search for: py_can_zero

Fairly straightforward, as the code in plugins.c already takes care of necessary .pwrite fallbacks. Simplify similar can_FOO callbacks that were copy-and-pasted while implementing py_can_zero. Signed-off-by: Eric Blake <eblake@redhat.com> --- plugins/python/nbdkit-python-plugin.pod | 7 +++++ plugins/python/python.c | 51 +++++++++++++++++++-------------- tests/test.py | 4 +++ 3 files changed, 41 insertions(+), 21 deletions(-) diff -...

...{ PyErr_Clear (); - r = PyObject_CallFunctionObjArgs (fn, obj, NULL); + r = PyObject_CallFunctionObjArgs (fn, h->obj, NULL); Py_DECREF (fn); if (check_python_failure ("can_trim") == -1) return -1; @@ -810,7 +825,7 @@ py_can_trim (void *handle) static int py_can_zero (void *handle) { - PyObject *obj = handle; + ConnHandle *h = handle; PyObject *fn; PyObject *r; int ret; @@ -818,7 +833,7 @@ py_can_zero (void *handle) if (callback_defined ("can_zero", &fn)) { PyErr_Clear (); - r = PyObject_CallFunctionObjArgs (fn, obj, NULL);...

First out of our four language bindings to add FUA support (for reference, I added 'zero' support for python, perl, and ruby back in 1.1.13, then Rich had to add it for ocaml in 1.1.20). I tested this heavily under python 2, but for now only compile tested under python 3; I plan to do further testing there and make any tweaks if necessary. I wrote patch 5 early on, but then realized I

...yObject_CallFunctionObjArgs (fn, obj, NULL); > + r = PyObject_CallFunctionObjArgs (fn, h->obj, NULL); > Py_DECREF (fn); > if (check_python_failure ("can_trim") == -1) > return -1; > @@ -810,7 +825,7 @@ py_can_trim (void *handle) > static int > py_can_zero (void *handle) > { > - PyObject *obj = handle; > + ConnHandle *h = handle; > PyObject *fn; > PyObject *r; > int ret; > @@ -818,7 +833,7 @@ py_can_zero (void *handle) > if (callback_defined ("can_zero", &fn)) { > PyErr_Clear (); > >...

As mentioned in my reviews, I wonder if we should make our python callbacks look a bit more Pythonic by having kwargs added for each new flag that we want to expose. The idea was first floated here: https://www.redhat.com/archives/libguestfs/2018-April/msg00108.html Note that with my proposal, there is no need for a python script to expose a global API_VERSION variable; new flags are added

...pen, + .close = py_close, - .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, - .can_zero = py_can_zero, - .can_fast_zero = py_can_fast_zero, - .can_fua = py_can_fua, - .can_cache = py_can_cache, - .can_extents = py_can_extents, + .export_description = py_export_description, + .get_size = py_get_size, + .is_rotational = py_is_rotational, + .can_multi...

...32_t count, uint64_t offset, uint32_t flags) if (check_python_failure ("zero") == -1) return -1; Py_DECREF (r); - return 0; + return need_flush ? py_flush (handle, 0) : 0; } nbdkit_debug ("zero missing, falling back to pwrite"); @@ -732,6 +830,40 @@ py_can_zero (void *handle) return callback_defined ("zero", NULL); } +static int +py_can_fua (void *handle) +{ + PyObject *obj = handle; + PyObject *fn; + PyObject *r; + int fua; + + /* We have to convert a python bool into the nbdkit tristate. */ + if (callback_defined ("can_fua&quot...

This is working for me now, although possibly only on Python 3.9. Dan suggested PyEval_InitThreads but that was deprecated in Python 3.7. Rich.

This picks up python and ocaml. Some of our languages are lacking a number of bindings (for example, lua and perl lack .extents, so I didn't have anything to copy from), and I felt less comfortable with golang and rust. But for python and ocaml, I was able to test a working implementation. Eric Blake (2): python: Implement .list_exports and friends ocaml: Implement .list_exports and

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.

v2 was here: https://www.redhat.com/archives/libguestfs/2019-November/msg00163.html I pushed patch 1 (with spelling fix), patch 4 and patch 5 since those were previously ACKed on the list. Differences in v3: - Add error checking to PyModule_AddIntConstant. - Use API_VERSION constant instead of function. - Add max API version supported to --dump-plugin output. - Print API_VERSION selected by

And fill out most of the missing bits of the API. Rich.

When I added .can_FOO caching in 1.16, I missed the case that the sh plugin itself was calling .can_flush twice in some situations (in order to default .can_fua). Then right after, I regressed it to call .can_zero twice (in order to default .can_fast_zero). I also missed that .thread_model could use better caching, because at the time, I did not add testsuite coverage. Fix that now. Eric Blake

On 3/18/20 8:21 PM, Eric Blake wrote: > In commit c306fa93ab and neighbors (v1.15.1), a concerted effort went > into caching the results of .can_FOO callbacks, with commit messages > demonstrating that a plugin with a slow callback should not have that > delay magnified multiple times. But nothing was added to the > testsuite at the time, and with the sh and eval plugins, we still

v1: https://www.redhat.com/archives/libguestfs/2019-November/msg00153.html v2: - Fix implementation of can_cache. - Add implementation of can_fua. - Add a very thorough test suite which tests every command + flag combination.

It's been several weeks since I posted v2 (I got distracted by improving libnbd to better test things, which in turn surfaced some major memory leak problems in nbdsh that are now fixed). Many of the patches are minor rebases from v2, with the biggest changes being fallout from: - patch 2: rename nbdkit_add_default_export to nbdkit_use_default_export - overall: this missed 1.22, so update