This patch introduces memory limitation for UDP.
--
Hideo Aoki
Hitachi Computer Products (America) Inc.
Signed-off-by: Satoshi Oshima <[EMAIL PROTECTED]>
Signed-off-by: Hideo Aoki <[EMAIL PROTECTED]>
Documentation/networking/ip-sysctl.txt | 6 ++++
include/net/udp.h | 3 ++
net/ipv4/af_inet.c | 3 ++
net/ipv4/ip_output.c | 47 ++++++++++++++++++++++++++++++---
net/ipv4/sysctl_net_ipv4.c | 11 +++++++
net/ipv4/udp.c | 24 ++++++++++++++++
6 files changed, 91 insertions(+), 3 deletions(-)
diff -pruN linux-2.6.24-rc1-mem003-ipv4-dev-p3/Documentation/networking/ip-sysctl.txt linux-2.6.24-rc1-mem003-ipv4-dev-p4/Documentation/networking/ip-sysctl.txt
--- linux-2.6.24-rc1-mem003-ipv4-dev-p3/Documentation/networking/ip-sysctl.txt 2007-10-24 11:33:58.000000000 -0400
+++ linux-2.6.24-rc1-mem003-ipv4-dev-p4/Documentation/networking/ip-sysctl.txt 2007-10-26 20:35:52.000000000 -0400
@@ -446,6 +446,12 @@ tcp_dma_copybreak - INTEGER
and CONFIG_NET_DMA is enabled.
Default: 4096
+UDP variables:
+
+udp_mem - INTEGER
+ Number of pages allowed for queueing by all UDP sockets.
+ Default is calculated at boot time from amount of available memory.
+
CIPSOv4 Variables:
cipso_cache_enable - BOOLEAN
diff -pruN linux-2.6.24-rc1-mem003-ipv4-dev-p3/include/net/udp.h linux-2.6.24-rc1-mem003-ipv4-dev-p4/include/net/udp.h
--- linux-2.6.24-rc1-mem003-ipv4-dev-p3/include/net/udp.h 2007-10-24 11:47:51.000000000 -0400
+++ linux-2.6.24-rc1-mem003-ipv4-dev-p4/include/net/udp.h 2007-10-26 20:35:52.000000000 -0400
@@ -66,6 +66,7 @@ extern rwlock_t udp_hash_lock;
extern struct proto udp_prot;
extern atomic_t udp_memory_allocated;
+extern int sysctl_udp_mem;
struct sk_buff;
@@ -175,4 +176,6 @@ extern void udp_proc_unregister(struct u
extern int udp4_proc_init(void);
extern void udp4_proc_exit(void);
#endif
+
+extern void udp_init(void);
#endif /* _UDP_H */
diff -pruN linux-2.6.24-rc1-mem003-ipv4-dev-p3/net/ipv4/af_inet.c linux-2.6.24-rc1-mem003-ipv4-dev-p4/net/ipv4/af_inet.c
--- linux-2.6.24-rc1-mem003-ipv4-dev-p3/net/ipv4/af_inet.c 2007-10-24 19:10:27.000000000 -0400
+++ linux-2.6.24-rc1-mem003-ipv4-dev-p4/net/ipv4/af_inet.c 2007-10-26 20:35:52.000000000 -0400
@@ -1446,6 +1446,9 @@ static int __init inet_init(void)
/* Setup TCP slab cache for open requests. */
tcp_init();
+ /* Setup UDP memory threshold */
+ udp_init();
+
/* Add UDP-Lite (RFC 3828) */
udplite4_register();
diff -pruN linux-2.6.24-rc1-mem003-ipv4-dev-p3/net/ipv4/ip_output.c linux-2.6.24-rc1-mem003-ipv4-dev-p4/net/ipv4/ip_output.c
--- linux-2.6.24-rc1-mem003-ipv4-dev-p3/net/ipv4/ip_output.c 2007-10-24 12:31:47.000000000 -0400
+++ linux-2.6.24-rc1-mem003-ipv4-dev-p4/net/ipv4/ip_output.c 2007-10-29 09:36:32.000000000 -0400
@@ -75,6 +75,7 @@
#include <net/icmp.h>
#include <net/checksum.h>
#include <net/inetpeer.h>
+#include <net/udp.h>
#include <linux/igmp.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_bridge.h>
@@ -699,6 +700,20 @@ csum_page(struct page *page, int offset,
return csum;
}
+static inline int __ip_check_max_skb_pages(struct sock *sk, int size)
+{
+ switch(sk->sk_protocol) {
+ case IPPROTO_UDP:
+ if (atomic_read(sk->sk_prot->memory_allocated) + size
+ > sk->sk_prot->sysctl_mem[0])
+ return -ENOBUFS;
+ /* Fall through */
+ default:
+ break;
+ }
+ return 0;
+}
+
static inline int ip_ufo_append_data(struct sock *sk,
int getfrag(void *from, char *to, int offset, int len,
int odd, struct sk_buff *skb),
@@ -707,16 +722,20 @@ static inline int ip_ufo_append_data(str
{
struct sk_buff *skb;
int err;
+ int size = 0;
/* There is support for UDP fragmentation offload by network
* device, so create one single skb packet containing complete
* udp datagram
*/
if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) {
- skb = sock_alloc_send_skb(sk,
- hh_len + fragheaderlen + transhdrlen + 20,
- (flags & MSG_DONTWAIT), &err);
+ size = hh_len + fragheaderlen + transhdrlen + 20;
+ err = __ip_check_max_skb_pages(sk, sk_datagram_pages(size));
+ if (err)
+ return err;
+ skb = sock_alloc_send_skb(sk, size, (flags & MSG_DONTWAIT),
+ &err);
if (skb == NULL)
return err;
@@ -737,6 +756,10 @@ static inline int ip_ufo_append_data(str
sk->sk_sndmsg_off = 0;
}
+ err = __ip_check_max_skb_pages(sk, sk_datagram_pages(size + length -
+ transhdrlen));
+ if (err)
+ goto fail;
err = skb_append_datato_frags(sk,skb, getfrag, from,
(length - transhdrlen));
if (!err) {
@@ -752,6 +775,7 @@ static inline int ip_ufo_append_data(str
/* There is not enough support do UFO ,
* so follow normal path
*/
+fail:
kfree_skb(skb);
return err;
}
@@ -910,6 +934,12 @@ alloc_new_skb:
if (datalen == length + fraggap)
alloclen += rt->u.dst.trailer_len;
+ err = __ip_check_max_skb_pages(sk,
+ sk_datagram_pages(SKB_DATA_ALIGN(alloclen + hh_len + 15)
+ + sizeof(struct sk_buff)));
+ if (err)
+ goto error;
+
if (transhdrlen) {
skb = sock_alloc_send_skb(sk,
alloclen + hh_len + 15,
@@ -1009,6 +1039,11 @@ alloc_new_skb:
frag = &skb_shinfo(skb)->frags[i];
}
} else if (i < MAX_SKB_FRAGS) {
+ err = __ip_check_max_skb_pages(sk,
+ sk_datagram_pages(PAGE_SIZE));
+ if (err)
+ goto error;
+
if (atomic_read(&sk->sk_wmem_alloc) + PAGE_SIZE
> 2 * sk->sk_sndbuf) {
err = -ENOBUFS;
@@ -1126,6 +1161,12 @@ ssize_t ip_append_page(struct sock *sk,
fraggap = skb_prev->len - maxfraglen;
alloclen = fragheaderlen + hh_len + fraggap + 15;
+
+ err = __ip_check_max_skb_pages(sk,
+ sk_datagram_pages(alloclen + sizeof(struct sk_buff)));
+ if (err)
+ goto error;
+
skb = sock_wmalloc(sk, alloclen, 1, sk->sk_allocation);
if (unlikely(!skb)) {
err = -ENOBUFS;
diff -pruN linux-2.6.24-rc1-mem003-ipv4-dev-p3/net/ipv4/sysctl_net_ipv4.c linux-2.6.24-rc1-mem003-ipv4-dev-p4/net/ipv4/sysctl_net_ipv4.c
--- linux-2.6.24-rc1-mem003-ipv4-dev-p3/net/ipv4/sysctl_net_ipv4.c 2007-10-24 11:34:34.000000000 -0400
+++ linux-2.6.24-rc1-mem003-ipv4-dev-p4/net/ipv4/sysctl_net_ipv4.c 2007-10-26 20:35:52.000000000 -0400
@@ -18,6 +18,7 @@
#include <net/ip.h>
#include <net/route.h>
#include <net/tcp.h>
+#include <net/udp.h>
#include <net/cipso_ipv4.h>
#include <net/inet_frag.h>
@@ -885,6 +886,16 @@ ctl_table ipv4_table[] = {
.mode = 0644,
.proc_handler = &proc_dointvec,
},
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "udp_mem",
+ .data = &sysctl_udp_mem,
+ .maxlen = sizeof(sysctl_udp_mem),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec_minmax,
+ .strategy = &sysctl_intvec,
+ .extra1 = &zero
+ },
{ .ctl_name = 0 }
};
diff -pruN linux-2.6.24-rc1-mem003-ipv4-dev-p3/net/ipv4/udp.c linux-2.6.24-rc1-mem003-ipv4-dev-p4/net/ipv4/udp.c
--- linux-2.6.24-rc1-mem003-ipv4-dev-p3/net/ipv4/udp.c 2007-10-26 19:43:20.000000000 -0400
+++ linux-2.6.24-rc1-mem003-ipv4-dev-p4/net/ipv4/udp.c 2007-10-26 20:35:52.000000000 -0400
@@ -82,6 +82,7 @@
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/ioctls.h>
+#include <linux/bootmem.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/module.h>
@@ -115,6 +116,7 @@ struct hlist_head udp_hash[UDP_HTABLE_SI
DEFINE_RWLOCK(udp_hash_lock);
atomic_t udp_memory_allocated;
+int sysctl_udp_mem __read_mostly;
static inline int __udp_lib_lport_inuse(__u16 num,
const struct hlist_head udptable[])
@@ -1023,6 +1025,13 @@ int udp_queue_rcv_skb(struct sock * sk,
goto drop;
}
+ if ((atomic_read(sk->sk_prot->memory_allocated)
+ + sk_datagram_pages(skb->truesize))
+ > sk->sk_prot->sysctl_mem[0]) {
+ UDP_INC_STATS_BH(UDP_MIB_RCVBUFERRORS, up->pcflag);
+ goto drop;
+ }
+
if ((rc = sock_queue_rcv_skb(sk,skb)) < 0) {
/* Note that an ENOMEM error is charged twice */
if (rc == -ENOMEM)
@@ -1458,6 +1467,7 @@ struct proto udp_prot = {
.unhash = udp_lib_unhash,
.get_port = udp_v4_get_port,
.memory_allocated = &udp_memory_allocated,
+ .sysctl_mem = &sysctl_udp_mem,
.obj_size = sizeof(struct udp_sock),
#ifdef CONFIG_COMPAT
.compat_setsockopt = compat_udp_setsockopt,
@@ -1652,6 +1662,20 @@ void udp4_proc_exit(void)
}
#endif /* CONFIG_PROC_FS */
+void __init udp_init(void)
+{
+ unsigned long limit;
+
+ /* Set the pressure threshold up by the same strategy of TCP. It is a
+ * fraction of global memory that is up to 1/2 at 256 MB, decreasing
+ * toward zero with the amount of memory, with a floor of 128 pages.
+ */
+ limit = min(nr_all_pages, 1UL<<(28-PAGE_SHIFT)) >> (20-PAGE_SHIFT);
+ limit = (limit * (nr_all_pages >> (20-PAGE_SHIFT))) >> (PAGE_SHIFT-11);
+ limit = max(limit, 128UL);
+ sysctl_udp_mem = limit / 2 * 3;
+}
+
EXPORT_SYMBOL(udp_disconnect);
EXPORT_SYMBOL(udp_hash);
EXPORT_SYMBOL(udp_hash_lock);
