search for: filter_thread_model

....thread_model = xz_thread_model, .open = xz_open, .close = xz_close, .prepare = xz_prepare, diff --git a/server/filters.c b/server/filters.c index 87a9c0e..3d9e1ef 100644 --- a/server/filters.c +++ b/server/filters.c @@ -93,20 +93,18 @@ static int filter_thread_model (struct backend *b) { struct backend_filter *f = container_of (b, struct backend_filter, backend); - int filter_thread_model = f->filter._thread_model; + int filter_thread_model = NBDKIT_THREAD_MODEL_PARALLEL; int thread_model = f->backend.next->thread_model (f->backend.next);...

Being able to programmatically force nbdkit to be less parallel can be useful during testing. I was less sure about patch 3, but if you like it, I'm inclined to instead squash it into patch 1. This patch is written to apply after my NBD_CMD_CACHE work (since I touched the nocache filter); but can be rearranged if we think this series should go in first while that one undergoes any adjustments

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

...uct backend *b) { struct backend_filter *f = container_of (b, struct backend_filter, backend); - f->backend.next->free (f->backend.next); + b->next->free (b->next); /* Acquiring this lock prevents any filter callbacks from running * simultaneously. @@ -94,7 +94,7 @@ filter_thread_model (struct backend *b) { struct backend_filter *f = container_of (b, struct backend_filter, backend); int filter_thread_model = NBDKIT_THREAD_MODEL_PARALLEL; - int thread_model = f->backend.next->thread_model (f->backend.next); + int thread_model = b->next->thread_model (b->...

...me was always set to the name of the second filter. Also fixes an adjacent comment. --- src/filters.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/src/filters.c b/src/filters.c index 67f06d6..b68afab 100644 --- a/src/filters.c +++ b/src/filters.c @@ -103,15 +103,15 @@ filter_thread_model (struct backend *b) return thread_model; } -/* These are actually passing through to the final plugin, hence - * the function names. +/* This is actually passing the request through to the final plugin, + * hence the function name. */ static const char * plugin_name (struct backend *b) {...

...any filter callbacks from running + * simultaneously. + */ + lock_unload (); + + debug ("%s: unload", f->filename); + if (f->filter.unload) + f->filter.unload (); + + dlclose (f->dl); + free (f->filename); + + unlock_unload (); + + free (f); +} + +static int +filter_thread_model (struct backend *b) +{ + struct backend_filter *f = container_of (b, struct backend_filter, backend); + int filter_thread_model = NBDKIT_THREAD_MODEL_PARALLEL; + int thread_model; + + if (f->filter.limit_thread_model) + filter_thread_model = f->filter.limit_thread_model (); + + thread...

...;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_pread, .pwrite = filter_pwrite, .flush = filter_flush, .tri...

This is still tentative and needs a lot of work, but: - partition filter works, supporting MBR & GPT - prepare and finalize methods fixed - open method can now be changed (allowing readonly flag to be modified) - thread_model can be limited I believe I made most of the changes which were previously suggested in email. I think the only one I didn't was preventing inclusion of both

...rr); + 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_fua, .can_multi_conn = filter_can_multi_conn, .pread = filte...

...s_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_fua, .can_multi_conn = filter_can_multi_conn, .pread = filte...

...s_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_fua, .can_multi_conn = filter_can_multi_conn, .pread = filte...

It's easy to use the sh script to demonstrate that nbdkit is inefficiently calling into .get_size, .can_fua, and friends more than necessary. We've also commented on the list in the past that it would be nice to ensure that when filters call into next_ops, they are not violating constraints (as we've have to fix several bugs in the past where we did not have such checking to protect

...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_fua, .can_multi_conn = filter_can_multi_conn, .pread = filte...

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

...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_fua, .can_multi_conn = filter_can_multi_conn, .pread = filte...

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 -

...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_filter *f; const struct nbdkit_filter *filter; - size_t i, len;...

...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_fua, .can_multi_conn = filter_can_multi_conn, .pread = filte...

...{ lock_request (conn); error = handle_request (conn, cmd, flags, offset, count, buf); + assert ((int) error >= 0); unlock_request (conn); } diff --git a/src/filters.c b/src/filters.c index 40c4913..1003dc7 100644 --- a/src/filters.c +++ b/src/filters.c @@ -107,14 +107,6 @@ filter_thread_model (struct backend *b) /* These are actually passing through to the final plugin, hence * the function names. */ -static int -plugin_errno_is_preserved (struct backend *b) -{ - struct backend_filter *f = container_of (b, struct backend_filter, backend); - - return f->backend.next->errno_i...

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.