From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrey Kuzmin Subject: Re: [PATCH] Snapshot/subvolume listing feature Date: Mon, 16 Nov 2009 16:00:15 +0300 Message-ID: <2a31deca0911160500j6b2b17c3v8b3a3bebd000457d@mail.gmail.com> References: <4B00ADE8.4090205@jp.fujitsu.com> <3d0408630911160015t79044d72u3489a42d57c6f844@mail.gmail.com> <4B011435.2080005@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Cc: yanzheng@21cn.com, linux-btrfs@vger.kernel.org, chris.mason@oracle.com To: TARUISI Hiroaki Return-path: In-Reply-To: <4B011435.2080005@jp.fujitsu.com> List-ID: Just for clarity, getdents is exactly the other interface options discussed couple of weeks back (use virtual directories & standard file-system API). Regards, Andrey On Mon, Nov 16, 2009 at 11:58 AM, TARUISI Hiroaki wrote: > Thank you for your advice. > > I'm aware of redundant search, but I didn't think of > getdents like interface. > > I'll remake it without redundant search. > > Regards, > taruisi > > Yan, Zheng wrote: >> 2009/11/16 TARUISI Hiroaki : >>> I made Snapshot/subvolume listing feature. >>> >>> This feature consists of two patches, for kernel(ioctl), >>> and for progs(btrfsctl). I send these two patches as response >>> of this mail soon. >>> >>> New option '-l' is introduced to btrfsctl for listing. >>> >>> If this option is specified, btrfsctl call new ioctl. New ioctl >>> searches root tree and enumerates subtrees. For each subtrees, >>> ioctl searches directory path to tree root, and enumerates >>> more descendant until no more subtree is found. >>> >>> MANPAGE-like option description and examples are as follows. >>> >>> =A0OPTIONS >>> =A0 =A0 =A0 =A0-l _file_ >>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0List all snapshot/subvolume director= ies under a tree >>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0which _file_ belongs to. >>> >>> =A0EXAMPLES >>> =A0 =A0 =A0 =A0# btrfsctl -l /work/btrfs >>> =A0 =A0Base path =3D /work/btrfs/ >>> =A0 =A0No. =A0 =A0Tree ID =A0 =A0 =A0Subvolume Relative Path >>> =A0 =A0 1 =A0 =A0 =A0 =A0 256 =A0 =A0 =A0ss1/ >>> =A0 =A0 2 =A0 =A0 =A0 =A0 257 =A0 =A0 =A0ss2/ >>> =A0 =A0 3 =A0 =A0 =A0 =A0 258 =A0 =A0 =A0svs1/ss1/ >>> =A0 =A0 4 =A0 =A0 =A0 =A0 259 =A0 =A0 =A0svs1/ss2/ >>> =A0 =A0 5 =A0 =A0 =A0 =A0 260 =A0 =A0 =A0svs2/ss1/ >>> =A0 =A0 6 =A0 =A0 =A0 =A0 261 =A0 =A0 =A0svs2/ss2/ >>> =A0 =A0 7 =A0 =A0 =A0 =A0 262 =A0 =A0 =A0ss3/ >>> =A0 =A0 8 =A0 =A0 =A0 =A0 263 =A0 =A0 =A0ss4/ >>> =A0 =A0 9 =A0 =A0 =A0 =A0 264 =A0 =A0 =A0sv_pool/ >>> =A0 =A010 =A0 =A0 =A0 =A0 265 =A0 =A0 =A0sv_pool/ss01/ >>> =A0 =A011 =A0 =A0 =A0 =A0 266 =A0 =A0 =A0sv_pool/ss02/ >>> =A0 =A012 =A0 =A0 =A0 =A0 267 =A0 =A0 =A0sv_pool/ss03/ >>> =A0 =A013 =A0 =A0 =A0 =A0 268 =A0 =A0 =A0sv_pool/ss04/ >>> =A0 =A014 =A0 =A0 =A0 =A0 269 =A0 =A0 =A0sv_pool/ss05/ >>> =A0 =A015 =A0 =A0 =A0 =A0 270 =A0 =A0 =A0sv_pool/ss06/ >>> =A0 =A016 =A0 =A0 =A0 =A0 271 =A0 =A0 =A0sv_pool/ss07/ >>> =A0 =A017 =A0 =A0 =A0 =A0 272 =A0 =A0 =A0sv_pool/ss08/ >>> =A0 =A018 =A0 =A0 =A0 =A0 273 =A0 =A0 =A0sv_pool/ss09/ >>> =A0 =A019 =A0 =A0 =A0 =A0 274 =A0 =A0 =A0sv_pool/ss10/ >>> =A0operation complete >>> =A0Btrfs v0.19-9-gd67dad2 >>> >> >> Thank you for doing this. >> >> I have a quick look at the patches. It seems the ioctl returns full = path >> to each subvolume and uses sequence ID to indicate the progress >> of listing. Every time the ioctl is called, it tries building full l= ist of >> subvolume, then skip entries that already returned. =A0I think the A= PI is >> suboptimal, a getdents like API is better. (The ioctl only lists sub= volumes >> within a given subvolume, the user program call the ioctl recursivel= y >> to list all subvolumes.) >> >> Yan, Zheng >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-btrf= s" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at =A0http://vger.kernel.org/majordomo-info.html > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs= " in > the body of a message to majordomo@vger.kernel.org > More majordomo info at =A0http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" = in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html