/* SPDX-License-Identifier: GPL-2.0-only */ /* Copyright (C) 2025 Intel Corporation */ #ifndef __LIBETH_XDP_H #define __LIBETH_XDP_H #include #include #include #include #include /* * Defined as bits to be able to use them as a mask on Rx. * Also used as internal return values on Tx. */ enum { LIBETH_XDP_PASS = 0U, LIBETH_XDP_DROP = BIT(0), LIBETH_XDP_ABORTED = BIT(1), LIBETH_XDP_TX = BIT(2), LIBETH_XDP_REDIRECT = BIT(3), }; /* * &xdp_buff_xsk is the largest structure &libeth_xdp_buff gets casted to, * pick maximum pointer-compatible alignment. */ #define __LIBETH_XDP_BUFF_ALIGN \ (IS_ALIGNED(sizeof(struct xdp_buff_xsk), 16) ? 16 : \ IS_ALIGNED(sizeof(struct xdp_buff_xsk), 8) ? 8 : \ sizeof(long)) /** * struct libeth_xdp_buff - libeth extension over &xdp_buff * @base: main &xdp_buff * @data: shortcut for @base.data * @desc: RQ descriptor containing metadata for this buffer * @priv: driver-private scratchspace * * The main reason for this is to have a pointer to the descriptor to be able * to quickly get frame metadata from xdpmo and driver buff-to-xdp callbacks * (as well as bigger alignment). * Pointer/layout-compatible with &xdp_buff and &xdp_buff_xsk. */ struct libeth_xdp_buff { union { struct xdp_buff base; void *data; }; const void *desc; unsigned long priv[] __aligned(__LIBETH_XDP_BUFF_ALIGN); } __aligned(__LIBETH_XDP_BUFF_ALIGN); static_assert(offsetof(struct libeth_xdp_buff, data) == offsetof(struct xdp_buff_xsk, xdp.data)); static_assert(offsetof(struct libeth_xdp_buff, desc) == offsetof(struct xdp_buff_xsk, cb)); static_assert(IS_ALIGNED(sizeof(struct xdp_buff_xsk), __alignof(struct libeth_xdp_buff))); /** * __LIBETH_XDP_ONSTACK_BUFF - declare a &libeth_xdp_buff on the stack * @name: name of the variable to declare * @...: sizeof() of the driver-private data */ #define __LIBETH_XDP_ONSTACK_BUFF(name, ...) \ ___LIBETH_XDP_ONSTACK_BUFF(name, ##__VA_ARGS__) /** * LIBETH_XDP_ONSTACK_BUFF - declare a &libeth_xdp_buff on the stack * @name: name of the variable to declare * @...: type or variable name of the driver-private data */ #define LIBETH_XDP_ONSTACK_BUFF(name, ...) \ __LIBETH_XDP_ONSTACK_BUFF(name, __libeth_xdp_priv_sz(__VA_ARGS__)) #define ___LIBETH_XDP_ONSTACK_BUFF(name, ...) \ __DEFINE_FLEX(struct libeth_xdp_buff, name, priv, \ LIBETH_XDP_PRIV_SZ(__VA_ARGS__ + 0), \ __uninitialized); \ LIBETH_XDP_ASSERT_PRIV_SZ(__VA_ARGS__ + 0) #define __libeth_xdp_priv_sz(...) \ CONCATENATE(__libeth_xdp_psz, COUNT_ARGS(__VA_ARGS__))(__VA_ARGS__) #define __libeth_xdp_psz0(...) #define __libeth_xdp_psz1(...) sizeof(__VA_ARGS__) #define LIBETH_XDP_PRIV_SZ(sz) \ (ALIGN(sz, __alignof(struct libeth_xdp_buff)) / sizeof(long)) /* Performs XSK_CHECK_PRIV_TYPE() */ #define LIBETH_XDP_ASSERT_PRIV_SZ(sz) \ static_assert(offsetofend(struct xdp_buff_xsk, cb) >= \ struct_size_t(struct libeth_xdp_buff, priv, \ LIBETH_XDP_PRIV_SZ(sz))) /* XDPSQ sharing */ DECLARE_STATIC_KEY_FALSE(libeth_xdpsq_share); /** * libeth_xdpsq_num - calculate optimal number of XDPSQs for this device + sys * @rxq: current number of active Rx queues * @txq: current number of active Tx queues * @max: maximum number of Tx queues * * Each RQ must have its own XDPSQ for XSk pairs, each CPU must have own XDPSQ * for lockless sending (``XDP_TX``, .ndo_xdp_xmit()). Cap the maximum of these * two with the number of SQs the device can have (minus used ones). * * Return: number of XDP Tx queues the device needs to use. */ static inline u32 libeth_xdpsq_num(u32 rxq, u32 txq, u32 max) { return min(max(nr_cpu_ids, rxq), max - txq); } /** * libeth_xdpsq_shared - whether XDPSQs can be shared between several CPUs * @num: number of active XDPSQs * * Return: true if there's no 1:1 XDPSQ/CPU association, false otherwise. */ static inline bool libeth_xdpsq_shared(u32 num) { return num < nr_cpu_ids; } /** * libeth_xdpsq_id - get XDPSQ index corresponding to this CPU * @num: number of active XDPSQs * * Helper for libeth_xdp routines, do not use in drivers directly. * * Return: XDPSQ index needs to be used on this CPU. */ static inline u32 libeth_xdpsq_id(u32 num) { u32 ret = raw_smp_processor_id(); if (static_branch_unlikely(&libeth_xdpsq_share) && libeth_xdpsq_shared(num)) ret %= num; return ret; } void __libeth_xdpsq_get(struct libeth_xdpsq_lock *lock, const struct net_device *dev); void __libeth_xdpsq_put(struct libeth_xdpsq_lock *lock, const struct net_device *dev); /** * libeth_xdpsq_get - initialize &libeth_xdpsq_lock * @lock: lock to initialize * @dev: netdev which this lock belongs to * @share: whether XDPSQs can be shared * * Tracks the current XDPSQ association and enables the static lock * if needed. */ static inline void libeth_xdpsq_get(struct libeth_xdpsq_lock *lock, const struct net_device *dev, bool share) { if (unlikely(share)) __libeth_xdpsq_get(lock, dev); } /** * libeth_xdpsq_put - deinitialize &libeth_xdpsq_lock * @lock: lock to deinitialize * @dev: netdev which this lock belongs to * * Tracks the current XDPSQ association and disables the static lock * if needed. */ static inline void libeth_xdpsq_put(struct libeth_xdpsq_lock *lock, const struct net_device *dev) { if (static_branch_unlikely(&libeth_xdpsq_share) && lock->share) __libeth_xdpsq_put(lock, dev); } void __libeth_xdpsq_lock(struct libeth_xdpsq_lock *lock); void __libeth_xdpsq_unlock(struct libeth_xdpsq_lock *lock); /** * libeth_xdpsq_lock - grab &libeth_xdpsq_lock if needed * @lock: lock to take * * Touches the underlying spinlock only if the static key is enabled * and the queue itself is marked as shareable. */ static inline void libeth_xdpsq_lock(struct libeth_xdpsq_lock *lock) { if (static_branch_unlikely(&libeth_xdpsq_share) && lock->share) __libeth_xdpsq_lock(lock); } /** * libeth_xdpsq_unlock - free &libeth_xdpsq_lock if needed * @lock: lock to free * * Touches the underlying spinlock only if the static key is enabled * and the queue itself is marked as shareable. */ static inline void libeth_xdpsq_unlock(struct libeth_xdpsq_lock *lock) { if (static_branch_unlikely(&libeth_xdpsq_share) && lock->share) __libeth_xdpsq_unlock(lock); } /* XDPSQ clean-up timers */ void libeth_xdpsq_init_timer(struct libeth_xdpsq_timer *timer, void *xdpsq, struct libeth_xdpsq_lock *lock, void (*poll)(struct work_struct *work)); /** * libeth_xdpsq_deinit_timer - deinitialize &libeth_xdpsq_timer * @timer: timer to deinitialize * * Flush and disable the underlying workqueue. */ static inline void libeth_xdpsq_deinit_timer(struct libeth_xdpsq_timer *timer) { cancel_delayed_work_sync(&timer->dwork); } /** * libeth_xdpsq_queue_timer - run &libeth_xdpsq_timer * @timer: timer to queue * * Should be called after the queue was filled and the transmission was run * to complete the pending buffers if no further sending will be done in a * second (-> lazy cleaning won't happen). * If the timer was already run, it will be requeued back to one second * timeout again. */ static inline void libeth_xdpsq_queue_timer(struct libeth_xdpsq_timer *timer) { mod_delayed_work_on(raw_smp_processor_id(), system_bh_highpri_wq, &timer->dwork, HZ); } /** * libeth_xdpsq_run_timer - wrapper to run a queue clean-up on a timer event * @work: workqueue belonging to the corresponding timer * @poll: driver-specific completion queue poll function * * Run the polling function on the locked queue and requeue the timer if * there's more work to do. * Designed to be used via LIBETH_XDP_DEFINE_TIMER() below. */ static __always_inline void libeth_xdpsq_run_timer(struct work_struct *work, u32 (*poll)(void *xdpsq, u32 budget)) { struct libeth_xdpsq_timer *timer = container_of(work, typeof(*timer), dwork.work); libeth_xdpsq_lock(timer->lock); if (poll(timer->xdpsq, U32_MAX)) libeth_xdpsq_queue_timer(timer); libeth_xdpsq_unlock(timer->lock); } /* Common Tx bits */ /** * enum - libeth_xdp internal Tx flags * @LIBETH_XDP_TX_BULK: one bulk size at which it will be flushed to the queue * @LIBETH_XDP_TX_BATCH: batch size for which the queue fill loop is unrolled * @LIBETH_XDP_TX_DROP: indicates the send function must drop frames not sent * @LIBETH_XDP_TX_NDO: whether the send function is called from .ndo_xdp_xmit() * @LIBETH_XDP_TX_XSK: whether the function is called for ``XDP_TX`` for XSk */ enum { LIBETH_XDP_TX_BULK = DEV_MAP_BULK_SIZE, LIBETH_XDP_TX_BATCH = 8, LIBETH_XDP_TX_DROP = BIT(0), LIBETH_XDP_TX_NDO = BIT(1), LIBETH_XDP_TX_XSK = BIT(2), }; /** * enum - &libeth_xdp_tx_frame and &libeth_xdp_tx_desc flags * @LIBETH_XDP_TX_LEN: only for ``XDP_TX``, [15:0] of ::len_fl is actual length * @LIBETH_XDP_TX_CSUM: for XSk xmit, enable checksum offload * @LIBETH_XDP_TX_XSKMD: for XSk xmit, mask of the metadata bits * @LIBETH_XDP_TX_FIRST: indicates the frag is the first one of the frame * @LIBETH_XDP_TX_LAST: whether the frag is the last one of the frame * @LIBETH_XDP_TX_MULTI: whether the frame contains several frags * @LIBETH_XDP_TX_FLAGS: only for ``XDP_TX``, [31:16] of ::len_fl is flags */ enum { LIBETH_XDP_TX_LEN = GENMASK(15, 0), LIBETH_XDP_TX_CSUM = XDP_TXMD_FLAGS_CHECKSUM, LIBETH_XDP_TX_XSKMD = LIBETH_XDP_TX_LEN, LIBETH_XDP_TX_FIRST = BIT(16), LIBETH_XDP_TX_LAST = BIT(17), LIBETH_XDP_TX_MULTI = BIT(18), LIBETH_XDP_TX_FLAGS = GENMASK(31, 16), }; /** * struct libeth_xdp_tx_frame - represents one XDP Tx element * @data: frame start pointer for ``XDP_TX`` * @len_fl: ``XDP_TX``, combined flags [31:16] and len [15:0] field for speed * @soff: ``XDP_TX``, offset from @data to the start of &skb_shared_info * @frag: one (non-head) frag for ``XDP_TX`` * @xdpf: &xdp_frame for the head frag for .ndo_xdp_xmit() * @dma: DMA address of the non-head frag for .ndo_xdp_xmit() * @xsk: ``XDP_TX`` for XSk, XDP buffer for any frag * @len: frag length for XSk ``XDP_TX`` and .ndo_xdp_xmit() * @flags: Tx flags for the above * @opts: combined @len + @flags for the above for speed * @desc: XSk xmit descriptor for direct casting */ struct libeth_xdp_tx_frame { union { /* ``XDP_TX`` */ struct { void *data; u32 len_fl; u32 soff; }; /* ``XDP_TX`` frag */ skb_frag_t frag; /* .ndo_xdp_xmit(), XSk ``XDP_TX`` */ struct { union { struct xdp_frame *xdpf; dma_addr_t dma; struct libeth_xdp_buff *xsk; }; union { struct { u32 len; u32 flags; }; aligned_u64 opts; }; }; /* XSk xmit */ struct xdp_desc desc; }; } __aligned(sizeof(struct xdp_desc)); static_assert(offsetof(struct libeth_xdp_tx_frame, frag.len) == offsetof(struct libeth_xdp_tx_frame, len_fl)); static_assert(sizeof(struct libeth_xdp_tx_frame) == sizeof(struct xdp_desc)); /** * struct libeth_xdp_tx_bulk - XDP Tx frame bulk for bulk sending * @prog: corresponding active XDP program, %NULL for .ndo_xdp_xmit() * @dev: &net_device which the frames are transmitted on * @xdpsq: shortcut to the corresponding driver-specific XDPSQ structure * @act_mask: Rx only, mask of all the XDP prog verdicts for that NAPI session * @count: current number of frames in @bulk * @bulk: array of queued frames for bulk Tx * * All XDP Tx operations except XSk xmit queue each frame to the bulk first * and flush it when @count reaches the array end. Bulk is always placed on * the stack for performance. One bulk element contains all the data necessary * for sending a frame and then freeing it on completion. * For XSk xmit, Tx descriptor array from &xsk_buff_pool is casted directly * to &libeth_xdp_tx_frame as they are compatible and the bulk structure is * not used. */ struct libeth_xdp_tx_bulk { const struct bpf_prog *prog; struct net_device *dev; void *xdpsq; u32 act_mask; u32 count; struct libeth_xdp_tx_frame bulk[LIBETH_XDP_TX_BULK]; } __aligned(sizeof(struct libeth_xdp_tx_frame)); /** * LIBETH_XDP_ONSTACK_BULK - declare &libeth_xdp_tx_bulk on the stack * @bq: name of the variable to declare * * Helper to declare a bulk on the stack with a compiler hint that it should * not be initialized automatically (with `CONFIG_INIT_STACK_ALL_*`) for * performance reasons. */ #define LIBETH_XDP_ONSTACK_BULK(bq) \ struct libeth_xdp_tx_bulk bq __uninitialized /** * struct libeth_xdpsq - abstraction for an XDPSQ * @pool: XSk buffer pool for XSk ``XDP_TX`` and xmit * @sqes: array of Tx buffers from the actual queue struct * @descs: opaque pointer to the HW descriptor array * @ntu: pointer to the next free descriptor index * @count: number of descriptors on that queue * @pending: pointer to the number of sent-not-completed descs on that queue * @xdp_tx: pointer to the above, but only for non-XSk-xmit frames * @lock: corresponding XDPSQ lock * * Abstraction for driver-independent implementation of Tx. Placed on the stack * and filled by the driver before the transmission, so that the generic * functions can access and modify driver-specific resources. */ struct libeth_xdpsq { struct xsk_buff_pool *pool; struct libeth_sqe *sqes; void *descs; u32 *ntu; u32 count; u32 *pending; u32 *xdp_tx; struct libeth_xdpsq_lock *lock; }; /** * struct libeth_xdp_tx_desc - abstraction for an XDP Tx descriptor * @addr: DMA address of the frame * @len: length of the frame * @flags: XDP Tx flags * @opts: combined @len + @flags for speed * * Filled by the generic functions and then passed to driver-specific functions * to fill a HW Tx descriptor, always placed on the [function] stack. */ struct libeth_xdp_tx_desc { dma_addr_t addr; union { struct { u32 len; u32 flags; }; aligned_u64 opts; }; } __aligned_largest; /** * libeth_xdp_ptr_to_priv - convert pointer to a libeth_xdp u64 priv * @ptr: pointer to convert * * The main sending function passes private data as the largest scalar, u64. * Use this helper when you want to pass a pointer there. */ #define libeth_xdp_ptr_to_priv(ptr) ({ \ typecheck_pointer(ptr); \ ((u64)(uintptr_t)(ptr)); \ }) /** * libeth_xdp_priv_to_ptr - convert libeth_xdp u64 priv to a pointer * @priv: private data to convert * * The main sending function passes private data as the largest scalar, u64. * Use this helper when your callback takes this u64 and you want to convert * it back to a pointer. */ #define libeth_xdp_priv_to_ptr(priv) ({ \ static_assert(__same_type(priv, u64)); \ ((const void *)(uintptr_t)(priv)); \ }) /* * On 64-bit systems, assigning one u64 is faster than two u32s. When ::len * occupies lowest 32 bits (LE), whole ::opts can be assigned directly instead. */ #ifdef __LITTLE_ENDIAN #define __LIBETH_WORD_ACCESS 1 #endif #ifdef __LIBETH_WORD_ACCESS #define __libeth_xdp_tx_len(flen, ...) \ .opts = ((flen) | FIELD_PREP(GENMASK_ULL(63, 32), (__VA_ARGS__ + 0))) #else #define __libeth_xdp_tx_len(flen, ...) \ .len = (flen), .flags = (__VA_ARGS__ + 0) #endif /** * libeth_xdp_tx_xmit_bulk - main XDP Tx function * @bulk: array of frames to send * @xdpsq: pointer to the driver-specific XDPSQ struct * @n: number of frames to send * @unroll: whether to unroll the queue filling loop for speed * @priv: driver-specific private data * @prep: callback for cleaning the queue and filling abstract &libeth_xdpsq * @fill: internal callback for filling &libeth_sqe and &libeth_xdp_tx_desc * @xmit: callback for filling a HW descriptor with the frame info * * Internal abstraction for placing @n XDP Tx frames on the HW XDPSQ. Used for * all types of frames: ``XDP_TX``, .ndo_xdp_xmit(), XSk ``XDP_TX``, and XSk * xmit. * @prep must lock the queue as this function releases it at the end. @unroll * greatly increases the object code size, but also greatly increases XSk xmit * performance; for other types of frames, it's not enabled. * The compilers inline all those onstack abstractions to direct data accesses. * * Return: number of frames actually placed on the queue, <= @n. The function * can't fail, but can send less frames if there's no enough free descriptors * available. The actual free space is returned by @prep from the driver. */ static __always_inline u32 libeth_xdp_tx_xmit_bulk(const struct libeth_xdp_tx_frame *bulk, void *xdpsq, u32 n, bool unroll, u64 priv, u32 (*prep)(void *xdpsq, struct libeth_xdpsq *sq), struct libeth_xdp_tx_desc (*fill)(struct libeth_xdp_tx_frame frm, u32 i, const struct libeth_xdpsq *sq, u64 priv), void (*xmit)(struct libeth_xdp_tx_desc desc, u32 i, const struct libeth_xdpsq *sq, u64 priv)) { struct libeth_xdpsq sq __uninitialized; u32 this, batched, off = 0; u32 ntu, i = 0; n = min(n, prep(xdpsq, &sq)); if (unlikely(!n)) goto unlock; ntu = *sq.ntu; this = sq.count - ntu; if (likely(this > n)) this = n; again: if (!unroll) goto linear; batched = ALIGN_DOWN(this, LIBETH_XDP_TX_BATCH); for ( ; i < off + batched; i += LIBETH_XDP_TX_BATCH) { u32 base = ntu + i - off; unrolled_count(LIBETH_XDP_TX_BATCH) for (u32 j = 0; j < LIBETH_XDP_TX_BATCH; j++) xmit(fill(bulk[i + j], base + j, &sq, priv), base + j, &sq, priv); } if (batched < this) { linear: for ( ; i < off + this; i++) xmit(fill(bulk[i], ntu + i - off, &sq, priv), ntu + i - off, &sq, priv); } ntu += this; if (likely(ntu < sq.count)) goto out; ntu = 0; if (i < n) { this = n - i; off = i; goto again; } out: *sq.ntu = ntu; *sq.pending += n; if (sq.xdp_tx) *sq.xdp_tx += n; unlock: libeth_xdpsq_unlock(sq.lock); return n; } /* ``XDP_TX`` bulking */ void libeth_xdp_return_buff_slow(struct libeth_xdp_buff *xdp); /** * libeth_xdp_tx_queue_head - internal helper for queueing one ``XDP_TX`` head * @bq: XDP Tx bulk to queue the head frag to * @xdp: XDP buffer with the head to queue * * Return: false if it's the only frag of the frame, true if it's an S/G frame. */ static inline bool libeth_xdp_tx_queue_head(struct libeth_xdp_tx_bulk *bq, const struct libeth_xdp_buff *xdp) { const struct xdp_buff *base = &xdp->base; bq->bulk[bq->count++] = (typeof(*bq->bulk)){ .data = xdp->data, .len_fl = (base->data_end - xdp->data) | LIBETH_XDP_TX_FIRST, .soff = xdp_data_hard_end(base) - xdp->data, }; if (!xdp_buff_has_frags(base)) return false; bq->bulk[bq->count - 1].len_fl |= LIBETH_XDP_TX_MULTI; return true; } /** * libeth_xdp_tx_queue_frag - internal helper for queueing one ``XDP_TX`` frag * @bq: XDP Tx bulk to queue the frag to * @frag: frag to queue */ static inline void libeth_xdp_tx_queue_frag(struct libeth_xdp_tx_bulk *bq, const skb_frag_t *frag) { bq->bulk[bq->count++].frag = *frag; } /** * libeth_xdp_tx_queue_bulk - internal helper for queueing one ``XDP_TX`` frame * @bq: XDP Tx bulk to queue the frame to * @xdp: XDP buffer to queue * @flush_bulk: driver callback to flush the bulk to the HW queue * * Return: true on success, false on flush error. */ static __always_inline bool libeth_xdp_tx_queue_bulk(struct libeth_xdp_tx_bulk *bq, struct libeth_xdp_buff *xdp, bool (*flush_bulk)(struct libeth_xdp_tx_bulk *bq, u32 flags)) { const struct skb_shared_info *sinfo; bool ret = true; u32 nr_frags; if (unlikely(bq->count == LIBETH_XDP_TX_BULK) && unlikely(!flush_bulk(bq, 0))) { libeth_xdp_return_buff_slow(xdp); return false; } if (!libeth_xdp_tx_queue_head(bq, xdp)) goto out; sinfo = xdp_get_shared_info_from_buff(&xdp->base); nr_frags = sinfo->nr_frags; for (u32 i = 0; i < nr_frags; i++) { if (unlikely(bq->count == LIBETH_XDP_TX_BULK) && unlikely(!flush_bulk(bq, 0))) { ret = false; break; } libeth_xdp_tx_queue_frag(bq, &sinfo->frags[i]); } out: bq->bulk[bq->count - 1].len_fl |= LIBETH_XDP_TX_LAST; xdp->data = NULL; return ret; } /** * libeth_xdp_tx_fill_stats - fill &libeth_sqe with ``XDP_TX`` frame stats * @sqe: SQ element to fill * @desc: libeth_xdp Tx descriptor * @sinfo: &skb_shared_info for this frame * * Internal helper for filling an SQE with the frame stats, do not use in * drivers. Fills the number of frags and bytes for this frame. */ #define libeth_xdp_tx_fill_stats(sqe, desc, sinfo) \ __libeth_xdp_tx_fill_stats(sqe, desc, sinfo, __UNIQUE_ID(sqe_), \ __UNIQUE_ID(desc_), __UNIQUE_ID(sinfo_)) #define __libeth_xdp_tx_fill_stats(sqe, desc, sinfo, ue, ud, us) do { \ const struct libeth_xdp_tx_desc *ud = (desc); \ const struct skb_shared_info *us; \ struct libeth_sqe *ue = (sqe); \ \ ue->nr_frags = 1; \ ue->bytes = ud->len; \ \ if (ud->flags & LIBETH_XDP_TX_MULTI) { \ us = (sinfo); \ ue->nr_frags += us->nr_frags; \ ue->bytes += us->xdp_frags_size; \ } \ } while (0) /** * libeth_xdp_tx_fill_buf - internal helper to fill one ``XDP_TX`` &libeth_sqe * @frm: XDP Tx frame from the bulk * @i: index on the HW queue * @sq: XDPSQ abstraction for the queue * @priv: private data * * Return: XDP Tx descriptor with the synced DMA and other info to pass to * the driver callback. */ static inline struct libeth_xdp_tx_desc libeth_xdp_tx_fill_buf(struct libeth_xdp_tx_frame frm, u32 i, const struct libeth_xdpsq *sq, u64 priv) { struct libeth_xdp_tx_desc desc; struct skb_shared_info *sinfo; skb_frag_t *frag = &frm.frag; struct libeth_sqe *sqe; netmem_ref netmem; if (frm.len_fl & LIBETH_XDP_TX_FIRST) { sinfo = frm.data + frm.soff; skb_frag_fill_netmem_desc(frag, virt_to_netmem(frm.data), offset_in_page(frm.data), frm.len_fl); } else { sinfo = NULL; } netmem = skb_frag_netmem(frag); desc = (typeof(desc)){ .addr = page_pool_get_dma_addr_netmem(netmem) + skb_frag_off(frag), .len = skb_frag_size(frag) & LIBETH_XDP_TX_LEN, .flags = skb_frag_size(frag) & LIBETH_XDP_TX_FLAGS, }; dma_sync_single_for_device(__netmem_get_pp(netmem)->p.dev, desc.addr, desc.len, DMA_BIDIRECTIONAL); if (!sinfo) return desc; sqe = &sq->sqes[i]; sqe->type = LIBETH_SQE_XDP_TX; sqe->sinfo = sinfo; libeth_xdp_tx_fill_stats(sqe, &desc, sinfo); return desc; } void libeth_xdp_tx_exception(struct libeth_xdp_tx_bulk *bq, u32 sent, u32 flags); /** * __libeth_xdp_tx_flush_bulk - internal helper to flush one XDP Tx bulk * @bq: bulk to flush * @flags: XDP TX flags (.ndo_xdp_xmit(), XSk etc.) * @prep: driver-specific callback to prepare the queue for sending * @fill: libeth_xdp callback to fill &libeth_sqe and &libeth_xdp_tx_desc * @xmit: driver callback to fill a HW descriptor * * Internal abstraction to create bulk flush functions for drivers. Used for * everything except XSk xmit. * * Return: true if anything was sent, false otherwise. */ static __always_inline bool __libeth_xdp_tx_flush_bulk(struct libeth_xdp_tx_bulk *bq, u32 flags, u32 (*prep)(void *xdpsq, struct libeth_xdpsq *sq), struct libeth_xdp_tx_desc (*fill)(struct libeth_xdp_tx_frame frm, u32 i, const struct libeth_xdpsq *sq, u64 priv), void (*xmit)(struct libeth_xdp_tx_desc desc, u32 i, const struct libeth_xdpsq *sq, u64 priv)) { u32 sent, drops; int err = 0; sent = libeth_xdp_tx_xmit_bulk(bq->bulk, bq->xdpsq, min(bq->count, LIBETH_XDP_TX_BULK), false, 0, prep, fill, xmit); drops = bq->count - sent; if (unlikely(drops)) { libeth_xdp_tx_exception(bq, sent, flags); err = -ENXIO; } else { bq->count = 0; } trace_xdp_bulk_tx(bq->dev, sent, drops, err); return likely(sent); } /** * libeth_xdp_tx_flush_bulk - wrapper to define flush of one ``XDP_TX`` bulk * @bq: bulk to flush * @flags: Tx flags, see above * @prep: driver callback to prepare the queue * @xmit: driver callback to fill a HW descriptor * * Use via LIBETH_XDP_DEFINE_FLUSH_TX() to define an ``XDP_TX`` driver * callback. */ #define libeth_xdp_tx_flush_bulk(bq, flags, prep, xmit) \ __libeth_xdp_tx_flush_bulk(bq, flags, prep, libeth_xdp_tx_fill_buf, \ xmit) /* .ndo_xdp_xmit() implementation */ /** * libeth_xdp_xmit_init_bulk - internal helper to initialize bulk for XDP xmit * @bq: bulk to initialize * @dev: target &net_device * @xdpsqs: array of driver-specific XDPSQ structs * @num: number of active XDPSQs (the above array length) */ #define libeth_xdp_xmit_init_bulk(bq, dev, xdpsqs, num) \ __libeth_xdp_xmit_init_bulk(bq, dev, (xdpsqs)[libeth_xdpsq_id(num)]) static inline void __libeth_xdp_xmit_init_bulk(struct libeth_xdp_tx_bulk *bq, struct net_device *dev, void *xdpsq) { bq->dev = dev; bq->xdpsq = xdpsq; bq->count = 0; } /** * libeth_xdp_xmit_frame_dma - internal helper to access DMA of an &xdp_frame * @xf: pointer to the XDP frame * * There's no place in &libeth_xdp_tx_frame to store DMA address for an * &xdp_frame head. The headroom is used then, the address is placed right * after the frame struct, naturally aligned. * * Return: pointer to the DMA address to use. */ #define libeth_xdp_xmit_frame_dma(xf) \ _Generic((xf), \ const struct xdp_frame *: \ (const dma_addr_t *)__libeth_xdp_xmit_frame_dma(xf), \ struct xdp_frame *: \ (dma_addr_t *)__libeth_xdp_xmit_frame_dma(xf) \ ) static inline void *__libeth_xdp_xmit_frame_dma(const struct xdp_frame *xdpf) { void *addr = (void *)(xdpf + 1); if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && __alignof(*xdpf) < sizeof(dma_addr_t)) addr = PTR_ALIGN(addr, sizeof(dma_addr_t)); return addr; } /** * libeth_xdp_xmit_queue_head - internal helper for queueing one XDP xmit head * @bq: XDP Tx bulk to queue the head frag to * @xdpf: XDP frame with the head to queue * @dev: device to perform DMA mapping * * Return: ``LIBETH_XDP_DROP`` on DMA mapping error, * ``LIBETH_XDP_PASS`` if it's the only frag in the frame, * ``LIBETH_XDP_TX`` if it's an S/G frame. */ static inline u32 libeth_xdp_xmit_queue_head(struct libeth_xdp_tx_bulk *bq, struct xdp_frame *xdpf, struct device *dev) { dma_addr_t dma; dma = dma_map_single(dev, xdpf->data, xdpf->len, DMA_TO_DEVICE); if (dma_mapping_error(dev, dma)) return LIBETH_XDP_DROP; *libeth_xdp_xmit_frame_dma(xdpf) = dma; bq->bulk[bq->count++] = (typeof(*bq->bulk)){ .xdpf = xdpf, __libeth_xdp_tx_len(xdpf->len, LIBETH_XDP_TX_FIRST), }; if (!xdp_frame_has_frags(xdpf)) return LIBETH_XDP_PASS; bq->bulk[bq->count - 1].flags |= LIBETH_XDP_TX_MULTI; return LIBETH_XDP_TX; } /** * libeth_xdp_xmit_queue_frag - internal helper for queueing one XDP xmit frag * @bq: XDP Tx bulk to queue the frag to * @frag: frag to queue * @dev: device to perform DMA mapping * * Return: true on success, false on DMA mapping error. */ static inline bool libeth_xdp_xmit_queue_frag(struct libeth_xdp_tx_bulk *bq, const skb_frag_t *frag, struct device *dev) { dma_addr_t dma; dma = skb_frag_dma_map(dev, frag); if (dma_mapping_error(dev, dma)) return false; bq->bulk[bq->count++] = (typeof(*bq->bulk)){ .dma = dma, __libeth_xdp_tx_len(skb_frag_size(frag)), }; return true; } /** * libeth_xdp_xmit_queue_bulk - internal helper for queueing one XDP xmit frame * @bq: XDP Tx bulk to queue the frame to * @xdpf: XDP frame to queue * @flush_bulk: driver callback to flush the bulk to the HW queue * * Return: ``LIBETH_XDP_TX`` on success, * ``LIBETH_XDP_DROP`` if the frame should be dropped by the stack, * ``LIBETH_XDP_ABORTED`` if the frame will be dropped by libeth_xdp. */ static __always_inline u32 libeth_xdp_xmit_queue_bulk(struct libeth_xdp_tx_bulk *bq, struct xdp_frame *xdpf, bool (*flush_bulk)(struct libeth_xdp_tx_bulk *bq, u32 flags)) { u32 head, nr_frags, i, ret = LIBETH_XDP_TX; struct device *dev = bq->dev->dev.parent; const struct skb_shared_info *sinfo; if (unlikely(bq->count == LIBETH_XDP_TX_BULK) && unlikely(!flush_bulk(bq, LIBETH_XDP_TX_NDO))) return LIBETH_XDP_DROP; head = libeth_xdp_xmit_queue_head(bq, xdpf, dev); if (head == LIBETH_XDP_PASS) goto out; else if (head == LIBETH_XDP_DROP) return LIBETH_XDP_DROP; sinfo = xdp_get_shared_info_from_frame(xdpf); nr_frags = sinfo->nr_frags; for (i = 0; i < nr_frags; i++) { if (unlikely(bq->count == LIBETH_XDP_TX_BULK) && unlikely(!flush_bulk(bq, LIBETH_XDP_TX_NDO))) break; if (!libeth_xdp_xmit_queue_frag(bq, &sinfo->frags[i], dev)) break; } if (unlikely(i < nr_frags)) ret = LIBETH_XDP_ABORTED; out: bq->bulk[bq->count - 1].flags |= LIBETH_XDP_TX_LAST; return ret; } /** * libeth_xdp_xmit_fill_buf - internal helper to fill one XDP xmit &libeth_sqe * @frm: XDP Tx frame from the bulk * @i: index on the HW queue * @sq: XDPSQ abstraction for the queue * @priv: private data * * Return: XDP Tx descriptor with the mapped DMA and other info to pass to * the driver callback. */ static inline struct libeth_xdp_tx_desc libeth_xdp_xmit_fill_buf(struct libeth_xdp_tx_frame frm, u32 i, const struct libeth_xdpsq *sq, u64 priv) { struct libeth_xdp_tx_desc desc; struct libeth_sqe *sqe; struct xdp_frame *xdpf; if (frm.flags & LIBETH_XDP_TX_FIRST) { xdpf = frm.xdpf; desc.addr = *libeth_xdp_xmit_frame_dma(xdpf); } else { xdpf = NULL; desc.addr = frm.dma; } desc.opts = frm.opts; sqe = &sq->sqes[i]; dma_unmap_addr_set(sqe, dma, desc.addr); dma_unmap_len_set(sqe, len, desc.len); if (!xdpf) { sqe->type = LIBETH_SQE_XDP_XMIT_FRAG; return desc; } sqe->type = LIBETH_SQE_XDP_XMIT; sqe->xdpf = xdpf; libeth_xdp_tx_fill_stats(sqe, &desc, xdp_get_shared_info_from_frame(xdpf)); return desc; } /** * libeth_xdp_xmit_flush_bulk - wrapper to define flush of one XDP xmit bulk * @bq: bulk to flush * @flags: Tx flags, see __libeth_xdp_tx_flush_bulk() * @prep: driver callback to prepare the queue * @xmit: driver callback to fill a HW descriptor * * Use via LIBETH_XDP_DEFINE_FLUSH_XMIT() to define an XDP xmit driver * callback. */ #define libeth_xdp_xmit_flush_bulk(bq, flags, prep, xmit) \ __libeth_xdp_tx_flush_bulk(bq, (flags) | LIBETH_XDP_TX_NDO, prep, \ libeth_xdp_xmit_fill_buf, xmit) u32 libeth_xdp_xmit_return_bulk(const struct libeth_xdp_tx_frame *bq, u32 count, const struct net_device *dev); /** * __libeth_xdp_xmit_do_bulk - internal function to implement .ndo_xdp_xmit() * @bq: XDP Tx bulk to queue frames to * @frames: XDP frames passed by the stack * @n: number of frames * @flags: flags passed by the stack * @flush_bulk: driver callback to flush an XDP xmit bulk * @finalize: driver callback to finalize sending XDP Tx frames on the queue * * Perform common checks, map the frags and queue them to the bulk, then flush * the bulk to the XDPSQ. If requested by the stack, finalize the queue. * * Return: number of frames send or -errno on error. */ static __always_inline int __libeth_xdp_xmit_do_bulk(struct libeth_xdp_tx_bulk *bq, struct xdp_frame **frames, u32 n, u32 flags, bool (*flush_bulk)(struct libeth_xdp_tx_bulk *bq, u32 flags), void (*finalize)(void *xdpsq, bool sent, bool flush)) { u32 nxmit = 0; if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK)) return -EINVAL; for (u32 i = 0; likely(i < n); i++) { u32 ret; ret = libeth_xdp_xmit_queue_bulk(bq, frames[i], flush_bulk); if (unlikely(ret != LIBETH_XDP_TX)) { nxmit += ret == LIBETH_XDP_ABORTED; break; } nxmit++; } if (bq->count) { flush_bulk(bq, LIBETH_XDP_TX_NDO); if (unlikely(bq->count)) nxmit -= libeth_xdp_xmit_return_bulk(bq->bulk, bq->count, bq->dev); } finalize(bq->xdpsq, nxmit, flags & XDP_XMIT_FLUSH); return nxmit; } /** * libeth_xdp_xmit_do_bulk - implement full .ndo_xdp_xmit() in driver * @dev: target &net_device * @n: number of frames to send * @fr: XDP frames to send * @f: flags passed by the stack * @xqs: array of XDPSQs driver structs * @nqs: number of active XDPSQs, the above array length * @fl: driver callback to flush an XDP xmit bulk * @fin: driver cabback to finalize the queue * * If the driver has active XDPSQs, perform common checks and send the frames. * Finalize the queue, if requested. * * Return: number of frames sent or -errno on error. */ #define libeth_xdp_xmit_do_bulk(dev, n, fr, f, xqs, nqs, fl, fin) \ _libeth_xdp_xmit_do_bulk(dev, n, fr, f, xqs, nqs, fl, fin, \ __UNIQUE_ID(bq_), __UNIQUE_ID(ret_), \ __UNIQUE_ID(nqs_)) #define _libeth_xdp_xmit_do_bulk(d, n, fr, f, xqs, nqs, fl, fin, ub, ur, un) \ ({ \ u32 un = (nqs); \ int ur; \ \ if (likely(un)) { \ LIBETH_XDP_ONSTACK_BULK(ub); \ \ libeth_xdp_xmit_init_bulk(&ub, d, xqs, un); \ ur = __libeth_xdp_xmit_do_bulk(&ub, fr, n, f, fl, fin); \ } else { \ ur = -ENXIO; \ } \ \ ur; \ }) /* Rx polling path */ /** * libeth_xdp_tx_init_bulk - initialize an XDP Tx bulk for Rx NAPI poll * @bq: bulk to initialize * @prog: RCU pointer to the XDP program (can be %NULL) * @dev: target &net_device * @xdpsqs: array of driver XDPSQ structs * @num: number of active XDPSQs, the above array length * * Should be called on an onstack XDP Tx bulk before the NAPI polling loop. * Initializes all the needed fields to run libeth_xdp functions. If @num == 0, * assumes XDP is not enabled. * Do not use for XSk, it has its own optimized helper. */ #define libeth_xdp_tx_init_bulk(bq, prog, dev, xdpsqs, num) \ __libeth_xdp_tx_init_bulk(bq, prog, dev, xdpsqs, num, false, \ __UNIQUE_ID(bq_), __UNIQUE_ID(nqs_)) #define __libeth_xdp_tx_init_bulk(bq, pr, d, xdpsqs, num, xsk, ub, un) do { \ typeof(bq) ub = (bq); \ u32 un = (num); \ \ rcu_read_lock(); \ \ if (un || (xsk)) { \ ub->prog = rcu_dereference(pr); \ ub->dev = (d); \ ub->xdpsq = (xdpsqs)[libeth_xdpsq_id(un)]; \ } else { \ ub->prog = NULL; \ } \ \ ub->act_mask = 0; \ ub->count = 0; \ } while (0) void libeth_xdp_load_stash(struct libeth_xdp_buff *dst, const struct libeth_xdp_buff_stash *src); void libeth_xdp_save_stash(struct libeth_xdp_buff_stash *dst, const struct libeth_xdp_buff *src); void __libeth_xdp_return_stash(struct libeth_xdp_buff_stash *stash); /** * libeth_xdp_init_buff - initialize a &libeth_xdp_buff for Rx NAPI poll * @dst: onstack buffer to initialize * @src: XDP buffer stash placed on the queue * @rxq: registered &xdp_rxq_info corresponding to this queue * * Should be called before the main NAPI polling loop. Loads the content of * the previously saved stash or initializes the buffer from scratch. * Do not use for XSk. */ static inline void libeth_xdp_init_buff(struct libeth_xdp_buff *dst, const struct libeth_xdp_buff_stash *src, struct xdp_rxq_info *rxq) { if (likely(!src->data)) dst->data = NULL; else libeth_xdp_load_stash(dst, src); dst->base.rxq = rxq; } /** * libeth_xdp_save_buff - save a partially built buffer on a queue * @dst: XDP buffer stash placed on the queue * @src: onstack buffer to save * * Should be called after the main NAPI polling loop. If the loop exited before * the buffer was finished, saves its content on the queue, so that it can be * completed during the next poll. Otherwise, clears the stash. */ static inline void libeth_xdp_save_buff(struct libeth_xdp_buff_stash *dst, const struct libeth_xdp_buff *src) { if (likely(!src->data)) dst->data = NULL; else libeth_xdp_save_stash(dst, src); } /** * libeth_xdp_return_stash - free an XDP buffer stash from a queue * @stash: stash to free * * If the queue is about to be destroyed, but it still has an incompleted * buffer stash, this helper should be called to free it. */ static inline void libeth_xdp_return_stash(struct libeth_xdp_buff_stash *stash) { if (stash->data) __libeth_xdp_return_stash(stash); } static inline void libeth_xdp_return_va(const void *data, bool napi) { netmem_ref netmem = virt_to_netmem(data); page_pool_put_full_netmem(__netmem_get_pp(netmem), netmem, napi); } static inline void libeth_xdp_return_frags(const struct skb_shared_info *sinfo, bool napi) { for (u32 i = 0; i < sinfo->nr_frags; i++) { netmem_ref netmem = skb_frag_netmem(&sinfo->frags[i]); page_pool_put_full_netmem(netmem_get_pp(netmem), netmem, napi); } } /** * libeth_xdp_return_buff - free/recycle &libeth_xdp_buff * @xdp: buffer to free * * Hotpath helper to free &libeth_xdp_buff. Comparing to xdp_return_buff(), * it's faster as it gets inlined and always assumes order-0 pages and safe * direct recycling. Zeroes @xdp->data to avoid UAFs. */ #define libeth_xdp_return_buff(xdp) __libeth_xdp_return_buff(xdp, true) static inline void __libeth_xdp_return_buff(struct libeth_xdp_buff *xdp, bool napi) { if (!xdp_buff_has_frags(&xdp->base)) goto out; libeth_xdp_return_frags(xdp_get_shared_info_from_buff(&xdp->base), napi); out: libeth_xdp_return_va(xdp->data, napi); xdp->data = NULL; } bool libeth_xdp_buff_add_frag(struct libeth_xdp_buff *xdp, const struct libeth_fqe *fqe, u32 len); /** * libeth_xdp_prepare_buff - fill &libeth_xdp_buff with head FQE data * @xdp: XDP buffer to attach the head to * @fqe: FQE containing the head buffer * @len: buffer len passed from HW * * Internal, use libeth_xdp_process_buff() instead. Initializes XDP buffer * head with the Rx buffer data: data pointer, length, headroom, and * truesize/tailroom. Zeroes the flags. * Uses faster single u64 write instead of per-field access. */ static inline void libeth_xdp_prepare_buff(struct libeth_xdp_buff *xdp, const struct libeth_fqe *fqe, u32 len) { const struct page *page = __netmem_to_page(fqe->netmem); #ifdef __LIBETH_WORD_ACCESS static_assert(offsetofend(typeof(xdp->base), flags) - offsetof(typeof(xdp->base), frame_sz) == sizeof(u64)); *(u64 *)&xdp->base.frame_sz = fqe->truesize; #else xdp_init_buff(&xdp->base, fqe->truesize, xdp->base.rxq); #endif xdp_prepare_buff(&xdp->base, page_address(page) + fqe->offset, pp_page_to_nmdesc(page)->pp->p.offset, len, true); } /** * libeth_xdp_process_buff - attach Rx buffer to &libeth_xdp_buff * @xdp: XDP buffer to attach the Rx buffer to * @fqe: Rx buffer to process * @len: received data length from the descriptor * * If the XDP buffer is empty, attaches the Rx buffer as head and initializes * the required fields. Otherwise, attaches the buffer as a frag. * Already performs DMA sync-for-CPU and frame start prefetch * (for head buffers only). * * Return: true on success, false if the descriptor must be skipped (empty or * no space for a new frag). */ static inline bool libeth_xdp_process_buff(struct libeth_xdp_buff *xdp, const struct libeth_fqe *fqe, u32 len) { if (!libeth_rx_sync_for_cpu(fqe, len)) return false; if (xdp->data) return libeth_xdp_buff_add_frag(xdp, fqe, len); libeth_xdp_prepare_buff(xdp, fqe, len); prefetch(xdp->data); return true; } /** * libeth_xdp_buff_stats_frags - update onstack RQ stats with XDP frags info * @ss: onstack stats to update * @xdp: buffer to account * * Internal helper used by __libeth_xdp_run_pass(), do not call directly. * Adds buffer's frags count and total len to the onstack stats. */ static inline void libeth_xdp_buff_stats_frags(struct libeth_rq_napi_stats *ss, const struct libeth_xdp_buff *xdp) { const struct skb_shared_info *sinfo; sinfo = xdp_get_shared_info_from_buff(&xdp->base); ss->bytes += sinfo->xdp_frags_size; ss->fragments += sinfo->nr_frags + 1; } u32 libeth_xdp_prog_exception(const struct libeth_xdp_tx_bulk *bq, struct libeth_xdp_buff *xdp, enum xdp_action act, int ret); /** * __libeth_xdp_run_prog - run XDP program on an XDP buffer * @xdp: XDP buffer to run the prog on * @bq: buffer bulk for ``XDP_TX`` queueing * * Internal inline abstraction to run XDP program. Handles ``XDP_DROP`` * and ``XDP_REDIRECT`` only, the rest is processed levels up. * Reports an XDP prog exception on errors. * * Return: libeth_xdp prog verdict depending on the prog's verdict. */ static __always_inline u32 __libeth_xdp_run_prog(struct libeth_xdp_buff *xdp, const struct libeth_xdp_tx_bulk *bq) { enum xdp_action act; act = bpf_prog_run_xdp(bq->prog, &xdp->base); if (unlikely(act < XDP_DROP || act > XDP_REDIRECT)) goto out; switch (act) { case XDP_PASS: return LIBETH_XDP_PASS; case XDP_DROP: libeth_xdp_return_buff(xdp); return LIBETH_XDP_DROP; case XDP_TX: return LIBETH_XDP_TX; case XDP_REDIRECT: if (unlikely(xdp_do_redirect(bq->dev, &xdp->base, bq->prog))) break; xdp->data = NULL; return LIBETH_XDP_REDIRECT; default: break; } out: return libeth_xdp_prog_exception(bq, xdp, act, 0); } /** * __libeth_xdp_run_flush - run XDP program and handle ``XDP_TX`` verdict * @xdp: XDP buffer to run the prog on * @bq: buffer bulk for ``XDP_TX`` queueing * @run: internal callback for running XDP program * @queue: internal callback for queuing ``XDP_TX`` frame * @flush_bulk: driver callback for flushing a bulk * * Internal inline abstraction to run XDP program and additionally handle * ``XDP_TX`` verdict. Used by both XDP and XSk, hence @run and @queue. * Do not use directly. * * Return: libeth_xdp prog verdict depending on the prog's verdict. */ static __always_inline u32 __libeth_xdp_run_flush(struct libeth_xdp_buff *xdp, struct libeth_xdp_tx_bulk *bq, u32 (*run)(struct libeth_xdp_buff *xdp, const struct libeth_xdp_tx_bulk *bq), bool (*queue)(struct libeth_xdp_tx_bulk *bq, struct libeth_xdp_buff *xdp, bool (*flush_bulk) (struct libeth_xdp_tx_bulk *bq, u32 flags)), bool (*flush_bulk)(struct libeth_xdp_tx_bulk *bq, u32 flags)) { u32 act; act = run(xdp, bq); if (act == LIBETH_XDP_TX && unlikely(!queue(bq, xdp, flush_bulk))) act = LIBETH_XDP_DROP; bq->act_mask |= act; return act; } /** * libeth_xdp_run_prog - run XDP program (non-XSk path) and handle all verdicts * @xdp: XDP buffer to process * @bq: XDP Tx bulk to queue ``XDP_TX`` buffers * @fl: driver ``XDP_TX`` bulk flush callback * * Run the attached XDP program and handle all possible verdicts. XSk has its * own version. * Prefer using it via LIBETH_XDP_DEFINE_RUN{,_PASS,_PROG}(). * * Return: true if the buffer should be passed up the stack, false if the poll * should go to the next buffer. */ #define libeth_xdp_run_prog(xdp, bq, fl) \ (__libeth_xdp_run_flush(xdp, bq, __libeth_xdp_run_prog, \ libeth_xdp_tx_queue_bulk, \ fl) == LIBETH_XDP_PASS) /** * __libeth_xdp_run_pass - helper to run XDP program and handle the result * @xdp: XDP buffer to process * @bq: XDP Tx bulk to queue ``XDP_TX`` frames * @napi: NAPI to build an skb and pass it up the stack * @rs: onstack libeth RQ stats * @md: metadata that should be filled to the XDP buffer * @prep: callback for filling the metadata * @run: driver wrapper to run XDP program * @populate: driver callback to populate an skb with the HW descriptor data * * Inline abstraction that does the following (non-XSk path): * 1) adds frame size and frag number (if needed) to the onstack stats; * 2) fills the descriptor metadata to the onstack &libeth_xdp_buff * 3) runs XDP program if present; * 4) handles all possible verdicts; * 5) on ``XDP_PASS`, builds an skb from the buffer; * 6) populates it with the descriptor metadata; * 7) passes it up the stack. * * In most cases, number 2 means just writing the pointer to the HW descriptor * to the XDP buffer. If so, please use LIBETH_XDP_DEFINE_RUN{,_PASS}() * wrappers to build a driver function. */ static __always_inline void __libeth_xdp_run_pass(struct libeth_xdp_buff *xdp, struct libeth_xdp_tx_bulk *bq, struct napi_struct *napi, struct libeth_rq_napi_stats *rs, const void *md, void (*prep)(struct libeth_xdp_buff *xdp, const void *md), bool (*run)(struct libeth_xdp_buff *xdp, struct libeth_xdp_tx_bulk *bq), bool (*populate)(struct sk_buff *skb, const struct libeth_xdp_buff *xdp, struct libeth_rq_napi_stats *rs)) { struct sk_buff *skb; rs->bytes += xdp->base.data_end - xdp->data; rs->packets++; if (xdp_buff_has_frags(&xdp->base)) libeth_xdp_buff_stats_frags(rs, xdp); if (prep && (!__builtin_constant_p(!!md) || md)) prep(xdp, md); if (!bq || !run || !bq->prog) goto build; if (!run(xdp, bq)) return; build: skb = xdp_build_skb_from_buff(&xdp->base); if (unlikely(!skb)) { libeth_xdp_return_buff_slow(xdp); return; } xdp->data = NULL; if (unlikely(!populate(skb, xdp, rs))) { napi_consume_skb(skb, true); return; } napi_gro_receive(napi, skb); } static inline void libeth_xdp_prep_desc(struct libeth_xdp_buff *xdp, const void *desc) { xdp->desc = desc; } /** * libeth_xdp_run_pass - helper to run XDP program and handle the result * @xdp: XDP buffer to process * @bq: XDP Tx bulk to queue ``XDP_TX`` frames * @napi: NAPI to build an skb and pass it up the stack * @ss: onstack libeth RQ stats * @desc: pointer to the HW descriptor for that frame * @run: driver wrapper to run XDP program * @populate: driver callback to populate an skb with the HW descriptor data * * Wrapper around the underscored version when "fill the descriptor metadata" * means just writing the pointer to the HW descriptor as @xdp->desc. */ #define libeth_xdp_run_pass(xdp, bq, napi, ss, desc, run, populate) \ __libeth_xdp_run_pass(xdp, bq, napi, ss, desc, libeth_xdp_prep_desc, \ run, populate) /** * libeth_xdp_finalize_rx - finalize XDPSQ after a NAPI polling loop (non-XSk) * @bq: ``XDP_TX`` frame bulk * @flush: driver callback to flush the bulk * @finalize: driver callback to start sending the frames and run the timer * * Flush the bulk if there are frames left to send, kick the queue and flush * the XDP maps. */ #define libeth_xdp_finalize_rx(bq, flush, finalize) \ __libeth_xdp_finalize_rx(bq, 0, flush, finalize) static __always_inline void __libeth_xdp_finalize_rx(struct libeth_xdp_tx_bulk *bq, u32 flags, bool (*flush_bulk)(struct libeth_xdp_tx_bulk *bq, u32 flags), void (*finalize)(void *xdpsq, bool sent, bool flush)) { if (bq->act_mask & LIBETH_XDP_TX) { if (bq->count) flush_bulk(bq, flags | LIBETH_XDP_TX_DROP); finalize(bq->xdpsq, true, true); } if (bq->act_mask & LIBETH_XDP_REDIRECT) xdp_do_flush(); rcu_read_unlock(); } /* * Helpers to reduce boilerplate code in drivers. * * Typical driver Rx flow would be (excl. bulk and buff init, frag attach): * * LIBETH_XDP_DEFINE_START(); * LIBETH_XDP_DEFINE_FLUSH_TX(static driver_xdp_flush_tx, driver_xdp_tx_prep, * driver_xdp_xmit); * LIBETH_XDP_DEFINE_RUN(static driver_xdp_run, driver_xdp_run_prog, * driver_xdp_flush_tx, driver_populate_skb); * LIBETH_XDP_DEFINE_FINALIZE(static driver_xdp_finalize_rx, * driver_xdp_flush_tx, driver_xdp_finalize_sq); * LIBETH_XDP_DEFINE_END(); * * This will build a set of 4 static functions. The compiler is free to decide * whether to inline them. * Then, in the NAPI polling function: * * while (packets < budget) { * // ... * driver_xdp_run(xdp, &bq, napi, &rs, desc); * } * driver_xdp_finalize_rx(&bq); */ #define LIBETH_XDP_DEFINE_START() \ __diag_push(); \ __diag_ignore(GCC, 8, "-Wold-style-declaration", \ "Allow specifying \'static\' after the return type") /** * LIBETH_XDP_DEFINE_TIMER - define a driver XDPSQ cleanup timer callback * @name: name of the function to define * @poll: Tx polling/completion function */ #define LIBETH_XDP_DEFINE_TIMER(name, poll) \ void name(struct work_struct *work) \ { \ libeth_xdpsq_run_timer(work, poll); \ } /** * LIBETH_XDP_DEFINE_FLUSH_TX - define a driver ``XDP_TX`` bulk flush function * @name: name of the function to define * @prep: driver callback to clean an XDPSQ * @xmit: driver callback to write a HW Tx descriptor */ #define LIBETH_XDP_DEFINE_FLUSH_TX(name, prep, xmit) \ __LIBETH_XDP_DEFINE_FLUSH_TX(name, prep, xmit, xdp) #define __LIBETH_XDP_DEFINE_FLUSH_TX(name, prep, xmit, pfx) \ bool name(struct libeth_xdp_tx_bulk *bq, u32 flags) \ { \ return libeth_##pfx##_tx_flush_bulk(bq, flags, prep, xmit); \ } /** * LIBETH_XDP_DEFINE_FLUSH_XMIT - define a driver XDP xmit bulk flush function * @name: name of the function to define * @prep: driver callback to clean an XDPSQ * @xmit: driver callback to write a HW Tx descriptor */ #define LIBETH_XDP_DEFINE_FLUSH_XMIT(name, prep, xmit) \ bool name(struct libeth_xdp_tx_bulk *bq, u32 flags) \ { \ return libeth_xdp_xmit_flush_bulk(bq, flags, prep, xmit); \ } /** * LIBETH_XDP_DEFINE_RUN_PROG - define a driver XDP program run function * @name: name of the function to define * @flush: driver callback to flush an ``XDP_TX`` bulk */ #define LIBETH_XDP_DEFINE_RUN_PROG(name, flush) \ bool __LIBETH_XDP_DEFINE_RUN_PROG(name, flush, xdp) #define __LIBETH_XDP_DEFINE_RUN_PROG(name, flush, pfx) \ name(struct libeth_xdp_buff *xdp, struct libeth_xdp_tx_bulk *bq) \ { \ return libeth_##pfx##_run_prog(xdp, bq, flush); \ } /** * LIBETH_XDP_DEFINE_RUN_PASS - define a driver buffer process + pass function * @name: name of the function to define * @run: driver callback to run XDP program (above) * @populate: driver callback to fill an skb with HW descriptor info */ #define LIBETH_XDP_DEFINE_RUN_PASS(name, run, populate) \ void __LIBETH_XDP_DEFINE_RUN_PASS(name, run, populate, xdp) #define __LIBETH_XDP_DEFINE_RUN_PASS(name, run, populate, pfx) \ name(struct libeth_xdp_buff *xdp, struct libeth_xdp_tx_bulk *bq, \ struct napi_struct *napi, struct libeth_rq_napi_stats *ss, \ const void *desc) \ { \ return libeth_##pfx##_run_pass(xdp, bq, napi, ss, desc, run, \ populate); \ } /** * LIBETH_XDP_DEFINE_RUN - define a driver buffer process, run + pass function * @name: name of the function to define * @run: name of the XDP prog run function to define * @flush: driver callback to flush an ``XDP_TX`` bulk * @populate: driver callback to fill an skb with HW descriptor info */ #define LIBETH_XDP_DEFINE_RUN(name, run, flush, populate) \ __LIBETH_XDP_DEFINE_RUN(name, run, flush, populate, XDP) #define __LIBETH_XDP_DEFINE_RUN(name, run, flush, populate, pfx) \ LIBETH_##pfx##_DEFINE_RUN_PROG(static run, flush); \ LIBETH_##pfx##_DEFINE_RUN_PASS(name, run, populate) /** * LIBETH_XDP_DEFINE_FINALIZE - define a driver Rx NAPI poll finalize function * @name: name of the function to define * @flush: driver callback to flush an ``XDP_TX`` bulk * @finalize: driver callback to finalize an XDPSQ and run the timer */ #define LIBETH_XDP_DEFINE_FINALIZE(name, flush, finalize) \ __LIBETH_XDP_DEFINE_FINALIZE(name, flush, finalize, xdp) #define __LIBETH_XDP_DEFINE_FINALIZE(name, flush, finalize, pfx) \ void name(struct libeth_xdp_tx_bulk *bq) \ { \ libeth_##pfx##_finalize_rx(bq, flush, finalize); \ } #define LIBETH_XDP_DEFINE_END() __diag_pop() /* XMO */ /** * libeth_xdp_buff_to_rq - get RQ pointer from an XDP buffer pointer * @xdp: &libeth_xdp_buff corresponding to the queue * @type: typeof() of the driver Rx queue structure * @member: name of &xdp_rxq_info inside @type * * Often times, pointer to the RQ is needed when reading/filling metadata from * HW descriptors. The helper can be used to quickly jump from an XDP buffer * to the queue corresponding to its &xdp_rxq_info without introducing * additional fields (&libeth_xdp_buff is precisely 1 cacheline long on x64). */ #define libeth_xdp_buff_to_rq(xdp, type, member) \ container_of_const((xdp)->base.rxq, type, member) /** * libeth_xdpmo_rx_hash - convert &libeth_rx_pt to an XDP RSS hash metadata * @hash: pointer to the variable to write the hash to * @rss_type: pointer to the variable to write the hash type to * @val: hash value from the HW descriptor * @pt: libeth parsed packet type * * Handle zeroed/non-available hash and convert libeth parsed packet type to * the corresponding XDP RSS hash type. To be called at the end of * xdp_metadata_ops idpf_xdpmo::xmo_rx_hash() implementation. * Note that if the driver doesn't use a constant packet type lookup table but * generates it at runtime, it must call libeth_rx_pt_gen_hash_type(pt) to * generate XDP RSS hash type for each packet type. * * Return: 0 on success, -ENODATA when the hash is not available. */ static inline int libeth_xdpmo_rx_hash(u32 *hash, enum xdp_rss_hash_type *rss_type, u32 val, struct libeth_rx_pt pt) { if (unlikely(!val)) return -ENODATA; *hash = val; *rss_type = pt.hash_type; return 0; } /* Tx buffer completion */ void libeth_xdp_return_buff_bulk(const struct skb_shared_info *sinfo, struct xdp_frame_bulk *bq, bool frags); void libeth_xsk_buff_free_slow(struct libeth_xdp_buff *xdp); /** * __libeth_xdp_complete_tx - complete sent XDPSQE * @sqe: SQ element / Tx buffer to complete * @cp: Tx polling/completion params * @bulk: internal callback to bulk-free ``XDP_TX`` buffers * @xsk: internal callback to free XSk ``XDP_TX`` buffers * * Use the non-underscored version in drivers instead. This one is shared * internally with libeth_tx_complete_any(). * Complete an XDPSQE of any type of XDP frame. This includes DMA unmapping * when needed, buffer freeing, stats update, and SQE invalidation. */ static __always_inline void __libeth_xdp_complete_tx(struct libeth_sqe *sqe, struct libeth_cq_pp *cp, typeof(libeth_xdp_return_buff_bulk) bulk, typeof(libeth_xsk_buff_free_slow) xsk) { enum libeth_sqe_type type = sqe->type; switch (type) { case LIBETH_SQE_EMPTY: return; case LIBETH_SQE_XDP_XMIT: case LIBETH_SQE_XDP_XMIT_FRAG: dma_unmap_page(cp->dev, dma_unmap_addr(sqe, dma), dma_unmap_len(sqe, len), DMA_TO_DEVICE); break; default: break; } switch (type) { case LIBETH_SQE_XDP_TX: bulk(sqe->sinfo, cp->bq, sqe->nr_frags != 1); break; case LIBETH_SQE_XDP_XMIT: xdp_return_frame_bulk(sqe->xdpf, cp->bq); break; case LIBETH_SQE_XSK_TX: case LIBETH_SQE_XSK_TX_FRAG: xsk(sqe->xsk); break; default: break; } switch (type) { case LIBETH_SQE_XDP_TX: case LIBETH_SQE_XDP_XMIT: case LIBETH_SQE_XSK_TX: cp->xdp_tx -= sqe->nr_frags; cp->xss->packets++; cp->xss->bytes += sqe->bytes; break; default: break; } sqe->type = LIBETH_SQE_EMPTY; } static inline void libeth_xdp_complete_tx(struct libeth_sqe *sqe, struct libeth_cq_pp *cp) { __libeth_xdp_complete_tx(sqe, cp, libeth_xdp_return_buff_bulk, libeth_xsk_buff_free_slow); } /* Misc */ u32 libeth_xdp_queue_threshold(u32 count); void __libeth_xdp_set_features(struct net_device *dev, const struct xdp_metadata_ops *xmo, u32 zc_segs, const struct xsk_tx_metadata_ops *tmo); void libeth_xdp_set_redirect(struct net_device *dev, bool enable); /** * libeth_xdp_set_features - set XDP features for netdev * @dev: &net_device to configure * @...: optional params, see __libeth_xdp_set_features() * * Set all the features libeth_xdp supports, including .ndo_xdp_xmit(). That * said, it should be used only when XDPSQs are always available regardless * of whether an XDP prog is attached to @dev. */ #define libeth_xdp_set_features(dev, ...) \ CONCATENATE(__libeth_xdp_feat, \ COUNT_ARGS(__VA_ARGS__))(dev, ##__VA_ARGS__) #define __libeth_xdp_feat0(dev) \ __libeth_xdp_set_features(dev, NULL, 0, NULL) #define __libeth_xdp_feat1(dev, xmo) \ __libeth_xdp_set_features(dev, xmo, 0, NULL) #define __libeth_xdp_feat2(dev, xmo, zc_segs) \ __libeth_xdp_set_features(dev, xmo, zc_segs, NULL) #define __libeth_xdp_feat3(dev, xmo, zc_segs, tmo) \ __libeth_xdp_set_features(dev, xmo, zc_segs, tmo) /** * libeth_xdp_set_features_noredir - enable all libeth_xdp features w/o redir * @dev: target &net_device * @...: optional params, see __libeth_xdp_set_features() * * Enable everything except the .ndo_xdp_xmit() feature, use when XDPSQs are * not available right after netdev registration. */ #define libeth_xdp_set_features_noredir(dev, ...) \ __libeth_xdp_set_features_noredir(dev, __UNIQUE_ID(dev_), \ ##__VA_ARGS__) #define __libeth_xdp_set_features_noredir(dev, ud, ...) do { \ struct net_device *ud = (dev); \ \ libeth_xdp_set_features(ud, ##__VA_ARGS__); \ libeth_xdp_set_redirect(ud, false); \ } while (0) #define libeth_xsktmo ((const void *)GOLDEN_RATIO_PRIME) #endif /* __LIBETH_XDP_H */