diff --git a/src/tools/kernel/nk900xm-patch/fs/pipe.c b/src/tools/kernel/nk900xm-patch/fs/pipe.c
index 7087310e1278..d2c45e14e6d8 100644
--- a/src/tools/kernel/nk900xm-patch/fs/pipe.c
+++ b/src/tools/kernel/nk900xm-patch/fs/pipe.c
@@ -28,10 +28,6 @@
 
 #include "internal.h"
 
-extern size_t copy_page_to_iter(struct page *page,
-				size_t offset,
-				size_t bytes,
-				struct iov_iter *i);
 /*
  * The max size that a non-root user is allowed to grow the pipe. Can
  * be set by root in /proc/sys/fs/pipe-max-size
@@ -146,6 +142,55 @@ pipe_iov_copy_from_user(void *to, struct iovec *iov, unsigned long len,
 	return 0;
 }
 
+static int
+pipe_iov_copy_to_user(struct iovec *iov, const void *from, unsigned long len,
+		      int atomic)
+{
+	unsigned long copy;
+
+	while (len > 0) {
+		while (!iov->iov_len)
+			iov++;
+		copy = min_t(unsigned long, len, iov->iov_len);
+
+		if (atomic) {
+			if (__copy_to_user_inatomic(iov->iov_base, from, copy))
+				return -EFAULT;
+		} else {
+			if (copy_to_user(iov->iov_base, from, copy))
+				return -EFAULT;
+		}
+		from += copy;
+		len -= copy;
+		iov->iov_base += copy;
+		iov->iov_len -= copy;
+	}
+	return 0;
+}
+
+/*
+ * Attempt to pre-fault in the user memory, so we can use atomic copies.
+ * Returns the number of bytes not faulted in.
+ */
+static int iov_fault_in_pages_write(struct iovec *iov, unsigned long len)
+{
+	while (!iov->iov_len)
+		iov++;
+
+	while (len > 0) {
+		unsigned long this_len;
+
+		this_len = min_t(unsigned long, len, iov->iov_len);
+		if (fault_in_pages_writeable(iov->iov_base, this_len))
+			break;
+
+		len -= this_len;
+		iov++;
+	}
+
+	return len;
+}
+
 /*
  * Pre-fault in the user memory, so we can use atomic copies.
  */
@@ -334,15 +379,12 @@ pipe_read(struct kiocb *iocb, const struct iovec *_iov,
 	ssize_t ret;
 	struct iovec *iov = (struct iovec *)_iov;
 	size_t total_len;
-	struct iov_iter iter;
 
 	total_len = iov_length(iov, nr_segs);
 	/* Null read succeeds. */
 	if (unlikely(total_len == 0))
 		return 0;
 
-	iov_iter_init(&iter, iov, nr_segs, total_len, 0);
-
 	do_wakeup = 0;
 	ret = 0;
 	__pipe_lock(pipe);
@@ -352,9 +394,9 @@ pipe_read(struct kiocb *iocb, const struct iovec *_iov,
 			int curbuf = pipe->curbuf;
 			struct pipe_buffer *buf = pipe->bufs + curbuf;
 			const struct pipe_buf_operations *ops = buf->ops;
+			void *addr;
 			size_t chars = buf->len;
-			size_t written;
-			int error;
+			int error, atomic;
 
 			if (chars > total_len)
 				chars = total_len;
@@ -366,11 +408,21 @@ pipe_read(struct kiocb *iocb, const struct iovec *_iov,
 				break;
 			}
 
-			written = copy_page_to_iter(buf->page, buf->offset,
-						chars, &iter);
-			if (unlikely(written < chars)) {
+			atomic = !iov_fault_in_pages_write(iov, chars);
+redo:
+			addr = ops->map(pipe, buf, atomic);
+			error = pipe_iov_copy_to_user(iov, addr + buf->offset, chars, atomic);
+			ops->unmap(pipe, buf, addr);
+			if (unlikely(error)) {
+				/*
+				 * Just retry with the slow path if we failed.
+				 */
+				if (atomic) {
+					atomic = 0;
+					goto redo;
+				}
 				if (!ret)
-					ret = -EFAULT;
+					ret = error;
 				break;
 			}
 			ret += chars;
diff --git a/src/tools/kernel/nk900xm-patch/include/linux/fs.h b/src/tools/kernel/nk900xm-patch/include/linux/fs.h
index 40ff2b1eab4f..65c2be22b601 100644
--- a/src/tools/kernel/nk900xm-patch/include/linux/fs.h
+++ b/src/tools/kernel/nk900xm-patch/include/linux/fs.h
@@ -288,21 +288,11 @@ struct page;
 struct address_space;
 struct writeback_control;
 
-/*struct iov_iter {
+struct iov_iter {
 	const struct iovec *iov;
 	unsigned long nr_segs;
 	size_t iov_offset;
 	size_t count;
-};*/
-struct iov_iter {
-	int type;
-	size_t iov_offset;
-	size_t count;
-	union {
-		const struct iovec *iov;
-		const struct bio_vec *bvec;
-	};
-	unsigned long nr_segs;
 };
 
 size_t iov_iter_copy_from_user_atomic(struct page *page,
diff --git a/src/tools/kernel/nk900xm-patch/include/linux/uio.h b/src/tools/kernel/nk900xm-patch/include/linux/uio.h
index 627444f27ef0..c55ce243cc09 100644
--- a/src/tools/kernel/nk900xm-patch/include/linux/uio.h
+++ b/src/tools/kernel/nk900xm-patch/include/linux/uio.h
@@ -9,7 +9,6 @@
 #ifndef __LINUX_UIO_H
 #define __LINUX_UIO_H
 
-#include <linux/kernel.h>
 #include <uapi/linux/uio.h>
 
 
@@ -18,12 +17,6 @@ struct kvec {
 	size_t iov_len;
 };
 
-enum {
-	ITER_IOVEC = 0,
-	ITER_KVEC = 2,
-	ITER_BVEC = 4,
-};
-
 /*
  * Total number of bytes covered by an iovec.
  *
diff --git a/src/tools/kernel/nk900xm-patch/mm/Makefile b/src/tools/kernel/nk900xm-patch/mm/Makefile
index be01e8c7b89c..72c5acb9345f 100644
--- a/src/tools/kernel/nk900xm-patch/mm/Makefile
+++ b/src/tools/kernel/nk900xm-patch/mm/Makefile
@@ -17,7 +17,7 @@ obj-y			:= filemap.o mempool.o oom_kill.o fadvise.o \
 			   util.o mmzone.o vmstat.o backing-dev.o \
 			   mm_init.o mmu_context.o percpu.o slab_common.o \
 			   compaction.o balloon_compaction.o \
-			   iov_iter.o interval_tree.o $(mmu-y)
+			   interval_tree.o $(mmu-y)
 
 obj-y += init-mm.o