[PATCH 02/10] iommu: Add a lockdep assertion for remaining dev->iommu_group reads

[Baolu Lu]

On 2023/7/19 3:05, Jason Gunthorpe wrote:
> The remaining reads are all in functions called under ops->device_group.
> 
> Broadly these functions are walking around the device tree (eg going up
> the PCI bus tree) and are trying to de-duplicate group allocations
> according to their logic.
> 
> Since these functions don't hold any particular per-device locks their
> reads to dev->iommu_group are being locked by the caller's
> iommu_probe_device_lock, and this explains why iommu_probe_device_lock
> needs to be a global lock.
> 
> Rename iommu_probe_device_lock to dev_iommu_group_lock, make it local to
> the module and annotate all the device_group helpers with
> iommu_group_get_locked() that includes a lockdep to indicate that they are
> special.
> 
> Signed-off-by: Jason Gunthorpe<jgg at nvidia.com>

Reviewed-by: Lu Baolu <baolu.lu at linux.intel.com>

Best regards,
baolu