search for: pci_dma_read

...e <hw/block/block.h> #include <hw/hw.h> #include <hw/pci/msix.h> @@ -158,6 +159,14 @@ static uint16_t nvme_dma_read_prp(NvmeCtrl *n, uint8_t *ptr, uint32_t len, return NVME_SUCCESS; } +static void nvme_update_cq_head(NvmeCQueue *cq) +{ + if (cq->db_addr) { + pci_dma_read(&cq->ctrl->parent_obj, cq->db_addr, + &cq->head, sizeof(cq->head)); + } +} + static void nvme_post_cqes(void *opaque) { NvmeCQueue *cq = opaque; @@ -168,6 +177,8 @@ static void nvme_post_cqes(void *opaque) NvmeSQueue *sq; hwaddr...

Hi Rob & Mihai, I wrote vhost-nvme patches on top of Christoph's NVMe target. vhost-nvme still uses mmio. So the guest OS can run unmodified NVMe driver. But the tests I have done didn't show competitive performance compared to virtio-blk/virtio-scsi. The bottleneck is in mmio. Your nvme vendor extension patches reduces greatly the number of MMIO writes. So I'd like to push it

Hi Rob & Mihai, I wrote vhost-nvme patches on top of Christoph's NVMe target. vhost-nvme still uses mmio. So the guest OS can run unmodified NVMe driver. But the tests I have done didn't show competitive performance compared to virtio-blk/virtio-scsi. The bottleneck is in mmio. Your nvme vendor extension patches reduces greatly the number of MMIO writes. So I'd like to push it