#include "block/raw-aio.h"
#include "qemu/event_notifier.h"
#include "qemu/coroutine.h"
+#include "qapi/error.h"
#include <libaio.h>
io_context_t ctx;
EventNotifier e;
- /* io queue for submit at batch */
+ /* io queue for submit at batch. Protected by AioContext lock. */
LaioQueue io_q;
- /* I/O completion processing */
+ /* I/O completion processing. Only runs in I/O thread. */
QEMUBH *completion_bh;
int event_idx;
int event_max;
laiocb->ret = ret;
if (laiocb->co) {
- /* Jump and continue completion for foreign requests, don't do
- * anything for current request, it will be completed shortly. */
- if (laiocb->co != qemu_coroutine_self()) {
- qemu_coroutine_enter(laiocb->co);
+ /* If the coroutine is already entered it must be in ioq_submit() and
+ * will notice laio->ret has been filled in when it eventually runs
+ * later. Coroutines cannot be entered recursively so avoid doing
+ * that!
+ */
+ if (!qemu_coroutine_entered(laiocb->co)) {
+ aio_co_wake(laiocb->co);
}
} else {
laiocb->common.cb(laiocb->common.opaque, ret);
static void qemu_laio_process_completions_and_submit(LinuxAioState *s)
{
+ aio_context_acquire(s->aio_context);
qemu_laio_process_completions(s);
+
if (!s->io_q.plugged && !QSIMPLEQ_EMPTY(&s->io_q.pending)) {
ioq_submit(s);
}
+ aio_context_release(s->aio_context);
}
static void qemu_laio_completion_bh(void *opaque)
}
}
+static bool qemu_laio_poll_cb(void *opaque)
+{
+ EventNotifier *e = opaque;
+ LinuxAioState *s = container_of(e, LinuxAioState, e);
+ struct io_event *events;
+
+ if (!io_getevents_peek(s->ctx, &events)) {
+ return false;
+ }
+
+ qemu_laio_process_completions_and_submit(s);
+ return true;
+}
+
static void laio_cancel(BlockAIOCB *blockacb)
{
struct qemu_laiocb *laiocb = (struct qemu_laiocb *)blockacb;
switch (type) {
case QEMU_AIO_WRITE:
io_prep_pwritev(iocbs, fd, qiov->iov, qiov->niov, offset);
- break;
+ break;
case QEMU_AIO_READ:
io_prep_preadv(iocbs, fd, qiov->iov, qiov->niov, offset);
- break;
+ break;
/* Currently Linux kernel does not support other operations */
default:
fprintf(stderr, "%s: invalid AIO request type 0x%x.\n",
void laio_detach_aio_context(LinuxAioState *s, AioContext *old_context)
{
- aio_set_event_notifier(old_context, &s->e, false, NULL);
+ aio_set_event_notifier(old_context, &s->e, false, NULL, NULL);
qemu_bh_delete(s->completion_bh);
+ s->aio_context = NULL;
}
void laio_attach_aio_context(LinuxAioState *s, AioContext *new_context)
s->aio_context = new_context;
s->completion_bh = aio_bh_new(new_context, qemu_laio_completion_bh, s);
aio_set_event_notifier(new_context, &s->e, false,
- qemu_laio_completion_cb);
+ qemu_laio_completion_cb,
+ qemu_laio_poll_cb);
}
-LinuxAioState *laio_init(void)
+LinuxAioState *laio_init(Error **errp)
{
+ int rc;
LinuxAioState *s;
s = g_malloc0(sizeof(*s));
- if (event_notifier_init(&s->e, false) < 0) {
+ rc = event_notifier_init(&s->e, false);
+ if (rc < 0) {
+ error_setg_errno(errp, -rc, "failed to to initialize event notifier");
goto out_free_state;
}
- if (io_setup(MAX_EVENTS, &s->ctx) != 0) {
+ rc = io_setup(MAX_EVENTS, &s->ctx);
+ if (rc < 0) {
+ error_setg_errno(errp, -rc, "failed to create linux AIO context");
goto out_close_efd;
}