From 31c7711b509d470ab1e175e7bb98ea66a82aa916 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Sat, 10 Mar 2007 19:04:55 -0300 Subject: [SK_BUFF]: Some more simple skb_reset_network_header conversions This time of the type: skb->nh.iph = (struct iphdr *)skb->data; That is completely equivalent to: skb->nh.raw = skb->data; Wonder why people love casts... :-) Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- net/sctp/input.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/sctp/input.c') diff --git a/net/sctp/input.c b/net/sctp/input.c index 71db66873695..2b0863aba3fb 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -528,7 +528,7 @@ void sctp_v4_err(struct sk_buff *skb, __u32 info) /* Fix up skb to look at the embedded net header. */ saveip = skb->nh.raw; savesctp = skb->h.raw; - skb->nh.iph = iph; + skb_reset_network_header(skb); skb->h.raw = (char *)sh; sk = sctp_err_lookup(AF_INET, skb, sh, &asoc, &transport); /* Put back, the original pointers. */ -- cgit v1.2.3 From eddc9ec53be2ecdbf4efe0efd4a83052594f0ac0 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Fri, 20 Apr 2007 22:47:35 -0700 Subject: [SK_BUFF]: Introduce ip_hdr(), remove skb->nh.iph Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- net/sctp/input.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/sctp/input.c') diff --git a/net/sctp/input.c b/net/sctp/input.c index 2b0863aba3fb..595fe32b3d41 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -154,7 +154,7 @@ int sctp_rcv(struct sk_buff *skb) if (skb->len < sizeof(struct sctp_chunkhdr)) goto discard_it; - family = ipver2af(skb->nh.iph->version); + family = ipver2af(ip_hdr(skb)->version); af = sctp_get_af_specific(family); if (unlikely(!af)) goto discard_it; -- cgit v1.2.3 From ea2ae17d6443abddc79480dc9f7af8feacabddc4 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Wed, 25 Apr 2007 17:55:53 -0700 Subject: [SK_BUFF]: Introduce skb_transport_offset() For the quite common 'skb->h.raw - skb->data' sequence. Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- net/sctp/input.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/sctp/input.c') diff --git a/net/sctp/input.c b/net/sctp/input.c index 595fe32b3d41..9311b5ddf5c0 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -141,7 +141,7 @@ int sctp_rcv(struct sk_buff *skb) sh = (struct sctphdr *) skb->h.raw; /* Pull up the IP and SCTP headers. */ - __skb_pull(skb, skb->h.raw - skb->data); + __skb_pull(skb, skb_transport_offset(skb)); if (skb->len < sizeof(struct sctphdr)) goto discard_it; if ((skb->ip_summed != CHECKSUM_UNNECESSARY) && -- cgit v1.2.3 From 2c0fd387b00a6758550b5ca1aae4408374483fe7 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Tue, 13 Mar 2007 13:59:32 -0300 Subject: [SCTP]: Introduce sctp_hdr() For consistency with all the other skb->h.raw accessors. Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- net/sctp/input.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) (limited to 'net/sctp/input.c') diff --git a/net/sctp/input.c b/net/sctp/input.c index 9311b5ddf5c0..3a322c584c74 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -79,14 +79,10 @@ static void sctp_add_backlog(struct sock *sk, struct sk_buff *skb); /* Calculate the SCTP checksum of an SCTP packet. */ static inline int sctp_rcv_checksum(struct sk_buff *skb) { - struct sctphdr *sh; - __u32 cmp, val; struct sk_buff *list = skb_shinfo(skb)->frag_list; - - sh = (struct sctphdr *) skb->h.raw; - cmp = ntohl(sh->checksum); - - val = sctp_start_cksum((__u8 *)sh, skb_headlen(skb)); + struct sctphdr *sh = sctp_hdr(skb); + __u32 cmp = ntohl(sh->checksum); + __u32 val = sctp_start_cksum((__u8 *)sh, skb_headlen(skb)); for (; list; list = list->next) val = sctp_update_cksum((__u8 *)list->data, skb_headlen(list), @@ -138,7 +134,7 @@ int sctp_rcv(struct sk_buff *skb) if (skb_linearize(skb)) goto discard_it; - sh = (struct sctphdr *) skb->h.raw; + sh = sctp_hdr(skb); /* Pull up the IP and SCTP headers. */ __skb_pull(skb, skb_transport_offset(skb)); @@ -905,7 +901,7 @@ static struct sctp_association *__sctp_rcv_init_lookup(struct sk_buff *skb, struct sctp_association *asoc; union sctp_addr addr; union sctp_addr *paddr = &addr; - struct sctphdr *sh = (struct sctphdr *) skb->h.raw; + struct sctphdr *sh = sctp_hdr(skb); sctp_chunkhdr_t *ch; union sctp_params params; sctp_init_chunk_t *init; -- cgit v1.2.3 From 88c7664f13bd1a36acb8566b93892a4c58759ac6 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Tue, 13 Mar 2007 14:43:18 -0300 Subject: [SK_BUFF]: Introduce icmp_hdr(), remove skb->h.icmph Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- net/sctp/input.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net/sctp/input.c') diff --git a/net/sctp/input.c b/net/sctp/input.c index 3a322c584c74..40d0df80183f 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -507,8 +507,8 @@ void sctp_v4_err(struct sk_buff *skb, __u32 info) { struct iphdr *iph = (struct iphdr *)skb->data; struct sctphdr *sh = (struct sctphdr *)(skb->data + (iph->ihl <<2)); - int type = skb->h.icmph->type; - int code = skb->h.icmph->code; + const int type = icmp_hdr(skb)->type; + const int code = icmp_hdr(skb)->code; struct sock *sk; struct sctp_association *asoc = NULL; struct sctp_transport *transport; -- cgit v1.2.3 From a27ef749e7be3b06fb58df53d94eb97a21f18707 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Tue, 13 Mar 2007 17:17:10 -0300 Subject: [SCTP]: Eliminate some pointer attributions to the skb layer headers Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- net/sctp/input.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'net/sctp/input.c') diff --git a/net/sctp/input.c b/net/sctp/input.c index 40d0df80183f..f38e91b38719 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -506,7 +506,7 @@ void sctp_err_finish(struct sock *sk, struct sctp_association *asoc) void sctp_v4_err(struct sk_buff *skb, __u32 info) { struct iphdr *iph = (struct iphdr *)skb->data; - struct sctphdr *sh = (struct sctphdr *)(skb->data + (iph->ihl <<2)); + const int ihlen = iph->ihl * 4; const int type = icmp_hdr(skb)->type; const int code = icmp_hdr(skb)->code; struct sock *sk; @@ -516,7 +516,7 @@ void sctp_v4_err(struct sk_buff *skb, __u32 info) char *saveip, *savesctp; int err; - if (skb->len < ((iph->ihl << 2) + 8)) { + if (skb->len < ihlen + 8) { ICMP_INC_STATS_BH(ICMP_MIB_INERRORS); return; } @@ -525,8 +525,8 @@ void sctp_v4_err(struct sk_buff *skb, __u32 info) saveip = skb->nh.raw; savesctp = skb->h.raw; skb_reset_network_header(skb); - skb->h.raw = (char *)sh; - sk = sctp_err_lookup(AF_INET, skb, sh, &asoc, &transport); + skb_set_transport_header(skb, ihlen); + sk = sctp_err_lookup(AF_INET, skb, sctp_hdr(skb), &asoc, &transport); /* Put back, the original pointers. */ skb->nh.raw = saveip; skb->h.raw = savesctp; -- cgit v1.2.3 From b0e380b1d8a8e0aca215df97702f99815f05c094 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Tue, 10 Apr 2007 21:21:55 -0700 Subject: [SK_BUFF]: unions of just one member don't get anything done, kill them Renaming skb->h to skb->transport_header, skb->nh to skb->network_header and skb->mac to skb->mac_header, to match the names of the associated helpers (skb[_[re]set]_{transport,network,mac}_header). Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- net/sctp/input.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'net/sctp/input.c') diff --git a/net/sctp/input.c b/net/sctp/input.c index f38e91b38719..87feee166da9 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -522,14 +522,14 @@ void sctp_v4_err(struct sk_buff *skb, __u32 info) } /* Fix up skb to look at the embedded net header. */ - saveip = skb->nh.raw; - savesctp = skb->h.raw; + saveip = skb->network_header; + savesctp = skb->transport_header; skb_reset_network_header(skb); skb_set_transport_header(skb, ihlen); sk = sctp_err_lookup(AF_INET, skb, sctp_hdr(skb), &asoc, &transport); /* Put back, the original pointers. */ - skb->nh.raw = saveip; - skb->h.raw = savesctp; + skb->network_header = saveip; + skb->transport_header = savesctp; if (!sk) { ICMP_INC_STATS_BH(ICMP_MIB_INERRORS); return; -- cgit v1.2.3 From 2e07fa9cd3bac1e28cfe3131ed86b053afb02fc9 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Tue, 10 Apr 2007 21:22:35 -0700 Subject: [SK_BUFF]: Use offsets for skb->{mac,network,transport}_header on 64bit architectures With this we save 8 bytes per network packet, leaving a 4 bytes hole to be used in further shrinking work, likely with the offsetization of other pointers, such as ->{data,tail,end}, at the cost of adds, that were minimized by the usual practice of setting skb->{mac,nh,n}.raw to a local variable that is then accessed multiple times in each function, it also is not more expensive than before with regards to most of the handling of such headers, like setting one of these headers to another (transport to network, etc), or subtracting, adding to/from it, comparing them, etc. Now we have this layout for sk_buff on a x86_64 machine: [acme@mica net-2.6.22]$ pahole vmlinux sk_buff struct sk_buff { struct sk_buff * next; /* 0 8 */ struct sk_buff * prev; /* 8 8 */ struct rb_node rb; /* 16 24 */ struct sock * sk; /* 40 8 */ ktime_t tstamp; /* 48 8 */ struct net_device * dev; /* 56 8 */ /* --- cacheline 1 boundary (64 bytes) --- */ struct net_device * input_dev; /* 64 8 */ sk_buff_data_t transport_header; /* 72 4 */ sk_buff_data_t network_header; /* 76 4 */ sk_buff_data_t mac_header; /* 80 4 */ /* XXX 4 bytes hole, try to pack */ struct dst_entry * dst; /* 88 8 */ struct sec_path * sp; /* 96 8 */ char cb[48]; /* 104 48 */ /* cacheline 2 boundary (128 bytes) was 24 bytes ago*/ unsigned int len; /* 152 4 */ unsigned int data_len; /* 156 4 */ unsigned int mac_len; /* 160 4 */ union { __wsum csum; /* 4 */ __u32 csum_offset; /* 4 */ }; /* 164 4 */ __u32 priority; /* 168 4 */ __u8 local_df:1; /* 172 1 */ __u8 cloned:1; /* 172 1 */ __u8 ip_summed:2; /* 172 1 */ __u8 nohdr:1; /* 172 1 */ __u8 nfctinfo:3; /* 172 1 */ __u8 pkt_type:3; /* 173 1 */ __u8 fclone:2; /* 173 1 */ __u8 ipvs_property:1; /* 173 1 */ /* XXX 2 bits hole, try to pack */ __be16 protocol; /* 174 2 */ void (*destructor)(struct sk_buff *); /* 176 8 */ struct nf_conntrack * nfct; /* 184 8 */ /* --- cacheline 3 boundary (192 bytes) --- */ struct sk_buff * nfct_reasm; /* 192 8 */ struct nf_bridge_info *nf_bridge; /* 200 8 */ __u16 tc_index; /* 208 2 */ __u16 tc_verd; /* 210 2 */ dma_cookie_t dma_cookie; /* 212 4 */ __u32 secmark; /* 216 4 */ __u32 mark; /* 220 4 */ unsigned int truesize; /* 224 4 */ atomic_t users; /* 228 4 */ unsigned char * head; /* 232 8 */ unsigned char * data; /* 240 8 */ unsigned char * tail; /* 248 8 */ /* --- cacheline 4 boundary (256 bytes) --- */ unsigned char * end; /* 256 8 */ }; /* size: 264, cachelines: 5 */ /* sum members: 260, holes: 1, sum holes: 4 */ /* bit holes: 1, sum bit holes: 2 bits */ /* last cacheline: 8 bytes */ On 32 bits nothing changes, and pointers continue to be used with the compiler turning all this abstraction layer into dust. But there are some sk_buff validation tricks that are now possible, humm... :-) Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- net/sctp/input.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net/sctp/input.c') diff --git a/net/sctp/input.c b/net/sctp/input.c index 87feee166da9..1ff47b18724a 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -513,7 +513,7 @@ void sctp_v4_err(struct sk_buff *skb, __u32 info) struct sctp_association *asoc = NULL; struct sctp_transport *transport; struct inet_sock *inet; - char *saveip, *savesctp; + sk_buff_data_t saveip, savesctp; int err; if (skb->len < ihlen + 8) { @@ -527,7 +527,7 @@ void sctp_v4_err(struct sk_buff *skb, __u32 info) skb_reset_network_header(skb); skb_set_transport_header(skb, ihlen); sk = sctp_err_lookup(AF_INET, skb, sctp_hdr(skb), &asoc, &transport); - /* Put back, the original pointers. */ + /* Put back, the original values. */ skb->network_header = saveip; skb->transport_header = savesctp; if (!sk) { -- cgit v1.2.3 From 27a884dc3cb63b93c2b3b643f5b31eed5f8a4d26 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Thu, 19 Apr 2007 20:29:13 -0700 Subject: [SK_BUFF]: Convert skb->tail to sk_buff_data_t So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes on 64bit architectures, allowing us to combine the 4 bytes hole left by the layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4 64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN... :-) Many calculations that previously required that skb->{transport,network, mac}_header be first converted to a pointer now can be done directly, being meaningful as offsets or pointers. Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- net/sctp/input.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net/sctp/input.c') diff --git a/net/sctp/input.c b/net/sctp/input.c index 1ff47b18724a..18b97eedc1fa 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -612,7 +612,7 @@ int sctp_rcv_ootb(struct sk_buff *skb) break; ch_end = ((__u8 *)ch) + WORD_ROUND(ntohs(ch->length)); - if (ch_end > skb->tail) + if (ch_end > skb_tail_pointer(skb)) break; /* RFC 8.4, 2) If the OOTB packet contains an ABORT chunk, the @@ -644,7 +644,7 @@ int sctp_rcv_ootb(struct sk_buff *skb) } ch = (sctp_chunkhdr_t *) ch_end; - } while (ch_end < skb->tail); + } while (ch_end < skb_tail_pointer(skb)); return 0; -- cgit v1.2.3 From 604763722c655c7e3f31ecf6f7b4dafcd26a7a15 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Mon, 9 Apr 2007 11:59:39 -0700 Subject: [NET]: Treat CHECKSUM_PARTIAL as CHECKSUM_UNNECESSARY When a transmitted packet is looped back directly, CHECKSUM_PARTIAL maps to the semantics of CHECKSUM_UNNECESSARY. Therefore we should treat it as such in the stack. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- net/sctp/input.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'net/sctp/input.c') diff --git a/net/sctp/input.c b/net/sctp/input.c index 18b97eedc1fa..885109fb3dda 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -140,8 +140,7 @@ int sctp_rcv(struct sk_buff *skb) __skb_pull(skb, skb_transport_offset(skb)); if (skb->len < sizeof(struct sctphdr)) goto discard_it; - if ((skb->ip_summed != CHECKSUM_UNNECESSARY) && - (sctp_rcv_checksum(skb) < 0)) + if (!skb_csum_unnecessary(skb) && sctp_rcv_checksum(skb) < 0) goto discard_it; skb_pull(skb, sizeof(struct sctphdr)); -- cgit v1.2.3