nbd: Follow the BDS' AIO context

Keep the NBD server always in the same AIO context as the exported BDS
by calling bdrv_add_aio_context_notifier() and implementing the required
callbacks.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Max Reitz 2014-06-20 21:57:34 +02:00 committed by Stefan Hajnoczi
parent 33384421b3
commit f21492817b

31
nbd.c
View File

@ -929,6 +929,34 @@ static void nbd_request_put(NBDRequest *req)
nbd_client_put(client); nbd_client_put(client);
} }
static void bs_aio_attached(AioContext *ctx, void *opaque)
{
NBDExport *exp = opaque;
NBDClient *client;
TRACE("Export %s: Attaching clients to AIO context %p\n", exp->name, ctx);
exp->ctx = ctx;
QTAILQ_FOREACH(client, &exp->clients, next) {
nbd_set_handlers(client);
}
}
static void bs_aio_detach(void *opaque)
{
NBDExport *exp = opaque;
NBDClient *client;
TRACE("Export %s: Detaching clients from AIO context %p\n", exp->name, exp->ctx);
QTAILQ_FOREACH(client, &exp->clients, next) {
nbd_unset_handlers(client);
}
exp->ctx = NULL;
}
NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset, NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset,
off_t size, uint32_t nbdflags, off_t size, uint32_t nbdflags,
void (*close)(NBDExport *)) void (*close)(NBDExport *))
@ -943,6 +971,7 @@ NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset,
exp->close = close; exp->close = close;
exp->ctx = bdrv_get_aio_context(bs); exp->ctx = bdrv_get_aio_context(bs);
bdrv_ref(bs); bdrv_ref(bs);
bdrv_add_aio_context_notifier(bs, bs_aio_attached, bs_aio_detach, exp);
return exp; return exp;
} }
@ -990,6 +1019,8 @@ void nbd_export_close(NBDExport *exp)
nbd_export_set_name(exp, NULL); nbd_export_set_name(exp, NULL);
nbd_export_put(exp); nbd_export_put(exp);
if (exp->bs) { if (exp->bs) {
bdrv_remove_aio_context_notifier(exp->bs, bs_aio_attached,
bs_aio_detach, exp);
bdrv_unref(exp->bs); bdrv_unref(exp->bs);
exp->bs = NULL; exp->bs = NULL;
} }