user/sven/linux.git/include/linux/hmm.h, branch v5.4.38

hmm: use mmu_notifier_get/put for 'struct hmm'

2019-08-20T12:35:02Z

This is a significant simplification, it eliminates all the remaining 'hmm' stuff in mm_struct, eliminates krefing along the critical notifier paths, and takes away all the ugly locking and abuse of page_table_lock. mmu_notifier_get() provides the single struct hmm per struct mm which eliminates mm->hmm. It also directly guarantees that no mmu_notifier op callback is callable while concurrent free is possible, this eliminates all the krefs inside the mmu_notifier callbacks. The remaining krefs in the range code were overly cautious, drivers are already not permitted to free the mirror while a range exists. Link: https://lore.kernel.org/r/20190806231548.25242-6-jgg@ziepe.ca Reviewed-by: Christoph Hellwig Reviewed-by: Ralph Campbell Tested-by: Ralph Campbell Signed-off-by: Jason Gunthorpe

mm/hmm: remove the page_shift member from struct hmm_range

2019-08-07T17:58:06Z

All users pass PAGE_SIZE here, and if we wanted to support single entries for huge pages we should really just add a HMM_FAULT_HUGEPAGE flag instead that uses the huge page size instead of having the caller calculate that size once, just for the hmm code to verify it. Link: https://lore.kernel.org/r/20190806160554.14046-8-hch@lst.de Signed-off-by: Christoph Hellwig Acked-by: Felix Kuehling Reviewed-by: Jason Gunthorpe Signed-off-by: Jason Gunthorpe

mm/hmm: remove superfluous arguments from hmm_range_register

2019-08-07T17:58:05Z

The start, end and page_shift values are all saved in the range structure, so we might as well use that for argument passing. Link: https://lore.kernel.org/r/20190806160554.14046-7-hch@lst.de Signed-off-by: Christoph Hellwig Reviewed-by: Jason Gunthorpe Reviewed-by: Felix Kuehling Signed-off-by: Jason Gunthorpe

mm/hmm: remove the unused vma argument to hmm_range_dma_unmap

2019-08-07T17:58:05Z

Link: https://lore.kernel.org/r/20190806160554.14046-6-hch@lst.de Signed-off-by: Christoph Hellwig Reviewed-by: Jason Gunthorpe Signed-off-by: Jason Gunthorpe

mm/hmm: remove hmm_range vma

2019-07-26T15:35:29Z

Since hmm_range_fault() doesn't use the struct hmm_range vma field, remove it. Link: https://lore.kernel.org/r/20190726005650.2566-8-rcampbell@nvidia.com Suggested-by: Jason Gunthorpe Signed-off-by: Ralph Campbell Reviewed-by: Christoph Hellwig Reviewed-by: Jason Gunthorpe Signed-off-by: Jason Gunthorpe

mm/hmm: merge hmm_range_snapshot into hmm_range_fault

2019-07-26T14:10:53Z

Add a HMM_FAULT_SNAPSHOT flag so that hmm_range_snapshot can be merged into the almost identical hmm_range_fault function. Link: https://lore.kernel.org/r/20190726005650.2566-5-rcampbell@nvidia.com Signed-off-by: Christoph Hellwig Signed-off-by: Ralph Campbell Reviewed-by: Jason Gunthorpe Signed-off-by: Jason Gunthorpe

mm/hmm: replace the block argument to hmm_range_fault with a flags value

2019-07-26T14:10:53Z

This allows easier expansion to other flags, and also makes the callers a little easier to read. Link: https://lore.kernel.org/r/20190726005650.2566-4-rcampbell@nvidia.com Signed-off-by: Christoph Hellwig Signed-off-by: Ralph Campbell Reviewed-by: Jason Gunthorpe Signed-off-by: Jason Gunthorpe

mm/hmm: replace hmm_update with mmu_notifier_range

2019-07-26T14:10:53Z

The hmm_mirror_ops callback function sync_cpu_device_pagetables() passes a struct hmm_update which is a simplified version of struct mmu_notifier_range. This is unnecessary so replace hmm_update with mmu_notifier_range directly. Link: https://lore.kernel.org/r/20190726005650.2566-2-rcampbell@nvidia.com Signed-off-by: Ralph Campbell Reviewed: Christoph Hellwig Reviewed-by: Jason Gunthorpe [jgg: white space tuning] Signed-off-by: Jason Gunthorpe

mm/hmm: remove the legacy hmm_pfn_* APIs

2019-07-25T19:14:40Z

Switch the one remaining user in nouveau over to its replacement, and remove all the wrappers. Link: https://lore.kernel.org/r/20190724065258.16603-7-hch@lst.de Tested-by: Ralph Campbell Signed-off-by: Christoph Hellwig Reviewed-by: Ralph Campbell Reviewed-by: Jason Gunthorpe Signed-off-by: Jason Gunthorpe

mm/hmm: move hmm_vma_range_done and hmm_vma_fault to nouveau

2019-07-25T19:14:39Z

These two functions are marked as a legacy APIs to get rid of, but seem to suit the current nouveau flow. Move it to the only user in preparation for fixing a locking bug involving caller and callee. All comments referring to the old API have been removed as this now is a driver private helper. Link: https://lore.kernel.org/r/20190724065258.16603-3-hch@lst.de Tested-by: Ralph Campbell Signed-off-by: Christoph Hellwig Reviewed-by: Jason Gunthorpe Signed-off-by: Jason Gunthorpe