+Markus
On 8/27/21 7:48 AM, Klaus Jensen wrote:
> On Aug 26 21:50, Philippe Mathieu-Daudé wrote:
>> Currently qemu_vfio_dma_map() displays errors on stderr.
>> When using management interface, this information is simply
>> lost. Pass qemu_vfio_dma_map() an Error** handle so it can
>> propagate the error to callers.
>>
>> Reviewed-by: Fam Zheng <f...@euphon.net>
>> Reviewed-by: Stefan Hajnoczi <stefa...@redhat.com>
>> Signed-off-by: Philippe Mathieu-Daudé <phi...@redhat.com>
>> ---
>> include/qemu/vfio-helpers.h | 2 +-
>> block/nvme.c | 22 +++++++++++-----------
>> util/vfio-helpers.c | 10 ++++++----
>> 3 files changed, 18 insertions(+), 16 deletions(-)
>>
>> diff --git a/include/qemu/vfio-helpers.h b/include/qemu/vfio-helpers.h
>> index 4491c8e1a6e..bde9495b254 100644
>> --- a/include/qemu/vfio-helpers.h
>> +++ b/include/qemu/vfio-helpers.h
>> @@ -18,7 +18,7 @@ typedef struct QEMUVFIOState QEMUVFIOState;
>> QEMUVFIOState *qemu_vfio_open_pci(const char *device, Error **errp);
>> void qemu_vfio_close(QEMUVFIOState *s);
>> int qemu_vfio_dma_map(QEMUVFIOState *s, void *host, size_t size,
>> - bool temporary, uint64_t *iova_list);
>> + bool temporary, uint64_t *iova_list, Error **errp);
>> int qemu_vfio_dma_reset_temporary(QEMUVFIOState *s);
>> void qemu_vfio_dma_unmap(QEMUVFIOState *s, void *host);
>> void *qemu_vfio_pci_map_bar(QEMUVFIOState *s, int index,
>> diff --git a/block/nvme.c b/block/nvme.c
>> index 0786c501e46..80546b0babd 100644
>> --- a/block/nvme.c
>> +++ b/block/nvme.c
>> @@ -176,12 +176,11 @@ static bool nvme_init_queue(BDRVNVMeState *s,
>> NVMeQueue *q,
>> return false;
>> }
>> memset(q->queue, 0, bytes);
>> - r = qemu_vfio_dma_map(s->vfio, q->queue, bytes, false, &q->iova);
>> + r = qemu_vfio_dma_map(s->vfio, q->queue, bytes, false, &q->iova, errp);
>> if (r) {
>> - error_setg(errp, "Cannot map queue");
>> - return false;
>> + error_prepend(errp, "Cannot map queue: ");
>> }
>> - return true;
>> + return r == 0;
>> }
>>
>> static void nvme_free_queue_pair(NVMeQueuePair *q)
>> @@ -239,9 +238,9 @@ static NVMeQueuePair
>> *nvme_create_queue_pair(BDRVNVMeState *s,
>> qemu_co_queue_init(&q->free_req_queue);
>> q->completion_bh = aio_bh_new(aio_context, nvme_process_completion_bh,
>> q);
>> r = qemu_vfio_dma_map(s->vfio, q->prp_list_pages, bytes,
>> - false, &prp_list_iova);
>> + false, &prp_list_iova, errp);
>> if (r) {
>> - error_setg_errno(errp, -r, "Cannot map buffer for DMA");
>> + error_prepend(errp, "Cannot map buffer for DMA: ");
>> goto fail;
>> }
>> q->free_req_head = -1;
>> @@ -534,9 +533,9 @@ static bool nvme_identify(BlockDriverState *bs, int
>> namespace, Error **errp)
>> error_setg(errp, "Cannot allocate buffer for identify response");
>> goto out;
>> }
>> - r = qemu_vfio_dma_map(s->vfio, id, id_size, true, &iova);
>> + r = qemu_vfio_dma_map(s->vfio, id, id_size, true, &iova, errp);
>> if (r) {
>> - error_setg(errp, "Cannot map buffer for DMA");
>> + error_prepend(errp, "Cannot map buffer for DMA: ");
>> goto out;
>> }
>>
>> @@ -1032,7 +1031,7 @@ static coroutine_fn int
>> nvme_cmd_map_qiov(BlockDriverState *bs, NvmeCmd *cmd,
>> try_map:
>> r = qemu_vfio_dma_map(s->vfio,
>> qiov->iov[i].iov_base,
>> - len, true, &iova);
>> + len, true, &iova, NULL);
>> if (r == -ENOSPC) {
>> /*
>> * In addition to the -ENOMEM error, the VFIO_IOMMU_MAP_DMA
>> @@ -1524,14 +1523,15 @@ static void nvme_aio_unplug(BlockDriverState *bs)
>> static void nvme_register_buf(BlockDriverState *bs, void *host, size_t size)
>> {
>> int ret;
>> + Error *local_err = NULL;
>> BDRVNVMeState *s = bs->opaque;
>>
>> - ret = qemu_vfio_dma_map(s->vfio, host, size, false, NULL);
>> + ret = qemu_vfio_dma_map(s->vfio, host, size, false, NULL, &local_err);
>> if (ret) {
>> /* FIXME: we may run out of IOVA addresses after repeated
>> * bdrv_register_buf/bdrv_unregister_buf, because
>> nvme_vfio_dma_unmap
>> * doesn't reclaim addresses for fixed mappings. */
>> - error_report("nvme_register_buf failed: %s", strerror(-ret));
>> + error_reportf_err(local_err, "nvme_register_buf failed: ");
>> }
>> }
>>
>> diff --git a/util/vfio-helpers.c b/util/vfio-helpers.c
>> index e7909222cfd..77cdec845d9 100644
>> --- a/util/vfio-helpers.c
>> +++ b/util/vfio-helpers.c
>> @@ -463,13 +463,15 @@ static void qemu_vfio_ram_block_added(RAMBlockNotifier
>> *n, void *host,
>> size_t size, size_t max_size)
>> {
>> QEMUVFIOState *s = container_of(n, QEMUVFIOState, ram_notifier);
>> + Error *local_err = NULL;
>> int ret;
>>
>> trace_qemu_vfio_ram_block_added(s, host, max_size);
>> - ret = qemu_vfio_dma_map(s, host, max_size, false, NULL);
>> + ret = qemu_vfio_dma_map(s, host, max_size, false, NULL, &local_err);
>> if (ret) {
>> - error_report("qemu_vfio_dma_map(%p, %zu) failed: %s", host,
>> max_size,
>> - strerror(-ret));
>> + error_reportf_err(local_err,
>> + "qemu_vfio_dma_map(%p, %zu) failed: ",
>> + host, max_size);
>> }
>> }
>>
>> @@ -725,7 +727,7 @@ qemu_vfio_find_temp_iova(QEMUVFIOState *s, size_t size,
>> uint64_t *iova)
>> * mapping status within this area is not allowed).
>> */
>> int qemu_vfio_dma_map(QEMUVFIOState *s, void *host, size_t size,
>> - bool temporary, uint64_t *iova)
>> + bool temporary, uint64_t *iova, Error **errp)
>
> Won't this break at this point? You add an Error** to qemu_vfio_dma_map,
> but it is never used (so it probably stays NULL). So, above, if
> qemu_vfio_dma_map() returns something not zero, you use error_prepend(),
> which I think expects errp to be non-NULL?
I can't find such restriction documented in "qapi/error.h".
In error.c:
void error_prepend(Error *const *errp, const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
error_vprepend(errp, fmt, ap);
...
void error_vprepend(Error *const *errp, const char *fmt, va_list ap)
{
GString *newmsg;
if (!errp) {
return;
}
...
>
> I realize that later patches fixes this, but this sticks out when
> reviewing this on its own.
>
>> {
>> int ret = 0;
>> int index;
>> --
>> 2.31.1
>>
>>
>
