ssh: support I/O from any AioContext
The coroutine may run in a different AioContext, causing the
fd handler to busy wait. Fix this by resetting the handler
in restart_coroutine, before the coroutine is restarted.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20170629132749.997-12-pbonzini@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
diff --git a/block/ssh.c b/block/ssh.c
index 07a57eb..e8f0404 100644
--- a/block/ssh.c
+++ b/block/ssh.c
@@ -888,13 +888,22 @@
return has_zero_init;
}
+typedef struct BDRVSSHRestart {
+ BlockDriverState *bs;
+ Coroutine *co;
+} BDRVSSHRestart;
+
static void restart_coroutine(void *opaque)
{
- Coroutine *co = opaque;
+ BDRVSSHRestart *restart = opaque;
+ BlockDriverState *bs = restart->bs;
+ BDRVSSHState *s = bs->opaque;
+ AioContext *ctx = bdrv_get_aio_context(bs);
- DPRINTF("co=%p", co);
+ DPRINTF("co=%p", restart->co);
+ aio_set_fd_handler(ctx, s->sock, false, NULL, NULL, NULL, NULL);
- aio_co_wake(co);
+ aio_co_wake(restart->co);
}
/* A non-blocking call returned EAGAIN, so yield, ensuring the
@@ -905,7 +914,10 @@
{
int r;
IOHandler *rd_handler = NULL, *wr_handler = NULL;
- Coroutine *co = qemu_coroutine_self();
+ BDRVSSHRestart restart = {
+ .bs = bs,
+ .co = qemu_coroutine_self()
+ };
r = libssh2_session_block_directions(s->session);
@@ -920,11 +932,9 @@
rd_handler, wr_handler);
aio_set_fd_handler(bdrv_get_aio_context(bs), s->sock,
- false, rd_handler, wr_handler, NULL, co);
+ false, rd_handler, wr_handler, NULL, &restart);
qemu_coroutine_yield();
DPRINTF("s->sock=%d - back", s->sock);
- aio_set_fd_handler(bdrv_get_aio_context(bs), s->sock, false,
- NULL, NULL, NULL, NULL);
}
/* SFTP has a function `libssh2_sftp_seek64' which seeks to a position