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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, 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 4DC2CC433FF for ; Fri, 2 Aug 2019 07:54:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1B9E220449 for ; Fri, 2 Aug 2019 07:54:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389577AbfHBHyI (ORCPT ); Fri, 2 Aug 2019 03:54:08 -0400 Received: from szxga06-in.huawei.com ([45.249.212.32]:49406 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728272AbfHBHyI (ORCPT ); Fri, 2 Aug 2019 03:54:08 -0400 Received: from DGGEMS408-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id F03FD61C8903D48421A4; Fri, 2 Aug 2019 15:54:05 +0800 (CST) Received: from [10.134.22.195] (10.134.22.195) by smtp.huawei.com (10.3.19.208) with Microsoft SMTP Server (TLS) id 14.3.439.0; Fri, 2 Aug 2019 15:54:02 +0800 Subject: Re: [PATCH v3 RESEND] f2fs: introduce sb.required_features to store incompatible features To: Jaegeuk Kim CC: Chao Yu , , References: <20190729150351.12223-1-chao@kernel.org> <20190730231850.GA7097@jaegeuk-macbookpro.roam.corp.google.com> <20190801042215.GC84433@jaegeuk-macbookpro.roam.corp.google.com> <345c55ea-01c2-a9d1-4367-716dbd08ae9d@huawei.com> <20190801223509.GB27597@jaegeuk-macbookpro.roam.corp.google.com> From: Chao Yu Message-ID: <8e906ddb-81d8-b63e-0c19-1ee9fc7f5cbf@huawei.com> Date: Fri, 2 Aug 2019 15:54:00 +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: <20190801223509.GB27597@jaegeuk-macbookpro.roam.corp.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 2019/8/2 6:35, Jaegeuk Kim wrote: > On 08/01, Chao Yu wrote: >> On 2019/8/1 12:22, Jaegeuk Kim wrote: >>> On 07/31, Chao Yu wrote: >>>> On 2019/7/31 7:18, Jaegeuk Kim wrote: >>>>> On 07/29, Chao Yu wrote: >>>>>> From: Chao Yu >>>>>> >>>>>> Later after this patch was merged, all new incompatible feature's >>>>>> bit should be added into sb.required_features field, and define new >>>>>> feature function with F2FS_INCOMPAT_FEATURE_FUNCS() macro. >>>>>> >>>>>> Then during mount, we will do sanity check with enabled features in >>>>>> image, if there are features in sb.required_features that kernel can >>>>>> not recognize, just fail the mount. >>>>>> >>>>>> Signed-off-by: Chao Yu >>>>>> --- >>>>>> v3: >>>>>> - change commit title. >>>>>> - fix wrong macro name. >>>>>> fs/f2fs/f2fs.h | 15 +++++++++++++++ >>>>>> fs/f2fs/super.c | 10 ++++++++++ >>>>>> include/linux/f2fs_fs.h | 3 ++- >>>>>> 3 files changed, 27 insertions(+), 1 deletion(-) >>>>>> >>>>>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h >>>>>> index a6eb828af57f..b8e17d4ddb8d 100644 >>>>>> --- a/fs/f2fs/f2fs.h >>>>>> +++ b/fs/f2fs/f2fs.h >>>>>> @@ -163,6 +163,15 @@ struct f2fs_mount_info { >>>>>> #define F2FS_CLEAR_FEATURE(sbi, mask) \ >>>>>> (sbi->raw_super->feature &= ~cpu_to_le32(mask)) >>>>>> >>>>>> +#define F2FS_INCOMPAT_FEATURES 0 >>>>>> + >>>>>> +#define F2FS_HAS_INCOMPAT_FEATURE(sbi, mask) \ >>>>>> + ((sbi->raw_super->required_features & cpu_to_le32(mask)) != 0) >>>>>> +#define F2FS_SET_INCOMPAT_FEATURE(sbi, mask) \ >>>>>> + (sbi->raw_super->required_features |= cpu_to_le32(mask)) >>>>>> +#define F2FS_CLEAR_INCOMPAT_FEATURE(sbi, mask) \ >>>>>> + (sbi->raw_super->required_features &= ~cpu_to_le32(mask)) >>>>>> + >>>>>> /* >>>>>> * Default values for user and/or group using reserved blocks >>>>>> */ >>>>>> @@ -3585,6 +3594,12 @@ F2FS_FEATURE_FUNCS(lost_found, LOST_FOUND); >>>>>> F2FS_FEATURE_FUNCS(sb_chksum, SB_CHKSUM); >>>>>> F2FS_FEATURE_FUNCS(casefold, CASEFOLD); >>>>>> >>>>>> +#define F2FS_INCOMPAT_FEATURE_FUNCS(name, flagname) \ >>>>>> +static inline int f2fs_sb_has_##name(struct f2fs_sb_info *sbi) \ >>>>>> +{ \ >>>>>> + return F2FS_HAS_INCOMPAT_FEATURE(sbi, F2FS_FEATURE_##flagname); \ >>>>>> +} >>>>>> + >>>>>> #ifdef CONFIG_BLK_DEV_ZONED >>>>>> static inline bool f2fs_blkz_is_seq(struct f2fs_sb_info *sbi, int devi, >>>>>> block_t blkaddr) >>>>>> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c >>>>>> index 5540fee0fe3f..3701dcce90e6 100644 >>>>>> --- a/fs/f2fs/super.c >>>>>> +++ b/fs/f2fs/super.c >>>>>> @@ -2513,6 +2513,16 @@ static int sanity_check_raw_super(struct f2fs_sb_info *sbi, >>>>>> return -EINVAL; >>>>>> } >>>>>> >>>>>> + /* check whether current kernel supports all features on image */ >>>>>> + if (le32_to_cpu(raw_super->required_features) & >>>>> >>>>> ... >>>>> #define F2FS_FEATURE_VERITY 0x0400 /* reserved */ >>>>> ... >>>>> #define F2FS_FEATURE_CASEFOLD 0x1000 >>>>> #define F2FS_FEATURE_SUPPORT 0x1BFF >>>>> >>>>> if (le32_to_cpu(raw_super->required_features) & ~F2FS_FEATURE_SUPPORT) { >>>>> ... >>>>> return -EINVAL; >>>>> } >>>> >>>> Um, I thought .required_features are used to store new feature flags from 0x0. >>>> >>>> All 'F2FS_FEATURE_SUPPORT' bits should be stored in sb.feature instead of >>>> sb.required_features, I'm confused... >>> >>> I'm thinking, >>> >>> f2fs-tools sb->required_features f2fs F2FS_FEATURE_SUPPORT >>> v0 0 v0 no_check -> ok >>> v1 0x1BFF v0 no_check -> ok >>> v0 0 v1 0x1BFF -> ok >>> v1 0x1BFF v1 0x1BFF -> ok >>> v2 0x3BFF v1 0x1BFF -> fail >>> v1 0x1BFF v2 0x3BFF -> ok >>> v2 0x3BFF v2 0x3BFF -> ok >> >> I see, it's a bit waste for 0x1FFF low bits in sb->required_features. Why not >> leaving 0x0FFF in sb->feature w/o sanity check. And make all new incompatible >> features (including casefold) adding into sb->required_features. > > I don't think we can define like this, and we still have 32bits feature filed. > This would give another confusion to understand. VERITY is reserved only now. > > #define F2FS_FEATURE_CASEFOLD 0x0001 Oops, so you want to make .required_features being almost a mirror of .feature, and do sanity check on it... I can see now. :P If so, why not just use .feature: kernel tool v5.2 .. 1.12 #define F2FS_FEATURE_SUPPORT 0x0BFF v5.3 .. 1.13 #define F2FS_FEATURE_CASEFOLD 0x1000 #define F2FS_FEATURE_SUPPORT 0x1BFF v5.4 .. 1.14 #define F2FS_FEATURE_CASEFOLD 0x1000 #define F2FS_FEATURE_COMPRESS 0x2000 #define F2FS_FEATURE_SUPPORT 0x3BFF f2fs-tools sb->feature f2fs F2FS_FEATURE_SUPPORT [enable all features in tools] v1.12 0x0BFF v5.2 no_check -> ok v1.12 0x0BFF v5.3 0x1BFF -> ok v1.12 0x0BFF v5.4 0x3BFF -> ok v1.13 0x1BFF v5.2 that's issue we need to fix v1.13 0x1BFF v5.3 0x1BFF -> ok v1.13 0x1BFF v5.4 0x3BFF -> ok v1.14 0x3BFF v5.2 that's issue we need to fix v1.14 0x3BFF v5.3 0x1BFF -> fail v1.14 0x3BFF v5.4 0x3BFF -> ok Or am I missing something? Thanks, > >> >> Then that would be: >> >> kernel tool >> v5.2 .. 1.12 >> #define F2FS_FEATURE_SUPPORT 0x0000 >> >> v5.3 .. 1.13 >> #define F2FS_FEATURE_CASEFOLD 0x0001 >> #define F2FS_FEATURE_SUPPORT 0x0001 >> >> v5.4 .. 1.14 >> #define F2FS_FEATURE_CASEFOLD 0x0001 >> #define F2FS_FEATURE_COMPRESS 0x0002 >> #define F2FS_FEATURE_SUPPORT 0x0003 >> >> f2fs-tools sb->required_features f2fs F2FS_FEATURE_SUPPORT >> >> v1.12 0x0000 v5.2 no_check -> ok >> v1.12 0x0000 v5.3 0x0001 -> ok >> v1.12 0x0000 v5.4 0x0003 -> ok >> >> v1.13 0x0001 v5.2 that's issue we need to fix >> v1.13 0x0001 v5.3 0x0001 -> ok >> v1.13 0x0001 v5.4 0x0003 -> ok >> >> v1.14 0x0003 v5.2 that's issue we need to fix >> v1.14 0x0003 v5.3 0x0001 -> fail >> v1.14 0x0003 v5.4 0x0003 -> ok >> >> And all compatible features can be added into sb->feature[_VERITY, ....]. >> >> Would that okay to you? >> >> Thanks, >> >>> >>>> >>>> Thanks, >>>> >>>>> >>>>> >>>>>> + ~F2FS_INCOMPAT_FEATURES) { >>>>>> + f2fs_info(sbi, "Unsupported feature: %x: supported: %x", >>>>>> + le32_to_cpu(raw_super->required_features) ^ >>>>>> + F2FS_INCOMPAT_FEATURES, >>>>>> + F2FS_INCOMPAT_FEATURES); >>>>>> + return -EINVAL; >>>>>> + } >>>>>> + >>>>>> /* Check checksum_offset and crc in superblock */ >>>>>> if (__F2FS_HAS_FEATURE(raw_super, F2FS_FEATURE_SB_CHKSUM)) { >>>>>> crc_offset = le32_to_cpu(raw_super->checksum_offset); >>>>>> diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h >>>>>> index a2b36b2e286f..4141be3f219c 100644 >>>>>> --- a/include/linux/f2fs_fs.h >>>>>> +++ b/include/linux/f2fs_fs.h >>>>>> @@ -117,7 +117,8 @@ struct f2fs_super_block { >>>>>> __u8 hot_ext_count; /* # of hot file extension */ >>>>>> __le16 s_encoding; /* Filename charset encoding */ >>>>>> __le16 s_encoding_flags; /* Filename charset encoding flags */ >>>>>> - __u8 reserved[306]; /* valid reserved region */ >>>>>> + __le32 required_features; /* incompatible features to old kernel */ >>>>>> + __u8 reserved[302]; /* valid reserved region */ >>>>>> __le32 crc; /* checksum of superblock */ >>>>>> } __packed; >>>>>> >>>>>> -- >>>>>> 2.22.0 >>>>> . >>>>> >>> . >>> > . >