xref: /qemu/block/amend.c (revision 29b62a10) 
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-io.h"
30 #include "block/block_int.h"
31 #include "qemu/job.h"
32 #include "qemu/main-loop.h"
33 #include "qapi/qapi-commands-block-core.h"
34 #include "qapi/qapi-visit-block-core.h"
35 #include "qapi/clone-visitor.h"
36 #include "qapi/error.h"
37 
38 typedef struct BlockdevAmendJob {
39     Job common;
40     BlockdevAmendOptions *opts;
41     BlockDriverState *bs;
42     bool force;
43 } BlockdevAmendJob;
44 
45 static int coroutine_fn blockdev_amend_run(Job *job, Error **errp)
46 {
47     BlockdevAmendJob *s = container_of(job, BlockdevAmendJob, common);
48     int ret;
49 
50     job_progress_set_remaining(&s->common, 1);
51     ret = s->bs->drv->bdrv_co_amend(s->bs, s->opts, s->force, errp);
52     job_progress_update(&s->common, 1);
53     qapi_free_BlockdevAmendOptions(s->opts);
54     return ret;
55 }
56 
57 static int blockdev_amend_pre_run(BlockdevAmendJob *s, Error **errp)
58 {
59     if (s->bs->drv->bdrv_amend_pre_run) {
60         return s->bs->drv->bdrv_amend_pre_run(s->bs, errp);
61     }
62 
63     return 0;
64 }
65 
66 static void blockdev_amend_free(Job *job)
67 {
68     BlockdevAmendJob *s = container_of(job, BlockdevAmendJob, common);
69 
70     if (s->bs->drv->bdrv_amend_clean) {
71         s->bs->drv->bdrv_amend_clean(s->bs);
72     }
73 
74     bdrv_unref(s->bs);
75 }
76 
77 static const JobDriver blockdev_amend_job_driver = {
78     .instance_size = sizeof(BlockdevAmendJob),
79     .job_type      = JOB_TYPE_AMEND,
80     .run           = blockdev_amend_run,
81     .free          = blockdev_amend_free,
82 };
83 
84 void qmp_x_blockdev_amend(const char *job_id,
85                           const char *node_name,
86                           BlockdevAmendOptions *options,
87                           bool has_force,
88                           bool force,
89                           Error **errp)
90 {
91     BlockdevAmendJob *s;
92     const char *fmt = BlockdevDriver_str(options->driver);
93     BlockDriver *drv = bdrv_find_format(fmt);
94     BlockDriverState *bs;
95 
96     bs = bdrv_lookup_bs(NULL, node_name, errp);
97     if (!bs) {
98         return;
99     }
100 
101     if (!drv) {
102         error_setg(errp, "Block driver '%s' not found or not supported", fmt);
103         return;
104     }
105 
106     /*
107      * If the driver is in the schema, we know that it exists. But it may not
108      * be whitelisted.
109      */
110     if (bdrv_uses_whitelist() && !bdrv_is_whitelisted(drv, false)) {
111         error_setg(errp, "Driver is not whitelisted");
112         return;
113     }
114 
115     if (bs->drv != drv) {
116         error_setg(errp,
117                    "x-blockdev-amend doesn't support changing the block driver");
118         return;
119     }
120 
121     /* Error out if the driver doesn't support .bdrv_co_amend */
122     if (!drv->bdrv_co_amend) {
123         error_setg(errp, "Driver does not support x-blockdev-amend");
124         return;
125     }
126 
127     /* Create the block job */
128     s = job_create(job_id, &blockdev_amend_job_driver, NULL,
129                    bdrv_get_aio_context(bs), JOB_DEFAULT | JOB_MANUAL_DISMISS,
130                    NULL, NULL, errp);
131     if (!s) {
132         return;
133     }
134 
135     bdrv_ref(bs);
136     s->bs = bs,
137     s->opts = QAPI_CLONE(BlockdevAmendOptions, options),
138     s->force = has_force ? force : false;
139 
140     if (blockdev_amend_pre_run(s, errp)) {
141         job_early_fail(&s->common);
142         return;
143     }
144 
145     job_start(&s->common);
146 }
147