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prefer-encrypt=mutual; keydata= mQENBFnVga8BCACyhFP3ExcTIuB73jDIBA/vSoYcTyysFQzPvez64TUSCv1SgXEByR7fju3o 8RfaWuHCnkkea5luuTZMqfgTXrun2dqNVYDNOV6RIVrc4YuG20yhC1epnV55fJCThqij0MRL 1NxPKXIlEdHvN0Kov3CtWA+R1iNN0RCeVun7rmOrrjBK573aWC5sgP7YsBOLK79H3tmUtz6b 9Imuj0ZyEsa76Xg9PX9Hn2myKj1hfWGS+5og9Va4hrwQC8ipjXik6NKR5GDV+hOZkktU81G5 gkQtGB9jOAYRs86QG/b7PtIlbd3+pppT0gaS+wvwMs8cuNG+Pu6KO1oC4jgdseFLu7NpABEB AAG0IlF1IFdlbnJ1byA8cXV3ZW5ydW8uYnRyZnNAZ214LmNvbT6JAVQEEwEIAD4CGwMFCwkI BwIGFQgJCgsCBBYCAwECHgECF4AWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCWdWCnQUJCWYC bgAKCRDCPZHzoSX+qAR8B/94VAsSNygx1C6dhb1u1Wp1Jr/lfO7QIOK/nf1PF0VpYjTQ2au8 ihf/RApTna31sVjBx3jzlmpy+lDoPdXwbI3Czx1PwDbdhAAjdRbvBmwM6cUWyqD+zjVm4RTG rFTPi3E7828YJ71Vpda2qghOYdnC45xCcjmHh8FwReLzsV2A6FtXsvd87bq6Iw2axOHVUax2 FGSbardMsHrya1dC2jF2R6n0uxaIc1bWGweYsq0LXvLcvjWH+zDgzYCUB0cfb+6Ib/ipSCYp 3i8BevMsTs62MOBmKz7til6Zdz0kkqDdSNOq8LgWGLOwUTqBh71+lqN2XBpTDu1eLZaNbxSI ilaVuQENBFnVga8BCACqU+th4Esy/c8BnvliFAjAfpzhI1wH76FD1MJPmAhA3DnX5JDORcga CbPEwhLj1xlwTgpeT+QfDmGJ5B5BlrrQFZVE1fChEjiJvyiSAO4yQPkrPVYTI7Xj34FnscPj /IrRUUka68MlHxPtFnAHr25VIuOS41lmYKYNwPNLRz9Ik6DmeTG3WJO2BQRNvXA0pXrJH1fN GSsRb+pKEKHKtL1803x71zQxCwLh+zLP1iXHVM5j8gX9zqupigQR/Cel2XPS44zWcDW8r7B0 q1eW4Jrv0x19p4P923voqn+joIAostyNTUjCeSrUdKth9jcdlam9X2DziA/DHDFfS5eq4fEv ABEBAAGJATwEGAEIACYCGwwWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCXZw1rgUJCWpOfwAK CRDCPZHzoSX+qFcEB/95cs8cM1OQdE/GgOfCGxwgckMeWyzOR7bkAWW0lDVp2hpgJuxBW/gy fmtBnUaifnggx3EE3ev8HTysZU9q0h+TJwwJKGv6sUc8qcTGFDtavnnl+r6xDUY7A6GvXEsS oCEEynby72byGeSovfq/4AWGNPBG1L61Exl+gbqfvbECP3ziXnob009+z9I4qXodHSYINfAk ZkA523JGap12LndJeLk3gfWNZfXEWyGnuciRGbqESkhIRav8ootsCIops/SqXm0/k+Kcl4gG UO/iD/T5oagaDh0QtOd8RWSMwLxwn8uIhpH84Q4X1LadJ5NCgGa6xPP5qqRuiC+9gZqbq4Nj Message-ID: Date: Wed, 24 Jun 2020 07:27:46 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.9.0 MIME-Version: 1.0 In-Reply-To: <20200623185032.14983-1-dsterba@suse.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="d8PbfVFu88JR0qoDva0O9TyFLCfgOOMpa" X-Provags-ID: V03:K1:oIoMFt11nCuxxxp0OhTNNHz5Qu3SFJicgYiNV+BIqteKUPA4YTZ m6m6+0vNDGfjc/BWNpi470c+ZI/uGrkzFbdm7gosNI9vWTnFDXQCcglRzxVDxz9HXizQPvS Eog2Tivn5PD2Lfgy1qjpUg9/9usbcx5mleNy5bm2Onw0r0iE5MkoHC60zIc3WPDHoGAxd7S Lw9q+lE88gAR+DnP66ALQ== X-UI-Out-Filterresults: notjunk:1;V03:K0:ZuW1scwwLTo=:VE4d/C+xgTr1PGOBoVVZ64 sDJQe28r99lcPUJcFuFwy2RSA2ea6i/o9ZZG/QPjxFa7gJe+h9dX82id9pvDk3Sk+UEr0e8kZ vCWmThrbyU8xm73xh5auOFvzRi+jyhuJPaCxF7yorjSiYD2LTQ+n9uPSECyuP2psw+0mfhNCs VpzYpz1zBBBGbP3NlifRJy7kx1MB90YtpUwMpY/p2k8tl33dMEVumc069cMAbsbQ6WXzAiyYm pT/k/+8ekd07wEgKccpPJeHK/SwFBu999jpk27buxxg831cHZS5/JaRrCMIr6TGiqR1iWWTyO 1ufCIZCGUkSM1FWcsEoGRtCCHida8OAcWJHEg1h1nAfNXwN9oP6m8Jw6gUc2bauERa3EyzyDP Cf3yIPoh2G+BP8YTBnWPoOerNQu+kSjIvDYxoxg2SpJlkPoEdovg3GydxIuzhx+SfVCmPbWTu gpw0sinsgZH/KyMxeBXM9p8KiqB+YYzY9AZYUvG6orW9URgEinWEENA6flHmfq4Ca0bz+HKFP ky90pqcaB+6ccdPR0HZ92xRV+Mbk0jNreTdo9VgUCEDOq97OlRcfL2vG4gEyyOcngHlW2bEpT 2l24QBQuBz+q9sxpFEIS7i9HTwQPKvCTpl7i8UeWq0G0fqju6KysAWB9y7J94HmCYUPrRTReR rgOMN56N+HDA7peRVsTtzIrJC1tEy/5U6+QFqzJAmXq9Klm4Vzps4Qz4/E3SF6uQ2FTwn/q/J RDAI3QRLs9CHkBqn3SBz41WvSf740XI+7FDNxmgNVgl3NEmzqdhSJs3K/xpkK7Z1jTWG6QgfZ aqwNgVehdUShoMzoODcB2LkvCslvP9NkER34TI1qCifZ+dh6J7hbLjLPLH1A9AA7dnKPxWa+q llUp0T4Blmwk+kjwxqLVNc6IzVz/IlVX6B5xiT8mTelNkM2XMwxhevSOyVECzhpFBGHWxPqYe FM922LIMUiVBBc9jtqNj3KS7rNdICjH12ktYvWIVUHT7C53HZselu9gQPDi40it8Tl3br0RAW g9ol1PBnR2IPLw7L0v8ljRH1OlV7afzd8Tb76po3nszzzJybQGdf9Tdigw0tQ3gcwd81xISuR 6qGscbElFjSlUPyVKpKyQl4TwlbwNGTy9FDd54h1c1oAlRXuFhr88lEUGHnN2Un8bPvhkwn+3 wVS2OSC+T6rESapxiH2t1uFGn01s5VZyh5gd3jknLQdyihKnHYon14wnaJ55+xuNllQvdxuDP t1/03DJSdJwqAteUO Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --d8PbfVFu88JR0qoDva0O9TyFLCfgOOMpa Content-Type: multipart/mixed; boundary="RQFVDtSVn5c1CD98l6xqeEnAqiJN8D0Pu" --RQFVDtSVn5c1CD98l6xqeEnAqiJN8D0Pu Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 2020/6/24 =E4=B8=8A=E5=8D=882:50, David Sterba wrote: > Estimated time of removal of the functionality is 5.11, the option will= > be still parsed but not doing anything. Great that we don't need to test for a mount option that no one really us= es. >=20 > Reasons for deprecation and removal: >=20 > - very poor naming choice of the mount option, it's supposed to cache > and reuse the inode _numbers_, but it sounds a some generic cache for= > inodes >=20 > - the only known usecase where this option would make sense is on a > 32bit architecture where inode numbers in one subvolume would be > exhausted due to 32bit inode::i_ino >=20 > - the cache is stored on disk, consumes space, needs to be loaded and > written back >=20 > - new inode number allocation is slower due to lookups into the cache > (compared to a simple increment which is the default) >=20 > - uses the free-space-cache code that is going to be deprecated as well= > in the future >=20 > Known problems: >=20 > - since 2011, returning EEXIST when there's not enough space in a page > to store all checksums, see commit 4b9465cb9e38 ("Btrfs: add mount -o= > inode_cache") >=20 > Remaining issues: >=20 > - if the option was enabled, new inodes created, the option disabled > again, the cache is still stored on the devices and there's currently= > no way to remove it What about "btrfs rescue remove-deprecated-feature inode_cache"? I really don't want kernel to do the hassle. Thanks, Qu >=20 > Signed-off-by: David Sterba > --- > fs/btrfs/super.c | 2 ++ > 1 file changed, 2 insertions(+) >=20 > diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c > index 98fe2a634c70..3f1abbeef66c 100644 > --- a/fs/btrfs/super.c > +++ b/fs/btrfs/super.c > @@ -827,6 +827,8 @@ int btrfs_parse_options(struct btrfs_fs_info *info,= char *options, > } > break; > case Opt_inode_cache: > + btrfs_warn(info, > + "the 'inode_cache' option is deprecated and will be stop working in 5= =2E11"); > btrfs_set_pending_and_info(info, INODE_MAP_CACHE, > "enabling inode map caching"); > break; >=20 --RQFVDtSVn5c1CD98l6xqeEnAqiJN8D0Pu-- --d8PbfVFu88JR0qoDva0O9TyFLCfgOOMpa Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEELd9y5aWlW6idqkLhwj2R86El/qgFAl7yj/IACgkQwj2R86El /qjZSgf+KRTT1ZPoC6w1EbAoPvGmDntjXEOkEJxtdtMfFeZtPbqFayjtRuHLpkpg YEGmb0/PEkGwNVHeeeFa2D9MsTae60dqL+FVwSEFBFPhXEry3308a+3UQ3/t0KJv w6ZFD5jy+Sl1ShauQqNCmgaHAcAcUzpZTWn43yvAdhRhpJQfBsqVeg04ZGBkpfV+ MO3g689yXiOt5ZukorvCn2a54ZIdU5zyS7VY7lPNE9m/iiA2SqRtyFxwi+kM3szx BpwZGMi0UwN9vO0O2jUlJfBhxtQgmcSfLsP8na01Dzw43tmDtOeDc3Rfz8Cg052H 56gvRKvYSL45p8qbfl/BOiiKvEwxNw== =ysaq -----END PGP SIGNATURE----- --d8PbfVFu88JR0qoDva0O9TyFLCfgOOMpa--