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 9BA9CC76191 for ; Thu, 18 Jul 2019 04:00:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6EA90208C0 for ; Thu, 18 Jul 2019 04:00:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563422408; bh=XHxvAzXMESKUif9uHHTNssIoixW2oCEvuFfuaMJvfk0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=F7YCVsrHcrvhHHuANFVxF+pRkyS/RI4J4VgGi1o7C4ZLBbbnfP7AJMXvC/+EGL1QO 459UXrz7nr3UbhNz/1MREk51GBKBW7KlaiXQ2LysHNw2RhQU/LaMuOTEHj7rja3i/y ZTdX7A1TubNhpQKbpAFVE4oqK/uUEZQsle5QSO8g= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726467AbfGREAH (ORCPT ); Thu, 18 Jul 2019 00:00:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:46888 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725613AbfGREAH (ORCPT ); Thu, 18 Jul 2019 00:00:07 -0400 Received: from localhost (unknown [104.132.1.68]) (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 748FF2085A; Thu, 18 Jul 2019 04:00:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563422406; bh=XHxvAzXMESKUif9uHHTNssIoixW2oCEvuFfuaMJvfk0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=OUR/nfX0mtrLRj8tgV95jebAyyh7jJxswB1enkiX1ZqrDdbuMTCHtvnPsnYRyGv8k 2pIBsuQlN64LIFelNWLBibjALSnahA0kdNaOzJ+2N8tMdrdfrUxST/iFSRGjAQLMyc J77HQTOVyRqOdvgT4R4lwbFRWoIFOJLxraYARLFA= Date: Wed, 17 Jul 2019 21:00:05 -0700 From: Jaegeuk Kim To: Chao Yu Cc: linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Subject: Re: [f2fs-dev] [PATCH v2] f2fs: fix to read source block before invalidating it Message-ID: <20190718040005.GA81995@jaegeuk-macbookpro.roam.corp.google.com> References: <20190718013718.70335-1-jaegeuk@kernel.org> <20190718031214.GA78336@jaegeuk-macbookpro.roam.corp.google.com> <19a25101-da74-de98-6ca4-a9fd9fa09ef2@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <19a25101-da74-de98-6ca4-a9fd9fa09ef2@huawei.com> User-Agent: Mutt/1.8.2 (2017-04-18) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/18, Chao Yu wrote: > On 2019/7/18 11:12, Jaegeuk Kim wrote: > > f2fs_allocate_data_block() invalidates old block address and enable new block > > address. Then, if we try to read old block by f2fs_submit_page_bio(), it will > > give WARN due to reading invalid blocks. > > > > Let's make the order sanely back. > > Hmm.. to avoid WARM, we may suffer one more memcpy, I suspect this can reduce > online resize or foreground gc ioctl performance... I worried about performance tho, more concern came to me that there may exist a chance that other thread can allocate and write something in old block address. > > Can we just relief to use DATA_GENERIC_ENHANCE_READ for this case...? We need to keep consistency for this api. Thanks, > > > > > Signed-off-by: Jaegeuk Kim > > Except performance, I'm okay with this change. > > Reviewed-by: Chao Yu > > Thanks, > > > --- > > v2: > > I was fixing the comments. :) > > > > fs/f2fs/gc.c | 70 +++++++++++++++++++++++++--------------------------- > > 1 file changed, 34 insertions(+), 36 deletions(-) > > > > diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c > > index 6691f526fa40..8974672db78f 100644 > > --- a/fs/f2fs/gc.c > > +++ b/fs/f2fs/gc.c > > @@ -796,6 +796,29 @@ static int move_data_block(struct inode *inode, block_t bidx, > > if (lfs_mode) > > down_write(&fio.sbi->io_order_lock); > > > > + mpage = f2fs_grab_cache_page(META_MAPPING(fio.sbi), > > + fio.old_blkaddr, false); > > + if (!mpage) > > + goto up_out; > > + > > + fio.encrypted_page = mpage; > > + > > + /* read source block in mpage */ > > + if (!PageUptodate(mpage)) { > > + err = f2fs_submit_page_bio(&fio); > > + if (err) { > > + f2fs_put_page(mpage, 1); > > + goto up_out; > > + } > > + lock_page(mpage); > > + if (unlikely(mpage->mapping != META_MAPPING(fio.sbi) || > > + !PageUptodate(mpage))) { > > + err = -EIO; > > + f2fs_put_page(mpage, 1); > > + goto up_out; > > + } > > + } > > + > > f2fs_allocate_data_block(fio.sbi, NULL, fio.old_blkaddr, &newaddr, > > &sum, CURSEG_COLD_DATA, NULL, false); > > > > @@ -803,44 +826,18 @@ static int move_data_block(struct inode *inode, block_t bidx, > > newaddr, FGP_LOCK | FGP_CREAT, GFP_NOFS); > > if (!fio.encrypted_page) { > > err = -ENOMEM; > > - goto recover_block; > > - } > > - > > - mpage = f2fs_pagecache_get_page(META_MAPPING(fio.sbi), > > - fio.old_blkaddr, FGP_LOCK, GFP_NOFS); > > - if (mpage) { > > - bool updated = false; > > - > > - if (PageUptodate(mpage)) { > > - memcpy(page_address(fio.encrypted_page), > > - page_address(mpage), PAGE_SIZE); > > - updated = true; > > - } > > f2fs_put_page(mpage, 1); > > - invalidate_mapping_pages(META_MAPPING(fio.sbi), > > - fio.old_blkaddr, fio.old_blkaddr); > > - if (updated) > > - goto write_page; > > - } > > - > > - err = f2fs_submit_page_bio(&fio); > > - if (err) > > - goto put_page_out; > > - > > - /* write page */ > > - lock_page(fio.encrypted_page); > > - > > - if (unlikely(fio.encrypted_page->mapping != META_MAPPING(fio.sbi))) { > > - err = -EIO; > > - goto put_page_out; > > - } > > - if (unlikely(!PageUptodate(fio.encrypted_page))) { > > - err = -EIO; > > - goto put_page_out; > > + goto recover_block; > > } > > > > -write_page: > > + /* write target block */ > > f2fs_wait_on_page_writeback(fio.encrypted_page, DATA, true, true); > > + memcpy(page_address(fio.encrypted_page), > > + page_address(mpage), PAGE_SIZE); > > + f2fs_put_page(mpage, 1); > > + invalidate_mapping_pages(META_MAPPING(fio.sbi), > > + fio.old_blkaddr, fio.old_blkaddr); > > + > > set_page_dirty(fio.encrypted_page); > > if (clear_page_dirty_for_io(fio.encrypted_page)) > > dec_page_count(fio.sbi, F2FS_DIRTY_META); > > @@ -871,11 +868,12 @@ static int move_data_block(struct inode *inode, block_t bidx, > > put_page_out: > > f2fs_put_page(fio.encrypted_page, 1); > > recover_block: > > - if (lfs_mode) > > - up_write(&fio.sbi->io_order_lock); > > if (err) > > f2fs_do_replace_block(fio.sbi, &sum, newaddr, fio.old_blkaddr, > > true, true); > > +up_out: > > + if (lfs_mode) > > + up_write(&fio.sbi->io_order_lock); > > put_out: > > f2fs_put_dnode(&dn); > > out: > > > > > _______________________________________________ > Linux-f2fs-devel mailing list > Linux-f2fs-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel