kernel/linux.git/include/linux/virtio_ring.h, branch v6.6.132

virtio_ring: add a struct device forward declaration

2023-04-21T07:02:35+00:00

The virtio_ring header file uses the struct device without a forward declaration. Signed-off-by: Shunsuke Mie Message-Id: <20230417022037.917668-1-mie@igel.co.jp> Signed-off-by: Michael S. Tsirkin

virtio: add VIRTIO_F_NOTIFICATION_DATA feature support

2023-04-21T07:02:35+00:00

According to VirtIO spec v1.2, VIRTIO_F_NOTIFICATION_DATA feature indicates that the driver passes extra data along with the queue notifications. In a split queue case, the extra data is 16-bit available index. In a packed queue case, the extra data is 1-bit wrap counter and 15-bit available index. Add support for this feature for MMIO, channel I/O and modern PCI transports. Signed-off-by: Viktor Prutyanov Acked-by: Jason Wang Reviewed-by: Xuan Zhuo Message-Id: <20230413081855.36643-2-alvaro.karsz@solid-run.com> Signed-off-by: Michael S. Tsirkin

virtio_ring: per virtqueue dma device

2023-02-21T00:26:58+00:00

This patch introduces a per virtqueue dma device. This will be used for virtio devices whose virtqueue are backed by different underlayer devices. One example is the vDPA that where the control virtqueue could be implemented through software mediation. Some of the work are actually done before since the helper like vring_dma_device(). This work left are: - Let vring_dma_device() return the per virtqueue dma device instead of the vdev's parent. - Allow passing a dma_device when creating the virtqueue through a new helper, old vring creation helper will keep using vdev's parent. Reviewed-by: Eli Cohen Tested-by: Eli Cohen Signed-off-by: Jason Wang Message-Id: <20230119061525.75068-2-jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin

virtio_ring: split: stop __vring_new_virtqueue as export symbol

2022-08-11T08:06:38+00:00

There is currently only one place to reference __vring_new_virtqueue() directly from the outside of virtio core. And here vring_new_virtqueue() can be used instead. Subsequent patches will modify __vring_new_virtqueue, so stop it as an export symbol for now. Signed-off-by: Xuan Zhuo Acked-by: Jason Wang Message-Id: <20220801063902.129329-8-xuanzhuo@linux.alibaba.com> Signed-off-by: Michael S. Tsirkin

virtio_ring: sparse warning fixup

2020-08-05T13:30:19+00:00

virtio_store_mb was built with split ring in mind so it accepts __virtio16 arguments. Packed ring uses __le16 values, so sparse complains. It's just a store with some barriers so let's convert it to a macro, we don't loose too much type safety by doing that. Signed-off-by: Michael S. Tsirkin Acked-by: Cornelia Huck

virtio: Honour 'may_reduce_num' in vring_create_virtqueue

2019-04-08T21:05:52+00:00

vring_create_virtqueue() allows the caller to specify via the may_reduce_num parameter whether the vring code is allowed to allocate a smaller ring than specified. However, the split ring allocation code tries to allocate a smaller ring on allocation failure regardless of what the caller specified. This may cause trouble for e.g. virtio-pci in legacy mode, which does not support ring resizing. (The packed ring code does not resize in any case.) Let's fix this by bailing out immediately in the split ring code if the requested size cannot be allocated and may_reduce_num has not been specified. While at it, fix a typo in the usage instructions. Fixes: 2a2d1382fe9d ("virtio: Add improved queue allocation API") Cc: stable@vger.kernel.org # v4.6+ Signed-off-by: Cornelia Huck Signed-off-by: Michael S. Tsirkin Reviewed-by: Halil Pasic Reviewed-by: Jens Freimann

virtio_ring: switch to dma_XX barriers for rpmsg

2018-06-07T17:54:23+00:00

virtio is using barriers to order memory accesses, thus dma_wmb/rmb is a good match. Before [mst@tuck linux]$ size drivers/virtio/virtio_ring.o text data bss dec hex filename 11392 820 0 12212 2fb4 drivers/virtio/virtio_ring.o After mst@tuck linux]$ size drivers/virtio/virtio_ring.o text data bss dec hex filename 11284 820 0 12104 2f48 drivers/virtio/virtio_ring.o Cc: Ohad Ben-Cohen Cc: Bjorn Andersson Cc: linux-remoteproc@vger.kernel.org Signed-off-by: Michael S. Tsirkin

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55+00:00

Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

virtio: add context flag to find vqs

2017-05-02T20:41:43+00:00

Allows maintaining extra context per vq. For ease of use, passing in NULL is legal and disables the feature for all vqs. Includes fixes by Christian for s390, acked by Cornelia. Signed-off-by: Christian Borntraeger Acked-by: Cornelia Huck Signed-off-by: Michael S. Tsirkin

virtio: Add improved queue allocation API

2016-03-02T15:01:57+00:00

This leaves vring_new_virtqueue alone for compatbility, but it adds two new improved APIs: vring_create_virtqueue: Creates a virtqueue backed by automatically allocated coherent memory. (Some day it this could be extended to support non-coherent memory, too, if there ends up being a platform on which it's worthwhile.) __vring_new_virtqueue: Creates a virtqueue with a manually-specified layout. This should allow mic_virtio to work much more cleanly. Signed-off-by: Andy Lutomirski Signed-off-by: Michael S. Tsirkin