blktap2: Sort out tapdisk IPC init.

Move I/O and event callbacks setup out of tapdisk-server, into
tapdisk-ipc.

Signed-off-by: Daniel Stodden <daniel.stodden@citrix.com>

4 files changed, 95 insertions, 58 deletions

diff --git a/tools/blktap2/drivers/tapdisk-ipc.c b/tools/blktap2/drivers/tapdisk-ipc.c
index 3cfdb6c8f8..988e1c2c8f 100644
--- a/tools/blktap2/drivers/tapdisk-ipc.c
+++ b/tools/blktap2/drivers/tapdisk-ipc.c
@@ -30,12 +30,86 @@
 #include <stdlib.h>
 #include <unistd.h>
 #include <string.h>
+#include <fcntl.h>
 
 #include "tapdisk.h"
 #include "tapdisk-ipc.h"
 #include "tapdisk-vbd.h"
 #include "tapdisk-server.h"
 
+static void
+tapdisk_ipc_read_event(event_id_t id, char mode, void *private)
+{
+	td_ipc_t *ipc = private;
+	tapdisk_ipc_read(ipc);
+}
+
+static void
+__tapdisk_ipc_init(td_ipc_t *ipc)
+{
+	ipc->rfd = -1;
+	ipc->wfd = -1;
+	ipc->rfd_event = -1;
+}
+
+int
+tapdisk_ipc_open(td_ipc_t *ipc, const char *read, const char *write)
+{
+	int err;
+
+	memset(ipc, 0, sizeof(td_ipc_t));
+	__tapdisk_ipc_init(ipc);
+
+	if (read) {
+		ipc->rfd = open(read, O_RDWR | O_NONBLOCK);
+		if (ipc->rfd < 0) {
+			err = -errno;
+			EPRINTF("FD open failed %s: %d\n", read, err);
+			goto fail;
+		}
+
+		ipc->rfd_event = 
+			tapdisk_server_register_event(SCHEDULER_POLL_READ_FD,
+						      ipc->rfd, 0,
+						      tapdisk_ipc_read_event,
+						      ipc);
+		if (ipc->rfd_event < 0) {
+			err = ipc->rfd_event;
+			goto fail;
+		}
+	}
+
+	if (write) {
+		ipc->wfd = open(write, O_RDWR | O_NONBLOCK);
+		if (ipc->wfd < 0) {
+			err = -errno;
+			EPRINTF("FD open failed %s, %d\n", write, err);
+			goto fail;
+		}
+	}
+
+	return 0;
+
+fail:
+	tapdisk_ipc_close(ipc);
+	return err;
+}
+
+void
+tapdisk_ipc_close(td_ipc_t *ipc)
+{
+	if (ipc->rfd > 0)
+		close(ipc->rfd);
+
+	if (ipc->wfd > 0)
+		close(ipc->wfd);
+
+	if (ipc->rfd_event >= 0)
+		tapdisk_server_unregister_event(ipc->rfd_event);
+
+	__tapdisk_ipc_init(ipc);
+}
+
 static int
 tapdisk_ipc_write_message(int fd, tapdisk_message_t *message, int timeout)
 {
diff --git a/tools/blktap2/drivers/tapdisk-ipc.h b/tools/blktap2/drivers/tapdisk-ipc.h
index 25eb48cafc..c213d17795 100644
--- a/tools/blktap2/drivers/tapdisk-ipc.h
+++ b/tools/blktap2/drivers/tapdisk-ipc.h
@@ -29,13 +29,17 @@
 #define _TAPDISK_IPC_H_
 
 #include "tapdisk-message.h"
+#include "scheduler.h"
 
 typedef struct td_ipc_handle {
 	int                         rfd;
 	int                         wfd;
+	event_id_t		    rfd_event;
 	td_uuid_t                   uuid;
 } td_ipc_t;
 
+int tapdisk_ipc_open(td_ipc_t *ipc, const char *read, const char *write);
+void tapdisk_ipc_close(td_ipc_t *ipc);
 int tapdisk_ipc_read(td_ipc_t *ipc);
 int tapdisk_ipc_write(td_ipc_t *ipc, int type);
 int tapdisk_ipc_write_error(td_ipc_t *ipc, const char *message);
diff --git a/tools/blktap2/drivers/tapdisk-server.c b/tools/blktap2/drivers/tapdisk-server.c
index 4d9c426f4a..4e74e30a48 100644
--- a/tools/blktap2/drivers/tapdisk-server.c
+++ b/tools/blktap2/drivers/tapdisk-server.c
@@ -26,7 +26,6 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 #include <stdio.h>
-#include <fcntl.h>
 #include <errno.h>
 #include <unistd.h>
 #include <stdlib.h>
@@ -223,12 +222,6 @@ tapdisk_server_send_error(const char *message)
 }
 
 static void
-tapdisk_server_read_ipc_message(event_id_t id, char mode, void *private)
-{
-	tapdisk_ipc_read(&server.ipc);
-}
-
-static void
 tapdisk_server_aio_queue_event(event_id_t id, char mode, void *private)
 {
 	tapdisk_complete_tiocbs(&server.aio_queue);
@@ -242,6 +235,18 @@ tapdisk_server_free_aio_queue(void)
 }
 
 static int
+tapdisk_server_init_ipc(const char *read, const char *write)
+{
+	return tapdisk_ipc_open(&server.ipc, read, write);
+}
+
+static void
+tapdisk_server_close_ipc(void)
+{
+	tapdisk_ipc_close(&server.ipc);
+}
+
+static int
 tapdisk_server_initialize_aio_queue(void)
 {
 	int err;
@@ -270,15 +275,7 @@ static void
 tapdisk_server_close(void)
 {
 	tapdisk_server_free_aio_queue();
-
-	if (server.control_event)
-		scheduler_unregister_event(&server.scheduler, server.control_event);
-
-	if (server.ipc.rfd != -1)
-		close(server.ipc.rfd);
-
-	if (server.ipc.wfd != -1)
-		close(server.ipc.wfd);
+	tapdisk_server_close_ipc();
 }
 
 static void
@@ -334,63 +331,26 @@ int
 tapdisk_server_initialize(const char *read, const char *write)
 {
 	int err;
-	event_id_t event_id;
 
-	event_id = 0;
 	memset(&server, 0, sizeof(tapdisk_server_t));
-	server.ipc.rfd = server.ipc.wfd = -1;
-
 	INIT_LIST_HEAD(&server.vbds);
 
-	if (read) {
-		server.ipc.rfd = open(read, O_RDWR | O_NONBLOCK);
-		if (server.ipc.rfd < 0) {
-			err = -errno;
-			EPRINTF("FD open failed %s: %d\n", read, err);
-			goto fail;
-		}
-	}
-
-	if (write) {
-		server.ipc.wfd = open(write, O_RDWR | O_NONBLOCK);
-		if (server.ipc.wfd < 0) {
-			err = -errno;
-			EPRINTF("FD open failed %s, %d\n", write, err);
-			goto fail;
-		}
-	}
-
 	scheduler_initialize(&server.scheduler);
 
-	if (read) {
-		event_id = scheduler_register_event(&server.scheduler,
-						    SCHEDULER_POLL_READ_FD,
-						    server.ipc.rfd, 0,
-						    tapdisk_server_read_ipc_message,
-						    NULL);
-		if (event_id < 0) {
-			err = event_id;
-			goto fail;
-		}
-	}
+	err = tapdisk_server_init_ipc(read, write);
+	if (err)
+		goto fail;
 
 	err = tapdisk_server_initialize_aio_queue();
 	if (err)
 		goto fail;
 
-	server.control_event = event_id;
 	server.run = 1;
 
 	return 0;
 
 fail:
-	if (server.ipc.rfd > 0)
-		close(server.ipc.rfd);
-	if (server.ipc.wfd > 0)
-		close(server.ipc.wfd);
-	if (event_id > 0)
-		scheduler_unregister_event(&server.scheduler,
-					   server.control_event);
+	tapdisk_server_close_ipc();
 	return err;
 }
 
diff --git a/tools/blktap2/drivers/tapdisk-server.h b/tools/blktap2/drivers/tapdisk-server.h
index 09a4e13b81..ffdc579183 100644
--- a/tools/blktap2/drivers/tapdisk-server.h
+++ b/tools/blktap2/drivers/tapdisk-server.h
@@ -57,7 +57,6 @@ typedef struct tapdisk_server {
 	td_ipc_t                     ipc;
 	struct list_head             vbds;
 	scheduler_t                  scheduler;
-	event_id_t                   control_event;
 	struct tqueue                aio_queue;
 	event_id_t                   aio_queue_event_id;
 } tapdisk_server_t;