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-rw-r--r--net/core/skbuff.c220
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));
+}