kernel/linux.git/include/linux/device/bus.h, branch v6.12.80

driver core: generalize driver_override in struct device

2026-04-02T11:09:25+00:00

[ Upstream commit cb3d1049f4ea77d5ad93f17d8ac1f2ed4da70501 ] Currently, there are 12 busses (including platform and PCI) that duplicate the driver_override logic for their individual devices. All of them seem to be prone to the bug described in [1]. While this could be solved for every bus individually using a separate lock, solving this in the driver-core generically results in less (and cleaner) changes overall. Thus, move driver_override to struct device, provide corresponding accessors for busses and handle locking with a separate lock internally. In particular, add device_set_driver_override(), device_has_driver_override(), device_match_driver_override() and generalize the sysfs store() and show() callbacks via a driver_override feature flag in struct bus_type. Until all busses have migrated, keep driver_set_override() in place. Note that we can't use the device lock for the reasons described in [2]. Link: https://bugzilla.kernel.org/show_bug.cgi?id=220789 [1] Link: https://lore.kernel.org/driver-core/DGRGTIRHA62X.3RY09D9SOK77P@kernel.org/ [2] Tested-by: Gui-Dong Han Co-developed-by: Gui-Dong Han Signed-off-by: Gui-Dong Han Reviewed-by: Greg Kroah-Hartman Link: https://patch.msgid.link/20260303115720.48783-2-dakr@kernel.org [ Use dev->bus instead of sp->bus for consistency; fix commit message to refer to the struct bus_type's driver_override feature flag. - Danilo ] Signed-off-by: Danilo Krummrich Stable-dep-of: 2b38efc05bf7 ("driver core: platform: use generic driver_override infrastructure") Signed-off-by: Sasha Levin

driver core: bus: add irq_get_affinity callback to bus_type

2025-04-25T08:47:38+00:00

[ Upstream commit fea4952df0eeec4e1a295ebaac9f61c0065fae87 ] Introducing a callback in struct bus_type so that a subsystem can hook up the getters directly. This approach avoids exposing random getters in any subsystems APIs. Acked-by: Bjorn Helgaas Reviewed-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Reviewed-by: Ming Lei Acked-by: Greg Kroah-Hartman Signed-off-by: Daniel Wagner Link: https://lore.kernel.org/r/20241202-refactor-blk-affinity-helpers-v6-1-27211e9c2cd5@kernel.org Signed-off-by: Jens Axboe Stable-dep-of: a2d5a0072235 ("scsi: smartpqi: Use is_kdump_kernel() to check for kdump") Signed-off-by: Sasha Levin

drivers/base: Introduce device_match_t for device finding APIs

2024-09-03T10:48:51+00:00

There are several drivers/base APIs for finding a specific device, and they currently use the following good type for the @match parameter: int (*match)(struct device *dev, const void *data) Since these operations do not modify the caller-provided @*data, this type is worthy of a dedicated typedef: typedef int (*device_match_t)(struct device *dev, const void *data) Advantages of using device_match_t: - Shorter API declarations and definitions - Prevent further APIs from using a bad type for @match So introduce device_match_t and apply it to the existing (bus|class|driver|auxiliary)_find_device() APIs. Signed-off-by: Zijun Hu Link: https://lore.kernel.org/r/20240813-dev_match_api-v3-1-6c6878a99b9f@quicinc.com Signed-off-by: Greg Kroah-Hartman

driver core: have match() callback in struct bus_type take a const *

2024-07-03T13:16:54+00:00

In the match() callback, the struct device_driver * should not be changed, so change the function callback to be a const *. This is one step of many towards making the driver core safe to have struct device_driver in read-only memory. Because the match() callback is in all busses, all busses are modified to handle this properly. This does entail switching some container_of() calls to container_of_const() to properly handle the constant *. For some busses, like PCI and USB and HV, the const * is cast away in the match callback as those busses do want to modify those structures at this point in time (they have a local lock in the driver structure.) That will have to be changed in the future if they wish to have their struct device * in read-only-memory. Cc: Rafael J. Wysocki Reviewed-by: Alex Elder Acked-by: Sumit Garg Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh Signed-off-by: Greg Kroah-Hartman

Merge tag 'iommu-updates-v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

2024-01-18T23:16:57+00:00

Pull iommu updates from Joerg Roedel: "Core changes: - Fix race conditions in device probe path - Retire IOMMU bus_ops - Support for passing custom allocators to page table drivers - Clean up Kconfig around IOMMU_SVA - Support for sharing SVA domains with all devices bound to a mm - Firmware data parsing cleanup - Tracing improvements for iommu-dma code - Some smaller fixes and cleanups ARM-SMMU drivers: - Device-tree binding updates: - Add additional compatible strings for Qualcomm SoCs - Document Adreno clocks for Qualcomm's SM8350 SoC - SMMUv2: - Implement support for the ->domain_alloc_paging() callback - Ensure Secure context is restored following suspend of Qualcomm SMMU implementation - SMMUv3: - Disable stalling mode for the "quiet" context descriptor - Minor refactoring and driver cleanups Intel VT-d driver: - Cleanup and refactoring AMD IOMMU driver: - Improve IO TLB invalidation logic - Small cleanups and improvements Rockchip IOMMU driver: - DT binding update to add Rockchip RK3588 Apple DART driver: - Apple M1 USB4/Thunderbolt DART support - Cleanups Virtio IOMMU driver: - Add support for iotlb_sync_map - Enable deferred IO TLB flushes" * tag 'iommu-updates-v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (66 commits) iommu: Don't reserve 0-length IOVA region iommu/vt-d: Move inline helpers to header files iommu/vt-d: Remove unused vcmd interfaces iommu/vt-d: Remove unused parameter of intel_pasid_setup_pass_through() iommu/vt-d: Refactor device_to_iommu() to retrieve iommu directly iommu/sva: Fix memory leak in iommu_sva_bind_device() dt-bindings: iommu: rockchip: Add Rockchip RK3588 iommu/dma: Trace bounce buffer usage when mapping buffers iommu/arm-smmu: Convert to domain_alloc_paging() iommu/arm-smmu: Pass arm_smmu_domain to internal functions iommu/arm-smmu: Implement IOMMU_DOMAIN_BLOCKED iommu/arm-smmu: Convert to a global static identity domain iommu/arm-smmu: Reorganize arm_smmu_domain_add_master() iommu/arm-smmu-v3: Remove ARM_SMMU_DOMAIN_NESTED iommu/arm-smmu-v3: Master cannot be NULL in arm_smmu_write_strtab_ent() iommu/arm-smmu-v3: Add a type for the STE iommu/arm-smmu-v3: disable stall for quiet_cd iommu/qcom: restore IOMMU state if needed iommu/arm-smmu-qcom: Add QCM2290 MDSS compatible iommu/arm-smmu-qcom: Add missing GMU entry to match table ...

driver core: bus: make bus_sort_breadthfirst() take a const pointer

2023-12-21T12:55:08+00:00

For some reason, during the big "clean up the driver core for a const struct bus_type" work, the bus_sort_breadthfirst() call was missed. Fix this up by changing the type to be a const * as it should be. Cc: Rafael J. Wysocki Link: https://lore.kernel.org/r/2023121935-stinking-ditzy-fd5d@gregkh Signed-off-by: Greg Kroah-Hartman

iommu: Retire bus ops

2023-11-27T10:03:15+00:00

With the rest of the API internals converted, it's time to finally tackle probe_device and how we bootstrap the per-device ops association to begin with. This ends up being disappointingly straightforward, since fwspec users are already doing it in order to find their of_xlate callback, and it works out that we can easily do the equivalent for other drivers too. Then shuffle the remaining awareness of iommu_ops into the couple of core headers that still need it, and breathe a sigh of relief. Ding dong the bus ops are gone! CC: Rafael J. Wysocki Acked-by: Christoph Hellwig Acked-by: Greg Kroah-Hartman Reviewed-by: Lu Baolu Reviewed-by: Jason Gunthorpe Reviewed-by: Jerry Snitselaar Signed-off-by: Robin Murphy Link: https://lore.kernel.org/r/a59011ef65b4b6657cb0b7a388d786b779b61305.1700589539.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel

driver core: bus: move documentation for lock_key to proper location.

2023-03-25T08:38:08+00:00

In commit 37e98d9bedb5 ("driver core: bus: move lock_class_key into dynamic structure"), the lock_key variable moved out of struct bus_type and into struct subsys_private, yet the documentation for it did not move. Fix that up and place the documentation comment in the correct location. Cc: "Rafael J. Wysocki" Fixes: 37e98d9bedb5 ("driver core: bus: move lock_class_key into dynamic structure") Link: https://lore.kernel.org/r/20230324090814.386654-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

driver core: bus.h: remove extern from function prototypes

2023-03-24T14:35:38+00:00

The kernel coding style does not require 'extern' in function prototypes in .h files, so remove them from include/linux/device/bus.h as they are not needed. Acked-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20230324122711.2664537-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

driver core: bus: constify bus_rescan_devices()

2023-03-23T12:21:20+00:00

The bus_rescan_devices() function was missed in the previous change of the bus_for_each* constant pointer changes, so fix it up now to take a const * to struct bus_type. Cc: "Rafael J. Wysocki" Link: https://lore.kernel.org/r/20230313182918.1312597-25-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman