diff options
| -rw-r--r-- | include/linux/skmsg.h | 9 | ||||
| -rw-r--r-- | net/core/skmsg.c | 20 |
2 files changed, 21 insertions, 8 deletions
diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h index e4b3fb4bb77c..ce7055259877 100644 --- a/include/linux/skmsg.h +++ b/include/linux/skmsg.h @@ -139,6 +139,11 @@ static inline void sk_msg_apply_bytes(struct sk_psock *psock, u32 bytes) } } +static inline u32 sk_msg_iter_dist(u32 start, u32 end) +{ + return end >= start ? end - start : end + (MAX_MSG_FRAGS - start); +} + #define sk_msg_iter_var_prev(var) \ do { \ if (var == 0) \ @@ -198,9 +203,7 @@ static inline u32 sk_msg_elem_used(const struct sk_msg *msg) if (sk_msg_full(msg)) return MAX_MSG_FRAGS; - return msg->sg.end >= msg->sg.start ? - msg->sg.end - msg->sg.start : - msg->sg.end + (MAX_MSG_FRAGS - msg->sg.start); + return sk_msg_iter_dist(msg->sg.start, msg->sg.end); } static inline struct scatterlist *sk_msg_elem(struct sk_msg *msg, int which) diff --git a/net/core/skmsg.c b/net/core/skmsg.c index cf390e0aa73d..ad31e4e53d0a 100644 --- a/net/core/skmsg.c +++ b/net/core/skmsg.c @@ -270,18 +270,28 @@ void sk_msg_trim(struct sock *sk, struct sk_msg *msg, int len) msg->sg.data[i].length -= trim; sk_mem_uncharge(sk, trim); + /* Adjust copybreak if it falls into the trimmed part of last buf */ + if (msg->sg.curr == i && msg->sg.copybreak > msg->sg.data[i].length) + msg->sg.copybreak = msg->sg.data[i].length; out: - /* If we trim data before curr pointer update copybreak and current - * so that any future copy operations start at new copy location. + sk_msg_iter_var_next(i); + msg->sg.end = i; + + /* If we trim data a full sg elem before curr pointer update + * copybreak and current so that any future copy operations + * start at new copy location. * However trimed data that has not yet been used in a copy op * does not require an update. */ - if (msg->sg.curr >= i) { + if (!msg->sg.size) { + msg->sg.curr = msg->sg.start; + msg->sg.copybreak = 0; + } else if (sk_msg_iter_dist(msg->sg.start, msg->sg.curr) >= + sk_msg_iter_dist(msg->sg.start, msg->sg.end)) { + sk_msg_iter_var_prev(i); msg->sg.curr = i; msg->sg.copybreak = msg->sg.data[i].length; } - sk_msg_iter_var_next(i); - msg->sg.end = i; } EXPORT_SYMBOL_GPL(sk_msg_trim); |