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Message-ID: <dd1ea728-4cb6-e35d-dc76-a1d62bead69a@kernel.org>
Date:   Sun, 22 May 2022 20:43:56 +0800
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Subject: Re: [f2fs-dev] [PATCH v3] f2fs: change the current atomic write way
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To:     Daeho Jeong <daeho43@gmail.com>, linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net, kernel-team@android.com
Cc:     Daeho Jeong <daehojeong@google.com>
References: <20220428181809.2352352-1-daeho43@gmail.com>
From:   Chao Yu <chao@kernel.org>
In-Reply-To: <20220428181809.2352352-1-daeho43@gmail.com>
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On 2022/4/29 2:18, Daeho Jeong wrote:> +		*old_addr = dn.data_blkaddr;
> +		f2fs_truncate_data_blocks_range(&dn, 1);
> +		dec_valid_block_count(sbi, F2FS_I(inode)->cow_inode, count);
> +		inc_valid_block_count(sbi, inode, &count);
> +		f2fs_replace_block(sbi, &dn, dn.data_blkaddr, new_addr,
> +					ni.version, true, false);

My concern is, if cow_inode's data was persisted into previous checkpoint,
and then f2fs_replace_block() will update SSA from cow_inode to inode?
it will cause inconsistent status of last valid checkpoint? Or am I mssing
something?

> -		f2fs_submit_merged_write_cond(sbi, inode, NULL, 0, DATA);
> +			new = f2fs_kmem_cache_alloc(revoke_entry_slab, GFP_NOFS,
> +							true, NULL);
> +			if (!new) {
> +				f2fs_put_dnode(&dn);
> +				ret = -ENOMEM;
> +				goto out;

It doesn't need to handle failure of f2fs_kmem_cache_alloc()
due to nofail parameter is true.

Thanks,