vhost: do not assert() on vhost_ops failure

Calling a vhost operation may fail, for example with disconnected
vhost-user backend, but qemu shouldn't abort in this case.

Log an error instead, except on error and cleanup code paths where it
can be mostly ignored.

Let's use a VHOST_OPS_DEBUG macro to easily disable those messages once
disconnected backend stabilizes.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Marc-André Lureau 2016-07-27 01:15:05 +04:00 committed by Michael S. Tsirkin
parent a06db3ec72
commit 162bba7fa8

View File

@ -27,6 +27,18 @@
#include "hw/virtio/virtio-access.h"
#include "migration/migration.h"
/* enabled until disconnected backend stabilizes */
#define _VHOST_DEBUG 1
#ifdef _VHOST_DEBUG
#define VHOST_OPS_DEBUG(fmt, ...) \
do { error_report(fmt ": %s (%d)", ## __VA_ARGS__, \
strerror(errno), errno); } while (0)
#else
#define VHOST_OPS_DEBUG(fmt, ...) \
do { } while (0)
#endif
static struct vhost_log *vhost_log;
static struct vhost_log *vhost_log_shm;
@ -400,7 +412,10 @@ static inline void vhost_dev_log_resize(struct vhost_dev *dev, uint64_t size)
/* inform backend of log switching, this must be done before
releasing the current log, to ensure no logging is lost */
r = dev->vhost_ops->vhost_set_log_base(dev, log_base, log);
assert(r >= 0);
if (r < 0) {
VHOST_OPS_DEBUG("vhost_set_log_base failed");
}
vhost_log_put(dev, true);
dev->log = log;
dev->log_size = size;
@ -567,7 +582,9 @@ static void vhost_commit(MemoryListener *listener)
if (!dev->log_enabled) {
r = dev->vhost_ops->vhost_set_mem_table(dev, dev->mem);
assert(r >= 0);
if (r < 0) {
VHOST_OPS_DEBUG("vhost_set_mem_table failed");
}
dev->memory_changed = false;
return;
}
@ -580,7 +597,9 @@ static void vhost_commit(MemoryListener *listener)
vhost_dev_log_resize(dev, log_size + VHOST_LOG_BUFFER);
}
r = dev->vhost_ops->vhost_set_mem_table(dev, dev->mem);
assert(r >= 0);
if (r < 0) {
VHOST_OPS_DEBUG("vhost_set_mem_table failed");
}
/* To log less, can only decrease log size after table update. */
if (dev->log_size > log_size + VHOST_LOG_BUFFER) {
vhost_dev_log_resize(dev, log_size);
@ -667,7 +686,7 @@ static int vhost_dev_set_features(struct vhost_dev *dev, bool enable_log)
static int vhost_dev_set_log(struct vhost_dev *dev, bool enable_log)
{
int r, t, i, idx;
int r, i, idx;
r = vhost_dev_set_features(dev, enable_log);
if (r < 0) {
goto err_features;
@ -684,12 +703,10 @@ static int vhost_dev_set_log(struct vhost_dev *dev, bool enable_log)
err_vq:
for (; i >= 0; --i) {
idx = dev->vhost_ops->vhost_get_vq_index(dev, dev->vq_index + i);
t = vhost_virtqueue_set_addr(dev, dev->vqs + i, idx,
dev->log_enabled);
assert(t >= 0);
vhost_virtqueue_set_addr(dev, dev->vqs + i, idx,
dev->log_enabled);
}
t = vhost_dev_set_features(dev, dev->log_enabled);
assert(t >= 0);
vhost_dev_set_features(dev, dev->log_enabled);
err_features:
return r;
}
@ -929,15 +946,11 @@ static void vhost_virtqueue_stop(struct vhost_dev *dev,
* native as legacy devices expect so by default.
*/
if (vhost_needs_vring_endian(vdev)) {
r = vhost_virtqueue_set_vring_endian_legacy(dev,
!virtio_is_big_endian(vdev),
vhost_vq_index);
if (r < 0) {
error_report("failed to reset vring endianness");
}
vhost_virtqueue_set_vring_endian_legacy(dev,
!virtio_is_big_endian(vdev),
vhost_vq_index);
}
assert (r >= 0);
cpu_physical_memory_unmap(vq->ring, virtio_queue_get_ring_size(vdev, idx),
0, virtio_queue_get_ring_size(vdev, idx));
cpu_physical_memory_unmap(vq->used, virtio_queue_get_used_size(vdev, idx),
@ -1228,7 +1241,9 @@ void vhost_virtqueue_mask(struct vhost_dev *hdev, VirtIODevice *vdev, int n,
file.index = hdev->vhost_ops->vhost_get_vq_index(hdev, n);
r = hdev->vhost_ops->vhost_set_vring_call(hdev, &file);
assert(r >= 0);
if (r < 0) {
VHOST_OPS_DEBUG("vhost_set_vring_call failed");
}
}
uint64_t vhost_get_features(struct vhost_dev *hdev, const int *feature_bits,