diff options
Diffstat (limited to 'drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c')
-rw-r--r-- | drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 145 |
1 files changed, 89 insertions, 56 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c index 80fc3d8ee1cf..445de594c214 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c @@ -35,6 +35,7 @@ #include <linux/hmm.h> #include <linux/pagemap.h> #include <linux/sched/task.h> +#include <linux/sched/mm.h> #include <linux/seq_file.h> #include <linux/slab.h> #include <linux/swap.h> @@ -769,6 +770,20 @@ struct amdgpu_ttm_tt { #endif }; +#ifdef CONFIG_DRM_AMDGPU_USERPTR +/* flags used by HMM internal, not related to CPU/GPU PTE flags */ +static const uint64_t hmm_range_flags[HMM_PFN_FLAG_MAX] = { + (1 << 0), /* HMM_PFN_VALID */ + (1 << 1), /* HMM_PFN_WRITE */ + 0 /* HMM_PFN_DEVICE_PRIVATE */ +}; + +static const uint64_t hmm_range_values[HMM_PFN_VALUE_MAX] = { + 0xfffffffffffffffeUL, /* HMM_PFN_ERROR */ + 0, /* HMM_PFN_NONE */ + 0xfffffffffffffffcUL /* HMM_PFN_SPECIAL */ +}; + /** * amdgpu_ttm_tt_get_user_pages - get device accessible pages that back user * memory and start HMM tracking CPU page table update @@ -776,85 +791,89 @@ 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 - int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages) { - struct hmm_mirror *mirror = bo->mn ? &bo->mn->mirror : NULL; struct ttm_tt *ttm = bo->tbo.ttm; struct amdgpu_ttm_tt *gtt = (void *)ttm; - struct mm_struct *mm = gtt->usertask->mm; unsigned long start = gtt->userptr; struct vm_area_struct *vma; struct hmm_range *range; + unsigned long timeout; + struct mm_struct *mm; unsigned long i; - uint64_t *pfns; int r = 0; - if (!mm) /* Happens during process shutdown */ - return -ESRCH; - - if (unlikely(!mirror)) { - DRM_DEBUG_DRIVER("Failed to get hmm_mirror\n"); - r = -EFAULT; - goto out; + mm = bo->notifier.mm; + if (unlikely(!mm)) { + DRM_DEBUG_DRIVER("BO is not registered?\n"); + return -EFAULT; } - vma = find_vma(mm, start); - if (unlikely(!vma || start < vma->vm_start)) { - r = -EFAULT; - goto out; - } - if (unlikely((gtt->userflags & AMDGPU_GEM_USERPTR_ANONONLY) && - vma->vm_file)) { - r = -EPERM; - goto out; - } + /* Another get_user_pages is running at the same time?? */ + if (WARN_ON(gtt->range)) + return -EFAULT; + + if (!mmget_not_zero(mm)) /* Happens during process shutdown */ + return -ESRCH; range = kzalloc(sizeof(*range), GFP_KERNEL); if (unlikely(!range)) { r = -ENOMEM; goto out; } + range->notifier = &bo->notifier; + range->flags = hmm_range_flags; + range->values = hmm_range_values; + range->pfn_shift = PAGE_SHIFT; + range->start = bo->notifier.interval_tree.start; + range->end = bo->notifier.interval_tree.last + 1; + range->default_flags = hmm_range_flags[HMM_PFN_VALID]; + if (!amdgpu_ttm_tt_is_readonly(ttm)) + range->default_flags |= range->flags[HMM_PFN_WRITE]; - pfns = kvmalloc_array(ttm->num_pages, sizeof(*pfns), GFP_KERNEL); - if (unlikely(!pfns)) { + range->pfns = kvmalloc_array(ttm->num_pages, sizeof(*range->pfns), + GFP_KERNEL); + if (unlikely(!range->pfns)) { r = -ENOMEM; goto out_free_ranges; } - amdgpu_hmm_init_range(range); - range->default_flags = range->flags[HMM_PFN_VALID]; - range->default_flags |= amdgpu_ttm_tt_is_readonly(ttm) ? - 0 : range->flags[HMM_PFN_WRITE]; - range->pfn_flags_mask = 0; - range->pfns = pfns; - range->start = start; - range->end = start + ttm->num_pages * PAGE_SIZE; - - hmm_range_register(range, mirror); + down_read(&mm->mmap_sem); + vma = find_vma(mm, start); + if (unlikely(!vma || start < vma->vm_start)) { + r = -EFAULT; + goto out_unlock; + } + if (unlikely((gtt->userflags & AMDGPU_GEM_USERPTR_ANONONLY) && + vma->vm_file)) { + r = -EPERM; + goto out_unlock; + } + up_read(&mm->mmap_sem); + timeout = jiffies + msecs_to_jiffies(HMM_RANGE_DEFAULT_TIMEOUT); - /* - * 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 - * mmap_sem to ascertain the validity of the range. - */ - hmm_range_wait_until_valid(range, HMM_RANGE_DEFAULT_TIMEOUT); +retry: + range->notifier_seq = mmu_interval_read_begin(&bo->notifier); down_read(&mm->mmap_sem); r = hmm_range_fault(range, 0); up_read(&mm->mmap_sem); - - if (unlikely(r < 0)) + if (unlikely(r <= 0)) { + /* + * FIXME: This timeout should encompass the retry from + * mmu_interval_read_retry() as well. + */ + if ((r == 0 || r == -EBUSY) && !time_after(jiffies, timeout)) + goto retry; goto out_free_pfns; + } for (i = 0; i < ttm->num_pages; i++) { - pages[i] = hmm_device_entry_to_page(range, pfns[i]); + /* FIXME: The pages cannot be touched outside the notifier_lock */ + pages[i] = hmm_device_entry_to_page(range, range->pfns[i]); if (unlikely(!pages[i])) { pr_err("Page fault failed for pfn[%lu] = 0x%llx\n", - i, pfns[i]); + i, range->pfns[i]); r = -ENOMEM; goto out_free_pfns; @@ -862,15 +881,18 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages) } gtt->range = range; + mmput(mm); return 0; +out_unlock: + up_read(&mm->mmap_sem); out_free_pfns: - hmm_range_unregister(range); - kvfree(pfns); + kvfree(range->pfns); out_free_ranges: kfree(range); out: + mmput(mm); return r; } @@ -895,15 +917,18 @@ bool amdgpu_ttm_tt_get_user_pages_done(struct ttm_tt *ttm) "No user pages to check\n"); if (gtt->range) { - r = hmm_range_valid(gtt->range); - hmm_range_unregister(gtt->range); - + /* + * FIXME: Must always hold notifier_lock for this, and must + * not ignore the return code. + */ + r = mmu_interval_read_retry(gtt->range->notifier, + gtt->range->notifier_seq); kvfree(gtt->range->pfns); kfree(gtt->range); gtt->range = NULL; } - return r; + return !r; } #endif @@ -984,10 +1009,18 @@ 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"); + if (gtt->range) { + unsigned long i; + + for (i = 0; i < ttm->num_pages; i++) { + if (ttm->pages[i] != + hmm_device_entry_to_page(gtt->range, + gtt->range->pfns[i])) + break; + } + + WARN((i == ttm->num_pages), "Missing get_user_page_done\n"); + } #endif } |