[Qemu-devel] [PATCH v4 05/28] migration: split migration hooks out of QEMUFileOps

["Daniel P. Berrange" <berrange@redhat.com>]

The QEMUFileOps struct contains the I/O subsystem callbacks
and the migration stage hooks. Split the hooks out into a
separate QEMUFileHooks struct to make it easier to refactor
the I/O side of QEMUFile without affecting the hooks.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
---
 include/migration/qemu-file.h  | 10 +++++++---
 migration/qemu-file-internal.h |  1 +
 migration/qemu-file.c          | 24 +++++++++++++++---------
 migration/rdma.c               |  8 ++++++++
 4 files changed, 31 insertions(+), 12 deletions(-)

diff --git a/include/migration/qemu-file.h b/include/migration/qemu-file.h
index 5909ff0..1934a64 100644
--- a/include/migration/qemu-file.h
+++ b/include/migration/qemu-file.h
@@ -108,13 +108,16 @@ typedef struct QEMUFileOps {
     QEMUFileCloseFunc *close;
     QEMUFileGetFD *get_fd;
     QEMUFileWritevBufferFunc *writev_buffer;
+    QEMURetPathFunc *get_return_path;
+    QEMUFileShutdownFunc *shut_down;
+} QEMUFileOps;
+
+typedef struct QEMUFileHooks {
     QEMURamHookFunc *before_ram_iterate;
     QEMURamHookFunc *after_ram_iterate;
     QEMURamHookFunc *hook_ram_load;
     QEMURamSaveFunc *save_page;
-    QEMURetPathFunc *get_return_path;
-    QEMUFileShutdownFunc *shut_down;
-} QEMUFileOps;
+} QEMUFileHooks;
 
 struct QEMUSizedBuffer {
     struct iovec *iov;
@@ -129,6 +132,7 @@ QEMUFile *qemu_fdopen(int fd, const char *mode);
 QEMUFile *qemu_fopen_socket(int fd, const char *mode);
 QEMUFile *qemu_popen_cmd(const char *command, const char *mode);
 QEMUFile *qemu_bufopen(const char *mode, QEMUSizedBuffer *input);
+void qemu_file_set_hooks(QEMUFile *f, const QEMUFileHooks *hooks);
 int qemu_get_fd(QEMUFile *f);
 int qemu_fclose(QEMUFile *f);
 int64_t qemu_ftell(QEMUFile *f);
diff --git a/migration/qemu-file-internal.h b/migration/qemu-file-internal.h
index d95e853..8fdfa95 100644
--- a/migration/qemu-file-internal.h
+++ b/migration/qemu-file-internal.h
@@ -33,6 +33,7 @@
 
 struct QEMUFile {
     const QEMUFileOps *ops;
+    const QEMUFileHooks *hooks;
     void *opaque;
 
     int64_t bytes_xfer;
diff --git a/migration/qemu-file.c b/migration/qemu-file.c
index 656db4a..b480b72 100644
--- a/migration/qemu-file.c
+++ b/migration/qemu-file.c
@@ -80,6 +80,12 @@ QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops)
     return f;
 }
 
+
+void qemu_file_set_hooks(QEMUFile *f, const QEMUFileHooks *hooks)
+{
+    f->hooks = hooks;
+}
+
 /*
  * Get last error for stream f
  *
@@ -149,8 +155,8 @@ void ram_control_before_iterate(QEMUFile *f, uint64_t flags)
 {
     int ret = 0;
 
-    if (f->ops->before_ram_iterate) {
-        ret = f->ops->before_ram_iterate(f, f->opaque, flags, NULL);
+    if (f->hooks && f->hooks->before_ram_iterate) {
+        ret = f->hooks->before_ram_iterate(f, f->opaque, flags, NULL);
         if (ret < 0) {
             qemu_file_set_error(f, ret);
         }
@@ -161,8 +167,8 @@ void ram_control_after_iterate(QEMUFile *f, uint64_t flags)
 {
     int ret = 0;
 
-    if (f->ops->after_ram_iterate) {
-        ret = f->ops->after_ram_iterate(f, f->opaque, flags, NULL);
+    if (f->hooks && f->hooks->after_ram_iterate) {
+        ret = f->hooks->after_ram_iterate(f, f->opaque, flags, NULL);
         if (ret < 0) {
             qemu_file_set_error(f, ret);
         }
@@ -173,8 +179,8 @@ void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data)
 {
     int ret = -EINVAL;
 
-    if (f->ops->hook_ram_load) {
-        ret = f->ops->hook_ram_load(f, f->opaque, flags, data);
+    if (f->hooks && f->hooks->hook_ram_load) {
+        ret = f->hooks->hook_ram_load(f, f->opaque, flags, data);
         if (ret < 0) {
             qemu_file_set_error(f, ret);
         }
@@ -193,9 +199,9 @@ size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset,
                              ram_addr_t offset, size_t size,
                              uint64_t *bytes_sent)
 {
-    if (f->ops->save_page) {
-        int ret = f->ops->save_page(f, f->opaque, block_offset,
-                                    offset, size, bytes_sent);
+    if (f->hooks && f->hooks->save_page) {
+        int ret = f->hooks->save_page(f, f->opaque, block_offset,
+                                      offset, size, bytes_sent);
 
         if (ret != RAM_SAVE_CONTROL_DELAYED) {
             if (bytes_sent && *bytes_sent > 0) {
diff --git a/migration/rdma.c b/migration/rdma.c
index bcae1e8..187fc1c 100644
--- a/migration/rdma.c
+++ b/migration/rdma.c
@@ -3378,12 +3378,18 @@ static const QEMUFileOps rdma_read_ops = {
     .get_buffer    = qemu_rdma_get_buffer,
     .get_fd        = qemu_rdma_get_fd,
     .close         = qemu_rdma_close,
+};
+
+static const QEMUFileHooks rdma_read_hooks = {
     .hook_ram_load = rdma_load_hook,
 };
 
 static const QEMUFileOps rdma_write_ops = {
     .put_buffer         = qemu_rdma_put_buffer,
     .close              = qemu_rdma_close,
+};
+
+static const QEMUFileHooks rdma_write_hooks = {
     .before_ram_iterate = qemu_rdma_registration_start,
     .after_ram_iterate  = qemu_rdma_registration_stop,
     .save_page          = qemu_rdma_save_page,
@@ -3402,8 +3408,10 @@ static void *qemu_fopen_rdma(RDMAContext *rdma, const char *mode)
 
     if (mode[0] == 'w') {
         r->file = qemu_fopen_ops(r, &rdma_write_ops);
+        qemu_file_set_hooks(r->file, &rdma_write_hooks);
     } else {
         r->file = qemu_fopen_ops(r, &rdma_read_ops);
+        qemu_file_set_hooks(r->file, &rdma_read_hooks);
     }
 
     return r->file;
-- 
2.5.0