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diff -upkr linux-2.6.34/include/linux/mm_types.h linux-2.6.34/include/linux/mm_types.h
--- linux-2.6.34/include/linux/mm_types.h 2010-05-17 01:17:36.000000000 +0400
+++ linux-2.6.34/include/linux/mm_types.h 2010-05-24 14:51:40.000000000 +0400
@@ -100,6 +100,18 @@ struct page {
*/
void *shadow;
#endif
+
+#if defined(CONFIG_TCP_ZERO_COPY_TRANSFER_COMPLETION_NOTIFICATION)
+ /*
+ * Used to implement support for notification on zero-copy TCP transfer
+ * completion. It might look as not good to have this field here and
+ * it's better to have it in struct sk_buff, but it would make the code
+ * much more complicated and fragile, since all skb then would have to
+ * contain only pages with the same value in this field.
+ */
+ void *net_priv;
+#endif
+
};
/*
diff -upkr linux-2.6.34/include/linux/net.h linux-2.6.34/include/linux/net.h
--- linux-2.6.34/include/linux/net.h 2010-05-17 01:17:36.000000000 +0400
+++ linux-2.6.34/include/linux/net.h 2010-05-24 14:51:40.000000000 +0400
@@ -20,6 +20,7 @@
#include <linux/socket.h>
#include <asm/socket.h>
+#include <linux/mm.h>
#define NPROTO AF_MAX
@@ -288,5 +289,44 @@ extern int kernel_sock_shutdown(struct s
extern struct ratelimit_state net_ratelimit_state;
#endif
+#if defined(CONFIG_TCP_ZERO_COPY_TRANSFER_COMPLETION_NOTIFICATION)
+/* Support for notification on zero-copy TCP transfer completion */
+typedef void (*net_get_page_callback_t)(struct page *page);
+typedef void (*net_put_page_callback_t)(struct page *page);
+
+extern net_get_page_callback_t net_get_page_callback;
+extern net_put_page_callback_t net_put_page_callback;
+
+extern int net_set_get_put_page_callbacks(
+ net_get_page_callback_t get_callback,
+ net_put_page_callback_t put_callback);
+
+/*
+ * See comment for net_set_get_put_page_callbacks() why those functions
+ * don't need any protection.
+ */
+static inline void net_get_page(struct page *page)
+{
+ if (page->net_priv != 0)
+ net_get_page_callback(page);
+ get_page(page);
+}
+static inline void net_put_page(struct page *page)
+{
+ if (page->net_priv != 0)
+ net_put_page_callback(page);
+ put_page(page);
+}
+#else
+static inline void net_get_page(struct page *page)
+{
+ get_page(page);
+}
+static inline void net_put_page(struct page *page)
+{
+ put_page(page);
+}
+#endif /* CONFIG_TCP_ZERO_COPY_TRANSFER_COMPLETION_NOTIFICATION */
+
#endif /* __KERNEL__ */
#endif /* _LINUX_NET_H */
diff -upkr linux-2.6.34/net/core/dev.c linux-2.6.34/net/core/dev.c
--- linux-2.6.34/net/core/dev.c 2010-05-17 01:17:36.000000000 +0400
+++ linux-2.6.34/net/core/dev.c 2010-05-24 14:51:40.000000000 +0400
@@ -2732,7 +2732,7 @@ pull:
skb_shinfo(skb)->frags[0].size -= grow;
if (unlikely(!skb_shinfo(skb)->frags[0].size)) {
- put_page(skb_shinfo(skb)->frags[0].page);
+ net_put_page(skb_shinfo(skb)->frags[0].page);
memmove(skb_shinfo(skb)->frags,
skb_shinfo(skb)->frags + 1,
--skb_shinfo(skb)->nr_frags);
diff -upkr linux-2.6.34/net/core/skbuff.c linux-2.6.34/net/core/skbuff.c
--- linux-2.6.34/net/core/skbuff.c 2010-05-17 01:17:36.000000000 +0400
+++ linux-2.6.34/net/core/skbuff.c 2010-05-24 14:51:40.000000000 +0400
@@ -76,13 +76,13 @@ static struct kmem_cache *skbuff_fclone_
static void sock_pipe_buf_release(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
- put_page(buf->page);
+ net_put_page(buf->page);
}
static void sock_pipe_buf_get(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
- get_page(buf->page);
+ net_get_page(buf->page);
}
static int sock_pipe_buf_steal(struct pipe_inode_info *pipe,
@@ -344,7 +344,7 @@ static void skb_release_data(struct sk_b
if (skb_shinfo(skb)->nr_frags) {
int i;
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
- put_page(skb_shinfo(skb)->frags[i].page);
+ net_put_page(skb_shinfo(skb)->frags[i].page);
}
if (skb_has_frags(skb))
@@ -765,7 +765,7 @@ struct sk_buff *pskb_copy(struct sk_buff
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
skb_shinfo(n)->frags[i] = skb_shinfo(skb)->frags[i];
- get_page(skb_shinfo(n)->frags[i].page);
+ net_get_page(skb_shinfo(n)->frags[i].page);
}
skb_shinfo(n)->nr_frags = i;
}
@@ -831,7 +831,7 @@ int pskb_expand_head(struct sk_buff *skb
sizeof(struct skb_shared_info));
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
- get_page(skb_shinfo(skb)->frags[i].page);
+ net_get_page(skb_shinfo(skb)->frags[i].page);
if (skb_has_frags(skb))
skb_clone_fraglist(skb);
@@ -1105,7 +1105,7 @@ drop_pages:
skb_shinfo(skb)->nr_frags = i;
for (; i < nfrags; i++)
- put_page(skb_shinfo(skb)->frags[i].page);
+ net_put_page(skb_shinfo(skb)->frags[i].page);
if (skb_has_frags(skb))
skb_drop_fraglist(skb);
@@ -1274,7 +1274,7 @@ pull_pages:
k = 0;
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
if (skb_shinfo(skb)->frags[i].size <= eat) {
- put_page(skb_shinfo(skb)->frags[i].page);
+ net_put_page(skb_shinfo(skb)->frags[i].page);
eat -= skb_shinfo(skb)->frags[i].size;
} else {
skb_shinfo(skb)->frags[k] = skb_shinfo(skb)->frags[i];
@@ -1375,7 +1375,7 @@ EXPORT_SYMBOL(skb_copy_bits);
*/
static void sock_spd_release(struct splice_pipe_desc *spd, unsigned int i)
{
- put_page(spd->pages[i]);
+ net_put_page(spd->pages[i]);
}
static inline struct page *linear_to_page(struct page *page, unsigned int *len,
@@ -1399,7 +1399,7 @@ new_page:
off = sk->sk_sndmsg_off;
mlen = PAGE_SIZE - off;
if (mlen < 64 && mlen < *len) {
- put_page(p);
+ net_put_page(p);
goto new_page;
}
@@ -1409,7 +1409,7 @@ new_page:
memcpy(page_address(p) + off, page_address(page) + *offset, *len);
sk->sk_sndmsg_off += *len;
*offset = off;
- get_page(p);
+ net_get_page(p);
return p;
}
@@ -1430,7 +1430,7 @@ static inline int spd_fill_page(struct s
if (!page)
return 1;
} else
- get_page(page);
+ net_get_page(page);
spd->pages[spd->nr_pages] = page;
spd->partial[spd->nr_pages].len = *len;
@@ -2060,7 +2060,7 @@ static inline void skb_split_no_header(s
* where splitting is expensive.
* 2. Split is accurately. We make this.
*/
- get_page(skb_shinfo(skb)->frags[i].page);
+ net_get_page(skb_shinfo(skb)->frags[i].page);
skb_shinfo(skb1)->frags[0].page_offset += len - pos;
skb_shinfo(skb1)->frags[0].size -= len - pos;
skb_shinfo(skb)->frags[i].size = len - pos;
@@ -2182,7 +2182,7 @@ int skb_shift(struct sk_buff *tgt, struc
to++;
} else {
- get_page(fragfrom->page);
+ net_get_page(fragfrom->page);
fragto->page = fragfrom->page;
fragto->page_offset = fragfrom->page_offset;
fragto->size = todo;
@@ -2204,7 +2204,7 @@ int skb_shift(struct sk_buff *tgt, struc
fragto = &skb_shinfo(tgt)->frags[merge];
fragto->size += fragfrom->size;
- put_page(fragfrom->page);
+ net_put_page(fragfrom->page);
}
/* Reposition in the original skb */
@@ -2602,7 +2602,7 @@ struct sk_buff *skb_segment(struct sk_bu
while (pos < offset + len && i < nfrags) {
*frag = skb_shinfo(skb)->frags[i];
- get_page(frag->page);
+ net_get_page(frag->page);
size = frag->size;
if (pos < offset) {
diff -upkr linux-2.6.34/net/ipv4/ip_output.c linux-2.6.34/net/ipv4/ip_output.c
--- linux-2.6.34/net/ipv4/ip_output.c 2010-05-17 01:17:36.000000000 +0400
+++ linux-2.6.34/net/ipv4/ip_output.c 2010-05-24 14:51:40.000000000 +0400
@@ -1024,7 +1024,7 @@ alloc_new_skb:
err = -EMSGSIZE;
goto error;
}
- get_page(page);
+ net_get_page(page);
skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0);
frag = &skb_shinfo(skb)->frags[i];
}
@@ -1182,7 +1182,7 @@ ssize_t ip_append_page(struct sock *sk,
if (skb_can_coalesce(skb, i, page, offset)) {
skb_shinfo(skb)->frags[i-1].size += len;
} else if (i < MAX_SKB_FRAGS) {
- get_page(page);
+ net_get_page(page);
skb_fill_page_desc(skb, i, page, offset, len);
} else {
err = -EMSGSIZE;
diff -upkr linux-2.6.34/net/ipv4/Makefile linux-2.6.34/net/ipv4/Makefile
--- linux-2.6.34/net/ipv4/Makefile 2010-05-17 01:17:36.000000000 +0400
+++ linux-2.6.34/net/ipv4/Makefile 2010-05-24 14:51:40.000000000 +0400
@@ -49,6 +49,7 @@ obj-$(CONFIG_TCP_CONG_LP) += tcp_lp.o
obj-$(CONFIG_TCP_CONG_YEAH) += tcp_yeah.o
obj-$(CONFIG_TCP_CONG_ILLINOIS) += tcp_illinois.o
obj-$(CONFIG_NETLABEL) += cipso_ipv4.o
+obj-$(CONFIG_TCP_ZERO_COPY_TRANSFER_COMPLETION_NOTIFICATION) += tcp_zero_copy.o
obj-$(CONFIG_XFRM) += xfrm4_policy.o xfrm4_state.o xfrm4_input.o \
xfrm4_output.o
diff -upkr linux-2.6.34/net/ipv4/tcp.c linux-2.6.34/net/ipv4/tcp.c
--- linux-2.6.34/net/ipv4/tcp.c 2010-05-17 01:17:36.000000000 +0400
+++ linux-2.6.34/net/ipv4/tcp.c 2010-05-24 14:51:40.000000000 +0400
@@ -800,7 +800,7 @@ new_segment:
if (can_coalesce) {
skb_shinfo(skb)->frags[i - 1].size += copy;
} else {
- get_page(page);
+ net_get_page(page);
skb_fill_page_desc(skb, i, page, offset, copy);
}
@@ -1009,7 +1009,7 @@ new_segment:
goto new_segment;
} else if (page) {
if (off == PAGE_SIZE) {
- put_page(page);
+ net_put_page(page);
TCP_PAGE(sk) = page = NULL;
off = 0;
}
@@ -1050,9 +1050,9 @@ new_segment:
} else {
skb_fill_page_desc(skb, i, page, off, copy);
if (TCP_PAGE(sk)) {
- get_page(page);
+ net_get_page(page);
} else if (off + copy < PAGE_SIZE) {
- get_page(page);
+ net_get_page(page);
TCP_PAGE(sk) = page;
}
}
diff -upkr linux-2.6.34/net/ipv4/tcp_output.c linux-2.6.34/net/ipv4/tcp_output.c
--- linux-2.6.34/net/ipv4/tcp_output.c 2010-05-17 01:17:36.000000000 +0400
+++ linux-2.6.34/net/ipv4/tcp_output.c 2010-05-24 14:51:40.000000000 +0400
@@ -1084,7 +1084,7 @@ static void __pskb_trim_head(struct sk_b
k = 0;
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
if (skb_shinfo(skb)->frags[i].size <= eat) {
- put_page(skb_shinfo(skb)->frags[i].page);
+ net_put_page(skb_shinfo(skb)->frags[i].page);
eat -= skb_shinfo(skb)->frags[i].size;
} else {
skb_shinfo(skb)->frags[k] = skb_shinfo(skb)->frags[i];
diff -upkr linux-2.6.34/net/ipv4/tcp_zero_copy.c linux-2.6.34/net/ipv4/tcp_zero_copy.c
--- linux-2.6.34/net/ipv4/tcp_zero_copy.c 2010-03-01 17:30:31.000000000 +0300
+++ linux-2.6.34/net/ipv4/tcp_zero_copy.c 2010-05-24 14:51:40.000000000 +0400
@@ -0,0 +1,49 @@
+/*
+ * Support routines for TCP zero copy transmit
+ *
+ * Created by Vladislav Bolkhovitin
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ */
+
+#include <linux/skbuff.h>
+
+net_get_page_callback_t net_get_page_callback __read_mostly;
+EXPORT_SYMBOL(net_get_page_callback);
+
+net_put_page_callback_t net_put_page_callback __read_mostly;
+EXPORT_SYMBOL(net_put_page_callback);
+
+/*
+ * Caller of this function must ensure that at the moment when it's called
+ * there are no pages in the system with net_priv field set to non-zero
+ * value. Hence, this function, as well as net_get_page() and net_put_page(),
+ * don't need any protection.
+ */
+int net_set_get_put_page_callbacks(
+ net_get_page_callback_t get_callback,
+ net_put_page_callback_t put_callback)
+{
+ int res = 0;
+
+ if ((net_get_page_callback != NULL) && (get_callback != NULL) &&
+ (net_get_page_callback != get_callback)) {
+ res = -EBUSY;
+ goto out;
+ }
+
+ if ((net_put_page_callback != NULL) && (put_callback != NULL) &&
+ (net_put_page_callback != put_callback)) {
+ res = -EBUSY;
+ goto out;
+ }
+
+ net_get_page_callback = get_callback;
+ net_put_page_callback = put_callback;
+
+out:
+ return res;
+}
+EXPORT_SYMBOL(net_set_get_put_page_callbacks);
diff -upkr linux-2.6.34/net/ipv6/ip6_output.c linux-2.6.34/net/ipv6/ip6_output.c
--- linux-2.6.34/net/ipv6/ip6_output.c 2010-05-17 01:17:36.000000000 +0400
+++ linux-2.6.34/net/ipv6/ip6_output.c 2010-05-24 14:51:40.000000000 +0400
@@ -1382,7 +1382,7 @@ alloc_new_skb:
err = -EMSGSIZE;
goto error;
}
- get_page(page);
+ net_get_page(page);
skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0);
frag = &skb_shinfo(skb)->frags[i];
}
diff -upkr linux-2.6.34/net/Kconfig linux-2.6.34/net/Kconfig
--- linux-2.6.34/net/Kconfig 2010-05-17 01:17:36.000000000 +0400
+++ linux-2.6.34/net/Kconfig 2010-05-24 14:51:40.000000000 +0400
@@ -72,6 +72,18 @@ config INET
Short answer: say Y.
+config TCP_ZERO_COPY_TRANSFER_COMPLETION_NOTIFICATION
+ bool "TCP/IP zero-copy transfer completion notification"
+ depends on INET
+ default SCST_ISCSI
+ ---help---
+ Adds support for sending a notification upon completion of a
+ zero-copy TCP/IP transfer. This can speed up certain TCP/IP
+ software. Currently this is only used by the iSCSI target driver
+ iSCSI-SCST.
+
+ If unsure, say N.
+
if INET
source "net/ipv4/Kconfig"
source "net/ipv6/Kconfig"
|
