search for: filter_functions

...et, flags, + nr_extents, extents, err); + else + return f->backend.next->extents (f->backend.next, conn, + count, offset, flags, + nr_extents, extents, err); +} + static struct backend filter_functions = { .free = filter_free, .thread_model = filter_thread_model, @@ -667,6 +726,7 @@ static struct backend filter_functions = { .is_rotational = filter_is_rotational, .can_trim = filter_can_trim, .can_zero = filter_can_zero, + .can_extents = filter_can_extents, .can_fua = filter_can...

...count, offset, flags, + extents_map, err); + else + return f->backend.next->extents (f->backend.next, conn, + count, offset, flags, + extents_map, err); +} + static struct backend filter_functions = { .free = filter_free, .thread_model = filter_thread_model, @@ -667,6 +726,7 @@ static struct backend filter_functions = { .is_rotational = filter_is_rotational, .can_trim = filter_can_trim, .can_zero = filter_can_zero, + .can_extents = filter_can_extents, .can_fua = filter_can...

...et=%" PRIu64 " flags=0x%" PRIx32, + f->name, count, offset, flags); + + /* FIXME: Allow filter to rewrite request */ + return f->backend.next->cache (f->backend.next, conn, + count, offset, flags, err); +} + static struct backend filter_functions = { .free = filter_free, .thread_model = filter_thread_model, @@ -726,12 +755,14 @@ static struct backend filter_functions = { .can_extents = filter_can_extents, .can_fua = filter_can_fua, .can_multi_conn = filter_can_multi_conn, + .can_cache = filter_can_cache, .pread = filter_p...

...count, offset, flags, + extents_map, err); + else + return f->backend.next->extents (f->backend.next, conn, + count, offset, flags, + extents_map, err); +} + static struct backend filter_functions = { .free = filter_free, .thread_model = filter_thread_model, @@ -667,6 +726,7 @@ static struct backend filter_functions = { .is_rotational = filter_is_rotational, .can_trim = filter_can_trim, .can_zero = filter_can_zero, + .can_extents = filter_can_extents, .can_fua = filter_can...

...count, offset, flags, + extents, err); + else + return f->backend.next->extents (f->backend.next, conn, + count, offset, flags, + extents, err); +} + static struct backend filter_functions = { .free = filter_free, .thread_model = filter_thread_model, @@ -667,6 +724,7 @@ static struct backend filter_functions = { .is_rotational = filter_is_rotational, .can_trim = filter_can_trim, .can_zero = filter_can_zero, + .can_extents = filter_can_extents, .can_fua = filter_can...

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

...count, offset, flags, + extents, err); + else + return f->backend.next->extents (f->backend.next, conn, + count, offset, flags, + extents, err); +} + static struct backend filter_functions = { .free = filter_free, .thread_model = filter_thread_model, @@ -667,6 +724,7 @@ static struct backend filter_functions = { .is_rotational = filter_is_rotational, .can_trim = filter_can_trim, .can_zero = filter_can_zero, + .can_extents = filter_can_extents, .can_fua = filter_can...

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 -

...count, offset, flags, + extents, err); + else + return f->backend.next->extents (f->backend.next, conn, + count, offset, flags, + extents, err); +} + static struct backend filter_functions = { .free = filter_free, .thread_model = filter_thread_model, @@ -667,6 +724,7 @@ static struct backend filter_functions = { .is_rotational = filter_is_rotational, .can_trim = filter_can_trim, .can_zero = filter_can_zero, + .can_extents = filter_can_extents, .can_fua = filter_can...

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.

...count, offset, flags, + extents_map, err); + else + return f->backend.next->extents (f->backend.next, conn, + count, offset, flags, + extents_map, err); +} + static struct backend filter_functions = { .free = filter_free, .thread_model = filter_thread_model, @@ -667,6 +726,7 @@ static struct backend filter_functions = { .is_rotational = filter_is_rotational, .can_trim = filter_can_trim, .can_zero = filter_can_zero, + .can_extents = filter_can_extents, .can_fua = filter_can...

...uot; PRIx32, - f->name, count, offset, flags); + b->name, count, offset, flags); if (f->filter.cache) return f->filter.cache (&next_ops, &nxdata, handle, @@ -788,7 +762,6 @@ filter_cache (struct backend *b, struct connection *conn, static struct backend filter_functions = { .free = filter_free, .thread_model = filter_thread_model, - .name = filter_name, .plugin_name = plugin_name, .usage = filter_usage, .version = filter_version, @@ -826,7 +799,6 @@ filter_register (struct backend *next, size_t index, const char *filename, { struct backend_filt...

...p the malloc() wrapper around the handle altogether (test-layers.sh will confirm that we still have a stable pointer). That can be a separate patch; for the sake of _this_ patch, keeping things mechanical (with maybe a tweak to the comment) is fine. > } > > static struct backend filter_functions = { > diff --git a/server/locks.c b/server/locks.c > index ef6726d8..d187b422 100644 > --- a/server/locks.c > +++ b/server/locks.c > @@ -91,8 +91,12 @@ unlock_connection (void) > } > > void > -lock_request (struct connection *conn) > +lock_request (void) >...

...>zero (f->backend.next, conn, - count, offset, flags); + r = f->backend.next->zero (f->backend.next, conn, + count, offset, flags); + assert (r >= 0 && r != ENOTSUP); + return r; } static struct backend filter_functions = { @@ -567,7 +589,6 @@ static struct backend filter_functions = { .dump_fields = filter_dump_fields, .config = filter_config, .config_complete = filter_config_complete, - .errno_is_preserved = plugin_errno_is_preserved, .open = filter_open, .prepare = filter_prepare, .finalize =...

...&next_ops, &nxdata, handle); + else + return f->backend.next->can_multi_conn (f->backend.next, conn); +} + static int filter_pread (struct backend *b, struct connection *conn, void *buf, uint32_t count, uint64_t offset, @@ -645,6 +668,7 @@ static struct backend filter_functions = { .can_trim = filter_can_trim, .can_zero = filter_can_zero, .can_fua = filter_can_fua, + .can_multi_conn = filter_can_multi_conn, .pread = filter_pread, .pwrite = filter_pwrite, .flush = filter_flush, diff --git a/server/plugins.c b/server/plugins.c index cb0f411..bbde578 10064...

...->filter.ready_to_serve) { + if (f->filter.ready_to_serve (next_ready_to_serve, b->next) == -1) + exit (EXIT_FAILURE); + } + else + b->next->ready_to_serve (b->next); +} + static int next_open (void *nxdata, int readonly) { @@ -668,6 +691,7 @@ static struct backend filter_functions = { .config = filter_config, .config_complete = filter_config_complete, .magic_config_key = plugin_magic_config_key, + .ready_to_serve = filter_ready_to_serve, .open = filter_open, .prepare = filter_prepare, .finalize = filter_finalize, diff --git a/server/internal.h b/server/int...

...er.zero) + return f->filter.zero (&next_functions, &nxdata, handle, + count, offset, may_trim); + else + return f->backend.next->zero (f->backend.next, conn, + count, offset, may_trim); +} + +static struct backend filter_functions = { + .free = filter_free, + .thread_model = plugin_thread_model, + .name = filter_name, + .plugin_name = plugin_name, + .usage = filter_usage, + .version = filter_version, + .dump_fields = filter_dump_fields, + .config = filter_config, + .config_complete = filter_config_complete, + .errn...

...n_fua (&next_ops, &nxdata, handle); + else + return f->backend.next->can_fua (f->backend.next, conn); +} + static int filter_pread (struct backend *b, struct connection *conn, void *buf, uint32_t count, uint64_t offset, @@ -582,6 +628,8 @@ static struct backend filter_functions = { .flush = filter_flush, .trim = filter_trim, .zero = filter_zero, + .can_zero = filter_can_zero, + .can_fua = filter_can_fua, }; /* Register and load a filter. */ @@ -626,15 +674,23 @@ filter_register (struct backend *next, size_t index, const char *filename, exit (EXIT_FAILUR...

I'm still working my way through the filters before this series will be complete, but this is enough of a start to at least get some feedback on the idea of implementing another NBD protocol extension. Eric Blake (9): server: Internal hooks for implementing NBD_CMD_CACHE plugins: Add .cache callback file, split: Implement .cache with posix_fadvise nbd: Implement NBD_CMD_CACHE

...!(flags & ~(NBDKIT_FLAG_MAY_TRIM | NBDKIT_FLAG_FUA | + NBDKIT_FLAG_FAST_ZERO))); debug ("%s: zero count=%" PRIu32 " offset=%" PRIu64 " flags=0x%" PRIx32, f->name, count, offset, flags); @@ -818,6 +831,7 @@ static struct backend filter_functions = { .is_rotational = filter_is_rotational, .can_trim = filter_can_trim, .can_zero = filter_can_zero, + .can_fast_zero = filter_can_fast_zero, .can_extents = filter_can_extents, .can_fua = filter_can_fua, .can_multi_conn = filter_can_multi_conn, diff --git a/server/plugins.c b/ser...