kernel/drivers/char/mem.c, branch linux-6.9.y

Merge tag 'char-misc-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2023-11-04T00:51:08Z

Pull char/misc updates from Greg KH: "Here is the big set of char/misc and other small driver subsystem changes for 6.7-rc1. Included in here are: - IIO subsystem driver updates and additions (largest part of this pull request) - FPGA subsystem driver updates - Counter subsystem driver updates - ICC subsystem driver updates - extcon subsystem driver updates - mei driver updates and additions - nvmem subsystem driver updates and additions - comedi subsystem dependency fixes - parport driver fixups - cdx subsystem driver and core updates - splice support for /dev/zero and /dev/full - other smaller driver cleanups All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (326 commits) cdx: add sysfs for subsystem, class and revision cdx: add sysfs for bus reset cdx: add support for bus enable and disable cdx: Register cdx bus as a device on cdx subsystem cdx: Create symbol namespaces for cdx subsystem cdx: Introduce lock to protect controller ops cdx: Remove cdx controller list from cdx bus system dts: ti: k3-am625-beagleplay: Add beaglecc1352 greybus: Add BeaglePlay Linux Driver dt-bindings: net: Add ti,cc1352p7 dt-bindings: eeprom: at24: allow NVMEM cells based on old syntax dt-bindings: nvmem: SID: allow NVMEM cells based on old syntax Revert "nvmem: add new config option" MAINTAINERS: coresight: Add missing Coresight files misc: pci_endpoint_test: Add deviceID for J721S2 PCIe EP device support firmware: xilinx: Move EXPORT_SYMBOL_GPL next to zynqmp_pm_feature definition uacce: make uacce_class constant ocxl: make ocxl_class constant cxl: make cxl_class constant misc: phantom: make phantom_class constant ...

drivers/char/mem: implement splice() for /dev/zero, /dev/full

2023-10-05T11:34:05Z

This allows splicing zeroed pages into a pipe, and allows discarding pages from a pipe by splicing them to /dev/zero. Writing to /dev/zero should have the same effect as writing to /dev/null, and a "splice_write" implementation exists only for /dev/null. (The /dev/zero splice_read implementation could be optimized by pushing references to the global zero page to the pipe, but that's an optimization for another day.) Signed-off-by: Max Kellermann Link: https://lore.kernel.org/r/20230919073743.1066313-1-max.kellermann@ionos.com Signed-off-by: Greg Kroah-Hartman

arch: Remove Itanium (IA-64) architecture

2023-09-11T08:13:17Z

The Itanium architecture is obsolete, and an informal survey [0] reveals that any residual use of Itanium hardware in production is mostly HP-UX or OpenVMS based. The use of Linux on Itanium appears to be limited to enthusiasts that occasionally boot a fresh Linux kernel to see whether things are still working as intended, and perhaps to churn out some distro packages that are rarely used in practice. None of the original companies behind Itanium still produce or support any hardware or software for the architecture, and it is listed as 'Orphaned' in the MAINTAINERS file, as apparently, none of the engineers that contributed on behalf of those companies (nor anyone else, for that matter) have been willing to support or maintain the architecture upstream or even be responsible for applying the odd fix. The Intel firmware team removed all IA-64 support from the Tianocore/EDK2 reference implementation of EFI in 2018. (Itanium is the original architecture for which EFI was developed, and the way Linux supports it deviates significantly from other architectures.) Some distros, such as Debian and Gentoo, still maintain [unofficial] ia64 ports, but many have dropped support years ago. While the argument is being made [1] that there is a 'for the common good' angle to being able to build and run existing projects such as the Grid Community Toolkit [2] on Itanium for interoperability testing, the fact remains that none of those projects are known to be deployed on Linux/ia64, and very few people actually have access to such a system in the first place. Even if there were ways imaginable in which Linux/ia64 could be put to good use today, what matters is whether anyone is actually doing that, and this does not appear to be the case. There are no emulators widely available, and so boot testing Itanium is generally infeasible for ordinary contributors. GCC still supports IA-64 but its compile farm [3] no longer has any IA-64 machines. GLIBC would like to get rid of IA-64 [4] too because it would permit some overdue code cleanups. In summary, the benefits to the ecosystem of having IA-64 be part of it are mostly theoretical, whereas the maintenance overhead of keeping it supported is real. So let's rip off the band aid, and remove the IA-64 arch code entirely. This follows the timeline proposed by the Debian/ia64 maintainer [5], which removes support in a controlled manner, leaving IA-64 in a known good state in the most recent LTS release. Other projects will follow once the kernel support is removed. [0] https://lore.kernel.org/all/CAMj1kXFCMh_578jniKpUtx_j8ByHnt=s7S+yQ+vGbKt9ud7+kQ@mail.gmail.com/ [1] https://lore.kernel.org/all/0075883c-7c51-00f5-2c2d-5119c1820410@web.de/ [2] https://gridcf.org/gct-docs/latest/index.html [3] https://cfarm.tetaneutral.net/machines/list/ [4] https://lore.kernel.org/all/87bkiilpc4.fsf@mid.deneb.enyo.de/ [5] https://lore.kernel.org/all/ff58a3e76e5102c94bb5946d99187b358def688a.camel@physik.fu-berlin.de/ Acked-by: Tony Luck Signed-off-by: Ard Biesheuvel

drivers/char/mem.c: shrink character device's devlist[] array

2023-08-24T23:25:15Z

Merge padding, shrinking "struct memdev" from 32 bytes to 24 bytes on 64-bit. Link: https://lkml.kernel.org/r/fe4d62ab-2427-4635-b9f4-467853fb63e3@p183 Signed-off-by: Alexey Dobriyan Cc: Greg Kroah-Hartman Signed-off-by: Andrew Morton

Merge tag 'char-misc-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2023-07-03T19:46:47Z

Pull Char/Misc updates from Greg KH: "Here is the big set of char/misc and other driver subsystem updates for 6.5-rc1. Lots of different, tiny, stuff in here, from a range of smaller driver subsystems, including pulls from some substems directly: - IIO driver updates and additions - W1 driver updates and fixes (and a new maintainer!) - FPGA driver updates and fixes - Counter driver updates - Extcon driver updates - Interconnect driver updates - Coresight driver updates - mfd tree tag merge needed for other updates on top of that, lots of small driver updates as patches, including: - static const updates for class structures - nvmem driver updates - pcmcia driver fix - lots of other small driver updates and fixes All of these have been in linux-next for a while with no reported problems" * tag 'char-misc-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (243 commits) bsr: fix build problem with bsr_class static cleanup comedi: make all 'class' structures const char: xillybus: make xillybus_class a static const structure xilinx_hwicap: make icap_class a static const structure virtio_console: make port class a static const structure ppdev: make ppdev_class a static const structure char: misc: make misc_class a static const structure /dev/mem: make mem_class a static const structure char: lp: make lp_class a static const structure dsp56k: make dsp56k_class a static const structure bsr: make bsr_class a static const structure oradax: make 'cl' a static const structure hwtracing: hisi_ptt: Fix potential sleep in atomic context hwtracing: hisi_ptt: Advertise PERF_PMU_CAP_NO_EXCLUDE for PTT PMU hwtracing: hisi_ptt: Export available filters through sysfs hwtracing: hisi_ptt: Add support for dynamically updating the filter list hwtracing: hisi_ptt: Factor out filter allocation and release operation samples: pfsm: add CC_CAN_LINK dependency misc: fastrpc: check return value of devm_kasprintf() coresight: dummy: Update type of mode parameter in dummy_{sink,source}_enable() ...

/dev/mem: make mem_class a static const structure

2023-06-23T08:27:13Z

Now that the driver core allows for struct class to be in read-only memory, move the mem_class structure to be declared at build time placing it into read-only memory, instead of having to be dynamically allocated at load time. Cc: Arnd Bergmann Suggested-by: Greg Kroah-Hartman Signed-off-by: Ivan Orlov Link: https://lore.kernel.org/r/20230620143751.578239-13-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

mips: provide unxlate_dev_mem_ptr() in asm/io.h

2023-06-09T07:48:53Z

The unxlate_dev_mem_ptr() function has no prototype on the mips architecture, which does not include asm-generic/io.h, so gcc warns about the __weak definition: drivers/char/mem.c:94:29: error: no previous prototype for 'unxlate_dev_mem_ptr' [-Werror=missing-prototypes] Since everyone else already gets the generic definition or has a custom one, there is not really much point in having a __weak version as well. Remove this one, and instead add a trivial macro to the mips header. Once we convert mips to use the asm-generic header, this can go away again. Signed-off-by: Arnd Bergmann Signed-off-by: Thomas Bogendoerfer

driver core: class: remove module * from class_create()

2023-03-17T14:16:33Z

The module pointer in class_create() never actually did anything, and it shouldn't have been requred to be set as a parameter even if it did something. So just remove it and fix up all callers of the function in the kernel tree at the same time. Cc: "Rafael J. Wysocki" Acked-by: Benjamin Tissoires Link: https://lore.kernel.org/r/20230313181843.1207845-4-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

mm/nommu: factor out check for NOMMU shared mappings into is_nommu_shared_mapping()

2023-01-19T01:12:56Z

Patch series "mm/nommu: don't use VM_MAYSHARE for MAP_PRIVATE mappings". Trying to reduce the confusion around VM_SHARED and VM_MAYSHARE first requires !CONFIG_MMU to stop using VM_MAYSHARE for MAP_PRIVATE mappings. CONFIG_MMU only sets VM_MAYSHARE for MAP_SHARED mappings. This paves the way for further VM_MAYSHARE and VM_SHARED cleanups: for example, renaming VM_MAYSHARED to VM_MAP_SHARED to make it cleaner what is actually means. Let's first get the weird case out of the way and not use VM_MAYSHARE in MAP_PRIVATE mappings, using a new VM_MAYOVERLAY flag instead. This patch (of 3): We want to stop using VM_MAYSHARE in private mappings to pave the way for clarifying the semantics of VM_MAYSHARE vs. VM_SHARED and reduce the confusion. While CONFIG_MMU uses VM_MAYSHARE to represent MAP_SHARED, !CONFIG_MMU also sets VM_MAYSHARE for selected R/O private file mappings that are an effective overlay of a file mapping. Let's factor out all relevant VM_MAYSHARE checks in !CONFIG_MMU code into is_nommu_shared_mapping() first. Note that whenever VM_SHARED is set, VM_MAYSHARE must be set as well (unless there is a serious BUG). So there is not need to test for VM_SHARED manually. No functional change intended. Link: https://lkml.kernel.org/r/20230102160856.500584-1-david@redhat.com Link: https://lkml.kernel.org/r/20230102160856.500584-2-david@redhat.com Signed-off-by: David Hildenbrand Cc: Arnd Bergmann Cc: David Hildenbrand Cc: Greg Kroah-Hartman Cc: Jens Axboe Cc: Nicolas Pitre Cc: Pavel Begunkov Signed-off-by: Andrew Morton

driver core: make struct class.devnode() take a const *

2022-11-24T16:12:27Z

The devnode() in struct class should not be modifying the device that is passed into it, so mark it as a const * and propagate the function signature changes out into all relevant subsystems that use this callback. Cc: Fenghua Yu Cc: Reinette Chatre Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Cc: x86@kernel.org Cc: "H. Peter Anvin" Cc: FUJITA Tomonori Cc: Jens Axboe Cc: Justin Sanders Cc: Arnd Bergmann Cc: Sumit Semwal Cc: Benjamin Gaignard Cc: Liam Mark Cc: Laura Abbott Cc: Brian Starkey Cc: John Stultz Cc: "Christian König" Cc: Maarten Lankhorst Cc: Maxime Ripard Cc: Thomas Zimmermann Cc: David Airlie Cc: Daniel Vetter Cc: Jason Gunthorpe Cc: Leon Romanovsky Cc: Dennis Dalessandro Cc: Dmitry Torokhov Cc: Mauro Carvalho Chehab Cc: Sean Young Cc: Frank Haverkamp Cc: Jiri Slaby Cc: "Michael S. Tsirkin" Cc: Jason Wang Cc: Alex Williamson Cc: Cornelia Huck Cc: Kees Cook Cc: Anton Vorontsov Cc: Colin Cross Cc: Tony Luck Cc: Jaroslav Kysela Cc: Takashi Iwai Cc: Hans Verkuil Cc: Christophe JAILLET Cc: Xie Yongji Cc: Gautam Dawar Cc: Dan Carpenter Cc: Eli Cohen Cc: Parav Pandit Cc: Maxime Coquelin Cc: alsa-devel@alsa-project.org Cc: dri-devel@lists.freedesktop.org Cc: kvm@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org Cc: linux-block@vger.kernel.org Cc: linux-input@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: linux-rdma@vger.kernel.org Cc: linux-scsi@vger.kernel.org Cc: linux-usb@vger.kernel.org Cc: virtualization@lists.linux-foundation.org Link: https://lore.kernel.org/r/20221123122523.1332370-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman