[PATCH v7 00/26] virtio pci support VIRTIO_F_RING_RESET

Xuan Zhuo
2022-03-08T12:35:29Z

The virtio spec already supports the virtio queue reset function. This patch set
is to add this function to the kernel. The relevant virtio spec information is
here:

https://github.com/oasis-tcs/virtio-spec/issues/124

Also regarding MMIO support for queue reset, I plan to support it after this
patch is passed.

Performing reset on a queue is divided into four steps:
1. virtio_reset_vq() - notify the device to reset the queue
2. virtqueue_detach_unused_buf() - recycle the buffer submitted
3. virtqueue_reset_vring() - reset the vring (may re-alloc)
4. virtio_enable_resetq() - mmap vring to device, and enable the queue

The first part 1-17 of this patch set implements virtio pci's support and API
for queue reset. The latter part is to make virtio-net support set_ringparam. Do
these things for this feature:

1. virtio-net support rx,tx reset
2. find_vqs() support to special the max size of each vq
3. virtio-net support set_ringparam

#1 -#3 : prepare
#4 -#12: virtio ring support reset vring of the vq
#13-#14: add helper
#15-#17: virtio pci support reset queue and re-enable
#18-#21: find_vqs() support sizes to special the max size of each vq
#23-#24: virtio-net support rx, tx reset
#22, #25, #26: virtio-net support set ringparam

Test environment:
Host: 4.19.91
Qemu: QEMU emulator version 6.2.50 (with vq reset support)
Test Cmd: ethtool -G eth1 rx $1 tx $2; ethtool -g eth1

The default is split mode, modify Qemu virtio-net to add PACKED feature to test
packed mode.

Please review. Thanks.

v7:
1. fix #6 subject typo
2. fix #6 ring_size_in_bytes is uninitialized
3. check by: make W=12

v6:
1. virtio_pci: use synchronize_irq(irq) to sync the irq callbacks
2. Introduce virtqueue_reset_vring() to implement the reset of vring during
the reset process. May use the old vring if num of the vq not change.
3. find_vqs() support sizes to special the max size of each vq

v5:
1. add virtio-net support set_ringparam

v4:
1. just the code of virtio, without virtio-net
2. Performing reset on a queue is divided into these steps:
1. reset_vq: reset one vq
2. recycle the buffer from vq by virtqueue_detach_unused_buf()
3. release the ring of the vq by vring_release_virtqueue()
4. enable_reset_vq: re-enable the reset queue
3. Simplify the parameters of enable_reset_vq()
4. add container structures for virtio_pci_common_cfg

v3:
1. keep vq, irq unreleased

*** BLURB HERE ***

Xuan Zhuo (26):
virtio_pci: struct virtio_pci_common_cfg add queue_notify_data
virtio: queue_reset: add VIRTIO_F_RING_RESET
virtio: add helper virtqueue_get_vring_max_size()
virtio_ring: split: extract the logic of creating vring
virtio_ring: split: extract the logic of init vq and attach vring
virtio_ring: packed: extract the logic of creating vring
virtio_ring: packed: extract the logic of init vq and attach vring
virtio_ring: extract the logic of freeing vring
virtio_ring: split: implement virtqueue_reset_vring_split()
virtio_ring: packed: implement virtqueue_reset_vring_packed()
virtio_ring: introduce virtqueue_reset_vring()
virtio_ring: update the document of the virtqueue_detach_unused_buf
for queue reset
virtio: queue_reset: struct virtio_config_ops add callbacks for
queue_reset
virtio: add helper for queue reset
virtio_pci: queue_reset: update struct virtio_pci_common_cfg and
option functions
virtio_pci: queue_reset: extract the logic of active vq for modern pci
virtio_pci: queue_reset: support VIRTIO_F_RING_RESET
virtio: find_vqs() add arg sizes
virtio_pci: support the arg sizes of find_vqs()
virtio_mmio: support the arg sizes of find_vqs()
virtio: add helper virtio_find_vqs_ctx_size()
virtio_net: get ringparam by virtqueue_get_vring_max_size()
virtio_net: split free_unused_bufs()
virtio_net: support rx/tx queue reset
virtio_net: set the default max ring size by find_vqs()
virtio_net: support set_ringparam

arch/um/drivers/virtio_uml.c | 2 +-
drivers/net/virtio_net.c | 257 ++++++++--
drivers/platform/mellanox/mlxbf-tmfifo.c | 3 +-
drivers/remoteproc/remoteproc_virtio.c | 2 +-
drivers/s390/virtio/virtio_ccw.c | 2 +-
drivers/virtio/virtio_mmio.c | 12 +-
drivers/virtio/virtio_pci_common.c | 28 +-
drivers/virtio/virtio_pci_common.h | 3 +-
drivers/virtio/virtio_pci_legacy.c | 8 +-
drivers/virtio/virtio_pci_modern.c | 146 +++++-
drivers/virtio/virtio_pci_modern_dev.c | 36 ++
drivers/virtio/virtio_ring.c | 584 +++++++++++++++++------
drivers/virtio/virtio_vdpa.c | 2 +-
include/linux/virtio.h | 12 +
include/linux/virtio_config.h | 74 ++-
include/linux/virtio_pci_modern.h | 2 +
include/uapi/linux/virtio_config.h | 7 +-
include/uapi/linux/virtio_pci.h | 14 +
18 files changed, 979 insertions(+), 215 deletions(-)

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2.31.0