Merge branch 'akpm' (patches from Andrew)

Merge fixes from Andrew Morton:
 "20 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  rapidio/rio_cm: avoid GFP_KERNEL in atomic context
  Revert "ocfs2: bump up o2cb network protocol version"
  ocfs2: fix start offset to ocfs2_zero_range_for_truncate()
  cgroup: duplicate cgroup reference when cloning sockets
  mm: memcontrol: make per-cpu charge cache IRQ-safe for socket accounting
  ocfs2: fix double unlock in case retry after free truncate log
  fanotify: fix list corruption in fanotify_get_response()
  fsnotify: add a way to stop queueing events on group shutdown
  ocfs2: fix trans extend while free cached blocks
  ocfs2: fix trans extend while flush truncate log
  ipc/shm: fix crash if CONFIG_SHMEM is not set
  mm: fix the page_swap_info() BUG_ON check
  autofs: use dentry flags to block walks during expire
  MAINTAINERS: update email for VLYNQ bus entry
  mm: avoid endless recursion in dump_page()
  mm, thp: fix leaking mapped pte in __collapse_huge_page_swapin()
  khugepaged: fix use-after-free in collapse_huge_page()
  MAINTAINERS: Maik has moved
  ocfs2/dlm: fix race between convert and migration
  mem-hotplug: don't clear the only node in new_node_page()

11 files changed, 164 insertions, 112 deletions

diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c
index b493909..d8e6d42 100644
--- a/fs/autofs4/expire.c
+++ b/fs/autofs4/expire.c
@@ -417,6 +417,7 @@ static struct dentry *should_expire(struct dentry *dentry,
 	}
 	return NULL;
 }
+
 /*
  * Find an eligible tree to time-out
  * A tree is eligible if :-
@@ -432,6 +433,7 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb,
 	struct dentry *root = sb->s_root;
 	struct dentry *dentry;
 	struct dentry *expired;
+	struct dentry *found;
 	struct autofs_info *ino;
 
 	if (!root)
@@ -442,31 +444,46 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb,
 
 	dentry = NULL;
 	while ((dentry = get_next_positive_subdir(dentry, root))) {
+		int flags = how;
+
 		spin_lock(&sbi->fs_lock);
 		ino = autofs4_dentry_ino(dentry);
-		if (ino->flags & AUTOFS_INF_WANT_EXPIRE)
-			expired = NULL;
-		else
-			expired = should_expire(dentry, mnt, timeout, how);
-		if (!expired) {
+		if (ino->flags & AUTOFS_INF_WANT_EXPIRE) {
 			spin_unlock(&sbi->fs_lock);
 			continue;
 		}
+		spin_unlock(&sbi->fs_lock);
+
+		expired = should_expire(dentry, mnt, timeout, flags);
+		if (!expired)
+			continue;
+
+		spin_lock(&sbi->fs_lock);
 		ino = autofs4_dentry_ino(expired);
 		ino->flags |= AUTOFS_INF_WANT_EXPIRE;
 		spin_unlock(&sbi->fs_lock);
 		synchronize_rcu();
-		spin_lock(&sbi->fs_lock);
-		if (should_expire(expired, mnt, timeout, how)) {
-			if (expired != dentry)
-				dput(dentry);
-			goto found;
-		}
 
+		/* Make sure a reference is not taken on found if
+		 * things have changed.
+		 */
+		flags &= ~AUTOFS_EXP_LEAVES;
+		found = should_expire(expired, mnt, timeout, how);
+		if (!found || found != expired)
+			/* Something has changed, continue */
+			goto next;
+
+		if (expired != dentry)
+			dput(dentry);
+
+		spin_lock(&sbi->fs_lock);
+		goto found;
+next:
+		spin_lock(&sbi->fs_lock);
 		ino->flags &= ~AUTOFS_INF_WANT_EXPIRE;
+		spin_unlock(&sbi->fs_lock);
 		if (expired != dentry)
 			dput(expired);
-		spin_unlock(&sbi->fs_lock);
 	}
 	return NULL;
 
@@ -483,6 +500,7 @@ int autofs4_expire_wait(struct dentry *dentry, int rcu_walk)
 	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
 	struct autofs_info *ino = autofs4_dentry_ino(dentry);
 	int status;
+	int state;
 
 	/* Block on any pending expire */
 	if (!(ino->flags & AUTOFS_INF_WANT_EXPIRE))
@@ -490,8 +508,19 @@ int autofs4_expire_wait(struct dentry *dentry, int rcu_walk)
 	if (rcu_walk)
 		return -ECHILD;
 
+retry:
 	spin_lock(&sbi->fs_lock);
-	if (ino->flags & AUTOFS_INF_EXPIRING) {
+	state = ino->flags & (AUTOFS_INF_WANT_EXPIRE | AUTOFS_INF_EXPIRING);
+	if (state == AUTOFS_INF_WANT_EXPIRE) {
+		spin_unlock(&sbi->fs_lock);
+		/*
+		 * Possibly being selected for expire, wait until
+		 * it's selected or not.
+		 */
+		schedule_timeout_uninterruptible(HZ/10);
+		goto retry;
+	}
+	if (state & AUTOFS_INF_EXPIRING) {
 		spin_unlock(&sbi->fs_lock);
 
 		pr_debug("waiting for expire %p name=%pd\n", dentry, dentry);
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index d2f97ec..e0e5f7c 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -67,18 +67,7 @@ static int fanotify_get_response(struct fsnotify_group *group,
 
 	pr_debug("%s: group=%p event=%p\n", __func__, group, event);
 
-	wait_event(group->fanotify_data.access_waitq, event->response ||
-				atomic_read(&group->fanotify_data.bypass_perm));
-
-	if (!event->response) {	/* bypass_perm set */
-		/*
-		 * Event was canceled because group is being destroyed. Remove
-		 * it from group's event list because we are responsible for
-		 * freeing the permission event.
-		 */
-		fsnotify_remove_event(group, &event->fae.fse);
-		return 0;
-	}
+	wait_event(group->fanotify_data.access_waitq, event->response);
 
 	/* userspace responded, convert to something usable */
 	switch (event->response) {
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 8e8e6bc..a643138 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -358,16 +358,20 @@ static int fanotify_release(struct inode *ignored, struct file *file)
 
 #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
 	struct fanotify_perm_event_info *event, *next;
+	struct fsnotify_event *fsn_event;
 
 	/*
-	 * There may be still new events arriving in the notification queue
-	 * but since userspace cannot use fanotify fd anymore, no event can
-	 * enter or leave access_list by now.
+	 * Stop new events from arriving in the notification queue. since
+	 * userspace cannot use fanotify fd anymore, no event can enter or
+	 * leave access_list by now either.
 	 */
-	spin_lock(&group->fanotify_data.access_lock);
-
-	atomic_inc(&group->fanotify_data.bypass_perm);
+	fsnotify_group_stop_queueing(group);
 
+	/*
+	 * Process all permission events on access_list and notification queue
+	 * and simulate reply from userspace.
+	 */
+	spin_lock(&group->fanotify_data.access_lock);
 	list_for_each_entry_safe(event, next, &group->fanotify_data.access_list,
 				 fae.fse.list) {
 		pr_debug("%s: found group=%p event=%p\n", __func__, group,
@@ -379,12 +383,21 @@ static int fanotify_release(struct inode *ignored, struct file *file)
 	spin_unlock(&group->fanotify_data.access_lock);
 
 	/*
-	 * Since bypass_perm is set, newly queued events will not wait for
-	 * access response. Wake up the already sleeping ones now.
-	 * synchronize_srcu() in fsnotify_destroy_group() will wait for all
-	 * processes sleeping in fanotify_handle_event() waiting for access
-	 * response and thus also for all permission events to be freed.
+	 * Destroy all non-permission events. For permission events just
+	 * dequeue them and set the response. They will be freed once the
+	 * response is consumed and fanotify_get_response() returns.
 	 */
+	mutex_lock(&group->notification_mutex);
+	while (!fsnotify_notify_queue_is_empty(group)) {
+		fsn_event = fsnotify_remove_first_event(group);
+		if (!(fsn_event->mask & FAN_ALL_PERM_EVENTS))
+			fsnotify_destroy_event(group, fsn_event);
+		else
+			FANOTIFY_PE(fsn_event)->response = FAN_ALLOW;
+	}
+	mutex_unlock(&group->notification_mutex);
+
+	/* Response for all permission events it set, wakeup waiters */
 	wake_up(&group->fanotify_data.access_waitq);
 #endif
 
@@ -755,7 +768,6 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
 	spin_lock_init(&group->fanotify_data.access_lock);
 	init_waitqueue_head(&group->fanotify_data.access_waitq);
 	INIT_LIST_HEAD(&group->fanotify_data.access_list);
-	atomic_set(&group->fanotify_data.bypass_perm, 0);
 #endif
 	switch (flags & FAN_ALL_CLASS_BITS) {
 	case FAN_CLASS_NOTIF:
diff --git a/fs/notify/group.c b/fs/notify/group.c
index 3e2dd85..b47f7cf 100644
--- a/fs/notify/group.c
+++ b/fs/notify/group.c
@@ -40,6 +40,17 @@ static void fsnotify_final_destroy_group(struct fsnotify_group *group)
 }
 
 /*
+ * Stop queueing new events for this group. Once this function returns
+ * fsnotify_add_event() will not add any new events to the group's queue.
+ */
+void fsnotify_group_stop_queueing(struct fsnotify_group *group)
+{
+	mutex_lock(&group->notification_mutex);
+	group->shutdown = true;
+	mutex_unlock(&group->notification_mutex);
+}
+
+/*
  * Trying to get rid of a group. Remove all marks, flush all events and release
  * the group reference.
  * Note that another thread calling fsnotify_clear_marks_by_group() may still
@@ -47,6 +58,14 @@ static void fsnotify_final_destroy_group(struct fsnotify_group *group)
  */
 void fsnotify_destroy_group(struct fsnotify_group *group)
 {
+	/*
+	 * Stop queueing new events. The code below is careful enough to not
+	 * require this but fanotify needs to stop queuing events even before
+	 * fsnotify_destroy_group() is called and this makes the other callers
+	 * of fsnotify_destroy_group() to see the same behavior.
+	 */
+	fsnotify_group_stop_queueing(group);
+
 	/* clear all inode marks for this group, attach them to destroy_list */
 	fsnotify_detach_group_marks(group);
 
diff --git a/fs/notify/notification.c b/fs/notify/notification.c
index a95d8e0..e455e83 100644
--- a/fs/notify/notification.c
+++ b/fs/notify/notification.c
@@ -82,7 +82,8 @@ void fsnotify_destroy_event(struct fsnotify_group *group,
  * Add an event to the group notification queue.  The group can later pull this
  * event off the queue to deal with.  The function returns 0 if the event was
  * added to the queue, 1 if the event was merged with some other queued event,
- * 2 if the queue of events has overflown.
+ * 2 if the event was not queued - either the queue of events has overflown
+ * or the group is shutting down.
  */
 int fsnotify_add_event(struct fsnotify_group *group,
 		       struct fsnotify_event *event,
@@ -96,6 +97,11 @@ int fsnotify_add_event(struct fsnotify_group *group,
 
 	mutex_lock(&group->notification_mutex);
 
+	if (group->shutdown) {
+		mutex_unlock(&group->notification_mutex);
+		return 2;
+	}
+
 	if (group->q_len >= group->max_events) {
 		ret = 2;
 		/* Queue overflow event only if it isn't already queued */
@@ -126,21 +132,6 @@ queue:
 }
 
 /*
- * Remove @event from group's notification queue. It is the responsibility of
- * the caller to destroy the event.
- */
-void fsnotify_remove_event(struct fsnotify_group *group,
-			   struct fsnotify_event *event)
-{
-	mutex_lock(&group->notification_mutex);
-	if (!list_empty(&event->list)) {
-		list_del_init(&event->list);
-		group->q_len--;
-	}
-	mutex_unlock(&group->notification_mutex);
-}
-
-/*
  * Remove and return the first event from the notification list.  It is the
  * responsibility of the caller to destroy the obtained event
  */
diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index 7dabbc3..f165f86 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -5922,7 +5922,6 @@ bail:
 }
 
 static int ocfs2_replay_truncate_records(struct ocfs2_super *osb,
-					 handle_t *handle,
 					 struct inode *data_alloc_inode,
 					 struct buffer_head *data_alloc_bh)
 {
@@ -5935,11 +5934,19 @@ static int ocfs2_replay_truncate_records(struct ocfs2_super *osb,
 	struct ocfs2_truncate_log *tl;
 	struct inode *tl_inode = osb->osb_tl_inode;
 	struct buffer_head *tl_bh = osb->osb_tl_bh;
+	handle_t *handle;
 
 	di = (struct ocfs2_dinode *) tl_bh->b_data;
 	tl = &di->id2.i_dealloc;
 	i = le16_to_cpu(tl->tl_used) - 1;
 	while (i >= 0) {
+		handle = ocfs2_start_trans(osb, OCFS2_TRUNCATE_LOG_FLUSH_ONE_REC);
+		if (IS_ERR(handle)) {
+			status = PTR_ERR(handle);
+			mlog_errno(status);
+			goto bail;
+		}
+
 		/* Caller has given us at least enough credits to
 		 * update the truncate log dinode */
 		status = ocfs2_journal_access_di(handle, INODE_CACHE(tl_inode), tl_bh,
@@ -5974,12 +5981,7 @@ static int ocfs2_replay_truncate_records(struct ocfs2_super *osb,
 			}
 		}
 
-		status = ocfs2_extend_trans(handle,
-				OCFS2_TRUNCATE_LOG_FLUSH_ONE_REC);
-		if (status < 0) {
-			mlog_errno(status);
-			goto bail;
-		}
+		ocfs2_commit_trans(osb, handle);
 		i--;
 	}
 
@@ -5994,7 +5996,6 @@ int __ocfs2_flush_truncate_log(struct ocfs2_super *osb)
 {
 	int status;
 	unsigned int num_to_flush;
-	handle_t *handle;
 	struct inode *tl_inode = osb->osb_tl_inode;
 	struct inode *data_alloc_inode = NULL;
 	struct buffer_head *tl_bh = osb->osb_tl_bh;
@@ -6038,21 +6039,11 @@ int __ocfs2_flush_truncate_log(struct ocfs2_super *osb)
 		goto out_mutex;
 	}
 
-	handle = ocfs2_start_trans(osb, OCFS2_TRUNCATE_LOG_FLUSH_ONE_REC);
-	if (IS_ERR(handle)) {
-		status = PTR_ERR(handle);
-		mlog_errno(status);
-		goto out_unlock;
-	}
-
-	status = ocfs2_replay_truncate_records(osb, handle, data_alloc_inode,
+	status = ocfs2_replay_truncate_records(osb, data_alloc_inode,
 					       data_alloc_bh);
 	if (status < 0)
 		mlog_errno(status);
 
-	ocfs2_commit_trans(osb, handle);
-
-out_unlock:
 	brelse(data_alloc_bh);
 	ocfs2_inode_unlock(data_alloc_inode, 1);
 
@@ -6413,43 +6404,34 @@ static int ocfs2_free_cached_blocks(struct ocfs2_super *osb,
 		goto out_mutex;
 	}
 
-	handle = ocfs2_start_trans(osb, OCFS2_SUBALLOC_FREE);
-	if (IS_ERR(handle)) {
-		ret = PTR_ERR(handle);
-		mlog_errno(ret);
-		goto out_unlock;
-	}
-
 	while (head) {
 		if (head->free_bg)
 			bg_blkno = head->free_bg;
 		else
 			bg_blkno = ocfs2_which_suballoc_group(head->free_blk,
 							      head->free_bit);
+		handle = ocfs2_start_trans(osb, OCFS2_SUBALLOC_FREE);
+		if (IS_ERR(handle)) {
+			ret = PTR_ERR(handle);
+			mlog_errno(ret);
+			goto out_unlock;
+		}
+
 		trace_ocfs2_free_cached_blocks(
 		     (unsigned long long)head->free_blk, head->free_bit);
 
 		ret = ocfs2_free_suballoc_bits(handle, inode, di_bh,
 					       head->free_bit, bg_blkno, 1);
-		if (ret) {
+		if (ret)
 			mlog_errno(ret);
-			goto out_journal;
-		}
 
-		ret = ocfs2_extend_trans(handle, OCFS2_SUBALLOC_FREE);
-		if (ret) {
-			mlog_errno(ret);
-			goto out_journal;
-		}
+		ocfs2_commit_trans(osb, handle);
 
 		tmp = head;
 		head = head->free_next;
 		kfree(tmp);
 	}
 
-out_journal:
-	ocfs2_commit_trans(osb, handle);
-
 out_unlock:
 	ocfs2_inode_unlock(inode, 1);
 	brelse(di_bh);
diff --git a/fs/ocfs2/cluster/tcp_internal.h b/fs/ocfs2/cluster/tcp_internal.h
index 94b1836..b95e7df 100644
--- a/fs/ocfs2/cluster/tcp_internal.h
+++ b/fs/ocfs2/cluster/tcp_internal.h
@@ -44,9 +44,6 @@
  * version here in tcp_internal.h should not need to be bumped for
  * filesystem locking changes.
  *
- * New in version 12
- *	- Negotiate hb timeout when storage is down.
- *
  * New in version 11
  * 	- Negotiation of filesystem locking in the dlm join.
  *
@@ -78,7 +75,7 @@
  * 	- full 64 bit i_size in the metadata lock lvbs
  * 	- introduction of "rw" lock and pushing meta/data locking down
  */
-#define O2NET_PROTOCOL_VERSION 12ULL
+#define O2NET_PROTOCOL_VERSION 11ULL
 struct o2net_handshake {
 	__be64	protocol_version;
 	__be64	connector_id;
diff --git a/fs/ocfs2/dlm/dlmconvert.c b/fs/ocfs2/dlm/dlmconvert.c
index cdeafb4..0bb1286 100644
--- a/fs/ocfs2/dlm/dlmconvert.c
+++ b/fs/ocfs2/dlm/dlmconvert.c
@@ -268,7 +268,6 @@ enum dlm_status dlmconvert_remote(struct dlm_ctxt *dlm,
 				  struct dlm_lock *lock, int flags, int type)
 {
 	enum dlm_status status;
-	u8 old_owner = res->owner;
 
 	mlog(0, "type=%d, convert_type=%d, busy=%d\n", lock->ml.type,
 	     lock->ml.convert_type, res->state & DLM_LOCK_RES_IN_PROGRESS);
@@ -335,7 +334,6 @@ enum dlm_status dlmconvert_remote(struct dlm_ctxt *dlm,
 
 	spin_lock(&res->spinlock);
 	res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
-	lock->convert_pending = 0;
 	/* if it failed, move it back to granted queue.
 	 * if master returns DLM_NORMAL and then down before sending ast,
 	 * it may have already been moved to granted queue, reset to
@@ -344,12 +342,14 @@ enum dlm_status dlmconvert_remote(struct dlm_ctxt *dlm,
 		if (status != DLM_NOTQUEUED)
 			dlm_error(status);
 		dlm_revert_pending_convert(res, lock);
-	} else if ((res->state & DLM_LOCK_RES_RECOVERING) ||
-			(old_owner != res->owner)) {
-		mlog(0, "res %.*s is in recovering or has been recovered.\n",
-				res->lockname.len, res->lockname.name);
+	} else if (!lock->convert_pending) {
+		mlog(0, "%s: res %.*s, owner died and lock has been moved back "
+				"to granted list, retry convert.\n",
+				dlm->name, res->lockname.len, res->lockname.name);
 		status = DLM_RECOVERING;
 	}
+
+	lock->convert_pending = 0;
 bail:
 	spin_unlock(&res->spinlock);
 
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 4e7b0dc..0b055bf 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1506,7 +1506,8 @@ static int ocfs2_zero_partial_clusters(struct inode *inode,
 				       u64 start, u64 len)
 {
 	int ret = 0;
-	u64 tmpend, end = start + len;
+	u64 tmpend = 0;
+	u64 end = start + len;
 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 	unsigned int csize = osb->s_clustersize;
 	handle_t *handle;
@@ -1538,18 +1539,31 @@ static int ocfs2_zero_partial_clusters(struct inode *inode,
 	}
 
 	/*
-	 * We want to get the byte offset of the end of the 1st cluster.
+	 * If start is on a cluster boundary and end is somewhere in another
+	 * cluster, we have not COWed the cluster starting at start, unless
+	 * end is also within the same cluster. So, in this case, we skip this
+	 * first call to ocfs2_zero_range_for_truncate() truncate and move on
+	 * to the next one.
 	 */
-	tmpend = (u64)osb->s_clustersize + (start & ~(osb->s_clustersize - 1));
-	if (tmpend > end)
-		tmpend = end;
+	if ((start & (csize - 1)) != 0) {
+		/*
+		 * We want to get the byte offset of the end of the 1st
+		 * cluster.
+		 */
+		tmpend = (u64)osb->s_clustersize +
+			(start & ~(osb->s_clustersize - 1));
+		if (tmpend > end)
+			tmpend = end;
 
-	trace_ocfs2_zero_partial_clusters_range1((unsigned long long)start,
-						 (unsigned long long)tmpend);
+		trace_ocfs2_zero_partial_clusters_range1(
+			(unsigned long long)start,
+			(unsigned long long)tmpend);
 
-	ret = ocfs2_zero_range_for_truncate(inode, handle, start, tmpend);
-	if (ret)
-		mlog_errno(ret);
+		ret = ocfs2_zero_range_for_truncate(inode, handle, start,
+						    tmpend);
+		if (ret)
+			mlog_errno(ret);
+	}
 
 	if (tmpend < end) {
 		/*
diff --git a/fs/ocfs2/suballoc.c b/fs/ocfs2/suballoc.c
index ea47120..6ad3533 100644
--- a/fs/ocfs2/suballoc.c
+++ b/fs/ocfs2/suballoc.c
@@ -1199,14 +1199,24 @@ retry:
 			inode_unlock((*ac)->ac_inode);
 
 			ret = ocfs2_try_to_free_truncate_log(osb, bits_wanted);
-			if (ret == 1)
+			if (ret == 1) {
+				iput((*ac)->ac_inode);
+				(*ac)->ac_inode = NULL;
 				goto retry;
+			}
 
 			if (ret < 0)
 				mlog_errno(ret);
 
 			inode_lock((*ac)->ac_inode);
-			ocfs2_inode_lock((*ac)->ac_inode, NULL, 1);
+			ret = ocfs2_inode_lock((*ac)->ac_inode, NULL, 1);
+			if (ret < 0) {
+				mlog_errno(ret);
+				inode_unlock((*ac)->ac_inode);
+				iput((*ac)->ac_inode);
+				(*ac)->ac_inode = NULL;
+				goto bail;
+			}
 		}
 		if (status < 0) {
 			if (status != -ENOSPC)
diff --git a/fs/ramfs/file-mmu.c b/fs/ramfs/file-mmu.c
index 183a212..12af049 100644
--- a/fs/ramfs/file-mmu.c
+++ b/fs/ramfs/file-mmu.c
@@ -27,9 +27,17 @@
 #include <linux/fs.h>
 #include <linux/mm.h>
 #include <linux/ramfs.h>
+#include <linux/sched.h>
 
 #include "internal.h"
 
+static unsigned long ramfs_mmu_get_unmapped_area(struct file *file,
+		unsigned long addr, unsigned long len, unsigned long pgoff,
+		unsigned long flags)
+{
+	return current->mm->get_unmapped_area(file, addr, len, pgoff, flags);
+}
+
 const struct file_operations ramfs_file_operations = {
 	.read_iter	= generic_file_read_iter,
 	.write_iter	= generic_file_write_iter,
@@ -38,6 +46,7 @@ const struct file_operations ramfs_file_operations = {
 	.splice_read	= generic_file_splice_read,
 	.splice_write	= iter_file_splice_write,
 	.llseek		= generic_file_llseek,
+	.get_unmapped_area	= ramfs_mmu_get_unmapped_area,
 };
 
 const struct inode_operations ramfs_file_inode_operations = {