On 2019-07-30 1:51 a.m., Christoph Hellwig wrote:
> The start, end and page_shift values are all saved in the range
> structure, so we might as well use that for argument passing.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Felix Kuehling <Felix.Kuehling@xxxxxxx>
> ---
> Documentation/vm/hmm.rst | 2 +-
> drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 7 +++++--
> drivers/gpu/drm/nouveau/nouveau_svm.c | 5 ++---
> include/linux/hmm.h | 6 +-----
> mm/hmm.c | 20 +++++---------------
> 5 files changed, 14 insertions(+), 26 deletions(-)
>
> diff --git a/Documentation/vm/hmm.rst b/Documentation/vm/hmm.rst
> index ddcb5ca8b296..e63c11f7e0e0 100644
> --- a/Documentation/vm/hmm.rst
> +++ b/Documentation/vm/hmm.rst
> @@ -222,7 +222,7 @@ The usage pattern is::
> range.flags = ...;
> range.values = ...;
> range.pfn_shift = ...;
> - hmm_range_register(&range);
> + hmm_range_register(&range, mirror);
>
> /*
> * Just wait for range to be valid, safe to ignore return value as we
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> index f0821638bbc6..71d6e7087b0b 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> @@ -818,8 +818,11 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages)
> 0 : range->flags[HMM_PFN_WRITE];
> range->pfn_flags_mask = 0;
> range->pfns = pfns;
> - hmm_range_register(range, mirror, start,
> - start + ttm->num_pages * PAGE_SIZE, PAGE_SHIFT);
> + range->page_shift = PAGE_SHIFT;
> + range->start = start;
> + range->end = start + ttm->num_pages * PAGE_SIZE;
> +
> + hmm_range_register(range, mirror);
>
> /*
> * Just wait for range to be valid, safe to ignore return value as we
> diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.c b/drivers/gpu/drm/nouveau/nouveau_svm.c
> index b889d5ec4c7e..40e706234554 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_svm.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_svm.c
> @@ -492,9 +492,7 @@ nouveau_range_fault(struct nouveau_svmm *svmm, struct hmm_range *range)
> range->default_flags = 0;
> range->pfn_flags_mask = -1UL;
>
> - ret = hmm_range_register(range, &svmm->mirror,
> - range->start, range->end,
> - PAGE_SHIFT);
> + ret = hmm_range_register(range, &svmm->mirror);
> if (ret) {
> up_read(&range->hmm->mm->mmap_sem);
> return (int)ret;
> @@ -682,6 +680,7 @@ nouveau_svm_fault(struct nvif_notify *notify)
> args.i.p.addr + args.i.p.size, fn - fi);
>
> /* Have HMM fault pages within the fault window to the GPU. */
> + range.page_shift = PAGE_SHIFT;
> range.start = args.i.p.addr;
> range.end = args.i.p.addr + args.i.p.size;
> range.pfns = args.phys;
> diff --git a/include/linux/hmm.h b/include/linux/hmm.h
> index 59be0aa2476d..c5b51376b453 100644
> --- a/include/linux/hmm.h
> +++ b/include/linux/hmm.h
> @@ -400,11 +400,7 @@ void hmm_mirror_unregister(struct hmm_mirror *mirror);
> /*
> * Please see Documentation/vm/hmm.rst for how to use the range API.
> */
> -int hmm_range_register(struct hmm_range *range,
> - struct hmm_mirror *mirror,
> - unsigned long start,
> - unsigned long end,
> - unsigned page_shift);
> +int hmm_range_register(struct hmm_range *range, struct hmm_mirror *mirror);
> void hmm_range_unregister(struct hmm_range *range);
>
> /*
> diff --git a/mm/hmm.c b/mm/hmm.c
> index 3a3852660757..926735a3aef9 100644
> --- a/mm/hmm.c
> +++ b/mm/hmm.c
> @@ -843,35 +843,25 @@ static void hmm_pfns_clear(struct hmm_range *range,
> * hmm_range_register() - start tracking change to CPU page table over a range
> * @range: range
> * @mm: the mm struct for the range of virtual address
> - * @start: start virtual address (inclusive)
> - * @end: end virtual address (exclusive)
> - * @page_shift: expect page shift for the range
> + *
> * Return: 0 on success, -EFAULT if the address space is no longer valid
> *
> * Track updates to the CPU page table see include/linux/hmm.h
> */
> -int hmm_range_register(struct hmm_range *range,
> - struct hmm_mirror *mirror,
> - unsigned long start,
> - unsigned long end,
> - unsigned page_shift)
> +int hmm_range_register(struct hmm_range *range, struct hmm_mirror *mirror)
> {
> - unsigned long mask = ((1UL << page_shift) - 1UL);
> + unsigned long mask = ((1UL << range->page_shift) - 1UL);
> struct hmm *hmm = mirror->hmm;
> unsigned long flags;
>
> range->valid = false;
> range->hmm = NULL;
>
> - if ((start & mask) || (end & mask))
> + if ((range->start & mask) || (range->end & mask))
> return -EINVAL;
> - if (start >= end)
> + if (range->start >= range->end)
> return -EINVAL;
>
> - range->page_shift = page_shift;
> - range->start = start;
> - range->end = end;
> -
> /* Prevent hmm_release() from running while the range is valid */
> if (!mmget_not_zero(hmm->mm))
> return -EFAULT;
