net: thunderx: Add support for XDP_DROP

Adds support for XDP_DROP.
Also since in XDP mode there is just a single buffer per page,
made changes to recycle DMA mapping info as well along with pages.

Signed-off-by: Sunil Goutham <sgoutham@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Sunil Goutham 2017-05-02 18:36:55 +05:30 committed by David S. Miller
parent 05c773f52b
commit c56d91ce38
3 changed files with 79 additions and 25 deletions

View File

@ -18,6 +18,7 @@
#include <linux/irq.h>
#include <linux/iommu.h>
#include <linux/bpf.h>
#include <linux/bpf_trace.h>
#include <linux/filter.h>
#include "nic_reg.h"
@ -505,6 +506,7 @@ static inline bool nicvf_xdp_rx(struct nicvf *nic,
struct cqe_rx_t *cqe_rx)
{
struct xdp_buff xdp;
struct page *page;
u32 action;
u16 len;
u64 dma_addr, cpu_addr;
@ -527,12 +529,27 @@ static inline bool nicvf_xdp_rx(struct nicvf *nic,
switch (action) {
case XDP_PASS:
case XDP_TX:
case XDP_ABORTED:
case XDP_DROP:
/* Pass on all packets to network stack */
return false;
default:
bpf_warn_invalid_xdp_action(action);
case XDP_ABORTED:
trace_xdp_exception(nic->netdev, prog, action);
case XDP_DROP:
page = virt_to_page(xdp.data);
/* Check if it's a recycled page, if not
* unmap the DMA mapping.
*
* Recycled page holds an extra reference.
*/
if (page_ref_count(page) == 1) {
dma_addr &= PAGE_MASK;
dma_unmap_page_attrs(&nic->pdev->dev, dma_addr,
RCV_FRAG_LEN, DMA_FROM_DEVICE,
DMA_ATTR_SKIP_CPU_SYNC);
}
put_page(page);
return true;
}
return false;
}
@ -645,7 +662,7 @@ static void nicvf_rcv_pkt_handler(struct net_device *netdev,
if (nicvf_xdp_rx(snic, nic->xdp_prog, cqe_rx))
return;
skb = nicvf_get_rcv_skb(snic, cqe_rx);
skb = nicvf_get_rcv_skb(snic, cqe_rx, nic->xdp_prog ? true : false);
if (!skb) {
netdev_dbg(nic->netdev, "Packet not received\n");
return;

View File

@ -117,6 +117,7 @@ static struct pgcache *nicvf_alloc_page(struct nicvf *nic,
/* Save the page in page cache */
pgcache->page = page;
pgcache->dma_addr = 0;
rbdr->pgalloc++;
}
@ -144,7 +145,7 @@ static inline int nicvf_alloc_rcv_buffer(struct nicvf *nic, struct rbdr *rbdr,
/* Check if request can be accomodated in previous allocated page.
* But in XDP mode only one buffer per page is permitted.
*/
if (!nic->pnicvf->xdp_prog && nic->rb_page &&
if (!rbdr->is_xdp && nic->rb_page &&
((nic->rb_page_offset + buf_len) <= PAGE_SIZE)) {
nic->rb_pageref++;
goto ret;
@ -165,6 +166,9 @@ static inline int nicvf_alloc_rcv_buffer(struct nicvf *nic, struct rbdr *rbdr,
if (pgcache)
nic->rb_page = pgcache->page;
ret:
if (rbdr->is_xdp && pgcache && pgcache->dma_addr) {
*rbuf = pgcache->dma_addr;
} else {
/* HW will ensure data coherency, CPU sync not required */
*rbuf = (u64)dma_map_page_attrs(&nic->pdev->dev, nic->rb_page,
nic->rb_page_offset, buf_len,
@ -176,7 +180,10 @@ ret:
nic->rb_page = NULL;
return -ENOMEM;
}
if (pgcache)
pgcache->dma_addr = *rbuf;
nic->rb_page_offset += buf_len;
}
return 0;
}
@ -230,8 +237,16 @@ static int nicvf_init_rbdr(struct nicvf *nic, struct rbdr *rbdr,
* On embedded platforms i.e 81xx/83xx available memory itself
* is low and minimum ring size of RBDR is 8K, that takes away
* lots of memory.
*
* But for XDP it has to be a single buffer per page.
*/
if (!nic->pnicvf->xdp_prog) {
rbdr->pgcnt = ring_len / (PAGE_SIZE / buf_size);
rbdr->is_xdp = false;
} else {
rbdr->pgcnt = ring_len;
rbdr->is_xdp = true;
}
rbdr->pgcnt = roundup_pow_of_two(rbdr->pgcnt);
rbdr->pgcache = kzalloc(sizeof(*rbdr->pgcache) *
rbdr->pgcnt, GFP_KERNEL);
@ -1454,8 +1469,31 @@ static inline unsigned frag_num(unsigned i)
#endif
}
static void nicvf_unmap_rcv_buffer(struct nicvf *nic, u64 dma_addr,
u64 buf_addr, bool xdp)
{
struct page *page = NULL;
int len = RCV_FRAG_LEN;
if (xdp) {
page = virt_to_page(phys_to_virt(buf_addr));
/* Check if it's a recycled page, if not
* unmap the DMA mapping.
*
* Recycled page holds an extra reference.
*/
if (page_ref_count(page) != 1)
return;
/* Receive buffers in XDP mode are mapped from page start */
dma_addr &= PAGE_MASK;
}
dma_unmap_page_attrs(&nic->pdev->dev, dma_addr, len,
DMA_FROM_DEVICE, DMA_ATTR_SKIP_CPU_SYNC);
}
/* Returns SKB for a received packet */
struct sk_buff *nicvf_get_rcv_skb(struct nicvf *nic, struct cqe_rx_t *cqe_rx)
struct sk_buff *nicvf_get_rcv_skb(struct nicvf *nic,
struct cqe_rx_t *cqe_rx, bool xdp)
{
int frag;
int payload_len = 0;
@ -1490,10 +1528,9 @@ struct sk_buff *nicvf_get_rcv_skb(struct nicvf *nic, struct cqe_rx_t *cqe_rx)
if (!frag) {
/* First fragment */
dma_unmap_page_attrs(&nic->pdev->dev,
nicvf_unmap_rcv_buffer(nic,
*rb_ptrs - cqe_rx->align_pad,
RCV_FRAG_LEN, DMA_FROM_DEVICE,
DMA_ATTR_SKIP_CPU_SYNC);
phys_addr, xdp);
skb = nicvf_rb_ptr_to_skb(nic,
phys_addr - cqe_rx->align_pad,
payload_len);
@ -1503,9 +1540,7 @@ struct sk_buff *nicvf_get_rcv_skb(struct nicvf *nic, struct cqe_rx_t *cqe_rx)
skb_put(skb, payload_len);
} else {
/* Add fragments */
dma_unmap_page_attrs(&nic->pdev->dev, *rb_ptrs,
RCV_FRAG_LEN, DMA_FROM_DEVICE,
DMA_ATTR_SKIP_CPU_SYNC);
nicvf_unmap_rcv_buffer(nic, *rb_ptrs, phys_addr, xdp);
page = virt_to_page(phys_to_virt(phys_addr));
offset = phys_to_virt(phys_addr) - page_address(page);
skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page,

View File

@ -228,6 +228,7 @@ struct rbdr {
u32 head;
u32 tail;
struct q_desc_mem dmem;
bool is_xdp;
/* For page recycling */
int pgidx;
@ -339,7 +340,8 @@ void nicvf_sq_free_used_descs(struct net_device *netdev,
int nicvf_sq_append_skb(struct nicvf *nic, struct snd_queue *sq,
struct sk_buff *skb, u8 sq_num);
struct sk_buff *nicvf_get_rcv_skb(struct nicvf *nic, struct cqe_rx_t *cqe_rx);
struct sk_buff *nicvf_get_rcv_skb(struct nicvf *nic,
struct cqe_rx_t *cqe_rx, bool xdp);
void nicvf_rbdr_task(unsigned long data);
void nicvf_rbdr_work(struct work_struct *work);