Commit graph

1,412,414 commits

Author SHA1 Message Date
Cindy Lu
719d959274 vdpa/mlx5: update mlx_features with driver state check
Add logic in mlx5_vdpa_set_attr() to ensure the VIRTIO_NET_F_MAC
feature bit is properly set only when the device is not yet in
the DRIVER_OK (running) state.

This makes the MAC address visible in the output of:

 vdpa dev config show -jp

when the device is created without an initial MAC address.

Signed-off-by: Cindy Lu <lulu@redhat.com>
Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260126094848.9601-2-lulu@redhat.com>
2026-02-04 14:13:43 -05:00
Bibo Mao
72ecf75c58 crypto: virtio: Replace package id with numa node id
With multiple virtio crypto devices supported with different NUMA
nodes, when crypto session is created, it will search virtio crypto
device with the same numa node of current CPU.

Here API topology_physical_package_id() is replaced with cpu_to_node()
since package id is physical concept, and one package id have multiple
memory numa id.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260113030556.3522533-4-maobibo@loongson.cn>
2026-01-28 15:32:18 -05:00
Bibo Mao
a389d43105 crypto: virtio: Remove duplicated virtqueue_kick in virtio_crypto_skcipher_crypt_req
With function virtio_crypto_skcipher_crypt_req(), there is already
virtqueue_kick() call with spinlock held in function
__virtio_crypto_skcipher_do_req(). Remove duplicated virtqueue_kick()
function call here.

Fixes: d79b5d0bbf ("crypto: virtio - support crypto engine framework")
Cc: stable@vger.kernel.org
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260113030556.3522533-3-maobibo@loongson.cn>
2026-01-28 15:32:18 -05:00
Bibo Mao
af9a17d29c crypto: virtio: Add spinlock protection with virtqueue notification
When VM boots with one virtio-crypto PCI device and builtin backend,
run openssl benchmark command with multiple processes, such as
  openssl speed -evp aes-128-cbc -engine afalg  -seconds 10 -multi 32

openssl processes will hangup and there is error reported like this:
 virtio_crypto virtio0: dataq.0:id 3 is not a head!

It seems that the data virtqueue need protection when it is handled
for virtio done notification. If the spinlock protection is added
in virtcrypto_done_task(), openssl benchmark with multiple processes
works well.

Fixes: fed93fb62e ("crypto: virtio - Handle dataq logic with tasklet")
Cc: stable@vger.kernel.org
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260113030556.3522533-2-maobibo@loongson.cn>
2026-01-28 15:32:18 -05:00
Eugenio Pérez
7a9dc249e7 Documentation: Add documentation for VDUSE Address Space IDs
Address Space IDs allows the VDUSE framework to support devices able to
expose different virtqueues to different part of the drivers.  For
example, to let QEMU handle the net device control virtqueue, so QEMU
always knows the state of the device like mac address or number of
queues enabled, while leaving the dataplane passthrough to the guest
intact.  This enables live migration.

Expands the VDUSE documentation to explain how to use the new ioctls or
the new struct members of old ioctls.

Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260119143306.1818855-14-eperezma@redhat.com>
2026-01-28 15:32:18 -05:00
Eugenio Pérez
12e0043d33 vduse: bump version number
Finalize the series by advertising VDUSE API v1 support to userspace.

Now that all required infrastructure for v1 (ASIDs, VQ groups,
update_iotlb_v2) is in place, VDUSE devices can opt in to the new
features.

Assume API version 0 if the VDUSE instance does not call
VDUSE_GET_API_VERSION to maintain compatibility.

Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260119143306.1818855-13-eperezma@redhat.com>
2026-01-28 15:32:18 -05:00
Eugenio Pérez
079212f687 vduse: add vq group asid support
Add support for assigning Address Space Identifiers (ASIDs) to each VQ
group.  This enables mapping each group into a distinct memory space.

The vq group to ASID association is protected by a rwlock now.  But the
mutex domain_lock keeps protecting the domains of all ASIDs, as some
operations like the one related with the bounce buffer size still
requires to lock all the ASIDs.

Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260119143306.1818855-12-eperezma@redhat.com>
2026-01-28 15:32:18 -05:00
Eugenio Pérez
f3dc3a8a3e vduse: merge tree search logic of IOTLB_GET_FD and IOTLB_GET_INFO ioctls
The next patch adds new ioctl with the ASID member per entry.  Abstract
these two so it can be build on top easily.

Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260119143306.1818855-11-eperezma@redhat.com>
2026-01-28 15:32:17 -05:00
Eugenio Pérez
489d765206 vduse: take out allocations from vduse_dev_alloc_coherent
The function vduse_dev_alloc_coherent will be called under rwlock in
next patches.  Make it out of the lock to avoid increasing its fail
rate.

Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260119143306.1818855-10-eperezma@redhat.com>
2026-01-28 15:32:17 -05:00
Eugenio Pérez
766e1749c0 vduse: remove unused vaddr parameter of vduse_domain_free_coherent
We will modify the function in next patches so let's clean it first.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260119143306.1818855-9-eperezma@redhat.com>
2026-01-28 15:32:17 -05:00
Eugenio Pérez
3e2ddda6f4 vduse: refactor vdpa_dev_add for goto err handling
Next patches introduce more error paths in this function.  Refactor it
so they can be accommodated through gotos.

Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Xie Yongji <xieyongji@bytedance.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260119143306.1818855-8-eperezma@redhat.com>
2026-01-28 15:32:17 -05:00
Eugenio Pérez
3543b04a4e vhost: forbid change vq groups ASID if DRIVER_OK is set
Only vdpa_sim support it.  Forbid this behaviour as there is no use for
it right now, we can always enable it in the future with a feature flag.

Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260119143306.1818855-7-eperezma@redhat.com>
2026-01-28 15:32:17 -05:00
Eugenio Pérez
0d215afdc8 vdpa: document set_group_asid thread safety
Document that the function races with the check of DRIVER_OK.

Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260119143306.1818855-6-eperezma@redhat.com>
2026-01-28 15:32:17 -05:00
Eugenio Pérez
02e3f7ffe2 vduse: return internal vq group struct as map token
Return the internal struct that represents the vq group as virtqueue map
token, instead of the device.  This allows the map functions to access
the information per group.

At this moment all the virtqueues share the same vq group, that only
can point to ASID 0.  This change prepares the infrastructure for actual
per-group address space handling

Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260119143306.1818855-5-eperezma@redhat.com>
2026-01-28 15:32:16 -05:00
Eugenio Pérez
9350a09afd vduse: add vq group support
This allows separate the different virtqueues in groups that shares the
same address space.  Asking the VDUSE device for the groups of the vq at
the beginning as they're needed for the DMA API.

Allocating 3 vq groups as net is the device that need the most groups:
* Dataplane (guest passthrough)
* CVQ
* Shadowed vrings.

Future versions of the series can include dynamic allocation of the
groups array so VDUSE can declare more groups.

Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Xie Yongji <xieyongji@bytedance.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260119143306.1818855-4-eperezma@redhat.com>
2026-01-28 15:32:16 -05:00
Eugenio Pérez
a006ed4ecd vduse: add v1 API definition
This allows the kernel to detect whether the userspace VDUSE device
supports the VQ group and ASID features.  VDUSE devices that don't set
the V1 API will not receive the new messages, and vdpa device will be
created with only one vq group and asid.

The next patches implement the new feature incrementally, only enabling
the VDUSE device to set the V1 API version by the end of the series.

Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Xie Yongji <xieyongji@bytedance.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260119143306.1818855-3-eperezma@redhat.com>
2026-01-28 15:32:16 -05:00
Eugenio Pérez
cd025c1e87 vhost: move vdpa group bound check to vhost_vdpa
Remove duplication by consolidating these here.  This reduces the
posibility of a parent driver missing them.

While we're at it, fix a bug in vdpa_sim where a valid ASID can be
assigned to a group equal to ngroups, causing an out of bound write.

Cc: stable@vger.kernel.org
Fixes: bda324fd03 ("vdpasim: control virtqueue support")
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260119143306.1818855-2-eperezma@redhat.com>
2026-01-28 15:32:16 -05:00
Michael S. Tsirkin
74bc5f69bd checkpatch: special-case cacheline group macros
Currently, cacheline group macros trigger checkpatch warnings.
For example:

  $ ./scripts/checkpatch.pl -g ba7e025a6c84aed012421468d83639e5dae982b0
  WARNING: Missing a blank line after declarations
  #58: FILE: drivers/gpio/gpio-virtio.c:32:
  +	struct virtio_gpio_response res;
  +	__dma_from_device_group_end();

  $ ./scripts/checkpatch.pl -g 5d4cc87414
  WARNING: Missing a blank line after declarations
  #267: FILE: include/net/sock.h:431:
  +	int			sk_rcvlowat;
  +	__cacheline_group_end(sock_read_rx);

But these are not actually statements - the following macros
all expand to zero-length fields:
  __cacheline_group_begin()
  __cacheline_group_end()
  __cacheline_group_begin_aligned()
  __cacheline_group_end_aligned()
  __dma_from_device_group_begin()
  __dma_from_device_group_end()

Add them to $declaration_macros so checkpatch recognizes this fact.

Message-ID: <b345bb7e2d4e23672e3e5d1b283754dc11c7d8cd.1767647872.git.mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2026-01-28 15:32:16 -05:00
Michael S. Tsirkin
1a266b6d9c gpio: virtio: reorder fields to reduce struct padding
Reorder struct virtio_gpio_line fields to place the DMA buffers
(req/res) last.

This eliminates the padding from aligning struct size on
ARCH_DMA_MINALIGN.

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Message-ID: <f1221bbc120df6adaba9006710a517f1e84a10b2.1767601130.git.mst@redhat.com>
Acked-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2026-01-28 15:32:16 -05:00
Michael S. Tsirkin
29615fe3fb gpio: virtio: fix DMA alignment
The res and ires buffers in struct virtio_gpio_line and struct
vgpio_irq_line respectively are used for DMA_FROM_DEVICE via
virtqueue_add_sgs().  However, within these structs, even though these
elements are tagged as ____cacheline_aligned, adjacent struct elements
can share DMA cachelines on platforms where ARCH_DMA_MINALIGN >
L1_CACHE_BYTES (e.g., arm64 with 128-byte DMA alignment but 64-byte
cache lines).

The existing ____cacheline_aligned annotation aligns to L1_CACHE_BYTES
which is not always sufficient for DMA alignment. For example, with
L1_CACHE_BYTES = 32 and ARCH_DMA_MINALIGN = 128
  - irq_lines[0].ires at offset 128
  - irq_lines[1].type at offset 192
both in same 128-byte DMA cacheline [128-256)

When the device writes to irq_lines[0].ires and the CPU concurrently
modifies one of irq_lines[1].type/disabled/masked/queued flags,
corruption can occur on non-cache-coherent platforms.

Fix by using __dma_from_device_group_begin()/end() annotations on the
DMA buffers. Drop ____cacheline_aligned - it's not required to isolate
request and response, and keeping them would increase the memory cost.

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Message-ID: <ba7e025a6c84aed012421468d83639e5dae982b0.1767601130.git.mst@redhat.com>
Acked-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2026-01-28 15:32:16 -05:00
Michael S. Tsirkin
f9108dee78 vsock/virtio: reorder fields to reduce padding
Reorder struct virtio_vsock fields to place the DMA buffer (event_list)
last. This eliminates the padding from aligning the struct size on
ARCH_DMA_MINALIGN.

Message-ID: <ce44f61af415521e00ab7492aa16d3d19f00bd5e.1769632071.git.mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2026-01-28 15:32:08 -05:00
Michael S. Tsirkin
d08fda2cf2 virtio_input: use virtqueue_add_inbuf_cache_clean for events
The evts array contains 64 small (8-byte) input events that share
cachelines with each other. When CONFIG_DMA_API_DEBUG is enabled,
this can trigger warnings about overlapping DMA mappings within
the same cacheline.

Previous patch isolated the array in its own cachelines,
so the warnings are now spurious.

Use virtqueue_add_inbuf_cache_clean() to indicate that the CPU does not
write into these cache lines, suppressing these warnings.

Message-ID: <4c885b4046323f68cf5cadc7fbfb00216b11dd20.1767601130.git.mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2026-01-08 09:54:27 -05:00
Michael S. Tsirkin
bd2b617c49 virtio-rng: fix DMA alignment for data buffer
The data buffer in struct virtrng_info is used for DMA_FROM_DEVICE via
virtqueue_add_inbuf() and shares cachelines with the adjacent
CPU-written fields (data_avail, data_idx).

The device writing to the DMA buffer and the CPU writing to adjacent
fields could corrupt each other's data on non-cache-coherent platforms.

Add __dma_from_device_group_begin()/end() annotations to place these
in distinct cache lines.

Message-ID: <157a63b6324d1f1307ddd4faa3b62a8b90a79423.1767601130.git.mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2026-01-08 09:54:27 -05:00
Michael S. Tsirkin
2678369e8e virtio_scsi: fix DMA cacheline issues for events
Current struct virtio_scsi_event_node layout has two problems:

The event (DMA_FROM_DEVICE) and work (CPU-written via
INIT_WORK/queue_work) fields share a cacheline.
On non-cache-coherent platforms, CPU writes to work can
corrupt device-written event data.

If ARCH_DMA_MINALIGN is large enough, the 8 events in event_list share
cachelines, triggering CONFIG_DMA_API_DEBUG warnings.

Fix the corruption by moving event buffers to a separate array and
aligning using __dma_from_device_group_begin()/end().

Suppress the (now spurious) DMA debug warnings using
virtqueue_add_inbuf_cache_clean().

Message-ID: <8801aeef7576a155299f19b6887682dd3a272aba.1767601130.git.mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2026-01-08 09:54:27 -05:00
Michael S. Tsirkin
95c7b0ad6c virtio_input: fix DMA alignment for evts
On non-cache-coherent platforms, when a structure contains a buffer
used for DMA alongside fields that the CPU writes to, cacheline sharing
can cause data corruption.

The evts array is used for DMA_FROM_DEVICE operations via
virtqueue_add_inbuf(). The adjacent lock and ready fields are written
by the CPU during normal operation. If these share cachelines with evts,
CPU writes can corrupt DMA data.

Add __dma_from_device_group_begin()/end() annotations to ensure evts is
isolated in its own cachelines.

Message-ID: <cd328233198a76618809bb5cd9a6ddcaa603a8a1.1767601130.git.mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2026-01-08 09:54:26 -05:00
Michael S. Tsirkin
db191ba0c8 vsock/virtio: use virtqueue_add_inbuf_cache_clean for events
The event_list array contains 8 small (4-byte) events that share
cachelines with each other. When CONFIG_DMA_API_DEBUG is enabled,
this can trigger warnings about overlapping DMA mappings within
the same cacheline.

The previous patch isolated event_list in its own cache lines
so the warnings are spurious.

Use virtqueue_add_inbuf_cache_clean() to indicate that the CPU does not
write into these fields, suppressing the warnings.

Reported-by: Cong Wang <xiyou.wangcong@gmail.com>
Message-ID: <4b5bf63a7ebb782d87f643466b3669df567c9fe1.1767601130.git.mst@redhat.com>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2026-01-08 09:54:26 -05:00
Michael S. Tsirkin
63dfad0517 vsock/virtio: fix DMA alignment for event_list
On non-cache-coherent platforms, when a structure contains a buffer
used for DMA alongside fields that the CPU writes to, cacheline sharing
can cause data corruption.

The event_list array is used for DMA_FROM_DEVICE operations via
virtqueue_add_inbuf(). The adjacent event_run and guest_cid fields are
written by the CPU while the buffer is available, so mapped for the
device. If these share cachelines with event_list, CPU writes can
corrupt DMA data.

Add __dma_from_device_group_begin()/end() annotations to ensure event_list
is isolated in its own cachelines.

Message-ID: <f19ebd74f70c91cab4b0178df78cf6a6e107a96b.1767601130.git.mst@redhat.com>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2026-01-08 09:54:19 -05:00
Michael S. Tsirkin
5fc6dd158e virtio: add virtqueue_add_inbuf_cache_clean API
Add virtqueue_add_inbuf_cache_clean() for passing DMA_ATTR_CPU_CACHE_CLEAN
to virtqueue operations. This suppresses DMA debug cacheline overlap
warnings for buffers where proper cache management is ensured by the
caller.

Message-ID: <e50d38c974859e731e50bda7a0ee5691debf5bc4.1767601130.git.mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2026-01-02 06:22:49 -05:00
Michael S. Tsirkin
d5d8465131 dma-debug: track cache clean flag in entries
If a driver is buggy and has 2 overlapping mappings but only
sets cache clean flag on the 1st one of them, we warn.
But if it only does it for the 2nd one, we don't.

Fix by tracking cache clean flag in the entry.

Message-ID: <0ffb3513d18614539c108b4548cdfbc64274a7d1.1767601130.git.mst@redhat.com>
Reviewed-by: Petr Tesarik <ptesarik@suse.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2026-01-02 06:22:49 -05:00
Michael S. Tsirkin
e21dd666e4 docs: dma-api: document DMA_ATTR_CPU_CACHE_CLEAN
Document DMA_ATTR_CPU_CACHE_CLEAN as implemented in the
previous patch.

Message-ID: <0720b4be31c1b7a38edca67fd0c97983d2a56936.1767601130.git.mst@redhat.com>
Reviewed-by: Petr Tesarik <ptesarik@suse.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2025-12-31 19:30:17 -05:00
Michael S. Tsirkin
61868dc55a dma-mapping: add DMA_ATTR_CPU_CACHE_CLEAN
When multiple small DMA_FROM_DEVICE or DMA_BIDIRECTIONAL buffers share a
cacheline, and DMA_API_DEBUG is enabled, we get this warning:
	cacheline tracking EEXIST, overlapping mappings aren't supported.

This is because when one of the mappings is removed, while another one
is active, CPU might write into the buffer.

Add an attribute for the driver to promise not to do this, making the
overlapping safe, and suppressing the warning.

Message-ID: <2d5d091f9d84b68ea96abd545b365dd1d00bbf48.1767601130.git.mst@redhat.com>
Reviewed-by: Petr Tesarik <ptesarik@suse.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2025-12-31 19:30:02 -05:00
Michael S. Tsirkin
1e8b5d8555 docs: dma-api: document __dma_from_device_group_begin()/end()
Document the __dma_from_device_group_begin()/end() annotations.

Message-ID: <01ea88055ded4d70cac70ba557680fd5fa7d9ff5.1767601130.git.mst@redhat.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Petr Tesarik <ptesarik@suse.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2025-12-31 19:28:12 -05:00
Michael S. Tsirkin
ca085faabb dma-mapping: add __dma_from_device_group_begin()/end()
When a structure contains a buffer that DMA writes to alongside fields
that the CPU writes to, cache line sharing between the DMA buffer and
CPU-written fields can cause data corruption on non-cache-coherent
platforms.

Add __dma_from_device_group_begin()/end() annotations to ensure proper
alignment to prevent this:

struct my_device {
	spinlock_t lock1;
	__dma_from_device_group_begin();
	char dma_buffer1[16];
	char dma_buffer2[16];
	__dma_from_device_group_end();
	spinlock_t lock2;
};

Message-ID: <19163086d5e4704c316f18f6da06bc1c72968904.1767601130.git.mst@redhat.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Petr Tesarik <ptesarik@suse.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2025-12-31 19:27:45 -05:00
Jason Wang
f6a15d8549 virtio_ring: add in order support
This patch implements in order support for both split virtqueue and
packed virtqueue. Performance could be gained for the device where the
memory access could be expensive (e.g vhost-net or a real PCI device):

Benchmark with KVM guest:

Vhost-net on the host: (pktgen + XDP_DROP):

         in_order=off | in_order=on | +%
    TX:  4.51Mpps     | 5.30Mpps    | +17%
    RX:  3.47Mpps     | 3.61Mpps    | + 4%

Vhost-user(testpmd) on the host: (pktgen/XDP_DROP):

For split virtqueue:

         in_order=off | in_order=on | +%
    TX:  5.60Mpps     | 5.60Mpps    | +0.0%
    RX:  9.16Mpps     | 9.61Mpps    | +4.9%

For packed virtqueue:

         in_order=off | in_order=on | +%
    TX:  5.60Mpps     | 5.70Mpps    | +1.7%
    RX:  10.6Mpps     | 10.8Mpps    | +1.8%

Benchmark also shows no performance impact for in_order=off for queue
size with 256 and 1024.

Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-20-jasowang@redhat.com>
2025-12-31 05:47:50 -05:00
Jason Wang
519b206e30 virtio_ring: factor out split detaching logic
This patch factors out the split core detaching logic that could be
reused by in order feature into a dedicated function.

Acked-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-19-jasowang@redhat.com>
2025-12-31 05:47:50 -05:00
Jason Wang
9dc6b944f1 virtio_ring: factor out split indirect detaching logic
Factor out the split indirect descriptor detaching logic in order to
allow it to be reused by the in order support.

Acked-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-18-jasowang@redhat.com>
2025-12-31 05:39:18 -05:00
Jason Wang
fa56d17b92 virtio_ring: factor out core logic for updating last_used_idx
Factor out the core logic for updating last_used_idx to be reused by
the packed in order implementation.

Acked-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-17-jasowang@redhat.com>
2025-12-31 05:39:18 -05:00
Jason Wang
c623106c79 virtio_ring: factor out core logic of buffer detaching
Factor out core logic of buffer detaching and leave the free list
management to the caller so in_order can just call the core logic.

Acked-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-16-jasowang@redhat.com>
2025-12-31 05:39:18 -05:00
Jason Wang
03f05c4eeb virtio_ring: determine descriptor flags at one time
Let's determine the last descriptor by counting the number of sg. This
would be consistent with packed virtqueue implementation and ease the
future in-order implementation.

Acked-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-15-jasowang@redhat.com>
2025-12-31 05:39:18 -05:00
Jason Wang
1208473f9b virtio_ring: introduce virtqueue ops
This patch introduces virtqueue ops which is a set of callbacks
that will be called for different queue layout or features. This would
help to avoid branches for split/packed and will ease the future
implementation like in order.

Note that in order to eliminate the indirect calls this patch uses
global array of const ops to allow compiler to avoid indirect
branches.

Tested with CONFIG_MITIGATION_RETPOLINE, no performance differences
were noticed.

Acked-by: Eugenio Pérez <eperezma@redhat.com>
Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-14-jasowang@redhat.com>
2025-12-31 05:39:18 -05:00
Jason Wang
eff8b47d28 virtio_ring: switch to use unsigned int for virtqueue_poll_packed()
Switch to use unsigned int for virtqueue_poll_packed() to match
virtqueue_poll() and virtqueue_poll_split() and to ease the
abstraction of the virtqueue ops.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-13-jasowang@redhat.com>
2025-12-31 05:39:18 -05:00
Jason Wang
f2ad9d6b4e virtio_ring: switch to use vring_virtqueue for detach_unused_buf variants
Those variants are used internally so let's switch to use
vring_virtqueue as parameter to be consistent with other internal
virtqueue helpers.

Acked-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-12-jasowang@redhat.com>
2025-12-31 05:39:18 -05:00
Jason Wang
7e81017673 virtio_ring: switch to use vring_virtqueue for disable_cb variants
Those variants are used internally so let's switch to use
vring_virtqueue as parameter to be consistent with other internal
virtqueue helpers.

Acked-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-11-jasowang@redhat.com>
2025-12-31 05:39:18 -05:00
Jason Wang
62fa22cdab virtio_ring: use vring_virtqueue for enable_cb_delayed variants
Those variants are used internally so let's switch to use
vring_virtqueue as parameter to be consistent with other internal
virtqueue helpers.

Acked-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-10-jasowang@redhat.com>
2025-12-31 05:39:18 -05:00
Jason Wang
74847cb573 virtio_ring: switch to use vring_virtqueue for enable_cb_prepare variants
Those variants are used internally so let's switch to use
vring_virtqueue as parameter to be consistent with other internal
virtqueue helpers.

Acked-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-9-jasowang@redhat.com>
2025-12-31 05:39:17 -05:00
Jason Wang
ceea1cd0ae virtio: switch to use vring_virtqueue for virtqueue_get variants
Those variants are used internally so let's switch to use
vring_virtqueue as parameter to be consistent with other internal
virtqueue helpers.

Acked-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-8-jasowang@redhat.com>
2025-12-31 05:39:17 -05:00
Jason Wang
4a0fa90b10 virtio_ring: switch to use vring_virtqueue for virtqueue_add variants
Those variants are used internally so let's switch to use
vring_virtqueue as parameter to be consistent with other internal
virtqueue helpers.

Acked-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-7-jasowang@redhat.com>
2025-12-31 05:39:17 -05:00
Jason Wang
8b8590b708 virtio_ring: switch to use vring_virtqueue for virtqueue_kick_prepare variants
Those variants are used internally so let's switch to use
vring_virtqueue as parameter to be consistent with other internal
virtqueue helpers.

Acked-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-6-jasowang@redhat.com>
2025-12-31 05:39:17 -05:00
Jason Wang
9552bc0581 virtio_ring: switch to use vring_virtqueue for virtqueue resize variants
Those variants are used internally so let's switch to use
vring_virtqueue as parameter to be consistent with other internal
virtqueue helpers.

Acked-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-5-jasowang@redhat.com>
2025-12-31 05:39:17 -05:00
Jason Wang
40da006f13 virtio_ring: unify logic of virtqueue_poll() and more_used()
This patch unifies the logic of virtqueue_poll() and more_used() for
better code reusing and ease the future in order implementation.

Acked-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-4-jasowang@redhat.com>
2025-12-31 05:39:17 -05:00