Richard W.M. Jones
2019-Nov-25 10:03 UTC
[Libguestfs] [PATCH nbdkit v2 0/7] Implement nbdkit API v2 for Python plugins.
v3 was here: https://www.redhat.com/archives/libguestfs/2019-November/msg00209.html In v4: - Rebase on top of current master. Includes various fixes and updates required because of Nir's patches that went into master. - Fix api_version() -> API_VERSION in patch 2 noted previously on the mailing list. Rich.
Richard W.M. Jones
2019-Nov-25 10:03 UTC
[Libguestfs] [PATCH nbdkit v4 1/7] python: Add various constants to the API.
These are accessible from the plugin by:
import nbdkit
if flags & nbdkit.FLAG_MAY_TRIM:
&c.
Many (all?) of these are not yet useful for plugins, some will never
be useful, but they only consume a tiny bit of memory and it's nice to
have the complete set available for future use.
---
plugins/python/python.c | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)
diff --git a/plugins/python/python.c b/plugins/python/python.c
index 2b4361a..ff96e0b 100644
--- a/plugins/python/python.c
+++ b/plugins/python/python.c
@@ -231,6 +231,36 @@ create_nbdkit_module (void)
nbdkit_error ("could not create the nbdkit API module");
exit (EXIT_FAILURE);
}
+
+ /* Constants corresponding to various flags. */
+#define ADD_INT_CONSTANT(name) \
+ if (PyModule_AddIntConstant (m, #name, NBDKIT_##name) == -1) { \
+ nbdkit_error ("could not add constant %s to nbdkit API module", \
+ #name); \
+ exit (EXIT_FAILURE); \
+ }
+ ADD_INT_CONSTANT (THREAD_MODEL_SERIALIZE_CONNECTIONS);
+ ADD_INT_CONSTANT (THREAD_MODEL_SERIALIZE_ALL_REQUESTS);
+ ADD_INT_CONSTANT (THREAD_MODEL_SERIALIZE_REQUESTS);
+ ADD_INT_CONSTANT (THREAD_MODEL_PARALLEL);
+
+ ADD_INT_CONSTANT (FLAG_MAY_TRIM);
+ ADD_INT_CONSTANT (FLAG_FUA);
+ ADD_INT_CONSTANT (FLAG_REQ_ONE);
+ ADD_INT_CONSTANT (FLAG_FAST_ZERO);
+
+ ADD_INT_CONSTANT (FUA_NONE);
+ ADD_INT_CONSTANT (FUA_EMULATE);
+ ADD_INT_CONSTANT (FUA_NATIVE);
+
+ ADD_INT_CONSTANT (CACHE_NONE);
+ ADD_INT_CONSTANT (CACHE_EMULATE);
+ ADD_INT_CONSTANT (CACHE_NATIVE);
+
+ ADD_INT_CONSTANT (EXTENT_HOLE);
+ ADD_INT_CONSTANT (EXTENT_ZERO);
+#undef ADD_INT_CONSTANT
+
return m;
}
--
2.23.0
Richard W.M. Jones
2019-Nov-25 10:03 UTC
[Libguestfs] [PATCH nbdkit v4 2/7] python: Implement nbdkit API version 2.
To avoid breaking existing plugins, Python plugins wishing to use
version 2 of the API must opt in by declaring:
API_VERSION = 2
(Plugins which do not do this are assumed to want API version 1).
---
plugins/python/example.py | 14 ++-
plugins/python/nbdkit-python-plugin.pod | 59 ++++++++-----
plugins/python/python.c | 110 +++++++++++++++++++++---
tests/test.py | 19 ++--
4 files changed, 155 insertions(+), 47 deletions(-)
diff --git a/plugins/python/example.py b/plugins/python/example.py
index 60f9d7f..c85d2f8 100644
--- a/plugins/python/example.py
+++ b/plugins/python/example.py
@@ -34,6 +34,12 @@ import errno
disk = bytearray(1024 * 1024)
+# There are several variants of the API. nbdkit will call this
+# function first to determine which one you want to use. This is the
+# latest version at the time this example was written.
+API_VERSION = 2
+
+
# This just prints the extra command line parameters, but real plugins
# should parse them and reject any unknown parameters.
def config(key, value):
@@ -54,20 +60,20 @@ def get_size(h):
return len(disk)
-def pread(h, count, offset):
+def pread(h, count, offset, flags):
global disk
return disk[offset:offset+count]
-def pwrite(h, buf, offset):
+def pwrite(h, buf, offset, flags):
global disk
end = offset + len(buf)
disk[offset:end] = buf
-def zero(h, count, offset, may_trim):
+def zero(h, count, offset, flags):
global disk
- if may_trim:
+ if flags & nbdkit.FLAG_MAY_TRIM:
disk[offset:offset+count] = bytearray(count)
else:
nbdkit.set_error(errno.EOPNOTSUPP)
diff --git a/plugins/python/nbdkit-python-plugin.pod
b/plugins/python/nbdkit-python-plugin.pod
index 3680fd6..fe2a542 100644
--- a/plugins/python/nbdkit-python-plugin.pod
+++ b/plugins/python/nbdkit-python-plugin.pod
@@ -33,11 +33,12 @@ To write a Python nbdkit plugin, you create a Python file
which
contains at least the following required functions (in the top level
C<__main__> module):
+ API_VERSION = 2
def open(readonly):
# see below
def get_size(h):
# see below
- def pread(h, count, offset):
+ def pread(h, count, offset, flags):
# see below
Note that the subroutines must have those literal names (like C<open>),
@@ -82,6 +83,18 @@ I<--dump-plugin> option, eg:
python_version=3.7.0
python_pep_384_abi_version=3
+=head2 API versions
+
+The nbdkit API has evolved and new versions are released periodically.
+To ensure backwards compatibility plugins have to opt in to the new
+version. From Python you do this by declaring a constant in your
+module:
+
+ API_VERSION = 2
+
+(where 2 is the latest version at the time this documentation was
+written). All newly written Python modules must have this constant.
+
=head2 Executable script
If you want you can make the script executable and include a
"shebang"
@@ -199,12 +212,12 @@ contents will be garbage collected.
(Required)
- def pread(h, count, offset):
+ def pread(h, count, offset, flags):
# construct a buffer of length count bytes and return it
The body of your C<pread> function should construct a buffer of length
(at least) C<count> bytes. You should read C<count> bytes from the
-disk starting at C<offset>.
+disk starting at C<offset>. C<flags> is always 0.
The returned buffer can be any type compatible with the Python 3
buffer protocol, such as bytearray, bytes or memoryview
@@ -219,13 +232,13 @@ C<nbdkit.set_error> first.
(Optional)
- def pwrite(h, buf, offset):
+ def pwrite(h, buf, offset, flags):
length = len (buf)
# no return value
The body of your C<pwrite> function should write the buffer C<buf>
to
the disk. You should write C<count> bytes to the disk starting at
-C<offset>.
+C<offset>. C<flags> may contain C<nbdkit.FLAG_FUA>.
NBD only supports whole writes, so your function should try to
write the whole region (perhaps requiring a loop). If the write
@@ -236,11 +249,12 @@ fails or is partial, your function should throw an
exception,
(Optional)
- def flush(h):
+ def flush(h, flags):
# no return value
The body of your C<flush> function should do a L<sync(2)> or
L<fdatasync(2)> or equivalent on the backing store.
+C<flags> is always 0.
If the flush fails, your function should throw an exception, optionally
using C<nbdkit.set_error> first.
@@ -249,32 +263,35 @@ using C<nbdkit.set_error> first.
(Optional)
- def trim(h, count, offset):
+ def trim(h, count, offset, flags):
# no return value
-The body of your C<trim> function should "punch a hole" in the
-backing store. If the trim fails, your function should throw an
-exception, optionally using C<nbdkit.set_error> first.
+The body of your C<trim> function should "punch a hole" in the
backing
+store. C<flags> may contain C<nbdkit.FLAG_FUA>. If the trim
fails,
+your function should throw an exception, optionally using
+C<nbdkit.set_error> first.
=item C<zero>
(Optional)
- def zero(h, count, offset, may_trim):
+ def zero(h, count, offset, flags):
# no return value
-The body of your C<zero> function should ensure that C<count> bytes
-of the disk, starting at C<offset>, will read back as zero. If
-C<may_trim> is true, the operation may be optimized as a trim as long
-as subsequent reads see zeroes.
+The body of your C<zero> function should ensure that C<count> bytes
of
+the disk, starting at C<offset>, will read back as zero. C<flags>
is
+a bitmask which may include C<nbdkit.FLAG_MAY_TRIM>,
+C<nbdkit.FLAG_FUA>, C<nbdkit.FLAG_FAST_ZERO>.
NBD only supports whole writes, so your function should try to
-write the whole region (perhaps requiring a loop). If the write
-fails or is partial, your function should throw an exception,
-optionally using C<nbdkit.set_error> first. In particular, if
-you would like to automatically fall back to C<pwrite> (perhaps
-because there is nothing to optimize if C<may_trim> is false),
-use C<nbdkit.set_error(errno.EOPNOTSUPP)>.
+write the whole region (perhaps requiring a loop).
+
+If the write fails or is partial, your function should throw an
+exception, optionally using C<nbdkit.set_error> first. In particular,
+if you would like to automatically fall back to C<pwrite> (perhaps
+because there is nothing to optimize if
+S<C<flags & nbdkit.FLAG_MAY_TRIM>> is false), use
+S<C<nbdkit.set_error (errno.EOPNOTSUPP)>>.
=back
diff --git a/plugins/python/python.c b/plugins/python/python.c
index ff96e0b..68d01e8 100644
--- a/plugins/python/python.c
+++ b/plugins/python/python.c
@@ -46,6 +46,8 @@
#define PY_SSIZE_T_CLEAN 1
#include <Python.h>
+#define NBDKIT_API_VERSION 2
+
#include <nbdkit-plugin.h>
#include "cleanup.h"
@@ -60,6 +62,7 @@
*/
static const char *script;
static PyObject *module;
+static int py_api_version = 1;
static int last_error;
@@ -285,9 +288,14 @@ py_dump_plugin (void)
PyObject *fn;
PyObject *r;
+ /* Python version and ABI. */
printf ("python_version=%s\n", PY_VERSION);
printf ("python_pep_384_abi_version=%d\n", PYTHON_ABI_VERSION);
+ /* Maximum nbdkit API version supported. */
+ printf ("nbdkit_python_maximum_api_version=%d\n",
NBDKIT_API_VERSION);
+
+ /* If the script has a dump_plugin function, call it. */
if (script && callback_defined ("dump_plugin", &fn)) {
PyErr_Clear ();
@@ -297,6 +305,30 @@ py_dump_plugin (void)
}
}
+static int
+get_py_api_version (void)
+{
+ PyObject *obj;
+ long value;
+
+ obj = PyObject_GetAttrString (module, "API_VERSION");
+ if (obj == NULL)
+ return 1; /* Default to API version 1. */
+
+ value = PyLong_AsLong (obj);
+ Py_DECREF (obj);
+
+ if (value < 1 || value > NBDKIT_API_VERSION) {
+ nbdkit_error ("%s: API_VERSION requested unknown version: %ld. "
+ "This plugin supports API versions between 1 and
%d.",
+ script, value, NBDKIT_API_VERSION);
+ return -1;
+ }
+
+ nbdkit_debug ("module requested API_VERSION %ld", value);
+ return (int) value;
+}
+
static int
py_config (const char *key, const char *value)
{
@@ -359,6 +391,11 @@ py_config (const char *key, const char *value)
"nbdkit requires these callbacks.", script);
return -1;
}
+
+ /* Get the API version. */
+ py_api_version = get_py_api_version ();
+ if (py_api_version == -1)
+ return -1;
}
else if (callback_defined ("config", &fn)) {
/* Other parameters are passed to the Python .config callback. */
@@ -469,8 +506,8 @@ py_get_size (void *handle)
}
static int
-py_pread (void *handle, void *buf,
- uint32_t count, uint64_t offset)
+py_pread (void *handle, void *buf, uint32_t count, uint64_t offset,
+ uint32_t flags)
{
PyObject *obj = handle;
PyObject *fn;
@@ -485,7 +522,15 @@ py_pread (void *handle, void *buf,
PyErr_Clear ();
- r = PyObject_CallFunction (fn, "OiL", obj, count, offset, NULL);
+ switch (py_api_version) {
+ case 1:
+ r = PyObject_CallFunction (fn, "OiL", obj, count, offset, NULL);
+ break;
+ case 2:
+ r = PyObject_CallFunction (fn, "OiLI", obj, count, offset, flags,
NULL);
+ break;
+ default: abort ();
+ }
Py_DECREF (fn);
if (check_python_failure ("pread") == -1)
return ret;
@@ -515,8 +560,8 @@ out:
}
static int
-py_pwrite (void *handle, const void *buf,
- uint32_t count, uint64_t offset)
+py_pwrite (void *handle, const void *buf, uint32_t count, uint64_t offset,
+ uint32_t flags)
{
PyObject *obj = handle;
PyObject *fn;
@@ -525,9 +570,19 @@ py_pwrite (void *handle, const void *buf,
if (callback_defined ("pwrite", &fn)) {
PyErr_Clear ();
- r = PyObject_CallFunction (fn, "ONL", obj,
+ switch (py_api_version) {
+ case 1:
+ r = PyObject_CallFunction (fn, "ONL", obj,
PyMemoryView_FromMemory ((char *)buf, count, PyBUF_READ),
offset, NULL);
+ break;
+ case 2:
+ r = PyObject_CallFunction (fn, "ONLI", obj,
+ PyMemoryView_FromMemory ((char *)buf, count, PyBUF_READ),
+ offset, flags, NULL);
+ break;
+ default: abort ();
+ }
Py_DECREF (fn);
if (check_python_failure ("pwrite") == -1)
return -1;
@@ -542,7 +597,7 @@ py_pwrite (void *handle, const void *buf,
}
static int
-py_flush (void *handle)
+py_flush (void *handle, uint32_t flags)
{
PyObject *obj = handle;
PyObject *fn;
@@ -551,7 +606,15 @@ py_flush (void *handle)
if (callback_defined ("flush", &fn)) {
PyErr_Clear ();
- r = PyObject_CallFunctionObjArgs (fn, obj, NULL);
+ switch (py_api_version) {
+ case 1:
+ r = PyObject_CallFunctionObjArgs (fn, obj, NULL);
+ break;
+ case 2:
+ r = PyObject_CallFunction (fn, "OI", obj, flags, NULL);
+ break;
+ default: abort ();
+ }
Py_DECREF (fn);
if (check_python_failure ("flush") == -1)
return -1;
@@ -566,7 +629,7 @@ py_flush (void *handle)
}
static int
-py_trim (void *handle, uint32_t count, uint64_t offset)
+py_trim (void *handle, uint32_t count, uint64_t offset, uint32_t flags)
{
PyObject *obj = handle;
PyObject *fn;
@@ -575,7 +638,15 @@ py_trim (void *handle, uint32_t count, uint64_t offset)
if (callback_defined ("trim", &fn)) {
PyErr_Clear ();
- r = PyObject_CallFunction (fn, "OiL", obj, count, offset, NULL);
+ switch (py_api_version) {
+ case 1:
+ r = PyObject_CallFunction (fn, "OiL", obj, count, offset,
NULL);
+ break;
+ case 2:
+ r = PyObject_CallFunction (fn, "OiLI", obj, count, offset,
flags, NULL);
+ break;
+ default: abort ();
+ }
Py_DECREF (fn);
if (check_python_failure ("trim") == -1)
return -1;
@@ -590,7 +661,7 @@ py_trim (void *handle, uint32_t count, uint64_t offset)
}
static int
-py_zero (void *handle, uint32_t count, uint64_t offset, int may_trim)
+py_zero (void *handle, uint32_t count, uint64_t offset, uint32_t flags)
{
PyObject *obj = handle;
PyObject *fn;
@@ -600,9 +671,20 @@ py_zero (void *handle, uint32_t count, uint64_t offset, int
may_trim)
PyErr_Clear ();
last_error = 0;
- r = PyObject_CallFunction (fn, "OiLO",
- obj, count, offset,
- may_trim ? Py_True : Py_False, NULL);
+ switch (py_api_version) {
+ case 1: {
+ int may_trim = flags & NBDKIT_FLAG_MAY_TRIM;
+ r = PyObject_CallFunction (fn, "OiLO",
+ obj, count, offset,
+ may_trim ? Py_True : Py_False, NULL);
+ break;
+ }
+ case 2:
+ r = PyObject_CallFunction (fn, "OiLI",
+ obj, count, offset, flags, NULL);
+ break;
+ default: abort ();
+ }
Py_DECREF (fn);
if (last_error == EOPNOTSUPP || last_error == ENOTSUP) {
/* When user requests this particular error, we want to
diff --git a/tests/test.py b/tests/test.py
index 9a2e947..bc05a0b 100644
--- a/tests/test.py
+++ b/tests/test.py
@@ -3,6 +3,9 @@ import nbdkit
disk = bytearray(1024*1024)
+API_VERSION = 2
+
+
def config_complete():
print ("set_error = %r" % nbdkit.set_error)
@@ -32,25 +35,25 @@ def can_trim(h):
return True
-def pread(h, count, offset):
+def pread(h, count, offset, flags):
global disk
return disk[offset:offset+count]
-def pwrite(h, buf, offset):
+def pwrite(h, buf, offset, flags):
global disk
end = offset + len(buf)
disk[offset:end] = buf
-def zero(h, count, offset, may_trim=False):
- global disk
- disk[offset:offset+count] = bytearray(count)
+def flush(h, flags):
+ pass
-def flush(h):
+def trim(h, count, offset, flags):
pass
-def trim(h, count, offset):
- pass
+def zero(h, count, offset, flags):
+ global disk
+ disk[offset:offset+count] = bytearray(count)
--
2.23.0
Richard W.M. Jones
2019-Nov-25 10:03 UTC
[Libguestfs] [PATCH nbdkit v4 3/7] python: Implement cache.
However this does not implement can_cache, since that is not a simple
boolean.
---
plugins/python/nbdkit-python-plugin.pod | 14 ++++++++++-
plugins/python/python.c | 31 +++++++++++++++++++++++++
2 files changed, 44 insertions(+), 1 deletion(-)
diff --git a/plugins/python/nbdkit-python-plugin.pod
b/plugins/python/nbdkit-python-plugin.pod
index fe2a542..ebea0a7 100644
--- a/plugins/python/nbdkit-python-plugin.pod
+++ b/plugins/python/nbdkit-python-plugin.pod
@@ -293,6 +293,19 @@ because there is nothing to optimize if
S<C<flags & nbdkit.FLAG_MAY_TRIM>> is false), use
S<C<nbdkit.set_error (errno.EOPNOTSUPP)>>.
+=item C<cache>
+
+(Optional)
+
+ def cache(h, count, offset, flags):
+ # no return value
+
+The body of your C<cache> function should prefetch data in the
+indicated range.
+
+If the cache operation fails, your function should throw an exception,
+optionally using C<nbdkit.set_error> first.
+
=back
=head2 Missing callbacks
@@ -321,7 +334,6 @@ C<can_zero>,
C<can_fast_zero>,
C<can_extents>,
C<can_multi_conn>,
-C<cache>,
C<extents>.
These are not yet supported.
diff --git a/plugins/python/python.c b/plugins/python/python.c
index 68d01e8..5b0d0f5 100644
--- a/plugins/python/python.c
+++ b/plugins/python/python.c
@@ -707,6 +707,36 @@ py_zero (void *handle, uint32_t count, uint64_t offset,
uint32_t flags)
return -1;
}
+static int
+py_cache (void *handle, uint32_t count, uint64_t offset, uint32_t flags)
+{
+ PyObject *obj = handle;
+ PyObject *fn;
+ PyObject *r;
+
+ if (callback_defined ("cache", &fn)) {
+ PyErr_Clear ();
+
+ switch (py_api_version) {
+ case 1:
+ case 2:
+ r = PyObject_CallFunction (fn, "OiLI", obj, count, offset,
flags, NULL);
+ break;
+ default: abort ();
+ }
+ Py_DECREF (fn);
+ if (check_python_failure ("cache") == -1)
+ return -1;
+ Py_DECREF (r);
+ }
+ else {
+ nbdkit_error ("%s not implemented", "cache");
+ return -1;
+ }
+
+ return 0;
+}
+
static int
boolean_callback (void *handle, const char *can_fn, const char *plain_fn)
{
@@ -792,6 +822,7 @@ static struct nbdkit_plugin plugin = {
.flush = py_flush,
.trim = py_trim,
.zero = py_zero,
+ .cache = py_cache,
};
NBDKIT_REGISTER_PLUGIN (plugin)
--
2.23.0
Richard W.M. Jones
2019-Nov-25 10:03 UTC
[Libguestfs] [PATCH nbdkit v4 4/7] python: Implement can_zero, can_fast_zero.
---
plugins/python/nbdkit-python-plugin.pod | 16 ++++++++++++++--
plugins/python/python.c | 14 ++++++++++++++
2 files changed, 28 insertions(+), 2 deletions(-)
diff --git a/plugins/python/nbdkit-python-plugin.pod
b/plugins/python/nbdkit-python-plugin.pod
index ebea0a7..0def7bb 100644
--- a/plugins/python/nbdkit-python-plugin.pod
+++ b/plugins/python/nbdkit-python-plugin.pod
@@ -208,6 +208,20 @@ contents will be garbage collected.
def can_trim(h):
# return a boolean
+=item C<can_zero>
+
+(Optional)
+
+ def can_zero(h):
+ # return a boolean
+
+=item C<can_fast_zero>
+
+(Optional)
+
+ def can_fast_zero(h):
+ # return a boolean
+
=item C<pread>
(Required)
@@ -330,8 +344,6 @@ C<config_help>,
C<magic_config_key>,
C<can_fua>,
C<can_cache>,
-C<can_zero>,
-C<can_fast_zero>,
C<can_extents>,
C<can_multi_conn>,
C<extents>.
diff --git a/plugins/python/python.c b/plugins/python/python.c
index 5b0d0f5..01bd285 100644
--- a/plugins/python/python.c
+++ b/plugins/python/python.c
@@ -790,6 +790,18 @@ py_can_trim (void *handle)
return boolean_callback (handle, "can_trim", "trim");
}
+static int
+py_can_zero (void *handle)
+{
+ return boolean_callback (handle, "can_zero", "zero");
+}
+
+static int
+py_can_fast_zero (void *handle)
+{
+ return boolean_callback (handle, "can_fast_zero", NULL);
+}
+
#define py_config_help \
"script=<FILENAME> (required) The Python plugin to
run.\n" \
"[other arguments may be used by the plugin that you load]"
@@ -816,6 +828,8 @@ static struct nbdkit_plugin plugin = {
.can_write = py_can_write,
.can_flush = py_can_flush,
.can_trim = py_can_trim,
+ .can_zero = py_can_zero,
+ .can_fast_zero = py_can_fast_zero,
.pread = py_pread,
.pwrite = py_pwrite,
--
2.23.0
Richard W.M. Jones
2019-Nov-25 10:03 UTC
[Libguestfs] [PATCH nbdkit v4 5/7] python: Implement can_multi_conn.
---
plugins/python/nbdkit-python-plugin.pod | 8 +++++++-
plugins/python/python.c | 7 +++++++
2 files changed, 14 insertions(+), 1 deletion(-)
diff --git a/plugins/python/nbdkit-python-plugin.pod
b/plugins/python/nbdkit-python-plugin.pod
index 0def7bb..a0b4d90 100644
--- a/plugins/python/nbdkit-python-plugin.pod
+++ b/plugins/python/nbdkit-python-plugin.pod
@@ -187,6 +187,13 @@ contents will be garbage collected.
def is_rotational(h):
# return a boolean
+=item C<can_multi_conn>
+
+(Optional)
+
+ def can_multi_conn(h):
+ # return a boolean
+
=item C<can_write>
(Optional)
@@ -345,7 +352,6 @@ C<magic_config_key>,
C<can_fua>,
C<can_cache>,
C<can_extents>,
-C<can_multi_conn>,
C<extents>.
These are not yet supported.
diff --git a/plugins/python/python.c b/plugins/python/python.c
index 01bd285..12f45f7 100644
--- a/plugins/python/python.c
+++ b/plugins/python/python.c
@@ -772,6 +772,12 @@ py_is_rotational (void *handle)
return boolean_callback (handle, "is_rotational", NULL);
}
+static int
+py_can_multi_conn (void *handle)
+{
+ return boolean_callback (handle, "can_multi_conn", NULL);
+}
+
static int
py_can_write (void *handle)
{
@@ -825,6 +831,7 @@ static struct nbdkit_plugin plugin = {
.get_size = py_get_size,
.is_rotational = py_is_rotational,
+ .can_multi_conn = py_can_multi_conn,
.can_write = py_can_write,
.can_flush = py_can_flush,
.can_trim = py_can_trim,
--
2.23.0
Richard W.M. Jones
2019-Nov-25 10:03 UTC
[Libguestfs] [PATCH nbdkit v4 6/7] python: Implement can_fua and can_cache.
---
plugins/python/nbdkit-python-plugin.pod | 18 +++++++-
plugins/python/python.c | 58 +++++++++++++++++++++++++
2 files changed, 74 insertions(+), 2 deletions(-)
diff --git a/plugins/python/nbdkit-python-plugin.pod
b/plugins/python/nbdkit-python-plugin.pod
index a0b4d90..0b31ebc 100644
--- a/plugins/python/nbdkit-python-plugin.pod
+++ b/plugins/python/nbdkit-python-plugin.pod
@@ -229,6 +229,22 @@ contents will be garbage collected.
def can_fast_zero(h):
# return a boolean
+=item C<can_fua>
+
+(Optional)
+
+ def can_fua(h):
+ # return nbdkit.FUA_NONE or nbdkit.FUA_EMULATE
+ # or nbdkit.FUA_NATIVE
+
+=item C<can_cache>
+
+(Optional)
+
+ def can_cache(h):
+ # return nbdkit.CACHE_NONE or nbdkit.CACHE_EMULATE
+ # or nbdkit.CACHE_NATIVE
+
=item C<pread>
(Required)
@@ -349,8 +365,6 @@ C<longname>,
C<description>,
C<config_help>,
C<magic_config_key>,
-C<can_fua>,
-C<can_cache>,
C<can_extents>,
C<extents>.
diff --git a/plugins/python/python.c b/plugins/python/python.c
index 12f45f7..252ca37 100644
--- a/plugins/python/python.c
+++ b/plugins/python/python.c
@@ -808,6 +808,62 @@ py_can_fast_zero (void *handle)
return boolean_callback (handle, "can_fast_zero", NULL);
}
+static int
+py_can_fua (void *handle)
+{
+ PyObject *obj = handle;
+ PyObject *fn;
+ PyObject *r;
+ int ret;
+
+ if (callback_defined ("can_fua", &fn)) {
+ PyErr_Clear ();
+
+ r = PyObject_CallFunctionObjArgs (fn, obj, NULL);
+ Py_DECREF (fn);
+ if (check_python_failure ("can_fua") == -1)
+ return -1;
+ ret = PyLong_AsLong (r);
+ Py_DECREF (r);
+ return ret;
+ }
+ /* No Python ‘can_fua’, but check if there's a Python ‘flush’
+ * callback defined. (In C modules, nbdkit would do this).
+ */
+ else if (callback_defined ("flush", NULL))
+ return NBDKIT_FUA_EMULATE;
+ else
+ return NBDKIT_FUA_NONE;
+}
+
+static int
+py_can_cache (void *handle)
+{
+ PyObject *obj = handle;
+ PyObject *fn;
+ PyObject *r;
+ int ret;
+
+ if (callback_defined ("can_cache", &fn)) {
+ PyErr_Clear ();
+
+ r = PyObject_CallFunctionObjArgs (fn, obj, NULL);
+ Py_DECREF (fn);
+ if (check_python_failure ("can_cache") == -1)
+ return -1;
+ ret = PyLong_AsLong (r);
+ Py_DECREF (r);
+ return ret;
+ }
+ /* No Python ‘can_cache’, but check if there's a Python ‘cache’
+ * callback defined. (In C modules, nbdkit would do this).
+ */
+ else if (callback_defined ("cache", NULL))
+ return NBDKIT_CACHE_NATIVE;
+ else
+ return NBDKIT_CACHE_NONE;
+}
+
#define py_config_help \
"script=<FILENAME> (required) The Python plugin to
run.\n" \
"[other arguments may be used by the plugin that you load]"
@@ -837,6 +893,8 @@ static struct nbdkit_plugin plugin = {
.can_trim = py_can_trim,
.can_zero = py_can_zero,
.can_fast_zero = py_can_fast_zero,
+ .can_fua = py_can_fua,
+ .can_cache = py_can_cache,
.pread = py_pread,
.pwrite = py_pwrite,
--
2.23.0
Richard W.M. Jones
2019-Nov-25 10:03 UTC
[Libguestfs] [PATCH nbdkit v4 7/7] tests: Test the Python plugin thoroughly.
This tests the Python plugin thoroughly by issuing client commands
through libnbd and checking we get the expected results.
---
.gitignore | 1 +
README | 2 +
tests/Makefile.am | 15 +--
tests/test-lang-plugins.c | 3 +-
tests/test-python-plugin.py | 139 +++++++++++++++++++++
tests/test-python.sh | 49 ++++++++
tests/test.py | 59 ---------
tests/test_python.py | 236 ++++++++++++++++++++++++++++++++++++
8 files changed, 433 insertions(+), 71 deletions(-)
diff --git a/.gitignore b/.gitignore
index b25ac7f..e25bd99 100644
--- a/.gitignore
+++ b/.gitignore
@@ -71,6 +71,7 @@ Makefile.in
/server/synopsis.c
/server/test-public
/stamp-h1
+/tests/__pycache__/
/tests/disk
/tests/disk.gz
/tests/disk.xz
diff --git a/README b/README
index 7034fd8..9313f8a 100644
--- a/README
+++ b/README
@@ -130,6 +130,8 @@ For the Python plugin:
- python development libraries
+ - python unittest to run the test suite
+
For the OCaml plugin:
- OCaml >= 4.02.2
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 13cd8f3..848cc07 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -115,7 +115,9 @@ EXTRA_DIST = \
test-pattern-largest-for-qemu.sh \
test-python-exception.sh \
test.pl \
- test.py \
+ test_python.py \
+ test-python-plugin.py \
+ test-python.sh \
test-rate.sh \
test-rate-dynamic.sh \
test.rb \
@@ -207,6 +209,7 @@ EXTRA_PROGRAMS TESTS_ENVIRONMENT = \
PATH=$(abs_top_builddir):$(PATH) \
SRCDIR=$(srcdir) \
+ PYTHON=$(PYTHON) \
LIBGUESTFS_ATTACH_METHOD=appliance \
LIBGUESTFS_DEBUG=1 \
LIBGUESTFS_TRACE=1 \
@@ -787,18 +790,10 @@ endif HAVE_PERL
if HAVE_PYTHON
TESTS += \
+ test-python.sh \
test-python-exception.sh \
test-shebang-python.sh \
$(NULL)
-LIBGUESTFS_TESTS += test-python
-
-test_python_SOURCES = test-lang-plugins.c test.h
-test_python_CFLAGS = \
- -DLANG='"python"'
-DSCRIPT='"$(srcdir)/test.py"' \
- $(WARNINGS_CFLAGS) \
- $(LIBGUESTFS_CFLAGS) \
- $(NULL)
-test_python_LDADD = libtest.la $(LIBGUESTFS_LIBS)
endif HAVE_PYTHON
diff --git a/tests/test-lang-plugins.c b/tests/test-lang-plugins.c
index ffb1918..93f9938 100644
--- a/tests/test-lang-plugins.c
+++ b/tests/test-lang-plugins.c
@@ -56,8 +56,7 @@ main (int argc, char *argv[])
*/
s = getenv ("NBDKIT_VALGRIND");
if (s && strcmp (s, "1") == 0 &&
- (strcmp (LANG, "python") == 0 ||
- strcmp (LANG, "ruby") == 0 ||
+ (strcmp (LANG, "ruby") == 0 ||
strcmp (LANG, "tcl") == 0)) {
fprintf (stderr, "%s test skipped under valgrind.\n", LANG);
exit (77); /* Tells automake to skip the test. */
diff --git a/tests/test-python-plugin.py b/tests/test-python-plugin.py
new file mode 100644
index 0000000..d7335bd
--- /dev/null
+++ b/tests/test-python-plugin.py
@@ -0,0 +1,139 @@
+# nbdkit test plugin
+# Copyright (C) 2019 Red Hat Inc.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+# * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#
+# * Redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution.
+#
+# * Neither the name of Red Hat nor the names of its contributors may be
+# used to endorse or promote products derived from this software without
+# specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS
IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+# PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR
+# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+# USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+# OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+
+"""See test-python.py."""
+
+import nbdkit
+import sys
+import pickle
+import base64
+
+API_VERSION = 2
+
+cfg = {}
+
+def config (k, v):
+ global cfg
+ if k == "cfg":
+ cfg = pickle.loads (base64.b64decode (v.encode()))
+
+def config_complete ():
+ print ("set_error = %r" % nbdkit.set_error)
+
+def open (readonly):
+ return {
+ 'disk': bytearray (cfg.get ('size', 0))
+ }
+
+def get_size (h):
+ return len (h['disk'])
+
+def is_rotational (h):
+ return cfg.get ('is_rotational', False)
+
+def can_multi_conn (h):
+ return cfg.get ('can_multi_conn', False)
+
+def can_write (h):
+ return cfg.get ('can_write', True)
+
+def can_flush (h):
+ return cfg.get ('can_flush', False)
+
+def can_trim (h):
+ return cfg.get ('can_trim', False)
+
+def can_zero (h):
+ return cfg.get ('can_zero', False)
+
+def can_fast_zero (h):
+ return cfg.get ('can_fast_zero', False)
+
+def can_fua (h):
+ fua = cfg.get ('can_fua', "none")
+ if fua == "none":
+ return nbdkit.FUA_NONE
+ elif fua == "emulate":
+ return nbdkit.FUA_EMULATE
+ elif fua == "native":
+ return nbdkit.FUA_NATIVE
+
+def can_cache (h):
+ cache = cfg.get ('can_cache', "none")
+ if cache == "none":
+ return nbdkit.CACHE_NONE
+ elif cache == "emulate":
+ return nbdkit.CACHE_EMULATE
+ elif cache == "native":
+ return nbdkit.CACHE_NATIVE
+
+def pread (h, count, offset, flags):
+ assert flags == 0
+ pread_result = cfg.get ('pread_result', "bytearray")
+ b = h['disk'][offset:offset+count]
+ if pread_result == "bytearray":
+ return b
+ elif pread_result == "bytes":
+ return bytes (b)
+ elif pread_result == "memoryview":
+ return memoryview (b)
+
+def pwrite (h, buf, offset, flags):
+ expect_fua = cfg.get ('pwrite_expect_fua', False)
+ actual_fua = bool (flags & nbdkit.FLAG_FUA)
+ assert expect_fua == actual_fua
+ end = offset + len(buf)
+ h['disk'][offset:end] = buf
+
+def flush (h, flags):
+ assert flags == 0
+
+def trim (h, count, offset, flags):
+ expect_fua = cfg.get ('trim_expect_fua', False)
+ actual_fua = bool (flags & nbdkit.FLAG_FUA)
+ assert expect_fua == actual_fua
+ h['disk'][offset:offset+count] = bytearray(count)
+
+def zero (h, count, offset, flags):
+ expect_fua = cfg.get ('zero_expect_fua', False)
+ actual_fua = bool (flags & nbdkit.FLAG_FUA)
+ assert expect_fua == actual_fua
+ expect_may_trim = cfg.get ('zero_expect_may_trim', False)
+ actual_may_trim = bool (flags & nbdkit.FLAG_MAY_TRIM)
+ assert expect_may_trim == actual_may_trim
+ expect_fast_zero = cfg.get ('zero_expect_fast_zero', False)
+ actual_fast_zero = bool (flags & nbdkit.FLAG_FAST_ZERO)
+ assert expect_fast_zero == actual_fast_zero
+ h['disk'][offset:offset+count] = bytearray(count)
+
+def cache (h, count, offset, flags):
+ assert flags == 0
+ # do nothing
diff --git a/tests/test-python.sh b/tests/test-python.sh
new file mode 100755
index 0000000..50324d0
--- /dev/null
+++ b/tests/test-python.sh
@@ -0,0 +1,49 @@
+#!/usr/bin/env bash
+# nbdkit
+# Copyright (C) 2019 Red Hat Inc.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+# * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#
+# * Redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution.
+#
+# * Neither the name of Red Hat nor the names of its contributors may be
+# used to endorse or promote products derived from this software without
+# specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS
IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+# PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR
+# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+# USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+# OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+
+source ./functions.sh
+set -e
+set -x
+
+requires $PYTHON --version
+requires $PYTHON -c 'import unittest'
+requires $PYTHON -c 'import nbd'
+requires test -f test_python.py
+requires test -f test-python-plugin.py
+
+# Python has proven very difficult to valgrind, therefore it is disabled.
+if [ "$NBDKIT_VALGRIND" = "1" ]; then
+ echo "$0: skipping Python test under valgrind."
+ exit 77
+fi
+
+$PYTHON -m unittest test_python
diff --git a/tests/test.py b/tests/test.py
deleted file mode 100644
index bc05a0b..0000000
--- a/tests/test.py
+++ /dev/null
@@ -1,59 +0,0 @@
-import nbdkit
-
-disk = bytearray(1024*1024)
-
-
-API_VERSION = 2
-
-
-def config_complete():
- print ("set_error = %r" % nbdkit.set_error)
-
-
-def open(readonly):
- return 1
-
-
-def get_size(h):
- global disk
- return len(disk)
-
-
-def can_write(h):
- return True
-
-
-def can_flush(h):
- return True
-
-
-def is_rotational(h):
- return False
-
-
-def can_trim(h):
- return True
-
-
-def pread(h, count, offset, flags):
- global disk
- return disk[offset:offset+count]
-
-
-def pwrite(h, buf, offset, flags):
- global disk
- end = offset + len(buf)
- disk[offset:end] = buf
-
-
-def flush(h, flags):
- pass
-
-
-def trim(h, count, offset, flags):
- pass
-
-
-def zero(h, count, offset, flags):
- global disk
- disk[offset:offset+count] = bytearray(count)
diff --git a/tests/test_python.py b/tests/test_python.py
new file mode 100755
index 0000000..b2c60f0
--- /dev/null
+++ b/tests/test_python.py
@@ -0,0 +1,236 @@
+#!/usr/bin/env python3
+# nbdkit
+# Copyright (C) 2019 Red Hat Inc.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+# * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#
+# * Redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution.
+#
+# * Neither the name of Red Hat nor the names of its contributors may be
+# used to endorse or promote products derived from this software without
+# specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS
IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+# PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR
+# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+# USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+# OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+
+"""
+This tests the Python plugin thoroughly by issuing client commands
+through libnbd and checking we get the expected results. It uses an
+associated plugin (test-python-plugin.sh).
+"""
+
+import os
+import sys
+import nbd
+import unittest
+import pickle
+import base64
+
+class Test (unittest.TestCase):
+ def setUp (self):
+ self.h = nbd.NBD ()
+
+ def tearDown (self):
+ del self.h
+
+ def connect (self, cfg):
+ cfg = base64.b64encode (pickle.dumps (cfg)).decode()
+ cmd = ["nbdkit", "-v", "-s",
"--exit-with-parent",
+ "python", "test-python-plugin.py",
"cfg=" + cfg]
+ self.h.connect_command (cmd)
+
+ def test_none (self):
+ """
+ Test we can send an empty pickled test configuration and do
+ nothing else. This is just to ensure the machinery of the
+ test works.
+ """
+ self.connect ({})
+
+ def test_size_512 (self):
+ """Test the size."""
+ self.connect ({"size": 512})
+ assert self.h.get_size() == 512
+
+ def test_size_1m (self):
+ """Test the size."""
+ self.connect ({"size": 1024*1024})
+ assert self.h.get_size() == 1024*1024
+
+ # Test each flag call.
+ def test_is_rotational_true (self):
+ self.connect ({"size": 512, "is_rotational": True})
+ assert self.h.is_rotational()
+
+ def test_is_rotational_false (self):
+ self.connect ({"size": 512, "is_rotational":
False})
+ assert not self.h.is_rotational()
+
+ def test_can_multi_conn_true (self):
+ self.connect ({"size": 512, "can_multi_conn":
True})
+ assert self.h.can_multi_conn()
+
+ def test_can_multi_conn_false (self):
+ self.connect ({"size": 512, "can_multi_conn":
False})
+ assert not self.h.can_multi_conn()
+
+ def test_read_write (self):
+ self.connect ({"size": 512, "can_write": True})
+ assert not self.h.is_read_only()
+
+ def test_read_only (self):
+ self.connect ({"size": 512, "can_write": False})
+ assert self.h.is_read_only()
+
+ def test_can_flush_true (self):
+ self.connect ({"size": 512, "can_flush": True})
+ assert self.h.can_flush()
+
+ def test_can_flush_false (self):
+ self.connect ({"size": 512, "can_flush": False})
+ assert not self.h.can_flush()
+
+ def test_can_trim_true (self):
+ self.connect ({"size": 512, "can_trim": True})
+ assert self.h.can_trim()
+
+ def test_can_trim_false (self):
+ self.connect ({"size": 512, "can_trim": False})
+ assert not self.h.can_trim()
+
+ # nbdkit can always zero because it emulates it.
+ #self.connect ({"size": 512, "can_zero": True})
+ #assert self.h.can_zero()
+ #self.connect ({"size": 512, "can_zero": False})
+ #assert not self.h.can_zero()
+
+ def test_can_fast_zero_true (self):
+ self.connect ({"size": 512, "can_fast_zero": True})
+ assert self.h.can_fast_zero()
+
+ def test_can_fast_zero_false (self):
+ self.connect ({"size": 512, "can_fast_zero":
False})
+ assert not self.h.can_fast_zero()
+
+ def test_can_fua_none (self):
+ self.connect ({"size": 512, "can_fua":
"none"})
+ assert not self.h.can_fua()
+
+ def test_can_fua_emulate (self):
+ self.connect ({"size": 512, "can_fua":
"emulate"})
+ assert self.h.can_fua()
+
+ def test_can_fua_native (self):
+ self.connect ({"size": 512, "can_fua":
"native"})
+ assert self.h.can_fua()
+
+ def test_can_cache_none (self):
+ self.connect ({"size": 512, "can_cache":
"none"})
+ assert not self.h.can_cache()
+
+ def test_can_cache_emulate (self):
+ self.connect ({"size": 512, "can_cache":
"emulate"})
+ assert self.h.can_cache()
+
+ def test_can_cache_native (self):
+ self.connect ({"size": 512, "can_cache":
"native"})
+ assert self.h.can_cache()
+
+ # Not yet implemented: can_extents.
+
+ def test_pread_bytearray (self):
+ """Test pread returning bytearray."""
+ self.connect ({"size": 512})
+ buf = self.h.pread (512, 0)
+ assert buf == bytearray (512)
+
+ def test_pread_bytes (self):
+ """Test pread returning bytes."""
+ self.connect ({"size": 512,
+ "pread_result": "bytes"})
+ buf = self.h.pread (512, 0)
+ assert buf == bytearray (512)
+
+ def test_pread_memoryview (self):
+ """Test pread returning memoryview."""
+ self.connect ({"size": 512,
+ "pread_result": "memoryview"})
+ buf = self.h.pread (512, 0)
+ assert buf == bytearray (512)
+
+ # Test pwrite + flags.
+ def test_pwrite (self):
+ self.connect ({"size": 512})
+ buf = bytearray (512)
+ self.h.pwrite (buf, 0)
+
+ def test_pwrite_fua (self):
+ self.connect ({"size": 512,
+ "can_fua": "native",
+ "pwrite_expect_fua": True})
+ buf = bytearray (512)
+ self.h.pwrite (buf, 0, nbd.CMD_FLAG_FUA)
+
+ def test_flush (self):
+ """Test flush."""
+ self.connect ({"size": 512, "can_flush": True})
+ self.h.flush ()
+
+ # Test trim + flags.
+ def test_trim (self):
+ self.connect ({"size": 512, "can_trim": True})
+ self.h.trim (512, 0)
+
+ def test_trim_fua (self):
+ self.connect ({"size": 512,
+ "can_trim": True,
+ "can_fua": "native",
+ "trim_expect_fua": True})
+ self.h.trim (512, 0, nbd.CMD_FLAG_FUA)
+
+ # Test zero + flags.
+ def test_zero (self):
+ self.connect ({"size": 512, "can_zero": True})
+ self.h.zero (512, 0, nbd.CMD_FLAG_NO_HOLE)
+
+ def test_zero_fua (self):
+ self.connect ({"size": 512,
+ "can_zero": True,
+ "can_fua": "native",
+ "zero_expect_fua": True})
+ self.h.zero (512, 0, nbd.CMD_FLAG_NO_HOLE | nbd.CMD_FLAG_FUA)
+
+ def test_zero_may_trim (self):
+ self.connect ({"size": 512,
+ "can_zero": True,
+ "zero_expect_may_trim": True})
+ self.h.zero (512, 0, 0) # absence of nbd.CMD_FLAG_NO_HOLE
+
+ def test_zero_fast_zero (self):
+ self.connect ({"size": 512,
+ "can_zero": True,
+ "can_fast_zero": True,
+ "zero_expect_fast_zero": True})
+ self.h.zero (512, 0, nbd.CMD_FLAG_NO_HOLE | nbd.CMD_FLAG_FAST_ZERO)
+
+ def test_cache (self):
+ """Test cache."""
+ self.connect ({"size": 512, "can_cache":
"native"})
+ self.h.cache (512, 0)
--
2.23.0
Apparently Analagous Threads
- [PATCH nbdkit v3 0/7] Implement nbdkit API v2 for Python plugins.
- [PATCH nbdkit v2 00/10] Implement nbdkit API v2 for Python plugins.
- [PATCH nbdkit 0/8] Implement nbdkit API v2 for Python plugins.
- [nbdkit PATCH 0/5] Counterproposal for python v2 interfaces
- [nbdkit PATCH 0/2] More caching of initial setup