[RFC PATCH 10/10] skbuff: remove skb_dma_map/unmap
From: Alexander Duyck <hidden>
Date: 2009-11-25 01:20:58
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
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: Alexander Duyck <redacted> --- include/linux/skbuff.h | 8 ------ net/core/Makefile | 1 - net/core/skb_dma_map.c | 65 ------------------------------------------------ 3 files changed, 0 insertions(+), 74 deletions(-) delete mode 100644 net/core/skb_dma_map.c
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 89eed8c..ae836fd 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h@@ -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;
diff --git a/net/core/Makefile b/net/core/Makefile
index 796f46e..08791ac 100644
--- a/net/core/Makefile
+++ b/net/core/Makefile@@ -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
diff --git a/net/core/skb_dma_map.c b/net/core/skb_dma_map.c
deleted file mode 100644
index 79687df..0000000
--- a/net/core/skb_dma_map.c
+++ /dev/null@@ -1,65 +0,0 @@ -/* 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);