ioengine: allow several external ioengines

Currently only one external ioengine can be exported because
it use hardcoded 'ioengine' symbol, but if we allow external
modules to have ops symbol similar to it's name then several
extrnal engines become possible.

NOTE: Old linking layout preserved

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/ioengines.c b/ioengines.c
index b43374e7afebb03a63d059fd5f09a36d582e67ba..c2a64cb092786519746ef82111e19bd1a79300fb 100644 (file)
--- a/ioengines.c
+++ b/ioengines.c
@@ -104,7 +104,9 @@ static struct ioengine_ops *dlopen_ioengine(struct thread_data *td,
         * Unlike the included modules, external engines should have a
         * non-static ioengine structure that we can reference.
         */
-       ops = dlsym(dlhandle, "ioengine");
+       ops = dlsym(dlhandle, engine_lib);
+       if (!ops)
+               ops = dlsym(dlhandle, "ioengine");
        if (!ops) {
                td_vmsg(td, -1, dlerror(), "dlsym");
                dlclose(dlhandle);