--- /dev/null
+/*
+ * QEMU System Emulator block driver
+ *
+ * Copyright (c) 2011 IBM Corp.
+ * Copyright (c) 2012 Red Hat, Inc.
+ *
+ * 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 "config-host.h"
+#include "qemu-common.h"
+#include "trace.h"
+#include "block/block.h"
+#include "block/blockjob.h"
+#include "block/block_int.h"
+#include "qapi/qmp/qerror.h"
+#include "qapi/qmp/qjson.h"
+#include "block/coroutine.h"
+#include "qmp-commands.h"
+#include "qemu/timer.h"
+#include "qapi-event.h"
+
+void *block_job_create(const BlockJobDriver *driver, BlockDriverState *bs,
+ int64_t speed, BlockCompletionFunc *cb,
+ void *opaque, Error **errp)
+{
+ BlockJob *job;
+
+ if (bs->job) {
+ error_setg(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
+ return NULL;
+ }
+ bdrv_ref(bs);
+ job = g_malloc0(driver->instance_size);
+ error_setg(&job->blocker, "block device is in use by block job: %s",
+ BlockJobType_lookup[driver->job_type]);
+ bdrv_op_block_all(bs, job->blocker);
+ bdrv_op_unblock(bs, BLOCK_OP_TYPE_DATAPLANE, job->blocker);
+
+ job->driver = driver;
+ job->bs = bs;
+ job->cb = cb;
+ job->opaque = opaque;
+ job->busy = true;
+ bs->job = job;
+
+ /* Only set speed when necessary to avoid NotSupported error */
+ if (speed != 0) {
+ Error *local_err = NULL;
+
+ block_job_set_speed(job, speed, &local_err);
+ if (local_err) {
+ block_job_release(bs);
+ error_propagate(errp, local_err);
+ return NULL;
+ }
+ }
+ return job;
+}
+
+void block_job_release(BlockDriverState *bs)
+{
+ BlockJob *job = bs->job;
+
+ bs->job = NULL;
+ bdrv_op_unblock_all(bs, job->blocker);
+ error_free(job->blocker);
+ g_free(job);
+}
+
+void block_job_completed(BlockJob *job, int ret)
+{
+ BlockDriverState *bs = job->bs;
+
+ assert(bs->job == job);
+ job->cb(job->opaque, ret);
+ block_job_release(bs);
+}
+
+void block_job_set_speed(BlockJob *job, int64_t speed, Error **errp)
+{
+ Error *local_err = NULL;
+
+ if (!job->driver->set_speed) {
+ error_setg(errp, QERR_UNSUPPORTED);
+ return;
+ }
+ job->driver->set_speed(job, speed, &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ return;
+ }
+
+ job->speed = speed;
+}
+
+void block_job_complete(BlockJob *job, Error **errp)
+{
+ if (job->pause_count || job->cancelled || !job->driver->complete) {
+ error_setg(errp, QERR_BLOCK_JOB_NOT_READY,
+ bdrv_get_device_name(job->bs));
+ return;
+ }
+
+ job->driver->complete(job, errp);
+}
+
+void block_job_pause(BlockJob *job)
+{
+ job->pause_count++;
+}
+
+bool block_job_is_paused(BlockJob *job)
+{
+ return job->pause_count > 0;
+}
+
+void block_job_resume(BlockJob *job)
+{
+ assert(job->pause_count > 0);
+ job->pause_count--;
+ if (job->pause_count) {
+ return;
+ }
+ block_job_enter(job);
+}
+
+void block_job_enter(BlockJob *job)
+{
+ block_job_iostatus_reset(job);
+ if (job->co && !job->busy) {
+ qemu_coroutine_enter(job->co, NULL);
+ }
+}
+
+void block_job_cancel(BlockJob *job)
+{
+ job->cancelled = true;
+ block_job_enter(job);
+}
+
+bool block_job_is_cancelled(BlockJob *job)
+{
+ return job->cancelled;
+}
+
+void block_job_iostatus_reset(BlockJob *job)
+{
+ job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
+ if (job->driver->iostatus_reset) {
+ job->driver->iostatus_reset(job);
+ }
+}
+
+struct BlockFinishData {
+ BlockJob *job;
+ BlockCompletionFunc *cb;
+ void *opaque;
+ bool cancelled;
+ int ret;
+};
+
+static void block_job_finish_cb(void *opaque, int ret)
+{
+ struct BlockFinishData *data = opaque;
+
+ data->cancelled = block_job_is_cancelled(data->job);
+ data->ret = ret;
+ data->cb(data->opaque, ret);
+}
+
+static int block_job_finish_sync(BlockJob *job,
+ void (*finish)(BlockJob *, Error **errp),
+ Error **errp)
+{
+ struct BlockFinishData data;
+ BlockDriverState *bs = job->bs;
+ Error *local_err = NULL;
+
+ assert(bs->job == job);
+
+ /* Set up our own callback to store the result and chain to
+ * the original callback.
+ */
+ data.job = job;
+ data.cb = job->cb;
+ data.opaque = job->opaque;
+ data.ret = -EINPROGRESS;
+ job->cb = block_job_finish_cb;
+ job->opaque = &data;
+ finish(job, &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ return -EBUSY;
+ }
+ while (data.ret == -EINPROGRESS) {
+ aio_poll(bdrv_get_aio_context(bs), true);
+ }
+ return (data.cancelled && data.ret == 0) ? -ECANCELED : data.ret;
+}
+
+/* A wrapper around block_job_cancel() taking an Error ** parameter so it may be
+ * used with block_job_finish_sync() without the need for (rather nasty)
+ * function pointer casts there. */
+static void block_job_cancel_err(BlockJob *job, Error **errp)
+{
+ block_job_cancel(job);
+}
+
+int block_job_cancel_sync(BlockJob *job)
+{
+ return block_job_finish_sync(job, &block_job_cancel_err, NULL);
+}
+
+int block_job_complete_sync(BlockJob *job, Error **errp)
+{
+ return block_job_finish_sync(job, &block_job_complete, errp);
+}
+
+void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns)
+{
+ assert(job->busy);
+
+ /* Check cancellation *before* setting busy = false, too! */
+ if (block_job_is_cancelled(job)) {
+ return;
+ }
+
+ job->busy = false;
+ if (block_job_is_paused(job)) {
+ qemu_coroutine_yield();
+ } else {
+ co_aio_sleep_ns(bdrv_get_aio_context(job->bs), type, ns);
+ }
+ job->busy = true;
+}
+
+void block_job_yield(BlockJob *job)
+{
+ assert(job->busy);
+
+ /* Check cancellation *before* setting busy = false, too! */
+ if (block_job_is_cancelled(job)) {
+ return;
+ }
+
+ job->busy = false;
+ qemu_coroutine_yield();
+ job->busy = true;
+}
+
+BlockJobInfo *block_job_query(BlockJob *job)
+{
+ BlockJobInfo *info = g_new0(BlockJobInfo, 1);
+ info->type = g_strdup(BlockJobType_lookup[job->driver->job_type]);
+ info->device = g_strdup(bdrv_get_device_name(job->bs));
+ info->len = job->len;
+ info->busy = job->busy;
+ info->paused = job->pause_count > 0;
+ info->offset = job->offset;
+ info->speed = job->speed;
+ info->io_status = job->iostatus;
+ info->ready = job->ready;
+ return info;
+}
+
+static void block_job_iostatus_set_err(BlockJob *job, int error)
+{
+ if (job->iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
+ job->iostatus = error == ENOSPC ? BLOCK_DEVICE_IO_STATUS_NOSPACE :
+ BLOCK_DEVICE_IO_STATUS_FAILED;
+ }
+}
+
+void block_job_event_cancelled(BlockJob *job)
+{
+ qapi_event_send_block_job_cancelled(job->driver->job_type,
+ bdrv_get_device_name(job->bs),
+ job->len,
+ job->offset,
+ job->speed,
+ &error_abort);
+}
+
+void block_job_event_completed(BlockJob *job, const char *msg)
+{
+ qapi_event_send_block_job_completed(job->driver->job_type,
+ bdrv_get_device_name(job->bs),
+ job->len,
+ job->offset,
+ job->speed,
+ !!msg,
+ msg,
+ &error_abort);
+}
+
+void block_job_event_ready(BlockJob *job)
+{
+ job->ready = true;
+
+ qapi_event_send_block_job_ready(job->driver->job_type,
+ bdrv_get_device_name(job->bs),
+ job->len,
+ job->offset,
+ job->speed, &error_abort);
+}
+
+BlockErrorAction block_job_error_action(BlockJob *job, BlockDriverState *bs,
+ BlockdevOnError on_err,
+ int is_read, int error)
+{
+ BlockErrorAction action;
+
+ switch (on_err) {
+ case BLOCKDEV_ON_ERROR_ENOSPC:
+ action = (error == ENOSPC) ?
+ BLOCK_ERROR_ACTION_STOP : BLOCK_ERROR_ACTION_REPORT;
+ break;
+ case BLOCKDEV_ON_ERROR_STOP:
+ action = BLOCK_ERROR_ACTION_STOP;
+ break;
+ case BLOCKDEV_ON_ERROR_REPORT:
+ action = BLOCK_ERROR_ACTION_REPORT;
+ break;
+ case BLOCKDEV_ON_ERROR_IGNORE:
+ action = BLOCK_ERROR_ACTION_IGNORE;
+ break;
+ default:
+ abort();
+ }
+ qapi_event_send_block_job_error(bdrv_get_device_name(job->bs),
+ is_read ? IO_OPERATION_TYPE_READ :
+ IO_OPERATION_TYPE_WRITE,
+ action, &error_abort);
+ if (action == BLOCK_ERROR_ACTION_STOP) {
+ /* make the pause user visible, which will be resumed from QMP. */
+ job->user_paused = true;
+ block_job_pause(job);
+ block_job_iostatus_set_err(job, error);
+ if (bs != job->bs) {
+ bdrv_iostatus_set_err(bs, error);
+ }
+ }
+ return action;
+}
+
+typedef struct {
+ BlockJob *job;
+ QEMUBH *bh;
+ AioContext *aio_context;
+ BlockJobDeferToMainLoopFn *fn;
+ void *opaque;
+} BlockJobDeferToMainLoopData;
+
+static void block_job_defer_to_main_loop_bh(void *opaque)
+{
+ BlockJobDeferToMainLoopData *data = opaque;
+ AioContext *aio_context;
+
+ qemu_bh_delete(data->bh);
+
+ /* Prevent race with block_job_defer_to_main_loop() */
+ aio_context_acquire(data->aio_context);
+
+ /* Fetch BDS AioContext again, in case it has changed */
+ aio_context = bdrv_get_aio_context(data->job->bs);
+ aio_context_acquire(aio_context);
+
+ data->fn(data->job, data->opaque);
+
+ aio_context_release(aio_context);
+
+ aio_context_release(data->aio_context);
+
+ g_free(data);
+}
+
+void block_job_defer_to_main_loop(BlockJob *job,
+ BlockJobDeferToMainLoopFn *fn,
+ void *opaque)
+{
+ BlockJobDeferToMainLoopData *data = g_malloc(sizeof(*data));
+ data->job = job;
+ data->bh = qemu_bh_new(block_job_defer_to_main_loop_bh, data);
+ data->aio_context = bdrv_get_aio_context(job->bs);
+ data->fn = fn;
+ data->opaque = opaque;
+
+ qemu_bh_schedule(data->bh);
+}
Code Review / kvmfornfv.git / blobdiff