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-rw-r--r--net/core/user_dma.c131
1 files changed, 0 insertions, 131 deletions
diff --git a/net/core/user_dma.c b/net/core/user_dma.c
deleted file mode 100644
index 1b5fefdb8198..000000000000
--- a/net/core/user_dma.c
+++ /dev/null
@@ -1,131 +0,0 @@
-/*
- * Copyright(c) 2004 - 2006 Intel Corporation. All rights reserved.
- * Portions based on net/core/datagram.c and copyrighted by their authors.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the Free
- * Software Foundation; either version 2 of the License, or (at your option)
- * any later version.
- *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program; if not, write to the Free Software Foundation, Inc., 59
- * Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
- * The full GNU General Public License is included in this distribution in the
- * file called COPYING.
- */
-
-/*
- * This code allows the net stack to make use of a DMA engine for
- * skb to iovec copies.
- */
-
-#include <linux/dmaengine.h>
-#include <linux/socket.h>
-#include <linux/export.h>
-#include <net/tcp.h>
-#include <net/netdma.h>
-
-#define NET_DMA_DEFAULT_COPYBREAK 4096
-
-int sysctl_tcp_dma_copybreak = NET_DMA_DEFAULT_COPYBREAK;
-EXPORT_SYMBOL(sysctl_tcp_dma_copybreak);
-
-/**
- * dma_skb_copy_datagram_iovec - Copy a datagram to an iovec.
- * @skb - buffer to copy
- * @offset - offset in the buffer to start copying from
- * @iovec - io vector to copy to
- * @len - amount of data to copy from buffer to iovec
- * @pinned_list - locked iovec buffer data
- *
- * Note: the iovec is modified during the copy.
- */
-int dma_skb_copy_datagram_iovec(struct dma_chan *chan,
- struct sk_buff *skb, int offset, struct iovec *to,
- size_t len, struct dma_pinned_list *pinned_list)
-{
- int start = skb_headlen(skb);
- int i, copy = start - offset;
- struct sk_buff *frag_iter;
- dma_cookie_t cookie = 0;
-
- /* Copy header. */
- if (copy > 0) {
- if (copy > len)
- copy = len;
- cookie = dma_memcpy_to_iovec(chan, to, pinned_list,
- skb->data + offset, copy);
- if (cookie < 0)
- goto fault;
- len -= copy;
- if (len == 0)
- goto end;
- offset += copy;
- }
-
- /* Copy paged appendix. Hmm... why does this look so complicated? */
- for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
- int end;
- const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
-
- WARN_ON(start > offset + len);
-
- end = start + skb_frag_size(frag);
- copy = end - offset;
- if (copy > 0) {
- struct page *page = skb_frag_page(frag);
-
- if (copy > len)
- copy = len;
-
- cookie = dma_memcpy_pg_to_iovec(chan, to, pinned_list, page,
- frag->page_offset + offset - start, copy);
- if (cookie < 0)
- goto fault;
- len -= copy;
- if (len == 0)
- goto end;
- offset += copy;
- }
- start = end;
- }
-
- skb_walk_frags(skb, frag_iter) {
- int end;
-
- WARN_ON(start > offset + len);
-
- end = start + frag_iter->len;
- copy = end - offset;
- if (copy > 0) {
- if (copy > len)
- copy = len;
- cookie = dma_skb_copy_datagram_iovec(chan, frag_iter,
- offset - start,
- to, copy,
- pinned_list);
- if (cookie < 0)
- goto fault;
- len -= copy;
- if (len == 0)
- goto end;
- offset += copy;
- }
- start = end;
- }
-
-end:
- if (!len) {
- skb->dma_cookie = cookie;
- return cookie;
- }
-
-fault:
- return -EFAULT;
-}

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