linux-next.git/include/linux/virtio_caif.h, branch master

caif: remove CAIF NETWORK LAYER

2026-04-23T17:23:44+00:00

Remove CAIF (Communication CPU to Application CPU Interface), the ST-Ericsson modem protocol. The subsystem has been orphaned since 2013. The last meaningful changes from the maintainers were in March 2013: a8c7687bf216 ("caif_virtio: Check that vringh_config is not null") b2273be8d2df ("caif_virtio: Use vringh_notify_enable correctly") 0d2e1a2926b1 ("caif_virtio: Introduce caif over virtio") Not-so-coincidentally, according to "the Internet" ST-Ericsson officially shut down its modem joint venture in Aug 2013. If anyone is using this code please yell! In the 13 years since, the code has accumulated 200 non-merge commits, of which 71 were cross-tree API changes, 21 carried Fixes: tags, and the remaining ~110 were cleanups, doc conversions, treewide refactors, and one partial removal (caif_hsi, ca75bcf0a83b). We are still getting fixes to this code, in the last 10 days there were 3 reports on security@ about CAIF that I have been CCed on. UAPI constants (AF_CAIF, ARPHRD_CAIF, N_CAIF, VIRTIO_ID_CAIF) and the SELinux classmap entry are intentionally kept for ABI stability. Acked-by: Michael S. Tsirkin Acked-by: Greg Kroah-Hartman Reviewed-by: Linus Walleij Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260416182829.1440262-1-kuba@kernel.org Signed-off-by: Jakub Kicinski

virtio_caif: correct tags for config space fields

2020-08-05T15:08:41+00:00

Tag config space fields as having virtio endian-ness. Signed-off-by: Michael S. Tsirkin

caif_virtio: Introduce caif over virtio

2013-03-20T03:36:06+00:00

Add the CAIF Virtio shared memory driver for talking to a modem. This CAIF Link layer communicates to the modem over shared memory. It is implemented as a virtio_driver. The underlying virtio device is managed by the remoteproc framework. The Virtio queue is used for transmitting data to the modem, and the new vringh is used for receiving data. Genalloc is used for managing the shared memory used for TX data. The default dma-alloc-coherent allocator can only allocate whole pages, and this wastes too much shared memory. Flow control is implemented by stopping the TX-queues if the virtio queues go full or we run out of memory. Queued are reopened when queues are below the watermark. NAPI is used in RX path, and a dedicated tasklet is used for releasing TX buffers. Signed-off-by: Erwan Yvin Acked-by: David S. Miller Signed-off-by: Rusty Russell (minor fixes)