Merge branch 'akpm' (patches from Andrew)

Merge fixes from Andrew Morton:
 "22 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (22 commits)
  epoll: restrict EPOLLEXCLUSIVE to POLLIN and POLLOUT
  radix-tree: fix oops after radix_tree_iter_retry
  MAINTAINERS: trim the file triggers for ABI/API
  dax: dirty inode only if required
  thp: make deferred_split_scan() work again
  mm: replace vma_lock_anon_vma with anon_vma_lock_read/write
  ocfs2/dlm: clear refmap bit of recovery lock while doing local recovery cleanup
  um: asm/page.h: remove the pte_high member from struct pte_t
  mm, hugetlb: don't require CMA for runtime gigantic pages
  mm/hugetlb: fix gigantic page initialization/allocation
  mm: downgrade VM_BUG in isolate_lru_page() to warning
  mempolicy: do not try to queue pages from !vma_migratable()
  mm, vmstat: fix wrong WQ sleep when memory reclaim doesn't make any progress
  vmstat: make vmstat_update deferrable
  mm, vmstat: make quiet_vmstat lighter
  mm/Kconfig: correct description of DEFERRED_STRUCT_PAGE_INIT
  memblock: don't mark memblock_phys_mem_size() as __init
  dump_stack: avoid potential deadlocks
  mm: validate_mm browse_rb SMP race condition
  m32r: fix build failure due to SMP and MMU
  ...

1 files changed, 32 insertions, 6 deletions

diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index ae1dbcf47e97..cde60741cad2 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -94,6 +94,11 @@
 /* Epoll private bits inside the event mask */
 #define EP_PRIVATE_BITS (EPOLLWAKEUP | EPOLLONESHOT | EPOLLET | EPOLLEXCLUSIVE)
 
+#define EPOLLINOUT_BITS (POLLIN | POLLOUT)
+
+#define EPOLLEXCLUSIVE_OK_BITS (EPOLLINOUT_BITS | POLLERR | POLLHUP | \
+				EPOLLWAKEUP | EPOLLET | EPOLLEXCLUSIVE)
+
 /* Maximum number of nesting allowed inside epoll sets */
 #define EP_MAX_NESTS 4
 
@@ -1068,7 +1073,22 @@ static int ep_poll_callback(wait_queue_t *wait, unsigned mode, int sync, void *k
 	 * wait list.
 	 */
 	if (waitqueue_active(&ep->wq)) {
-		ewake = 1;
+		if ((epi->event.events & EPOLLEXCLUSIVE) &&
+					!((unsigned long)key & POLLFREE)) {
+			switch ((unsigned long)key & EPOLLINOUT_BITS) {
+			case POLLIN:
+				if (epi->event.events & POLLIN)
+					ewake = 1;
+				break;
+			case POLLOUT:
+				if (epi->event.events & POLLOUT)
+					ewake = 1;
+				break;
+			case 0:
+				ewake = 1;
+				break;
+			}
+		}
 		wake_up_locked(&ep->wq);
 	}
 	if (waitqueue_active(&ep->poll_wait))
@@ -1875,9 +1895,13 @@ SYSCALL_DEFINE4(epoll_ctl, int, epfd, int, op, int, fd,
 	 * so EPOLLEXCLUSIVE is not allowed for a EPOLL_CTL_MOD operation.
 	 * Also, we do not currently supported nested exclusive wakeups.
 	 */
-	if ((epds.events & EPOLLEXCLUSIVE) && (op == EPOLL_CTL_MOD ||
-		(op == EPOLL_CTL_ADD && is_file_epoll(tf.file))))
-		goto error_tgt_fput;
+	if (epds.events & EPOLLEXCLUSIVE) {
+		if (op == EPOLL_CTL_MOD)
+			goto error_tgt_fput;
+		if (op == EPOLL_CTL_ADD && (is_file_epoll(tf.file) ||
+				(epds.events & ~EPOLLEXCLUSIVE_OK_BITS)))
+			goto error_tgt_fput;
+	}
 
 	/*
 	 * At this point it is safe to assume that the "private_data" contains
@@ -1950,8 +1974,10 @@ SYSCALL_DEFINE4(epoll_ctl, int, epfd, int, op, int, fd,
 		break;
 	case EPOLL_CTL_MOD:
 		if (epi) {
-			epds.events |= POLLERR | POLLHUP;
-			error = ep_modify(ep, epi, &epds);
+			if (!(epi->event.events & EPOLLEXCLUSIVE)) {
+				epds.events |= POLLERR | POLLHUP;
+				error = ep_modify(ep, epi, &epds);
+			}
 		} else
 			error = -ENOENT;
 		break;