blockdev: 'blockdev-add' QMP command

[qemu.git] / blockdev.c

diff --git a/blockdev.c b/blockdev.c
index 8c83f6f1cab336d9aecf48ee8b516758f92cfdb6..9929d781a55bced2ef9b285c62f7eea29cbb2002 100644 (file)
--- a/blockdev.c
+++ b/blockdev.c
@@ -38,6 +38,8 @@
 #include "qemu/option.h"
 #include "qemu/config-file.h"
 #include "qapi/qmp/types.h"
+#include "qapi-visit.h"
+#include "qapi/qmp-output-visitor.h"
 #include "sysemu/sysemu.h"
 #include "block/block_int.h"
 #include "qmp-commands.h"
@@ -89,6 +91,10 @@ void blockdev_mark_auto_del(BlockDriverState *bs)
 {
     DriveInfo *dinfo = drive_get_by_blockdev(bs);
 
+    if (dinfo && !dinfo->enable_auto_del) {
+        return;
+    }
+
     if (bs->job) {
         block_job_cancel(bs->job);
     }
@@ -468,13 +474,9 @@ static DriveInfo *blockdev_init(QemuOpts *all_opts,
             return NULL;
         }
 
-        drv = bdrv_find_whitelisted_format(buf, ro);
+        drv = bdrv_find_format(buf);
         if (!drv) {
-            if (!ro && bdrv_find_whitelisted_format(buf, !ro)) {
-                error_report("'%s' can be only used as read-only device.", buf);
-            } else {
-                error_report("'%s' invalid format", buf);
-            }
+            error_report("'%s' invalid format", buf);
             return NULL;
         }
     }
@@ -750,6 +752,7 @@ static void qemu_opt_rename(QemuOpts *opts, const char *from, const char *to)
 DriveInfo *drive_init(QemuOpts *all_opts, BlockInterfaceType block_default_type)
 {
     const char *value;
+    DriveInfo *dinfo;
 
     /* Change legacy command line options into QMP ones */
     qemu_opt_rename(all_opts, "iops", "throttling.iops-total");
@@ -798,7 +801,17 @@ DriveInfo *drive_init(QemuOpts *all_opts, BlockInterfaceType block_default_type)
         qemu_opt_unset(all_opts, "cache");
     }
 
-    return blockdev_init(all_opts, block_default_type);
+    /* Actual block device init: Functionality shared with blockdev-add */
+    dinfo = blockdev_init(all_opts, block_default_type);
+    if (dinfo == NULL) {
+        goto fail;
+    }
+
+    /* Set legacy DriveInfo fields */
+    dinfo->enable_auto_del = true;
+
+fail:
+    return dinfo;
 }
 
 void do_commit(Monitor *mon, const QDict *qdict)
@@ -1131,6 +1144,11 @@ static void external_snapshot_prepare(BlkTransactionState *common,
         }
     }
 
+    if (bdrv_check_ext_snapshot(state->old_bs) != EXT_SNAPSHOT_ALLOWED) {
+        error_set(errp, QERR_FEATURE_DISABLED, "snapshot");
+        return;
+    }
+
     flags = state->old_bs->open_flags;
 
     /* create new image w/backing file */
@@ -2050,6 +2068,61 @@ void qmp_block_job_complete(const char *device, Error **errp)
     block_job_complete(job, errp);
 }
 
+void qmp_blockdev_add(BlockdevOptions *options, Error **errp)
+{
+    QmpOutputVisitor *ov = qmp_output_visitor_new();
+    QObject *obj;
+    QDict *qdict;
+    DriveInfo *dinfo;
+    Error *local_err = NULL;
+
+    /* Require an ID in the top level */
+    if (!options->has_id) {
+        error_setg(errp, "Block device needs an ID");
+        goto fail;
+    }
+
+    /* TODO Sort it out in raw-posix and drive_init: Reject aio=native with
+     * cache.direct=false instead of silently switching to aio=threads, except
+     * if called from drive_init.
+     *
+     * For now, simply forbidding the combination for all drivers will do. */
+    if (options->has_aio && options->aio == BLOCKDEV_AIO_OPTIONS_NATIVE) {
+        bool direct = options->cache->has_direct && options->cache->direct;
+        if (!options->has_cache && !direct) {
+            error_setg(errp, "aio=native requires cache.direct=true");
+            goto fail;
+        }
+    }
+
+    visit_type_BlockdevOptions(qmp_output_get_visitor(ov),
+                               &options, NULL, &local_err);
+    if (error_is_set(&local_err)) {
+        error_propagate(errp, local_err);
+        goto fail;
+    }
+
+    obj = qmp_output_get_qobject(ov);
+    qdict = qobject_to_qdict(obj);
+
+    qdict_flatten(qdict);
+
+    QemuOpts *opts = qemu_opts_from_qdict(&qemu_drive_opts, qdict, &local_err);
+    if (error_is_set(&local_err)) {
+        error_propagate(errp, local_err);
+        goto fail;
+    }
+
+    dinfo = blockdev_init(opts, IF_NONE);
+    if (!dinfo) {
+        error_setg(errp, "Could not open image");
+        goto fail;
+    }
+
+fail:
+    qmp_output_visitor_cleanup(ov);
+}
+
 static void do_qmp_query_block_jobs_one(void *opaque, BlockDriverState *bs)
 {
     BlockJobInfoList **prev = opaque;