From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 317EEC38BFA for ; Mon, 24 Feb 2020 21:46:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EC84D2176D for ; Mon, 24 Feb 2020 21:46:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582580769; bh=z1i6mPyjX9QN96QoVDwIkGCue6T+aiaxeFUnXYRrfi8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=0T3p7+96Fd6obLaXwjMc8+BOqFNZ1aDMk0DM/eNIRaNzOORSoOJdegfTwjf1t/py3 QWbPCXIf3kgIEmH6nGdKCu0SOlT71Kr1ZHKObvfjOEru5y4DQ2Sp56xN0mS2mVoY2s 13bBhnwDTJTtVJlxhvwJXmdmVdf8IV+FSy2s7Ylg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727978AbgBXVqH (ORCPT ); Mon, 24 Feb 2020 16:46:07 -0500 Received: from mail.kernel.org ([198.145.29.99]:56964 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726980AbgBXVqH (ORCPT ); Mon, 24 Feb 2020 16:46:07 -0500 Received: from localhost (unknown [104.132.1.66]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D502C21556; Mon, 24 Feb 2020 21:46:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582580765; bh=z1i6mPyjX9QN96QoVDwIkGCue6T+aiaxeFUnXYRrfi8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=dqP6l2T/2FIUunzolALuF9clQGvFZOXhCelT8Qin4TRHtDwzVCnL79h8bNf3MI8AU foTvYmuQ2pzY0ANmkJ4J3BbiF4EeAH/MZvlB2rxTeN4DmiNRs1UOslBfA7XIAArBZj p90q6kQ20jKtDJM5rZ19ddYjxYwD5Q+W+ahZLSTM= Date: Mon, 24 Feb 2020 13:46:05 -0800 From: Jaegeuk Kim To: Chao Yu Cc: linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, chao@kernel.org Subject: Re: [RFC PATCH 2/2] f2fs: introduce F2FS_IOC_RELEASE_COMPRESS_BLOCKS Message-ID: <20200224214605.GA77839@google.com> References: <20200221100922.16781-1-yuchao0@huawei.com> <20200221100922.16781-2-yuchao0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200221100922.16781-2-yuchao0@huawei.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/21, Chao Yu wrote: > There are still reserved blocks on compressed inode, this patch > introduce a new ioctl to help release reserved blocks back to > filesystem, so that userspace can reuse those freed space. I thought we can add compressed_blocks into free space, after converting the file to immutable one. Otherwise, this patch is able to corrupt the filesystem very easily. > > Signed-off-by: Chao Yu > --- > fs/f2fs/f2fs.h | 6 +++ > fs/f2fs/file.c | 129 ++++++++++++++++++++++++++++++++++++++++++++++++- > 2 files changed, 134 insertions(+), 1 deletion(-) > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > index 15199df5d40a..468f807fd917 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -427,6 +427,8 @@ static inline bool __has_cursum_space(struct f2fs_journal *journal, > #define F2FS_IOC_PRECACHE_EXTENTS _IO(F2FS_IOCTL_MAGIC, 15) > #define F2FS_IOC_RESIZE_FS _IOW(F2FS_IOCTL_MAGIC, 16, __u64) > #define F2FS_IOC_GET_COMPRESS_BLOCKS _IOR(F2FS_IOCTL_MAGIC, 17, __u64) > +#define F2FS_IOC_RELEASE_COMPRESS_BLOCKS \ > + _IOR(F2FS_IOCTL_MAGIC, 18, __u64) > > #define F2FS_IOC_GET_VOLUME_NAME FS_IOC_GETFSLABEL > #define F2FS_IOC_SET_VOLUME_NAME FS_IOC_SETFSLABEL > @@ -3957,6 +3959,10 @@ static inline void f2fs_i_compr_blocks_update(struct inode *inode, > { > int diff = F2FS_I(inode)->i_cluster_size - blocks; > > + /* don't update i_compr_blocks if saved blocks were released */ > + if (!add && !F2FS_I(inode)->i_compr_blocks) > + return; > + > if (add) { > F2FS_I(inode)->i_compr_blocks += diff; > stat_add_compr_blocks(inode, diff); > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c > index 235708c892af..613f87151d90 100644 > --- a/fs/f2fs/file.c > +++ b/fs/f2fs/file.c > @@ -557,6 +557,7 @@ void f2fs_truncate_data_blocks_range(struct dnode_of_data *dn, int count) > bool compressed_cluster = false; > int cluster_index = 0, valid_blocks = 0; > int cluster_size = F2FS_I(dn->inode)->i_cluster_size; > + bool released = !F2FS_I(dn->inode)->i_compr_blocks; > > if (IS_INODE(dn->node_page) && f2fs_has_extra_attr(dn->inode)) > base = get_extra_isize(dn->inode); > @@ -595,7 +596,9 @@ void f2fs_truncate_data_blocks_range(struct dnode_of_data *dn, int count) > clear_inode_flag(dn->inode, FI_FIRST_BLOCK_WRITTEN); > > f2fs_invalidate_blocks(sbi, blkaddr); > - nr_free++; > + > + if (released && blkaddr != COMPRESS_ADDR) > + nr_free++; > } > > if (compressed_cluster) > @@ -3416,6 +3419,127 @@ static int f2fs_get_compress_blocks(struct file *filp, unsigned long arg) > return put_user(blocks, (u64 __user *)arg); > } > > +static int release_compress_blocks(struct dnode_of_data *dn, pgoff_t count) > +{ > + struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode); > + unsigned int released_blocks = 0; > + int cluster_size = F2FS_I(dn->inode)->i_cluster_size; > + > + while (count) { > + int compr_blocks = 0; > + block_t blkaddr = f2fs_data_blkaddr(dn); > + int i; > + > + if (blkaddr != COMPRESS_ADDR) { > + dn->ofs_in_node += cluster_size; > + goto next; > + } > + > + for (i = 0; i < cluster_size; i++, dn->ofs_in_node++) { > + blkaddr = f2fs_data_blkaddr(dn); > + > + if (__is_valid_data_blkaddr(blkaddr)) { > + compr_blocks++; > + if (unlikely(!f2fs_is_valid_blkaddr(sbi, blkaddr, > + DATA_GENERIC_ENHANCE))) > + return -EFSCORRUPTED; > + } > + > + if (blkaddr != NEW_ADDR) > + continue; > + > + dn->data_blkaddr = NULL_ADDR; > + f2fs_set_data_blkaddr(dn); > + } > + > + f2fs_i_compr_blocks_update(dn->inode, compr_blocks, false); > + dec_valid_block_count(sbi, dn->inode, > + cluster_size - compr_blocks); > + > + released_blocks += cluster_size - compr_blocks; > +next: > + count -= cluster_size; > + } > + > + return released_blocks; > +} > + > +static int f2fs_release_compress_blocks(struct file *filp, unsigned long arg) > +{ > + struct inode *inode = file_inode(filp); > + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); > + pgoff_t page_idx = 0, last_idx; > + unsigned int released_blocks = 0; > + int ret; > + > + if (!f2fs_sb_has_compression(F2FS_I_SB(inode))) > + return -EOPNOTSUPP; > + > + if (!f2fs_compressed_file(inode)) > + return -EINVAL; > + > + if (f2fs_readonly(sbi->sb)) > + return -EROFS; > + > + ret = mnt_want_write_file(filp); > + if (ret) > + return ret; > + > + if (!F2FS_I(inode)->i_compr_blocks) > + goto out; > + > + f2fs_balance_fs(F2FS_I_SB(inode), true); > + > + inode_lock(inode); > + > + down_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]); > + down_write(&F2FS_I(inode)->i_mmap_sem); > + > + last_idx = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE); > + > + while (page_idx < last_idx) { > + struct dnode_of_data dn; > + pgoff_t end_offset, count; > + > + set_new_dnode(&dn, inode, NULL, NULL, 0); > + ret = f2fs_get_dnode_of_data(&dn, page_idx, LOOKUP_NODE); > + if (ret) { > + if (ret == -ENOENT) { > + page_idx = f2fs_get_next_page_offset(&dn, > + page_idx); > + ret = 0; > + continue; > + } > + break; > + } > + > + end_offset = ADDRS_PER_PAGE(dn.node_page, inode); > + count = min(end_offset - dn.ofs_in_node, last_idx - page_idx); > + > + ret = release_compress_blocks(&dn, count); > + > + f2fs_put_dnode(&dn); > + > + if (ret < 0) > + break; > + > + page_idx += count; > + released_blocks += ret; > + } > + > + up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]); > + up_write(&F2FS_I(inode)->i_mmap_sem); > + > + inode_unlock(inode); > +out: > + mnt_drop_write_file(filp); > + > + if (!ret) > + ret = put_user(released_blocks, (u64 __user *)arg); > + > + return ret; > +} > + > long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > { > if (unlikely(f2fs_cp_error(F2FS_I_SB(file_inode(filp))))) > @@ -3496,6 +3620,8 @@ long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > return f2fs_set_volume_name(filp, arg); > case F2FS_IOC_GET_COMPRESS_BLOCKS: > return f2fs_get_compress_blocks(filp, arg); > + case F2FS_IOC_RELEASE_COMPRESS_BLOCKS: > + return f2fs_release_compress_blocks(filp, arg); > default: > return -ENOTTY; > } > @@ -3654,6 +3780,7 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) > case F2FS_IOC_GET_VOLUME_NAME: > case F2FS_IOC_SET_VOLUME_NAME: > case F2FS_IOC_GET_COMPRESS_BLOCKS: > + case F2FS_IOC_RELEASE_COMPRESS_BLOCKS: > break; > default: > return -ENOIOCTLCMD; > -- > 2.18.0.rc1