25  * gve_tx_fifo_* manages the Registered Segment as a FIFO - clients must
29 static int gve_tx_fifo_init(struct gve_priv *priv, struct gve_tx_fifo *fifo)  in gve_tx_fifo_init()  argument
31 	fifo->base = vmap(fifo->qpl->pages, fifo->qpl->num_entries, VM_MAP,  in gve_tx_fifo_init()
33 	if (unlikely(!fifo->base)) {  in gve_tx_fifo_init()
34 		netif_err(priv, drv, priv->dev, "Failed to vmap fifo, qpl_id = %d\n",  in gve_tx_fifo_init()
35 			  fifo->qpl->id);  in gve_tx_fifo_init()
39 	fifo->size = fifo->qpl->num_entries * PAGE_SIZE;  in gve_tx_fifo_init()
40 	atomic_set(&fifo->available, fifo->size);  in gve_tx_fifo_init()
41 	fifo->head = 0;  in gve_tx_fifo_init()
45 static void gve_tx_fifo_release(struct gve_priv *priv, struct gve_tx_fifo *fifo)  in gve_tx_fifo_release()  argument
47 	WARN(atomic_read(&fifo->available) != fifo->size,  in gve_tx_fifo_release()
48 	     "Releasing non-empty fifo");  in gve_tx_fifo_release()
50 	vunmap(fifo->base);  in gve_tx_fifo_release()
53 static int gve_tx_fifo_pad_alloc_one_frag(struct gve_tx_fifo *fifo,  in gve_tx_fifo_pad_alloc_one_frag()  argument
56 	return (fifo->head + bytes < fifo->size) ? 0 : fifo->size - fifo->head;  in gve_tx_fifo_pad_alloc_one_frag()
59 static bool gve_tx_fifo_can_alloc(struct gve_tx_fifo *fifo, size_t bytes)  in gve_tx_fifo_can_alloc()  argument
61 	return (atomic_read(&fifo->available) <= bytes) ? false : true;  in gve_tx_fifo_can_alloc()
64 /* gve_tx_alloc_fifo - Allocate fragment(s) from Tx FIFO
65  * @fifo: FIFO to allocate from
71  * Allocations from a given FIFO must be externally synchronized but concurrent
74 static int gve_tx_alloc_fifo(struct gve_tx_fifo *fifo, size_t bytes,  in gve_tx_alloc_fifo()  argument
86 	 * because the FIFO head always start aligned, and the FIFO's boundaries  in gve_tx_alloc_fifo()
90 	WARN(!gve_tx_fifo_can_alloc(fifo, bytes),  in gve_tx_alloc_fifo()
91 	     "Reached %s when there's not enough space in the fifo", __func__);  in gve_tx_alloc_fifo()
95 	iov[0].iov_offset = fifo->head;  in gve_tx_alloc_fifo()
97 	fifo->head += bytes;  in gve_tx_alloc_fifo()
99 	if (fifo->head > fifo->size) {  in gve_tx_alloc_fifo()
101 		 * FIFO, also use the head fragment.  in gve_tx_alloc_fifo()
104 		overflow = fifo->head - fifo->size;  in gve_tx_alloc_fifo()
106 		iov[1].iov_offset = 0;	/* Start of fifo*/  in gve_tx_alloc_fifo()
109 		fifo->head = overflow;  in gve_tx_alloc_fifo()
113 	aligned_head = L1_CACHE_ALIGN(fifo->head);  in gve_tx_alloc_fifo()
114 	padding = aligned_head - fifo->head;  in gve_tx_alloc_fifo()
116 	atomic_sub(bytes + padding, &fifo->available);  in gve_tx_alloc_fifo()
117 	fifo->head = aligned_head;  in gve_tx_alloc_fifo()
119 	if (fifo->head == fifo->size)  in gve_tx_alloc_fifo()
120 		fifo->head = 0;  in gve_tx_alloc_fifo()
125 /* gve_tx_free_fifo - Return space to Tx FIFO
126  * @fifo: FIFO to return fragments to
129 static void gve_tx_free_fifo(struct gve_tx_fifo *fifo, size_t bytes)  in gve_tx_free_fifo()  argument
131 	atomic_add(bytes, &fifo->available);  in gve_tx_free_fifo()
211 	/* map Tx FIFO */  in gve_tx_alloc_ring()
305  * the beginning of the payload at the end of the FIFO, and 1 if the
306  * payload wraps to the beginning of the FIFO.
310 /* Check if sufficient resources (descriptor ring space, FIFO space) are
434 	 * of the fifo and then put the header at the beginning of the fifo.  in gve_tx_add_skb()
534 			/* FIFO free */  in gve_clean_tx_done()