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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * PCI Express I/O Virtualization (IOV) support
4 * Single Root IOV 1.0
5 * Address Translation Service 1.0
6 *
7 * Copyright (C) 2009 Intel Corporation, Yu Zhao <yu.zhao@intel.com>
8 */
9
10#include <linux/pci.h>
11#include <linux/slab.h>
12#include <linux/mutex.h>
13#include <linux/export.h>
14#include <linux/string.h>
15#include <linux/delay.h>
16#include "pci.h"
17
18#define VIRTFN_ID_LEN 16
19
20int pci_iov_virtfn_bus(struct pci_dev *dev, int vf_id)
21{
22 if (!dev->is_physfn)
23 return -EINVAL;
24 return dev->bus->number + ((dev->devfn + dev->sriov->offset +
25 dev->sriov->stride * vf_id) >> 8);
26}
27
28int pci_iov_virtfn_devfn(struct pci_dev *dev, int vf_id)
29{
30 if (!dev->is_physfn)
31 return -EINVAL;
32 return (dev->devfn + dev->sriov->offset +
33 dev->sriov->stride * vf_id) & 0xff;
34}
35
36/*
37 * Per SR-IOV spec sec 3.3.10 and 3.3.11, First VF Offset and VF Stride may
38 * change when NumVFs changes.
39 *
40 * Update iov->offset and iov->stride when NumVFs is written.
41 */
42static inline void pci_iov_set_numvfs(struct pci_dev *dev, int nr_virtfn)
43{
44 struct pci_sriov *iov = dev->sriov;
45
46 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn);
47 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &iov->offset);
48 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &iov->stride);
49}
50
51/*
52 * The PF consumes one bus number. NumVFs, First VF Offset, and VF Stride
53 * determine how many additional bus numbers will be consumed by VFs.
54 *
55 * Iterate over all valid NumVFs, validate offset and stride, and calculate
56 * the maximum number of bus numbers that could ever be required.
57 */
58static int compute_max_vf_buses(struct pci_dev *dev)
59{
60 struct pci_sriov *iov = dev->sriov;
61 int nr_virtfn, busnr, rc = 0;
62
63 for (nr_virtfn = iov->total_VFs; nr_virtfn; nr_virtfn--) {
64 pci_iov_set_numvfs(dev, nr_virtfn);
65 if (!iov->offset || (nr_virtfn > 1 && !iov->stride)) {
66 rc = -EIO;
67 goto out;
68 }
69
70 busnr = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
71 if (busnr > iov->max_VF_buses)
72 iov->max_VF_buses = busnr;
73 }
74
75out:
76 pci_iov_set_numvfs(dev, 0);
77 return rc;
78}
79
80static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr)
81{
82 struct pci_bus *child;
83
84 if (bus->number == busnr)
85 return bus;
86
87 child = pci_find_bus(pci_domain_nr(bus), busnr);
88 if (child)
89 return child;
90
91 child = pci_add_new_bus(bus, NULL, busnr);
92 if (!child)
93 return NULL;
94
95 pci_bus_insert_busn_res(child, busnr, busnr);
96
97 return child;
98}
99
100static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus)
101{
102 if (physbus != virtbus && list_empty(&virtbus->devices))
103 pci_remove_bus(virtbus);
104}
105
106resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)
107{
108 if (!dev->is_physfn)
109 return 0;
110
111 return dev->sriov->barsz[resno - PCI_IOV_RESOURCES];
112}
113
114static void pci_read_vf_config_common(struct pci_dev *virtfn)
115{
116 struct pci_dev *physfn = virtfn->physfn;
117
118 /*
119 * Some config registers are the same across all associated VFs.
120 * Read them once from VF0 so we can skip reading them from the
121 * other VFs.
122 *
123 * PCIe r4.0, sec 9.3.4.1, technically doesn't require all VFs to
124 * have the same Revision ID and Subsystem ID, but we assume they
125 * do.
126 */
127 pci_read_config_dword(virtfn, PCI_CLASS_REVISION,
128 &physfn->sriov->class);
129 pci_read_config_byte(virtfn, PCI_HEADER_TYPE,
130 &physfn->sriov->hdr_type);
131 pci_read_config_word(virtfn, PCI_SUBSYSTEM_VENDOR_ID,
132 &physfn->sriov->subsystem_vendor);
133 pci_read_config_word(virtfn, PCI_SUBSYSTEM_ID,
134 &physfn->sriov->subsystem_device);
135}
136
137int pci_iov_add_virtfn(struct pci_dev *dev, int id)
138{
139 int i;
140 int rc = -ENOMEM;
141 u64 size;
142 char buf[VIRTFN_ID_LEN];
143 struct pci_dev *virtfn;
144 struct resource *res;
145 struct pci_sriov *iov = dev->sriov;
146 struct pci_bus *bus;
147
148 bus = virtfn_add_bus(dev->bus, pci_iov_virtfn_bus(dev, id));
149 if (!bus)
150 goto failed;
151
152 virtfn = pci_alloc_dev(bus);
153 if (!virtfn)
154 goto failed0;
155
156 virtfn->devfn = pci_iov_virtfn_devfn(dev, id);
157 virtfn->vendor = dev->vendor;
158 virtfn->device = iov->vf_device;
159 virtfn->is_virtfn = 1;
160 virtfn->physfn = pci_dev_get(dev);
161
162 if (id == 0)
163 pci_read_vf_config_common(virtfn);
164
165 rc = pci_setup_device(virtfn);
166 if (rc)
167 goto failed1;
168
169 virtfn->dev.parent = dev->dev.parent;
170 virtfn->multifunction = 0;
171
172 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
173 res = &dev->resource[i + PCI_IOV_RESOURCES];
174 if (!res->parent)
175 continue;
176 virtfn->resource[i].name = pci_name(virtfn);
177 virtfn->resource[i].flags = res->flags;
178 size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);
179 virtfn->resource[i].start = res->start + size * id;
180 virtfn->resource[i].end = virtfn->resource[i].start + size - 1;
181 rc = request_resource(res, &virtfn->resource[i]);
182 BUG_ON(rc);
183 }
184
185 pci_device_add(virtfn, virtfn->bus);
186
187 sprintf(buf, "virtfn%u", id);
188 rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
189 if (rc)
190 goto failed2;
191 rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");
192 if (rc)
193 goto failed3;
194
195 kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);
196
197 pci_bus_add_device(virtfn);
198
199 return 0;
200
201failed3:
202 sysfs_remove_link(&dev->dev.kobj, buf);
203failed2:
204 pci_stop_and_remove_bus_device(virtfn);
205failed1:
206 pci_dev_put(dev);
207failed0:
208 virtfn_remove_bus(dev->bus, bus);
209failed:
210
211 return rc;
212}
213
214void pci_iov_remove_virtfn(struct pci_dev *dev, int id)
215{
216 char buf[VIRTFN_ID_LEN];
217 struct pci_dev *virtfn;
218
219 virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus),
220 pci_iov_virtfn_bus(dev, id),
221 pci_iov_virtfn_devfn(dev, id));
222 if (!virtfn)
223 return;
224
225 sprintf(buf, "virtfn%u", id);
226 sysfs_remove_link(&dev->dev.kobj, buf);
227 /*
228 * pci_stop_dev() could have been called for this virtfn already,
229 * so the directory for the virtfn may have been removed before.
230 * Double check to avoid spurious sysfs warnings.
231 */
232 if (virtfn->dev.kobj.sd)
233 sysfs_remove_link(&virtfn->dev.kobj, "physfn");
234
235 pci_stop_and_remove_bus_device(virtfn);
236 virtfn_remove_bus(dev->bus, virtfn->bus);
237
238 /* balance pci_get_domain_bus_and_slot() */
239 pci_dev_put(virtfn);
240 pci_dev_put(dev);
241}
242
243static ssize_t sriov_totalvfs_show(struct device *dev,
244 struct device_attribute *attr,
245 char *buf)
246{
247 struct pci_dev *pdev = to_pci_dev(dev);
248
249 return sprintf(buf, "%u\n", pci_sriov_get_totalvfs(pdev));
250}
251
252static ssize_t sriov_numvfs_show(struct device *dev,
253 struct device_attribute *attr,
254 char *buf)
255{
256 struct pci_dev *pdev = to_pci_dev(dev);
257
258 return sprintf(buf, "%u\n", pdev->sriov->num_VFs);
259}
260
261/*
262 * num_vfs > 0; number of VFs to enable
263 * num_vfs = 0; disable all VFs
264 *
265 * Note: SRIOV spec does not allow partial VF
266 * disable, so it's all or none.
267 */
268static ssize_t sriov_numvfs_store(struct device *dev,
269 struct device_attribute *attr,
270 const char *buf, size_t count)
271{
272 struct pci_dev *pdev = to_pci_dev(dev);
273 int ret;
274 u16 num_vfs;
275
276 ret = kstrtou16(buf, 0, &num_vfs);
277 if (ret < 0)
278 return ret;
279
280 if (num_vfs > pci_sriov_get_totalvfs(pdev))
281 return -ERANGE;
282
283 device_lock(&pdev->dev);
284
285 if (num_vfs == pdev->sriov->num_VFs)
286 goto exit;
287
288 /* is PF driver loaded w/callback */
289 if (!pdev->driver || !pdev->driver->sriov_configure) {
290 pci_info(pdev, "Driver does not support SRIOV configuration via sysfs\n");
291 ret = -ENOENT;
292 goto exit;
293 }
294
295 if (num_vfs == 0) {
296 /* disable VFs */
297 ret = pdev->driver->sriov_configure(pdev, 0);
298 goto exit;
299 }
300
301 /* enable VFs */
302 if (pdev->sriov->num_VFs) {
303 pci_warn(pdev, "%d VFs already enabled. Disable before enabling %d VFs\n",
304 pdev->sriov->num_VFs, num_vfs);
305 ret = -EBUSY;
306 goto exit;
307 }
308
309 ret = pdev->driver->sriov_configure(pdev, num_vfs);
310 if (ret < 0)
311 goto exit;
312
313 if (ret != num_vfs)
314 pci_warn(pdev, "%d VFs requested; only %d enabled\n",
315 num_vfs, ret);
316
317exit:
318 device_unlock(&pdev->dev);
319
320 if (ret < 0)
321 return ret;
322
323 return count;
324}
325
326static ssize_t sriov_offset_show(struct device *dev,
327 struct device_attribute *attr,
328 char *buf)
329{
330 struct pci_dev *pdev = to_pci_dev(dev);
331
332 return sprintf(buf, "%u\n", pdev->sriov->offset);
333}
334
335static ssize_t sriov_stride_show(struct device *dev,
336 struct device_attribute *attr,
337 char *buf)
338{
339 struct pci_dev *pdev = to_pci_dev(dev);
340
341 return sprintf(buf, "%u\n", pdev->sriov->stride);
342}
343
344static ssize_t sriov_vf_device_show(struct device *dev,
345 struct device_attribute *attr,
346 char *buf)
347{
348 struct pci_dev *pdev = to_pci_dev(dev);
349
350 return sprintf(buf, "%x\n", pdev->sriov->vf_device);
351}
352
353static ssize_t sriov_drivers_autoprobe_show(struct device *dev,
354 struct device_attribute *attr,
355 char *buf)
356{
357 struct pci_dev *pdev = to_pci_dev(dev);
358
359 return sprintf(buf, "%u\n", pdev->sriov->drivers_autoprobe);
360}
361
362static ssize_t sriov_drivers_autoprobe_store(struct device *dev,
363 struct device_attribute *attr,
364 const char *buf, size_t count)
365{
366 struct pci_dev *pdev = to_pci_dev(dev);
367 bool drivers_autoprobe;
368
369 if (kstrtobool(buf, &drivers_autoprobe) < 0)
370 return -EINVAL;
371
372 pdev->sriov->drivers_autoprobe = drivers_autoprobe;
373
374 return count;
375}
376
377static DEVICE_ATTR_RO(sriov_totalvfs);
378static DEVICE_ATTR_RW(sriov_numvfs);
379static DEVICE_ATTR_RO(sriov_offset);
380static DEVICE_ATTR_RO(sriov_stride);
381static DEVICE_ATTR_RO(sriov_vf_device);
382static DEVICE_ATTR_RW(sriov_drivers_autoprobe);
383
384static struct attribute *sriov_dev_attrs[] = {
385 &dev_attr_sriov_totalvfs.attr,
386 &dev_attr_sriov_numvfs.attr,
387 &dev_attr_sriov_offset.attr,
388 &dev_attr_sriov_stride.attr,
389 &dev_attr_sriov_vf_device.attr,
390 &dev_attr_sriov_drivers_autoprobe.attr,
391 NULL,
392};
393
394static umode_t sriov_attrs_are_visible(struct kobject *kobj,
395 struct attribute *a, int n)
396{
397 struct device *dev = kobj_to_dev(kobj);
398
399 if (!dev_is_pf(dev))
400 return 0;
401
402 return a->mode;
403}
404
405const struct attribute_group sriov_dev_attr_group = {
406 .attrs = sriov_dev_attrs,
407 .is_visible = sriov_attrs_are_visible,
408};
409
410int __weak pcibios_sriov_enable(struct pci_dev *pdev, u16 num_vfs)
411{
412 return 0;
413}
414
415int __weak pcibios_sriov_disable(struct pci_dev *pdev)
416{
417 return 0;
418}
419
420static int sriov_add_vfs(struct pci_dev *dev, u16 num_vfs)
421{
422 unsigned int i;
423 int rc;
424
425 if (dev->no_vf_scan)
426 return 0;
427
428 for (i = 0; i < num_vfs; i++) {
429 rc = pci_iov_add_virtfn(dev, i);
430 if (rc)
431 goto failed;
432 }
433 return 0;
434failed:
435 while (i--)
436 pci_iov_remove_virtfn(dev, i);
437
438 return rc;
439}
440
441static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
442{
443 int rc;
444 int i;
445 int nres;
446 u16 initial;
447 struct resource *res;
448 struct pci_dev *pdev;
449 struct pci_sriov *iov = dev->sriov;
450 int bars = 0;
451 int bus;
452
453 if (!nr_virtfn)
454 return 0;
455
456 if (iov->num_VFs)
457 return -EINVAL;
458
459 pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial);
460 if (initial > iov->total_VFs ||
461 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total_VFs)))
462 return -EIO;
463
464 if (nr_virtfn < 0 || nr_virtfn > iov->total_VFs ||
465 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
466 return -EINVAL;
467
468 nres = 0;
469 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
470 bars |= (1 << (i + PCI_IOV_RESOURCES));
471 res = &dev->resource[i + PCI_IOV_RESOURCES];
472 if (res->parent)
473 nres++;
474 }
475 if (nres != iov->nres) {
476 pci_err(dev, "not enough MMIO resources for SR-IOV\n");
477 return -ENOMEM;
478 }
479
480 bus = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
481 if (bus > dev->bus->busn_res.end) {
482 pci_err(dev, "can't enable %d VFs (bus %02x out of range of %pR)\n",
483 nr_virtfn, bus, &dev->bus->busn_res);
484 return -ENOMEM;
485 }
486
487 if (pci_enable_resources(dev, bars)) {
488 pci_err(dev, "SR-IOV: IOV BARS not allocated\n");
489 return -ENOMEM;
490 }
491
492 if (iov->link != dev->devfn) {
493 pdev = pci_get_slot(dev->bus, iov->link);
494 if (!pdev)
495 return -ENODEV;
496
497 if (!pdev->is_physfn) {
498 pci_dev_put(pdev);
499 return -ENOSYS;
500 }
501
502 rc = sysfs_create_link(&dev->dev.kobj,
503 &pdev->dev.kobj, "dep_link");
504 pci_dev_put(pdev);
505 if (rc)
506 return rc;
507 }
508
509 iov->initial_VFs = initial;
510 if (nr_virtfn < initial)
511 initial = nr_virtfn;
512
513 rc = pcibios_sriov_enable(dev, initial);
514 if (rc) {
515 pci_err(dev, "failure %d from pcibios_sriov_enable()\n", rc);
516 goto err_pcibios;
517 }
518
519 pci_iov_set_numvfs(dev, nr_virtfn);
520 iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
521 pci_cfg_access_lock(dev);
522 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
523 msleep(100);
524 pci_cfg_access_unlock(dev);
525
526 rc = sriov_add_vfs(dev, initial);
527 if (rc)
528 goto err_pcibios;
529
530 kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE);
531 iov->num_VFs = nr_virtfn;
532
533 return 0;
534
535err_pcibios:
536 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
537 pci_cfg_access_lock(dev);
538 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
539 ssleep(1);
540 pci_cfg_access_unlock(dev);
541
542 pcibios_sriov_disable(dev);
543
544 if (iov->link != dev->devfn)
545 sysfs_remove_link(&dev->dev.kobj, "dep_link");
546
547 pci_iov_set_numvfs(dev, 0);
548 return rc;
549}
550
551static void sriov_del_vfs(struct pci_dev *dev)
552{
553 struct pci_sriov *iov = dev->sriov;
554 int i;
555
556 if (dev->no_vf_scan)
557 return;
558
559 for (i = 0; i < iov->num_VFs; i++)
560 pci_iov_remove_virtfn(dev, i);
561}
562
563static void sriov_disable(struct pci_dev *dev)
564{
565 struct pci_sriov *iov = dev->sriov;
566
567 if (!iov->num_VFs)
568 return;
569
570 sriov_del_vfs(dev);
571 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
572 pci_cfg_access_lock(dev);
573 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
574 ssleep(1);
575 pci_cfg_access_unlock(dev);
576
577 pcibios_sriov_disable(dev);
578
579 if (iov->link != dev->devfn)
580 sysfs_remove_link(&dev->dev.kobj, "dep_link");
581
582 iov->num_VFs = 0;
583 pci_iov_set_numvfs(dev, 0);
584}
585
586static int sriov_init(struct pci_dev *dev, int pos)
587{
588 int i, bar64;
589 int rc;
590 int nres;
591 u32 pgsz;
592 u16 ctrl, total;
593 struct pci_sriov *iov;
594 struct resource *res;
595 struct pci_dev *pdev;
596
597 pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl);
598 if (ctrl & PCI_SRIOV_CTRL_VFE) {
599 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0);
600 ssleep(1);
601 }
602
603 ctrl = 0;
604 list_for_each_entry(pdev, &dev->bus->devices, bus_list)
605 if (pdev->is_physfn)
606 goto found;
607
608 pdev = NULL;
609 if (pci_ari_enabled(dev->bus))
610 ctrl |= PCI_SRIOV_CTRL_ARI;
611
612found:
613 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl);
614
615 pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total);
616 if (!total)
617 return 0;
618
619 pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz);
620 i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0;
621 pgsz &= ~((1 << i) - 1);
622 if (!pgsz)
623 return -EIO;
624
625 pgsz &= ~(pgsz - 1);
626 pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz);
627
628 iov = kzalloc(sizeof(*iov), GFP_KERNEL);
629 if (!iov)
630 return -ENOMEM;
631
632 nres = 0;
633 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
634 res = &dev->resource[i + PCI_IOV_RESOURCES];
635 /*
636 * If it is already FIXED, don't change it, something
637 * (perhaps EA or header fixups) wants it this way.
638 */
639 if (res->flags & IORESOURCE_PCI_FIXED)
640 bar64 = (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
641 else
642 bar64 = __pci_read_base(dev, pci_bar_unknown, res,
643 pos + PCI_SRIOV_BAR + i * 4);
644 if (!res->flags)
645 continue;
646 if (resource_size(res) & (PAGE_SIZE - 1)) {
647 rc = -EIO;
648 goto failed;
649 }
650 iov->barsz[i] = resource_size(res);
651 res->end = res->start + resource_size(res) * total - 1;
652 pci_info(dev, "VF(n) BAR%d space: %pR (contains BAR%d for %d VFs)\n",
653 i, res, i, total);
654 i += bar64;
655 nres++;
656 }
657
658 iov->pos = pos;
659 iov->nres = nres;
660 iov->ctrl = ctrl;
661 iov->total_VFs = total;
662 iov->driver_max_VFs = total;
663 pci_read_config_word(dev, pos + PCI_SRIOV_VF_DID, &iov->vf_device);
664 iov->pgsz = pgsz;
665 iov->self = dev;
666 iov->drivers_autoprobe = true;
667 pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap);
668 pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link);
669 if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END)
670 iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link);
671
672 if (pdev)
673 iov->dev = pci_dev_get(pdev);
674 else
675 iov->dev = dev;
676
677 dev->sriov = iov;
678 dev->is_physfn = 1;
679 rc = compute_max_vf_buses(dev);
680 if (rc)
681 goto fail_max_buses;
682
683 return 0;
684
685fail_max_buses:
686 dev->sriov = NULL;
687 dev->is_physfn = 0;
688failed:
689 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
690 res = &dev->resource[i + PCI_IOV_RESOURCES];
691 res->flags = 0;
692 }
693
694 kfree(iov);
695 return rc;
696}
697
698static void sriov_release(struct pci_dev *dev)
699{
700 BUG_ON(dev->sriov->num_VFs);
701
702 if (dev != dev->sriov->dev)
703 pci_dev_put(dev->sriov->dev);
704
705 kfree(dev->sriov);
706 dev->sriov = NULL;
707}
708
709static void sriov_restore_state(struct pci_dev *dev)
710{
711 int i;
712 u16 ctrl;
713 struct pci_sriov *iov = dev->sriov;
714
715 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl);
716 if (ctrl & PCI_SRIOV_CTRL_VFE)
717 return;
718
719 /*
720 * Restore PCI_SRIOV_CTRL_ARI before pci_iov_set_numvfs() because
721 * it reads offset & stride, which depend on PCI_SRIOV_CTRL_ARI.
722 */
723 ctrl &= ~PCI_SRIOV_CTRL_ARI;
724 ctrl |= iov->ctrl & PCI_SRIOV_CTRL_ARI;
725 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, ctrl);
726
727 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++)
728 pci_update_resource(dev, i + PCI_IOV_RESOURCES);
729
730 pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
731 pci_iov_set_numvfs(dev, iov->num_VFs);
732 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
733 if (iov->ctrl & PCI_SRIOV_CTRL_VFE)
734 msleep(100);
735}
736
737/**
738 * pci_iov_init - initialize the IOV capability
739 * @dev: the PCI device
740 *
741 * Returns 0 on success, or negative on failure.
742 */
743int pci_iov_init(struct pci_dev *dev)
744{
745 int pos;
746
747 if (!pci_is_pcie(dev))
748 return -ENODEV;
749
750 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV);
751 if (pos)
752 return sriov_init(dev, pos);
753
754 return -ENODEV;
755}
756
757/**
758 * pci_iov_release - release resources used by the IOV capability
759 * @dev: the PCI device
760 */
761void pci_iov_release(struct pci_dev *dev)
762{
763 if (dev->is_physfn)
764 sriov_release(dev);
765}
766
767/**
768 * pci_iov_remove - clean up SR-IOV state after PF driver is detached
769 * @dev: the PCI device
770 */
771void pci_iov_remove(struct pci_dev *dev)
772{
773 struct pci_sriov *iov = dev->sriov;
774
775 if (!dev->is_physfn)
776 return;
777
778 iov->driver_max_VFs = iov->total_VFs;
779 if (iov->num_VFs)
780 pci_warn(dev, "driver left SR-IOV enabled after remove\n");
781}
782
783/**
784 * pci_iov_update_resource - update a VF BAR
785 * @dev: the PCI device
786 * @resno: the resource number
787 *
788 * Update a VF BAR in the SR-IOV capability of a PF.
789 */
790void pci_iov_update_resource(struct pci_dev *dev, int resno)
791{
792 struct pci_sriov *iov = dev->is_physfn ? dev->sriov : NULL;
793 struct resource *res = dev->resource + resno;
794 int vf_bar = resno - PCI_IOV_RESOURCES;
795 struct pci_bus_region region;
796 u16 cmd;
797 u32 new;
798 int reg;
799
800 /*
801 * The generic pci_restore_bars() path calls this for all devices,
802 * including VFs and non-SR-IOV devices. If this is not a PF, we
803 * have nothing to do.
804 */
805 if (!iov)
806 return;
807
808 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &cmd);
809 if ((cmd & PCI_SRIOV_CTRL_VFE) && (cmd & PCI_SRIOV_CTRL_MSE)) {
810 dev_WARN(&dev->dev, "can't update enabled VF BAR%d %pR\n",
811 vf_bar, res);
812 return;
813 }
814
815 /*
816 * Ignore unimplemented BARs, unused resource slots for 64-bit
817 * BARs, and non-movable resources, e.g., those described via
818 * Enhanced Allocation.
819 */
820 if (!res->flags)
821 return;
822
823 if (res->flags & IORESOURCE_UNSET)
824 return;
825
826 if (res->flags & IORESOURCE_PCI_FIXED)
827 return;
828
829 pcibios_resource_to_bus(dev->bus, ®ion, res);
830 new = region.start;
831 new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK;
832
833 reg = iov->pos + PCI_SRIOV_BAR + 4 * vf_bar;
834 pci_write_config_dword(dev, reg, new);
835 if (res->flags & IORESOURCE_MEM_64) {
836 new = region.start >> 16 >> 16;
837 pci_write_config_dword(dev, reg + 4, new);
838 }
839}
840
841resource_size_t __weak pcibios_iov_resource_alignment(struct pci_dev *dev,
842 int resno)
843{
844 return pci_iov_resource_size(dev, resno);
845}
846
847/**
848 * pci_sriov_resource_alignment - get resource alignment for VF BAR
849 * @dev: the PCI device
850 * @resno: the resource number
851 *
852 * Returns the alignment of the VF BAR found in the SR-IOV capability.
853 * This is not the same as the resource size which is defined as
854 * the VF BAR size multiplied by the number of VFs. The alignment
855 * is just the VF BAR size.
856 */
857resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno)
858{
859 return pcibios_iov_resource_alignment(dev, resno);
860}
861
862/**
863 * pci_restore_iov_state - restore the state of the IOV capability
864 * @dev: the PCI device
865 */
866void pci_restore_iov_state(struct pci_dev *dev)
867{
868 if (dev->is_physfn)
869 sriov_restore_state(dev);
870}
871
872/**
873 * pci_vf_drivers_autoprobe - set PF property drivers_autoprobe for VFs
874 * @dev: the PCI device
875 * @auto_probe: set VF drivers auto probe flag
876 */
877void pci_vf_drivers_autoprobe(struct pci_dev *dev, bool auto_probe)
878{
879 if (dev->is_physfn)
880 dev->sriov->drivers_autoprobe = auto_probe;
881}
882
883/**
884 * pci_iov_bus_range - find bus range used by Virtual Function
885 * @bus: the PCI bus
886 *
887 * Returns max number of buses (exclude current one) used by Virtual
888 * Functions.
889 */
890int pci_iov_bus_range(struct pci_bus *bus)
891{
892 int max = 0;
893 struct pci_dev *dev;
894
895 list_for_each_entry(dev, &bus->devices, bus_list) {
896 if (!dev->is_physfn)
897 continue;
898 if (dev->sriov->max_VF_buses > max)
899 max = dev->sriov->max_VF_buses;
900 }
901
902 return max ? max - bus->number : 0;
903}
904
905/**
906 * pci_enable_sriov - enable the SR-IOV capability
907 * @dev: the PCI device
908 * @nr_virtfn: number of virtual functions to enable
909 *
910 * Returns 0 on success, or negative on failure.
911 */
912int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
913{
914 might_sleep();
915
916 if (!dev->is_physfn)
917 return -ENOSYS;
918
919 return sriov_enable(dev, nr_virtfn);
920}
921EXPORT_SYMBOL_GPL(pci_enable_sriov);
922
923/**
924 * pci_disable_sriov - disable the SR-IOV capability
925 * @dev: the PCI device
926 */
927void pci_disable_sriov(struct pci_dev *dev)
928{
929 might_sleep();
930
931 if (!dev->is_physfn)
932 return;
933
934 sriov_disable(dev);
935}
936EXPORT_SYMBOL_GPL(pci_disable_sriov);
937
938/**
939 * pci_num_vf - return number of VFs associated with a PF device_release_driver
940 * @dev: the PCI device
941 *
942 * Returns number of VFs, or 0 if SR-IOV is not enabled.
943 */
944int pci_num_vf(struct pci_dev *dev)
945{
946 if (!dev->is_physfn)
947 return 0;
948
949 return dev->sriov->num_VFs;
950}
951EXPORT_SYMBOL_GPL(pci_num_vf);
952
953/**
954 * pci_vfs_assigned - returns number of VFs are assigned to a guest
955 * @dev: the PCI device
956 *
957 * Returns number of VFs belonging to this device that are assigned to a guest.
958 * If device is not a physical function returns 0.
959 */
960int pci_vfs_assigned(struct pci_dev *dev)
961{
962 struct pci_dev *vfdev;
963 unsigned int vfs_assigned = 0;
964 unsigned short dev_id;
965
966 /* only search if we are a PF */
967 if (!dev->is_physfn)
968 return 0;
969
970 /*
971 * determine the device ID for the VFs, the vendor ID will be the
972 * same as the PF so there is no need to check for that one
973 */
974 dev_id = dev->sriov->vf_device;
975
976 /* loop through all the VFs to see if we own any that are assigned */
977 vfdev = pci_get_device(dev->vendor, dev_id, NULL);
978 while (vfdev) {
979 /*
980 * It is considered assigned if it is a virtual function with
981 * our dev as the physical function and the assigned bit is set
982 */
983 if (vfdev->is_virtfn && (vfdev->physfn == dev) &&
984 pci_is_dev_assigned(vfdev))
985 vfs_assigned++;
986
987 vfdev = pci_get_device(dev->vendor, dev_id, vfdev);
988 }
989
990 return vfs_assigned;
991}
992EXPORT_SYMBOL_GPL(pci_vfs_assigned);
993
994/**
995 * pci_sriov_set_totalvfs -- reduce the TotalVFs available
996 * @dev: the PCI PF device
997 * @numvfs: number that should be used for TotalVFs supported
998 *
999 * Should be called from PF driver's probe routine with
1000 * device's mutex held.
1001 *
1002 * Returns 0 if PF is an SRIOV-capable device and
1003 * value of numvfs valid. If not a PF return -ENOSYS;
1004 * if numvfs is invalid return -EINVAL;
1005 * if VFs already enabled, return -EBUSY.
1006 */
1007int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs)
1008{
1009 if (!dev->is_physfn)
1010 return -ENOSYS;
1011
1012 if (numvfs > dev->sriov->total_VFs)
1013 return -EINVAL;
1014
1015 /* Shouldn't change if VFs already enabled */
1016 if (dev->sriov->ctrl & PCI_SRIOV_CTRL_VFE)
1017 return -EBUSY;
1018
1019 dev->sriov->driver_max_VFs = numvfs;
1020 return 0;
1021}
1022EXPORT_SYMBOL_GPL(pci_sriov_set_totalvfs);
1023
1024/**
1025 * pci_sriov_get_totalvfs -- get total VFs supported on this device
1026 * @dev: the PCI PF device
1027 *
1028 * For a PCIe device with SRIOV support, return the PCIe
1029 * SRIOV capability value of TotalVFs or the value of driver_max_VFs
1030 * if the driver reduced it. Otherwise 0.
1031 */
1032int pci_sriov_get_totalvfs(struct pci_dev *dev)
1033{
1034 if (!dev->is_physfn)
1035 return 0;
1036
1037 return dev->sriov->driver_max_VFs;
1038}
1039EXPORT_SYMBOL_GPL(pci_sriov_get_totalvfs);
1040
1041/**
1042 * pci_sriov_configure_simple - helper to configure SR-IOV
1043 * @dev: the PCI device
1044 * @nr_virtfn: number of virtual functions to enable, 0 to disable
1045 *
1046 * Enable or disable SR-IOV for devices that don't require any PF setup
1047 * before enabling SR-IOV. Return value is negative on error, or number of
1048 * VFs allocated on success.
1049 */
1050int pci_sriov_configure_simple(struct pci_dev *dev, int nr_virtfn)
1051{
1052 int rc;
1053
1054 might_sleep();
1055
1056 if (!dev->is_physfn)
1057 return -ENODEV;
1058
1059 if (pci_vfs_assigned(dev)) {
1060 pci_warn(dev, "Cannot modify SR-IOV while VFs are assigned\n");
1061 return -EPERM;
1062 }
1063
1064 if (nr_virtfn == 0) {
1065 sriov_disable(dev);
1066 return 0;
1067 }
1068
1069 rc = sriov_enable(dev, nr_virtfn);
1070 if (rc < 0)
1071 return rc;
1072
1073 return nr_virtfn;
1074}
1075EXPORT_SYMBOL_GPL(pci_sriov_configure_simple);
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * PCI Express I/O Virtualization (IOV) support
4 * Single Root IOV 1.0
5 * Address Translation Service 1.0
6 *
7 * Copyright (C) 2009 Intel Corporation, Yu Zhao <yu.zhao@intel.com>
8 */
9
10#include <linux/pci.h>
11#include <linux/slab.h>
12#include <linux/export.h>
13#include <linux/string.h>
14#include <linux/delay.h>
15#include "pci.h"
16
17#define VIRTFN_ID_LEN 16
18
19int pci_iov_virtfn_bus(struct pci_dev *dev, int vf_id)
20{
21 if (!dev->is_physfn)
22 return -EINVAL;
23 return dev->bus->number + ((dev->devfn + dev->sriov->offset +
24 dev->sriov->stride * vf_id) >> 8);
25}
26
27int pci_iov_virtfn_devfn(struct pci_dev *dev, int vf_id)
28{
29 if (!dev->is_physfn)
30 return -EINVAL;
31 return (dev->devfn + dev->sriov->offset +
32 dev->sriov->stride * vf_id) & 0xff;
33}
34
35/*
36 * Per SR-IOV spec sec 3.3.10 and 3.3.11, First VF Offset and VF Stride may
37 * change when NumVFs changes.
38 *
39 * Update iov->offset and iov->stride when NumVFs is written.
40 */
41static inline void pci_iov_set_numvfs(struct pci_dev *dev, int nr_virtfn)
42{
43 struct pci_sriov *iov = dev->sriov;
44
45 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn);
46 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &iov->offset);
47 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &iov->stride);
48}
49
50/*
51 * The PF consumes one bus number. NumVFs, First VF Offset, and VF Stride
52 * determine how many additional bus numbers will be consumed by VFs.
53 *
54 * Iterate over all valid NumVFs, validate offset and stride, and calculate
55 * the maximum number of bus numbers that could ever be required.
56 */
57static int compute_max_vf_buses(struct pci_dev *dev)
58{
59 struct pci_sriov *iov = dev->sriov;
60 int nr_virtfn, busnr, rc = 0;
61
62 for (nr_virtfn = iov->total_VFs; nr_virtfn; nr_virtfn--) {
63 pci_iov_set_numvfs(dev, nr_virtfn);
64 if (!iov->offset || (nr_virtfn > 1 && !iov->stride)) {
65 rc = -EIO;
66 goto out;
67 }
68
69 busnr = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
70 if (busnr > iov->max_VF_buses)
71 iov->max_VF_buses = busnr;
72 }
73
74out:
75 pci_iov_set_numvfs(dev, 0);
76 return rc;
77}
78
79static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr)
80{
81 struct pci_bus *child;
82
83 if (bus->number == busnr)
84 return bus;
85
86 child = pci_find_bus(pci_domain_nr(bus), busnr);
87 if (child)
88 return child;
89
90 child = pci_add_new_bus(bus, NULL, busnr);
91 if (!child)
92 return NULL;
93
94 pci_bus_insert_busn_res(child, busnr, busnr);
95
96 return child;
97}
98
99static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus)
100{
101 if (physbus != virtbus && list_empty(&virtbus->devices))
102 pci_remove_bus(virtbus);
103}
104
105resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)
106{
107 if (!dev->is_physfn)
108 return 0;
109
110 return dev->sriov->barsz[resno - PCI_IOV_RESOURCES];
111}
112
113static void pci_read_vf_config_common(struct pci_dev *virtfn)
114{
115 struct pci_dev *physfn = virtfn->physfn;
116
117 /*
118 * Some config registers are the same across all associated VFs.
119 * Read them once from VF0 so we can skip reading them from the
120 * other VFs.
121 *
122 * PCIe r4.0, sec 9.3.4.1, technically doesn't require all VFs to
123 * have the same Revision ID and Subsystem ID, but we assume they
124 * do.
125 */
126 pci_read_config_dword(virtfn, PCI_CLASS_REVISION,
127 &physfn->sriov->class);
128 pci_read_config_byte(virtfn, PCI_HEADER_TYPE,
129 &physfn->sriov->hdr_type);
130 pci_read_config_word(virtfn, PCI_SUBSYSTEM_VENDOR_ID,
131 &physfn->sriov->subsystem_vendor);
132 pci_read_config_word(virtfn, PCI_SUBSYSTEM_ID,
133 &physfn->sriov->subsystem_device);
134}
135
136int pci_iov_sysfs_link(struct pci_dev *dev,
137 struct pci_dev *virtfn, int id)
138{
139 char buf[VIRTFN_ID_LEN];
140 int rc;
141
142 sprintf(buf, "virtfn%u", id);
143 rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
144 if (rc)
145 goto failed;
146 rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");
147 if (rc)
148 goto failed1;
149
150 kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);
151
152 return 0;
153
154failed1:
155 sysfs_remove_link(&dev->dev.kobj, buf);
156failed:
157 return rc;
158}
159
160int pci_iov_add_virtfn(struct pci_dev *dev, int id)
161{
162 int i;
163 int rc = -ENOMEM;
164 u64 size;
165 struct pci_dev *virtfn;
166 struct resource *res;
167 struct pci_sriov *iov = dev->sriov;
168 struct pci_bus *bus;
169
170 bus = virtfn_add_bus(dev->bus, pci_iov_virtfn_bus(dev, id));
171 if (!bus)
172 goto failed;
173
174 virtfn = pci_alloc_dev(bus);
175 if (!virtfn)
176 goto failed0;
177
178 virtfn->devfn = pci_iov_virtfn_devfn(dev, id);
179 virtfn->vendor = dev->vendor;
180 virtfn->device = iov->vf_device;
181 virtfn->is_virtfn = 1;
182 virtfn->physfn = pci_dev_get(dev);
183
184 if (id == 0)
185 pci_read_vf_config_common(virtfn);
186
187 rc = pci_setup_device(virtfn);
188 if (rc)
189 goto failed1;
190
191 virtfn->dev.parent = dev->dev.parent;
192 virtfn->multifunction = 0;
193
194 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
195 res = &dev->resource[i + PCI_IOV_RESOURCES];
196 if (!res->parent)
197 continue;
198 virtfn->resource[i].name = pci_name(virtfn);
199 virtfn->resource[i].flags = res->flags;
200 size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);
201 virtfn->resource[i].start = res->start + size * id;
202 virtfn->resource[i].end = virtfn->resource[i].start + size - 1;
203 rc = request_resource(res, &virtfn->resource[i]);
204 BUG_ON(rc);
205 }
206
207 pci_device_add(virtfn, virtfn->bus);
208 rc = pci_iov_sysfs_link(dev, virtfn, id);
209 if (rc)
210 goto failed1;
211
212 pci_bus_add_device(virtfn);
213
214 return 0;
215
216failed1:
217 pci_stop_and_remove_bus_device(virtfn);
218 pci_dev_put(dev);
219failed0:
220 virtfn_remove_bus(dev->bus, bus);
221failed:
222
223 return rc;
224}
225
226void pci_iov_remove_virtfn(struct pci_dev *dev, int id)
227{
228 char buf[VIRTFN_ID_LEN];
229 struct pci_dev *virtfn;
230
231 virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus),
232 pci_iov_virtfn_bus(dev, id),
233 pci_iov_virtfn_devfn(dev, id));
234 if (!virtfn)
235 return;
236
237 sprintf(buf, "virtfn%u", id);
238 sysfs_remove_link(&dev->dev.kobj, buf);
239 /*
240 * pci_stop_dev() could have been called for this virtfn already,
241 * so the directory for the virtfn may have been removed before.
242 * Double check to avoid spurious sysfs warnings.
243 */
244 if (virtfn->dev.kobj.sd)
245 sysfs_remove_link(&virtfn->dev.kobj, "physfn");
246
247 pci_stop_and_remove_bus_device(virtfn);
248 virtfn_remove_bus(dev->bus, virtfn->bus);
249
250 /* balance pci_get_domain_bus_and_slot() */
251 pci_dev_put(virtfn);
252 pci_dev_put(dev);
253}
254
255static ssize_t sriov_totalvfs_show(struct device *dev,
256 struct device_attribute *attr,
257 char *buf)
258{
259 struct pci_dev *pdev = to_pci_dev(dev);
260
261 return sprintf(buf, "%u\n", pci_sriov_get_totalvfs(pdev));
262}
263
264static ssize_t sriov_numvfs_show(struct device *dev,
265 struct device_attribute *attr,
266 char *buf)
267{
268 struct pci_dev *pdev = to_pci_dev(dev);
269 u16 num_vfs;
270
271 /* Serialize vs sriov_numvfs_store() so readers see valid num_VFs */
272 device_lock(&pdev->dev);
273 num_vfs = pdev->sriov->num_VFs;
274 device_unlock(&pdev->dev);
275
276 return sprintf(buf, "%u\n", num_vfs);
277}
278
279/*
280 * num_vfs > 0; number of VFs to enable
281 * num_vfs = 0; disable all VFs
282 *
283 * Note: SRIOV spec does not allow partial VF
284 * disable, so it's all or none.
285 */
286static ssize_t sriov_numvfs_store(struct device *dev,
287 struct device_attribute *attr,
288 const char *buf, size_t count)
289{
290 struct pci_dev *pdev = to_pci_dev(dev);
291 int ret;
292 u16 num_vfs;
293
294 ret = kstrtou16(buf, 0, &num_vfs);
295 if (ret < 0)
296 return ret;
297
298 if (num_vfs > pci_sriov_get_totalvfs(pdev))
299 return -ERANGE;
300
301 device_lock(&pdev->dev);
302
303 if (num_vfs == pdev->sriov->num_VFs)
304 goto exit;
305
306 /* is PF driver loaded w/callback */
307 if (!pdev->driver || !pdev->driver->sriov_configure) {
308 pci_info(pdev, "Driver does not support SRIOV configuration via sysfs\n");
309 ret = -ENOENT;
310 goto exit;
311 }
312
313 if (num_vfs == 0) {
314 /* disable VFs */
315 ret = pdev->driver->sriov_configure(pdev, 0);
316 goto exit;
317 }
318
319 /* enable VFs */
320 if (pdev->sriov->num_VFs) {
321 pci_warn(pdev, "%d VFs already enabled. Disable before enabling %d VFs\n",
322 pdev->sriov->num_VFs, num_vfs);
323 ret = -EBUSY;
324 goto exit;
325 }
326
327 ret = pdev->driver->sriov_configure(pdev, num_vfs);
328 if (ret < 0)
329 goto exit;
330
331 if (ret != num_vfs)
332 pci_warn(pdev, "%d VFs requested; only %d enabled\n",
333 num_vfs, ret);
334
335exit:
336 device_unlock(&pdev->dev);
337
338 if (ret < 0)
339 return ret;
340
341 return count;
342}
343
344static ssize_t sriov_offset_show(struct device *dev,
345 struct device_attribute *attr,
346 char *buf)
347{
348 struct pci_dev *pdev = to_pci_dev(dev);
349
350 return sprintf(buf, "%u\n", pdev->sriov->offset);
351}
352
353static ssize_t sriov_stride_show(struct device *dev,
354 struct device_attribute *attr,
355 char *buf)
356{
357 struct pci_dev *pdev = to_pci_dev(dev);
358
359 return sprintf(buf, "%u\n", pdev->sriov->stride);
360}
361
362static ssize_t sriov_vf_device_show(struct device *dev,
363 struct device_attribute *attr,
364 char *buf)
365{
366 struct pci_dev *pdev = to_pci_dev(dev);
367
368 return sprintf(buf, "%x\n", pdev->sriov->vf_device);
369}
370
371static ssize_t sriov_drivers_autoprobe_show(struct device *dev,
372 struct device_attribute *attr,
373 char *buf)
374{
375 struct pci_dev *pdev = to_pci_dev(dev);
376
377 return sprintf(buf, "%u\n", pdev->sriov->drivers_autoprobe);
378}
379
380static ssize_t sriov_drivers_autoprobe_store(struct device *dev,
381 struct device_attribute *attr,
382 const char *buf, size_t count)
383{
384 struct pci_dev *pdev = to_pci_dev(dev);
385 bool drivers_autoprobe;
386
387 if (kstrtobool(buf, &drivers_autoprobe) < 0)
388 return -EINVAL;
389
390 pdev->sriov->drivers_autoprobe = drivers_autoprobe;
391
392 return count;
393}
394
395static DEVICE_ATTR_RO(sriov_totalvfs);
396static DEVICE_ATTR_RW(sriov_numvfs);
397static DEVICE_ATTR_RO(sriov_offset);
398static DEVICE_ATTR_RO(sriov_stride);
399static DEVICE_ATTR_RO(sriov_vf_device);
400static DEVICE_ATTR_RW(sriov_drivers_autoprobe);
401
402static struct attribute *sriov_dev_attrs[] = {
403 &dev_attr_sriov_totalvfs.attr,
404 &dev_attr_sriov_numvfs.attr,
405 &dev_attr_sriov_offset.attr,
406 &dev_attr_sriov_stride.attr,
407 &dev_attr_sriov_vf_device.attr,
408 &dev_attr_sriov_drivers_autoprobe.attr,
409 NULL,
410};
411
412static umode_t sriov_attrs_are_visible(struct kobject *kobj,
413 struct attribute *a, int n)
414{
415 struct device *dev = kobj_to_dev(kobj);
416
417 if (!dev_is_pf(dev))
418 return 0;
419
420 return a->mode;
421}
422
423const struct attribute_group sriov_dev_attr_group = {
424 .attrs = sriov_dev_attrs,
425 .is_visible = sriov_attrs_are_visible,
426};
427
428int __weak pcibios_sriov_enable(struct pci_dev *pdev, u16 num_vfs)
429{
430 return 0;
431}
432
433int __weak pcibios_sriov_disable(struct pci_dev *pdev)
434{
435 return 0;
436}
437
438static int sriov_add_vfs(struct pci_dev *dev, u16 num_vfs)
439{
440 unsigned int i;
441 int rc;
442
443 if (dev->no_vf_scan)
444 return 0;
445
446 for (i = 0; i < num_vfs; i++) {
447 rc = pci_iov_add_virtfn(dev, i);
448 if (rc)
449 goto failed;
450 }
451 return 0;
452failed:
453 while (i--)
454 pci_iov_remove_virtfn(dev, i);
455
456 return rc;
457}
458
459static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
460{
461 int rc;
462 int i;
463 int nres;
464 u16 initial;
465 struct resource *res;
466 struct pci_dev *pdev;
467 struct pci_sriov *iov = dev->sriov;
468 int bars = 0;
469 int bus;
470
471 if (!nr_virtfn)
472 return 0;
473
474 if (iov->num_VFs)
475 return -EINVAL;
476
477 pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial);
478 if (initial > iov->total_VFs ||
479 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total_VFs)))
480 return -EIO;
481
482 if (nr_virtfn < 0 || nr_virtfn > iov->total_VFs ||
483 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
484 return -EINVAL;
485
486 nres = 0;
487 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
488 bars |= (1 << (i + PCI_IOV_RESOURCES));
489 res = &dev->resource[i + PCI_IOV_RESOURCES];
490 if (res->parent)
491 nres++;
492 }
493 if (nres != iov->nres) {
494 pci_err(dev, "not enough MMIO resources for SR-IOV\n");
495 return -ENOMEM;
496 }
497
498 bus = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
499 if (bus > dev->bus->busn_res.end) {
500 pci_err(dev, "can't enable %d VFs (bus %02x out of range of %pR)\n",
501 nr_virtfn, bus, &dev->bus->busn_res);
502 return -ENOMEM;
503 }
504
505 if (pci_enable_resources(dev, bars)) {
506 pci_err(dev, "SR-IOV: IOV BARS not allocated\n");
507 return -ENOMEM;
508 }
509
510 if (iov->link != dev->devfn) {
511 pdev = pci_get_slot(dev->bus, iov->link);
512 if (!pdev)
513 return -ENODEV;
514
515 if (!pdev->is_physfn) {
516 pci_dev_put(pdev);
517 return -ENOSYS;
518 }
519
520 rc = sysfs_create_link(&dev->dev.kobj,
521 &pdev->dev.kobj, "dep_link");
522 pci_dev_put(pdev);
523 if (rc)
524 return rc;
525 }
526
527 iov->initial_VFs = initial;
528 if (nr_virtfn < initial)
529 initial = nr_virtfn;
530
531 rc = pcibios_sriov_enable(dev, initial);
532 if (rc) {
533 pci_err(dev, "failure %d from pcibios_sriov_enable()\n", rc);
534 goto err_pcibios;
535 }
536
537 pci_iov_set_numvfs(dev, nr_virtfn);
538 iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
539 pci_cfg_access_lock(dev);
540 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
541 msleep(100);
542 pci_cfg_access_unlock(dev);
543
544 rc = sriov_add_vfs(dev, initial);
545 if (rc)
546 goto err_pcibios;
547
548 kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE);
549 iov->num_VFs = nr_virtfn;
550
551 return 0;
552
553err_pcibios:
554 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
555 pci_cfg_access_lock(dev);
556 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
557 ssleep(1);
558 pci_cfg_access_unlock(dev);
559
560 pcibios_sriov_disable(dev);
561
562 if (iov->link != dev->devfn)
563 sysfs_remove_link(&dev->dev.kobj, "dep_link");
564
565 pci_iov_set_numvfs(dev, 0);
566 return rc;
567}
568
569static void sriov_del_vfs(struct pci_dev *dev)
570{
571 struct pci_sriov *iov = dev->sriov;
572 int i;
573
574 for (i = 0; i < iov->num_VFs; i++)
575 pci_iov_remove_virtfn(dev, i);
576}
577
578static void sriov_disable(struct pci_dev *dev)
579{
580 struct pci_sriov *iov = dev->sriov;
581
582 if (!iov->num_VFs)
583 return;
584
585 sriov_del_vfs(dev);
586 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
587 pci_cfg_access_lock(dev);
588 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
589 ssleep(1);
590 pci_cfg_access_unlock(dev);
591
592 pcibios_sriov_disable(dev);
593
594 if (iov->link != dev->devfn)
595 sysfs_remove_link(&dev->dev.kobj, "dep_link");
596
597 iov->num_VFs = 0;
598 pci_iov_set_numvfs(dev, 0);
599}
600
601static int sriov_init(struct pci_dev *dev, int pos)
602{
603 int i, bar64;
604 int rc;
605 int nres;
606 u32 pgsz;
607 u16 ctrl, total;
608 struct pci_sriov *iov;
609 struct resource *res;
610 struct pci_dev *pdev;
611
612 pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl);
613 if (ctrl & PCI_SRIOV_CTRL_VFE) {
614 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0);
615 ssleep(1);
616 }
617
618 ctrl = 0;
619 list_for_each_entry(pdev, &dev->bus->devices, bus_list)
620 if (pdev->is_physfn)
621 goto found;
622
623 pdev = NULL;
624 if (pci_ari_enabled(dev->bus))
625 ctrl |= PCI_SRIOV_CTRL_ARI;
626
627found:
628 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl);
629
630 pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total);
631 if (!total)
632 return 0;
633
634 pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz);
635 i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0;
636 pgsz &= ~((1 << i) - 1);
637 if (!pgsz)
638 return -EIO;
639
640 pgsz &= ~(pgsz - 1);
641 pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz);
642
643 iov = kzalloc(sizeof(*iov), GFP_KERNEL);
644 if (!iov)
645 return -ENOMEM;
646
647 nres = 0;
648 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
649 res = &dev->resource[i + PCI_IOV_RESOURCES];
650 /*
651 * If it is already FIXED, don't change it, something
652 * (perhaps EA or header fixups) wants it this way.
653 */
654 if (res->flags & IORESOURCE_PCI_FIXED)
655 bar64 = (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
656 else
657 bar64 = __pci_read_base(dev, pci_bar_unknown, res,
658 pos + PCI_SRIOV_BAR + i * 4);
659 if (!res->flags)
660 continue;
661 if (resource_size(res) & (PAGE_SIZE - 1)) {
662 rc = -EIO;
663 goto failed;
664 }
665 iov->barsz[i] = resource_size(res);
666 res->end = res->start + resource_size(res) * total - 1;
667 pci_info(dev, "VF(n) BAR%d space: %pR (contains BAR%d for %d VFs)\n",
668 i, res, i, total);
669 i += bar64;
670 nres++;
671 }
672
673 iov->pos = pos;
674 iov->nres = nres;
675 iov->ctrl = ctrl;
676 iov->total_VFs = total;
677 iov->driver_max_VFs = total;
678 pci_read_config_word(dev, pos + PCI_SRIOV_VF_DID, &iov->vf_device);
679 iov->pgsz = pgsz;
680 iov->self = dev;
681 iov->drivers_autoprobe = true;
682 pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap);
683 pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link);
684 if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END)
685 iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link);
686
687 if (pdev)
688 iov->dev = pci_dev_get(pdev);
689 else
690 iov->dev = dev;
691
692 dev->sriov = iov;
693 dev->is_physfn = 1;
694 rc = compute_max_vf_buses(dev);
695 if (rc)
696 goto fail_max_buses;
697
698 return 0;
699
700fail_max_buses:
701 dev->sriov = NULL;
702 dev->is_physfn = 0;
703failed:
704 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
705 res = &dev->resource[i + PCI_IOV_RESOURCES];
706 res->flags = 0;
707 }
708
709 kfree(iov);
710 return rc;
711}
712
713static void sriov_release(struct pci_dev *dev)
714{
715 BUG_ON(dev->sriov->num_VFs);
716
717 if (dev != dev->sriov->dev)
718 pci_dev_put(dev->sriov->dev);
719
720 kfree(dev->sriov);
721 dev->sriov = NULL;
722}
723
724static void sriov_restore_state(struct pci_dev *dev)
725{
726 int i;
727 u16 ctrl;
728 struct pci_sriov *iov = dev->sriov;
729
730 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl);
731 if (ctrl & PCI_SRIOV_CTRL_VFE)
732 return;
733
734 /*
735 * Restore PCI_SRIOV_CTRL_ARI before pci_iov_set_numvfs() because
736 * it reads offset & stride, which depend on PCI_SRIOV_CTRL_ARI.
737 */
738 ctrl &= ~PCI_SRIOV_CTRL_ARI;
739 ctrl |= iov->ctrl & PCI_SRIOV_CTRL_ARI;
740 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, ctrl);
741
742 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++)
743 pci_update_resource(dev, i + PCI_IOV_RESOURCES);
744
745 pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
746 pci_iov_set_numvfs(dev, iov->num_VFs);
747 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
748 if (iov->ctrl & PCI_SRIOV_CTRL_VFE)
749 msleep(100);
750}
751
752/**
753 * pci_iov_init - initialize the IOV capability
754 * @dev: the PCI device
755 *
756 * Returns 0 on success, or negative on failure.
757 */
758int pci_iov_init(struct pci_dev *dev)
759{
760 int pos;
761
762 if (!pci_is_pcie(dev))
763 return -ENODEV;
764
765 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV);
766 if (pos)
767 return sriov_init(dev, pos);
768
769 return -ENODEV;
770}
771
772/**
773 * pci_iov_release - release resources used by the IOV capability
774 * @dev: the PCI device
775 */
776void pci_iov_release(struct pci_dev *dev)
777{
778 if (dev->is_physfn)
779 sriov_release(dev);
780}
781
782/**
783 * pci_iov_remove - clean up SR-IOV state after PF driver is detached
784 * @dev: the PCI device
785 */
786void pci_iov_remove(struct pci_dev *dev)
787{
788 struct pci_sriov *iov = dev->sriov;
789
790 if (!dev->is_physfn)
791 return;
792
793 iov->driver_max_VFs = iov->total_VFs;
794 if (iov->num_VFs)
795 pci_warn(dev, "driver left SR-IOV enabled after remove\n");
796}
797
798/**
799 * pci_iov_update_resource - update a VF BAR
800 * @dev: the PCI device
801 * @resno: the resource number
802 *
803 * Update a VF BAR in the SR-IOV capability of a PF.
804 */
805void pci_iov_update_resource(struct pci_dev *dev, int resno)
806{
807 struct pci_sriov *iov = dev->is_physfn ? dev->sriov : NULL;
808 struct resource *res = dev->resource + resno;
809 int vf_bar = resno - PCI_IOV_RESOURCES;
810 struct pci_bus_region region;
811 u16 cmd;
812 u32 new;
813 int reg;
814
815 /*
816 * The generic pci_restore_bars() path calls this for all devices,
817 * including VFs and non-SR-IOV devices. If this is not a PF, we
818 * have nothing to do.
819 */
820 if (!iov)
821 return;
822
823 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &cmd);
824 if ((cmd & PCI_SRIOV_CTRL_VFE) && (cmd & PCI_SRIOV_CTRL_MSE)) {
825 dev_WARN(&dev->dev, "can't update enabled VF BAR%d %pR\n",
826 vf_bar, res);
827 return;
828 }
829
830 /*
831 * Ignore unimplemented BARs, unused resource slots for 64-bit
832 * BARs, and non-movable resources, e.g., those described via
833 * Enhanced Allocation.
834 */
835 if (!res->flags)
836 return;
837
838 if (res->flags & IORESOURCE_UNSET)
839 return;
840
841 if (res->flags & IORESOURCE_PCI_FIXED)
842 return;
843
844 pcibios_resource_to_bus(dev->bus, ®ion, res);
845 new = region.start;
846 new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK;
847
848 reg = iov->pos + PCI_SRIOV_BAR + 4 * vf_bar;
849 pci_write_config_dword(dev, reg, new);
850 if (res->flags & IORESOURCE_MEM_64) {
851 new = region.start >> 16 >> 16;
852 pci_write_config_dword(dev, reg + 4, new);
853 }
854}
855
856resource_size_t __weak pcibios_iov_resource_alignment(struct pci_dev *dev,
857 int resno)
858{
859 return pci_iov_resource_size(dev, resno);
860}
861
862/**
863 * pci_sriov_resource_alignment - get resource alignment for VF BAR
864 * @dev: the PCI device
865 * @resno: the resource number
866 *
867 * Returns the alignment of the VF BAR found in the SR-IOV capability.
868 * This is not the same as the resource size which is defined as
869 * the VF BAR size multiplied by the number of VFs. The alignment
870 * is just the VF BAR size.
871 */
872resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno)
873{
874 return pcibios_iov_resource_alignment(dev, resno);
875}
876
877/**
878 * pci_restore_iov_state - restore the state of the IOV capability
879 * @dev: the PCI device
880 */
881void pci_restore_iov_state(struct pci_dev *dev)
882{
883 if (dev->is_physfn)
884 sriov_restore_state(dev);
885}
886
887/**
888 * pci_vf_drivers_autoprobe - set PF property drivers_autoprobe for VFs
889 * @dev: the PCI device
890 * @auto_probe: set VF drivers auto probe flag
891 */
892void pci_vf_drivers_autoprobe(struct pci_dev *dev, bool auto_probe)
893{
894 if (dev->is_physfn)
895 dev->sriov->drivers_autoprobe = auto_probe;
896}
897
898/**
899 * pci_iov_bus_range - find bus range used by Virtual Function
900 * @bus: the PCI bus
901 *
902 * Returns max number of buses (exclude current one) used by Virtual
903 * Functions.
904 */
905int pci_iov_bus_range(struct pci_bus *bus)
906{
907 int max = 0;
908 struct pci_dev *dev;
909
910 list_for_each_entry(dev, &bus->devices, bus_list) {
911 if (!dev->is_physfn)
912 continue;
913 if (dev->sriov->max_VF_buses > max)
914 max = dev->sriov->max_VF_buses;
915 }
916
917 return max ? max - bus->number : 0;
918}
919
920/**
921 * pci_enable_sriov - enable the SR-IOV capability
922 * @dev: the PCI device
923 * @nr_virtfn: number of virtual functions to enable
924 *
925 * Returns 0 on success, or negative on failure.
926 */
927int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
928{
929 might_sleep();
930
931 if (!dev->is_physfn)
932 return -ENOSYS;
933
934 return sriov_enable(dev, nr_virtfn);
935}
936EXPORT_SYMBOL_GPL(pci_enable_sriov);
937
938/**
939 * pci_disable_sriov - disable the SR-IOV capability
940 * @dev: the PCI device
941 */
942void pci_disable_sriov(struct pci_dev *dev)
943{
944 might_sleep();
945
946 if (!dev->is_physfn)
947 return;
948
949 sriov_disable(dev);
950}
951EXPORT_SYMBOL_GPL(pci_disable_sriov);
952
953/**
954 * pci_num_vf - return number of VFs associated with a PF device_release_driver
955 * @dev: the PCI device
956 *
957 * Returns number of VFs, or 0 if SR-IOV is not enabled.
958 */
959int pci_num_vf(struct pci_dev *dev)
960{
961 if (!dev->is_physfn)
962 return 0;
963
964 return dev->sriov->num_VFs;
965}
966EXPORT_SYMBOL_GPL(pci_num_vf);
967
968/**
969 * pci_vfs_assigned - returns number of VFs are assigned to a guest
970 * @dev: the PCI device
971 *
972 * Returns number of VFs belonging to this device that are assigned to a guest.
973 * If device is not a physical function returns 0.
974 */
975int pci_vfs_assigned(struct pci_dev *dev)
976{
977 struct pci_dev *vfdev;
978 unsigned int vfs_assigned = 0;
979 unsigned short dev_id;
980
981 /* only search if we are a PF */
982 if (!dev->is_physfn)
983 return 0;
984
985 /*
986 * determine the device ID for the VFs, the vendor ID will be the
987 * same as the PF so there is no need to check for that one
988 */
989 dev_id = dev->sriov->vf_device;
990
991 /* loop through all the VFs to see if we own any that are assigned */
992 vfdev = pci_get_device(dev->vendor, dev_id, NULL);
993 while (vfdev) {
994 /*
995 * It is considered assigned if it is a virtual function with
996 * our dev as the physical function and the assigned bit is set
997 */
998 if (vfdev->is_virtfn && (vfdev->physfn == dev) &&
999 pci_is_dev_assigned(vfdev))
1000 vfs_assigned++;
1001
1002 vfdev = pci_get_device(dev->vendor, dev_id, vfdev);
1003 }
1004
1005 return vfs_assigned;
1006}
1007EXPORT_SYMBOL_GPL(pci_vfs_assigned);
1008
1009/**
1010 * pci_sriov_set_totalvfs -- reduce the TotalVFs available
1011 * @dev: the PCI PF device
1012 * @numvfs: number that should be used for TotalVFs supported
1013 *
1014 * Should be called from PF driver's probe routine with
1015 * device's mutex held.
1016 *
1017 * Returns 0 if PF is an SRIOV-capable device and
1018 * value of numvfs valid. If not a PF return -ENOSYS;
1019 * if numvfs is invalid return -EINVAL;
1020 * if VFs already enabled, return -EBUSY.
1021 */
1022int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs)
1023{
1024 if (!dev->is_physfn)
1025 return -ENOSYS;
1026
1027 if (numvfs > dev->sriov->total_VFs)
1028 return -EINVAL;
1029
1030 /* Shouldn't change if VFs already enabled */
1031 if (dev->sriov->ctrl & PCI_SRIOV_CTRL_VFE)
1032 return -EBUSY;
1033
1034 dev->sriov->driver_max_VFs = numvfs;
1035 return 0;
1036}
1037EXPORT_SYMBOL_GPL(pci_sriov_set_totalvfs);
1038
1039/**
1040 * pci_sriov_get_totalvfs -- get total VFs supported on this device
1041 * @dev: the PCI PF device
1042 *
1043 * For a PCIe device with SRIOV support, return the PCIe
1044 * SRIOV capability value of TotalVFs or the value of driver_max_VFs
1045 * if the driver reduced it. Otherwise 0.
1046 */
1047int pci_sriov_get_totalvfs(struct pci_dev *dev)
1048{
1049 if (!dev->is_physfn)
1050 return 0;
1051
1052 return dev->sriov->driver_max_VFs;
1053}
1054EXPORT_SYMBOL_GPL(pci_sriov_get_totalvfs);
1055
1056/**
1057 * pci_sriov_configure_simple - helper to configure SR-IOV
1058 * @dev: the PCI device
1059 * @nr_virtfn: number of virtual functions to enable, 0 to disable
1060 *
1061 * Enable or disable SR-IOV for devices that don't require any PF setup
1062 * before enabling SR-IOV. Return value is negative on error, or number of
1063 * VFs allocated on success.
1064 */
1065int pci_sriov_configure_simple(struct pci_dev *dev, int nr_virtfn)
1066{
1067 int rc;
1068
1069 might_sleep();
1070
1071 if (!dev->is_physfn)
1072 return -ENODEV;
1073
1074 if (pci_vfs_assigned(dev)) {
1075 pci_warn(dev, "Cannot modify SR-IOV while VFs are assigned\n");
1076 return -EPERM;
1077 }
1078
1079 if (nr_virtfn == 0) {
1080 sriov_disable(dev);
1081 return 0;
1082 }
1083
1084 rc = sriov_enable(dev, nr_virtfn);
1085 if (rc < 0)
1086 return rc;
1087
1088 return nr_virtfn;
1089}
1090EXPORT_SYMBOL_GPL(pci_sriov_configure_simple);