Commit c81c2d95 authored by Alexander Duyck's avatar Alexander Duyck Committed by David S. Miller

skbuff: remove skb_dma_map/unmap

The two functions skb_dma_map/unmap are unsafe to use as they cause
problems when packets are cloned and sent to multiple devices while a HW
IOMMU is enabled.  Due to this it is best to remove the code so it is not
used by any other network driver maintainters.
Signed-off-by: default avatarAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: default avatarJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent f4188d8a
......@@ -416,14 +416,6 @@ struct sk_buff {
#include <asm/system.h>
#ifdef CONFIG_HAS_DMA
#include <linux/dma-mapping.h>
extern int skb_dma_map(struct device *dev, struct sk_buff *skb,
enum dma_data_direction dir);
extern void skb_dma_unmap(struct device *dev, struct sk_buff *skb,
enum dma_data_direction dir);
#endif
static inline struct dst_entry *skb_dst(const struct sk_buff *skb)
{
return (struct dst_entry *)skb->_skb_dst;
......
......@@ -6,7 +6,6 @@ obj-y := sock.o request_sock.o skbuff.o iovec.o datagram.o stream.o scm.o \
gen_stats.o gen_estimator.o net_namespace.o
obj-$(CONFIG_SYSCTL) += sysctl_net_core.o
obj-$(CONFIG_HAS_DMA) += skb_dma_map.o
obj-y += dev.o ethtool.o dev_mcast.o dst.o netevent.o \
neighbour.o rtnetlink.o utils.o link_watch.o filter.o
......
/* skb_dma_map.c: DMA mapping helpers for socket buffers.
*
* Copyright (C) David S. Miller <davem@davemloft.net>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/dma-mapping.h>
#include <linux/skbuff.h>
int skb_dma_map(struct device *dev, struct sk_buff *skb,
enum dma_data_direction dir)
{
struct skb_shared_info *sp = skb_shinfo(skb);
dma_addr_t map;
int i;
map = dma_map_single(dev, skb->data,
skb_headlen(skb), dir);
if (dma_mapping_error(dev, map))
goto out_err;
sp->dma_head = map;
for (i = 0; i < sp->nr_frags; i++) {
skb_frag_t *fp = &sp->frags[i];
map = dma_map_page(dev, fp->page, fp->page_offset,
fp->size, dir);
if (dma_mapping_error(dev, map))
goto unwind;
sp->dma_maps[i] = map;
}
return 0;
unwind:
while (--i >= 0) {
skb_frag_t *fp = &sp->frags[i];
dma_unmap_page(dev, sp->dma_maps[i],
fp->size, dir);
}
dma_unmap_single(dev, sp->dma_head,
skb_headlen(skb), dir);
out_err:
return -ENOMEM;
}
EXPORT_SYMBOL(skb_dma_map);
void skb_dma_unmap(struct device *dev, struct sk_buff *skb,
enum dma_data_direction dir)
{
struct skb_shared_info *sp = skb_shinfo(skb);
int i;
dma_unmap_single(dev, sp->dma_head,
skb_headlen(skb), dir);
for (i = 0; i < sp->nr_frags; i++) {
skb_frag_t *fp = &sp->frags[i];
dma_unmap_page(dev, sp->dma_maps[i],
fp->size, dir);
}
}
EXPORT_SYMBOL(skb_dma_unmap);
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment