search for: plugin_free

When valgrinding plugins, the following sequence can happen: plugin_free -> dlclose -> unloads the plugin and symbol table exit -> valgrind prints failures (the same applies to filters). When valgrind is printing the failures, it looks up the addresses in the symbol table, but that has been unloaded already so all you see are "???", res...

...ge) (struct backend *); const char *(*version) (struct backend *); void (*dump_fields) (struct backend *); diff --git a/src/plugins.c b/src/plugins.c index 6a2ef66..f0fe864 100644 --- a/src/plugins.c +++ b/src/plugins.c @@ -465,6 +465,7 @@ static struct backend plugin_functions = { .free = plugin_free, .thread_model = plugin_thread_model, .name = plugin_name, + .plugin_name = plugin_name, .usage = plugin_usage, .version = plugin_version, .dump_fields = plugin_dump_fields, -- 2.15.1

...an differ for filters, should we also have a way to report independent version numbers (via .version) for the filter, compared to the version of the underlying plugin (via .plugin_version)? > +++ b/src/plugins.c > @@ -465,6 +465,7 @@ static struct backend plugin_functions = { > .free = plugin_free, > .thread_model = plugin_thread_model, > .name = plugin_name, > + .plugin_name = plugin_name, > .usage = plugin_usage, > .version = plugin_version, > .dump_fields = plugin_dump_fields, > -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-9...

...index 34cc3cb5..0f70ede0 100644 --- a/server/plugins.c +++ b/server/plugins.c @@ -54,9 +54,6 @@ */ struct backend_plugin { struct backend backend; - char *name; /* copy of plugin.name */ - char *filename; - void *dl; struct nbdkit_plugin plugin; }; @@ -65,22 +62,7 @@ plugin_free (struct backend *b) { struct backend_plugin *p = container_of (b, struct backend_plugin, backend); - /* Acquiring this lock prevents any plugin callbacks from running - * simultaneously. - */ - lock_unload (); - - debug ("%s: unload", p->name); - if (p->plugin.unload) -...

Somewhat invasive but mostly mechanical change to how plugins are called. This patch is in preparation for adding a second backend subtype for filters. Rich.

...dl; -static struct nbdkit_plugin plugin; - -void -plugin_register (const char *_filename, - void *_dl, struct nbdkit_plugin *(*plugin_init) (void)) +struct backend_plugin { + struct backend backend; + char *filename; + void *dl; + struct nbdkit_plugin plugin; +}; + +static void +plugin_free (struct backend *b) { - const struct nbdkit_plugin *_plugin; - size_t i, len, size; - - filename = strdup (_filename); - if (filename == NULL) { - perror ("strdup"); - exit (EXIT_FAILURE); - } - dl = _dl; - - debug ("registering %s", filename); - - /* Call the ini...

...dl; -static struct nbdkit_plugin plugin; - -void -plugin_register (const char *_filename, - void *_dl, struct nbdkit_plugin *(*plugin_init) (void)) +struct backend_plugin { + struct backend backend; + char *filename; + void *dl; + struct nbdkit_plugin plugin; +}; + +static void +plugin_free (struct backend *b) { - const struct nbdkit_plugin *_plugin; - size_t i, len, size; + struct backend_plugin *p = container_of (b, struct backend_plugin, backend); - filename = strdup (_filename); - if (filename == NULL) { - perror ("strdup"); - exit (EXIT_FAILURE); - } - d...

...dl; -static struct nbdkit_plugin plugin; - -void -plugin_register (const char *_filename, - void *_dl, struct nbdkit_plugin *(*plugin_init) (void)) +struct backend_plugin { + struct backend backend; + char *filename; + void *dl; + struct nbdkit_plugin plugin; +}; + +static void +plugin_free (struct backend *b) { - const struct nbdkit_plugin *_plugin; - size_t i, len, size; - - filename = strdup (_filename); - if (filename == NULL) { - perror ("strdup"); - exit (EXIT_FAILURE); - } - dl = _dl; - - debug ("registering %s", filename); - - /* Call the ini...

...assert (!flags); + + debug ("cache count=%" PRIu32 " offset=%" PRIu64, count, offset); + + /* FIXME: assert plugin->cache and call it */ + assert (false); + + if (r == -1) + *err = get_error (p); + return r; +} + static struct backend plugin_functions = { .free = plugin_free, .thread_model = plugin_thread_model, @@ -717,12 +749,14 @@ static struct backend plugin_functions = { .can_extents = plugin_can_extents, .can_fua = plugin_can_fua, .can_multi_conn = plugin_can_multi_conn, + .can_cache = plugin_can_cache, .pread = plugin_pread, .pwrite = plugin_p...

...= errno; + nbdkit_error ("calloc"); + return -1; + } + (*extents)[0].offset = offset; + (*extents)[0].length = count; + (*extents)[0].type = NBDKIT_EXTENT_TYPE_DATA; + *nr_extents = 1; + return 0; + } +} + static struct backend plugin_functions = { .free = plugin_free, .thread_model = plugin_thread_model, @@ -672,6 +740,7 @@ static struct backend plugin_functions = { .is_rotational = plugin_is_rotational, .can_trim = plugin_can_trim, .can_zero = plugin_can_zero, + .can_extents = plugin_can_extents, .can_fua = plugin_can_fua, .can_multi_conn =...

v1 -> v2: - Fixed everything mentioned in the review. Rich.

...et_error (p); + return r; + } + else { + /* By default we assume that everything in the range is allocated. */ + return nbdkit_extent_add (extents_map, offset, count, + NBDKIT_EXTENT_TYPE_DATA); + } +} + static struct backend plugin_functions = { .free = plugin_free, .thread_model = plugin_thread_model, @@ -672,6 +731,7 @@ static struct backend plugin_functions = { .is_rotational = plugin_is_rotational, .can_trim = plugin_can_trim, .can_zero = plugin_can_zero, + .can_extents = plugin_can_extents, .can_fua = plugin_can_fua, .can_multi_conn =...

...lags, extents_map); + if (r == -1) + *err = get_error (p); + return r; + } + else { + /* By default we assume that everything in the range is allocated. */ + return nbdkit_extent_add (extents_map, offset, count, 0); + } +} + static struct backend plugin_functions = { .free = plugin_free, .thread_model = plugin_thread_model, @@ -672,6 +730,7 @@ static struct backend plugin_functions = { .is_rotational = plugin_is_rotational, .can_trim = plugin_can_trim, .can_zero = plugin_can_zero, + .can_extents = plugin_can_extents, .can_fua = plugin_can_fua, .can_multi_conn =...

...&& nbdkit_extents_count (extents) < 1) { + nbdkit_error ("extents: plugin must return at least one extent"); + nbdkit_set_error (EINVAL); + r = -1; + } + if (r == -1) + *err = get_error (p); + return r; +} + static struct backend plugin_functions = { .free = plugin_free, .thread_model = plugin_thread_model, @@ -672,6 +722,7 @@ static struct backend plugin_functions = { .is_rotational = plugin_is_rotational, .can_trim = plugin_can_trim, .can_zero = plugin_can_zero, + .can_extents = plugin_can_extents, .can_fua = plugin_can_fua, .can_multi_conn =...

This tentative commit implements extents/can_extents, roughly as discussed in the previous thread here: https://www.redhat.com/archives/libguestfs/2019-March/msg00017.html I can't say that I'm a big fan of having the plugin allocate an extents array. There are no other plugin callbacks currently where we require the plugin to allocate complex data structures (or indeed do any allocation

.../* By default we assume that everything in the range is allocated. */ + errno = 0; + r = nbdkit_add_extent (extents, offset, count, 0 /* allocated data */); + if (r == -1) + *err = errno ? errno : EINVAL; + return r; + } +} + static struct backend plugin_functions = { .free = plugin_free, .thread_model = plugin_thread_model, @@ -672,6 +729,7 @@ static struct backend plugin_functions = { .is_rotational = plugin_is_rotational, .can_trim = plugin_can_trim, .can_zero = plugin_can_zero, + .can_extents = plugin_can_extents, .can_fua = plugin_can_fua, .can_multi_conn =...

I'm not sure which version we're up to now. Anyway I believe this addresses all the points that Eric raised in: https://www.redhat.com/archives/libguestfs/2019-March/msg00038.html https://www.redhat.com/archives/libguestfs/2019-March/msg00040.html In particular: - default state of extents_map is all allocated disk - support hole + non-zero - you can now iterate with bounds -

...&& nbdkit_extents_count (extents) < 1) { + nbdkit_error ("extents: plugin must return at least one extent"); + nbdkit_set_error (EINVAL); + r = -1; + } + if (r == -1) + *err = get_error (p); + return r; +} + static struct backend plugin_functions = { .free = plugin_free, .thread_model = plugin_thread_model, @@ -672,6 +722,7 @@ static struct backend plugin_functions = { .is_rotational = plugin_is_rotational, .can_trim = plugin_can_trim, .can_zero = plugin_can_zero, + .can_extents = plugin_can_extents, .can_fua = plugin_can_fua, .can_multi_conn =...

Second version based on nbdkit_extent* calls, as discussed here: https://www.redhat.com/archives/libguestfs/2019-March/msg00033.html Note in particular there is some subtlety about how filters would work in this implementation. See docs/nbdkit-filter.pod for the details. Rich.

The first three patches are identical to: https://www.redhat.com/archives/libguestfs/2018-January/msg00079.html "[PATCH nbdkit v2 0/3] Refactor plugin_* functions into a backend" The rest of the patches add filters using the new filter API previously described here: https://www.redhat.com/archives/libguestfs/2018-January/msg00073.html This needs a lot more testing -- and tests --