mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-27 21:45:12 +07:00
c497176cb2
Here the actual receive functions of AF_XDP are implemented, that in a
later commit, will be called from the XDP layers.
There's one set of functions for the XDP_DRV side and another for
XDP_SKB (generic).
A new XDP API, xdp_return_buff, is also introduced.
Adding xdp_return_buff, which is analogous to xdp_return_frame, but
acts upon an struct xdp_buff. The API will be used by AF_XDP in future
commits.
Support for the poll syscall is also implemented.
v2: xskq_validate_id did not update cons_tail.
The entries variable was calculated twice in xskq_nb_avail.
Squashed xdp_return_buff commit.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
133 lines
3.8 KiB
C
133 lines
3.8 KiB
C
/* include/net/xdp.h
|
|
*
|
|
* Copyright (c) 2017 Jesper Dangaard Brouer, Red Hat Inc.
|
|
* Released under terms in GPL version 2. See COPYING.
|
|
*/
|
|
#ifndef __LINUX_NET_XDP_H__
|
|
#define __LINUX_NET_XDP_H__
|
|
|
|
/**
|
|
* DOC: XDP RX-queue information
|
|
*
|
|
* The XDP RX-queue info (xdp_rxq_info) is associated with the driver
|
|
* level RX-ring queues. It is information that is specific to how
|
|
* the driver have configured a given RX-ring queue.
|
|
*
|
|
* Each xdp_buff frame received in the driver carry a (pointer)
|
|
* reference to this xdp_rxq_info structure. This provides the XDP
|
|
* data-path read-access to RX-info for both kernel and bpf-side
|
|
* (limited subset).
|
|
*
|
|
* For now, direct access is only safe while running in NAPI/softirq
|
|
* context. Contents is read-mostly and must not be updated during
|
|
* driver NAPI/softirq poll.
|
|
*
|
|
* The driver usage API is a register and unregister API.
|
|
*
|
|
* The struct is not directly tied to the XDP prog. A new XDP prog
|
|
* can be attached as long as it doesn't change the underlying
|
|
* RX-ring. If the RX-ring does change significantly, the NIC driver
|
|
* naturally need to stop the RX-ring before purging and reallocating
|
|
* memory. In that process the driver MUST call unregistor (which
|
|
* also apply for driver shutdown and unload). The register API is
|
|
* also mandatory during RX-ring setup.
|
|
*/
|
|
|
|
enum xdp_mem_type {
|
|
MEM_TYPE_PAGE_SHARED = 0, /* Split-page refcnt based model */
|
|
MEM_TYPE_PAGE_ORDER0, /* Orig XDP full page model */
|
|
MEM_TYPE_PAGE_POOL,
|
|
MEM_TYPE_MAX,
|
|
};
|
|
|
|
struct xdp_mem_info {
|
|
u32 type; /* enum xdp_mem_type, but known size type */
|
|
u32 id;
|
|
};
|
|
|
|
struct page_pool;
|
|
|
|
struct xdp_rxq_info {
|
|
struct net_device *dev;
|
|
u32 queue_index;
|
|
u32 reg_state;
|
|
struct xdp_mem_info mem;
|
|
} ____cacheline_aligned; /* perf critical, avoid false-sharing */
|
|
|
|
struct xdp_buff {
|
|
void *data;
|
|
void *data_end;
|
|
void *data_meta;
|
|
void *data_hard_start;
|
|
struct xdp_rxq_info *rxq;
|
|
};
|
|
|
|
struct xdp_frame {
|
|
void *data;
|
|
u16 len;
|
|
u16 headroom;
|
|
u16 metasize;
|
|
/* Lifetime of xdp_rxq_info is limited to NAPI/enqueue time,
|
|
* while mem info is valid on remote CPU.
|
|
*/
|
|
struct xdp_mem_info mem;
|
|
struct net_device *dev_rx; /* used by cpumap */
|
|
};
|
|
|
|
/* Convert xdp_buff to xdp_frame */
|
|
static inline
|
|
struct xdp_frame *convert_to_xdp_frame(struct xdp_buff *xdp)
|
|
{
|
|
struct xdp_frame *xdp_frame;
|
|
int metasize;
|
|
int headroom;
|
|
|
|
/* Assure headroom is available for storing info */
|
|
headroom = xdp->data - xdp->data_hard_start;
|
|
metasize = xdp->data - xdp->data_meta;
|
|
metasize = metasize > 0 ? metasize : 0;
|
|
if (unlikely((headroom - metasize) < sizeof(*xdp_frame)))
|
|
return NULL;
|
|
|
|
/* Store info in top of packet */
|
|
xdp_frame = xdp->data_hard_start;
|
|
|
|
xdp_frame->data = xdp->data;
|
|
xdp_frame->len = xdp->data_end - xdp->data;
|
|
xdp_frame->headroom = headroom - sizeof(*xdp_frame);
|
|
xdp_frame->metasize = metasize;
|
|
|
|
/* rxq only valid until napi_schedule ends, convert to xdp_mem_info */
|
|
xdp_frame->mem = xdp->rxq->mem;
|
|
|
|
return xdp_frame;
|
|
}
|
|
|
|
void xdp_return_frame(struct xdp_frame *xdpf);
|
|
void xdp_return_buff(struct xdp_buff *xdp);
|
|
|
|
int xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq,
|
|
struct net_device *dev, u32 queue_index);
|
|
void xdp_rxq_info_unreg(struct xdp_rxq_info *xdp_rxq);
|
|
void xdp_rxq_info_unused(struct xdp_rxq_info *xdp_rxq);
|
|
bool xdp_rxq_info_is_reg(struct xdp_rxq_info *xdp_rxq);
|
|
int xdp_rxq_info_reg_mem_model(struct xdp_rxq_info *xdp_rxq,
|
|
enum xdp_mem_type type, void *allocator);
|
|
|
|
/* Drivers not supporting XDP metadata can use this helper, which
|
|
* rejects any room expansion for metadata as a result.
|
|
*/
|
|
static __always_inline void
|
|
xdp_set_data_meta_invalid(struct xdp_buff *xdp)
|
|
{
|
|
xdp->data_meta = xdp->data + 1;
|
|
}
|
|
|
|
static __always_inline bool
|
|
xdp_data_meta_unsupported(const struct xdp_buff *xdp)
|
|
{
|
|
return unlikely(xdp->data_meta > xdp->data);
|
|
}
|
|
|
|
#endif /* __LINUX_NET_XDP_H__ */
|