1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * vDPA bridge driver for Alibaba ENI(Elastic Network Interface)
4 *
5 * Copyright (c) 2021, Alibaba Inc. All rights reserved.
6 * Author: Wu Zongyong <wuzongyong@linux.alibaba.com>
7 *
8 */
9
10#include "linux/bits.h"
11#include <linux/interrupt.h>
12#include <linux/module.h>
13#include <linux/pci.h>
14#include <linux/vdpa.h>
15#include <linux/virtio.h>
16#include <linux/virtio_config.h>
17#include <linux/virtio_ring.h>
18#include <linux/virtio_pci.h>
19#include <linux/virtio_pci_legacy.h>
20#include <uapi/linux/virtio_net.h>
21
22#define ENI_MSIX_NAME_SIZE 256
23
24#define ENI_ERR(pdev, fmt, ...) \
25 dev_err(&pdev->dev, "%s"fmt, "eni_vdpa: ", ##__VA_ARGS__)
26#define ENI_DBG(pdev, fmt, ...) \
27 dev_dbg(&pdev->dev, "%s"fmt, "eni_vdpa: ", ##__VA_ARGS__)
28#define ENI_INFO(pdev, fmt, ...) \
29 dev_info(&pdev->dev, "%s"fmt, "eni_vdpa: ", ##__VA_ARGS__)
30
31struct eni_vring {
32 void __iomem *notify;
33 char msix_name[ENI_MSIX_NAME_SIZE];
34 struct vdpa_callback cb;
35 int irq;
36};
37
38struct eni_vdpa {
39 struct vdpa_device vdpa;
40 struct virtio_pci_legacy_device ldev;
41 struct eni_vring *vring;
42 struct vdpa_callback config_cb;
43 char msix_name[ENI_MSIX_NAME_SIZE];
44 int config_irq;
45 int queues;
46 int vectors;
47};
48
49static struct eni_vdpa *vdpa_to_eni(struct vdpa_device *vdpa)
50{
51 return container_of(vdpa, struct eni_vdpa, vdpa);
52}
53
54static struct virtio_pci_legacy_device *vdpa_to_ldev(struct vdpa_device *vdpa)
55{
56 struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
57
58 return &eni_vdpa->ldev;
59}
60
61static u64 eni_vdpa_get_device_features(struct vdpa_device *vdpa)
62{
63 struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
64 u64 features = vp_legacy_get_features(ldev);
65
66 features |= BIT_ULL(VIRTIO_F_ACCESS_PLATFORM);
67 features |= BIT_ULL(VIRTIO_F_ORDER_PLATFORM);
68
69 return features;
70}
71
72static int eni_vdpa_set_driver_features(struct vdpa_device *vdpa, u64 features)
73{
74 struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
75
76 if (!(features & BIT_ULL(VIRTIO_NET_F_MRG_RXBUF)) && features) {
77 ENI_ERR(ldev->pci_dev,
78 "VIRTIO_NET_F_MRG_RXBUF is not negotiated\n");
79 return -EINVAL;
80 }
81
82 vp_legacy_set_features(ldev, features: (u32)features);
83
84 return 0;
85}
86
87static u64 eni_vdpa_get_driver_features(struct vdpa_device *vdpa)
88{
89 struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
90
91 return vp_legacy_get_driver_features(ldev);
92}
93
94static u8 eni_vdpa_get_status(struct vdpa_device *vdpa)
95{
96 struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
97
98 return vp_legacy_get_status(ldev);
99}
100
101static int eni_vdpa_get_vq_irq(struct vdpa_device *vdpa, u16 idx)
102{
103 struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
104 int irq = eni_vdpa->vring[idx].irq;
105
106 if (irq == VIRTIO_MSI_NO_VECTOR)
107 return -EINVAL;
108
109 return irq;
110}
111
112static void eni_vdpa_free_irq(struct eni_vdpa *eni_vdpa)
113{
114 struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
115 struct pci_dev *pdev = ldev->pci_dev;
116 int i;
117
118 for (i = 0; i < eni_vdpa->queues; i++) {
119 if (eni_vdpa->vring[i].irq != VIRTIO_MSI_NO_VECTOR) {
120 vp_legacy_queue_vector(ldev, idx: i, VIRTIO_MSI_NO_VECTOR);
121 devm_free_irq(dev: &pdev->dev, irq: eni_vdpa->vring[i].irq,
122 dev_id: &eni_vdpa->vring[i]);
123 eni_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
124 }
125 }
126
127 if (eni_vdpa->config_irq != VIRTIO_MSI_NO_VECTOR) {
128 vp_legacy_config_vector(ldev, VIRTIO_MSI_NO_VECTOR);
129 devm_free_irq(dev: &pdev->dev, irq: eni_vdpa->config_irq, dev_id: eni_vdpa);
130 eni_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
131 }
132
133 if (eni_vdpa->vectors) {
134 pci_free_irq_vectors(dev: pdev);
135 eni_vdpa->vectors = 0;
136 }
137}
138
139static irqreturn_t eni_vdpa_vq_handler(int irq, void *arg)
140{
141 struct eni_vring *vring = arg;
142
143 if (vring->cb.callback)
144 return vring->cb.callback(vring->cb.private);
145
146 return IRQ_HANDLED;
147}
148
149static irqreturn_t eni_vdpa_config_handler(int irq, void *arg)
150{
151 struct eni_vdpa *eni_vdpa = arg;
152
153 if (eni_vdpa->config_cb.callback)
154 return eni_vdpa->config_cb.callback(eni_vdpa->config_cb.private);
155
156 return IRQ_HANDLED;
157}
158
159static int eni_vdpa_request_irq(struct eni_vdpa *eni_vdpa)
160{
161 struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
162 struct pci_dev *pdev = ldev->pci_dev;
163 int i, ret, irq;
164 int queues = eni_vdpa->queues;
165 int vectors = queues + 1;
166
167 ret = pci_alloc_irq_vectors(dev: pdev, min_vecs: vectors, max_vecs: vectors, PCI_IRQ_MSIX);
168 if (ret != vectors) {
169 ENI_ERR(pdev,
170 "failed to allocate irq vectors want %d but %d\n",
171 vectors, ret);
172 return ret;
173 }
174
175 eni_vdpa->vectors = vectors;
176
177 for (i = 0; i < queues; i++) {
178 snprintf(buf: eni_vdpa->vring[i].msix_name, ENI_MSIX_NAME_SIZE,
179 fmt: "eni-vdpa[%s]-%d\n", pci_name(pdev), i);
180 irq = pci_irq_vector(dev: pdev, nr: i);
181 ret = devm_request_irq(dev: &pdev->dev, irq,
182 handler: eni_vdpa_vq_handler,
183 irqflags: 0, devname: eni_vdpa->vring[i].msix_name,
184 dev_id: &eni_vdpa->vring[i]);
185 if (ret) {
186 ENI_ERR(pdev, "failed to request irq for vq %d\n", i);
187 goto err;
188 }
189 vp_legacy_queue_vector(ldev, idx: i, vector: i);
190 eni_vdpa->vring[i].irq = irq;
191 }
192
193 snprintf(buf: eni_vdpa->msix_name, ENI_MSIX_NAME_SIZE, fmt: "eni-vdpa[%s]-config\n",
194 pci_name(pdev));
195 irq = pci_irq_vector(dev: pdev, nr: queues);
196 ret = devm_request_irq(dev: &pdev->dev, irq, handler: eni_vdpa_config_handler, irqflags: 0,
197 devname: eni_vdpa->msix_name, dev_id: eni_vdpa);
198 if (ret) {
199 ENI_ERR(pdev, "failed to request irq for config vq %d\n", i);
200 goto err;
201 }
202 vp_legacy_config_vector(ldev, vector: queues);
203 eni_vdpa->config_irq = irq;
204
205 return 0;
206err:
207 eni_vdpa_free_irq(eni_vdpa);
208 return ret;
209}
210
211static void eni_vdpa_set_status(struct vdpa_device *vdpa, u8 status)
212{
213 struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
214 struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
215 u8 s = eni_vdpa_get_status(vdpa);
216
217 if (status & VIRTIO_CONFIG_S_DRIVER_OK &&
218 !(s & VIRTIO_CONFIG_S_DRIVER_OK)) {
219 eni_vdpa_request_irq(eni_vdpa);
220 }
221
222 vp_legacy_set_status(ldev, status);
223
224 if (!(status & VIRTIO_CONFIG_S_DRIVER_OK) &&
225 (s & VIRTIO_CONFIG_S_DRIVER_OK))
226 eni_vdpa_free_irq(eni_vdpa);
227}
228
229static int eni_vdpa_reset(struct vdpa_device *vdpa)
230{
231 struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
232 struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
233 u8 s = eni_vdpa_get_status(vdpa);
234
235 vp_legacy_set_status(ldev, status: 0);
236
237 if (s & VIRTIO_CONFIG_S_DRIVER_OK)
238 eni_vdpa_free_irq(eni_vdpa);
239
240 return 0;
241}
242
243static u16 eni_vdpa_get_vq_num_max(struct vdpa_device *vdpa)
244{
245 struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
246
247 return vp_legacy_get_queue_size(ldev, idx: 0);
248}
249
250static u16 eni_vdpa_get_vq_num_min(struct vdpa_device *vdpa)
251{
252 struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
253
254 return vp_legacy_get_queue_size(ldev, idx: 0);
255}
256
257static u16 eni_vdpa_get_vq_size(struct vdpa_device *vdpa, u16 qid)
258{
259 struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
260
261 return vp_legacy_get_queue_size(ldev, idx: qid);
262}
263
264static int eni_vdpa_get_vq_state(struct vdpa_device *vdpa, u16 qid,
265 struct vdpa_vq_state *state)
266{
267 return -EOPNOTSUPP;
268}
269
270static int eni_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 qid,
271 const struct vdpa_vq_state *state)
272{
273 struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
274 const struct vdpa_vq_state_split *split = &state->split;
275
276 /* ENI is build upon virtio-pci specfication which not support
277 * to set state of virtqueue. But if the state is equal to the
278 * device initial state by chance, we can let it go.
279 */
280 if (!vp_legacy_get_queue_enable(ldev, idx: qid)
281 && split->avail_index == 0)
282 return 0;
283
284 return -EOPNOTSUPP;
285}
286
287
288static void eni_vdpa_set_vq_cb(struct vdpa_device *vdpa, u16 qid,
289 struct vdpa_callback *cb)
290{
291 struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
292
293 eni_vdpa->vring[qid].cb = *cb;
294}
295
296static void eni_vdpa_set_vq_ready(struct vdpa_device *vdpa, u16 qid,
297 bool ready)
298{
299 struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
300
301 /* ENI is a legacy virtio-pci device. This is not supported
302 * by specification. But we can disable virtqueue by setting
303 * address to 0.
304 */
305 if (!ready)
306 vp_legacy_set_queue_address(ldev, index: qid, queue_pfn: 0);
307}
308
309static bool eni_vdpa_get_vq_ready(struct vdpa_device *vdpa, u16 qid)
310{
311 struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
312
313 return vp_legacy_get_queue_enable(ldev, idx: qid);
314}
315
316static void eni_vdpa_set_vq_num(struct vdpa_device *vdpa, u16 qid,
317 u32 num)
318{
319 struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
320 struct pci_dev *pdev = ldev->pci_dev;
321 u16 n = vp_legacy_get_queue_size(ldev, idx: qid);
322
323 /* ENI is a legacy virtio-pci device which not allow to change
324 * virtqueue size. Just report a error if someone tries to
325 * change it.
326 */
327 if (num != n)
328 ENI_ERR(pdev,
329 "not support to set vq %u fixed num %u to %u\n",
330 qid, n, num);
331}
332
333static int eni_vdpa_set_vq_address(struct vdpa_device *vdpa, u16 qid,
334 u64 desc_area, u64 driver_area,
335 u64 device_area)
336{
337 struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
338 u32 pfn = desc_area >> VIRTIO_PCI_QUEUE_ADDR_SHIFT;
339
340 vp_legacy_set_queue_address(ldev, index: qid, queue_pfn: pfn);
341
342 return 0;
343}
344
345static void eni_vdpa_kick_vq(struct vdpa_device *vdpa, u16 qid)
346{
347 struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
348
349 iowrite16(qid, eni_vdpa->vring[qid].notify);
350}
351
352static u32 eni_vdpa_get_device_id(struct vdpa_device *vdpa)
353{
354 struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
355
356 return ldev->id.device;
357}
358
359static u32 eni_vdpa_get_vendor_id(struct vdpa_device *vdpa)
360{
361 struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
362
363 return ldev->id.vendor;
364}
365
366static u32 eni_vdpa_get_vq_align(struct vdpa_device *vdpa)
367{
368 return VIRTIO_PCI_VRING_ALIGN;
369}
370
371static size_t eni_vdpa_get_config_size(struct vdpa_device *vdpa)
372{
373 return sizeof(struct virtio_net_config);
374}
375
376
377static void eni_vdpa_get_config(struct vdpa_device *vdpa,
378 unsigned int offset,
379 void *buf, unsigned int len)
380{
381 struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
382 struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
383 void __iomem *ioaddr = ldev->ioaddr +
384 VIRTIO_PCI_CONFIG_OFF(eni_vdpa->vectors) +
385 offset;
386 u8 *p = buf;
387 int i;
388
389 for (i = 0; i < len; i++)
390 *p++ = ioread8(ioaddr + i);
391}
392
393static void eni_vdpa_set_config(struct vdpa_device *vdpa,
394 unsigned int offset, const void *buf,
395 unsigned int len)
396{
397 struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
398 struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
399 void __iomem *ioaddr = ldev->ioaddr +
400 VIRTIO_PCI_CONFIG_OFF(eni_vdpa->vectors) +
401 offset;
402 const u8 *p = buf;
403 int i;
404
405 for (i = 0; i < len; i++)
406 iowrite8(*p++, ioaddr + i);
407}
408
409static void eni_vdpa_set_config_cb(struct vdpa_device *vdpa,
410 struct vdpa_callback *cb)
411{
412 struct eni_vdpa *eni_vdpa = vdpa_to_eni(vdpa);
413
414 eni_vdpa->config_cb = *cb;
415}
416
417static const struct vdpa_config_ops eni_vdpa_ops = {
418 .get_device_features = eni_vdpa_get_device_features,
419 .set_driver_features = eni_vdpa_set_driver_features,
420 .get_driver_features = eni_vdpa_get_driver_features,
421 .get_status = eni_vdpa_get_status,
422 .set_status = eni_vdpa_set_status,
423 .reset = eni_vdpa_reset,
424 .get_vq_num_max = eni_vdpa_get_vq_num_max,
425 .get_vq_num_min = eni_vdpa_get_vq_num_min,
426 .get_vq_size = eni_vdpa_get_vq_size,
427 .get_vq_state = eni_vdpa_get_vq_state,
428 .set_vq_state = eni_vdpa_set_vq_state,
429 .set_vq_cb = eni_vdpa_set_vq_cb,
430 .set_vq_ready = eni_vdpa_set_vq_ready,
431 .get_vq_ready = eni_vdpa_get_vq_ready,
432 .set_vq_num = eni_vdpa_set_vq_num,
433 .set_vq_address = eni_vdpa_set_vq_address,
434 .kick_vq = eni_vdpa_kick_vq,
435 .get_device_id = eni_vdpa_get_device_id,
436 .get_vendor_id = eni_vdpa_get_vendor_id,
437 .get_vq_align = eni_vdpa_get_vq_align,
438 .get_config_size = eni_vdpa_get_config_size,
439 .get_config = eni_vdpa_get_config,
440 .set_config = eni_vdpa_set_config,
441 .set_config_cb = eni_vdpa_set_config_cb,
442 .get_vq_irq = eni_vdpa_get_vq_irq,
443};
444
445
446static u16 eni_vdpa_get_num_queues(struct eni_vdpa *eni_vdpa)
447{
448 struct virtio_pci_legacy_device *ldev = &eni_vdpa->ldev;
449 u32 features = vp_legacy_get_features(ldev);
450 u16 num = 2;
451
452 if (features & BIT_ULL(VIRTIO_NET_F_MQ)) {
453 __virtio16 max_virtqueue_pairs;
454
455 eni_vdpa_get_config(vdpa: &eni_vdpa->vdpa,
456 offsetof(struct virtio_net_config, max_virtqueue_pairs),
457 buf: &max_virtqueue_pairs,
458 len: sizeof(max_virtqueue_pairs));
459 num = 2 * __virtio16_to_cpu(little_endian: virtio_legacy_is_little_endian(),
460 val: max_virtqueue_pairs);
461 }
462
463 if (features & BIT_ULL(VIRTIO_NET_F_CTRL_VQ))
464 num += 1;
465
466 return num;
467}
468
469static int eni_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
470{
471 struct device *dev = &pdev->dev;
472 struct eni_vdpa *eni_vdpa;
473 struct virtio_pci_legacy_device *ldev;
474 int ret, i;
475
476 ret = pcim_enable_device(pdev);
477 if (ret)
478 return ret;
479
480 eni_vdpa = vdpa_alloc_device(struct eni_vdpa, vdpa,
481 dev, &eni_vdpa_ops, 1, 1, NULL, false);
482 if (IS_ERR(ptr: eni_vdpa)) {
483 ENI_ERR(pdev, "failed to allocate vDPA structure\n");
484 return PTR_ERR(ptr: eni_vdpa);
485 }
486
487 ldev = &eni_vdpa->ldev;
488 ldev->pci_dev = pdev;
489
490 ret = vp_legacy_probe(ldev);
491 if (ret) {
492 ENI_ERR(pdev, "failed to probe legacy PCI device\n");
493 goto err;
494 }
495
496 pci_set_master(dev: pdev);
497 pci_set_drvdata(pdev, data: eni_vdpa);
498
499 eni_vdpa->vdpa.dma_dev = &pdev->dev;
500 eni_vdpa->queues = eni_vdpa_get_num_queues(eni_vdpa);
501
502 eni_vdpa->vring = devm_kcalloc(dev: &pdev->dev, n: eni_vdpa->queues,
503 size: sizeof(*eni_vdpa->vring),
504 GFP_KERNEL);
505 if (!eni_vdpa->vring) {
506 ret = -ENOMEM;
507 ENI_ERR(pdev, "failed to allocate virtqueues\n");
508 goto err_remove_vp_legacy;
509 }
510
511 for (i = 0; i < eni_vdpa->queues; i++) {
512 eni_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
513 eni_vdpa->vring[i].notify = ldev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY;
514 }
515 eni_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
516
517 ret = vdpa_register_device(vdev: &eni_vdpa->vdpa, nvqs: eni_vdpa->queues);
518 if (ret) {
519 ENI_ERR(pdev, "failed to register to vdpa bus\n");
520 goto err_remove_vp_legacy;
521 }
522
523 return 0;
524
525err_remove_vp_legacy:
526 vp_legacy_remove(ldev: &eni_vdpa->ldev);
527err:
528 put_device(dev: &eni_vdpa->vdpa.dev);
529 return ret;
530}
531
532static void eni_vdpa_remove(struct pci_dev *pdev)
533{
534 struct eni_vdpa *eni_vdpa = pci_get_drvdata(pdev);
535
536 vdpa_unregister_device(vdev: &eni_vdpa->vdpa);
537 vp_legacy_remove(ldev: &eni_vdpa->ldev);
538}
539
540static struct pci_device_id eni_pci_ids[] = {
541 { PCI_DEVICE_SUB(PCI_VENDOR_ID_REDHAT_QUMRANET,
542 VIRTIO_TRANS_ID_NET,
543 PCI_SUBVENDOR_ID_REDHAT_QUMRANET,
544 VIRTIO_ID_NET) },
545 { 0 },
546};
547
548static struct pci_driver eni_vdpa_driver = {
549 .name = "alibaba-eni-vdpa",
550 .id_table = eni_pci_ids,
551 .probe = eni_vdpa_probe,
552 .remove = eni_vdpa_remove,
553};
554
555module_pci_driver(eni_vdpa_driver);
556
557MODULE_AUTHOR("Wu Zongyong <wuzongyong@linux.alibaba.com>");
558MODULE_DESCRIPTION("Alibaba ENI vDPA driver");
559MODULE_LICENSE("GPL v2");
560

source code of linux/drivers/vdpa/alibaba/eni_vdpa.c