mirror of
https://github.com/qemu/qemu.git
synced 2024-11-24 19:33:39 +08:00
3ab72385b2
The generated qapi_event_send_FOO() take an Error ** argument. They can't actually fail, because all they do with the argument is passing it to functions that can't fail: the QObject output visitor, and the @qmp_emit callback, which is either monitor_qapi_event_queue() or event_test_emit(). Drop the argument, and pass &error_abort to the QObject output visitor and @qmp_emit instead. Suggested-by: Eric Blake <eblake@redhat.com> Suggested-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20180815133747.25032-4-peterx@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> [Commit message rewritten, update to qapi-code-gen.txt corrected] Signed-off-by: Markus Armbruster <armbru@redhat.com>
125 lines
3.5 KiB
C
125 lines
3.5 KiB
C
/*
|
|
* QEMU System Emulator block write threshold notification
|
|
*
|
|
* Copyright Red Hat, Inc. 2014
|
|
*
|
|
* Authors:
|
|
* Francesco Romani <fromani@redhat.com>
|
|
*
|
|
* This work is licensed under the terms of the GNU LGPL, version 2 or later.
|
|
* See the COPYING.LIB file in the top-level directory.
|
|
*/
|
|
|
|
#include "qemu/osdep.h"
|
|
#include "block/block_int.h"
|
|
#include "qemu/coroutine.h"
|
|
#include "block/write-threshold.h"
|
|
#include "qemu/notify.h"
|
|
#include "qapi/error.h"
|
|
#include "qapi/qapi-commands-block-core.h"
|
|
#include "qapi/qapi-events-block-core.h"
|
|
|
|
uint64_t bdrv_write_threshold_get(const BlockDriverState *bs)
|
|
{
|
|
return bs->write_threshold_offset;
|
|
}
|
|
|
|
bool bdrv_write_threshold_is_set(const BlockDriverState *bs)
|
|
{
|
|
return bs->write_threshold_offset > 0;
|
|
}
|
|
|
|
static void write_threshold_disable(BlockDriverState *bs)
|
|
{
|
|
if (bdrv_write_threshold_is_set(bs)) {
|
|
notifier_with_return_remove(&bs->write_threshold_notifier);
|
|
bs->write_threshold_offset = 0;
|
|
}
|
|
}
|
|
|
|
uint64_t bdrv_write_threshold_exceeded(const BlockDriverState *bs,
|
|
const BdrvTrackedRequest *req)
|
|
{
|
|
if (bdrv_write_threshold_is_set(bs)) {
|
|
if (req->offset > bs->write_threshold_offset) {
|
|
return (req->offset - bs->write_threshold_offset) + req->bytes;
|
|
}
|
|
if ((req->offset + req->bytes) > bs->write_threshold_offset) {
|
|
return (req->offset + req->bytes) - bs->write_threshold_offset;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int coroutine_fn before_write_notify(NotifierWithReturn *notifier,
|
|
void *opaque)
|
|
{
|
|
BdrvTrackedRequest *req = opaque;
|
|
BlockDriverState *bs = req->bs;
|
|
uint64_t amount = 0;
|
|
|
|
amount = bdrv_write_threshold_exceeded(bs, req);
|
|
if (amount > 0) {
|
|
qapi_event_send_block_write_threshold(
|
|
bs->node_name,
|
|
amount,
|
|
bs->write_threshold_offset);
|
|
|
|
/* autodisable to avoid flooding the monitor */
|
|
write_threshold_disable(bs);
|
|
}
|
|
|
|
return 0; /* should always let other notifiers run */
|
|
}
|
|
|
|
static void write_threshold_register_notifier(BlockDriverState *bs)
|
|
{
|
|
bs->write_threshold_notifier.notify = before_write_notify;
|
|
bdrv_add_before_write_notifier(bs, &bs->write_threshold_notifier);
|
|
}
|
|
|
|
static void write_threshold_update(BlockDriverState *bs,
|
|
int64_t threshold_bytes)
|
|
{
|
|
bs->write_threshold_offset = threshold_bytes;
|
|
}
|
|
|
|
void bdrv_write_threshold_set(BlockDriverState *bs, uint64_t threshold_bytes)
|
|
{
|
|
if (bdrv_write_threshold_is_set(bs)) {
|
|
if (threshold_bytes > 0) {
|
|
write_threshold_update(bs, threshold_bytes);
|
|
} else {
|
|
write_threshold_disable(bs);
|
|
}
|
|
} else {
|
|
if (threshold_bytes > 0) {
|
|
/* avoid multiple registration */
|
|
write_threshold_register_notifier(bs);
|
|
write_threshold_update(bs, threshold_bytes);
|
|
}
|
|
/* discard bogus disable request */
|
|
}
|
|
}
|
|
|
|
void qmp_block_set_write_threshold(const char *node_name,
|
|
uint64_t threshold_bytes,
|
|
Error **errp)
|
|
{
|
|
BlockDriverState *bs;
|
|
AioContext *aio_context;
|
|
|
|
bs = bdrv_find_node(node_name);
|
|
if (!bs) {
|
|
error_setg(errp, "Device '%s' not found", node_name);
|
|
return;
|
|
}
|
|
|
|
aio_context = bdrv_get_aio_context(bs);
|
|
aio_context_acquire(aio_context);
|
|
|
|
bdrv_write_threshold_set(bs, threshold_bytes);
|
|
|
|
aio_context_release(aio_context);
|
|
}
|