1 | // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause |
2 | /* |
3 | * Copyright(c) 2017 - 2018 Intel Corporation. |
4 | */ |
5 | |
6 | /* |
7 | * This file contains HFI1 support for VNIC SDMA functionality |
8 | */ |
9 | |
10 | #include "sdma.h" |
11 | #include "vnic.h" |
12 | |
13 | #define HFI1_VNIC_SDMA_Q_ACTIVE BIT(0) |
14 | #define HFI1_VNIC_SDMA_Q_DEFERRED BIT(1) |
15 | |
16 | #define HFI1_VNIC_TXREQ_NAME_LEN 32 |
17 | #define HFI1_VNIC_SDMA_DESC_WTRMRK 64 |
18 | |
19 | /* |
20 | * struct vnic_txreq - VNIC transmit descriptor |
21 | * @txreq: sdma transmit request |
22 | * @sdma: vnic sdma pointer |
23 | * @skb: skb to send |
24 | * @pad: pad buffer |
25 | * @plen: pad length |
26 | * @pbc_val: pbc value |
27 | */ |
28 | struct vnic_txreq { |
29 | struct sdma_txreq txreq; |
30 | struct hfi1_vnic_sdma *sdma; |
31 | |
32 | struct sk_buff *skb; |
33 | unsigned char pad[HFI1_VNIC_MAX_PAD]; |
34 | u16 plen; |
35 | __le64 pbc_val; |
36 | }; |
37 | |
38 | static void vnic_sdma_complete(struct sdma_txreq *txreq, |
39 | int status) |
40 | { |
41 | struct vnic_txreq *tx = container_of(txreq, struct vnic_txreq, txreq); |
42 | struct hfi1_vnic_sdma *vnic_sdma = tx->sdma; |
43 | |
44 | sdma_txclean(dd: vnic_sdma->dd, tx: txreq); |
45 | dev_kfree_skb_any(skb: tx->skb); |
46 | kmem_cache_free(s: vnic_sdma->dd->vnic.txreq_cache, objp: tx); |
47 | } |
48 | |
49 | static noinline int build_vnic_ulp_payload(struct sdma_engine *sde, |
50 | struct vnic_txreq *tx) |
51 | { |
52 | int i, ret = 0; |
53 | |
54 | ret = sdma_txadd_kvaddr( |
55 | dd: sde->dd, |
56 | tx: &tx->txreq, |
57 | kvaddr: tx->skb->data, |
58 | len: skb_headlen(skb: tx->skb)); |
59 | if (unlikely(ret)) |
60 | goto bail_txadd; |
61 | |
62 | for (i = 0; i < skb_shinfo(tx->skb)->nr_frags; i++) { |
63 | skb_frag_t *frag = &skb_shinfo(tx->skb)->frags[i]; |
64 | |
65 | /* combine physically continuous fragments later? */ |
66 | ret = sdma_txadd_page(dd: sde->dd, |
67 | tx: &tx->txreq, |
68 | page: skb_frag_page(frag), |
69 | offset: skb_frag_off(frag), |
70 | len: skb_frag_size(frag), |
71 | NULL, NULL, NULL); |
72 | if (unlikely(ret)) |
73 | goto bail_txadd; |
74 | } |
75 | |
76 | if (tx->plen) |
77 | ret = sdma_txadd_kvaddr(dd: sde->dd, tx: &tx->txreq, |
78 | kvaddr: tx->pad + HFI1_VNIC_MAX_PAD - tx->plen, |
79 | len: tx->plen); |
80 | |
81 | bail_txadd: |
82 | return ret; |
83 | } |
84 | |
85 | static int build_vnic_tx_desc(struct sdma_engine *sde, |
86 | struct vnic_txreq *tx, |
87 | u64 pbc) |
88 | { |
89 | int ret = 0; |
90 | u16 hdrbytes = 2 << 2; /* PBC */ |
91 | |
92 | ret = sdma_txinit_ahg( |
93 | tx: &tx->txreq, |
94 | flags: 0, |
95 | tlen: hdrbytes + tx->skb->len + tx->plen, |
96 | ahg_entry: 0, |
97 | num_ahg: 0, |
98 | NULL, |
99 | ahg_hlen: 0, |
100 | cb: vnic_sdma_complete); |
101 | if (unlikely(ret)) |
102 | goto bail_txadd; |
103 | |
104 | /* add pbc */ |
105 | tx->pbc_val = cpu_to_le64(pbc); |
106 | ret = sdma_txadd_kvaddr( |
107 | dd: sde->dd, |
108 | tx: &tx->txreq, |
109 | kvaddr: &tx->pbc_val, |
110 | len: hdrbytes); |
111 | if (unlikely(ret)) |
112 | goto bail_txadd; |
113 | |
114 | /* add the ulp payload */ |
115 | ret = build_vnic_ulp_payload(sde, tx); |
116 | bail_txadd: |
117 | return ret; |
118 | } |
119 | |
120 | /* setup the last plen bypes of pad */ |
121 | static inline void hfi1_vnic_update_pad(unsigned char *pad, u8 plen) |
122 | { |
123 | pad[HFI1_VNIC_MAX_PAD - 1] = plen - OPA_VNIC_ICRC_TAIL_LEN; |
124 | } |
125 | |
126 | int hfi1_vnic_send_dma(struct hfi1_devdata *dd, u8 q_idx, |
127 | struct hfi1_vnic_vport_info *vinfo, |
128 | struct sk_buff *skb, u64 pbc, u8 plen) |
129 | { |
130 | struct hfi1_vnic_sdma *vnic_sdma = &vinfo->sdma[q_idx]; |
131 | struct sdma_engine *sde = vnic_sdma->sde; |
132 | struct vnic_txreq *tx; |
133 | int ret = -ECOMM; |
134 | |
135 | if (unlikely(READ_ONCE(vnic_sdma->state) != HFI1_VNIC_SDMA_Q_ACTIVE)) |
136 | goto tx_err; |
137 | |
138 | if (unlikely(!sde || !sdma_running(sde))) |
139 | goto tx_err; |
140 | |
141 | tx = kmem_cache_alloc(cachep: dd->vnic.txreq_cache, GFP_ATOMIC); |
142 | if (unlikely(!tx)) { |
143 | ret = -ENOMEM; |
144 | goto tx_err; |
145 | } |
146 | |
147 | tx->sdma = vnic_sdma; |
148 | tx->skb = skb; |
149 | hfi1_vnic_update_pad(pad: tx->pad, plen); |
150 | tx->plen = plen; |
151 | ret = build_vnic_tx_desc(sde, tx, pbc); |
152 | if (unlikely(ret)) |
153 | goto free_desc; |
154 | |
155 | ret = sdma_send_txreq(sde, wait: iowait_get_ib_work(w: &vnic_sdma->wait), |
156 | tx: &tx->txreq, pkts_sent: vnic_sdma->pkts_sent); |
157 | /* When -ECOMM, sdma callback will be called with ABORT status */ |
158 | if (unlikely(ret && unlikely(ret != -ECOMM))) |
159 | goto free_desc; |
160 | |
161 | if (!ret) { |
162 | vnic_sdma->pkts_sent = true; |
163 | iowait_starve_clear(pkts_sent: vnic_sdma->pkts_sent, w: &vnic_sdma->wait); |
164 | } |
165 | return ret; |
166 | |
167 | free_desc: |
168 | sdma_txclean(dd, tx: &tx->txreq); |
169 | kmem_cache_free(s: dd->vnic.txreq_cache, objp: tx); |
170 | tx_err: |
171 | if (ret != -EBUSY) |
172 | dev_kfree_skb_any(skb); |
173 | else |
174 | vnic_sdma->pkts_sent = false; |
175 | return ret; |
176 | } |
177 | |
178 | /* |
179 | * hfi1_vnic_sdma_sleep - vnic sdma sleep function |
180 | * |
181 | * This function gets called from sdma_send_txreq() when there are not enough |
182 | * sdma descriptors available to send the packet. It adds Tx queue's wait |
183 | * structure to sdma engine's dmawait list to be woken up when descriptors |
184 | * become available. |
185 | */ |
186 | static int hfi1_vnic_sdma_sleep(struct sdma_engine *sde, |
187 | struct iowait_work *wait, |
188 | struct sdma_txreq *txreq, |
189 | uint seq, |
190 | bool pkts_sent) |
191 | { |
192 | struct hfi1_vnic_sdma *vnic_sdma = |
193 | container_of(wait->iow, struct hfi1_vnic_sdma, wait); |
194 | |
195 | write_seqlock(sl: &sde->waitlock); |
196 | if (sdma_progress(sde, seq, tx: txreq)) { |
197 | write_sequnlock(sl: &sde->waitlock); |
198 | return -EAGAIN; |
199 | } |
200 | |
201 | vnic_sdma->state = HFI1_VNIC_SDMA_Q_DEFERRED; |
202 | if (list_empty(head: &vnic_sdma->wait.list)) { |
203 | iowait_get_priority(w: wait->iow); |
204 | iowait_queue(pkts_sent, w: wait->iow, wait_head: &sde->dmawait); |
205 | } |
206 | write_sequnlock(sl: &sde->waitlock); |
207 | return -EBUSY; |
208 | } |
209 | |
210 | /* |
211 | * hfi1_vnic_sdma_wakeup - vnic sdma wakeup function |
212 | * |
213 | * This function gets called when SDMA descriptors becomes available and Tx |
214 | * queue's wait structure was previously added to sdma engine's dmawait list. |
215 | * It notifies the upper driver about Tx queue wakeup. |
216 | */ |
217 | static void hfi1_vnic_sdma_wakeup(struct iowait *wait, int reason) |
218 | { |
219 | struct hfi1_vnic_sdma *vnic_sdma = |
220 | container_of(wait, struct hfi1_vnic_sdma, wait); |
221 | struct hfi1_vnic_vport_info *vinfo = vnic_sdma->vinfo; |
222 | |
223 | vnic_sdma->state = HFI1_VNIC_SDMA_Q_ACTIVE; |
224 | if (__netif_subqueue_stopped(dev: vinfo->netdev, queue_index: vnic_sdma->q_idx)) |
225 | netif_wake_subqueue(dev: vinfo->netdev, queue_index: vnic_sdma->q_idx); |
226 | }; |
227 | |
228 | inline bool hfi1_vnic_sdma_write_avail(struct hfi1_vnic_vport_info *vinfo, |
229 | u8 q_idx) |
230 | { |
231 | struct hfi1_vnic_sdma *vnic_sdma = &vinfo->sdma[q_idx]; |
232 | |
233 | return (READ_ONCE(vnic_sdma->state) == HFI1_VNIC_SDMA_Q_ACTIVE); |
234 | } |
235 | |
236 | void hfi1_vnic_sdma_init(struct hfi1_vnic_vport_info *vinfo) |
237 | { |
238 | int i; |
239 | |
240 | for (i = 0; i < vinfo->num_tx_q; i++) { |
241 | struct hfi1_vnic_sdma *vnic_sdma = &vinfo->sdma[i]; |
242 | |
243 | iowait_init(wait: &vnic_sdma->wait, tx_limit: 0, NULL, NULL, |
244 | sleep: hfi1_vnic_sdma_sleep, |
245 | wakeup: hfi1_vnic_sdma_wakeup, NULL, NULL); |
246 | vnic_sdma->sde = &vinfo->dd->per_sdma[i]; |
247 | vnic_sdma->dd = vinfo->dd; |
248 | vnic_sdma->vinfo = vinfo; |
249 | vnic_sdma->q_idx = i; |
250 | vnic_sdma->state = HFI1_VNIC_SDMA_Q_ACTIVE; |
251 | |
252 | /* Add a free descriptor watermark for wakeups */ |
253 | if (vnic_sdma->sde->descq_cnt > HFI1_VNIC_SDMA_DESC_WTRMRK) { |
254 | struct iowait_work *work; |
255 | |
256 | INIT_LIST_HEAD(list: &vnic_sdma->stx.list); |
257 | vnic_sdma->stx.num_desc = HFI1_VNIC_SDMA_DESC_WTRMRK; |
258 | work = iowait_get_ib_work(w: &vnic_sdma->wait); |
259 | list_add_tail(new: &vnic_sdma->stx.list, head: &work->tx_head); |
260 | } |
261 | } |
262 | } |
263 | |
264 | int hfi1_vnic_txreq_init(struct hfi1_devdata *dd) |
265 | { |
266 | char buf[HFI1_VNIC_TXREQ_NAME_LEN]; |
267 | |
268 | snprintf(buf, size: sizeof(buf), fmt: "hfi1_%u_vnic_txreq_cache" , dd->unit); |
269 | dd->vnic.txreq_cache = kmem_cache_create(name: buf, |
270 | size: sizeof(struct vnic_txreq), |
271 | align: 0, SLAB_HWCACHE_ALIGN, |
272 | NULL); |
273 | if (!dd->vnic.txreq_cache) |
274 | return -ENOMEM; |
275 | return 0; |
276 | } |
277 | |
278 | void hfi1_vnic_txreq_deinit(struct hfi1_devdata *dd) |
279 | { |
280 | kmem_cache_destroy(s: dd->vnic.txreq_cache); |
281 | dd->vnic.txreq_cache = NULL; |
282 | } |
283 | |