diff options
Diffstat (limited to 'mm/gup.c')
-rw-r--r-- | mm/gup.c | 92 |
1 files changed, 49 insertions, 43 deletions
@@ -811,7 +811,6 @@ static struct page *follow_page_mask(struct vm_area_struct *vma, struct follow_page_context *ctx) { pgd_t *pgd; - struct page *page; struct mm_struct *mm = vma->vm_mm; ctx->page_mask = 0; @@ -820,16 +819,10 @@ static struct page *follow_page_mask(struct vm_area_struct *vma, * Call hugetlb_follow_page_mask for hugetlb vmas as it will use * special hugetlb page table walking code. This eliminates the * need to check for hugetlb entries in the general walking code. - * - * hugetlb_follow_page_mask is only for follow_page() handling here. - * Ordinary GUP uses follow_hugetlb_page for hugetlb processing. */ - if (is_vm_hugetlb_page(vma)) { - page = hugetlb_follow_page_mask(vma, address, flags); - if (!page) - page = no_page_table(vma, flags); - return page; - } + if (is_vm_hugetlb_page(vma)) + return hugetlb_follow_page_mask(vma, address, flags, + &ctx->page_mask); pgd = pgd_offset(mm, address); @@ -1215,7 +1208,7 @@ static long __get_user_pages(struct mm_struct *mm, if (!vma && in_gate_area(mm, start)) { ret = get_gate_page(mm, start & PAGE_MASK, gup_flags, &vma, - pages ? &pages[i] : NULL); + pages ? &page : NULL); if (ret) goto out; ctx.page_mask = 0; @@ -1229,22 +1222,6 @@ static long __get_user_pages(struct mm_struct *mm, ret = check_vma_flags(vma, gup_flags); if (ret) goto out; - - if (is_vm_hugetlb_page(vma)) { - i = follow_hugetlb_page(mm, vma, pages, - &start, &nr_pages, i, - gup_flags, locked); - if (!*locked) { - /* - * We've got a VM_FAULT_RETRY - * and we've lost mmap_lock. - * We must stop here. - */ - BUG_ON(gup_flags & FOLL_NOWAIT); - goto out; - } - continue; - } } retry: /* @@ -1285,22 +1262,58 @@ retry: ret = PTR_ERR(page); goto out; } - - goto next_page; } else if (IS_ERR(page)) { ret = PTR_ERR(page); goto out; } - if (pages) { - pages[i] = page; - flush_anon_page(vma, page, start); - flush_dcache_page(page); - ctx.page_mask = 0; - } next_page: page_increm = 1 + (~(start >> PAGE_SHIFT) & ctx.page_mask); if (page_increm > nr_pages) page_increm = nr_pages; + + if (pages) { + struct page *subpage; + unsigned int j; + + /* + * This must be a large folio (and doesn't need to + * be the whole folio; it can be part of it), do + * the refcount work for all the subpages too. + * + * NOTE: here the page may not be the head page + * e.g. when start addr is not thp-size aligned. + * try_grab_folio() should have taken care of tail + * pages. + */ + if (page_increm > 1) { + struct folio *folio; + + /* + * Since we already hold refcount on the + * large folio, this should never fail. + */ + folio = try_grab_folio(page, page_increm - 1, + foll_flags); + if (WARN_ON_ONCE(!folio)) { + /* + * Release the 1st page ref if the + * folio is problematic, fail hard. + */ + gup_put_folio(page_folio(page), 1, + foll_flags); + ret = -EFAULT; + goto out; + } + } + + for (j = 0; j < page_increm; j++) { + subpage = nth_page(page, j); + pages[i + j] = subpage; + flush_anon_page(vma, subpage, start + j * PAGE_SIZE); + flush_dcache_page(subpage); + } + } + i += page_increm; start += page_increm * PAGE_SIZE; nr_pages -= page_increm; @@ -2231,13 +2244,6 @@ static bool is_valid_gup_args(struct page **pages, int *locked, gup_flags |= FOLL_UNLOCKABLE; } - /* - * For now, always trigger NUMA hinting faults. Some GUP users like - * KVM require the hint to be as the calling context of GUP is - * functionally similar to a memory reference from task context. - */ - gup_flags |= FOLL_HONOR_NUMA_FAULT; - /* FOLL_GET and FOLL_PIN are mutually exclusive. */ if (WARN_ON_ONCE((gup_flags & (FOLL_PIN | FOLL_GET)) == (FOLL_PIN | FOLL_GET))) @@ -2594,7 +2600,7 @@ static int gup_pte_range(pmd_t pmd, pmd_t *pmdp, unsigned long addr, if (!folio) goto pte_unmap; - if (unlikely(page_is_secretmem(page))) { + if (unlikely(folio_is_secretmem(folio))) { gup_put_folio(folio, 1, flags); goto pte_unmap; } |