diff options
| -rw-r--r-- | mm/internal.h | 2 | ||||
| -rw-r--r-- | mm/mlock.c | 34 |
2 files changed, 24 insertions, 12 deletions
diff --git a/mm/internal.h b/mm/internal.h index 1c0c4cc0fcf..8562de0a519 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -195,7 +195,7 @@ static inline int mlocked_vma_newpage(struct vm_area_struct *vma, * must be called with vma's mmap_sem held for read or write, and page locked. */ extern void mlock_vma_page(struct page *page); -extern void munlock_vma_page(struct page *page); +extern unsigned int munlock_vma_page(struct page *page); /* * Clear the page's PageMlocked(). This can be useful in a situation where diff --git a/mm/mlock.c b/mm/mlock.c index e6638f565d4..1c5e33fce63 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -102,13 +102,16 @@ void mlock_vma_page(struct page *page) * can't isolate the page, we leave it for putback_lru_page() and vmscan * [page_referenced()/try_to_unmap()] to deal with. */ -void munlock_vma_page(struct page *page) +unsigned int munlock_vma_page(struct page *page) { + unsigned int page_mask = 0; + BUG_ON(!PageLocked(page)); if (TestClearPageMlocked(page)) { - mod_zone_page_state(page_zone(page), NR_MLOCK, - -hpage_nr_pages(page)); + unsigned int nr_pages = hpage_nr_pages(page); + mod_zone_page_state(page_zone(page), NR_MLOCK, -nr_pages); + page_mask = nr_pages - 1; if (!isolate_lru_page(page)) { int ret = SWAP_AGAIN; @@ -141,6 +144,8 @@ void munlock_vma_page(struct page *page) count_vm_event(UNEVICTABLE_PGMUNLOCKED); } } + + return page_mask; } /** @@ -159,7 +164,6 @@ long __mlock_vma_pages_range(struct vm_area_struct *vma, unsigned long start, unsigned long end, int *nonblocking) { struct mm_struct *mm = vma->vm_mm; - unsigned long addr = start; unsigned long nr_pages = (end - start) / PAGE_SIZE; int gup_flags; @@ -189,7 +193,7 @@ long __mlock_vma_pages_range(struct vm_area_struct *vma, * We made sure addr is within a VMA, so the following will * not result in a stack expansion that recurses back here. */ - return __get_user_pages(current, mm, addr, nr_pages, gup_flags, + return __get_user_pages(current, mm, start, nr_pages, gup_flags, NULL, NULL, nonblocking); } @@ -226,13 +230,12 @@ static int __mlock_posix_error_return(long retval) void munlock_vma_pages_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) { - unsigned long addr; - - lru_add_drain(); vma->vm_flags &= ~VM_LOCKED; - for (addr = start; addr < end; addr += PAGE_SIZE) { + while (start < end) { struct page *page; + unsigned int page_mask, page_increm; + /* * Although FOLL_DUMP is intended for get_dump_page(), * it just so happens that its special treatment of the @@ -240,13 +243,22 @@ void munlock_vma_pages_range(struct vm_area_struct *vma, * suits munlock very well (and if somehow an abnormal page * has sneaked into the range, we won't oops here: great). */ - page = follow_page(vma, addr, FOLL_GET | FOLL_DUMP); + page = follow_page_mask(vma, start, FOLL_GET | FOLL_DUMP, + &page_mask); if (page && !IS_ERR(page)) { lock_page(page); - munlock_vma_page(page); + lru_add_drain(); + /* + * Any THP page found by follow_page_mask() may have + * gotten split before reaching munlock_vma_page(), + * so we need to recompute the page_mask here. + */ + page_mask = munlock_vma_page(page); unlock_page(page); put_page(page); } + page_increm = 1 + (~(start >> PAGE_SHIFT) & page_mask); + start += page_increm * PAGE_SIZE; cond_resched(); } } |