linux.git/drivers/virtio/virtio_ring.c, branch for-next

virtio_ring: add a func argument 'recycle_done' to virtqueue_reset()

2024-12-10T10:22:21+00:00

When virtqueue_reset() has actually recycled all unused buffers,
additional work may be required in some cases. Relying solely on its
return status is fragile, so introduce a new function argument
'recycle_done', which is invoked when it really occurs.

Signed-off-by: Koichiro Den 
Acked-by: Jason Wang 
Reviewed-by: Xuan Zhuo 
Signed-off-by: Paolo Abeni

virtio_ring: add a func argument 'recycle_done' to virtqueue_resize()

2024-12-10T10:22:21+00:00

When virtqueue_resize() has actually recycled all unused buffers,
additional work may be required in some cases. Relying solely on its
return status is fragile, so introduce a new function argument
'recycle_done', which is invoked when the recycle really occurs.

Cc:  # v6.11+
Signed-off-by: Koichiro Den 
Acked-by: Jason Wang 
Reviewed-by: Xuan Zhuo 
Signed-off-by: Paolo Abeni

Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

2024-11-27T21:11:58+00:00

Pull virtio updates from Michael Tsirkin:
 "A small number of improvements all over the place"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio_vdpa: remove redundant check on desc
  virtio_fs: store actual queue index in mq_map
  virtio_fs: add informative log for new tag discovery
  virtio: Make vring_new_virtqueue support packed vring
  virtio_pmem: Add freeze/restore callbacks
  vdpa/mlx5: Fix suboptimal range on iotlb iteration

virtio_ring: remove API virtqueue_set_dma_premapped

2024-11-16T02:46:55+00:00

Now, this API is useless. remove it.

Signed-off-by: Xuan Zhuo 
Acked-by: Jason Wang 
Link: https://patch.msgid.link/20241112012928.102478-8-xuanzhuo@linux.alibaba.com
Signed-off-by: Jakub Kicinski

virtio_ring: introduce add api for premapped

2024-11-16T02:46:55+00:00

Two APIs are introduced to submit premapped per-buffers.

int virtqueue_add_inbuf_premapped(struct virtqueue *vq,
                                 struct scatterlist *sg, unsigned int num,
                                 void *data,
                                 void *ctx,
                                 gfp_t gfp);

int virtqueue_add_outbuf_premapped(struct virtqueue *vq,
                                  struct scatterlist *sg, unsigned int num,
                                  void *data,
                                  gfp_t gfp);

Signed-off-by: Xuan Zhuo 
Acked-by: Jason Wang 
Link: https://patch.msgid.link/20241112012928.102478-6-xuanzhuo@linux.alibaba.com
Signed-off-by: Jakub Kicinski

virtio_ring: perform premapped operations based on per-buffer

2024-11-16T02:46:55+00:00

The current configuration sets the virtqueue (vq) to premapped mode,
implying that all buffers submitted to this queue must be mapped ahead
of time. This presents a challenge for the virtnet send queue (sq): the
virtnet driver would be required to keep track of dma information for vq
size * 17, which can be substantial. However, if the premapped mode were
applied on a per-buffer basis, the complexity would be greatly reduced.
With AF_XDP enabled, AF_XDP buffers would become premapped, while kernel
skb buffers could remain unmapped.

And consider that some sgs are not generated by the virtio driver,
that may be passed from the block stack. So we can not change the
sgs, new APIs are the better way.

So we pass the new argument 'premapped' to indicate the buffers
submitted to virtio are premapped in advance. Additionally,
DMA unmap operations for these buffers will be bypassed.

Suggested-by: Jason Wang 
Signed-off-by: Xuan Zhuo 
Acked-by: Jason Wang 
Link: https://patch.msgid.link/20241112012928.102478-5-xuanzhuo@linux.alibaba.com
Signed-off-by: Jakub Kicinski

virtio_ring: packed: record extras for indirect buffers

2024-11-16T02:46:54+00:00

The subsequent commit needs to know whether every indirect buffer is
premapped or not. So we need to introduce an extra struct for every
indirect buffer to record this info.

Signed-off-by: Xuan Zhuo 
Acked-by: Jason Wang 
Link: https://patch.msgid.link/20241112012928.102478-4-xuanzhuo@linux.alibaba.com
Signed-off-by: Jakub Kicinski

virtio_ring: split: record extras for indirect buffers

2024-11-16T02:46:54+00:00

The subsequent commit needs to know whether every indirect buffer is
premapped or not. So we need to introduce an extra struct for every
indirect buffer to record this info.

Signed-off-by: Xuan Zhuo 
Acked-by: Jason Wang 
Link: https://patch.msgid.link/20241112012928.102478-3-xuanzhuo@linux.alibaba.com
Signed-off-by: Jakub Kicinski

virtio_ring: introduce vring_need_unmap_buffer

2024-11-16T02:46:54+00:00

To make the code readable, introduce vring_need_unmap_buffer() to
replace do_unmap.

   use_dma_api premapped -> vring_need_unmap_buffer()
1. false       false        false
2. true        false        true
3. true        true         false

Signed-off-by: Xuan Zhuo 
Acked-by: Jason Wang 
Link: https://patch.msgid.link/20241112012928.102478-2-xuanzhuo@linux.alibaba.com
Signed-off-by: Jakub Kicinski

virtio: Make vring_new_virtqueue support packed vring

2024-11-12T23:07:24+00:00

It is used for testing in tools/virtio/vringh_test.c.
If vring_new_virtqueue supports packed vring, we can add support for
packed vring to vringh and test it.

Signed-off-by: Wenyu Huang 
Message-Id: <20241013033233.65026-1-huangwenyu1998@gmail.com>
Signed-off-by: Michael S. Tsirkin 
Reviewed-by: Stefano Garzarella 
Acked-by: Jason Wang