[Qemu-devel] [PATCH v2 02/18] drive-backup: create do_backup_common

[John Snow]

Create a common core that comprises the actual meat of what the backup API
boundary needs to do, and then switch drive-backup to use it.

Questions:
 - do_drive_backup now acquires and releases the aio_context in addition
   to do_backup_common doing the same. Can I drop this from drive_backup?
Signed-off-by: John Snow <address@hidden>
---
 blockdev.c | 138 ++++++++++++++++++++++++++++++++---------------------
 1 file changed, 83 insertions(+), 55 deletions(-)

diff --git a/blockdev.c b/blockdev.c
index 4d141e9a1f..5fd663a7e5 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -3425,6 +3425,86 @@ out:
     aio_context_release(aio_context);
 }
 
+static BlockJob *do_backup_common(BackupCommon *backup,
+                                  BlockDriverState *target_bs,
+                                  JobTxn *txn, Error **errp)
+{
+    BlockDriverState *bs;
+    BlockJob *job = NULL;
+    BdrvDirtyBitmap *bmap = NULL;
+    AioContext *aio_context;
+    Error *local_err = NULL;
+    int job_flags = JOB_DEFAULT;
+    int ret;
+
+    if (!backup->has_speed) {
+        backup->speed = 0;
+    }
+    if (!backup->has_on_source_error) {
+        backup->on_source_error = BLOCKDEV_ON_ERROR_REPORT;
+    }
+    if (!backup->has_on_target_error) {
+        backup->on_target_error = BLOCKDEV_ON_ERROR_REPORT;
+    }
+    if (!backup->has_job_id) {
+        backup->job_id = NULL;
+    }
+    if (!backup->has_auto_finalize) {
+        backup->auto_finalize = true;
+    }
+    if (!backup->has_auto_dismiss) {
+        backup->auto_dismiss = true;
+    }
+    if (!backup->has_compress) {
+        backup->compress = false;
+    }
+
+    bs = bdrv_lookup_bs(backup->device, backup->device, errp);
+    if (!bs) {
+        return NULL;
+    }
+
+    aio_context = bdrv_get_aio_context(bs);
+    aio_context_acquire(aio_context);
+
+    ret = bdrv_try_set_aio_context(target_bs, aio_context, errp);
+    if (ret < 0) {
+        bdrv_unref(target_bs);
+        goto out;
+    }
+
+    if (backup->has_bitmap) {
+        bmap = bdrv_find_dirty_bitmap(bs, backup->bitmap);
+        if (!bmap) {
+            error_setg(errp, "Bitmap '%s' could not be found", backup->bitmap);
+            goto out;
+        }
+        if (bdrv_dirty_bitmap_check(bmap, BDRV_BITMAP_DEFAULT, errp)) {
+            goto out;
+        }
+    }
+
+    if (!backup->auto_finalize) {
+        job_flags |= JOB_MANUAL_FINALIZE;
+    }
+    if (!backup->auto_dismiss) {
+        job_flags |= JOB_MANUAL_DISMISS;
+    }
+
+    job = backup_job_create(backup->job_id, bs, target_bs, backup->speed,
+                            backup->sync, bmap, backup->compress,
+                            backup->on_source_error, backup->on_target_error,
+                            job_flags, NULL, NULL, txn, &local_err);
+    if (local_err != NULL) {
+        error_propagate(errp, local_err);
+        goto out;
+    }
+
+out:
+    aio_context_release(aio_context);
+    return job;
+}
+
 static BlockJob *do_drive_backup(DriveBackup *backup, JobTxn *txn,
                                  Error **errp)
 {
@@ -3432,39 +3512,16 @@ static BlockJob *do_drive_backup(DriveBackup *backup, 
JobTxn *txn,
     BlockDriverState *target_bs;
     BlockDriverState *source = NULL;
     BlockJob *job = NULL;
-    BdrvDirtyBitmap *bmap = NULL;
     AioContext *aio_context;
     QDict *options = NULL;
     Error *local_err = NULL;
-    int flags, job_flags = JOB_DEFAULT;
+    int flags;
     int64_t size;
     bool set_backing_hd = false;
-    int ret;
 
-    if (!backup->has_speed) {
-        backup->speed = 0;
-    }
-    if (!backup->has_on_source_error) {
-        backup->on_source_error = BLOCKDEV_ON_ERROR_REPORT;
-    }
-    if (!backup->has_on_target_error) {
-        backup->on_target_error = BLOCKDEV_ON_ERROR_REPORT;
-    }
     if (!backup->has_mode) {
         backup->mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
     }
-    if (!backup->has_job_id) {
-        backup->job_id = NULL;
-    }
-    if (!backup->has_auto_finalize) {
-        backup->auto_finalize = true;
-    }
-    if (!backup->has_auto_dismiss) {
-        backup->auto_dismiss = true;
-    }
-    if (!backup->has_compress) {
-        backup->compress = false;
-    }
 
     bs = bdrv_lookup_bs(backup->device, backup->device, errp);
     if (!bs) {
@@ -3541,12 +3598,6 @@ static BlockJob *do_drive_backup(DriveBackup *backup, 
JobTxn *txn,
         goto out;
     }
 
-    ret = bdrv_try_set_aio_context(target_bs, aio_context, errp);
-    if (ret < 0) {
-        bdrv_unref(target_bs);
-        goto out;
-    }
-
     if (set_backing_hd) {
         bdrv_set_backing_hd(target_bs, source, &local_err);
         if (local_err) {
@@ -3554,31 +3605,8 @@ static BlockJob *do_drive_backup(DriveBackup *backup, 
JobTxn *txn,
         }
     }
 
-    if (backup->has_bitmap) {
-        bmap = bdrv_find_dirty_bitmap(bs, backup->bitmap);
-        if (!bmap) {
-            error_setg(errp, "Bitmap '%s' could not be found", backup->bitmap);
-            goto unref;
-        }
-        if (bdrv_dirty_bitmap_check(bmap, BDRV_BITMAP_DEFAULT, errp)) {
-            goto unref;
-        }
-    }
-    if (!backup->auto_finalize) {
-        job_flags |= JOB_MANUAL_FINALIZE;
-    }
-    if (!backup->auto_dismiss) {
-        job_flags |= JOB_MANUAL_DISMISS;
-    }
-
-    job = backup_job_create(backup->job_id, bs, target_bs, backup->speed,
-                            backup->sync, bmap, backup->compress,
-                            backup->on_source_error, backup->on_target_error,
-                            job_flags, NULL, NULL, txn, &local_err);
-    if (local_err != NULL) {
-        error_propagate(errp, local_err);
-        goto unref;
-    }
+    job = do_backup_common(qapi_DriveBackup_base(backup),
+                           target_bs, txn, errp);
 
 unref:
     bdrv_unref(target_bs);
-- 
2.21.0