Commit f42b2207 authored by Paolo Bonzini's avatar Paolo Bonzini

aio: add Win32 implementation

The Win32 implementation will only accept EventNotifiers, thus a few
drivers are disabled under Windows.  EventNotifiers are a good match
for the GSource implementation, too, because the Win32 port of glib
allows to place their HANDLEs in a GPollFD.
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent cd9ba1eb
......@@ -42,12 +42,12 @@ coroutine-obj-$(CONFIG_WIN32) += coroutine-win32.o
# block-obj-y is code used by both qemu system emulation and qemu-img
block-obj-y = iov.o cache-utils.o qemu-option.o module.o async.o
block-obj-y += nbd.o block.o blockjob.o aio.o aes.o qemu-config.o
block-obj-y += nbd.o block.o blockjob.o aes.o qemu-config.o
block-obj-y += qemu-progress.o qemu-sockets.o uri.o notify.o
block-obj-y += $(coroutine-obj-y) $(qobject-obj-y) $(version-obj-y)
block-obj-$(CONFIG_POSIX) += posix-aio-compat.o
block-obj-$(CONFIG_POSIX) += event_notifier-posix.o
block-obj-$(CONFIG_WIN32) += event_notifier-win32.o
block-obj-$(CONFIG_POSIX) += event_notifier-posix.o aio-posix.o
block-obj-$(CONFIG_WIN32) += event_notifier-win32.o aio-win32.o
block-obj-$(CONFIG_LINUX_AIO) += linux-aio.o
block-obj-y += block/
block-obj-y += $(qapi-obj-y) qapi-types.o qapi-visit.o
......
/*
* QEMU aio implementation
*
* Copyright IBM Corp., 2008
* Copyright Red Hat Inc., 2012
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
* Paolo Bonzini <pbonzini@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
* Contributions after 2012-01-13 are licensed under the terms of the
* GNU GPL, version 2 or (at your option) any later version.
*/
#include "qemu-common.h"
#include "block.h"
#include "qemu-queue.h"
#include "qemu_socket.h"
struct AioHandler {
EventNotifier *e;
EventNotifierHandler *io_notify;
AioFlushEventNotifierHandler *io_flush;
GPollFD pfd;
int deleted;
QLIST_ENTRY(AioHandler) node;
};
void aio_set_event_notifier(AioContext *ctx,
EventNotifier *e,
EventNotifierHandler *io_notify,
AioFlushEventNotifierHandler *io_flush)
{
AioHandler *node;
QLIST_FOREACH(node, &ctx->aio_handlers, node) {
if (node->e == e && !node->deleted) {
break;
}
}
/* Are we deleting the fd handler? */
if (!io_notify) {
if (node) {
/* If the lock is held, just mark the node as deleted */
if (ctx->walking_handlers) {
node->deleted = 1;
node->pfd.revents = 0;
} else {
/* Otherwise, delete it for real. We can't just mark it as
* deleted because deleted nodes are only cleaned up after
* releasing the walking_handlers lock.
*/
QLIST_REMOVE(node, node);
g_free(node);
}
}
} else {
if (node == NULL) {
/* Alloc and insert if it's not already there */
node = g_malloc0(sizeof(AioHandler));
node->e = e;
node->pfd.fd = (uintptr_t)event_notifier_get_handle(e);
node->pfd.events = G_IO_IN;
QLIST_INSERT_HEAD(&ctx->aio_handlers, node, node);
}
/* Update handler with latest information */
node->io_notify = io_notify;
node->io_flush = io_flush;
}
}
bool aio_pending(AioContext *ctx)
{
AioHandler *node;
QLIST_FOREACH(node, &ctx->aio_handlers, node) {
if (node->pfd.revents && node->io_notify) {
return true;
}
}
return false;
}
bool aio_poll(AioContext *ctx, bool blocking)
{
AioHandler *node;
HANDLE events[MAXIMUM_WAIT_OBJECTS + 1];
bool busy, progress;
int count;
progress = false;
/*
* If there are callbacks left that have been queued, we need to call then.
* Do not call select in this case, because it is possible that the caller
* does not need a complete flush (as is the case for qemu_aio_wait loops).
*/
if (aio_bh_poll(ctx)) {
blocking = false;
progress = true;
}
/*
* Then dispatch any pending callbacks from the GSource.
*
* We have to walk very carefully in case qemu_aio_set_fd_handler is
* called while we're walking.
*/
node = QLIST_FIRST(&ctx->aio_handlers);
while (node) {
AioHandler *tmp;
ctx->walking_handlers++;
if (node->pfd.revents && node->io_notify) {
node->pfd.revents = 0;
node->io_notify(node->e);
progress = true;
}
tmp = node;
node = QLIST_NEXT(node, node);
ctx->walking_handlers--;
if (!ctx->walking_handlers && tmp->deleted) {
QLIST_REMOVE(tmp, node);
g_free(tmp);
}
}
if (progress && !blocking) {
return true;
}
ctx->walking_handlers++;
/* fill fd sets */
busy = false;
count = 0;
QLIST_FOREACH(node, &ctx->aio_handlers, node) {
/* If there aren't pending AIO operations, don't invoke callbacks.
* Otherwise, if there are no AIO requests, qemu_aio_wait() would
* wait indefinitely.
*/
if (!node->deleted && node->io_flush) {
if (node->io_flush(node->e) == 0) {
continue;
}
busy = true;
}
if (!node->deleted && node->io_notify) {
events[count++] = event_notifier_get_handle(node->e);
}
}
ctx->walking_handlers--;
/* No AIO operations? Get us out of here */
if (!busy) {
return progress;
}
/* wait until next event */
for (;;) {
int timeout = blocking ? INFINITE : 0;
int ret = WaitForMultipleObjects(count, events, FALSE, timeout);
/* if we have any signaled events, dispatch event */
if ((DWORD) (ret - WAIT_OBJECT_0) >= count) {
break;
}
blocking = false;
/* we have to walk very carefully in case
* qemu_aio_set_fd_handler is called while we're walking */
node = QLIST_FIRST(&ctx->aio_handlers);
while (node) {
AioHandler *tmp;
ctx->walking_handlers++;
if (!node->deleted &&
event_notifier_get_handle(node->e) == events[ret - WAIT_OBJECT_0] &&
node->io_notify) {
node->io_notify(node->e);
progress = true;
}
tmp = node;
node = QLIST_NEXT(node, node);
ctx->walking_handlers--;
if (!ctx->walking_handlers && tmp->deleted) {
QLIST_REMOVE(tmp, node);
g_free(tmp);
}
}
}
return progress;
}
......@@ -2,13 +2,17 @@ block-obj-y += raw.o cow.o qcow.o vdi.o vmdk.o cloop.o dmg.o bochs.o vpc.o vvfat
block-obj-y += qcow2.o qcow2-refcount.o qcow2-cluster.o qcow2-snapshot.o qcow2-cache.o
block-obj-y += qed.o qed-gencb.o qed-l2-cache.o qed-table.o qed-cluster.o
block-obj-y += qed-check.o
block-obj-y += parallels.o nbd.o blkdebug.o sheepdog.o blkverify.o
block-obj-y += parallels.o blkdebug.o blkverify.o
block-obj-$(CONFIG_WIN32) += raw-win32.o
block-obj-$(CONFIG_POSIX) += raw-posix.o
ifeq ($(CONFIG_POSIX),y)
block-obj-y += nbd.o sheepdog.o
block-obj-$(CONFIG_LIBISCSI) += iscsi.o
block-obj-$(CONFIG_CURL) += curl.o
block-obj-$(CONFIG_RBD) += rbd.o
block-obj-$(CONFIG_GLUSTERFS) += gluster.o
endif
common-obj-y += stream.o
common-obj-y += commit.o
......@@ -537,6 +537,7 @@ bool qemu_aio_wait(void)
return aio_poll(qemu_aio_context, true);
}
#ifdef CONFIG_POSIX
void qemu_aio_set_fd_handler(int fd,
IOHandler *io_read,
IOHandler *io_write,
......@@ -549,7 +550,6 @@ void qemu_aio_set_fd_handler(int fd,
qemu_set_fd_handler2(fd, NULL, io_read, io_write, opaque);
}
#ifdef CONFIG_POSIX
void qemu_aio_set_event_notifier(EventNotifier *notifier,
EventNotifierHandler *io_read,
AioFlushEventNotifierHandler *io_flush)
......
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