author: Pavel Emelyanov <xemul@parallels.com> 2017-02-22 15:42:34 -0800
committer: Linus Torvalds <torvalds@linux-foundation.org> 2017-02-22 16:41:28 -0800
commit: 72f87654c69690ff4721bd9b4a39983f971de9a5
parent: d3aadc8ed4cb447981ecf34f9af71cddc6cf907d
Commit Summary:
Diffstat:
1 file changed, 30 insertions, 0 deletions
diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index 27978f249016..68f978beefac 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -596,6 +596,43 @@ void dup_userfaultfd_complete(struct list_head *fcs)
}
}
+void mremap_userfaultfd_prep(struct vm_area_struct *vma,
+ struct vm_userfaultfd_ctx *vm_ctx)
+{
+ struct userfaultfd_ctx *ctx;
+
+ ctx = vma->vm_userfaultfd_ctx.ctx;
+ if (ctx && (ctx->features & UFFD_FEATURE_EVENT_REMAP)) {
+ vm_ctx->ctx = ctx;
+ userfaultfd_ctx_get(ctx);
+ }
+}
+
+void mremap_userfaultfd_complete(struct vm_userfaultfd_ctx vm_ctx,
+ unsigned long from, unsigned long to,
+ unsigned long len)
+{
+ struct userfaultfd_ctx *ctx = vm_ctx.ctx;
+ struct userfaultfd_wait_queue ewq;
+
+ if (!ctx)
+ return;
+
+ if (to & ~PAGE_MASK) {
+ userfaultfd_ctx_put(ctx);
+ return;
+ }
+
+ msg_init(&ewq.msg);
+
+ ewq.msg.event = UFFD_EVENT_REMAP;
+ ewq.msg.arg.remap.from = from;
+ ewq.msg.arg.remap.to = to;
+ ewq.msg.arg.remap.len = len;
+
+ userfaultfd_event_wait_completion(ctx, &ewq);
+}
+
static int userfaultfd_release(struct inode *inode, struct file *file)
{
struct userfaultfd_ctx *ctx = file->private_data;