[07/10] block: add x-blockdev-amend qmp command
diff mbox series

Message ID 20190830205608.18192-8-mlevitsk@redhat.com
State New
Headers show
Series
  • RFC crypto/luks: encryption key managment using amend interface
Related show

Commit Message

Maxim Levitsky Aug. 30, 2019, 8:56 p.m. UTC
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
---
 block/Makefile.objs       |   2 +-
 block/amend.c             | 116 ++++++++++++++++++++++++++++++++++++++
 include/block/block_int.h |  23 ++++++--
 qapi/block-core.json      |  26 +++++++++
 qapi/job.json             |   4 +-
 5 files changed, 163 insertions(+), 8 deletions(-)
 create mode 100644 block/amend.c

Patch
diff mbox series

diff --git a/block/Makefile.objs b/block/Makefile.objs
index 35f3bca4d9..10d0308792 100644
--- a/block/Makefile.objs
+++ b/block/Makefile.objs
@@ -18,7 +18,7 @@  block-obj-y += block-backend.o snapshot.o qapi.o
 block-obj-$(CONFIG_WIN32) += file-win32.o win32-aio.o
 block-obj-$(CONFIG_POSIX) += file-posix.o
 block-obj-$(CONFIG_LINUX_AIO) += linux-aio.o
-block-obj-y += null.o mirror.o commit.o io.o create.o
+block-obj-y += null.o mirror.o commit.o io.o create.o amend.o
 block-obj-y += throttle-groups.o
 block-obj-$(CONFIG_LINUX) += nvme.o
 
diff --git a/block/amend.c b/block/amend.c
new file mode 100644
index 0000000000..9bd28e08e7
--- /dev/null
+++ b/block/amend.c
@@ -0,0 +1,116 @@ 
+/*
+ * Block layer code related to image options amend
+ *
+ * Copyright (c) 2018 Kevin Wolf <kwolf@redhat.com>
+ * Copyright (c) 2019 Maxim Levitsky <mlevitsk@redhat.com>
+ *
+ * Heavily based on create.c
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu/osdep.h"
+#include "block/block_int.h"
+#include "qemu/job.h"
+#include "qemu/main-loop.h"
+#include "qapi/qapi-commands-block-core.h"
+#include "qapi/qapi-visit-block-core.h"
+#include "qapi/clone-visitor.h"
+#include "qapi/error.h"
+
+typedef struct BlockdevAmendJob {
+    Job common;
+    BlockdevCreateOptions *opts;
+    BlockDriverState *bs;
+    bool force;
+} BlockdevAmendJob;
+
+static int coroutine_fn blockdev_amend_run(Job *job, Error **errp)
+{
+    BlockdevAmendJob *s = container_of(job, BlockdevAmendJob, common);
+    int ret;
+
+    job_progress_set_remaining(&s->common, 1);
+    ret = s->bs->drv->bdrv_co_amend(s->bs, s->opts, s->force, errp);
+    job_progress_update(&s->common, 1);
+
+    qapi_free_BlockdevCreateOptions(s->opts);
+
+    return ret;
+}
+
+static const JobDriver blockdev_amend_job_driver = {
+    .instance_size = sizeof(BlockdevAmendJob),
+    .job_type      = JOB_TYPE_AMEND,
+    .run           = blockdev_amend_run,
+};
+
+void qmp_x_blockdev_amend(const char *job_id,
+                        const char *node_name,
+                        BlockdevCreateOptions *options,
+                        bool has_force,
+                        bool force,
+                        Error **errp)
+{
+    BlockdevAmendJob *s;
+    const char *fmt = BlockdevDriver_str(options->driver);
+    BlockDriver *drv = bdrv_find_format(fmt);
+    BlockDriverState *bs = bdrv_find_node(node_name);
+
+    /*
+     * If the driver is in the schema, we know that it exists. But it may not
+     * be whitelisted.
+     */
+    assert(drv);
+    if (bdrv_uses_whitelist() && !bdrv_is_whitelisted(drv, false)) {
+        error_setg(errp, "Driver is not whitelisted");
+        return;
+    }
+
+    if (bs->drv != drv) {
+        error_setg(errp,
+                   "x-blockdev-amend doesn't support changing the block driver");
+        return;
+
+    }
+
+    /* Error out if the driver doesn't support .bdrv_co_amend */
+    if (!drv->bdrv_co_amend) {
+        error_setg(errp, "Driver does not support x-blockdev-amend");
+        return;
+    }
+
+    /*
+     * Create the block job
+     * TODO Running in the main context. Block drivers need to error out or add
+     * locking when they use a BDS in a different AioContext.
+     */
+    s = job_create(job_id, &blockdev_amend_job_driver, NULL,
+                   qemu_get_aio_context(), JOB_DEFAULT | JOB_MANUAL_DISMISS,
+                   NULL, NULL, errp);
+    if (!s) {
+        return;
+    }
+
+    s->bs = bs,
+    s->opts = QAPI_CLONE(BlockdevCreateOptions, options),
+    s->force = has_force ? force : false;
+
+    job_start(&s->common);
+}
diff --git a/include/block/block_int.h b/include/block/block_int.h
index c6aa05214f..546c84957c 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -133,11 +133,28 @@  struct BlockDriver {
     int (*bdrv_file_open)(BlockDriverState *bs, QDict *options, int flags,
                           Error **errp);
     void (*bdrv_close)(BlockDriverState *bs);
+
+
     int coroutine_fn (*bdrv_co_create)(BlockdevCreateOptions *opts,
                                        Error **errp);
     int coroutine_fn (*bdrv_co_create_opts)(const char *filename,
                                             QemuOpts *opts,
                                             Error **errp);
+
+
+    int coroutine_fn (*bdrv_co_amend)(BlockDriverState *bs,
+                                      BlockdevCreateOptions *opts,
+                                      bool force,
+                                      Error **errp);
+
+    int (*bdrv_amend_options)(BlockDriverState *bs,
+                              QemuOpts *opts,
+                              BlockDriverAmendStatusCB *status_cb,
+                              void *cb_opaque,
+                              bool force,
+                              Error **errp);
+
+
     int (*bdrv_make_empty)(BlockDriverState *bs);
 
     /*
@@ -399,12 +416,6 @@  struct BlockDriver {
                                       BdrvCheckResult *result,
                                       BdrvCheckMode fix);
 
-    int (*bdrv_amend_options)(BlockDriverState *bs, QemuOpts *opts,
-                              BlockDriverAmendStatusCB *status_cb,
-                              void *cb_opaque,
-                              bool force,
-                              Error **errp);
-
     void (*bdrv_debug_event)(BlockDriverState *bs, BlkdebugEvent event);
 
     /* TODO Better pass a option string/QDict/QemuOpts to add any rule? */
diff --git a/qapi/block-core.json b/qapi/block-core.json
index e6edd641f1..7900914506 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -4650,6 +4650,32 @@ 
   'data': { 'job-id': 'str',
             'options': 'BlockdevCreateOptions' } }
 
+##
+# @x-blockdev-amend:
+#
+# Starts a job to amend format specific options of an existing open block device.
+# The job is automatically finalized, but a manual job-dismiss is required.
+#
+# @job-id:          Identifier for the newly created job.
+#
+# @node-name:       Name of the block node to work on
+#
+# @options:         Options (same as for image creation)
+#
+# @force:           Allow unsafe operations, format specific
+#                   For luks that allows erase of the last active keyslot
+#                   (permanent loss of data),
+#                   and replacement of an active keyslot
+#                   (possible loss of data if IO error happens)
+#
+# Since: 4.2
+##
+{ 'command': 'x-blockdev-amend',
+  'data': { 'job-id': 'str',
+            'node-name': 'str',
+            'options': 'BlockdevCreateOptions',
+            '*force': 'bool' } }
+
 ##
 # @blockdev-open-tray:
 #
diff --git a/qapi/job.json b/qapi/job.json
index a121b615fb..342d29a7aa 100644
--- a/qapi/job.json
+++ b/qapi/job.json
@@ -19,10 +19,12 @@ 
 #
 # @create: image creation job type, see "blockdev-create" (since 3.0)
 #
+# @amend: image options amend job type, see "x-blockdev-amend" (since 4.2)
+#
 # Since: 1.7
 ##
 { 'enum': 'JobType',
-  'data': ['commit', 'stream', 'mirror', 'backup', 'create'] }
+  'data': ['commit', 'stream', 'mirror', 'backup', 'create', 'amend'] }
 
 ##
 # @JobStatus: