Commit 7f08263d authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jason Gunthorpe
Browse files

mm/hmm: remove the page_shift member from struct hmm_range 

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: default avatarChristoph Hellwig <hch@lst.de>
Acked-by: default avatarFelix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: default avatarJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@mellanox.com>
parent fac555ac

drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c

+0 −1
Original line number Diff line number Diff line
@@ -818,7 +818,6 @@ 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;

	range->page_shift = PAGE_SHIFT;

	range->start = start;

	range->end = start + ttm->num_pages * PAGE_SIZE;

drivers/gpu/drm/nouveau/nouveau_svm.c

+0 −1
Original line number Diff line number Diff line
@@ -680,7 +680,6 @@ 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;

include/linux/hmm.h

+0 −22
Original line number Diff line number Diff line
@@ -158,7 +158,6 @@ enum hmm_pfn_value_e { 
 * @values: pfn value for some special case (none, special, error, ...)

 * @default_flags: default flags for the range (write, read, ... see hmm doc)

 * @pfn_flags_mask: allows to mask pfn flags so that only default_flags matter

 * @page_shift: device virtual address shift value (should be >= PAGE_SHIFT)

 * @pfn_shifts: pfn shift value (should be <= PAGE_SHIFT)

 * @valid: pfns array did not change since it has been fill by an HMM function

 */
@@ -172,31 +171,10 @@ struct hmm_range { 
	const uint64_t		*values;

	uint64_t		default_flags;

	uint64_t		pfn_flags_mask;

	uint8_t			page_shift;

	uint8_t			pfn_shift;

	bool			valid;

};



/*

 * hmm_range_page_shift() - return the page shift for the range

 * @range: range being queried

 * Return: page shift (page size = 1 << page shift) for the range

 */

static inline unsigned hmm_range_page_shift(const struct hmm_range *range)

{

	return range->page_shift;

}



/*

 * hmm_range_page_size() - return the page size for the range

 * @range: range being queried

 * Return: page size for the range in bytes

 */

static inline unsigned long hmm_range_page_size(const struct hmm_range *range)

{

	return 1UL << hmm_range_page_shift(range);

}



/*

 * hmm_range_wait_until_valid() - wait for range to be valid

 * @range: range affected by invalidation to wait on

mm/hmm.c

+9 −33
Original line number Diff line number Diff line
@@ -345,13 +345,12 @@ static int hmm_vma_walk_hole_(unsigned long addr, unsigned long end, 
	struct hmm_vma_walk *hmm_vma_walk = walk->private;

	struct hmm_range *range = hmm_vma_walk->range;

	uint64_t *pfns = range->pfns;

	unsigned long i, page_size;

	unsigned long i;



	hmm_vma_walk->last = addr;

	page_size = hmm_range_page_size(range);

	i = (addr - range->start) >> range->page_shift;

	i = (addr - range->start) >> PAGE_SHIFT;



	for (; addr < end; addr += page_size, i++) {

	for (; addr < end; addr += PAGE_SIZE, i++) {

		pfns[i] = range->values[HMM_PFN_NONE];

		if (fault || write_fault) {

			int ret;
@@ -779,7 +778,7 @@ static int hmm_vma_walk_hugetlb_entry(pte_t *pte, unsigned long hmask, 
				      struct mm_walk *walk)

{

#ifdef CONFIG_HUGETLB_PAGE

	unsigned long addr = start, i, pfn, mask, size, pfn_inc;

	unsigned long addr = start, i, pfn, mask;

	struct hmm_vma_walk *hmm_vma_walk = walk->private;

	struct hmm_range *range = hmm_vma_walk->range;

	struct vm_area_struct *vma = walk->vma;
@@ -790,24 +789,12 @@ static int hmm_vma_walk_hugetlb_entry(pte_t *pte, unsigned long hmask, 
	pte_t entry;

	int ret = 0;



	size = huge_page_size(h);

	mask = size - 1;

	if (range->page_shift != PAGE_SHIFT) {

		/* Make sure we are looking at a full page. */

		if (start & mask)

			return -EINVAL;

		if (end < (start + size))

			return -EINVAL;

		pfn_inc = size >> PAGE_SHIFT;

	} else {

		pfn_inc = 1;

		size = PAGE_SIZE;

	}

	mask = huge_page_size(h) - 1;



	ptl = huge_pte_lock(hstate_vma(vma), walk->mm, pte);

	entry = huge_ptep_get(pte);



	i = (start - range->start) >> range->page_shift;

	i = (start - range->start) >> PAGE_SHIFT;

	orig_pfn = range->pfns[i];

	range->pfns[i] = range->values[HMM_PFN_NONE];

	cpu_flags = pte_to_hmm_pfn_flags(range, entry);
@@ -819,8 +806,8 @@ static int hmm_vma_walk_hugetlb_entry(pte_t *pte, unsigned long hmask, 
		goto unlock;

	}



	pfn = pte_pfn(entry) + ((start & mask) >> range->page_shift);

	for (; addr < end; addr += size, i++, pfn += pfn_inc)

	pfn = pte_pfn(entry) + ((start & mask) >> PAGE_SHIFT);

	for (; addr < end; addr += PAGE_SIZE, i++, pfn++)

		range->pfns[i] = hmm_device_entry_from_pfn(range, pfn) |

				 cpu_flags;

	hmm_vma_walk->last = end;
@@ -857,14 +844,13 @@ static void hmm_pfns_clear(struct hmm_range *range, 
 */

int hmm_range_register(struct hmm_range *range, struct hmm_mirror *mirror)

{

	unsigned long mask = ((1UL << range->page_shift) - 1UL);

	struct hmm *hmm = mirror->hmm;

	unsigned long flags;



	range->valid = false;

	range->hmm = NULL;



	if ((range->start & mask) || (range->end & mask))

	if ((range->start & (PAGE_SIZE - 1)) || (range->end & (PAGE_SIZE - 1)))

		return -EINVAL;

	if (range->start >= range->end)

		return -EINVAL;
@@ -971,16 +957,6 @@ long hmm_range_fault(struct hmm_range *range, unsigned int flags) 
		if (vma == NULL || (vma->vm_flags & device_vma))

			return -EFAULT;



		if (is_vm_hugetlb_page(vma)) {

			if (huge_page_shift(hstate_vma(vma)) !=

			    range->page_shift &&

			    range->page_shift != PAGE_SHIFT)

				return -EINVAL;

		} else {

			if (range->page_shift != PAGE_SHIFT)

				return -EINVAL;

		}



		if (!(vma->vm_flags & VM_READ)) {

			/*

			 * If vma do not allow read access, then assume that it

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