net, xdp: Introduce __xdp_build_skb_from_frame utility routine

Introduce __xdp_build_skb_from_frame utility routine to build
the skb from xdp_frame. Rely on __xdp_build_skb_from_frame in
cpumap code.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/4f9f4c6b3dd3933770c617eb6689dbc0c6e25863.1610475660.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Lorenzo Bianconi 2021-01-12 19:26:12 +01:00 committed by Alexei Starovoitov
parent 09c02d553c
commit 97a0e1ea7b
3 changed files with 49 additions and 44 deletions

View File

@ -164,6 +164,9 @@ void xdp_warn(const char *msg, const char *func, const int line);
#define XDP_WARN(msg) xdp_warn(msg, __func__, __LINE__)
struct xdp_frame *xdp_convert_zc_to_xdp_frame(struct xdp_buff *xdp);
struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf,
struct sk_buff *skb,
struct net_device *dev);
static inline
void xdp_convert_frame_to_buff(struct xdp_frame *frame, struct xdp_buff *xdp)

View File

@ -141,49 +141,6 @@ static void cpu_map_kthread_stop(struct work_struct *work)
kthread_stop(rcpu->kthread);
}
static struct sk_buff *cpu_map_build_skb(struct xdp_frame *xdpf,
struct sk_buff *skb)
{
unsigned int hard_start_headroom;
unsigned int frame_size;
void *pkt_data_start;
/* Part of headroom was reserved to xdpf */
hard_start_headroom = sizeof(struct xdp_frame) + xdpf->headroom;
/* Memory size backing xdp_frame data already have reserved
* room for build_skb to place skb_shared_info in tailroom.
*/
frame_size = xdpf->frame_sz;
pkt_data_start = xdpf->data - hard_start_headroom;
skb = build_skb_around(skb, pkt_data_start, frame_size);
if (unlikely(!skb))
return NULL;
skb_reserve(skb, hard_start_headroom);
__skb_put(skb, xdpf->len);
if (xdpf->metasize)
skb_metadata_set(skb, xdpf->metasize);
/* Essential SKB info: protocol and skb->dev */
skb->protocol = eth_type_trans(skb, xdpf->dev_rx);
/* Optional SKB info, currently missing:
* - HW checksum info (skb->ip_summed)
* - HW RX hash (skb_set_hash)
* - RX ring dev queue index (skb_record_rx_queue)
*/
/* Until page_pool get SKB return path, release DMA here */
xdp_release_frame(xdpf);
/* Allow SKB to reuse area used by xdp_frame */
xdp_scrub_frame(xdpf);
return skb;
}
static void __cpu_map_ring_cleanup(struct ptr_ring *ring)
{
/* The tear-down procedure should have made sure that queue is
@ -350,7 +307,8 @@ static int cpu_map_kthread_run(void *data)
struct sk_buff *skb = skbs[i];
int ret;
skb = cpu_map_build_skb(xdpf, skb);
skb = __xdp_build_skb_from_frame(xdpf, skb,
xdpf->dev_rx);
if (!skb) {
xdp_return_frame(xdpf);
continue;

View File

@ -513,3 +513,47 @@ void xdp_warn(const char *msg, const char *func, const int line)
WARN(1, "XDP_WARN: %s(line:%d): %s\n", func, line, msg);
};
EXPORT_SYMBOL_GPL(xdp_warn);
struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf,
struct sk_buff *skb,
struct net_device *dev)
{
unsigned int headroom, frame_size;
void *hard_start;
/* Part of headroom was reserved to xdpf */
headroom = sizeof(*xdpf) + xdpf->headroom;
/* Memory size backing xdp_frame data already have reserved
* room for build_skb to place skb_shared_info in tailroom.
*/
frame_size = xdpf->frame_sz;
hard_start = xdpf->data - headroom;
skb = build_skb_around(skb, hard_start, frame_size);
if (unlikely(!skb))
return NULL;
skb_reserve(skb, headroom);
__skb_put(skb, xdpf->len);
if (xdpf->metasize)
skb_metadata_set(skb, xdpf->metasize);
/* Essential SKB info: protocol and skb->dev */
skb->protocol = eth_type_trans(skb, dev);
/* Optional SKB info, currently missing:
* - HW checksum info (skb->ip_summed)
* - HW RX hash (skb_set_hash)
* - RX ring dev queue index (skb_record_rx_queue)
*/
/* Until page_pool get SKB return path, release DMA here */
xdp_release_frame(xdpf);
/* Allow SKB to reuse area used by xdp_frame */
xdp_scrub_frame(xdpf);
return skb;
}
EXPORT_SYMBOL_GPL(__xdp_build_skb_from_frame);