From c818a1cb603cad07aa5c49ce808aa09435667c7c Mon Sep 17 00:00:00 2001 From: "Dr. David Alan Gilbert" Date: Mon, 27 Jan 2020 19:01:04 +0100 Subject: [PATCH 033/116] virtiofsd: Keep track of replies MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit RH-Author: Dr. David Alan Gilbert Message-id: <20200127190227.40942-30-dgilbert@redhat.com> Patchwork-id: 93481 O-Subject: [RHEL-AV-8.2 qemu-kvm PATCH 029/112] virtiofsd: Keep track of replies Bugzilla: 1694164 RH-Acked-by: Philippe Mathieu-Daudé RH-Acked-by: Stefan Hajnoczi RH-Acked-by: Sergio Lopez Pascual From: "Dr. David Alan Gilbert" Keep track of whether we sent a reply to a request; this is a bit paranoid but it means: a) We should always recycle an element even if there was an error in the request b) Never try and send two replies on one queue element Signed-off-by: Dr. David Alan Gilbert Reviewed-by: Daniel P. Berrangé Signed-off-by: Dr. David Alan Gilbert (cherry picked from commit 2f65e69a7f22da8d20c747f34f339ebb40a0634f) Signed-off-by: Miroslav Rezanina --- tools/virtiofsd/fuse_virtio.c | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-) diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c index 05d0e29..f1adeb6 100644 --- a/tools/virtiofsd/fuse_virtio.c +++ b/tools/virtiofsd/fuse_virtio.c @@ -44,6 +44,7 @@ struct fv_QueueInfo { /* The element for the command currently being processed */ VuVirtqElement *qe; + bool reply_sent; }; /* @@ -178,6 +179,7 @@ int virtio_send_msg(struct fuse_session *se, struct fuse_chan *ch, { VuVirtqElement *elem; VuVirtq *q; + int ret = 0; assert(count >= 1); assert(iov[0].iov_len >= sizeof(struct fuse_out_header)); @@ -191,6 +193,7 @@ int virtio_send_msg(struct fuse_session *se, struct fuse_chan *ch, assert(out->unique); /* For virtio we always have ch */ assert(ch); + assert(!ch->qi->reply_sent); elem = ch->qi->qe; q = &ch->qi->virtio_dev->dev.vq[ch->qi->qidx]; @@ -208,19 +211,23 @@ int virtio_send_msg(struct fuse_session *se, struct fuse_chan *ch, if (in_len < sizeof(struct fuse_out_header)) { fuse_log(FUSE_LOG_ERR, "%s: elem %d too short for out_header\n", __func__, elem->index); - return -E2BIG; + ret = -E2BIG; + goto err; } if (in_len < tosend_len) { fuse_log(FUSE_LOG_ERR, "%s: elem %d too small for data len %zd\n", __func__, elem->index, tosend_len); - return -E2BIG; + ret = -E2BIG; + goto err; } copy_iov(iov, count, in_sg, in_num, tosend_len); vu_queue_push(&se->virtio_dev->dev, q, elem, tosend_len); vu_queue_notify(&se->virtio_dev->dev, q); + ch->qi->reply_sent = true; - return 0; +err: + return ret; } /* Thread function for individual queues, created when a queue is 'started' */ @@ -296,6 +303,9 @@ static void *fv_queue_thread(void *opaque) break; } + qi->qe = elem; + qi->reply_sent = false; + if (!fbuf.mem) { fbuf.mem = malloc(se->bufsize); assert(fbuf.mem); @@ -331,6 +341,13 @@ static void *fv_queue_thread(void *opaque) /* TODO: Add checks for fuse_session_exited */ fuse_session_process_buf_int(se, &fbuf, &ch); + if (!qi->reply_sent) { + fuse_log(FUSE_LOG_DEBUG, "%s: elem %d no reply sent\n", + __func__, elem->index); + /* I think we've still got to recycle the element */ + vu_queue_push(dev, q, elem, 0); + vu_queue_notify(dev, q); + } qi->qe = NULL; free(elem); elem = NULL; -- 1.8.3.1