xref: /qemu/block/amend.c (revision b2a3cbb8) 
1 /*
2  * Block layer code related to image options amend
3  *
4  * Copyright (c) 2018 Kevin Wolf <kwolf@redhat.com>
5  * Copyright (c) 2020 Red Hat. Inc
6  *
7  * Heavily based on create.c
8  *
9  * Permission is hereby granted, free of charge, to any person obtaining a copy
10  * of this software and associated documentation files (the "Software"), to deal
11  * in the Software without restriction, including without limitation the rights
12  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
13  * copies of the Software, and to permit persons to whom the Software is
14  * furnished to do so, subject to the following conditions:
15  *
16  * The above copyright notice and this permission notice shall be included in
17  * all copies or substantial portions of the Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
22  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
23  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
24  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
25  * THE SOFTWARE.
26  */
27 
28 #include "qemu/osdep.h"
29 #include "block/block_int.h"
30 #include "qemu/job.h"
31 #include "qemu/main-loop.h"
32 #include "qapi/qapi-commands-block-core.h"
33 #include "qapi/qapi-visit-block-core.h"
34 #include "qapi/clone-visitor.h"
35 #include "qapi/error.h"
36 
37 typedef struct BlockdevAmendJob {
38     Job common;
39     BlockdevAmendOptions *opts;
40     BlockDriverState *bs;
41     bool force;
42 } BlockdevAmendJob;
43 
44 static int coroutine_fn blockdev_amend_run(Job *job, Error **errp)
45 {
46     BlockdevAmendJob *s = container_of(job, BlockdevAmendJob, common);
47     int ret;
48 
49     job_progress_set_remaining(&s->common, 1);
50     ret = s->bs->drv->bdrv_co_amend(s->bs, s->opts, s->force, errp);
51     job_progress_update(&s->common, 1);
52     qapi_free_BlockdevAmendOptions(s->opts);
53     return ret;
54 }
55 
56 static int blockdev_amend_pre_run(BlockdevAmendJob *s, Error **errp)
57 {
58     if (s->bs->drv->bdrv_amend_pre_run) {
59         return s->bs->drv->bdrv_amend_pre_run(s->bs, errp);
60     }
61 
62     return 0;
63 }
64 
65 static void blockdev_amend_free(Job *job)
66 {
67     BlockdevAmendJob *s = container_of(job, BlockdevAmendJob, common);
68 
69     if (s->bs->drv->bdrv_amend_clean) {
70         s->bs->drv->bdrv_amend_clean(s->bs);
71     }
72 
73     bdrv_unref(s->bs);
74 }
75 
76 static const JobDriver blockdev_amend_job_driver = {
77     .instance_size = sizeof(BlockdevAmendJob),
78     .job_type      = JOB_TYPE_AMEND,
79     .run           = blockdev_amend_run,
80     .free          = blockdev_amend_free,
81 };
82 
83 void qmp_x_blockdev_amend(const char *job_id,
84                           const char *node_name,
85                           BlockdevAmendOptions *options,
86                           bool has_force,
87                           bool force,
88                           Error **errp)
89 {
90     BlockdevAmendJob *s;
91     const char *fmt = BlockdevDriver_str(options->driver);
92     BlockDriver *drv = bdrv_find_format(fmt);
93     BlockDriverState *bs;
94 
95     bs = bdrv_lookup_bs(NULL, node_name, errp);
96     if (!bs) {
97         return;
98     }
99 
100     if (!drv) {
101         error_setg(errp, "Block driver '%s' not found or not supported", fmt);
102         return;
103     }
104 
105     /*
106      * If the driver is in the schema, we know that it exists. But it may not
107      * be whitelisted.
108      */
109     if (bdrv_uses_whitelist() && !bdrv_is_whitelisted(drv, false)) {
110         error_setg(errp, "Driver is not whitelisted");
111         return;
112     }
113 
114     if (bs->drv != drv) {
115         error_setg(errp,
116                    "x-blockdev-amend doesn't support changing the block driver");
117         return;
118     }
119 
120     /* Error out if the driver doesn't support .bdrv_co_amend */
121     if (!drv->bdrv_co_amend) {
122         error_setg(errp, "Driver does not support x-blockdev-amend");
123         return;
124     }
125 
126     /* Create the block job */
127     s = job_create(job_id, &blockdev_amend_job_driver, NULL,
128                    bdrv_get_aio_context(bs), JOB_DEFAULT | JOB_MANUAL_DISMISS,
129                    NULL, NULL, errp);
130     if (!s) {
131         return;
132     }
133 
134     bdrv_ref(bs);
135     s->bs = bs,
136     s->opts = QAPI_CLONE(BlockdevAmendOptions, options),
137     s->force = has_force ? force : false;
138 
139     if (blockdev_amend_pre_run(s, errp)) {
140         job_early_fail(&s->common);
141         return;
142     }
143 
144     job_start(&s->common);
145 }
146