diff options
Diffstat (limited to 'drivers/s390/net/qeth_core_main.c')
| -rw-r--r-- | drivers/s390/net/qeth_core_main.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c index ffefdd97abca..bae7440abc01 100644 --- a/drivers/s390/net/qeth_core_main.c +++ b/drivers/s390/net/qeth_core_main.c @@ -3890,6 +3890,34 @@ int qeth_hdr_chk_and_bounce(struct sk_buff *skb, struct qeth_hdr **hdr, int len) } EXPORT_SYMBOL_GPL(qeth_hdr_chk_and_bounce); +/** + * qeth_push_hdr() - push a qeth_hdr onto an skb. + * @skb: skb that the qeth_hdr should be pushed onto. + * @hdr: double pointer to a qeth_hdr. When returning with >= 0, + * it contains a valid pointer to a qeth_hdr. + * @len: length of the hdr that needs to be pushed on. + * + * Returns the pushed length. If the header can't be pushed on + * (eg. because it would cross a page boundary), it is allocated from + * the cache instead and 0 is returned. + * Error to create the hdr is indicated by returning with < 0. + */ +int qeth_push_hdr(struct sk_buff *skb, struct qeth_hdr **hdr, unsigned int len) +{ + if (skb_headroom(skb) >= len && + qeth_get_elements_for_range((addr_t)skb->data - len, + (addr_t)skb->data) == 1) { + *hdr = skb_push(skb, len); + return len; + } + /* fall back */ + *hdr = kmem_cache_alloc(qeth_core_header_cache, GFP_ATOMIC); + if (!*hdr) + return -ENOMEM; + return 0; +} +EXPORT_SYMBOL_GPL(qeth_push_hdr); + static void __qeth_fill_buffer(struct sk_buff *skb, struct qeth_qdio_out_buffer *buf, bool is_first_elem, unsigned int offset) |