[PULL 19/25] migration: remove the QEMUFileOps 'shut_down' callback

From: Juan Quintela <quintela@redhat.com>
To: qemu-devel@nongnu.org
Cc: "Hailiang Zhang" <zhanghailiang@xfusion.com>,
	"Eric Blake" <eblake@redhat.com>,
	"Daniel P. Berrangé" <berrange@redhat.com>,
	"Fam Zheng" <fam@euphon.net>,
	"Dr. David Alan Gilbert" <dgilbert@redhat.com>,
	"Juan Quintela" <quintela@redhat.com>,
	qemu-block@nongnu.org, "Stefan Hajnoczi" <stefanha@redhat.com>,
	"Markus Armbruster" <armbru@redhat.com>
Subject: [PULL 19/25] migration: remove the QEMUFileOps 'shut_down' callback
Date: Wed, 22 Jun 2022 02:25:41 +0200	[thread overview]
Message-ID: <20220622002547.64784-20-quintela@redhat.com> (raw)
In-Reply-To: <20220622002547.64784-1-quintela@redhat.com>

From: Daniel P. Berrangé <berrange@redhat.com>

This directly implements the shutdown logic using QIOChannel APIs.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 migration/qemu-file.h         | 10 ----------
 migration/qemu-file-channel.c | 27 ---------------------------
 migration/qemu-file.c         | 13 ++++++++++---
 3 files changed, 10 insertions(+), 40 deletions(-)

diff --git a/migration/qemu-file.h b/migration/qemu-file.h
index fe1b2d1c00..9fa92c1998 100644
--- a/migration/qemu-file.h
+++ b/migration/qemu-file.h
@@ -89,22 +89,12 @@ typedef size_t (QEMURamSaveFunc)(QEMUFile *f,
  */
 typedef QEMUFile *(QEMURetPathFunc)(void *opaque);
 
-/*
- * Stop any read or write (depending on flags) on the underlying
- * transport on the QEMUFile.
- * Existing blocking reads/writes must be woken
- * Returns 0 on success, -err on error
- */
-typedef int (QEMUFileShutdownFunc)(void *opaque, bool rd, bool wr,
-                                   Error **errp);
-
 typedef struct QEMUFileOps {
     QEMUFileGetBufferFunc *get_buffer;
     QEMUFileCloseFunc *close;
     QEMUFileSetBlocking *set_blocking;
     QEMUFileWritevBufferFunc *writev_buffer;
     QEMURetPathFunc *get_return_path;
-    QEMUFileShutdownFunc *shut_down;
 } QEMUFileOps;
 
 typedef struct QEMUFileHooks {
diff --git a/migration/qemu-file-channel.c b/migration/qemu-file-channel.c
index 5cb8ac93c0..80f05dc371 100644
--- a/migration/qemu-file-channel.c
+++ b/migration/qemu-file-channel.c
@@ -112,31 +112,6 @@ static int channel_close(void *opaque, Error **errp)
 }
 
 
-static int channel_shutdown(void *opaque,
-                            bool rd,
-                            bool wr,
-                            Error **errp)
-{
-    QIOChannel *ioc = QIO_CHANNEL(opaque);
-
-    if (qio_channel_has_feature(ioc,
-                                QIO_CHANNEL_FEATURE_SHUTDOWN)) {
-        QIOChannelShutdown mode;
-        if (rd && wr) {
-            mode = QIO_CHANNEL_SHUTDOWN_BOTH;
-        } else if (rd) {
-            mode = QIO_CHANNEL_SHUTDOWN_READ;
-        } else {
-            mode = QIO_CHANNEL_SHUTDOWN_WRITE;
-        }
-        if (qio_channel_shutdown(ioc, mode, errp) < 0) {
-            return -EIO;
-        }
-    }
-    return 0;
-}
-
-
 static int channel_set_blocking(void *opaque,
                                 bool enabled,
                                 Error **errp)
@@ -166,7 +141,6 @@ static QEMUFile *channel_get_output_return_path(void *opaque)
 static const QEMUFileOps channel_input_ops = {
     .get_buffer = channel_get_buffer,
     .close = channel_close,
-    .shut_down = channel_shutdown,
     .set_blocking = channel_set_blocking,
     .get_return_path = channel_get_input_return_path,
 };
@@ -175,7 +149,6 @@ static const QEMUFileOps channel_input_ops = {
 static const QEMUFileOps channel_output_ops = {
     .writev_buffer = channel_writev_buffer,
     .close = channel_close,
-    .shut_down = channel_shutdown,
     .set_blocking = channel_set_blocking,
     .get_return_path = channel_get_output_return_path,
 };
diff --git a/migration/qemu-file.c b/migration/qemu-file.c
index c181686e41..6e79de1404 100644
--- a/migration/qemu-file.c
+++ b/migration/qemu-file.c
@@ -71,16 +71,23 @@ struct QEMUFile {
 /*
  * Stop a file from being read/written - not all backing files can do this
  * typically only sockets can.
+ *
+ * TODO: convert to propagate Error objects instead of squashing
+ * to a fixed errno value
  */
 int qemu_file_shutdown(QEMUFile *f)
 {
-    int ret;
+    int ret = 0;
 
     f->shutdown = true;
-    if (!f->ops->shut_down) {
+    if (!qio_channel_has_feature(f->ioc,
+                                 QIO_CHANNEL_FEATURE_SHUTDOWN)) {
         return -ENOSYS;
     }
-    ret = f->ops->shut_down(f->ioc, true, true, NULL);
+
+    if (qio_channel_shutdown(f->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL) < 0) {
+        ret = -EIO;
+    }
 
     if (!f->last_error) {
         qemu_file_set_error(f, -EIO);
-- 
2.35.3


