Merge remote-tracking branch 'aio/master'

1 files changed, 25 insertions, 0 deletions

diff --git a/fs/aio.c b/fs/aio.c
index 84a751005f5b..47e1acca3b08 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -273,12 +273,37 @@ static void aio_free_ring(struct kioctx *ctx)
 
 static int aio_ring_mmap(struct file *file, struct vm_area_struct *vma)
 {
+	vma->vm_flags |= VM_DONTEXPAND;
 	vma->vm_ops = &generic_file_vm_ops;
 	return 0;
 }
 
+static void aio_ring_remap(struct file *file, struct vm_area_struct *vma)
+{
+	struct mm_struct *mm = vma->vm_mm;
+	struct kioctx_table *table;
+	int i;
+
+	spin_lock(&mm->ioctx_lock);
+	rcu_read_lock();
+	table = rcu_dereference(mm->ioctx_table);
+	for (i = 0; i < table->nr; i++) {
+		struct kioctx *ctx;
+
+		ctx = table->table[i];
+		if (ctx && ctx->aio_ring_file == file) {
+			ctx->user_id = ctx->mmap_base = vma->vm_start;
+			break;
+		}
+	}
+
+	rcu_read_unlock();
+	spin_unlock(&mm->ioctx_lock);
+}
+
 static const struct file_operations aio_ring_fops = {
 	.mmap = aio_ring_mmap,
+	.mremap = aio_ring_remap,
 };
 
 static int aio_set_page_dirty(struct page *page)