diff options
author | Stephen Rothwell <sfr@canb.auug.org.au> | 2022-06-28 16:54:05 +1000 |
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committer | Stephen Rothwell <sfr@canb.auug.org.au> | 2022-06-28 16:54:05 +1000 |
commit | 5f9df76887bf8170e8844f1907c13fbbb30e9c36 (patch) | |
tree | 3b940f7e1c36605af69ffe3a3e9bc8fa53bd12a1 /mm/gup.c | |
parent | 8f850ad6cf932b8b5125f9585cb397e08403cccd (diff) | |
parent | 84b494dcbcc015419e629ced664d3b737e83336e (diff) | |
download | linux-next-akpm-base.tar.gz |
# Conflicts:
# include/linux/pagevec.h
Diffstat (limited to 'mm/gup.c')
-rw-r--r-- | mm/gup.c | 62 |
1 files changed, 52 insertions, 10 deletions
@@ -532,7 +532,11 @@ retry: } page = vm_normal_page(vma, address, pte); - if (!page && pte_devmap(pte) && (flags & (FOLL_GET | FOLL_PIN))) { + if ((flags & FOLL_LRU) && ((page && is_zone_device_page(page)) || + (!page && pte_devmap(pte)))) { + page = ERR_PTR(-EEXIST); + goto out; + } else if (!page && pte_devmap(pte) && (flags & (FOLL_GET | FOLL_PIN))) { /* * Only return device mapping pages in the FOLL_GET or FOLL_PIN * case since they are only valid while holding the pgmap @@ -1641,10 +1645,11 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors) if (!locked) { locked = 1; mmap_read_lock(mm); - vma = find_vma(mm, nstart); + vma = find_vma_intersection(mm, nstart, end); } else if (nstart >= vma->vm_end) - vma = vma->vm_next; - if (!vma || vma->vm_start >= end) + vma = find_vma_intersection(mm, vma->vm_end, end); + + if (!vma) break; /* * Set [nstart; nend) to intersection of desired address @@ -1923,14 +1928,48 @@ static long check_and_migrate_movable_pages(unsigned long nr_pages, continue; prev_folio = folio; - if (folio_is_pinnable(folio)) + /* + * Device private pages will get faulted in during gup so it + * shouldn't be possible to see one here. + */ + if (WARN_ON_ONCE(folio_is_device_private(folio))) { + ret = -EFAULT; + goto unpin_pages; + } + + /* + * Device coherent pages are managed by a driver and should not + * be pinned indefinitely as it prevents the driver moving the + * page. So when trying to pin with FOLL_LONGTERM instead try + * to migrate the page out of device memory. + */ + if (folio_is_device_coherent(folio)) { + WARN_ON_ONCE(PageCompound(&folio->page)); + + /* + * Migration will fail if the page is pinned, so convert + * the pin on the source page to a normal reference. + */ + if (gup_flags & FOLL_PIN) { + get_page(&folio->page); + unpin_user_page(&folio->page); + } + + pages[i] = migrate_device_page(&folio->page, gup_flags); + if (!pages[i]) { + ret = -EBUSY; + goto unpin_pages; + } continue; + } + if (folio_is_pinnable(folio)) + continue; /* * Try to move out any movable page before pinning the range. */ if (folio_test_hugetlb(folio)) { - if (!isolate_huge_page(&folio->page, + if (isolate_hugetlb(&folio->page, &movable_page_list)) isolation_error_count++; continue; @@ -1961,10 +2000,13 @@ static long check_and_migrate_movable_pages(unsigned long nr_pages, return nr_pages; unpin_pages: - if (gup_flags & FOLL_PIN) { - unpin_user_pages(pages, nr_pages); - } else { - for (i = 0; i < nr_pages; i++) + for (i = 0; i < nr_pages; i++) { + if (!pages[i]) + continue; + + if (gup_flags & FOLL_PIN) + unpin_user_page(pages[i]); + else put_page(pages[i]); } |