![Sjur Braendeland](/assets/img/avatar_default.png)
Previously CAIF supported maximum transfer size of ~4050. The transfer size is now calculated dynamically based on the link layers mtu size. Signed-off-by: Sjur Braendeland@stericsson.com Signed-off-by: David S. Miller <davem@davemloft.net>
580 lines
13 KiB
C
580 lines
13 KiB
C
/*
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* Copyright (C) ST-Ericsson AB 2010
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* Author: Sjur Brendeland/sjur.brandeland@stericsson.com
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* License terms: GNU General Public License (GPL) version 2
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*/
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#include <linux/string.h>
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#include <linux/skbuff.h>
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#include <linux/hardirq.h>
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#include <net/caif/cfpkt.h>
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#define PKT_PREFIX 16
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#define PKT_POSTFIX 2
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#define PKT_LEN_WHEN_EXTENDING 128
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#define PKT_ERROR(pkt, errmsg) do { \
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cfpkt_priv(pkt)->erronous = true; \
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skb_reset_tail_pointer(&pkt->skb); \
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pr_warning("CAIF: " errmsg);\
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} while (0)
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struct cfpktq {
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struct sk_buff_head head;
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atomic_t count;
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/* Lock protects count updates */
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spinlock_t lock;
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};
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/*
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* net/caif/ is generic and does not
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* understand SKB, so we do this typecast
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*/
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struct cfpkt {
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struct sk_buff skb;
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};
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/* Private data inside SKB */
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struct cfpkt_priv_data {
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struct dev_info dev_info;
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bool erronous;
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};
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inline struct cfpkt_priv_data *cfpkt_priv(struct cfpkt *pkt)
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{
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return (struct cfpkt_priv_data *) pkt->skb.cb;
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}
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inline bool is_erronous(struct cfpkt *pkt)
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{
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return cfpkt_priv(pkt)->erronous;
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}
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inline struct sk_buff *pkt_to_skb(struct cfpkt *pkt)
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{
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return &pkt->skb;
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}
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inline struct cfpkt *skb_to_pkt(struct sk_buff *skb)
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{
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return (struct cfpkt *) skb;
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}
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struct cfpkt *cfpkt_fromnative(enum caif_direction dir, void *nativepkt)
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{
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struct cfpkt *pkt = skb_to_pkt(nativepkt);
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cfpkt_priv(pkt)->erronous = false;
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return pkt;
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}
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EXPORT_SYMBOL(cfpkt_fromnative);
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void *cfpkt_tonative(struct cfpkt *pkt)
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{
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return (void *) pkt;
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}
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EXPORT_SYMBOL(cfpkt_tonative);
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static struct cfpkt *cfpkt_create_pfx(u16 len, u16 pfx)
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{
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struct sk_buff *skb;
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if (likely(in_interrupt()))
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skb = alloc_skb(len + pfx, GFP_ATOMIC);
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else
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skb = alloc_skb(len + pfx, GFP_KERNEL);
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if (unlikely(skb == NULL))
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return NULL;
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skb_reserve(skb, pfx);
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return skb_to_pkt(skb);
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}
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inline struct cfpkt *cfpkt_create(u16 len)
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{
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return cfpkt_create_pfx(len + PKT_POSTFIX, PKT_PREFIX);
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}
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EXPORT_SYMBOL(cfpkt_create);
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void cfpkt_destroy(struct cfpkt *pkt)
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{
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struct sk_buff *skb = pkt_to_skb(pkt);
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kfree_skb(skb);
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}
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EXPORT_SYMBOL(cfpkt_destroy);
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inline bool cfpkt_more(struct cfpkt *pkt)
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{
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struct sk_buff *skb = pkt_to_skb(pkt);
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return skb->len > 0;
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}
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EXPORT_SYMBOL(cfpkt_more);
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int cfpkt_peek_head(struct cfpkt *pkt, void *data, u16 len)
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{
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struct sk_buff *skb = pkt_to_skb(pkt);
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if (skb_headlen(skb) >= len) {
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memcpy(data, skb->data, len);
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return 0;
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}
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return !cfpkt_extr_head(pkt, data, len) &&
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!cfpkt_add_head(pkt, data, len);
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}
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EXPORT_SYMBOL(cfpkt_peek_head);
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int cfpkt_extr_head(struct cfpkt *pkt, void *data, u16 len)
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{
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struct sk_buff *skb = pkt_to_skb(pkt);
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u8 *from;
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if (unlikely(is_erronous(pkt)))
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return -EPROTO;
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if (unlikely(len > skb->len)) {
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PKT_ERROR(pkt, "cfpkt_extr_head read beyond end of packet\n");
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return -EPROTO;
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}
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if (unlikely(len > skb_headlen(skb))) {
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if (unlikely(skb_linearize(skb) != 0)) {
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PKT_ERROR(pkt, "cfpkt_extr_head linearize failed\n");
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return -EPROTO;
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}
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}
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from = skb_pull(skb, len);
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from -= len;
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memcpy(data, from, len);
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return 0;
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}
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EXPORT_SYMBOL(cfpkt_extr_head);
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int cfpkt_extr_trail(struct cfpkt *pkt, void *dta, u16 len)
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{
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struct sk_buff *skb = pkt_to_skb(pkt);
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u8 *data = dta;
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u8 *from;
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if (unlikely(is_erronous(pkt)))
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return -EPROTO;
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if (unlikely(skb_linearize(skb) != 0)) {
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PKT_ERROR(pkt, "cfpkt_extr_trail linearize failed\n");
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return -EPROTO;
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}
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if (unlikely(skb->data + len > skb_tail_pointer(skb))) {
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PKT_ERROR(pkt, "cfpkt_extr_trail read beyond end of packet\n");
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return -EPROTO;
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}
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from = skb_tail_pointer(skb) - len;
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skb_trim(skb, skb->len - len);
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memcpy(data, from, len);
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return 0;
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}
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EXPORT_SYMBOL(cfpkt_extr_trail);
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int cfpkt_pad_trail(struct cfpkt *pkt, u16 len)
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{
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return cfpkt_add_body(pkt, NULL, len);
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}
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EXPORT_SYMBOL(cfpkt_pad_trail);
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int cfpkt_add_body(struct cfpkt *pkt, const void *data, u16 len)
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{
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struct sk_buff *skb = pkt_to_skb(pkt);
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struct sk_buff *lastskb;
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u8 *to;
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u16 addlen = 0;
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if (unlikely(is_erronous(pkt)))
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return -EPROTO;
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lastskb = skb;
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/* Check whether we need to add space at the tail */
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if (unlikely(skb_tailroom(skb) < len)) {
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if (likely(len < PKT_LEN_WHEN_EXTENDING))
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addlen = PKT_LEN_WHEN_EXTENDING;
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else
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addlen = len;
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}
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/* Check whether we need to change the SKB before writing to the tail */
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if (unlikely((addlen > 0) || skb_cloned(skb) || skb_shared(skb))) {
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/* Make sure data is writable */
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if (unlikely(skb_cow_data(skb, addlen, &lastskb) < 0)) {
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PKT_ERROR(pkt, "cfpkt_add_body: cow failed\n");
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return -EPROTO;
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}
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/*
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* Is the SKB non-linear after skb_cow_data()? If so, we are
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* going to add data to the last SKB, so we need to adjust
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* lengths of the top SKB.
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*/
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if (lastskb != skb) {
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pr_warning("CAIF: %s(): Packet is non-linear\n",
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__func__);
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skb->len += len;
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skb->data_len += len;
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}
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}
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/* All set to put the last SKB and optionally write data there. */
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to = skb_put(lastskb, len);
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if (likely(data))
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memcpy(to, data, len);
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return 0;
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}
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EXPORT_SYMBOL(cfpkt_add_body);
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inline int cfpkt_addbdy(struct cfpkt *pkt, u8 data)
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{
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return cfpkt_add_body(pkt, &data, 1);
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}
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EXPORT_SYMBOL(cfpkt_addbdy);
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int cfpkt_add_head(struct cfpkt *pkt, const void *data2, u16 len)
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{
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struct sk_buff *skb = pkt_to_skb(pkt);
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struct sk_buff *lastskb;
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u8 *to;
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const u8 *data = data2;
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int ret;
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if (unlikely(is_erronous(pkt)))
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return -EPROTO;
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if (unlikely(skb_headroom(skb) < len)) {
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PKT_ERROR(pkt, "cfpkt_add_head: no headroom\n");
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return -EPROTO;
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}
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/* Make sure data is writable */
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ret = skb_cow_data(skb, 0, &lastskb);
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if (unlikely(ret < 0)) {
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PKT_ERROR(pkt, "cfpkt_add_head: cow failed\n");
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return ret;
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}
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to = skb_push(skb, len);
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memcpy(to, data, len);
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return 0;
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}
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EXPORT_SYMBOL(cfpkt_add_head);
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inline int cfpkt_add_trail(struct cfpkt *pkt, const void *data, u16 len)
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{
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return cfpkt_add_body(pkt, data, len);
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}
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EXPORT_SYMBOL(cfpkt_add_trail);
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inline u16 cfpkt_getlen(struct cfpkt *pkt)
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{
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struct sk_buff *skb = pkt_to_skb(pkt);
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return skb->len;
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}
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EXPORT_SYMBOL(cfpkt_getlen);
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inline u16 cfpkt_iterate(struct cfpkt *pkt,
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u16 (*iter_func)(u16, void *, u16),
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u16 data)
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{
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/*
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* Don't care about the performance hit of linearizing,
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* Checksum should not be used on high-speed interfaces anyway.
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*/
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if (unlikely(is_erronous(pkt)))
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return -EPROTO;
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if (unlikely(skb_linearize(&pkt->skb) != 0)) {
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PKT_ERROR(pkt, "cfpkt_iterate: linearize failed\n");
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return -EPROTO;
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}
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return iter_func(data, pkt->skb.data, cfpkt_getlen(pkt));
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}
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EXPORT_SYMBOL(cfpkt_iterate);
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int cfpkt_setlen(struct cfpkt *pkt, u16 len)
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{
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struct sk_buff *skb = pkt_to_skb(pkt);
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if (unlikely(is_erronous(pkt)))
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return -EPROTO;
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if (likely(len <= skb->len)) {
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if (unlikely(skb->data_len))
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___pskb_trim(skb, len);
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else
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skb_trim(skb, len);
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return cfpkt_getlen(pkt);
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}
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/* Need to expand SKB */
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if (unlikely(!cfpkt_pad_trail(pkt, len - skb->len)))
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PKT_ERROR(pkt, "cfpkt_setlen: skb_pad_trail failed\n");
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return cfpkt_getlen(pkt);
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}
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EXPORT_SYMBOL(cfpkt_setlen);
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struct cfpkt *cfpkt_create_uplink(const unsigned char *data, unsigned int len)
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{
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struct cfpkt *pkt = cfpkt_create_pfx(len + PKT_POSTFIX, PKT_PREFIX);
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if (!pkt)
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return NULL;
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if (unlikely(data != NULL))
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cfpkt_add_body(pkt, data, len);
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return pkt;
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}
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EXPORT_SYMBOL(cfpkt_create_uplink);
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struct cfpkt *cfpkt_append(struct cfpkt *dstpkt,
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struct cfpkt *addpkt,
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u16 expectlen)
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{
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struct sk_buff *dst = pkt_to_skb(dstpkt);
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struct sk_buff *add = pkt_to_skb(addpkt);
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u16 addlen = skb_headlen(add);
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u16 neededtailspace;
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struct sk_buff *tmp;
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u16 dstlen;
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u16 createlen;
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if (unlikely(is_erronous(dstpkt) || is_erronous(addpkt))) {
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return dstpkt;
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}
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if (expectlen > addlen)
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neededtailspace = expectlen;
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else
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neededtailspace = addlen;
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if (dst->tail + neededtailspace > dst->end) {
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/* Create a dumplicate of 'dst' with more tail space */
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struct cfpkt *tmppkt;
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dstlen = skb_headlen(dst);
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createlen = dstlen + neededtailspace;
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tmppkt = cfpkt_create(createlen + PKT_PREFIX + PKT_POSTFIX);
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if (tmppkt == NULL)
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return NULL;
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tmp = pkt_to_skb(tmppkt);
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skb_set_tail_pointer(tmp, dstlen);
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tmp->len = dstlen;
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memcpy(tmp->data, dst->data, dstlen);
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cfpkt_destroy(dstpkt);
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dst = tmp;
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}
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memcpy(skb_tail_pointer(dst), add->data, skb_headlen(add));
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cfpkt_destroy(addpkt);
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dst->tail += addlen;
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dst->len += addlen;
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return skb_to_pkt(dst);
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}
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EXPORT_SYMBOL(cfpkt_append);
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struct cfpkt *cfpkt_split(struct cfpkt *pkt, u16 pos)
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{
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struct sk_buff *skb2;
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struct sk_buff *skb = pkt_to_skb(pkt);
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struct cfpkt *tmppkt;
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u8 *split = skb->data + pos;
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u16 len2nd = skb_tail_pointer(skb) - split;
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if (unlikely(is_erronous(pkt)))
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return NULL;
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if (skb->data + pos > skb_tail_pointer(skb)) {
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PKT_ERROR(pkt,
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"cfpkt_split: trying to split beyond end of packet");
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return NULL;
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}
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/* Create a new packet for the second part of the data */
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tmppkt = cfpkt_create_pfx(len2nd + PKT_PREFIX + PKT_POSTFIX,
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PKT_PREFIX);
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if (tmppkt == NULL)
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return NULL;
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skb2 = pkt_to_skb(tmppkt);
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if (skb2 == NULL)
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return NULL;
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/* Reduce the length of the original packet */
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skb_set_tail_pointer(skb, pos);
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skb->len = pos;
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memcpy(skb2->data, split, len2nd);
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skb2->tail += len2nd;
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skb2->len += len2nd;
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return skb_to_pkt(skb2);
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}
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EXPORT_SYMBOL(cfpkt_split);
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char *cfpkt_log_pkt(struct cfpkt *pkt, char *buf, int buflen)
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{
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struct sk_buff *skb = pkt_to_skb(pkt);
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char *p = buf;
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int i;
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/*
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* Sanity check buffer length, it needs to be at least as large as
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* the header info: ~=50+ bytes
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*/
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if (buflen < 50)
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return NULL;
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snprintf(buf, buflen, "%s: pkt:%p len:%ld(%ld+%ld) {%ld,%ld} data: [",
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is_erronous(pkt) ? "ERRONOUS-SKB" :
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(skb->data_len != 0 ? "COMPLEX-SKB" : "SKB"),
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skb,
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(long) skb->len,
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(long) (skb_tail_pointer(skb) - skb->data),
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(long) skb->data_len,
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(long) (skb->data - skb->head),
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(long) (skb_tail_pointer(skb) - skb->head));
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p = buf + strlen(buf);
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for (i = 0; i < skb_tail_pointer(skb) - skb->data && i < 300; i++) {
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if (p > buf + buflen - 10) {
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sprintf(p, "...");
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p = buf + strlen(buf);
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break;
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}
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sprintf(p, "%02x,", skb->data[i]);
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p = buf + strlen(buf);
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}
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sprintf(p, "]\n");
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return buf;
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}
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EXPORT_SYMBOL(cfpkt_log_pkt);
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int cfpkt_raw_append(struct cfpkt *pkt, void **buf, unsigned int buflen)
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{
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struct sk_buff *skb = pkt_to_skb(pkt);
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struct sk_buff *lastskb;
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caif_assert(buf != NULL);
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if (unlikely(is_erronous(pkt)))
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return -EPROTO;
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/* Make sure SKB is writable */
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if (unlikely(skb_cow_data(skb, 0, &lastskb) < 0)) {
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PKT_ERROR(pkt, "cfpkt_raw_append: skb_cow_data failed\n");
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return -EPROTO;
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}
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if (unlikely(skb_linearize(skb) != 0)) {
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PKT_ERROR(pkt, "cfpkt_raw_append: linearize failed\n");
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return -EPROTO;
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}
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if (unlikely(skb_tailroom(skb) < buflen)) {
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PKT_ERROR(pkt, "cfpkt_raw_append: buffer too short - failed\n");
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return -EPROTO;
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}
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*buf = skb_put(skb, buflen);
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return 1;
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}
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EXPORT_SYMBOL(cfpkt_raw_append);
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int cfpkt_raw_extract(struct cfpkt *pkt, void **buf, unsigned int buflen)
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{
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struct sk_buff *skb = pkt_to_skb(pkt);
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caif_assert(buf != NULL);
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if (unlikely(is_erronous(pkt)))
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return -EPROTO;
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if (unlikely(buflen > skb->len)) {
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PKT_ERROR(pkt, "cfpkt_raw_extract: buflen too large "
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"- failed\n");
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return -EPROTO;
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}
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if (unlikely(buflen > skb_headlen(skb))) {
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if (unlikely(skb_linearize(skb) != 0)) {
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PKT_ERROR(pkt, "cfpkt_raw_extract: linearize failed\n");
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return -EPROTO;
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}
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}
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*buf = skb->data;
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skb_pull(skb, buflen);
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|
return 1;
|
|
}
|
|
EXPORT_SYMBOL(cfpkt_raw_extract);
|
|
|
|
inline bool cfpkt_erroneous(struct cfpkt *pkt)
|
|
{
|
|
return cfpkt_priv(pkt)->erronous;
|
|
}
|
|
EXPORT_SYMBOL(cfpkt_erroneous);
|
|
|
|
struct cfpktq *cfpktq_create(void)
|
|
{
|
|
struct cfpktq *q = kmalloc(sizeof(struct cfpktq), GFP_ATOMIC);
|
|
if (!q)
|
|
return NULL;
|
|
skb_queue_head_init(&q->head);
|
|
atomic_set(&q->count, 0);
|
|
spin_lock_init(&q->lock);
|
|
return q;
|
|
}
|
|
EXPORT_SYMBOL(cfpktq_create);
|
|
|
|
void cfpkt_queue(struct cfpktq *pktq, struct cfpkt *pkt, unsigned short prio)
|
|
{
|
|
atomic_inc(&pktq->count);
|
|
spin_lock(&pktq->lock);
|
|
skb_queue_tail(&pktq->head, pkt_to_skb(pkt));
|
|
spin_unlock(&pktq->lock);
|
|
|
|
}
|
|
EXPORT_SYMBOL(cfpkt_queue);
|
|
|
|
struct cfpkt *cfpkt_qpeek(struct cfpktq *pktq)
|
|
{
|
|
struct cfpkt *tmp;
|
|
spin_lock(&pktq->lock);
|
|
tmp = skb_to_pkt(skb_peek(&pktq->head));
|
|
spin_unlock(&pktq->lock);
|
|
return tmp;
|
|
}
|
|
EXPORT_SYMBOL(cfpkt_qpeek);
|
|
|
|
struct cfpkt *cfpkt_dequeue(struct cfpktq *pktq)
|
|
{
|
|
struct cfpkt *pkt;
|
|
spin_lock(&pktq->lock);
|
|
pkt = skb_to_pkt(skb_dequeue(&pktq->head));
|
|
if (pkt) {
|
|
atomic_dec(&pktq->count);
|
|
caif_assert(atomic_read(&pktq->count) >= 0);
|
|
}
|
|
spin_unlock(&pktq->lock);
|
|
return pkt;
|
|
}
|
|
EXPORT_SYMBOL(cfpkt_dequeue);
|
|
|
|
int cfpkt_qcount(struct cfpktq *pktq)
|
|
{
|
|
return atomic_read(&pktq->count);
|
|
}
|
|
EXPORT_SYMBOL(cfpkt_qcount);
|
|
|
|
struct cfpkt *cfpkt_clone_release(struct cfpkt *pkt)
|
|
{
|
|
struct cfpkt *clone;
|
|
clone = skb_to_pkt(skb_clone(pkt_to_skb(pkt), GFP_ATOMIC));
|
|
/* Free original packet. */
|
|
cfpkt_destroy(pkt);
|
|
if (!clone)
|
|
return NULL;
|
|
return clone;
|
|
}
|
|
EXPORT_SYMBOL(cfpkt_clone_release);
|
|
|
|
struct caif_payload_info *cfpkt_info(struct cfpkt *pkt)
|
|
{
|
|
return (struct caif_payload_info *)&pkt_to_skb(pkt)->cb;
|
|
}
|
|
EXPORT_SYMBOL(cfpkt_info);
|