Simply exposed a block.c API, and added a AIO check function.
Signed-off-by: Wenchao Xia <xiaw...@linux.vnet.ibm.com>
---
aio.c | 95 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
block.c | 2 +-
block.h | 1 +
qemu-aio.h | 1 +
4 files changed, 98 insertions(+), 1 deletions(-)
diff --git a/aio.c b/aio.c
index 0a9eb10..dbe0f6f 100644
--- a/aio.c
+++ b/aio.c
@@ -192,3 +192,98 @@ bool qemu_aio_wait(void)
return true;
}
+
+
+bool qemu_aio_check(void)
+{
+ AioHandler *node;
+ fd_set rdfds, wrfds;
+ int max_fd = -1;
+ int ret;
+ bool busy;
+ struct timeval tv;
+
+ walking_handlers = 1;
+
+ FD_ZERO(&rdfds);
+ FD_ZERO(&wrfds);
+
+ /* fill fd sets */
+ busy = false;
+ QLIST_FOREACH(node, &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->io_flush) {
+ if (node->io_flush(node->opaque) == 0) {
+ continue;
+ }
+ busy = true;
+ }
+ if (!node->deleted && node->io_read) {
+ FD_SET(node->fd, &rdfds);
+ max_fd = MAX(max_fd, node->fd + 1);
+ }
+ if (!node->deleted && node->io_write) {
+ FD_SET(node->fd, &wrfds);
+ max_fd = MAX(max_fd, node->fd + 1);
+ }
+ }
+
+ walking_handlers = 0;
+
+ /* No AIO operations? Get us out of here */
+ if (!busy) {
+ return false;
+ }
+
+ tv.tv_sec = 0;
+ tv.tv_usec = 0;
+ /* wait until next event */
+ ret = select(max_fd, &rdfds, &wrfds, NULL, &tv);
+
+ /* if we have any readable fds, dispatch event */
+ if (ret > 0) {
+ walking_handlers = 1;
+
+ /* we have to walk very carefully in case
+ * qemu_aio_set_fd_handler is called while we're walking */
+ node = QLIST_FIRST(&aio_handlers);
+ while (node) {
+ AioHandler *tmp;
+
+ if (!node->deleted &&
+ FD_ISSET(node->fd, &rdfds) &&
+ node->io_read) {
+ node->io_read(node->opaque);
+ }
+ if (!node->deleted &&
+ FD_ISSET(node->fd, &wrfds) &&
+ node->io_write) {
+ node->io_write(node->opaque);
+ }
+
+ tmp = node;
+ node = QLIST_NEXT(node, node);
+
+ if (tmp->deleted) {
+ QLIST_REMOVE(tmp, node);
+ g_free(tmp);
+ }
+ }
+
+ walking_handlers = 0;
+ }
+
+ /*
+ * 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 (qemu_bh_poll()) {
+ return true;
+ }
+
+ return true;
+}
diff --git a/block.c b/block.c
index b38940b..d30f363 100644
--- a/block.c
+++ b/block.c
@@ -196,7 +196,7 @@ static void bdrv_io_limits_intercept(BlockDriverState *bs,
}
/* check if the path starts with "<protocol>:" */
-static int path_has_protocol(const char *path)
+int path_has_protocol(const char *path)
{
const char *p;
diff --git a/block.h b/block.h
index c89590d..3aca2fd 100644
--- a/block.h
+++ b/block.h
@@ -403,4 +403,5 @@ typedef enum {
#define BLKDBG_EVENT(bs, evt) bdrv_debug_event(bs, evt)
void bdrv_debug_event(BlockDriverState *bs, BlkDebugEvent event);
+int path_has_protocol(const char *path);
#endif
diff --git a/qemu-aio.h b/qemu-aio.h
index bfdd35f..b34eb16 100644
--- a/qemu-aio.h
+++ b/qemu-aio.h
@@ -66,4 +66,5 @@ int qemu_aio_set_fd_handler(int fd,
AioFlushHandler *io_flush,
void *opaque);
+bool qemu_aio_check(void);
#endif
--
1.7.1
