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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4B766C07E9D for ; Thu, 29 Sep 2022 07:37:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235280AbiI2Hg6 (ORCPT ); Thu, 29 Sep 2022 03:36:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40058 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230015AbiI2Hgy (ORCPT ); Thu, 29 Sep 2022 03:36:54 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 677FD139416 for ; Thu, 29 Sep 2022 00:36:53 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 2AC26B8237D for ; Thu, 29 Sep 2022 07:36:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8EFECC433D7; Thu, 29 Sep 2022 07:36:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1664437010; bh=zoRODf+0JGREJ0meYcsO7CBJh8QP25i3a9LjaGUnhYk=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=oWANY7OLHl4u9yr6J9BSRdsSomUwxWRgoNG0ZXzFwKg962SHe6WwCUcXKgMUIZQO2 AHjBCQSNQHH78DntN16q784xdFszeXRBzC/fI9icxfZQhytomPSKY4RUEx+qucDR+T bisxlaTpoSxVkDykLc/HC2YsVXP+UoAJJIzdHeE9iZrTg2k7M1i0tbIQyfh9i21Ay+ f4WbZOncXmUOfrOjrAdzkiYVhr8/NAkteOtkHTlu4egyY1o53XypmiKHlIym26l663 ugaKhmSWv2tWlXkTpMJ11wqabyVbWfWmt2Knk5cmVzFPbyLfmlVGVIpY0MbRQIo5OP mryLlDCIy6mEg== Message-ID: Date: Thu, 29 Sep 2022 15:36:45 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.13.0 Subject: Re: [f2fs-dev] [PATCH v2] f2fs: introduce F2FS_IOC_START_ATOMIC_REPLACE Content-Language: en-US To: Daeho Jeong , linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, kernel-team@android.com Cc: Daeho Jeong References: <20220920014036.2295853-1-daeho43@gmail.com> From: Chao Yu In-Reply-To: <20220920014036.2295853-1-daeho43@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022/9/20 9:40, Daeho Jeong wrote: > From: Daeho Jeong > > introduce a new ioctl to replace the whole content of a file atomically, > which means it induces truncate and content update at the same time. > We can start it with F2FS_IOC_START_ATOMIC_REPLACE and complete it with > F2FS_IOC_COMMIT_ATOMIC_WRITE. Or abort it with > F2FS_IOC_ABORT_ATOMIC_WRITE. > > Signed-off-by: Daeho Jeong > --- > v2: add undefined ioctl number reported by > --- > fs/f2fs/data.c | 3 +++ > fs/f2fs/f2fs.h | 1 + > fs/f2fs/file.c | 12 ++++++++++-- > fs/f2fs/segment.c | 14 +++++++++++++- > include/uapi/linux/f2fs.h | 1 + > 5 files changed, 28 insertions(+), 3 deletions(-) > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > index 6cd29a575105..d3d32db3a25d 100644 > --- a/fs/f2fs/data.c > +++ b/fs/f2fs/data.c > @@ -3438,6 +3438,9 @@ static int prepare_atomic_write_begin(struct f2fs_sb_info *sbi, > else if (*blk_addr != NULL_ADDR) > return 0; > > + if (is_inode_flag_set(inode, FI_ATOMIC_REPLACE)) > + goto reserve_block; > + > /* Look for the block in the original inode */ > err = __find_data_block(inode, index, &ori_blk_addr); > if (err) > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > index 539da7f12cfc..2c49da12d6d8 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -764,6 +764,7 @@ enum { > FI_COMPRESS_RELEASED, /* compressed blocks were released */ > FI_ALIGNED_WRITE, /* enable aligned write */ > FI_COW_FILE, /* indicate COW file */ > + FI_ATOMIC_REPLACE, /* indicate atomic replace */ > FI_MAX, /* max flag, never be used */ > }; > > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c > index 4f9b80c41b1e..4abd9d2a55b3 100644 > --- a/fs/f2fs/file.c > +++ b/fs/f2fs/file.c > @@ -1982,7 +1982,7 @@ static int f2fs_ioc_getversion(struct file *filp, unsigned long arg) > return put_user(inode->i_generation, (int __user *)arg); > } > > -static int f2fs_ioc_start_atomic_write(struct file *filp) > +static int f2fs_ioc_start_atomic_write(struct file *filp, bool truncate) > { > struct inode *inode = file_inode(filp); > struct user_namespace *mnt_userns = file_mnt_user_ns(filp); > @@ -2051,6 +2051,12 @@ static int f2fs_ioc_start_atomic_write(struct file *filp) > > isize = i_size_read(inode); > fi->original_i_size = isize; > + if (truncate) { > + set_inode_flag(inode, FI_ATOMIC_REPLACE); > + truncate_inode_pages_final(inode->i_mapping); > + f2fs_i_size_write(inode, 0); > + isize = 0; > + } Hi Daeho, isize should be updated after tagging inode as atomic_write one? otherwise f2fs_mark_inode_dirty_sync() may update isize to inode page, latter checkpoint may persist that change? IIUC... Thanks, > f2fs_i_size_write(fi->cow_inode, isize); > > spin_lock(&sbi->inode_lock[ATOMIC_FILE]); > @@ -4080,7 +4086,9 @@ static long __f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > case FS_IOC_GETVERSION: > return f2fs_ioc_getversion(filp, arg); > case F2FS_IOC_START_ATOMIC_WRITE: > - return f2fs_ioc_start_atomic_write(filp); > + return f2fs_ioc_start_atomic_write(filp, false); > + case F2FS_IOC_START_ATOMIC_REPLACE: > + return f2fs_ioc_start_atomic_write(filp, true); > case F2FS_IOC_COMMIT_ATOMIC_WRITE: > return f2fs_ioc_commit_atomic_write(filp); > case F2FS_IOC_ABORT_ATOMIC_WRITE: > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > index 143b7ea0fb8e..c524538a9013 100644 > --- a/fs/f2fs/segment.c > +++ b/fs/f2fs/segment.c > @@ -263,14 +263,26 @@ static void __complete_revoke_list(struct inode *inode, struct list_head *head, > bool revoke) > { > struct revoke_entry *cur, *tmp; > + pgoff_t start_index = 0; > + bool truncate = is_inode_flag_set(inode, FI_ATOMIC_REPLACE); > > list_for_each_entry_safe(cur, tmp, head, list) { > - if (revoke) > + if (revoke) { > __replace_atomic_write_block(inode, cur->index, > cur->old_addr, NULL, true); > + } else if (truncate) { > + f2fs_truncate_hole(inode, start_index, cur->index); > + start_index = cur->index + 1; > + } > + > list_del(&cur->list); > kmem_cache_free(revoke_entry_slab, cur); > } > + > + if (!revoke && truncate) { > + f2fs_do_truncate_blocks(inode, start_index * PAGE_SIZE, false); > + clear_inode_flag(inode, FI_ATOMIC_REPLACE); > + } > } > > static int __f2fs_commit_atomic_write(struct inode *inode) > diff --git a/include/uapi/linux/f2fs.h b/include/uapi/linux/f2fs.h > index 3121d127d5aa..955d440be104 100644 > --- a/include/uapi/linux/f2fs.h > +++ b/include/uapi/linux/f2fs.h > @@ -42,6 +42,7 @@ > struct f2fs_comp_option) > #define F2FS_IOC_DECOMPRESS_FILE _IO(F2FS_IOCTL_MAGIC, 23) > #define F2FS_IOC_COMPRESS_FILE _IO(F2FS_IOCTL_MAGIC, 24) > +#define F2FS_IOC_START_ATOMIC_REPLACE _IO(F2FS_IOCTL_MAGIC, 25) > > /* > * should be same as XFS_IOC_GOINGDOWN.