* fix BTRFS capitalization
* fix repetition
* wording and punctuation in 'Nested subvolumes'
* wording and punctuation in 'system root layouts'
* wording and punctuation in 'Mount options'
* wording in 'Inode numbers'
* wording and punctuation in 'Performance'
- Explain that scrub is device based
- Add extra warning on NOCOW files
Which implies NODATASUM, and can cause unexpected stale data to be
returned.
- Explain the limitation of scrub
As it can only do very basic checksum verification and very basic
mirror based repair.
Signed-off-by: Colin Snover <csnover@users.noreply.github.com>
[ Add an SoB line and commit message, remove the mention of btrfs-check errors,
as there is no evidence/example where btrfs-check failed to choose a good mirror. ]
Signed-off-by: Qu Wenruo <wqu@suse.com>
Since balance is copying the old good data/metadata into a new chunk
(which can be on the same failed device), it's not a safe way to handle
failed devices.
Signed-off-by: Colin Snover <csnover@users.noreply.github.com>
[ Add an SoB and simple commit message, remove the unnecessary
explanation, and guide the user to use `btrfs dev replace` ]
Signed-off-by: Qu Wenruo <wqu@suse.com>
- Btrfs-check does device assembly automatically
Thus no difference when specifying different devices of the same
filesystem
- Btrfs-check automatically choose good metadata
Thus as long as there is any good mirror for metadata, it will not
report error for that repariable metadata.
Signed-off-by: Colin Snover <csnover@users.noreply.github.com>
[ Add an SoB line, remove the scrub recommendation as btrfs-check is
supposed to choose the good mirror ]
Signed-off-by: Qu Wenruo <wqu@suse.com>
- Fix the format of the transid mismatch reason and type
- Fix a typo in the reason
- Explain more on the recoverable case
That both a regular metadata read and read-write scrub can do the
same trick.
- Add an extra data salvage method using "rescue=all,ro" mount option
Signed-off-by: Colin Snover <csnover@users.noreply.github.com>
[ Add an SoB line ]
Signed-off-by: Qu Wenruo <wqu@suse.com>
- The IRC channel
- The mailling list
- The btrfs-progs repo for user space bugs
Signed-off-by: Colin Snover <csnover@users.noreply.github.com>
[ Add an SoB line ]
Signed-off-by: Qu Wenruo <wqu@suse.com>
Added DEV_ITEM object id to the reserved object id list. It's historical reason
to let both of DEV_ITEM and ROOT_TREE have same object id. Developers should
be aware of it.
Signed-off-by: HAN Yuwei <hrx@bupt.moe>
[ Replace immediate number with key names ]
Signed-off-by: Qu Wenruo <wqu@suse.com>
This "stil" -> "still" typo is causing the latest CI spellchecks to fail.
Fix that so we can get a good CI run.
Signed-off-by: Qu Wenruo <wqu@suse.com>
The slides for the talk "Kernel maintainership: an oral tradition",
linked to in the documentation, seem to have gone from the Linux
Foundation website. Change to the version on bootlin.com.
Signed-off-by: Mark Harmstone <maharmstone@fb.com>
Change mkfs.btrfs --subvol so that instead of being of the form --subvol
DIR:FLAGS, it's instead --subvol MODIFIER:DIR, with MODIFIER being ro,
rw, default, or ro-default.
Signed-off-by: Mark Harmstone <maharmstone@fb.com>
The new hard link detection and creation support is done by maintaining
an rb tree with the following members:
- st_ino, st_dev
This is to record the stat() report from the host fs.
With this two, we can detect if it's really a hard link (st_dev
determines one filesystem/subvolume, and st_ino determines the inode
number inside the fs).
- root
This is btrfs root pointer. This a special requirement for the recent
introduced "--subvol" option.
As we can have the following corner case:
rootdir/
|- foobar_hardlink1
|- foobar_hardlink2
|- subv/ <- To be a subvolume inside btrfs
|- foobar_hardlink3
In above case, on the host fs, `subv/` directory is just a regular
directory, but in the new btrfs it will be a subvolume.
In that case, `foobar_hardlink3` cannot be created as a hard link,
but a new inode.
- st_nlink and found_nlink
Records the original reported number of links, and the nlinks we
created inside btrfs.
This is recorded in case we created all hard links and can remove
the entry early.
- btrfs_ino
This is the inode number inside btrfs.
And since we can handle hard links safely, remove all the related
warnings, and add a new note for `--subvol` option, warning about the
case where we need to split hard links due to subvolume boundary.
Pull-request: #873
Signed-off-by: Qu Wenruo <wqu@suse.com>
Change --subvol that it can accept flags, and add a "default" flag that
allows you to mark a subvolume as the default.
Signed-off-by: Mark Harmstone <maharmstone@fb.com>
Add a new option --subvol, which tells mkfs.btrfs to create the
specified directories as subvolumes when used with --rootdir.
Given a populated directory dir, the command
$ mkfs.btrfs --rootdir dir --subvol usr --subvol home --subvol home/username img
will create subvolumes 'usr' and 'home' within the toplevel subvolume,
and subvolume 'username' within the 'home' subvolume. It will fail if
any of the directories do not yet exist.
Pull-request: #868
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Mark Harmstone <maharmstone@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add new option --recursive 'btrfs subvol delete', causing it to pass the
BTRFS_UTIL_DELETE_SUBVOLUME_RECURSIVE flag through to libbtrfsutil.
This can work in two modes, depending on the user:
- regular user - this will skip subvolumes that are not accessible
- root (CAP_SYS_ADMIN) - no limitations
Pull-request: #861
Signed-off-by: Mark Harmstone <maharmstone@meta.com>
Co-authored-by: Omar Sandoval <osandov@osandov.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
[ Add details to man page, fix indent in the doc. ]
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Explain the difference, in case somebody want's to use it as a source to
correct that on Wikipedia.
[ ci skip ]
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs-ioctl.rst was laid out like it should be a man page, including
having a section number, but it wasn't getting installed because there
was not enough content.
Pull-request: #892
Signed-off-by: Mark Harmstone <maharmstone@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Added 0x prefix to HEX numbers and transform some tables to new format.
Pull-request: #881
Signed-off-by: Yuwei Han <hrx@bupt.moe>
[ Fix RST grammar errors ]
Signed-off-by: Qu Wenruo <wqu@suse.com>
The way the CRC32C checksum used for btrfs-send differs from the way
it's used elsewhere in btrfs. Without making the distinction, it's easy
to make the flawed assumption that CRC32C always refers to the same, and
end up with code that produces the wrong checksums.
This small note should guide the reader to the right function.
The best notes on the protocol I found are here:
https://archive.kernel.org/oldwiki/btrfs.wiki.kernel.org/index.php/Design_notes_on_Send/Receive.html
The crc32c might be used in two meanings and this could be confusing
when implementing the send stream protocol.
Rust code describing the algorithm for the crc crate that worked for me:
pub const CRC_32_BTRFS_SEND: crc::Algorithm<u32> = crc::Algorithm {
width: 32, poly: 0x1edc6f41, init: 0, refin: true, refout: true,
xorout: 0, check: 0xe3069283, residue: 0xb798b438
};
(it's a slight variation on the one used in ISCSI)
Note: Documentation/dev/dev-send-stream.rst briefly mentions that
Pull-request: #794
Author: rhn <gihu.rhn@porcupinefactory.org>
[ rephrase changelog and copy text from pull request and add link to
developer documentation of the send stream ]
Signed-off-by: David Sterba <dsterba@suse.com>
Make it more visible what the result of snapshotted subvolume is. This
partially duplicates the other section.
[ci skip]
Issue: #644
Signed-off-by: David Sterba <dsterba@suse.com>
It is possible to create swapfile on a multi-device filesystem but it's
not reliable. The check that verifies that in kernel:
10698 } else if (device != map->stripes[0].dev) {
10699 btrfs_warn(fs_info, "swapfile must be on one device");
10700 ret = -EINVAL;
10701 goto out;
10702 }
This does not count devices but rather the actual placement of the
swapfile extents, so multi-device filesystem with single profile can
create it as long as there's enough space and the allocator decides to
place it properly.
[ci skip]
Pull-request: #839
Signed-off-by: David Sterba <dsterba@suse.com>
The filename sanitization is not recommended as it introduces mismatches
between DIR_ITEM and INODE_REF.
Even hash collision mode (double "-s" option) is not ensured to always
find a hash collision, and when fails to find one, a mismatch happens.
And when a mismatch happens, the kernel will not resolve the path
correctly since kernel uses the hash from DIR_ITEM to lookup the child
inode.
So add a warning into the "-s" option of btrfs-image.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Filenames can contain a newline (or other funny characters), this makes
the dump-tree output confusing, same for xattr names or values that can
binary data. Encode the special characters in the C-style ('\e' ->
"\e", or \NNN if there's no single letter representation). This is based
on the isprint() as it's espected either on a terminal or in a dump
file.
Issue: #350
Issue: #407
Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba
(@silopolis)
Jérémie Tarot
Colin Snover
Colin Snover
HAN Yuwei
Qu Wenruo
Mark Harmstone
Omar Sandoval
Han Yuwei
rhn
Yaroslav Halchenko