linux/Documentation/userspace-api/ioctl, branch v5.17

xen: update missing ioctl magic numers documentation

2022-02-03T07:24:34Z

Add missing ioctl "magic numbers" for various Xen interfaces (xenbus_dev.h, gntalloc.h, gntdev.h, and privcmd.h). Signed-off-by: Randy Dunlap Reviewed-by: Juergen Gross Cc: Boris Ostrovsky Cc: Juergen Gross Cc: Stefano Stabellini Cc: xen-devel@lists.xenproject.org Link: https://lore.kernel.org/r/20220131161959.16509-1-rdunlap@infradead.org Signed-off-by: Juergen Gross

ACPI: Introduce Platform Firmware Runtime Update device driver

2021-12-27T16:12:58Z

Introduce the pfr_update driver which can be used for Platform Firmware Runtime code injection and driver update [1]. The user is expected to provide the EFI capsule, and pass it to the driver by writing the capsule to a device special file. The capsule is transferred by the driver to the platform firmware with the help of an ACPI _DSM method under the special ACPI Platform Firmware Runtime Update device (INTC1080), and the actual firmware update is carried out by the low-level Management Mode code in the platform firmware. This change allows certain pieces of the platform firmware to be updated on the fly while the system is running (runtime) without the need to restart it, which is key in the cases when the system needs to be available 100% of the time and it cannot afford the downtime related to restarting it, or when the work carried out by the system is particularly important, so it cannot be interrupted, and it is not practical to wait until it is complete. Link: https://uefi.org/sites/default/files/resources/Intel_MM_OS_Interface_Spec_Rev100.pdf # [1] Tested-by: Hongyu Ning Signed-off-by: Chen Yu [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki

Merge tag 'char-misc-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2021-11-04T15:21:47Z

Pull char/misc driver updates from Greg KH: "Here is the big set of char and misc and other tiny driver subsystem updates for 5.16-rc1. Loads of things in here, all of which have been in linux-next for a while with no reported problems (except for one called out below.) Included are: - habanana labs driver updates, including dma_buf usage, reviewed and acked by the dma_buf maintainers - iio driver update (going through this tree not staging as they really do not belong going through that tree anymore) - counter driver updates - hwmon driver updates that the counter drivers needed, acked by the hwmon maintainer - xillybus driver updates - binder driver updates - extcon driver updates - dma_buf module namespaces added (will cause a build error in arm64 for allmodconfig, but that change is on its way through the drm tree) - lkdtm driver updates - pvpanic driver updates - phy driver updates - virt acrn and nitr_enclaves driver updates - smaller char and misc driver updates" * tag 'char-misc-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (386 commits) comedi: dt9812: fix DMA buffers on stack comedi: ni_usb6501: fix NULL-deref in command paths arm64: errata: Enable TRBE workaround for write to out-of-range address arm64: errata: Enable workaround for TRBE overwrite in FILL mode coresight: trbe: Work around write to out of range coresight: trbe: Make sure we have enough space coresight: trbe: Add a helper to determine the minimum buffer size coresight: trbe: Workaround TRBE errata overwrite in FILL mode coresight: trbe: Add infrastructure for Errata handling coresight: trbe: Allow driver to choose a different alignment coresight: trbe: Decouple buffer base from the hardware base coresight: trbe: Add a helper to pad a given buffer area coresight: trbe: Add a helper to calculate the trace generated coresight: trbe: Defer the probe on offline CPUs coresight: trbe: Fix incorrect access of the sink specific data coresight: etm4x: Add ETM PID for Kryo-5XX coresight: trbe: Prohibit trace before disabling TRBE coresight: trbe: End the AUX handle on truncation coresight: trbe: Do not truncate buffer on IRQ coresight: trbe: Fix handling of spurious interrupts ...

Merge tag 'for-5.16/cdrom-2021-10-29' of git://git.kernel.dk/linux-block

2021-11-01T17:09:14Z

Pull CDROM updates from Jens Axboe: "On behalf of Phillip, here are the CDROM updates for the 5.16-rc1 merge window: - Add ioctl for improved media change detection (Lukas) - Reformat some documentation (Phillip) - Redundant variable removal (luo)" * tag 'for-5.16/cdrom-2021-10-29' of git://git.kernel.dk/linux-block: cdrom: Remove redundant variable and its assignment cdrom: docs: reformat table in Documentation/userspace-api/ioctl/cdrom.rst drivers/cdrom: improved ioctl for media change detection

ptp: Document the PTP_CLK_MAGIC ioctl number

2021-10-28T00:02:51Z

Add PTP_CLK_MAGIC to the userspace-api/ioctl/ioctl-number.rst documentation file. Fixes: d94ba80ebbea ("ptp: Added a brand new class driver for ptp clocks.") Signed-off-by: Randy Dunlap Cc: Richard Cochran Cc: John Stultz Cc: Jonathan Corbet Link: https://lore.kernel.org/r/20211024163831.10200-1-rdunlap@infradead.org Signed-off-by: Jakub Kicinski

docs: counter: Document character device interface

2021-10-17T09:54:04Z

This patch adds high-level documentation about the Counter subsystem character device interface. Signed-off-by: William Breathitt Gray Link: https://lore.kernel.org/r/7a71dff2868195901d074ae2ec1b5611838d4b24.1632884256.git.vilhelm.gray@gmail.com Signed-off-by: Jonathan Cameron

cdrom: docs: reformat table in Documentation/userspace-api/ioctl/cdrom.rst

2021-10-11T01:35:37Z

Add extra space to the first column of ioctl values table, and also realign the text in the second column, to fix a documentation build warning introduced by: commit 67f1e027c270 ("drivers/cdrom: improved ioctl for media change detection") Suggested-by: Randy Dunlap Fixes: 67f1e027c270 ("drivers/cdrom: improved ioctl for media change detection") Signed-off-by: Phillip Potter Reviewed-by: Randy Dunlap Link: https://lore.kernel.org/r/20211007231720.31997-1-phil@philpotter.co.uk Signed-off-by: Jens Axboe

drivers/cdrom: improved ioctl for media change detection

2021-09-15T02:05:26Z

The current implementation of the CDROM_MEDIA_CHANGED ioctl relies on global state, meaning that only one process can detect a disc change while the ioctl call will return 0 for other calling processes afterwards (see bug 213267). This introduces a new cdrom ioctl, CDROM_TIMED_MEDIA_CHANGE, that works by maintaining a timestamp of the last detected disc change instead of a boolean flag: Processes calling this ioctl command can provide a timestamp of the last disc change known to them and receive an indication whether the disc was changed since then and the updated timestamp. I considered fixing the buggy behavior in the original CDROM_MEDIA_CHANGED ioctl but that would require maintaining state for each calling process in the kernel, which seems like a worse solution than introducing this new ioctl. Signed-off-by: Lukas Prediger Link: https://lore.kernel.org/all/20210912191207.74449-1-lumip@lumip.de Signed-off-by: Phillip Potter Link: https://lore.kernel.org/r/20210913230942.1188-1-phil@philpotter.co.uk Signed-off-by: Jens Axboe

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

2021-09-11T21:48:42Z

Pull virtio updates from Michael Tsirkin: - vduse driver ("vDPA Device in Userspace") supporting emulated virtio block devices - virtio-vsock support for end of record with SEQPACKET - vdpa: mac and mq support for ifcvf and mlx5 - vdpa: management netlink for ifcvf - virtio-i2c, gpio dt bindings - misc fixes and cleanups * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (39 commits) Documentation: Add documentation for VDUSE vduse: Introduce VDUSE - vDPA Device in Userspace vduse: Implement an MMU-based software IOTLB vdpa: Support transferring virtual addressing during DMA mapping vdpa: factor out vhost_vdpa_pa_map() and vhost_vdpa_pa_unmap() vdpa: Add an opaque pointer for vdpa_config_ops.dma_map() vhost-iotlb: Add an opaque pointer for vhost IOTLB vhost-vdpa: Handle the failure of vdpa_reset() vdpa: Add reset callback in vdpa_config_ops vdpa: Fix some coding style issues file: Export receive_fd() to modules eventfd: Export eventfd_wake_count to modules iova: Export alloc_iova_fast() and free_iova_fast() virtio-blk: remove unneeded "likely" statements virtio-balloon: Use virtio_find_vqs() helper vdpa: Make use of PFN_PHYS/PFN_UP/PFN_DOWN helper macro vsock_test: update message bounds test for MSG_EOR af_vsock: rename variables in receive loop virtio/vsock: support MSG_EOR bit processing vhost/vsock: support MSG_EOR bit processing ...

vduse: Introduce VDUSE - vDPA Device in Userspace

2021-09-06T11:20:58Z

This VDUSE driver enables implementing software-emulated vDPA devices in userspace. The vDPA device is created by ioctl(VDUSE_CREATE_DEV) on /dev/vduse/control. Then a char device interface (/dev/vduse/$NAME) is exported to userspace for device emulation. In order to make the device emulation more secure, the device's control path is handled in kernel. A message mechnism is introduced to forward some dataplane related control messages to userspace. And in the data path, the DMA buffer will be mapped into userspace address space through different ways depending on the vDPA bus to which the vDPA device is attached. In virtio-vdpa case, the MMU-based software IOTLB is used to achieve that. And in vhost-vdpa case, the DMA buffer is reside in a userspace memory region which can be shared to the VDUSE userspace processs via transferring the shmfd. For more details on VDUSE design and usage, please see the follow-on Documentation commit. NB(mst): when merging this with b542e383d8c0 ("eventfd: Make signal recursion protection a task bit") replace eventfd_signal_count with eventfd_signal_allowed, and drop the previous ("eventfd: Export eventfd_wake_count to modules"). Signed-off-by: Xie Yongji Acked-by: Jason Wang Link: https://lore.kernel.org/r/20210831103634.33-13-xieyongji@bytedance.com Signed-off-by: Michael S. Tsirkin