14335]: unwritten > > > > This is because with this testcase, we redefine the regulation for > > truncate in perallocated space past i_size as below: > > > > "There was some confused about what the fs was supposed to do when you > > truncate at i_size with preallocated space past i_size. We decided on the > > following things. > > > > 1) truncate(i_size) will trim all blocks past i_size. > > 2) truncate(x) where x > i_size will not trim all blocks past i_size. > > " > > > > This method is used in xfs, and then ext4/btrfs will follow the rule. > > > > This patch fixes to follow the new rule for f2fs. > > > > Signed-off-by: Chao Yu > > --- > > fs/f2fs/file.c | 8 ++++---- > > 1 file changed, 4 insertions(+), 4 deletions(-) > > > > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c > > index 4d42d66..85f97af 100644 > > --- a/fs/f2fs/file.c > > +++ b/fs/f2fs/file.c > > @@ -651,16 +651,16 @@ int f2fs_setattr(struct dentry *dentry, struct iattr *attr) > > f2fs_get_encryption_info(inode)) > > return -EACCES; > > > > - if (attr->ia_size != i_size_read(inode)) { > > + if (attr->ia_size <= i_size_read(inode)) { > > truncate_setsize(inode, attr->ia_size); > > f2fs_truncate(inode); > > f2fs_balance_fs(F2FS_I_SB(inode)); > > } else { > > /* > > - * giving a chance to truncate blocks past EOF which > > - * are fallocated with FALLOC_FL_KEEP_SIZE. > > + * do not trim all blocks after i_size if target size is > > + * larger than i_size. > > */ > > - f2fs_truncate(inode); > > + truncate_setsize(inode, attr->ia_size); > > So, we can do: > truncate_setsize(); > > if (attr->ia_size <= i_size_read(inode)) { > f2fs_truncate(inode); > f2fs_balance_fs(); > } > > Right? Yes, let me fix and resend the patch. Thanks, > > > } > > } > > > > -- > > 2.4.2 ------------------------------------------------------------------------------