kernel/linux.git/drivers/char/mem.c, branch v6.12.80

fs: move FMODE_UNSIGNED_OFFSET to fop_flags

2024-08-30T06:22:36+00:00

This is another flag that is statically set and doesn't need to use up an FMODE_* bit. Move it to ->fop_flags and free up another FMODE_* bit. (1) mem_open() used from proc_mem_operations (2) adi_open() used from adi_fops (3) drm_open_helper(): (3.1) accel_open() used from DRM_ACCEL_FOPS (3.2) drm_open() used from (3.2.1) amdgpu_driver_kms_fops (3.2.2) psb_gem_fops (3.2.3) i915_driver_fops (3.2.4) nouveau_driver_fops (3.2.5) panthor_drm_driver_fops (3.2.6) radeon_driver_kms_fops (3.2.7) tegra_drm_fops (3.2.8) vmwgfx_driver_fops (3.2.9) xe_driver_fops (3.2.10) DRM_GEM_FOPS (3.2.11) DEFINE_DRM_GEM_DMA_FOPS (4) struct memdev sets fmode flags based on type of device opened. For devices using struct mem_fops unsigned offset is used. Mark all these file operations as FOP_UNSIGNED_OFFSET and add asserts into the open helper to ensure that the flag is always set. Link: https://lore.kernel.org/r/20240809-work-fop_unsigned-v1-1-658e054d893e@kernel.org Reviewed-by: Jeff Layton Reviewed-by: Jan Kara Signed-off-by: Christian Brauner

Merge tag 'char-misc-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2024-05-22T19:26:46+00:00

Pull char/misc and other driver subsystem updates from Greg KH: "Here is the big set of char/misc and other driver subsystem updates for 6.10-rc1. Nothing major here, just lots of new drivers and updates for apis and new hardware types. Included in here are: - big IIO driver updates with more devices and drivers added - fpga driver updates - hyper-v driver updates - uio_pruss driver removal, no one uses it, other drivers control the same hardware now - binder minor updates - mhi driver updates - excon driver updates - counter driver updates - accessability driver updates - coresight driver updates - other hwtracing driver updates - nvmem driver updates - slimbus driver updates - spmi driver updates - other smaller misc and char driver updates All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (319 commits) misc: ntsync: mark driver as "broken" to prevent from building spmi: pmic-arb: Add multi bus support spmi: pmic-arb: Register controller for bus instead of arbiter spmi: pmic-arb: Make core resources acquiring a version operation spmi: pmic-arb: Make the APID init a version operation spmi: pmic-arb: Fix some compile warnings about members not being described dt-bindings: spmi: Deprecate qcom,bus-id dt-bindings: spmi: Add X1E80100 SPMI PMIC ARB schema spmi: pmic-arb: Replace three IS_ERR() calls by null pointer checks in spmi_pmic_arb_probe() spmi: hisi-spmi-controller: Do not override device identifier dt-bindings: spmi: hisilicon,hisi-spmi-controller: clean up example dt-bindings: spmi: hisilicon,hisi-spmi-controller: fix binding references spmi: make spmi_bus_type const extcon: adc-jack: Document missing struct members extcon: realtek: Remove unused of_gpio.h extcon: usbc-cros-ec: Convert to platform remove callback returning void extcon: usb-gpio: Convert to platform remove callback returning void extcon: max77843: Convert to platform remove callback returning void extcon: max3355: Convert to platform remove callback returning void extcon: intel-mrfld: Convert to platform remove callback returning void ...

mm: switch mm->get_unmapped_area() to a flag

2024-04-26T03:56:25+00:00

The mm_struct contains a function pointer *get_unmapped_area(), which is set to either arch_get_unmapped_area() or arch_get_unmapped_area_topdown() during the initialization of the mm. Since the function pointer only ever points to two functions that are named the same across all arch's, a function pointer is not really required. In addition future changes will want to add versions of the functions that take additional arguments. So to save a pointers worth of bytes in mm_struct, and prevent adding additional function pointers to mm_struct in future changes, remove it and keep the information about which get_unmapped_area() to use in a flag. Add the new flag to MMF_INIT_MASK so it doesn't get clobbered on fork by mmf_init_flags(). Most MM flags get clobbered on fork. In the pre-existing behavior mm->get_unmapped_area() would get copied to the new mm in dup_mm(), so not clobbering the flag preserves the existing behavior around inheriting the topdown-ness. Introduce a helper, mm_get_unmapped_area(), to easily convert code that refers to the old function pointer to instead select and call either arch_get_unmapped_area() or arch_get_unmapped_area_topdown() based on the flag. Then drop the mm->get_unmapped_area() function pointer. Leave the get_unmapped_area() pointer in struct file_operations alone. The main purpose of this change is to reorganize in preparation for future changes, but it also converts the calls of mm->get_unmapped_area() from indirect branches into a direct ones. The stress-ng bigheap benchmark calls realloc a lot, which calls through get_unmapped_area() in the kernel. On x86, the change yielded a ~1% improvement there on a retpoline config. In testing a few x86 configs, removing the pointer unfortunately didn't result in any actual size reductions in the compiled layout of mm_struct. But depending on compiler or arch alignment requirements, the change could shrink the size of mm_struct. Link: https://lkml.kernel.org/r/20240326021656.202649-3-rick.p.edgecombe@intel.com Signed-off-by: Rick Edgecombe Acked-by: Dave Hansen Acked-by: Liam R. Howlett Reviewed-by: Kirill A. Shutemov Acked-by: Alexei Starovoitov Cc: Dan Williams Cc: Andy Lutomirski Cc: Aneesh Kumar K.V Cc: Borislav Petkov (AMD) Cc: Christophe Leroy Cc: Deepak Gupta Cc: Guo Ren Cc: Helge Deller Cc: H. Peter Anvin (Intel) Cc: Ingo Molnar Cc: "James E.J. Bottomley" Cc: Kees Cook Cc: Mark Brown Cc: Michael Ellerman Cc: Naveen N. Rao Cc: Nicholas Piggin Cc: Peter Zijlstra Cc: Thomas Gleixner Signed-off-by: Andrew Morton

/dev/port: don't compile file operations without CONFIG_DEVPORT

2024-04-11T13:26:55+00:00

In the future inb() and friends will not be available when compiling with CONFIG_HAS_IOPORT=n so we must only try to access them here if CONFIG_DEVPORT is set which depends on HAS_IOPORT. Co-developed-by: Arnd Bergmann Signed-off-by: Arnd Bergmann Signed-off-by: Niklas Schnelle Link: https://lore.kernel.org/r/20240404114917.3627747-2-schnelle@linux.ibm.com Signed-off-by: Greg Kroah-Hartman

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

2023-11-04T00:51:08+00:00

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

2023-10-05T11:34:05+00:00

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

2023-09-11T08:13:17+00:00

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

2023-08-24T23:25:15+00:00

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

2023-07-03T19:46:47+00:00

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

2023-06-23T08:27:13+00:00

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