Commit Graph

35 Commits

Author SHA1 Message Date
Nikolay Borisov 451db51bdb btrfs-progs: remove support for BTRFS_SUBVOL_CREATE_ASYNC
Kernel has removed support for this feature in 5.7 so let's remove
support from progs as well.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-06 16:49:21 +02:00
Omar Sandoval e9c2942f38 libbtrfsutil: fix race between subvolume iterator and deletion
Subvolume iteration has a window between when we get a root ref (with
BTRFS_IOC_TREE_SEARCH or BTRFS_IOC_GET_SUBVOL_ROOTREF) and when we look
up the path of the parent directory (with BTRFS_IOC_INO_LOOKUP{,_USER}).
If the subvolume is moved or deleted and its old parent directory is
deleted during that window, then BTRFS_IOC_INO_LOOKUP{,_USER} will fail
with ENOENT. The iteration will then fail with ENOENT as well.

We originally encountered this bug with an application that called
`btrfs subvolume show` (which iterates subvolumes to find snapshots) in
parallel with other threads creating and deleting subvolumes. It can be
reproduced almost instantly with the included test cases.

Subvolume iteration should be robust against concurrent modifications to
subvolumes. So, if a subvolume's parent directory no longer exists, just
skip the subvolume, as it must have been deleted or moved elsewhere.

Reviewed-by: Neal Gompa <ngompa13@gmail.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-07-29 13:01:55 +02:00
David Sterba b3e6260e8a libbtrfsutil: fix test case class name for python bindings
In file test_filesystem.py the class name should be TestFilesystem, this
looks like a typo and does not affect functionality.

Signed-off-by: David Sterba <dsterba@suse.com>
2021-05-06 16:41:47 +02:00
David Sterba 4b6f420aa5 libbtrfsutil: add warning about autogenerated constants.c
Signed-off-by: David Sterba <dsterba@suse.com>
2021-05-06 16:41:47 +02:00
Neal Gompa 9e30f779e3 libbtrfsutil: relicense to LGPLv2.1+
This relicenses the libbtrfsutil library to LGPLv2.1+ from LGPLv3.
People that have contributed non-trivial changes acknowledged the change
and are listed below.

There's a potential licensing conflict with the 'btrfs' utility that is
GPLv2 and statically links libbtrfsutil, this is not a valid combination
per the compatibility matrix as found in
https://www.gnu.org/licenses/gpl-faq.html#AllCompatibility or
http://gplv3.fsf.org/dd3-faq .

We also have an explicit request to change the license [1] (issue #323)
from LGPLv3 to allow use in environments that don't like GPLv3. Though
the library license is not GPLv3, the full text of the license is in the
repository and the 'lesser' part is an addendum. This was perhaps a bit
confusing, nevertheless this gets clarified as well.

[1] https://lore.kernel.org/linux-btrfs/b927ca28-e280-4d79-184f-b72867dbdaa8@denx.de/

Acked-by: Omar Sandoval <osandov@fb.com>
Acked-by: Misono Tomhiro <misono.tomohiro@jp.fujitsu.com>
Acked-by: Qu Wenruo <wqu@suse.com>
Acked-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Acked-by: Anand Jain <anand.jain@oracle.com>
Acked-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Link: https://bugs.debian.org/985400
Issue: #323
Signed-off-by: Neal Gompa <ngompa@fedoraproject.org>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 18:58:26 +02:00
David Sterba a178b6e508 libbtrfsutil: let python-btrfsutil version follow main package version
Neal points out that the python bindings of libbtrfsutil version is set
from the library ABI rather than the package itself. As this brings some
confusion to packaging, derive the verion the main package too.

Link: http://lore.kernel.org/linux-btrfs/CAEg-Je-VLz9zZOKEVa+x0V+dpyojtRcjBw7maO73zpmowdOyTQ@mail.gmail.com
Reported-by: Neal Gompa <ngompa13@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-10-22 20:34:01 +02:00
Qu Wenruo f01d2b8558 libbtrfsutil: Convert to designated initialization for SubvolumeIterator_type
[BUG]
When compiling btrfs-progs with libbtrfsutil on a python3.8 system, we
got the following warning:

  subvolume.c:636:2: warning: initialization of ‘long int’ from ‘void *’ makes integer from pointer without a cast [-Wint-conversion]
    636 |  NULL,     /* tp_print */
        |  ^~~~
  subvolume.c:636:2: note: (near initialization for ‘SubvolumeIterator_type.tp_vectorcall_offset’)

[CAUSE]
C definition of PyTypeObject changed in python 3.8.
Now at the old tp_print, we have tp_vectorcall_offset.

So we got above warning.

[FIX]
C has designated initialization, which can assign values to each named
member, without hard coding to match the offset.
And all the other uninitialized values will be set to 0, so we can save
a lot of unneeded "= 0" or "= NULL" lines.

Just use that awesome feature to avoid any future breakage.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-22 19:09:51 +01:00
Qu Wenruo 425c950cc6 libbtrfsutil: Convert to designated initialization for QgroupInherit_type
[BUG]
When compiling btrfs-progs with libbtrfsutil on a python3.8 system, we
got the following warning:

  qgroup.c:110:2: warning: initialization of ‘long int’ from ‘void *’ makes integer from pointer without a cast [-Wint-conversion]
    110 |  NULL,     /* tp_print */
        |  ^~~~
  qgroup.c:110:2: note: (near initialization for ‘QgroupInherit_type.tp_vectorcall_offset’)

[CAUSE]
C definition of PyTypeObject changed in python 3.8.
Now at the old tp_print, we have tp_vectorcall_offset.

So we got above warning.

[FIX]
C has designated initialization, which can assign values to each named
member, without hard coding to match the offset.
And all the other uninitialized values will be set to 0, so we can save
a lot of unneeded "= 0" or "= NULL" lines.

Just use that awesome feature to avoid any future breakage.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-22 19:09:51 +01:00
Qu Wenruo a528cbeead libbtrfsutil: Convert to designated initialization for BtrfsUtilError_type
[BUG]
When compiling btrfs-progs with libbtrfsutil on a python3.8 system, we
got the following warning:

  error.c:169:2: warning: initialization of ‘long int’ from ‘void *’ makes integer from pointer without a cast [-Wint-conversion]
    169 |  NULL,      /* tp_print */
        |  ^~~~
  error.c:169:2: note: (near initialization for ‘BtrfsUtilError_type.tp_vectorcall_offset’)

[CAUSE]
C definition of PyTypeObject changed in python 3.8.
Now at the old tp_print, we have tp_vectorcall_offset.

So we got above warning.

[FIX]
C has designated initialization, which can assign values to each named
member, without hard coding to match the offset.
Also, uninitialized values will be 0, so we can also save a lot of
unneeded "= 0" or "= NULL" lines.

Just use that awesome feature to avoid any future breakage.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-22 19:09:51 +01:00
Omar Sandoval cba6bae15d libbtrfsutil: don't close fd on error in btrfs_util_subvolume_id_fd()
The caller owns the fd passed to btrfs_util_subvolume_id_fd(), so we
shouldn't close it on error. Fix it, add a regression test, and bump the
library patch version.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-04-26 18:23:27 +02:00
Omar Sandoval 41e19f703d libbtrfsutil: fix unprivileged tests if kernel lacks support
I apparently didn't test this on a pre-4.18 kernel.
test_subvolume_info_unprivileged() checks for an ENOTTY, but this
doesn't seem to work correctly with subTest().
test_subvolume_iterator_unprivileged() doesn't have a check at all. Add
an explicit check to both before doing the actual test.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-01-15 16:20:09 +01:00
Omar Sandoval 2a74c0e4ee libbtrfsutil: relax the privileges of subvolume iterator
We can use the new BTRFS_IOC_GET_SUBVOL_ROOTREF and
BTRFS_IOC_INO_LOOKUP_USER ioctls to allow non-root users to list
subvolumes.

This is based on a patch from Misono Tomohiro but takes a different
approach (mainly, this approach is more similar to the existing tree
search approach).

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-26 16:45:34 +01:00
Omar Sandoval bfe2dc3796 libbtrfsutil: relax the privileges of subvolume_info()
Attempt to use the BTRFS_IOC_GET_SUBVOL_INFO ioctl (added in kernel
4.18) for subvolume_info() if not root. Also, rename
get_subvolume_info_root() -> get_subvolume_info_privileged() for
consistency with further changes.

This is based on a patch from Misono Tomohiro.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-26 16:45:30 +01:00
Omar Sandoval 39ac43a2a4 libbtrfsutil: allow tests to create multiple Btrfs instances
Some upcoming tests will need to create a second Btrfs filesystem, so
add support for this to the test helpers.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-26 16:45:28 +01:00
Omar Sandoval fee45d5421 libbtrfsutil: add test helpers for dropping privileges
These will be used for testing some upcoming changes which allow
unprivileged operations.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-26 16:45:24 +01:00
Omar Sandoval 70126a1570 libbtrfsutil: use SubvolumeIterator as context manager in tests
We're leaking file descriptors, which makes it impossible to clean up
the temporary mount point created by the test.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-26 16:45:22 +01:00
Omar Sandoval c62625046a libbtrfsutil: document qgroup_inherit parameter in Python bindings
This has been supported since day one, but it wasn't documented.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-26 16:45:18 +01:00
Omar Sandoval 5776a70b30 libbtrfsutil: change async parameters to async_ in Python bindings
async became a keyword in Python 3.7, so, e.g., create_subvolume('foo',
async=True) is now a syntax error. Fix it with the Python convention of
adding a trailing underscore to the keyword (async -> async_). This is
what several other Python libraries did to handle this.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-26 16:45:14 +01:00
Omar Sandoval 563affcd42 libbtrfsutil: use top=0 as default for SubvolumeIterator()
Right now, we're defaulting to top=5 (i.e, all subvolumes). The
documented default is top=0 (i.e, only beneath the given path). This is
the expected behavior. Fix it and make the test cases cover it.

Reported-by: Jonathan Lemon <bsd@fb.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-26 16:45:11 +01:00
Omar Sandoval feccd7a818 libbtrfsutil: fix test assumptions about top-level subvolume
Since "btrfs-progs: mkfs: add uuid and otime to ROOT_ITEM of, FS_TREE",
the top-level subvolume has a non-zero UUID, ctime, and otime. Fix the
subvolume_info() test to not check for zero.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-30 22:57:57 +02:00
Omar Sandoval 660adc0e1c libbtrfsutil: use local mkfs.btrfs for tests if it exists
The system might not have mkfs installed at all.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-30 22:54:41 +02:00
Omar Sandoval f239180162 libbtrfsutil: add btrfs_util_deleted_subvolumes()
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-06 11:28:37 +01:00
Omar Sandoval 678da5a7f7 libbtrfsutil: add btrfs_util_delete_subvolume()
We also support recursive deletion using a subvolume iterator.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-06 11:28:37 +01:00
Omar Sandoval cfa89b3082 libbtrfsutil: add btrfs_util_create_snapshot()
Thanks to subvolume iterators, we can also implement recursive snapshot
fairly easily.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-06 11:28:37 +01:00
Omar Sandoval 0b8512b7f5 libbtrfsutil: add subvolume iterator helpers
This is how we can implement stuff like `btrfs subvol list`. Rather than
producing the entire list upfront, the iterator approach uses less
memory in the common case where the whole list is not stored (O(max
subvolume path length)). It supports both pre-order traversal (useful
for, e.g, recursive snapshot) and post-order traversal (useful for
recursive delete).

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-06 11:28:37 +01:00
Omar Sandoval 624e0233e0 libbtrfsutil: add btrfs_util_[gs]et_default_subvolume()
set_default_subvolume() is a trivial ioctl(), but there's no ioctl() for
get_default_subvolume(), so we need to search the root tree.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-06 11:28:36 +01:00
Omar Sandoval 172c0d1a12 libbtrfsutil: add btrfs_util_[gs]et_read_only()
In the future, btrfs_util_[gs]et_subvolume_flags() might be useful, but
since these are the only subvolume flags we've defined in all this time,
this will do for now.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-06 11:28:36 +01:00
Omar Sandoval 0d36261bd5 libbtrfsutil: add btrfs_util_subvolume_info()
This gets the the information in `btrfs subvolume show` from the root
item.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-06 11:28:36 +01:00
Omar Sandoval 8b87811f94 libbtrfsutil: add btrfs_util_subvolume_path()
We can just walk up root backrefs with BTRFS_IOC_TREE_SEARCH and inode
paths with BTRFS_IOC_INO_LOOKUP.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-06 11:28:36 +01:00
Omar Sandoval f676a8ad11 libbtrfsutil: add btrfs_util_create_subvolume()
Doing the ioctl() directly isn't too bad, but passing in a full path is
more convenient than opening the parent and passing the path component.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-06 11:28:36 +01:00
Omar Sandoval 92d4035074 libbtrfsutil: add btrfs_util_is_subvolume() and btrfs_util_subvolume_id()
These are the most trivial helpers in the library and will be used to
implement several of the more involved functions.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-06 11:28:36 +01:00
Omar Sandoval 71d135ef44 libbtrfsutil: fix Python tests
These were broken when the patch series got shuffled around.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-06 11:28:36 +01:00
Omar Sandoval 9615c23d15 libbtrfsutil: add filesystem sync helpers
Namely, sync, start_sync, and wait_sync.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-02-24 01:37:17 +01:00
Omar Sandoval bad4208da3 libbtrfsutil: add qgroup inheritance helpers
We want to hide struct btrfs_qgroup_inherit from the user because that
comes from the Btrfs UAPI headers. Instead, wrap it in a struct
btrfs_util_qgroup_inherit and provide helpers to manipulate it. This
will be used for subvolume and snapshot creation.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-02-24 01:37:17 +01:00
Omar Sandoval 23c01b3c1b libbtrfsutil: add Python bindings
The C libbtrfsutil library isn't very useful for scripting, so we also
want bindings for Python. Writing unit tests in Python is also much
easier than doing so in C. Only Python 3 is supported; if someone really
wants Python 2 support, they can write their own bindings. This commit
is just the scaffolding.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-02-24 01:37:17 +01:00