diff options
Diffstat (limited to 'net/core/skbuff.c')
| -rw-r--r-- | net/core/skbuff.c | 220 |
1 files changed, 150 insertions, 70 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 3864b4b68fa1..65a74e13c45b 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -354,7 +354,7 @@ EXPORT_SYMBOL(build_skb); struct napi_alloc_cache { struct page_frag_cache page; - size_t skb_count; + unsigned int skb_count; void *skb_cache[NAPI_SKB_CACHE_SIZE]; }; @@ -1962,37 +1962,13 @@ static bool __skb_splice_bits(struct sk_buff *skb, struct pipe_inode_info *pipe, return false; } -ssize_t skb_socket_splice(struct sock *sk, - struct pipe_inode_info *pipe, - struct splice_pipe_desc *spd) -{ - int ret; - - /* Drop the socket lock, otherwise we have reverse - * locking dependencies between sk_lock and i_mutex - * here as compared to sendfile(). We enter here - * with the socket lock held, and splice_to_pipe() will - * grab the pipe inode lock. For sendfile() emulation, - * we call into ->sendpage() with the i_mutex lock held - * and networking will grab the socket lock. - */ - release_sock(sk); - ret = splice_to_pipe(pipe, spd); - lock_sock(sk); - - return ret; -} - /* * Map data from the skb to a pipe. Should handle both the linear part, * the fragments, and the frag list. */ int skb_splice_bits(struct sk_buff *skb, struct sock *sk, unsigned int offset, struct pipe_inode_info *pipe, unsigned int tlen, - unsigned int flags, - ssize_t (*splice_cb)(struct sock *, - struct pipe_inode_info *, - struct splice_pipe_desc *)) + unsigned int flags) { struct partial_page partial[MAX_SKB_FRAGS]; struct page *pages[MAX_SKB_FRAGS]; @@ -2009,7 +1985,7 @@ int skb_splice_bits(struct sk_buff *skb, struct sock *sk, unsigned int offset, __skb_splice_bits(skb, pipe, &offset, &tlen, &spd, sk); if (spd.nr_pages) - ret = splice_cb(sk, pipe, &spd); + ret = splice_to_pipe(pipe, &spd); return ret; } @@ -2445,6 +2421,25 @@ void skb_queue_purge(struct sk_buff_head *list) EXPORT_SYMBOL(skb_queue_purge); /** + * skb_rbtree_purge - empty a skb rbtree + * @root: root of the rbtree to empty + * + * Delete all buffers on an &sk_buff rbtree. Each buffer is removed from + * the list and one reference dropped. This function does not take + * any lock. Synchronization should be handled by the caller (e.g., TCP + * out-of-order queue is protected by the socket lock). + */ +void skb_rbtree_purge(struct rb_root *root) +{ + struct sk_buff *skb, *next; + + rbtree_postorder_for_each_entry_safe(skb, next, root, rbnode) + kfree_skb(skb); + + *root = RB_ROOT; +} + +/** * skb_queue_head - queue a buffer at the list head * @list: list to use * @newsk: buffer to queue @@ -2661,7 +2656,9 @@ int skb_shift(struct sk_buff *tgt, struct sk_buff *skb, int shiftlen) struct skb_frag_struct *fragfrom, *fragto; BUG_ON(shiftlen > skb->len); - BUG_ON(skb_headlen(skb)); /* Would corrupt stream */ + + if (skb_headlen(skb)) + return 0; todo = shiftlen; from = 0; @@ -3078,11 +3075,31 @@ struct sk_buff *skb_segment(struct sk_buff *head_skb, sg = !!(features & NETIF_F_SG); csum = !!can_checksum_protocol(features, proto); - /* GSO partial only requires that we trim off any excess that - * doesn't fit into an MSS sized block, so take care of that - * now. - */ - if (sg && csum && (features & NETIF_F_GSO_PARTIAL)) { + if (sg && csum && (mss != GSO_BY_FRAGS)) { + if (!(features & NETIF_F_GSO_PARTIAL)) { + struct sk_buff *iter; + + if (!list_skb || + !net_gso_ok(features, skb_shinfo(head_skb)->gso_type)) + goto normal; + + /* Split the buffer at the frag_list pointer. + * This is based on the assumption that all + * buffers in the chain excluding the last + * containing the same amount of data. + */ + skb_walk_frags(head_skb, iter) { + if (skb_headlen(iter)) + goto normal; + + len -= iter->len; + } + } + + /* GSO partial only requires that we trim off any excess that + * doesn't fit into an MSS sized block, so take care of that + * now. + */ partial_segs = len / mss; if (partial_segs > 1) mss *= partial_segs; @@ -3090,6 +3107,7 @@ struct sk_buff *skb_segment(struct sk_buff *head_skb, partial_segs = 0; } +normal: headroom = skb_headroom(head_skb); pos = skb_headlen(head_skb); @@ -3281,21 +3299,29 @@ perform_csum_check: */ segs->prev = tail; - /* Update GSO info on first skb in partial sequence. */ if (partial_segs) { + struct sk_buff *iter; int type = skb_shinfo(head_skb)->gso_type; + unsigned short gso_size = skb_shinfo(head_skb)->gso_size; /* Update type to add partial and then remove dodgy if set */ - type |= SKB_GSO_PARTIAL; + type |= (features & NETIF_F_GSO_PARTIAL) / NETIF_F_GSO_PARTIAL * SKB_GSO_PARTIAL; type &= ~SKB_GSO_DODGY; /* Update GSO info and prepare to start updating headers on * our way back down the stack of protocols. */ - skb_shinfo(segs)->gso_size = skb_shinfo(head_skb)->gso_size; - skb_shinfo(segs)->gso_segs = partial_segs; - skb_shinfo(segs)->gso_type = type; - SKB_GSO_CB(segs)->data_offset = skb_headroom(segs) + doffset; + for (iter = segs; iter; iter = iter->next) { + skb_shinfo(iter)->gso_size = gso_size; + skb_shinfo(iter)->gso_segs = partial_segs; + skb_shinfo(iter)->gso_type = type; + SKB_GSO_CB(iter)->data_offset = skb_headroom(iter) + doffset; + } + + if (tail->len - doffset <= gso_size) + skb_shinfo(tail)->gso_size = 0; + else if (tail != segs) + skb_shinfo(tail)->gso_segs = DIV_ROUND_UP(tail->len - doffset, gso_size); } /* Following permits correct backpressure, for protocols @@ -3688,21 +3714,29 @@ int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb) } EXPORT_SYMBOL(sock_queue_err_skb); +static bool is_icmp_err_skb(const struct sk_buff *skb) +{ + return skb && (SKB_EXT_ERR(skb)->ee.ee_origin == SO_EE_ORIGIN_ICMP || + SKB_EXT_ERR(skb)->ee.ee_origin == SO_EE_ORIGIN_ICMP6); +} + struct sk_buff *sock_dequeue_err_skb(struct sock *sk) { struct sk_buff_head *q = &sk->sk_error_queue; - struct sk_buff *skb, *skb_next; + struct sk_buff *skb, *skb_next = NULL; + bool icmp_next = false; unsigned long flags; - int err = 0; spin_lock_irqsave(&q->lock, flags); skb = __skb_dequeue(q); if (skb && (skb_next = skb_peek(q))) - err = SKB_EXT_ERR(skb_next)->ee.ee_errno; + icmp_next = is_icmp_err_skb(skb_next); spin_unlock_irqrestore(&q->lock, flags); - sk->sk_err = err; - if (err) + if (is_icmp_err_skb(skb) && !icmp_next) + sk->sk_err = 0; + + if (skb_next) sk->sk_error_report(sk); return skb; @@ -3814,10 +3848,18 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb, if (!skb_may_tx_timestamp(sk, tsonly)) return; - if (tsonly) - skb = alloc_skb(0, GFP_ATOMIC); - else + if (tsonly) { +#ifdef CONFIG_INET + if ((sk->sk_tsflags & SOF_TIMESTAMPING_OPT_STATS) && + sk->sk_protocol == IPPROTO_TCP && + sk->sk_type == SOCK_STREAM) + skb = tcp_get_timestamping_opt_stats(sk); + else +#endif + skb = alloc_skb(0, GFP_ATOMIC); + } else { skb = skb_clone(orig_skb, GFP_ATOMIC); + } if (!skb) return; @@ -4474,17 +4516,24 @@ int skb_ensure_writable(struct sk_buff *skb, int write_len) } EXPORT_SYMBOL(skb_ensure_writable); -/* remove VLAN header from packet and update csum accordingly. */ -static int __skb_vlan_pop(struct sk_buff *skb, u16 *vlan_tci) +/* remove VLAN header from packet and update csum accordingly. + * expects a non skb_vlan_tag_present skb with a vlan tag payload + */ +int __skb_vlan_pop(struct sk_buff *skb, u16 *vlan_tci) { struct vlan_hdr *vhdr; - unsigned int offset = skb->data - skb_mac_header(skb); + int offset = skb->data - skb_mac_header(skb); int err; - __skb_push(skb, offset); + if (WARN_ONCE(offset, + "__skb_vlan_pop got skb with skb->data not at mac header (offset %d)\n", + offset)) { + return -EINVAL; + } + err = skb_ensure_writable(skb, VLAN_ETH_HLEN); if (unlikely(err)) - goto pull; + return err; skb_postpull_rcsum(skb, skb->data + (2 * ETH_ALEN), VLAN_HLEN); @@ -4501,12 +4550,14 @@ static int __skb_vlan_pop(struct sk_buff *skb, u16 *vlan_tci) skb_set_network_header(skb, ETH_HLEN); skb_reset_mac_len(skb); -pull: - __skb_pull(skb, offset); return err; } +EXPORT_SYMBOL(__skb_vlan_pop); +/* Pop a vlan tag either from hwaccel or from payload. + * Expects skb->data at mac header. + */ int skb_vlan_pop(struct sk_buff *skb) { u16 vlan_tci; @@ -4516,9 +4567,7 @@ int skb_vlan_pop(struct sk_buff *skb) if (likely(skb_vlan_tag_present(skb))) { skb->vlan_tci = 0; } else { - if (unlikely((skb->protocol != htons(ETH_P_8021Q) && - skb->protocol != htons(ETH_P_8021AD)) || - skb->len < VLAN_ETH_HLEN)) + if (unlikely(!eth_type_vlan(skb->protocol))) return 0; err = __skb_vlan_pop(skb, &vlan_tci); @@ -4526,9 +4575,7 @@ int skb_vlan_pop(struct sk_buff *skb) return err; } /* move next vlan tag to hw accel tag */ - if (likely((skb->protocol != htons(ETH_P_8021Q) && - skb->protocol != htons(ETH_P_8021AD)) || - skb->len < VLAN_ETH_HLEN)) + if (likely(!eth_type_vlan(skb->protocol))) return 0; vlan_proto = skb->protocol; @@ -4541,29 +4588,30 @@ int skb_vlan_pop(struct sk_buff *skb) } EXPORT_SYMBOL(skb_vlan_pop); +/* Push a vlan tag either into hwaccel or into payload (if hwaccel tag present). + * Expects skb->data at mac header. + */ int skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci) { if (skb_vlan_tag_present(skb)) { - unsigned int offset = skb->data - skb_mac_header(skb); + int offset = skb->data - skb_mac_header(skb); int err; - /* __vlan_insert_tag expect skb->data pointing to mac header. - * So change skb->data before calling it and change back to - * original position later - */ - __skb_push(skb, offset); + if (WARN_ONCE(offset, + "skb_vlan_push got skb with skb->data not at mac header (offset %d)\n", + offset)) { + return -EINVAL; + } + err = __vlan_insert_tag(skb, skb->vlan_proto, skb_vlan_tag_get(skb)); - if (err) { - __skb_pull(skb, offset); + if (err) return err; - } skb->protocol = skb->vlan_proto; skb->mac_len += VLAN_HLEN; skb_postpush_rcsum(skb, skb->data + (2 * ETH_ALEN), VLAN_HLEN); - __skb_pull(skb, offset); } __vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci); return 0; @@ -4883,3 +4931,35 @@ struct sk_buff *pskb_extract(struct sk_buff *skb, int off, return clone; } EXPORT_SYMBOL(pskb_extract); + +/** + * skb_condense - try to get rid of fragments/frag_list if possible + * @skb: buffer + * + * Can be used to save memory before skb is added to a busy queue. + * If packet has bytes in frags and enough tail room in skb->head, + * pull all of them, so that we can free the frags right now and adjust + * truesize. + * Notes: + * We do not reallocate skb->head thus can not fail. + * Caller must re-evaluate skb->truesize if needed. + */ +void skb_condense(struct sk_buff *skb) +{ + if (skb->data_len) { + if (skb->data_len > skb->end - skb->tail || + skb_cloned(skb)) + return; + + /* Nice, we can free page frag(s) right now */ + __pskb_pull_tail(skb, skb->data_len); + } + /* At this point, skb->truesize might be over estimated, + * because skb had a fragment, and fragments do not tell + * their truesize. + * When we pulled its content into skb->head, fragment + * was freed, but __pskb_pull_tail() could not possibly + * adjust skb->truesize, not knowing the frag truesize. + */ + skb->truesize = SKB_TRUESIZE(skb_end_offset(skb)); +} |
