Hi Jérôme, Ben, Felix and Jason, below is a series against the hmm tree which cleans up various minor bits and allows HMM_MIRROR to be built on all architectures. Diffstat: 11 files changed, 94 insertions(+), 210 deletions(-) A git tree is also available at: git://git.infradead.org/users/hch/misc.git hmm-cleanups.2 Gitweb: http://git.infradead.org/users/hch/misc.git/shortlog/refs/heads/hmm-cleanups.2 Changes since v1: - fix the cover letter subject - improve various patch descriptions - use svmm->mm in nouveau_range_fault - inverse the hmask field when using it - select HMM_MIRROR instead of making it a user visible option
Christoph Hellwig
2019-Aug-06 16:05 UTC
[Nouveau] [PATCH 01/15] amdgpu: remove -EAGAIN handling for hmm_range_fault
hmm_range_fault can only return -EAGAIN if called with the HMM_FAULT_ALLOW_RETRY flag, which amdgpu never does. Remove the handling for the -EAGAIN case with its non-standard locking scheme. Signed-off-by: Christoph Hellwig <hch at lst.de> Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> Reviewed-by: Felix Kuehling <Felix.Kuehling at amd.com> --- drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 23 +++-------------------- 1 file changed, 3 insertions(+), 20 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c index 12a59ac83f72..f0821638bbc6 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c @@ -778,7 +778,6 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages) struct hmm_range *range; unsigned long i; uint64_t *pfns; - int retry = 0; int r = 0; if (!mm) /* Happens during process shutdown */ @@ -822,7 +821,6 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages) hmm_range_register(range, mirror, start, start + ttm->num_pages * PAGE_SIZE, PAGE_SHIFT); -retry: /* * Just wait for range to be valid, safe to ignore return value as we * will use the return value of hmm_range_fault() below under the @@ -831,24 +829,12 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages) hmm_range_wait_until_valid(range, HMM_RANGE_DEFAULT_TIMEOUT); down_read(&mm->mmap_sem); - r = hmm_range_fault(range, 0); - if (unlikely(r < 0)) { - if (likely(r == -EAGAIN)) { - /* - * return -EAGAIN, mmap_sem is dropped - */ - if (retry++ < MAX_RETRY_HMM_RANGE_FAULT) - goto retry; - else - pr_err("Retry hmm fault too many times\n"); - } - - goto out_up_read; - } - up_read(&mm->mmap_sem); + if (unlikely(r < 0)) + goto out_free_pfns; + for (i = 0; i < ttm->num_pages; i++) { pages[i] = hmm_device_entry_to_page(range, pfns[i]); if (unlikely(!pages[i])) { @@ -864,9 +850,6 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages) return 0; -out_up_read: - if (likely(r != -EAGAIN)) - up_read(&mm->mmap_sem); out_free_pfns: hmm_range_unregister(range); kvfree(pfns); -- 2.20.1
Christoph Hellwig
2019-Aug-06 16:05 UTC
[Nouveau] [PATCH 02/15] amdgpu: don't initialize range->list in amdgpu_hmm_init_range
The list is used to add the range to another list as an entry in the core hmm code, and intended as a private member not exposed to drivers. There is no need to initialize it in a driver. Signed-off-by: Christoph Hellwig <hch at lst.de> Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> Reviewed-by: Felix Kuehling <Felix.Kuehling at amd.com> --- drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c index b698b423b25d..60b9fc9561d7 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c @@ -484,6 +484,5 @@ void amdgpu_hmm_init_range(struct hmm_range *range) range->flags = hmm_range_flags; range->values = hmm_range_values; range->pfn_shift = PAGE_SHIFT; - INIT_LIST_HEAD(&range->list); } } -- 2.20.1
Christoph Hellwig
2019-Aug-06 16:05 UTC
[Nouveau] [PATCH 03/15] nouveau: pass struct nouveau_svmm to nouveau_range_fault
We'll need the nouveau_svmm structure to improve the function soon. For now this allows using the svmm->mm reference to unlock the mmap_sem, and thus the same dereference chain that the caller uses to lock and unlock it. Signed-off-by: Christoph Hellwig <hch at lst.de> --- drivers/gpu/drm/nouveau/nouveau_svm.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.c b/drivers/gpu/drm/nouveau/nouveau_svm.c index a74530b5a523..98072fd48cf7 100644 --- a/drivers/gpu/drm/nouveau/nouveau_svm.c +++ b/drivers/gpu/drm/nouveau/nouveau_svm.c @@ -485,23 +485,23 @@ nouveau_range_done(struct hmm_range *range) } static int -nouveau_range_fault(struct hmm_mirror *mirror, struct hmm_range *range) +nouveau_range_fault(struct nouveau_svmm *svmm, struct hmm_range *range) { long ret; range->default_flags = 0; range->pfn_flags_mask = -1UL; - ret = hmm_range_register(range, mirror, + ret = hmm_range_register(range, &svmm->mirror, range->start, range->end, PAGE_SHIFT); if (ret) { - up_read(&range->hmm->mm->mmap_sem); + up_read(&svmm->mm->mmap_sem); return (int)ret; } if (!hmm_range_wait_until_valid(range, HMM_RANGE_DEFAULT_TIMEOUT)) { - up_read(&range->hmm->mm->mmap_sem); + up_read(&svmm->mm->mmap_sem); return -EBUSY; } @@ -509,7 +509,7 @@ nouveau_range_fault(struct hmm_mirror *mirror, struct hmm_range *range) if (ret <= 0) { if (ret == 0) ret = -EBUSY; - up_read(&range->hmm->mm->mmap_sem); + up_read(&svmm->mm->mmap_sem); hmm_range_unregister(range); return ret; } @@ -689,7 +689,7 @@ nouveau_svm_fault(struct nvif_notify *notify) range.values = nouveau_svm_pfn_values; range.pfn_shift = NVIF_VMM_PFNMAP_V0_ADDR_SHIFT; again: - ret = nouveau_range_fault(&svmm->mirror, &range); + ret = nouveau_range_fault(svmm, &range); if (ret == 0) { mutex_lock(&svmm->mutex); if (!nouveau_range_done(&range)) { -- 2.20.1
Christoph Hellwig
2019-Aug-06 16:05 UTC
[Nouveau] [PATCH 04/15] mm: remove the pgmap field from struct hmm_vma_walk
There is only a single place where the pgmap is passed over a function call, so replace it with local variables in the places where we deal with the pgmap. Signed-off-by: Christoph Hellwig <hch at lst.de> --- mm/hmm.c | 62 ++++++++++++++++++++++++-------------------------------- 1 file changed, 27 insertions(+), 35 deletions(-) diff --git a/mm/hmm.c b/mm/hmm.c index 9a908902e4cc..d66fa29b42e0 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -278,7 +278,6 @@ EXPORT_SYMBOL(hmm_mirror_unregister); struct hmm_vma_walk { struct hmm_range *range; - struct dev_pagemap *pgmap; unsigned long last; unsigned int flags; }; @@ -475,6 +474,7 @@ static int hmm_vma_handle_pmd(struct mm_walk *walk, #ifdef CONFIG_TRANSPARENT_HUGEPAGE struct hmm_vma_walk *hmm_vma_walk = walk->private; struct hmm_range *range = hmm_vma_walk->range; + struct dev_pagemap *pgmap = NULL; unsigned long pfn, npages, i; bool fault, write_fault; uint64_t cpu_flags; @@ -490,17 +490,14 @@ static int hmm_vma_handle_pmd(struct mm_walk *walk, pfn = pmd_pfn(pmd) + pte_index(addr); for (i = 0; addr < end; addr += PAGE_SIZE, i++, pfn++) { if (pmd_devmap(pmd)) { - hmm_vma_walk->pgmap = get_dev_pagemap(pfn, - hmm_vma_walk->pgmap); - if (unlikely(!hmm_vma_walk->pgmap)) + pgmap = get_dev_pagemap(pfn, pgmap); + if (unlikely(!pgmap)) return -EBUSY; } pfns[i] = hmm_device_entry_from_pfn(range, pfn) | cpu_flags; } - if (hmm_vma_walk->pgmap) { - put_dev_pagemap(hmm_vma_walk->pgmap); - hmm_vma_walk->pgmap = NULL; - } + if (pgmap) + put_dev_pagemap(pgmap); hmm_vma_walk->last = end; return 0; #else @@ -520,7 +517,7 @@ static inline uint64_t pte_to_hmm_pfn_flags(struct hmm_range *range, pte_t pte) static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, unsigned long end, pmd_t *pmdp, pte_t *ptep, - uint64_t *pfn) + uint64_t *pfn, struct dev_pagemap **pgmap) { struct hmm_vma_walk *hmm_vma_walk = walk->private; struct hmm_range *range = hmm_vma_walk->range; @@ -591,9 +588,8 @@ static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, goto fault; if (pte_devmap(pte)) { - hmm_vma_walk->pgmap = get_dev_pagemap(pte_pfn(pte), - hmm_vma_walk->pgmap); - if (unlikely(!hmm_vma_walk->pgmap)) + *pgmap = get_dev_pagemap(pte_pfn(pte), *pgmap); + if (unlikely(!*pgmap)) return -EBUSY; } else if (IS_ENABLED(CONFIG_ARCH_HAS_PTE_SPECIAL) && pte_special(pte)) { *pfn = range->values[HMM_PFN_SPECIAL]; @@ -604,10 +600,10 @@ static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, return 0; fault: - if (hmm_vma_walk->pgmap) { - put_dev_pagemap(hmm_vma_walk->pgmap); - hmm_vma_walk->pgmap = NULL; - } + if (*pgmap) + put_dev_pagemap(*pgmap); + *pgmap = NULL; + pte_unmap(ptep); /* Fault any virtual address we were asked to fault */ return hmm_vma_walk_hole_(addr, end, fault, write_fault, walk); @@ -620,6 +616,7 @@ static int hmm_vma_walk_pmd(pmd_t *pmdp, { struct hmm_vma_walk *hmm_vma_walk = walk->private; struct hmm_range *range = hmm_vma_walk->range; + struct dev_pagemap *pgmap = NULL; uint64_t *pfns = range->pfns; unsigned long addr = start, i; pte_t *ptep; @@ -683,23 +680,21 @@ static int hmm_vma_walk_pmd(pmd_t *pmdp, for (; addr < end; addr += PAGE_SIZE, ptep++, i++) { int r; - r = hmm_vma_handle_pte(walk, addr, end, pmdp, ptep, &pfns[i]); + r = hmm_vma_handle_pte(walk, addr, end, pmdp, ptep, &pfns[i], + &pgmap); if (r) { /* hmm_vma_handle_pte() did unmap pte directory */ hmm_vma_walk->last = addr; return r; } } - if (hmm_vma_walk->pgmap) { - /* - * We do put_dev_pagemap() here and not in hmm_vma_handle_pte() - * so that we can leverage get_dev_pagemap() optimization which - * will not re-take a reference on a pgmap if we already have - * one. - */ - put_dev_pagemap(hmm_vma_walk->pgmap); - hmm_vma_walk->pgmap = NULL; - } + /* + * We do put_dev_pagemap() here and not in hmm_vma_handle_pte() so that + * we can leverage the get_dev_pagemap() optimization which will not + * re-take a reference on a pgmap if we already have one. + */ + if (pgmap) + put_dev_pagemap(pgmap); pte_unmap(ptep - 1); hmm_vma_walk->last = addr; @@ -714,6 +709,7 @@ static int hmm_vma_walk_pud(pud_t *pudp, struct hmm_vma_walk *hmm_vma_walk = walk->private; struct hmm_range *range = hmm_vma_walk->range; unsigned long addr = start, next; + struct dev_pagemap *pgmap = NULL; pmd_t *pmdp; pud_t pud; int ret; @@ -744,17 +740,14 @@ static int hmm_vma_walk_pud(pud_t *pudp, pfn = pud_pfn(pud) + ((addr & ~PUD_MASK) >> PAGE_SHIFT); for (i = 0; i < npages; ++i, ++pfn) { - hmm_vma_walk->pgmap = get_dev_pagemap(pfn, - hmm_vma_walk->pgmap); - if (unlikely(!hmm_vma_walk->pgmap)) + pgmap = get_dev_pagemap(pfn, pgmap); + if (unlikely(!pgmap)) return -EBUSY; pfns[i] = hmm_device_entry_from_pfn(range, pfn) | cpu_flags; } - if (hmm_vma_walk->pgmap) { - put_dev_pagemap(hmm_vma_walk->pgmap); - hmm_vma_walk->pgmap = NULL; - } + if (pgmap) + put_dev_pagemap(pgmap); hmm_vma_walk->last = end; return 0; } @@ -1002,7 +995,6 @@ long hmm_range_fault(struct hmm_range *range, unsigned int flags) return -EPERM; } - hmm_vma_walk.pgmap = NULL; hmm_vma_walk.last = start; hmm_vma_walk.flags = flags; hmm_vma_walk.range = range; -- 2.20.1
Christoph Hellwig
2019-Aug-06 16:05 UTC
[Nouveau] [PATCH 05/15] mm: remove the unused vma argument to hmm_range_dma_unmap
Signed-off-by: Christoph Hellwig <hch at lst.de> Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> --- include/linux/hmm.h | 1 - mm/hmm.c | 2 -- 2 files changed, 3 deletions(-) diff --git a/include/linux/hmm.h b/include/linux/hmm.h index 82265118d94a..59be0aa2476d 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -422,7 +422,6 @@ long hmm_range_dma_map(struct hmm_range *range, dma_addr_t *daddrs, unsigned int flags); long hmm_range_dma_unmap(struct hmm_range *range, - struct vm_area_struct *vma, struct device *device, dma_addr_t *daddrs, bool dirty); diff --git a/mm/hmm.c b/mm/hmm.c index d66fa29b42e0..3a3852660757 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -1121,7 +1121,6 @@ EXPORT_SYMBOL(hmm_range_dma_map); /** * hmm_range_dma_unmap() - unmap range of that was map with hmm_range_dma_map() * @range: range being unmapped - * @vma: the vma against which the range (optional) * @device: device against which dma map was done * @daddrs: dma address of mapped pages * @dirty: dirty page if it had the write flag set @@ -1133,7 +1132,6 @@ EXPORT_SYMBOL(hmm_range_dma_map); * concurrent mmu notifier or sync_cpu_device_pagetables() to make progress. */ long hmm_range_dma_unmap(struct hmm_range *range, - struct vm_area_struct *vma, struct device *device, dma_addr_t *daddrs, bool dirty) -- 2.20.1
Christoph Hellwig
2019-Aug-06 16:05 UTC
[Nouveau] [PATCH 06/15] mm: remove superflous arguments from hmm_range_register
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 at lst.de> Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> Reviewed-by: Felix Kuehling <Felix.Kuehling at amd.com> --- 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 98072fd48cf7..41fad4719ac6 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(&svmm->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; -- 2.20.1
Christoph Hellwig
2019-Aug-06 16:05 UTC
[Nouveau] [PATCH 07/15] mm: 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. Signed-off-by: Christoph Hellwig <hch at lst.de> Acked-by: Felix Kuehling <Felix.Kuehling at amd.com> --- drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 1 - drivers/gpu/drm/nouveau/nouveau_svm.c | 1 - include/linux/hmm.h | 22 ------------- mm/hmm.c | 42 ++++++------------------- 4 files changed, 9 insertions(+), 57 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c index 71d6e7087b0b..8bf79288c4e2 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c @@ -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; diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.c b/drivers/gpu/drm/nouveau/nouveau_svm.c index 41fad4719ac6..668d4bd0c118 100644 --- a/drivers/gpu/drm/nouveau/nouveau_svm.c +++ b/drivers/gpu/drm/nouveau/nouveau_svm.c @@ -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; diff --git a/include/linux/hmm.h b/include/linux/hmm.h index c5b51376b453..51e18fbb8953 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -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 diff --git a/mm/hmm.c b/mm/hmm.c index 926735a3aef9..f26d6abc4ed2 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -344,13 +344,12 @@ 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; @@ -772,7 +771,7 @@ 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; @@ -783,24 +782,12 @@ 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); @@ -812,8 +799,8 @@ 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; @@ -850,14 +837,13 @@ 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; @@ -964,16 +950,6 @@ 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 -- 2.20.1
Christoph Hellwig
2019-Aug-06 16:05 UTC
[Nouveau] [PATCH 08/15] mm: remove the mask variable in hmm_vma_walk_hugetlb_entry
The pagewalk code already passes the value as the hmask parameter. Signed-off-by: Christoph Hellwig <hch at lst.de> --- mm/hmm.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/mm/hmm.c b/mm/hmm.c index f26d6abc4ed2..03d37e102e3b 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -771,19 +771,16 @@ 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; + unsigned long addr = start, i, pfn; struct hmm_vma_walk *hmm_vma_walk = walk->private; struct hmm_range *range = hmm_vma_walk->range; struct vm_area_struct *vma = walk->vma; - struct hstate *h = hstate_vma(vma); uint64_t orig_pfn, cpu_flags; bool fault, write_fault; spinlock_t *ptl; pte_t entry; int ret = 0; - mask = huge_page_size(h) - 1; - ptl = huge_pte_lock(hstate_vma(vma), walk->mm, pte); entry = huge_ptep_get(pte); @@ -799,7 +796,7 @@ static int hmm_vma_walk_hugetlb_entry(pte_t *pte, unsigned long hmask, goto unlock; } - pfn = pte_pfn(entry) + ((start & mask) >> PAGE_SHIFT); + pfn = pte_pfn(entry) + ((start & ~hmask) >> PAGE_SHIFT); for (; addr < end; addr += PAGE_SIZE, i++, pfn++) range->pfns[i] = hmm_device_entry_from_pfn(range, pfn) | cpu_flags; -- 2.20.1
Christoph Hellwig
2019-Aug-06 16:05 UTC
[Nouveau] [PATCH 09/15] mm: don't abuse pte_index() in hmm_vma_handle_pmd
pte_index is an internal arch helper in various architectures, without consistent semantics. Open code that calculation of a PMD index based on the virtual address instead. Signed-off-by: Christoph Hellwig <hch at lst.de> --- mm/hmm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/hmm.c b/mm/hmm.c index 03d37e102e3b..2083e4db46f5 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -486,7 +486,7 @@ static int hmm_vma_handle_pmd(struct mm_walk *walk, if (pmd_protnone(pmd) || fault || write_fault) return hmm_vma_walk_hole_(addr, end, fault, write_fault, walk); - pfn = pmd_pfn(pmd) + pte_index(addr); + pfn = pmd_pfn(pmd) + ((addr & ~PMD_MASK) >> PAGE_SHIFT); for (i = 0; addr < end; addr += PAGE_SIZE, i++, pfn++) { if (pmd_devmap(pmd)) { pgmap = get_dev_pagemap(pfn, pgmap); -- 2.20.1
Christoph Hellwig
2019-Aug-06 16:05 UTC
[Nouveau] [PATCH 10/15] mm: only define hmm_vma_walk_pud if needed
We only need the special pud_entry walker if PUD-sized hugepages and pte mappings are supported, else the common pagewalk code will take care of the iteration. Not implementing this callback reduced the amount of code compiled for non-x86 platforms, and also fixes compile failures with other architectures when helpers like pud_pfn are not implemented. Signed-off-by: Christoph Hellwig <hch at lst.de> Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> --- mm/hmm.c | 29 ++++++++++++++++------------- 1 file changed, 16 insertions(+), 13 deletions(-) diff --git a/mm/hmm.c b/mm/hmm.c index 2083e4db46f5..5e7afe685213 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -455,15 +455,6 @@ static inline uint64_t pmd_to_hmm_pfn_flags(struct hmm_range *range, pmd_t pmd) range->flags[HMM_PFN_VALID]; } -static inline uint64_t pud_to_hmm_pfn_flags(struct hmm_range *range, pud_t pud) -{ - if (!pud_present(pud)) - return 0; - return pud_write(pud) ? range->flags[HMM_PFN_VALID] | - range->flags[HMM_PFN_WRITE] : - range->flags[HMM_PFN_VALID]; -} - static int hmm_vma_handle_pmd(struct mm_walk *walk, unsigned long addr, unsigned long end, @@ -700,10 +691,19 @@ static int hmm_vma_walk_pmd(pmd_t *pmdp, return 0; } -static int hmm_vma_walk_pud(pud_t *pudp, - unsigned long start, - unsigned long end, - struct mm_walk *walk) +#if defined(CONFIG_ARCH_HAS_PTE_DEVMAP) && \ + defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD) +static inline uint64_t pud_to_hmm_pfn_flags(struct hmm_range *range, pud_t pud) +{ + if (!pud_present(pud)) + return 0; + return pud_write(pud) ? range->flags[HMM_PFN_VALID] | + range->flags[HMM_PFN_WRITE] : + range->flags[HMM_PFN_VALID]; +} + +static int hmm_vma_walk_pud(pud_t *pudp, unsigned long start, unsigned long end, + struct mm_walk *walk) { struct hmm_vma_walk *hmm_vma_walk = walk->private; struct hmm_range *range = hmm_vma_walk->range; @@ -765,6 +765,9 @@ static int hmm_vma_walk_pud(pud_t *pudp, return 0; } +#else +#define hmm_vma_walk_pud NULL +#endif static int hmm_vma_walk_hugetlb_entry(pte_t *pte, unsigned long hmask, unsigned long start, unsigned long end, -- 2.20.1
Christoph Hellwig
2019-Aug-06 16:05 UTC
[Nouveau] [PATCH 11/15] mm: cleanup the hmm_vma_handle_pmd stub
Stub out the whole function when CONFIG_TRANSPARENT_HUGEPAGE is not set to make the function easier to read. Signed-off-by: Christoph Hellwig <hch at lst.de> --- mm/hmm.c | 18 ++++++++---------- 1 file changed, 8 insertions(+), 10 deletions(-) diff --git a/mm/hmm.c b/mm/hmm.c index 5e7afe685213..4aa7135f1094 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -455,13 +455,10 @@ static inline uint64_t pmd_to_hmm_pfn_flags(struct hmm_range *range, pmd_t pmd) range->flags[HMM_PFN_VALID]; } -static int hmm_vma_handle_pmd(struct mm_walk *walk, - unsigned long addr, - unsigned long end, - uint64_t *pfns, - pmd_t pmd) -{ #ifdef CONFIG_TRANSPARENT_HUGEPAGE +static int hmm_vma_handle_pmd(struct mm_walk *walk, unsigned long addr, + unsigned long end, uint64_t *pfns, pmd_t pmd) +{ struct hmm_vma_walk *hmm_vma_walk = walk->private; struct hmm_range *range = hmm_vma_walk->range; struct dev_pagemap *pgmap = NULL; @@ -490,11 +487,12 @@ static int hmm_vma_handle_pmd(struct mm_walk *walk, put_dev_pagemap(pgmap); hmm_vma_walk->last = end; return 0; -#else - /* If THP is not enabled then we should never reach this code ! */ - return -EINVAL; -#endif } +#else /* CONFIG_TRANSPARENT_HUGEPAGE */ +/* stub to allow the code below to compile */ +int hmm_vma_handle_pmd(struct mm_walk *walk, unsigned long addr, + unsigned long end, uint64_t *pfns, pmd_t pmd); +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ static inline uint64_t pte_to_hmm_pfn_flags(struct hmm_range *range, pte_t pte) { -- 2.20.1
Christoph Hellwig
2019-Aug-06 16:05 UTC
[Nouveau] [PATCH 12/15] mm: cleanup the hmm_vma_walk_hugetlb_entry stub
Stub out the whole function and assign NULL to the .hugetlb_entry method if CONFIG_HUGETLB_PAGE is not set, as the method won't ever be called in that case. Signed-off-by: Christoph Hellwig <hch at lst.de> Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> --- mm/hmm.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/mm/hmm.c b/mm/hmm.c index 4aa7135f1094..dee99d0cc856 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -767,11 +767,11 @@ static int hmm_vma_walk_pud(pud_t *pudp, unsigned long start, unsigned long end, #define hmm_vma_walk_pud NULL #endif +#ifdef CONFIG_HUGETLB_PAGE static int hmm_vma_walk_hugetlb_entry(pte_t *pte, unsigned long hmask, unsigned long start, unsigned long end, struct mm_walk *walk) { -#ifdef CONFIG_HUGETLB_PAGE unsigned long addr = start, i, pfn; struct hmm_vma_walk *hmm_vma_walk = walk->private; struct hmm_range *range = hmm_vma_walk->range; @@ -810,10 +810,10 @@ static int hmm_vma_walk_hugetlb_entry(pte_t *pte, unsigned long hmask, return hmm_vma_walk_hole_(addr, end, fault, write_fault, walk); return ret; -#else /* CONFIG_HUGETLB_PAGE */ - return -EINVAL; -#endif } +#else +#define hmm_vma_walk_hugetlb_entry NULL +#endif /* CONFIG_HUGETLB_PAGE */ static void hmm_pfns_clear(struct hmm_range *range, uint64_t *pfns, -- 2.20.1
Christoph Hellwig
2019-Aug-06 16:05 UTC
[Nouveau] [PATCH 13/15] mm: allow HMM_MIRROR on all architectures with MMU
There isn't really any architecture specific code in this page table walk implementation, so drop the dependencies. Signed-off-by: Christoph Hellwig <hch at lst.de> Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> --- mm/Kconfig | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/mm/Kconfig b/mm/Kconfig index 56cec636a1fc..b18782be969c 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -677,8 +677,7 @@ config DEV_PAGEMAP_OPS config HMM_MIRROR bool "HMM mirror CPU page table into a device page table" - depends on (X86_64 || PPC64) - depends on MMU && 64BIT + depends on MMU select MMU_NOTIFIER help Select HMM_MIRROR if you want to mirror range of the CPU page table of a -- 2.20.1
Christoph Hellwig
2019-Aug-06 16:05 UTC
[Nouveau] [PATCH 14/15] mm: make HMM_MIRROR an implicit option
Make HMM_MIRROR an option that is selected by drivers wanting to use it instead of a user visible option as it is just a low-level implementation detail. Signed-off-by: Christoph Hellwig <hch at lst.de> --- drivers/gpu/drm/amd/amdgpu/Kconfig | 4 +++- drivers/gpu/drm/nouveau/Kconfig | 4 +++- mm/Kconfig | 14 ++++++-------- 3 files changed, 12 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/Kconfig b/drivers/gpu/drm/amd/amdgpu/Kconfig index f6e5c0282fc1..2e98c016cb47 100644 --- a/drivers/gpu/drm/amd/amdgpu/Kconfig +++ b/drivers/gpu/drm/amd/amdgpu/Kconfig @@ -27,7 +27,9 @@ config DRM_AMDGPU_CIK config DRM_AMDGPU_USERPTR bool "Always enable userptr write support" depends on DRM_AMDGPU - depends on HMM_MIRROR + depends on MMU + select HMM_MIRROR + select MMU_NOTIFIER help This option selects CONFIG_HMM and CONFIG_HMM_MIRROR if it isn't already selected to enabled full userptr support. diff --git a/drivers/gpu/drm/nouveau/Kconfig b/drivers/gpu/drm/nouveau/Kconfig index 96b9814e6d06..df4352c279ba 100644 --- a/drivers/gpu/drm/nouveau/Kconfig +++ b/drivers/gpu/drm/nouveau/Kconfig @@ -86,9 +86,11 @@ config DRM_NOUVEAU_SVM bool "(EXPERIMENTAL) Enable SVM (Shared Virtual Memory) support" depends on DEVICE_PRIVATE depends on DRM_NOUVEAU - depends on HMM_MIRROR + depends on MMU depends on STAGING + select HMM_MIRROR select MIGRATE_VMA_HELPER + select MMU_NOTIFIER default n help Say Y here if you want to enable experimental support for diff --git a/mm/Kconfig b/mm/Kconfig index b18782be969c..563436dc1f24 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -675,16 +675,14 @@ config MIGRATE_VMA_HELPER config DEV_PAGEMAP_OPS bool +# +# Helpers to mirror range of the CPU page tables of a process into device page +# tables. +# config HMM_MIRROR - bool "HMM mirror CPU page table into a device page table" + bool depends on MMU - select MMU_NOTIFIER - help - Select HMM_MIRROR if you want to mirror range of the CPU page table of a - process into a device page table. Here, mirror means "keep synchronized". - Prerequisites: the device must provide the ability to write-protect its - page tables (at PAGE_SIZE granularity), and must be able to recover from - the resulting potential page faults. + depends on MMU_NOTIFIER config DEVICE_PRIVATE bool "Unaddressable device memory (GPU memory, ...)" -- 2.20.1
Christoph Hellwig
2019-Aug-06 16:05 UTC
[Nouveau] [PATCH 15/15] amdgpu: remove CONFIG_DRM_AMDGPU_USERPTR
The option is just used to select HMM mirror support and has a very confusing help text. Just pull in the HMM mirror code by default instead. Signed-off-by: Christoph Hellwig <hch at lst.de> --- drivers/gpu/drm/Kconfig | 2 ++ drivers/gpu/drm/amd/amdgpu/Kconfig | 10 ---------- drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 6 ------ drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h | 12 ------------ 4 files changed, 2 insertions(+), 28 deletions(-) diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig index 1d80222587ad..319c1da2e74e 100644 --- a/drivers/gpu/drm/Kconfig +++ b/drivers/gpu/drm/Kconfig @@ -226,9 +226,11 @@ config DRM_AMDGPU select DRM_SCHED select DRM_TTM select POWER_SUPPLY + select HMM_MIRROR select HWMON select BACKLIGHT_CLASS_DEVICE select INTERVAL_TREE + select MMU_NOTIFIER select CHASH help Choose this option if you have a recent AMD Radeon graphics card. diff --git a/drivers/gpu/drm/amd/amdgpu/Kconfig b/drivers/gpu/drm/amd/amdgpu/Kconfig index 2e98c016cb47..c5c963164f5e 100644 --- a/drivers/gpu/drm/amd/amdgpu/Kconfig +++ b/drivers/gpu/drm/amd/amdgpu/Kconfig @@ -24,16 +24,6 @@ config DRM_AMDGPU_CIK radeon.cik_support=0 amdgpu.cik_support=1 -config DRM_AMDGPU_USERPTR - bool "Always enable userptr write support" - depends on DRM_AMDGPU - depends on MMU - select HMM_MIRROR - select MMU_NOTIFIER - help - This option selects CONFIG_HMM and CONFIG_HMM_MIRROR if it - isn't already selected to enabled full userptr support. - config DRM_AMDGPU_GART_DEBUGFS bool "Allow GART access through debugfs" depends on DRM_AMDGPU diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c index 8bf79288c4e2..00b74adbd790 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c @@ -751,9 +751,7 @@ struct amdgpu_ttm_tt { uint64_t userptr; struct task_struct *usertask; uint32_t userflags; -#if IS_ENABLED(CONFIG_DRM_AMDGPU_USERPTR) struct hmm_range *range; -#endif }; /** @@ -763,7 +761,6 @@ struct amdgpu_ttm_tt { * Calling function must call amdgpu_ttm_tt_userptr_range_done() once and only * once afterwards to stop HMM tracking */ -#if IS_ENABLED(CONFIG_DRM_AMDGPU_USERPTR) #define MAX_RETRY_HMM_RANGE_FAULT 16 @@ -892,7 +889,6 @@ bool amdgpu_ttm_tt_get_user_pages_done(struct ttm_tt *ttm) return r; } -#endif /** * amdgpu_ttm_tt_set_user_pages - Copy pages in, putting old pages as necessary. @@ -970,12 +966,10 @@ static void amdgpu_ttm_tt_unpin_userptr(struct ttm_tt *ttm) sg_free_table(ttm->sg); -#if IS_ENABLED(CONFIG_DRM_AMDGPU_USERPTR) if (gtt->range && ttm->pages[0] == hmm_device_entry_to_page(gtt->range, gtt->range->pfns[0])) WARN_ONCE(1, "Missing get_user_page_done\n"); -#endif } int amdgpu_ttm_gart_bind(struct amdgpu_device *adev, diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h index caa76c693700..406b1c5e6dd4 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h @@ -101,20 +101,8 @@ int amdgpu_mmap(struct file *filp, struct vm_area_struct *vma); int amdgpu_ttm_alloc_gart(struct ttm_buffer_object *bo); int amdgpu_ttm_recover_gart(struct ttm_buffer_object *tbo); -#if IS_ENABLED(CONFIG_DRM_AMDGPU_USERPTR) int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages); bool amdgpu_ttm_tt_get_user_pages_done(struct ttm_tt *ttm); -#else -static inline int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, - struct page **pages) -{ - return -EPERM; -} -static inline bool amdgpu_ttm_tt_get_user_pages_done(struct ttm_tt *ttm) -{ - return false; -} -#endif void amdgpu_ttm_tt_set_user_pages(struct ttm_tt *ttm, struct page **pages); int amdgpu_ttm_tt_set_userptr(struct ttm_tt *ttm, uint64_t addr, -- 2.20.1
Jason Gunthorpe
2019-Aug-06 17:44 UTC
[Nouveau] [PATCH 15/15] amdgpu: remove CONFIG_DRM_AMDGPU_USERPTR
On Tue, Aug 06, 2019 at 07:05:53PM +0300, Christoph Hellwig wrote:> The option is just used to select HMM mirror support and has a very > confusing help text. Just pull in the HMM mirror code by default > instead. > > Signed-off-by: Christoph Hellwig <hch at lst.de> > --- > drivers/gpu/drm/Kconfig | 2 ++ > drivers/gpu/drm/amd/amdgpu/Kconfig | 10 ---------- > drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 6 ------ > drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h | 12 ------------ > 4 files changed, 2 insertions(+), 28 deletions(-)Felix, was this an effort to avoid the arch restriction on hmm or something? Also can't see why this was like this. Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> Jason
Jason Gunthorpe
2019-Aug-06 17:44 UTC
[Nouveau] [PATCH 14/15] mm: make HMM_MIRROR an implicit option
On Tue, Aug 06, 2019 at 07:05:52PM +0300, Christoph Hellwig wrote:> Make HMM_MIRROR an option that is selected by drivers wanting to use it > instead of a user visible option as it is just a low-level > implementation detail. > > Signed-off-by: Christoph Hellwig <hch at lst.de> > --- > drivers/gpu/drm/amd/amdgpu/Kconfig | 4 +++- > drivers/gpu/drm/nouveau/Kconfig | 4 +++- > mm/Kconfig | 14 ++++++-------- > 3 files changed, 12 insertions(+), 10 deletions(-)Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> Jason
Jason Gunthorpe
2019-Aug-06 18:00 UTC
[Nouveau] [PATCH 11/15] mm: cleanup the hmm_vma_handle_pmd stub
On Tue, Aug 06, 2019 at 07:05:49PM +0300, Christoph Hellwig wrote:> Stub out the whole function when CONFIG_TRANSPARENT_HUGEPAGE is not set > to make the function easier to read. > > Signed-off-by: Christoph Hellwig <hch at lst.de> > --- > mm/hmm.c | 18 ++++++++---------- > 1 file changed, 8 insertions(+), 10 deletions(-)Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> Jason
Jason Gunthorpe
2019-Aug-06 18:02 UTC
[Nouveau] [PATCH 08/15] mm: remove the mask variable in hmm_vma_walk_hugetlb_entry
On Tue, Aug 06, 2019 at 07:05:46PM +0300, Christoph Hellwig wrote:> The pagewalk code already passes the value as the hmask parameter. > > Signed-off-by: Christoph Hellwig <hch at lst.de> > mm/hmm.c | 7 ++----- > 1 file changed, 2 insertions(+), 5 deletions(-)Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> Jason
Jason Gunthorpe
2019-Aug-06 18:02 UTC
[Nouveau] [PATCH 03/15] nouveau: pass struct nouveau_svmm to nouveau_range_fault
On Tue, Aug 06, 2019 at 07:05:41PM +0300, Christoph Hellwig wrote:> We'll need the nouveau_svmm structure to improve the function soon. > For now this allows using the svmm->mm reference to unlock the > mmap_sem, and thus the same dereference chain that the caller uses > to lock and unlock it. > > Signed-off-by: Christoph Hellwig <hch at lst.de> > --- > drivers/gpu/drm/nouveau/nouveau_svm.c | 12 ++++++------ > 1 file changed, 6 insertions(+), 6 deletions(-)Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> Jason
Jason Gunthorpe
2019-Aug-07 17:18 UTC
[Nouveau] [PATCH 09/15] mm: don't abuse pte_index() in hmm_vma_handle_pmd
On Tue, Aug 06, 2019 at 07:05:47PM +0300, Christoph Hellwig wrote:> pte_index is an internal arch helper in various architectures, > without consistent semantics. Open code that calculation of a PMD > index based on the virtual address instead. > > Signed-off-by: Christoph Hellwig <hch at lst.de> > --- > mm/hmm.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-)There sure are a lot of different ways to express this, but this one looks OK to me, at least the switch from the PTRS_PER_PTE expression in the x86 imlpementation to PMD_MASK looks equivalent Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> Jason
Jason Gunthorpe
2019-Aug-07 17:45 UTC
[Nouveau] [PATCH 04/15] mm: remove the pgmap field from struct hmm_vma_walk
On Tue, Aug 06, 2019 at 07:05:42PM +0300, Christoph Hellwig wrote:> There is only a single place where the pgmap is passed over a function > call, so replace it with local variables in the places where we deal > with the pgmap. > > Signed-off-by: Christoph Hellwig <hch at lst.de> > mm/hmm.c | 62 ++++++++++++++++++++++++-------------------------------- > 1 file changed, 27 insertions(+), 35 deletions(-) > > diff --git a/mm/hmm.c b/mm/hmm.c > index 9a908902e4cc..d66fa29b42e0 100644 > +++ b/mm/hmm.c > @@ -278,7 +278,6 @@ EXPORT_SYMBOL(hmm_mirror_unregister); > > struct hmm_vma_walk { > struct hmm_range *range; > - struct dev_pagemap *pgmap; > unsigned long last; > unsigned int flags; > }; > @@ -475,6 +474,7 @@ static int hmm_vma_handle_pmd(struct mm_walk *walk, > #ifdef CONFIG_TRANSPARENT_HUGEPAGE > struct hmm_vma_walk *hmm_vma_walk = walk->private; > struct hmm_range *range = hmm_vma_walk->range; > + struct dev_pagemap *pgmap = NULL; > unsigned long pfn, npages, i; > bool fault, write_fault; > uint64_t cpu_flags; > @@ -490,17 +490,14 @@ static int hmm_vma_handle_pmd(struct mm_walk *walk, > pfn = pmd_pfn(pmd) + pte_index(addr); > for (i = 0; addr < end; addr += PAGE_SIZE, i++, pfn++) { > if (pmd_devmap(pmd)) { > - hmm_vma_walk->pgmap = get_dev_pagemap(pfn, > - hmm_vma_walk->pgmap); > - if (unlikely(!hmm_vma_walk->pgmap)) > + pgmap = get_dev_pagemap(pfn, pgmap); > + if (unlikely(!pgmap)) > return -EBUSY;Unrelated to this patch, but what is the point of getting checking that the pgmap exists for the page and then immediately releasing it? This code has this pattern in several places. It feels racy> } > pfns[i] = hmm_device_entry_from_pfn(range, pfn) | cpu_flags; > } > - if (hmm_vma_walk->pgmap) { > - put_dev_pagemap(hmm_vma_walk->pgmap); > - hmm_vma_walk->pgmap = NULL;Putting the value in the hmm_vma_walk would have made some sense to me if the pgmap was not set to NULL all over the place. Then the most xa_loads would be eliminated, as I would expect the pgmap tends to be mostly uniform for these use cases. Is there some reason the pgmap ref can't be held across faulting/sleeping? ie like below. Anyhow, I looked over this pretty carefully and the change looks functionally OK, I just don't know why the code is like this in the first place. Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> diff --git a/mm/hmm.c b/mm/hmm.c index 9a908902e4cc38..4e30128c23a505 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -497,10 +497,6 @@ static int hmm_vma_handle_pmd(struct mm_walk *walk, } pfns[i] = hmm_device_entry_from_pfn(range, pfn) | cpu_flags; } - if (hmm_vma_walk->pgmap) { - put_dev_pagemap(hmm_vma_walk->pgmap); - hmm_vma_walk->pgmap = NULL; - } hmm_vma_walk->last = end; return 0; #else @@ -604,10 +600,6 @@ static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, return 0; fault: - if (hmm_vma_walk->pgmap) { - put_dev_pagemap(hmm_vma_walk->pgmap); - hmm_vma_walk->pgmap = NULL; - } pte_unmap(ptep); /* Fault any virtual address we were asked to fault */ return hmm_vma_walk_hole_(addr, end, fault, write_fault, walk); @@ -690,16 +682,6 @@ static int hmm_vma_walk_pmd(pmd_t *pmdp, return r; } } - if (hmm_vma_walk->pgmap) { - /* - * We do put_dev_pagemap() here and not in hmm_vma_handle_pte() - * so that we can leverage get_dev_pagemap() optimization which - * will not re-take a reference on a pgmap if we already have - * one. - */ - put_dev_pagemap(hmm_vma_walk->pgmap); - hmm_vma_walk->pgmap = NULL; - } pte_unmap(ptep - 1); hmm_vma_walk->last = addr; @@ -751,10 +733,6 @@ static int hmm_vma_walk_pud(pud_t *pudp, pfns[i] = hmm_device_entry_from_pfn(range, pfn) | cpu_flags; } - if (hmm_vma_walk->pgmap) { - put_dev_pagemap(hmm_vma_walk->pgmap); - hmm_vma_walk->pgmap = NULL; - } hmm_vma_walk->last = end; return 0; } @@ -1026,6 +1004,14 @@ long hmm_range_fault(struct hmm_range *range, unsigned int flags) /* Keep trying while the range is valid. */ } while (ret == -EBUSY && range->valid); + /* + * We do put_dev_pagemap() here so that we can leverage + * get_dev_pagemap() optimization which will not re-take a + * reference on a pgmap if we already have one. + */ + if (hmm_vma_walk->pgmap) + put_dev_pagemap(hmm_vma_walk->pgmap); + if (ret) { unsigned long i;
Jason Gunthorpe
2019-Aug-07 17:51 UTC
[Nouveau] [PATCH 07/15] mm: remove the page_shift member from struct hmm_range
On Tue, Aug 06, 2019 at 07:05:45PM +0300, Christoph Hellwig wrote:> 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. > > Signed-off-by: Christoph Hellwig <hch at lst.de> > Acked-by: Felix Kuehling <Felix.Kuehling at amd.com> > --- > drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 1 - > drivers/gpu/drm/nouveau/nouveau_svm.c | 1 - > include/linux/hmm.h | 22 ------------- > mm/hmm.c | 42 ++++++------------------- > 4 files changed, 9 insertions(+), 57 deletions(-)Having looked at ODP more closley this doesn't seem to match what it needs anyhow. It can keep using its checking algorithm> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c > index 71d6e7087b0b..8bf79288c4e2 100644 > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c > @@ -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; > > diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.c b/drivers/gpu/drm/nouveau/nouveau_svm.c > index 41fad4719ac6..668d4bd0c118 100644 > --- a/drivers/gpu/drm/nouveau/nouveau_svm.c > +++ b/drivers/gpu/drm/nouveau/nouveau_svm.c > @@ -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; > diff --git a/include/linux/hmm.h b/include/linux/hmm.h > index c5b51376b453..51e18fbb8953 100644 > --- a/include/linux/hmm.h > +++ b/include/linux/hmm.h > @@ -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 > diff --git a/mm/hmm.c b/mm/hmm.c > index 926735a3aef9..f26d6abc4ed2 100644 > --- a/mm/hmm.c > +++ b/mm/hmm.c > @@ -344,13 +344,12 @@ 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; > @@ -772,7 +771,7 @@ 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; > @@ -783,24 +782,12 @@ 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); > @@ -812,8 +799,8 @@ 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; > @@ -850,14 +837,13 @@ 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;PAGE_SIZE-1 == PAGE_MASK ? If yes I can fix it Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> Jason
On Tue, Aug 06, 2019 at 07:05:38PM +0300, Christoph Hellwig wrote:> > Hi Jérôme, Ben, Felix and Jason, > > below is a series against the hmm tree which cleans up various minor > bits and allows HMM_MIRROR to be built on all architectures. > > Diffstat: > > 11 files changed, 94 insertions(+), 210 deletions(-) > > A git tree is also available at: > > git://git.infradead.org/users/hch/misc.git hmm-cleanups.2 > > Gitweb: > > http://git.infradead.org/users/hch/misc.git/shortlog/refs/heads/hmm-cleanups.2 > > Changes since v1: > - fix the cover letter subject > - improve various patch descriptions > - use svmm->mm in nouveau_range_fault > - inverse the hmask field when using it > - select HMM_MIRROR instead of making it a user visible optionI think it is straightforward enough to move into -next, so applied to the hmm.git lets get some more reviewed-bys/tested-by though. For now I dropped 'remove the pgmap field from struct hmm_vma_walk' just to hear the followup and 'amdgpu: remove CONFIG_DRM_AMDGPU_USERPTR' until the AMD team Acks Thanks, Jason
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