diff mbox

[v2,14/27] libbtrfsutil: add btrfs_util_deleted_subvolumes()

Message ID ac64e7314e3f716898dd8a7ec7c7657f66ee4c4a.1518720598.git.osandov@fb.com (mailing list archive)
State New, archived
Headers show

Commit Message

Omar Sandoval Feb. 15, 2018, 7:04 p.m. UTC 
From: Omar Sandoval <osandov@fb.com>

Signed-off-by: Omar Sandoval <osandov@fb.com>
---
 libbtrfsutil/btrfsutil.h                    | 21 +++++++
 libbtrfsutil/python/btrfsutilpy.h           |  3 +
 libbtrfsutil/python/module.c                | 30 ++++++++++
 libbtrfsutil/python/qgroup.c                | 17 +-----
 libbtrfsutil/python/subvolume.c             | 30 ++++++++++
 libbtrfsutil/python/tests/test_subvolume.py |  8 +++
 libbtrfsutil/subvolume.c                    | 89 +++++++++++++++++++++++++++++
 7 files changed, 183 insertions(+), 15 deletions(-)

Comments

Misono Tomohiro Feb. 23, 2018, 2:12 a.m. UTC | #1 
On 2018/02/16 4:04, Omar Sandoval wrote:
> From: Omar Sandoval <osandov@fb.com>
> 
> Signed-off-by: Omar Sandoval <osandov@fb.com>
> ---
>  libbtrfsutil/btrfsutil.h                    | 21 +++++++
>  libbtrfsutil/python/btrfsutilpy.h           |  3 +
>  libbtrfsutil/python/module.c                | 30 ++++++++++
>  libbtrfsutil/python/qgroup.c                | 17 +-----
>  libbtrfsutil/python/subvolume.c             | 30 ++++++++++
>  libbtrfsutil/python/tests/test_subvolume.py |  8 +++
>  libbtrfsutil/subvolume.c                    | 89 +++++++++++++++++++++++++++++
>  7 files changed, 183 insertions(+), 15 deletions(-)
> 
> diff --git a/libbtrfsutil/btrfsutil.h b/libbtrfsutil/btrfsutil.h
> index 00c86174..677ab3c1 100644
> --- a/libbtrfsutil/btrfsutil.h
> +++ b/libbtrfsutil/btrfsutil.h
> @@ -534,6 +534,27 @@ enum btrfs_util_error btrfs_util_subvolume_iterator_next_info(struct btrfs_util_
>  							      char **path_ret,
>  							      struct btrfs_util_subvolume_info *subvol);
>  
> +/**
> + * btrfs_util_deleted_subvolumes() - Get a list of subvolume which have been
> + * deleted but not yet cleaned up.
> + * @path: Path on a Btrfs filesystem.
> + * @ids: Returned array of subvolume IDs.
> + * @n: Returned number of IDs in the @ids array.
> + *
> + * This requires appropriate privilege (CAP_SYS_ADMIN).
> + *
> + * Return: %BTRFS_UTIL_OK on success, non-zero error code on failure.
> + */
> +enum btrfs_util_error btrfs_util_deleted_subvolumes(const char *path,
> +						    uint64_t **ids,
> +						    size_t *n);
> +
> +/**
> + * btrfs_util_deleted_subvolumes_fd() - See btrfs_util_deleted_subvolumes().
> + */
> +enum btrfs_util_error btrfs_util_deleted_subvolumes_fd(int fd, uint64_t **ids,
> +						       size_t *n);
> +
>  /**
>   * btrfs_util_create_qgroup_inherit() - Create a qgroup inheritance specifier
>   * for btrfs_util_create_subvolume() or btrfs_util_create_snapshot().
> diff --git a/libbtrfsutil/python/btrfsutilpy.h b/libbtrfsutil/python/btrfsutilpy.h
> index b3ec047f..be5122e2 100644
> --- a/libbtrfsutil/python/btrfsutilpy.h
> +++ b/libbtrfsutil/python/btrfsutilpy.h
> @@ -54,6 +54,8 @@ struct path_arg {
>  int path_converter(PyObject *o, void *p);
>  void path_cleanup(struct path_arg *path);
>  
> +PyObject *list_from_uint64_array(const uint64_t *arr, size_t n);
> +
>  void SetFromBtrfsUtilError(enum btrfs_util_error err);
>  void SetFromBtrfsUtilErrorWithPath(enum btrfs_util_error err,
>  				   struct path_arg *path);
> @@ -72,6 +74,7 @@ PyObject *set_default_subvolume(PyObject *self, PyObject *args, PyObject *kwds);
>  PyObject *create_subvolume(PyObject *self, PyObject *args, PyObject *kwds);
>  PyObject *create_snapshot(PyObject *self, PyObject *args, PyObject *kwds);
>  PyObject *delete_subvolume(PyObject *self, PyObject *args, PyObject *kwds);
> +PyObject *deleted_subvolumes(PyObject *self, PyObject *args, PyObject *kwds);
>  
>  void add_module_constants(PyObject *m);
>  
> diff --git a/libbtrfsutil/python/module.c b/libbtrfsutil/python/module.c
> index e995a1be..eaa062ac 100644
> --- a/libbtrfsutil/python/module.c
> +++ b/libbtrfsutil/python/module.c
> @@ -125,6 +125,29 @@ err:
>  	return 0;
>  }
>  
> +PyObject *list_from_uint64_array(const uint64_t *arr, size_t n)
> +{
> +    PyObject *ret;
> +    size_t i;
> +
> +    ret = PyList_New(n);
> +    if (!ret)
> +	    return NULL;
> +
> +    for (i = 0; i < n; i++) {
> +	    PyObject *tmp;
> +
> +	    tmp = PyLong_FromUnsignedLongLong(arr[i]);
> +	    if (!tmp) {
> +		    Py_DECREF(ret);
> +		    return NULL;
> +	    }
> +	    PyList_SET_ITEM(ret, i, tmp);
> +    }
> +
> +    return ret;
> +}
> +
>  void path_cleanup(struct path_arg *path)
>  {
>  	Py_CLEAR(path->object);
> @@ -214,6 +237,13 @@ static PyMethodDef btrfsutil_methods[] = {
>  	 "path -- string, bytes, or path-like object\n"
>  	 "recursive -- if the given subvolume has child subvolumes, delete\n"
>  	 "them instead of failing"},
> +	{"deleted_subvolumes", (PyCFunction)deleted_subvolumes,
> +	 METH_VARARGS | METH_KEYWORDS,
> +	 "deleted_subvolumes(path)\n\n"
> +	 "Get the list of subvolume IDs which have been deleted but not yet\n"
> +	 "cleaned up\n\n"
> +	 "Arguments:\n"
> +	 "path -- string, bytes, path-like object, or open file descriptor"},
>  	{},
>  };
>  
> diff --git a/libbtrfsutil/python/qgroup.c b/libbtrfsutil/python/qgroup.c
> index 69716d92..44ac5ebc 100644
> --- a/libbtrfsutil/python/qgroup.c
> +++ b/libbtrfsutil/python/qgroup.c
> @@ -55,25 +55,12 @@ static PyObject *QgroupInherit_getattro(QgroupInherit *self, PyObject *nameobj)
>      }
>  
>      if (strcmp(name, "groups") == 0) {
> -	    PyObject *ret, *tmp;
>  	    const uint64_t *arr;
> -	    size_t n, i;
> +	    size_t n;
>  
>  	    btrfs_util_qgroup_inherit_get_groups(self->inherit, &arr, &n);
> -	    ret = PyList_New(n);
> -	    if (!ret)
> -		    return NULL;
> -
> -	    for (i = 0; i < n; i++) {
> -		    tmp = PyLong_FromUnsignedLongLong(arr[i]);
> -		    if (!tmp) {
> -			    Py_DECREF(ret);
> -			    return NULL;
> -		    }
> -		    PyList_SET_ITEM(ret, i, tmp);
> -	    }
>  
> -	    return ret;
> +	    return list_from_uint64_array(arr, n);
>      } else {
>  	    return PyObject_GenericGetAttr((PyObject *)self, nameobj);
>      }
> diff --git a/libbtrfsutil/python/subvolume.c b/libbtrfsutil/python/subvolume.c
> index eb3f6e27..069e606b 100644
> --- a/libbtrfsutil/python/subvolume.c
> +++ b/libbtrfsutil/python/subvolume.c
> @@ -425,6 +425,36 @@ PyObject *delete_subvolume(PyObject *self, PyObject *args, PyObject *kwds)
>  	Py_RETURN_NONE;
>  }
>  
> +PyObject *deleted_subvolumes(PyObject *self, PyObject *args, PyObject *kwds)
> +{
> +	static char *keywords[] = {"path", NULL};
> +	struct path_arg path = {.allow_fd = true};
> +	PyObject *ret;
> +	uint64_t *ids;
> +	size_t n;
> +	enum btrfs_util_error err;
> +
> +	if (!PyArg_ParseTupleAndKeywords(args, kwds, "O&:deleted_subvolumes",
> +					 keywords, &path_converter, &path))
> +		return NULL;
> +
> +	if (path.path)
> +		err = btrfs_util_deleted_subvolumes(path.path, &ids, &n);
> +	else
> +		err = btrfs_util_deleted_subvolumes_fd(path.fd, &ids, &n);
> +	if (err) {
> +		SetFromBtrfsUtilErrorWithPath(err, &path);
> +		path_cleanup(&path);
> +		return NULL;
> +	}
> +
> +	path_cleanup(&path);
> +
> +	ret = list_from_uint64_array(ids, n);
> +	free(ids);
> +	return ret;
> +}
> +
>  typedef struct {
>  	PyObject_HEAD
>  	struct btrfs_util_subvolume_iterator *iter;
> diff --git a/libbtrfsutil/python/tests/test_subvolume.py b/libbtrfsutil/python/tests/test_subvolume.py
> index 08083abe..a46d4a34 100644
> --- a/libbtrfsutil/python/tests/test_subvolume.py
> +++ b/libbtrfsutil/python/tests/test_subvolume.py
> @@ -318,6 +318,14 @@ class TestSubvolume(BtrfsTestCase):
>          btrfsutil.delete_subvolume(subvol + '5', recursive=True)
>          self.assertFalse(os.path.exists(subvol + '5'))
>  
> +    def test_deleted_subvolumes(self):
> +        subvol = os.path.join(self.mountpoint, 'subvol')
> +        btrfsutil.create_subvolume(subvol + '1')
> +        btrfsutil.delete_subvolume(subvol + '1')
> +        for arg in self.path_or_fd(self.mountpoint):
> +            with self.subTest(type=type(arg)):
> +                self.assertEqual(btrfsutil.deleted_subvolumes(arg), [256])
> +
>      def test_subvolume_iterator(self):
>          pwd = os.getcwd()
>          try:
> diff --git a/libbtrfsutil/subvolume.c b/libbtrfsutil/subvolume.c
> index 908e71db..4ae581b2 100644
> --- a/libbtrfsutil/subvolume.c
> +++ b/libbtrfsutil/subvolume.c
> @@ -1277,3 +1277,92 @@ PUBLIC enum btrfs_util_error btrfs_util_subvolume_iterator_next_info(struct btrf
>  
>  	return btrfs_util_subvolume_info_fd(iter->fd, id, subvol);
>  }
> +
> +PUBLIC enum btrfs_util_error btrfs_util_deleted_subvolumes(const char *path,
> +							   uint64_t **ids,
> +							   size_t *n)
> +{
> +	enum btrfs_util_error err;
> +	int fd;
> +
> +	fd = open(path, O_RDONLY);
> +	if (fd == -1)
> +		return BTRFS_UTIL_ERROR_OPEN_FAILED;
> +
> +	err = btrfs_util_deleted_subvolumes_fd(fd, ids, n);
> +	SAVE_ERRNO_AND_CLOSE(fd);
> +	return err;
> +}
> +
> +PUBLIC enum btrfs_util_error btrfs_util_deleted_subvolumes_fd(int fd,
> +							      uint64_t **ids,
> +							      size_t *n)
> +{
> +	size_t capacity = 0;
> +	struct btrfs_ioctl_search_args search = {
> +		.key = {
> +			.tree_id = BTRFS_ROOT_TREE_OBJECTID,
> +			.min_objectid = BTRFS_ORPHAN_OBJECTID,
> +			.max_objectid = BTRFS_ORPHAN_OBJECTID,
> +			.min_type = BTRFS_ORPHAN_ITEM_KEY,
> +			.max_type = BTRFS_ORPHAN_ITEM_KEY,
> +			.min_offset = 0,
> +			.max_offset = UINT64_MAX,
> +			.min_transid = 0,
> +			.max_transid = UINT64_MAX,
> +			.nr_items = 0,
> +		},
> +	};
It seems btrfs_util_deleted_subvolume() does not works perfectly.

Above search will return all ORPHAN_ITEM but some may be of free space cache inode (correct me if I'm wrong).
Since this is a public function, we should filter those non-subvolume objectid by checking root tree again.
I think this is the reason of failure of misc-test/013 after merging 26th patch.

> +	enum btrfs_util_error err;
> +	size_t items_pos = 0, buf_off = 0;
> +	int ret;
> +
> +	*ids = NULL;
> +	*n = 0;
> +	for (;;) {
> +		const struct btrfs_ioctl_search_header *header;
> +
> +		if (items_pos >= search.key.nr_items) {
> +			search.key.nr_items = 4096;
> +			ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &search);
> +			if (ret == -1) {
> +				err = BTRFS_UTIL_ERROR_SEARCH_FAILED;
> +				goto out;
> +			}
> +			items_pos = 0;
> +			buf_off = 0;
> +
> +			if (search.key.nr_items == 0)
> +				break;
> +		}
> +
> +		header = (struct btrfs_ioctl_search_header *)(search.buf + buf_off);
> +		if (*n >= capacity) {
> +			size_t new_capacity = capacity ? capacity * 2 : 1;
> +			uint64_t *new_ids;
> +
> +			new_ids = reallocarray(*ids, new_capacity,
> +					       sizeof(**ids));
> +			if (!new_ids)
> +				return BTRFS_UTIL_ERROR_NO_MEMORY;
> +
> +			*ids = new_ids;
> +			capacity = new_capacity;
> +		}
> +
> +		(*ids)[(*n)++] = header->offset;
> +
> +		items_pos++;
> +		buf_off += sizeof(*header) + header->len;
> +		search.key.min_offset = header->offset + 1;
> +	}
> +
> +	err = BTRFS_UTIL_OK;
> +out:
> +	if (err) {
> +		free(ids);
> +		*ids = NULL;
> +		*n = 0;
> +	}
> +	return err;
> +}
> 

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Omar Sandoval Feb. 23, 2018, 11:33 p.m. UTC | #2 
On Fri, Feb 23, 2018 at 11:12:56AM +0900, Misono, Tomohiro wrote:
> 
> On 2018/02/16 4:04, Omar Sandoval wrote:
> > From: Omar Sandoval <osandov@fb.com>
> > 
> > Signed-off-by: Omar Sandoval <osandov@fb.com>
> > ---
> >  libbtrfsutil/btrfsutil.h                    | 21 +++++++
> >  libbtrfsutil/python/btrfsutilpy.h           |  3 +
> >  libbtrfsutil/python/module.c                | 30 ++++++++++
> >  libbtrfsutil/python/qgroup.c                | 17 +-----
> >  libbtrfsutil/python/subvolume.c             | 30 ++++++++++
> >  libbtrfsutil/python/tests/test_subvolume.py |  8 +++
> >  libbtrfsutil/subvolume.c                    | 89 +++++++++++++++++++++++++++++
> >  7 files changed, 183 insertions(+), 15 deletions(-)
> > 
> > diff --git a/libbtrfsutil/btrfsutil.h b/libbtrfsutil/btrfsutil.h
> > index 00c86174..677ab3c1 100644
> > --- a/libbtrfsutil/btrfsutil.h
> > +++ b/libbtrfsutil/btrfsutil.h
> > @@ -534,6 +534,27 @@ enum btrfs_util_error btrfs_util_subvolume_iterator_next_info(struct btrfs_util_
> >  							      char **path_ret,
> >  							      struct btrfs_util_subvolume_info *subvol);
> >  
> > +/**
> > + * btrfs_util_deleted_subvolumes() - Get a list of subvolume which have been
> > + * deleted but not yet cleaned up.
> > + * @path: Path on a Btrfs filesystem.
> > + * @ids: Returned array of subvolume IDs.
> > + * @n: Returned number of IDs in the @ids array.
> > + *
> > + * This requires appropriate privilege (CAP_SYS_ADMIN).
> > + *
> > + * Return: %BTRFS_UTIL_OK on success, non-zero error code on failure.
> > + */
> > +enum btrfs_util_error btrfs_util_deleted_subvolumes(const char *path,
> > +						    uint64_t **ids,
> > +						    size_t *n);
> > +
> > +/**
> > + * btrfs_util_deleted_subvolumes_fd() - See btrfs_util_deleted_subvolumes().
> > + */
> > +enum btrfs_util_error btrfs_util_deleted_subvolumes_fd(int fd, uint64_t **ids,
> > +						       size_t *n);
> > +
> >  /**
> >   * btrfs_util_create_qgroup_inherit() - Create a qgroup inheritance specifier
> >   * for btrfs_util_create_subvolume() or btrfs_util_create_snapshot().
> > diff --git a/libbtrfsutil/python/btrfsutilpy.h b/libbtrfsutil/python/btrfsutilpy.h
> > index b3ec047f..be5122e2 100644
> > --- a/libbtrfsutil/python/btrfsutilpy.h
> > +++ b/libbtrfsutil/python/btrfsutilpy.h
> > @@ -54,6 +54,8 @@ struct path_arg {
> >  int path_converter(PyObject *o, void *p);
> >  void path_cleanup(struct path_arg *path);
> >  
> > +PyObject *list_from_uint64_array(const uint64_t *arr, size_t n);
> > +
> >  void SetFromBtrfsUtilError(enum btrfs_util_error err);
> >  void SetFromBtrfsUtilErrorWithPath(enum btrfs_util_error err,
> >  				   struct path_arg *path);
> > @@ -72,6 +74,7 @@ PyObject *set_default_subvolume(PyObject *self, PyObject *args, PyObject *kwds);
> >  PyObject *create_subvolume(PyObject *self, PyObject *args, PyObject *kwds);
> >  PyObject *create_snapshot(PyObject *self, PyObject *args, PyObject *kwds);
> >  PyObject *delete_subvolume(PyObject *self, PyObject *args, PyObject *kwds);
> > +PyObject *deleted_subvolumes(PyObject *self, PyObject *args, PyObject *kwds);
> >  
> >  void add_module_constants(PyObject *m);
> >  
> > diff --git a/libbtrfsutil/python/module.c b/libbtrfsutil/python/module.c
> > index e995a1be..eaa062ac 100644
> > --- a/libbtrfsutil/python/module.c
> > +++ b/libbtrfsutil/python/module.c
> > @@ -125,6 +125,29 @@ err:
> >  	return 0;
> >  }
> >  
> > +PyObject *list_from_uint64_array(const uint64_t *arr, size_t n)
> > +{
> > +    PyObject *ret;
> > +    size_t i;
> > +
> > +    ret = PyList_New(n);
> > +    if (!ret)
> > +	    return NULL;
> > +
> > +    for (i = 0; i < n; i++) {
> > +	    PyObject *tmp;
> > +
> > +	    tmp = PyLong_FromUnsignedLongLong(arr[i]);
> > +	    if (!tmp) {
> > +		    Py_DECREF(ret);
> > +		    return NULL;
> > +	    }
> > +	    PyList_SET_ITEM(ret, i, tmp);
> > +    }
> > +
> > +    return ret;
> > +}
> > +
> >  void path_cleanup(struct path_arg *path)
> >  {
> >  	Py_CLEAR(path->object);
> > @@ -214,6 +237,13 @@ static PyMethodDef btrfsutil_methods[] = {
> >  	 "path -- string, bytes, or path-like object\n"
> >  	 "recursive -- if the given subvolume has child subvolumes, delete\n"
> >  	 "them instead of failing"},
> > +	{"deleted_subvolumes", (PyCFunction)deleted_subvolumes,
> > +	 METH_VARARGS | METH_KEYWORDS,
> > +	 "deleted_subvolumes(path)\n\n"
> > +	 "Get the list of subvolume IDs which have been deleted but not yet\n"
> > +	 "cleaned up\n\n"
> > +	 "Arguments:\n"
> > +	 "path -- string, bytes, path-like object, or open file descriptor"},
> >  	{},
> >  };
> >  
> > diff --git a/libbtrfsutil/python/qgroup.c b/libbtrfsutil/python/qgroup.c
> > index 69716d92..44ac5ebc 100644
> > --- a/libbtrfsutil/python/qgroup.c
> > +++ b/libbtrfsutil/python/qgroup.c
> > @@ -55,25 +55,12 @@ static PyObject *QgroupInherit_getattro(QgroupInherit *self, PyObject *nameobj)
> >      }
> >  
> >      if (strcmp(name, "groups") == 0) {
> > -	    PyObject *ret, *tmp;
> >  	    const uint64_t *arr;
> > -	    size_t n, i;
> > +	    size_t n;
> >  
> >  	    btrfs_util_qgroup_inherit_get_groups(self->inherit, &arr, &n);
> > -	    ret = PyList_New(n);
> > -	    if (!ret)
> > -		    return NULL;
> > -
> > -	    for (i = 0; i < n; i++) {
> > -		    tmp = PyLong_FromUnsignedLongLong(arr[i]);
> > -		    if (!tmp) {
> > -			    Py_DECREF(ret);
> > -			    return NULL;
> > -		    }
> > -		    PyList_SET_ITEM(ret, i, tmp);
> > -	    }
> >  
> > -	    return ret;
> > +	    return list_from_uint64_array(arr, n);
> >      } else {
> >  	    return PyObject_GenericGetAttr((PyObject *)self, nameobj);
> >      }
> > diff --git a/libbtrfsutil/python/subvolume.c b/libbtrfsutil/python/subvolume.c
> > index eb3f6e27..069e606b 100644
> > --- a/libbtrfsutil/python/subvolume.c
> > +++ b/libbtrfsutil/python/subvolume.c
> > @@ -425,6 +425,36 @@ PyObject *delete_subvolume(PyObject *self, PyObject *args, PyObject *kwds)
> >  	Py_RETURN_NONE;
> >  }
> >  
> > +PyObject *deleted_subvolumes(PyObject *self, PyObject *args, PyObject *kwds)
> > +{
> > +	static char *keywords[] = {"path", NULL};
> > +	struct path_arg path = {.allow_fd = true};
> > +	PyObject *ret;
> > +	uint64_t *ids;
> > +	size_t n;
> > +	enum btrfs_util_error err;
> > +
> > +	if (!PyArg_ParseTupleAndKeywords(args, kwds, "O&:deleted_subvolumes",
> > +					 keywords, &path_converter, &path))
> > +		return NULL;
> > +
> > +	if (path.path)
> > +		err = btrfs_util_deleted_subvolumes(path.path, &ids, &n);
> > +	else
> > +		err = btrfs_util_deleted_subvolumes_fd(path.fd, &ids, &n);
> > +	if (err) {
> > +		SetFromBtrfsUtilErrorWithPath(err, &path);
> > +		path_cleanup(&path);
> > +		return NULL;
> > +	}
> > +
> > +	path_cleanup(&path);
> > +
> > +	ret = list_from_uint64_array(ids, n);
> > +	free(ids);
> > +	return ret;
> > +}
> > +
> >  typedef struct {
> >  	PyObject_HEAD
> >  	struct btrfs_util_subvolume_iterator *iter;
> > diff --git a/libbtrfsutil/python/tests/test_subvolume.py b/libbtrfsutil/python/tests/test_subvolume.py
> > index 08083abe..a46d4a34 100644
> > --- a/libbtrfsutil/python/tests/test_subvolume.py
> > +++ b/libbtrfsutil/python/tests/test_subvolume.py
> > @@ -318,6 +318,14 @@ class TestSubvolume(BtrfsTestCase):
> >          btrfsutil.delete_subvolume(subvol + '5', recursive=True)
> >          self.assertFalse(os.path.exists(subvol + '5'))
> >  
> > +    def test_deleted_subvolumes(self):
> > +        subvol = os.path.join(self.mountpoint, 'subvol')
> > +        btrfsutil.create_subvolume(subvol + '1')
> > +        btrfsutil.delete_subvolume(subvol + '1')
> > +        for arg in self.path_or_fd(self.mountpoint):
> > +            with self.subTest(type=type(arg)):
> > +                self.assertEqual(btrfsutil.deleted_subvolumes(arg), [256])
> > +
> >      def test_subvolume_iterator(self):
> >          pwd = os.getcwd()
> >          try:
> > diff --git a/libbtrfsutil/subvolume.c b/libbtrfsutil/subvolume.c
> > index 908e71db..4ae581b2 100644
> > --- a/libbtrfsutil/subvolume.c
> > +++ b/libbtrfsutil/subvolume.c
> > @@ -1277,3 +1277,92 @@ PUBLIC enum btrfs_util_error btrfs_util_subvolume_iterator_next_info(struct btrf
> >  
> >  	return btrfs_util_subvolume_info_fd(iter->fd, id, subvol);
> >  }
> > +
> > +PUBLIC enum btrfs_util_error btrfs_util_deleted_subvolumes(const char *path,
> > +							   uint64_t **ids,
> > +							   size_t *n)
> > +{
> > +	enum btrfs_util_error err;
> > +	int fd;
> > +
> > +	fd = open(path, O_RDONLY);
> > +	if (fd == -1)
> > +		return BTRFS_UTIL_ERROR_OPEN_FAILED;
> > +
> > +	err = btrfs_util_deleted_subvolumes_fd(fd, ids, n);
> > +	SAVE_ERRNO_AND_CLOSE(fd);
> > +	return err;
> > +}
> > +
> > +PUBLIC enum btrfs_util_error btrfs_util_deleted_subvolumes_fd(int fd,
> > +							      uint64_t **ids,
> > +							      size_t *n)
> > +{
> > +	size_t capacity = 0;
> > +	struct btrfs_ioctl_search_args search = {
> > +		.key = {
> > +			.tree_id = BTRFS_ROOT_TREE_OBJECTID,
> > +			.min_objectid = BTRFS_ORPHAN_OBJECTID,
> > +			.max_objectid = BTRFS_ORPHAN_OBJECTID,
> > +			.min_type = BTRFS_ORPHAN_ITEM_KEY,
> > +			.max_type = BTRFS_ORPHAN_ITEM_KEY,
> > +			.min_offset = 0,
> > +			.max_offset = UINT64_MAX,
> > +			.min_transid = 0,
> > +			.max_transid = UINT64_MAX,
> > +			.nr_items = 0,
> > +		},
> > +	};
> It seems btrfs_util_deleted_subvolume() does not works perfectly.
> 
> Above search will return all ORPHAN_ITEM but some may be of free space cache inode (correct me if I'm wrong).
> Since this is a public function, we should filter those non-subvolume objectid by checking root tree again.
> I think this is the reason of failure of misc-test/013 after merging 26th patch.

So looking at the code that this replaces, I don't see the difference:

static int enumerate_dead_subvols(int fd, u64 **ids)
{
	int ret;
	struct btrfs_ioctl_search_args args;
	struct btrfs_ioctl_search_key *sk = &args.key;
	int idx = 0;
	int count = 0;

	memset(&args, 0, sizeof(args));

	sk->tree_id = BTRFS_ROOT_TREE_OBJECTID;
	sk->min_objectid = BTRFS_ORPHAN_OBJECTID;
	sk->max_objectid = BTRFS_ORPHAN_OBJECTID;
	sk->min_type = BTRFS_ORPHAN_ITEM_KEY;
	sk->max_type = BTRFS_ORPHAN_ITEM_KEY;
	sk->min_offset = 0;
	sk->max_offset = (u64)-1;
	sk->min_transid = 0;
	sk->max_transid = (u64)-1;
	sk->nr_items = 4096;

	*ids = NULL;
	while (1) {
		struct btrfs_ioctl_search_header *sh;
		unsigned long off;
		int i;

		ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args);
		if (ret < 0)
			return -errno;

		if (!sk->nr_items)
			return idx;

		off = 0;
		for (i = 0; i < sk->nr_items; i++) {
			sh = (struct btrfs_ioctl_search_header*)(args.buf + off);
			off += sizeof(*sh);

			if (btrfs_search_header_type(sh)
			    == BTRFS_ORPHAN_ITEM_KEY) {
				if (idx >= count) {
					u64 *newids;

					count += SUBVOL_ID_BATCH;
					newids = (u64*)realloc(*ids,
							count * sizeof(u64));
					if (!newids)
						return -ENOMEM;
					*ids = newids;
				}
				(*ids)[idx] = btrfs_search_header_offset(sh);
				idx++;
			}
			off += btrfs_search_header_len(sh);

			sk->min_objectid = btrfs_search_header_objectid(sh);
			sk->min_type = btrfs_search_header_type(sh);
			sk->min_offset = btrfs_search_header_offset(sh);
		}
		if (sk->min_offset < (u64)-1)
			sk->min_offset++;
		else
			break;
		if (sk->min_type != BTRFS_ORPHAN_ITEM_KEY)
			break;
		if (sk->min_objectid != BTRFS_ORPHAN_OBJECTID)
			break;
	}

	return idx;
}

This function does the same exact search, as far as I can tell. What does the
test failure look like? I'll try to reproduce it on my side.

> > +	enum btrfs_util_error err;
> > +	size_t items_pos = 0, buf_off = 0;
> > +	int ret;
> > +
> > +	*ids = NULL;
> > +	*n = 0;
> > +	for (;;) {
> > +		const struct btrfs_ioctl_search_header *header;
> > +
> > +		if (items_pos >= search.key.nr_items) {
> > +			search.key.nr_items = 4096;
> > +			ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &search);
> > +			if (ret == -1) {
> > +				err = BTRFS_UTIL_ERROR_SEARCH_FAILED;
> > +				goto out;
> > +			}
> > +			items_pos = 0;
> > +			buf_off = 0;
> > +
> > +			if (search.key.nr_items == 0)
> > +				break;
> > +		}
> > +
> > +		header = (struct btrfs_ioctl_search_header *)(search.buf + buf_off);
> > +		if (*n >= capacity) {
> > +			size_t new_capacity = capacity ? capacity * 2 : 1;
> > +			uint64_t *new_ids;
> > +
> > +			new_ids = reallocarray(*ids, new_capacity,
> > +					       sizeof(**ids));
> > +			if (!new_ids)
> > +				return BTRFS_UTIL_ERROR_NO_MEMORY;
> > +
> > +			*ids = new_ids;
> > +			capacity = new_capacity;
> > +		}
> > +
> > +		(*ids)[(*n)++] = header->offset;
> > +
> > +		items_pos++;
> > +		buf_off += sizeof(*header) + header->len;
> > +		search.key.min_offset = header->offset + 1;
> > +	}
> > +
> > +	err = BTRFS_UTIL_OK;
> > +out:
> > +	if (err) {
> > +		free(ids);
> > +		*ids = NULL;
> > +		*n = 0;
> > +	}
> > +	return err;
> > +}
> > 
> 
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diff mbox

Patch

diff --git a/libbtrfsutil/btrfsutil.h b/libbtrfsutil/btrfsutil.h
index 00c86174..677ab3c1 100644
--- a/libbtrfsutil/btrfsutil.h
+++ b/libbtrfsutil/btrfsutil.h
@@ -534,6 +534,27 @@  enum btrfs_util_error btrfs_util_subvolume_iterator_next_info(struct btrfs_util_
 							      char **path_ret,
 							      struct btrfs_util_subvolume_info *subvol);
 
+/**
+ * btrfs_util_deleted_subvolumes() - Get a list of subvolume which have been
+ * deleted but not yet cleaned up.
+ * @path: Path on a Btrfs filesystem.
+ * @ids: Returned array of subvolume IDs.
+ * @n: Returned number of IDs in the @ids array.
+ *
+ * This requires appropriate privilege (CAP_SYS_ADMIN).
+ *
+ * Return: %BTRFS_UTIL_OK on success, non-zero error code on failure.
+ */
+enum btrfs_util_error btrfs_util_deleted_subvolumes(const char *path,
+						    uint64_t **ids,
+						    size_t *n);
+
+/**
+ * btrfs_util_deleted_subvolumes_fd() - See btrfs_util_deleted_subvolumes().
+ */
+enum btrfs_util_error btrfs_util_deleted_subvolumes_fd(int fd, uint64_t **ids,
+						       size_t *n);
+
 /**
  * btrfs_util_create_qgroup_inherit() - Create a qgroup inheritance specifier
  * for btrfs_util_create_subvolume() or btrfs_util_create_snapshot().
diff --git a/libbtrfsutil/python/btrfsutilpy.h b/libbtrfsutil/python/btrfsutilpy.h
index b3ec047f..be5122e2 100644
--- a/libbtrfsutil/python/btrfsutilpy.h
+++ b/libbtrfsutil/python/btrfsutilpy.h
@@ -54,6 +54,8 @@  struct path_arg {
 int path_converter(PyObject *o, void *p);
 void path_cleanup(struct path_arg *path);
 
+PyObject *list_from_uint64_array(const uint64_t *arr, size_t n);
+
 void SetFromBtrfsUtilError(enum btrfs_util_error err);
 void SetFromBtrfsUtilErrorWithPath(enum btrfs_util_error err,
 				   struct path_arg *path);
@@ -72,6 +74,7 @@  PyObject *set_default_subvolume(PyObject *self, PyObject *args, PyObject *kwds);
 PyObject *create_subvolume(PyObject *self, PyObject *args, PyObject *kwds);
 PyObject *create_snapshot(PyObject *self, PyObject *args, PyObject *kwds);
 PyObject *delete_subvolume(PyObject *self, PyObject *args, PyObject *kwds);
+PyObject *deleted_subvolumes(PyObject *self, PyObject *args, PyObject *kwds);
 
 void add_module_constants(PyObject *m);
 
diff --git a/libbtrfsutil/python/module.c b/libbtrfsutil/python/module.c
index e995a1be..eaa062ac 100644
--- a/libbtrfsutil/python/module.c
+++ b/libbtrfsutil/python/module.c
@@ -125,6 +125,29 @@  err:
 	return 0;
 }
 
+PyObject *list_from_uint64_array(const uint64_t *arr, size_t n)
+{
+    PyObject *ret;
+    size_t i;
+
+    ret = PyList_New(n);
+    if (!ret)
+	    return NULL;
+
+    for (i = 0; i < n; i++) {
+	    PyObject *tmp;
+
+	    tmp = PyLong_FromUnsignedLongLong(arr[i]);
+	    if (!tmp) {
+		    Py_DECREF(ret);
+		    return NULL;
+	    }
+	    PyList_SET_ITEM(ret, i, tmp);
+    }
+
+    return ret;
+}
+
 void path_cleanup(struct path_arg *path)
 {
 	Py_CLEAR(path->object);
@@ -214,6 +237,13 @@  static PyMethodDef btrfsutil_methods[] = {
 	 "path -- string, bytes, or path-like object\n"
 	 "recursive -- if the given subvolume has child subvolumes, delete\n"
 	 "them instead of failing"},
+	{"deleted_subvolumes", (PyCFunction)deleted_subvolumes,
+	 METH_VARARGS | METH_KEYWORDS,
+	 "deleted_subvolumes(path)\n\n"
+	 "Get the list of subvolume IDs which have been deleted but not yet\n"
+	 "cleaned up\n\n"
+	 "Arguments:\n"
+	 "path -- string, bytes, path-like object, or open file descriptor"},
 	{},
 };
 
diff --git a/libbtrfsutil/python/qgroup.c b/libbtrfsutil/python/qgroup.c
index 69716d92..44ac5ebc 100644
--- a/libbtrfsutil/python/qgroup.c
+++ b/libbtrfsutil/python/qgroup.c
@@ -55,25 +55,12 @@  static PyObject *QgroupInherit_getattro(QgroupInherit *self, PyObject *nameobj)
     }
 
     if (strcmp(name, "groups") == 0) {
-	    PyObject *ret, *tmp;
 	    const uint64_t *arr;
-	    size_t n, i;
+	    size_t n;
 
 	    btrfs_util_qgroup_inherit_get_groups(self->inherit, &arr, &n);
-	    ret = PyList_New(n);
-	    if (!ret)
-		    return NULL;
-
-	    for (i = 0; i < n; i++) {
-		    tmp = PyLong_FromUnsignedLongLong(arr[i]);
-		    if (!tmp) {
-			    Py_DECREF(ret);
-			    return NULL;
-		    }
-		    PyList_SET_ITEM(ret, i, tmp);
-	    }
 
-	    return ret;
+	    return list_from_uint64_array(arr, n);
     } else {
 	    return PyObject_GenericGetAttr((PyObject *)self, nameobj);
     }
diff --git a/libbtrfsutil/python/subvolume.c b/libbtrfsutil/python/subvolume.c
index eb3f6e27..069e606b 100644
--- a/libbtrfsutil/python/subvolume.c
+++ b/libbtrfsutil/python/subvolume.c
@@ -425,6 +425,36 @@  PyObject *delete_subvolume(PyObject *self, PyObject *args, PyObject *kwds)
 	Py_RETURN_NONE;
 }
 
+PyObject *deleted_subvolumes(PyObject *self, PyObject *args, PyObject *kwds)
+{
+	static char *keywords[] = {"path", NULL};
+	struct path_arg path = {.allow_fd = true};
+	PyObject *ret;
+	uint64_t *ids;
+	size_t n;
+	enum btrfs_util_error err;
+
+	if (!PyArg_ParseTupleAndKeywords(args, kwds, "O&:deleted_subvolumes",
+					 keywords, &path_converter, &path))
+		return NULL;
+
+	if (path.path)
+		err = btrfs_util_deleted_subvolumes(path.path, &ids, &n);
+	else
+		err = btrfs_util_deleted_subvolumes_fd(path.fd, &ids, &n);
+	if (err) {
+		SetFromBtrfsUtilErrorWithPath(err, &path);
+		path_cleanup(&path);
+		return NULL;
+	}
+
+	path_cleanup(&path);
+
+	ret = list_from_uint64_array(ids, n);
+	free(ids);
+	return ret;
+}
+
 typedef struct {
 	PyObject_HEAD
 	struct btrfs_util_subvolume_iterator *iter;
diff --git a/libbtrfsutil/python/tests/test_subvolume.py b/libbtrfsutil/python/tests/test_subvolume.py
index 08083abe..a46d4a34 100644
--- a/libbtrfsutil/python/tests/test_subvolume.py
+++ b/libbtrfsutil/python/tests/test_subvolume.py
@@ -318,6 +318,14 @@  class TestSubvolume(BtrfsTestCase):
         btrfsutil.delete_subvolume(subvol + '5', recursive=True)
         self.assertFalse(os.path.exists(subvol + '5'))
 
+    def test_deleted_subvolumes(self):
+        subvol = os.path.join(self.mountpoint, 'subvol')
+        btrfsutil.create_subvolume(subvol + '1')
+        btrfsutil.delete_subvolume(subvol + '1')
+        for arg in self.path_or_fd(self.mountpoint):
+            with self.subTest(type=type(arg)):
+                self.assertEqual(btrfsutil.deleted_subvolumes(arg), [256])
+
     def test_subvolume_iterator(self):
         pwd = os.getcwd()
         try:
diff --git a/libbtrfsutil/subvolume.c b/libbtrfsutil/subvolume.c
index 908e71db..4ae581b2 100644
--- a/libbtrfsutil/subvolume.c
+++ b/libbtrfsutil/subvolume.c
@@ -1277,3 +1277,92 @@  PUBLIC enum btrfs_util_error btrfs_util_subvolume_iterator_next_info(struct btrf
 
 	return btrfs_util_subvolume_info_fd(iter->fd, id, subvol);
 }
+
+PUBLIC enum btrfs_util_error btrfs_util_deleted_subvolumes(const char *path,
+							   uint64_t **ids,
+							   size_t *n)
+{
+	enum btrfs_util_error err;
+	int fd;
+
+	fd = open(path, O_RDONLY);
+	if (fd == -1)
+		return BTRFS_UTIL_ERROR_OPEN_FAILED;
+
+	err = btrfs_util_deleted_subvolumes_fd(fd, ids, n);
+	SAVE_ERRNO_AND_CLOSE(fd);
+	return err;
+}
+
+PUBLIC enum btrfs_util_error btrfs_util_deleted_subvolumes_fd(int fd,
+							      uint64_t **ids,
+							      size_t *n)
+{
+	size_t capacity = 0;
+	struct btrfs_ioctl_search_args search = {
+		.key = {
+			.tree_id = BTRFS_ROOT_TREE_OBJECTID,
+			.min_objectid = BTRFS_ORPHAN_OBJECTID,
+			.max_objectid = BTRFS_ORPHAN_OBJECTID,
+			.min_type = BTRFS_ORPHAN_ITEM_KEY,
+			.max_type = BTRFS_ORPHAN_ITEM_KEY,
+			.min_offset = 0,
+			.max_offset = UINT64_MAX,
+			.min_transid = 0,
+			.max_transid = UINT64_MAX,
+			.nr_items = 0,
+		},
+	};
+	enum btrfs_util_error err;
+	size_t items_pos = 0, buf_off = 0;
+	int ret;
+
+	*ids = NULL;
+	*n = 0;
+	for (;;) {
+		const struct btrfs_ioctl_search_header *header;
+
+		if (items_pos >= search.key.nr_items) {
+			search.key.nr_items = 4096;
+			ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &search);
+			if (ret == -1) {
+				err = BTRFS_UTIL_ERROR_SEARCH_FAILED;
+				goto out;
+			}
+			items_pos = 0;
+			buf_off = 0;
+
+			if (search.key.nr_items == 0)
+				break;
+		}
+
+		header = (struct btrfs_ioctl_search_header *)(search.buf + buf_off);
+		if (*n >= capacity) {
+			size_t new_capacity = capacity ? capacity * 2 : 1;
+			uint64_t *new_ids;
+
+			new_ids = reallocarray(*ids, new_capacity,
+					       sizeof(**ids));
+			if (!new_ids)
+				return BTRFS_UTIL_ERROR_NO_MEMORY;
+
+			*ids = new_ids;
+			capacity = new_capacity;
+		}
+
+		(*ids)[(*n)++] = header->offset;
+
+		items_pos++;
+		buf_off += sizeof(*header) + header->len;
+		search.key.min_offset = header->offset + 1;
+	}
+
+	err = BTRFS_UTIL_OK;
+out:
+	if (err) {
+		free(ids);
+		*ids = NULL;
+		*n = 0;
+	}
+	return err;
+}