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| -rw-r--r-- | Documentation/filesystems/btrfs.txt | 91 | ||||
| -rw-r--r-- | fs/btrfs/COPYING | 356 | ||||
| -rw-r--r-- | fs/btrfs/INSTALL | 48 |
3 files changed, 91 insertions, 404 deletions
diff --git a/Documentation/filesystems/btrfs.txt b/Documentation/filesystems/btrfs.txt new file mode 100644 index 00000000000..64087c34327 --- /dev/null +++ b/Documentation/filesystems/btrfs.txt @@ -0,0 +1,91 @@ + + BTRFS + ===== + +Btrfs is a new copy on write filesystem for Linux aimed at +implementing advanced features while focusing on fault tolerance, +repair and easy administration. Initially developed by Oracle, Btrfs +is licensed under the GPL and open for contribution from anyone. + +Linux has a wealth of filesystems to choose from, but we are facing a +number of challenges with scaling to the large storage subsystems that +are becoming common in today's data centers. Filesystems need to scale +in their ability to address and manage large storage, and also in +their ability to detect, repair and tolerate errors in the data stored +on disk. Btrfs is under heavy development, and is not suitable for +any uses other than benchmarking and review. The Btrfs disk format is +not yet finalized. + +The main Btrfs features include: + + * Extent based file storage (2^64 max file size) + * Space efficient packing of small files + * Space efficient indexed directories + * Dynamic inode allocation + * Writable snapshots + * Subvolumes (separate internal filesystem roots) + * Object level mirroring and striping + * Checksums on data and metadata (multiple algorithms available) + * Compression + * Integrated multiple device support, with several raid algorithms + * Online filesystem check (not yet implemented) + * Very fast offline filesystem check + * Efficient incremental backup and FS mirroring (not yet implemented) + * Online filesystem defragmentation + + + + MAILING LIST + ============ + +There is a Btrfs mailing list hosted on vger.kernel.org. You can +find details on how to subscribe here: + +http://vger.kernel.org/vger-lists.html#linux-btrfs + +Mailing list archives are available from gmane: + +http://dir.gmane.org/gmane.comp.file-systems.btrfs + + + + IRC + === + +Discussion of Btrfs also occurs on the #btrfs channel of the Freenode +IRC network. + + + + UTILITIES + ========= + +Userspace tools for creating and manipulating Btrfs file systems are +available from the git repository at the following location: + + http://git.kernel.org/?p=linux/kernel/git/mason/btrfs-progs-unstable.git + git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-progs-unstable.git + +These include the following tools: + +mkfs.btrfs: create a filesystem + +btrfsctl: control program to create snapshots and subvolumes: + + mount /dev/sda2 /mnt + btrfsctl -s new_subvol_name /mnt + btrfsctl -s snapshot_of_default /mnt/default + btrfsctl -s snapshot_of_new_subvol /mnt/new_subvol_name + btrfsctl -s snapshot_of_a_snapshot /mnt/snapshot_of_new_subvol + ls /mnt + default snapshot_of_a_snapshot snapshot_of_new_subvol + new_subvol_name snapshot_of_default + + Snapshots and subvolumes cannot be deleted right now, but you can + rm -rf all the files and directories inside them. + +btrfsck: do a limited check of the FS extent trees. + +btrfs-debug-tree: print all of the FS metadata in text form. Example: + + btrfs-debug-tree /dev/sda2 >& big_output_file diff --git a/fs/btrfs/COPYING b/fs/btrfs/COPYING deleted file mode 100644 index ca442d313d8..00000000000 --- a/fs/btrfs/COPYING +++ /dev/null @@ -1,356 +0,0 @@ - - NOTE! This copyright does *not* cover user programs that use kernel - services by normal system calls - this is merely considered normal use - of the kernel, and does *not* fall under the heading of "derived work". - Also note that the GPL below is copyrighted by the Free Software - Foundation, but the instance of code that it refers to (the Linux - kernel) is copyrighted by me and others who actually wrote it. - - Also note that the only valid version of the GPL as far as the kernel - is concerned is _this_ particular version of the license (ie v2, not - v2.2 or v3.x or whatever), unless explicitly otherwise stated. - - Linus Torvalds - ----------------------------------------- - - GNU GENERAL PUBLIC LICENSE - Version 2, June 1991 - - Copyright (C) 1989, 1991 Free Software Foundation, Inc. - 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA - Everyone is permitted to copy and distribute verbatim copies - of this license document, but changing it is not allowed. - - Preamble - - The licenses for most software are designed to take away your -freedom to share and change it. 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If this is what you want to do, use the GNU Library General -Public License instead of this License. diff --git a/fs/btrfs/INSTALL b/fs/btrfs/INSTALL deleted file mode 100644 index 16b45a56878..00000000000 --- a/fs/btrfs/INSTALL +++ /dev/null @@ -1,48 +0,0 @@ -Install Instructions - -Btrfs puts snapshots and subvolumes into the root directory of the FS. This -directory can only be changed by btrfsctl right now, and normal filesystem -operations do not work on it. The default subvolume is called 'default', -and you can create files and directories in mount_point/default - -Btrfs uses libcrc32c in the kernel for file and metadata checksums. You need -to compile the kernel with: - -CONFIG_LIBCRC32C=m - -libcrc32c can be static as well. Once your kernel is setup, typing make in the -btrfs module sources will build against the running kernel. When the build is -complete: - -modprobe libcrc32c -insmod btrfs.ko - -The Btrfs utility programs require libuuid to build. This can be found -in the e2fsprogs sources, and is usually available as libuuid or -e2fsprogs-devel from various distros. - -Building the utilities is just make ; make install. The programs go -into /usr/local/bin. The commands available are: - -mkfs.btrfs: create a filesystem - -btrfsctl: control program to create snapshots and subvolumes: - - mount /dev/sda2 /mnt - btrfsctl -s new_subvol_name /mnt - btrfsctl -s snapshot_of_default /mnt/default - btrfsctl -s snapshot_of_new_subvol /mnt/new_subvol_name - btrfsctl -s snapshot_of_a_snapshot /mnt/snapshot_of_new_subvol - ls /mnt - default snapshot_of_a_snapshot snapshot_of_new_subvol - new_subvol_name snapshot_of_default - - Snapshots and subvolumes cannot be deleted right now, but you can - rm -rf all the files and directories inside them. - -btrfsck: do a limited check of the FS extent trees.</li> - -debug-tree: print all of the FS metadata in text form. Example: - - debug-tree /dev/sda2 >& big_output_file - |