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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 DED85C3F2CF for ; Fri, 28 Feb 2020 08:20:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B3CF8246A3 for ; Fri, 28 Feb 2020 08:20:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726603AbgB1IUY (ORCPT ); Fri, 28 Feb 2020 03:20:24 -0500 Received: from szxga04-in.huawei.com ([45.249.212.190]:11119 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726490AbgB1IUY (ORCPT ); Fri, 28 Feb 2020 03:20:24 -0500 Received: from DGGEMS404-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id 5A3DCFC4D9A94DCBAD55; Fri, 28 Feb 2020 16:20:12 +0800 (CST) Received: from [10.134.22.195] (10.134.22.195) by smtp.huawei.com (10.3.19.204) with Microsoft SMTP Server (TLS) id 14.3.439.0; Fri, 28 Feb 2020 16:20:09 +0800 Subject: Re: [PATCH v2] f2fs: introduce F2FS_IOC_RELEASE_COMPRESS_BLOCKS To: Jaegeuk Kim CC: , , References: <20200227112621.126505-1-yuchao0@huawei.com> <20200227183052.GA55284@google.com> From: Chao Yu Message-ID: <8cb4552e-e6a2-e57b-1baa-40171e53e120@huawei.com> Date: Fri, 28 Feb 2020 16:20:09 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20200227183052.GA55284@google.com> Content-Type: text/plain; charset="windows-1252" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.134.22.195] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020/2/28 2:30, Jaegeuk Kim wrote: > On 02/27, 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. > > Hmm, once we release the blocks, what happens if we remove the immutable > bit back? Oh, if we allow to overwrite on compress file, i_blocks and real physical blocks usage may be inconsistent? So if we need to support above scenario, should we add another ioctl interface to rollback all compress inode status: - add reserved blocks in dnode blocks - increase i_compr_blocks, i_blocks, total_valid_block_count - remove immutable Thanks, > >> >> Signed-off-by: Chao Yu >> --- >> v2: >> - set inode as immutable in ioctl. >> fs/f2fs/f2fs.h | 6 +++ >> fs/f2fs/file.c | 136 ++++++++++++++++++++++++++++++++++++++++++++++++- >> 2 files changed, 141 insertions(+), 1 deletion(-) >> >> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h >> index 23b93a116c73..4a02edc2454b 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 >> @@ -3956,6 +3958,10 @@ 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 37c1147eb244..b8f01ee9d698 100644 >> --- a/fs/f2fs/file.c >> +++ b/fs/f2fs/file.c >> @@ -550,6 +550,7 @@ 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); >> @@ -588,7 +589,9 @@ 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) >> @@ -3403,6 +3406,134 @@ 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); >> + >> + if (!IS_IMMUTABLE(inode)) { >> + F2FS_I(inode)->i_flags |= F2FS_IMMUTABLE_FL; >> + f2fs_set_inode_flags(inode); >> + inode->i_ctime = current_time(inode); >> + f2fs_mark_inode_dirty_sync(inode, true); >> + } >> + >> + 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))))) >> @@ -3483,6 +3614,8 @@ 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; >> } >> @@ -3643,6 +3776,7 @@ 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 > . >