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>
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>
btrfsutil.h and the Python docstrings are thorough, but I've gotten a
couple of requests for a high-level overview of the available interfaces
and example usages. Add them to README.md.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
With the previous few fixes and features, we should bump the minor
version.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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>
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>
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>
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>
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>
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>
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>
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>
Found using -Wmissing-prototypes in GCC. This should improve LTO
behavior.
Note that set_free_space_tree_thresholds is an unused function. Adding
inline seems to remove the unused function warning.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Rosen Penev <rosenp@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Factor out main logic of btrfs_util_subvolume_info_fd(). This is a
preparation work to relax the root privilege of this function. No
functional changes.
Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Copy and add 3 definitions of new unprivileged ioctls:
* BTRFS_IOC_GET_SUBVOL_INFO
* BTRFS_IOC_GET_SUBVOL_ROOTREF
* BTRFS_IOC_INO_LOOKUP_USER
from kernel definitions. They will be used to implement the version
of "btrfs subvolume list/show" that will not require root privileges.
Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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>
If we fail to reallocate the ID array, we still need to free it.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Deleted free space cache inodes also get an orphan item in the root
tree, but we shouldn't report those as deleted subvolumes. Deleted
subvolumes will still have the root item, so we can just do an extra
tree search.
Reported-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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>
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>
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>
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>
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>
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>
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>
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>
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>
Systems with older kernels won't have these available, and the copies in
btrfs-progs aren't quite compatible, so for now, let's just copy these
in. We can potentially deduplicate some of this in the future.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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>
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>
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>
Currently, users wishing to manage Btrfs filesystems programatically
have to shell out to btrfs-progs and parse the output. This isn't ideal.
The goal of libbtrfsutil is to provide a library version of as many of
the operations of btrfs-progs as possible and to migrate btrfs-progs to
use it.
Rather than simply refactoring the existing btrfs-progs code, the code
has to be written from scratch for a couple of reasons:
* A lot of the btrfs-progs code was not designed with a nice library API
in mind in terms of reusability, naming, and error reporting.
* libbtrfsutil is licensed under the LGPL, whereas btrfs-progs is under
the GPL, which makes it dubious to directly copy or move the code.
Eventually, most of the low-level btrfs-progs code should either live in
libbtrfsutil or the shared kernel/userspace filesystem code, and
btrfs-progs will just be the CLI wrapper.
This first commit just includes the build system changes, license,
README, and error reporting helper.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Omar Sandoval
Josh Soref
Rosen Penev
Misono Tomohiro
David Sterba