1 files changed, 16 insertions, 117 deletions

diff --git a/fs/pipe.c b/fs/pipe.c
index 78fd0d0788db..034bffac3f97 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -142,55 +142,6 @@ 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.
  */
@@ -226,52 +177,6 @@ static void anon_pipe_buf_release(struct pipe_inode_info *pipe,
 }
 
 /**
- * generic_pipe_buf_map - virtually map a pipe buffer
- * @pipe:	the pipe that the buffer belongs to
- * @buf:	the buffer that should be mapped
- * @atomic:	whether to use an atomic map
- *
- * Description:
- *	This function returns a kernel virtual address mapping for the
- *	pipe_buffer passed in @buf. If @atomic is set, an atomic map is provided
- *	and the caller has to be careful not to fault before calling
- *	the unmap function.
- *
- *	Note that this function calls kmap_atomic() if @atomic != 0.
- */
-void *generic_pipe_buf_map(struct pipe_inode_info *pipe,
-			   struct pipe_buffer *buf, int atomic)
-{
-	if (atomic) {
-		buf->flags |= PIPE_BUF_FLAG_ATOMIC;
-		return kmap_atomic(buf->page);
-	}
-
-	return kmap(buf->page);
-}
-EXPORT_SYMBOL(generic_pipe_buf_map);
-
-/**
- * generic_pipe_buf_unmap - unmap a previously mapped pipe buffer
- * @pipe:	the pipe that the buffer belongs to
- * @buf:	the buffer that should be unmapped
- * @map_data:	the data that the mapping function returned
- *
- * Description:
- *	This function undoes the mapping that ->map() provided.
- */
-void generic_pipe_buf_unmap(struct pipe_inode_info *pipe,
-			    struct pipe_buffer *buf, void *map_data)
-{
-	if (buf->flags & PIPE_BUF_FLAG_ATOMIC) {
-		buf->flags &= ~PIPE_BUF_FLAG_ATOMIC;
-		kunmap_atomic(map_data);
-	} else
-		kunmap(buf->page);
-}
-EXPORT_SYMBOL(generic_pipe_buf_unmap);
-
-/**
  * generic_pipe_buf_steal - attempt to take ownership of a &pipe_buffer
  * @pipe:	the pipe that the buffer belongs to
  * @buf:	the buffer to attempt to steal
@@ -351,8 +256,6 @@ EXPORT_SYMBOL(generic_pipe_buf_release);
 
 static const struct pipe_buf_operations anon_pipe_buf_ops = {
 	.can_merge = 1,
-	.map = generic_pipe_buf_map,
-	.unmap = generic_pipe_buf_unmap,
 	.confirm = generic_pipe_buf_confirm,
 	.release = anon_pipe_buf_release,
 	.steal = generic_pipe_buf_steal,
@@ -361,8 +264,6 @@ static const struct pipe_buf_operations anon_pipe_buf_ops = {
 
 static const struct pipe_buf_operations packet_pipe_buf_ops = {
 	.can_merge = 0,
-	.map = generic_pipe_buf_map,
-	.unmap = generic_pipe_buf_unmap,
 	.confirm = generic_pipe_buf_confirm,
 	.release = anon_pipe_buf_release,
 	.steal = generic_pipe_buf_steal,
@@ -379,12 +280,15 @@ 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);
@@ -394,9 +298,9 @@ 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;
-			int error, atomic;
+			size_t written;
+			int error;
 
 			if (chars > total_len)
 				chars = total_len;
@@ -408,21 +312,10 @@ pipe_read(struct kiocb *iocb, const struct iovec *_iov,
 				break;
 			}
 
-			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;
-				}
+			written = copy_page_to_iter(buf->page, buf->offset, chars, &iter);
+			if (unlikely(written < chars)) {
 				if (!ret)
-					ret = error;
+					ret = -EFAULT;
 				break;
 			}
 			ret += chars;
@@ -538,10 +431,16 @@ pipe_write(struct kiocb *iocb, const struct iovec *_iov,
 
 			iov_fault_in_pages_read(iov, chars);
 redo1:
-			addr = ops->map(pipe, buf, atomic);
+			if (atomic)
+				addr = kmap_atomic(buf->page);
+			else
+				addr = kmap(buf->page);
 			error = pipe_iov_copy_from_user(offset + addr, iov,
 							chars, atomic);
-			ops->unmap(pipe, buf, addr);
+			if (atomic)
+				kunmap_atomic(addr);
+			else
+				kunmap(buf->page);
 			ret = error;
 			do_wakeup = 1;
 			if (error) {