Now that the domain allocation path is less duplicated we can tackle the probe_device path. Details of this are spread across several functions, broadly move most of the code into __iommu_probe_device() and organize it more strictly in terms of paired do/undo functions. Make the locking simpler by obtaining the group->mutex fewer times and avoiding adding a half-initialized device to an initialized group. Previously we would lock/unlock the group three times on these paths. This locking change is the primary point of the series, creating the paired do/undo functions is a path to being able to organize the setup code under a single lock and still have a logical, not duplicated, error unwind. The reorganizing is done with the idea that a following series will consolidate all of the different places calling arm_iommu_create_mapping() and iommu_setup_dma_ops() into the new consolidated probe path and get rid of probe_finalize. This follows the prior series: https://lore.kernel.org/r/0-v5-1b99ae392328+44574-iommu_err_unwind_jgg@xxxxxxxxxx And while it doesn't really depend on, some of the explanations around the add/remove group logic assume these two: https://lore.kernel.org/r/0-v1-1421774b874b+167-ppc_device_group_jgg@xxxxxxxxxx https://lore.kernel.org/r/0-v2-ce71068deeec+4cf6-fsl_rm_groups_jgg@xxxxxxxxxx This is on github: https://github.com/jgunthorpe/linux/commits/iommu_probe v2: - Rebase to v6.4-rc2 - Move the POWER cleanup to an independent -rc fix due to the iommu driver being merged - Update commit messages - Rename iommu_init_driver() to iommu_init_device() - Simplify __iommu_group_remove_device() v1: https://lore.kernel.org/r/0-v1-8aecc628b904+2f42-iommu_probe_jgg@xxxxxxxxxx Jason Gunthorpe (10): iommu: Have __iommu_probe_device() check for already probed devices iommu: Use iommu_group_ref_get/put() for dev->iommu_group iommu: Inline iommu_group_get_for_dev() into __iommu_probe_device() iommu: Simplify the __iommu_group_remove_device() flow iommu: Add iommu_init/deinit_device() paired functions iommu: Move the iommu driver sysfs setup into iommu_init/deinit_device() iommu: Do not export iommu_device_link/unlink() iommu: Always destroy the iommu_group during iommu_release_device() iommu: Split iommu_group_add_device() iommu: Avoid locking/unlocking for iommu_probe_device() drivers/acpi/scan.c | 2 +- drivers/iommu/intel/iommu.c | 7 - drivers/iommu/iommu-sysfs.c | 8 - drivers/iommu/iommu.c | 462 ++++++++++++++++++------------------ drivers/iommu/of_iommu.c | 2 +- 5 files changed, 239 insertions(+), 242 deletions(-) base-commit: 8f6c3fcaa76a9222f435230972b4f0f5c3672cad -- 2.40.1
