s390x/sclpconsole-lm: Fix hanging SCLP line mode console
[qemu.git] / blockjob.c
1 /*
2 * QEMU System Emulator block driver
3 *
4 * Copyright (c) 2011 IBM Corp.
5 * Copyright (c) 2012 Red Hat, Inc.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a copy
8 * of this software and associated documentation files (the "Software"), to deal
9 * in the Software without restriction, including without limitation the rights
10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11 * copies of the Software, and to permit persons to whom the Software is
12 * furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included in
15 * all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23 * THE SOFTWARE.
24 */
25
26 #include "config-host.h"
27 #include "qemu-common.h"
28 #include "trace.h"
29 #include "block/block.h"
30 #include "block/blockjob.h"
31 #include "block/block_int.h"
32 #include "qapi/qmp/qjson.h"
33 #include "block/coroutine.h"
34 #include "qmp-commands.h"
35 #include "qemu/timer.h"
36 #include "qapi-event.h"
37
38 void *block_job_create(const BlockJobDriver *driver, BlockDriverState *bs,
39 int64_t speed, BlockCompletionFunc *cb,
40 void *opaque, Error **errp)
41 {
42 BlockJob *job;
43
44 if (bs->job) {
45 error_set(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
46 return NULL;
47 }
48 bdrv_ref(bs);
49 job = g_malloc0(driver->instance_size);
50 error_setg(&job->blocker, "block device is in use by block job: %s",
51 BlockJobType_lookup[driver->job_type]);
52 bdrv_op_block_all(bs, job->blocker);
53 bdrv_op_unblock(bs, BLOCK_OP_TYPE_DATAPLANE, job->blocker);
54
55 job->driver = driver;
56 job->bs = bs;
57 job->cb = cb;
58 job->opaque = opaque;
59 job->busy = true;
60 bs->job = job;
61
62 /* Only set speed when necessary to avoid NotSupported error */
63 if (speed != 0) {
64 Error *local_err = NULL;
65
66 block_job_set_speed(job, speed, &local_err);
67 if (local_err) {
68 bs->job = NULL;
69 bdrv_op_unblock_all(bs, job->blocker);
70 error_free(job->blocker);
71 g_free(job);
72 error_propagate(errp, local_err);
73 return NULL;
74 }
75 }
76 return job;
77 }
78
79 void block_job_completed(BlockJob *job, int ret)
80 {
81 BlockDriverState *bs = job->bs;
82
83 assert(bs->job == job);
84 job->cb(job->opaque, ret);
85 bs->job = NULL;
86 bdrv_op_unblock_all(bs, job->blocker);
87 error_free(job->blocker);
88 g_free(job);
89 }
90
91 void block_job_set_speed(BlockJob *job, int64_t speed, Error **errp)
92 {
93 Error *local_err = NULL;
94
95 if (!job->driver->set_speed) {
96 error_set(errp, QERR_UNSUPPORTED);
97 return;
98 }
99 job->driver->set_speed(job, speed, &local_err);
100 if (local_err) {
101 error_propagate(errp, local_err);
102 return;
103 }
104
105 job->speed = speed;
106 }
107
108 void block_job_complete(BlockJob *job, Error **errp)
109 {
110 if (job->paused || job->cancelled || !job->driver->complete) {
111 error_set(errp, QERR_BLOCK_JOB_NOT_READY,
112 bdrv_get_device_name(job->bs));
113 return;
114 }
115
116 job->driver->complete(job, errp);
117 }
118
119 void block_job_pause(BlockJob *job)
120 {
121 job->paused = true;
122 }
123
124 bool block_job_is_paused(BlockJob *job)
125 {
126 return job->paused;
127 }
128
129 void block_job_resume(BlockJob *job)
130 {
131 job->paused = false;
132 block_job_iostatus_reset(job);
133 if (job->co && !job->busy) {
134 qemu_coroutine_enter(job->co, NULL);
135 }
136 }
137
138 void block_job_cancel(BlockJob *job)
139 {
140 job->cancelled = true;
141 block_job_resume(job);
142 }
143
144 bool block_job_is_cancelled(BlockJob *job)
145 {
146 return job->cancelled;
147 }
148
149 void block_job_iostatus_reset(BlockJob *job)
150 {
151 job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
152 if (job->driver->iostatus_reset) {
153 job->driver->iostatus_reset(job);
154 }
155 }
156
157 struct BlockFinishData {
158 BlockJob *job;
159 BlockCompletionFunc *cb;
160 void *opaque;
161 bool cancelled;
162 int ret;
163 };
164
165 static void block_job_finish_cb(void *opaque, int ret)
166 {
167 struct BlockFinishData *data = opaque;
168
169 data->cancelled = block_job_is_cancelled(data->job);
170 data->ret = ret;
171 data->cb(data->opaque, ret);
172 }
173
174 static int block_job_finish_sync(BlockJob *job,
175 void (*finish)(BlockJob *, Error **errp),
176 Error **errp)
177 {
178 struct BlockFinishData data;
179 BlockDriverState *bs = job->bs;
180 Error *local_err = NULL;
181
182 assert(bs->job == job);
183
184 /* Set up our own callback to store the result and chain to
185 * the original callback.
186 */
187 data.job = job;
188 data.cb = job->cb;
189 data.opaque = job->opaque;
190 data.ret = -EINPROGRESS;
191 job->cb = block_job_finish_cb;
192 job->opaque = &data;
193 finish(job, &local_err);
194 if (local_err) {
195 error_propagate(errp, local_err);
196 return -EBUSY;
197 }
198 while (data.ret == -EINPROGRESS) {
199 aio_poll(bdrv_get_aio_context(bs), true);
200 }
201 return (data.cancelled && data.ret == 0) ? -ECANCELED : data.ret;
202 }
203
204 /* A wrapper around block_job_cancel() taking an Error ** parameter so it may be
205 * used with block_job_finish_sync() without the need for (rather nasty)
206 * function pointer casts there. */
207 static void block_job_cancel_err(BlockJob *job, Error **errp)
208 {
209 block_job_cancel(job);
210 }
211
212 int block_job_cancel_sync(BlockJob *job)
213 {
214 return block_job_finish_sync(job, &block_job_cancel_err, NULL);
215 }
216
217 int block_job_complete_sync(BlockJob *job, Error **errp)
218 {
219 return block_job_finish_sync(job, &block_job_complete, errp);
220 }
221
222 void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns)
223 {
224 assert(job->busy);
225
226 /* Check cancellation *before* setting busy = false, too! */
227 if (block_job_is_cancelled(job)) {
228 return;
229 }
230
231 job->busy = false;
232 if (block_job_is_paused(job)) {
233 qemu_coroutine_yield();
234 } else {
235 co_aio_sleep_ns(bdrv_get_aio_context(job->bs), type, ns);
236 }
237 job->busy = true;
238 }
239
240 void block_job_yield(BlockJob *job)
241 {
242 assert(job->busy);
243
244 /* Check cancellation *before* setting busy = false, too! */
245 if (block_job_is_cancelled(job)) {
246 return;
247 }
248
249 job->busy = false;
250 qemu_coroutine_yield();
251 job->busy = true;
252 }
253
254 BlockJobInfo *block_job_query(BlockJob *job)
255 {
256 BlockJobInfo *info = g_new0(BlockJobInfo, 1);
257 info->type = g_strdup(BlockJobType_lookup[job->driver->job_type]);
258 info->device = g_strdup(bdrv_get_device_name(job->bs));
259 info->len = job->len;
260 info->busy = job->busy;
261 info->paused = job->paused;
262 info->offset = job->offset;
263 info->speed = job->speed;
264 info->io_status = job->iostatus;
265 info->ready = job->ready;
266 return info;
267 }
268
269 static void block_job_iostatus_set_err(BlockJob *job, int error)
270 {
271 if (job->iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
272 job->iostatus = error == ENOSPC ? BLOCK_DEVICE_IO_STATUS_NOSPACE :
273 BLOCK_DEVICE_IO_STATUS_FAILED;
274 }
275 }
276
277 void block_job_event_cancelled(BlockJob *job)
278 {
279 qapi_event_send_block_job_cancelled(job->driver->job_type,
280 bdrv_get_device_name(job->bs),
281 job->len,
282 job->offset,
283 job->speed,
284 &error_abort);
285 }
286
287 void block_job_event_completed(BlockJob *job, const char *msg)
288 {
289 qapi_event_send_block_job_completed(job->driver->job_type,
290 bdrv_get_device_name(job->bs),
291 job->len,
292 job->offset,
293 job->speed,
294 !!msg,
295 msg,
296 &error_abort);
297 }
298
299 void block_job_event_ready(BlockJob *job)
300 {
301 job->ready = true;
302
303 qapi_event_send_block_job_ready(job->driver->job_type,
304 bdrv_get_device_name(job->bs),
305 job->len,
306 job->offset,
307 job->speed, &error_abort);
308 }
309
310 BlockErrorAction block_job_error_action(BlockJob *job, BlockDriverState *bs,
311 BlockdevOnError on_err,
312 int is_read, int error)
313 {
314 BlockErrorAction action;
315
316 switch (on_err) {
317 case BLOCKDEV_ON_ERROR_ENOSPC:
318 action = (error == ENOSPC) ?
319 BLOCK_ERROR_ACTION_STOP : BLOCK_ERROR_ACTION_REPORT;
320 break;
321 case BLOCKDEV_ON_ERROR_STOP:
322 action = BLOCK_ERROR_ACTION_STOP;
323 break;
324 case BLOCKDEV_ON_ERROR_REPORT:
325 action = BLOCK_ERROR_ACTION_REPORT;
326 break;
327 case BLOCKDEV_ON_ERROR_IGNORE:
328 action = BLOCK_ERROR_ACTION_IGNORE;
329 break;
330 default:
331 abort();
332 }
333 qapi_event_send_block_job_error(bdrv_get_device_name(job->bs),
334 is_read ? IO_OPERATION_TYPE_READ :
335 IO_OPERATION_TYPE_WRITE,
336 action, &error_abort);
337 if (action == BLOCK_ERROR_ACTION_STOP) {
338 block_job_pause(job);
339 block_job_iostatus_set_err(job, error);
340 if (bs != job->bs) {
341 bdrv_iostatus_set_err(bs, error);
342 }
343 }
344 return action;
345 }
346
347 typedef struct {
348 BlockJob *job;
349 QEMUBH *bh;
350 AioContext *aio_context;
351 BlockJobDeferToMainLoopFn *fn;
352 void *opaque;
353 } BlockJobDeferToMainLoopData;
354
355 static void block_job_defer_to_main_loop_bh(void *opaque)
356 {
357 BlockJobDeferToMainLoopData *data = opaque;
358 AioContext *aio_context;
359
360 qemu_bh_delete(data->bh);
361
362 /* Prevent race with block_job_defer_to_main_loop() */
363 aio_context_acquire(data->aio_context);
364
365 /* Fetch BDS AioContext again, in case it has changed */
366 aio_context = bdrv_get_aio_context(data->job->bs);
367 aio_context_acquire(aio_context);
368
369 data->fn(data->job, data->opaque);
370
371 aio_context_release(aio_context);
372
373 aio_context_release(data->aio_context);
374
375 g_free(data);
376 }
377
378 void block_job_defer_to_main_loop(BlockJob *job,
379 BlockJobDeferToMainLoopFn *fn,
380 void *opaque)
381 {
382 BlockJobDeferToMainLoopData *data = g_malloc(sizeof(*data));
383 data->job = job;
384 data->bh = qemu_bh_new(block_job_defer_to_main_loop_bh, data);
385 data->aio_context = bdrv_get_aio_context(job->bs);
386 data->fn = fn;
387 data->opaque = opaque;
388
389 qemu_bh_schedule(data->bh);
390 }