pipe: kill ->map() and ->unmap()

all pipe_buffer_operations have the same instances of those...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/splice.c b/fs/splice.c
index 12028fa..ca3bfbd 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -136,8 +136,6 @@
 
 const struct pipe_buf_operations page_cache_pipe_buf_ops = {
 	.can_merge = 0,
-	.map = generic_pipe_buf_map,
-	.unmap = generic_pipe_buf_unmap,
 	.confirm = page_cache_pipe_buf_confirm,
 	.release = page_cache_pipe_buf_release,
 	.steal = page_cache_pipe_buf_steal,
@@ -156,8 +154,6 @@
 
 static const struct pipe_buf_operations user_page_pipe_buf_ops = {
 	.can_merge = 0,
-	.map = generic_pipe_buf_map,
-	.unmap = generic_pipe_buf_unmap,
 	.confirm = generic_pipe_buf_confirm,
 	.release = page_cache_pipe_buf_release,
 	.steal = user_page_pipe_buf_steal,
@@ -547,8 +543,6 @@
 
 static const struct pipe_buf_operations default_pipe_buf_ops = {
 	.can_merge = 0,
-	.map = generic_pipe_buf_map,
-	.unmap = generic_pipe_buf_unmap,
 	.confirm = generic_pipe_buf_confirm,
 	.release = generic_pipe_buf_release,
 	.steal = generic_pipe_buf_steal,
@@ -564,8 +558,6 @@
 /* Pipe buffer operations for a socket and similar. */
 const struct pipe_buf_operations nosteal_pipe_buf_ops = {
 	.can_merge = 0,
-	.map = generic_pipe_buf_map,
-	.unmap = generic_pipe_buf_unmap,
 	.confirm = generic_pipe_buf_confirm,
 	.release = generic_pipe_buf_release,
 	.steal = generic_pipe_buf_nosteal,
@@ -767,13 +759,13 @@
 		goto out;
 
 	if (buf->page != page) {
-		char *src = buf->ops->map(pipe, buf, 1);
+		char *src = kmap_atomic(buf->page);
 		char *dst = kmap_atomic(page);
 
 		memcpy(dst + offset, src + buf->offset, this_len);
 		flush_dcache_page(page);
 		kunmap_atomic(dst);
-		buf->ops->unmap(pipe, buf, src);
+		kunmap_atomic(src);
 	}
 	ret = pagecache_write_end(file, mapping, sd->pos, this_len, this_len,
 				page, fsdata);
@@ -1067,9 +1059,9 @@
 	void *data;
 	loff_t tmp = sd->pos;
 
-	data = buf->ops->map(pipe, buf, 0);
+	data = kmap(buf->page);
 	ret = __kernel_write(sd->u.file, data + buf->offset, sd->len, &tmp);
-	buf->ops->unmap(pipe, buf, data);
+	kunmap(buf->page);
 
 	return ret;
 }
@@ -1536,10 +1528,10 @@
 	 * pages and doing an atomic copy
 	 */
 	if (!fault_in_pages_writeable(sd->u.userptr, sd->len)) {
-		src = buf->ops->map(pipe, buf, 1);
+		src = kmap_atomic(buf->page);
 		ret = __copy_to_user_inatomic(sd->u.userptr, src + buf->offset,
 							sd->len);
-		buf->ops->unmap(pipe, buf, src);
+		kunmap_atomic(src);
 		if (!ret) {
 			ret = sd->len;
 			goto out;
@@ -1549,13 +1541,13 @@
 	/*
 	 * No dice, use slow non-atomic map and copy
  	 */
-	src = buf->ops->map(pipe, buf, 0);
+	src = kmap(buf->page);
 
 	ret = sd->len;
 	if (copy_to_user(sd->u.userptr, src + buf->offset, sd->len))
 		ret = -EFAULT;
 
-	buf->ops->unmap(pipe, buf, src);
+	kunmap(buf->page);
 out:
 	if (ret > 0)
 		sd->u.userptr += ret;