Loading...
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 17 /* "virtfn%u\0" for 2^32 - 1 */
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}
34EXPORT_SYMBOL_GPL(pci_iov_virtfn_devfn);
35
36int pci_iov_vf_id(struct pci_dev *dev)
37{
38 struct pci_dev *pf;
39
40 if (!dev->is_virtfn)
41 return -EINVAL;
42
43 pf = pci_physfn(dev);
44 return (pci_dev_id(dev) - (pci_dev_id(pf) + pf->sriov->offset)) /
45 pf->sriov->stride;
46}
47EXPORT_SYMBOL_GPL(pci_iov_vf_id);
48
49/**
50 * pci_iov_get_pf_drvdata - Return the drvdata of a PF
51 * @dev: VF pci_dev
52 * @pf_driver: Device driver required to own the PF
53 *
54 * This must be called from a context that ensures that a VF driver is attached.
55 * The value returned is invalid once the VF driver completes its remove()
56 * callback.
57 *
58 * Locking is achieved by the driver core. A VF driver cannot be probed until
59 * pci_enable_sriov() is called and pci_disable_sriov() does not return until
60 * all VF drivers have completed their remove().
61 *
62 * The PF driver must call pci_disable_sriov() before it begins to destroy the
63 * drvdata.
64 */
65void *pci_iov_get_pf_drvdata(struct pci_dev *dev, struct pci_driver *pf_driver)
66{
67 struct pci_dev *pf_dev;
68
69 if (!dev->is_virtfn)
70 return ERR_PTR(-EINVAL);
71 pf_dev = dev->physfn;
72 if (pf_dev->driver != pf_driver)
73 return ERR_PTR(-EINVAL);
74 return pci_get_drvdata(pf_dev);
75}
76EXPORT_SYMBOL_GPL(pci_iov_get_pf_drvdata);
77
78/*
79 * Per SR-IOV spec sec 3.3.10 and 3.3.11, First VF Offset and VF Stride may
80 * change when NumVFs changes.
81 *
82 * Update iov->offset and iov->stride when NumVFs is written.
83 */
84static inline void pci_iov_set_numvfs(struct pci_dev *dev, int nr_virtfn)
85{
86 struct pci_sriov *iov = dev->sriov;
87
88 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn);
89 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &iov->offset);
90 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &iov->stride);
91}
92
93/*
94 * The PF consumes one bus number. NumVFs, First VF Offset, and VF Stride
95 * determine how many additional bus numbers will be consumed by VFs.
96 *
97 * Iterate over all valid NumVFs, validate offset and stride, and calculate
98 * the maximum number of bus numbers that could ever be required.
99 */
100static int compute_max_vf_buses(struct pci_dev *dev)
101{
102 struct pci_sriov *iov = dev->sriov;
103 int nr_virtfn, busnr, rc = 0;
104
105 for (nr_virtfn = iov->total_VFs; nr_virtfn; nr_virtfn--) {
106 pci_iov_set_numvfs(dev, nr_virtfn);
107 if (!iov->offset || (nr_virtfn > 1 && !iov->stride)) {
108 rc = -EIO;
109 goto out;
110 }
111
112 busnr = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
113 if (busnr > iov->max_VF_buses)
114 iov->max_VF_buses = busnr;
115 }
116
117out:
118 pci_iov_set_numvfs(dev, 0);
119 return rc;
120}
121
122static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr)
123{
124 struct pci_bus *child;
125
126 if (bus->number == busnr)
127 return bus;
128
129 child = pci_find_bus(pci_domain_nr(bus), busnr);
130 if (child)
131 return child;
132
133 child = pci_add_new_bus(bus, NULL, busnr);
134 if (!child)
135 return NULL;
136
137 pci_bus_insert_busn_res(child, busnr, busnr);
138
139 return child;
140}
141
142static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus)
143{
144 if (physbus != virtbus && list_empty(&virtbus->devices))
145 pci_remove_bus(virtbus);
146}
147
148resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)
149{
150 if (!dev->is_physfn)
151 return 0;
152
153 return dev->sriov->barsz[resno - PCI_IOV_RESOURCES];
154}
155
156static void pci_read_vf_config_common(struct pci_dev *virtfn)
157{
158 struct pci_dev *physfn = virtfn->physfn;
159
160 /*
161 * Some config registers are the same across all associated VFs.
162 * Read them once from VF0 so we can skip reading them from the
163 * other VFs.
164 *
165 * PCIe r4.0, sec 9.3.4.1, technically doesn't require all VFs to
166 * have the same Revision ID and Subsystem ID, but we assume they
167 * do.
168 */
169 pci_read_config_dword(virtfn, PCI_CLASS_REVISION,
170 &physfn->sriov->class);
171 pci_read_config_byte(virtfn, PCI_HEADER_TYPE,
172 &physfn->sriov->hdr_type);
173 pci_read_config_word(virtfn, PCI_SUBSYSTEM_VENDOR_ID,
174 &physfn->sriov->subsystem_vendor);
175 pci_read_config_word(virtfn, PCI_SUBSYSTEM_ID,
176 &physfn->sriov->subsystem_device);
177}
178
179int pci_iov_sysfs_link(struct pci_dev *dev,
180 struct pci_dev *virtfn, int id)
181{
182 char buf[VIRTFN_ID_LEN];
183 int rc;
184
185 sprintf(buf, "virtfn%u", id);
186 rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
187 if (rc)
188 goto failed;
189 rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");
190 if (rc)
191 goto failed1;
192
193 kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);
194
195 return 0;
196
197failed1:
198 sysfs_remove_link(&dev->dev.kobj, buf);
199failed:
200 return rc;
201}
202
203#ifdef CONFIG_PCI_MSI
204static ssize_t sriov_vf_total_msix_show(struct device *dev,
205 struct device_attribute *attr,
206 char *buf)
207{
208 struct pci_dev *pdev = to_pci_dev(dev);
209 u32 vf_total_msix = 0;
210
211 device_lock(dev);
212 if (!pdev->driver || !pdev->driver->sriov_get_vf_total_msix)
213 goto unlock;
214
215 vf_total_msix = pdev->driver->sriov_get_vf_total_msix(pdev);
216unlock:
217 device_unlock(dev);
218 return sysfs_emit(buf, "%u\n", vf_total_msix);
219}
220static DEVICE_ATTR_RO(sriov_vf_total_msix);
221
222static ssize_t sriov_vf_msix_count_store(struct device *dev,
223 struct device_attribute *attr,
224 const char *buf, size_t count)
225{
226 struct pci_dev *vf_dev = to_pci_dev(dev);
227 struct pci_dev *pdev = pci_physfn(vf_dev);
228 int val, ret = 0;
229
230 if (kstrtoint(buf, 0, &val) < 0)
231 return -EINVAL;
232
233 if (val < 0)
234 return -EINVAL;
235
236 device_lock(&pdev->dev);
237 if (!pdev->driver || !pdev->driver->sriov_set_msix_vec_count) {
238 ret = -EOPNOTSUPP;
239 goto err_pdev;
240 }
241
242 device_lock(&vf_dev->dev);
243 if (vf_dev->driver) {
244 /*
245 * A driver is already attached to this VF and has configured
246 * itself based on the current MSI-X vector count. Changing
247 * the vector size could mess up the driver, so block it.
248 */
249 ret = -EBUSY;
250 goto err_dev;
251 }
252
253 ret = pdev->driver->sriov_set_msix_vec_count(vf_dev, val);
254
255err_dev:
256 device_unlock(&vf_dev->dev);
257err_pdev:
258 device_unlock(&pdev->dev);
259 return ret ? : count;
260}
261static DEVICE_ATTR_WO(sriov_vf_msix_count);
262#endif
263
264static struct attribute *sriov_vf_dev_attrs[] = {
265#ifdef CONFIG_PCI_MSI
266 &dev_attr_sriov_vf_msix_count.attr,
267#endif
268 NULL,
269};
270
271static umode_t sriov_vf_attrs_are_visible(struct kobject *kobj,
272 struct attribute *a, int n)
273{
274 struct device *dev = kobj_to_dev(kobj);
275 struct pci_dev *pdev = to_pci_dev(dev);
276
277 if (!pdev->is_virtfn)
278 return 0;
279
280 return a->mode;
281}
282
283const struct attribute_group sriov_vf_dev_attr_group = {
284 .attrs = sriov_vf_dev_attrs,
285 .is_visible = sriov_vf_attrs_are_visible,
286};
287
288int pci_iov_add_virtfn(struct pci_dev *dev, int id)
289{
290 int i;
291 int rc = -ENOMEM;
292 u64 size;
293 struct pci_dev *virtfn;
294 struct resource *res;
295 struct pci_sriov *iov = dev->sriov;
296 struct pci_bus *bus;
297
298 bus = virtfn_add_bus(dev->bus, pci_iov_virtfn_bus(dev, id));
299 if (!bus)
300 goto failed;
301
302 virtfn = pci_alloc_dev(bus);
303 if (!virtfn)
304 goto failed0;
305
306 virtfn->devfn = pci_iov_virtfn_devfn(dev, id);
307 virtfn->vendor = dev->vendor;
308 virtfn->device = iov->vf_device;
309 virtfn->is_virtfn = 1;
310 virtfn->physfn = pci_dev_get(dev);
311 virtfn->no_command_memory = 1;
312
313 if (id == 0)
314 pci_read_vf_config_common(virtfn);
315
316 rc = pci_setup_device(virtfn);
317 if (rc)
318 goto failed1;
319
320 virtfn->dev.parent = dev->dev.parent;
321 virtfn->multifunction = 0;
322
323 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
324 res = &dev->resource[i + PCI_IOV_RESOURCES];
325 if (!res->parent)
326 continue;
327 virtfn->resource[i].name = pci_name(virtfn);
328 virtfn->resource[i].flags = res->flags;
329 size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);
330 resource_set_range(&virtfn->resource[i],
331 res->start + size * id, size);
332 rc = request_resource(res, &virtfn->resource[i]);
333 BUG_ON(rc);
334 }
335
336 pci_device_add(virtfn, virtfn->bus);
337 rc = pci_iov_sysfs_link(dev, virtfn, id);
338 if (rc)
339 goto failed1;
340
341 pci_bus_add_device(virtfn);
342
343 return 0;
344
345failed1:
346 pci_stop_and_remove_bus_device(virtfn);
347 pci_dev_put(dev);
348failed0:
349 virtfn_remove_bus(dev->bus, bus);
350failed:
351
352 return rc;
353}
354
355void pci_iov_remove_virtfn(struct pci_dev *dev, int id)
356{
357 char buf[VIRTFN_ID_LEN];
358 struct pci_dev *virtfn;
359
360 virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus),
361 pci_iov_virtfn_bus(dev, id),
362 pci_iov_virtfn_devfn(dev, id));
363 if (!virtfn)
364 return;
365
366 sprintf(buf, "virtfn%u", id);
367 sysfs_remove_link(&dev->dev.kobj, buf);
368 /*
369 * pci_stop_dev() could have been called for this virtfn already,
370 * so the directory for the virtfn may have been removed before.
371 * Double check to avoid spurious sysfs warnings.
372 */
373 if (virtfn->dev.kobj.sd)
374 sysfs_remove_link(&virtfn->dev.kobj, "physfn");
375
376 pci_stop_and_remove_bus_device(virtfn);
377 virtfn_remove_bus(dev->bus, virtfn->bus);
378
379 /* balance pci_get_domain_bus_and_slot() */
380 pci_dev_put(virtfn);
381 pci_dev_put(dev);
382}
383
384static ssize_t sriov_totalvfs_show(struct device *dev,
385 struct device_attribute *attr,
386 char *buf)
387{
388 struct pci_dev *pdev = to_pci_dev(dev);
389
390 return sysfs_emit(buf, "%u\n", pci_sriov_get_totalvfs(pdev));
391}
392
393static ssize_t sriov_numvfs_show(struct device *dev,
394 struct device_attribute *attr,
395 char *buf)
396{
397 struct pci_dev *pdev = to_pci_dev(dev);
398 u16 num_vfs;
399
400 /* Serialize vs sriov_numvfs_store() so readers see valid num_VFs */
401 device_lock(&pdev->dev);
402 num_vfs = pdev->sriov->num_VFs;
403 device_unlock(&pdev->dev);
404
405 return sysfs_emit(buf, "%u\n", num_vfs);
406}
407
408/*
409 * num_vfs > 0; number of VFs to enable
410 * num_vfs = 0; disable all VFs
411 *
412 * Note: SRIOV spec does not allow partial VF
413 * disable, so it's all or none.
414 */
415static ssize_t sriov_numvfs_store(struct device *dev,
416 struct device_attribute *attr,
417 const char *buf, size_t count)
418{
419 struct pci_dev *pdev = to_pci_dev(dev);
420 int ret = 0;
421 u16 num_vfs;
422
423 if (kstrtou16(buf, 0, &num_vfs) < 0)
424 return -EINVAL;
425
426 if (num_vfs > pci_sriov_get_totalvfs(pdev))
427 return -ERANGE;
428
429 device_lock(&pdev->dev);
430
431 if (num_vfs == pdev->sriov->num_VFs)
432 goto exit;
433
434 /* is PF driver loaded */
435 if (!pdev->driver) {
436 pci_info(pdev, "no driver bound to device; cannot configure SR-IOV\n");
437 ret = -ENOENT;
438 goto exit;
439 }
440
441 /* is PF driver loaded w/callback */
442 if (!pdev->driver->sriov_configure) {
443 pci_info(pdev, "driver does not support SR-IOV configuration via sysfs\n");
444 ret = -ENOENT;
445 goto exit;
446 }
447
448 if (num_vfs == 0) {
449 /* disable VFs */
450 ret = pdev->driver->sriov_configure(pdev, 0);
451 goto exit;
452 }
453
454 /* enable VFs */
455 if (pdev->sriov->num_VFs) {
456 pci_warn(pdev, "%d VFs already enabled. Disable before enabling %d VFs\n",
457 pdev->sriov->num_VFs, num_vfs);
458 ret = -EBUSY;
459 goto exit;
460 }
461
462 ret = pdev->driver->sriov_configure(pdev, num_vfs);
463 if (ret < 0)
464 goto exit;
465
466 if (ret != num_vfs)
467 pci_warn(pdev, "%d VFs requested; only %d enabled\n",
468 num_vfs, ret);
469
470exit:
471 device_unlock(&pdev->dev);
472
473 if (ret < 0)
474 return ret;
475
476 return count;
477}
478
479static ssize_t sriov_offset_show(struct device *dev,
480 struct device_attribute *attr,
481 char *buf)
482{
483 struct pci_dev *pdev = to_pci_dev(dev);
484
485 return sysfs_emit(buf, "%u\n", pdev->sriov->offset);
486}
487
488static ssize_t sriov_stride_show(struct device *dev,
489 struct device_attribute *attr,
490 char *buf)
491{
492 struct pci_dev *pdev = to_pci_dev(dev);
493
494 return sysfs_emit(buf, "%u\n", pdev->sriov->stride);
495}
496
497static ssize_t sriov_vf_device_show(struct device *dev,
498 struct device_attribute *attr,
499 char *buf)
500{
501 struct pci_dev *pdev = to_pci_dev(dev);
502
503 return sysfs_emit(buf, "%x\n", pdev->sriov->vf_device);
504}
505
506static ssize_t sriov_drivers_autoprobe_show(struct device *dev,
507 struct device_attribute *attr,
508 char *buf)
509{
510 struct pci_dev *pdev = to_pci_dev(dev);
511
512 return sysfs_emit(buf, "%u\n", pdev->sriov->drivers_autoprobe);
513}
514
515static ssize_t sriov_drivers_autoprobe_store(struct device *dev,
516 struct device_attribute *attr,
517 const char *buf, size_t count)
518{
519 struct pci_dev *pdev = to_pci_dev(dev);
520 bool drivers_autoprobe;
521
522 if (kstrtobool(buf, &drivers_autoprobe) < 0)
523 return -EINVAL;
524
525 pdev->sriov->drivers_autoprobe = drivers_autoprobe;
526
527 return count;
528}
529
530static DEVICE_ATTR_RO(sriov_totalvfs);
531static DEVICE_ATTR_RW(sriov_numvfs);
532static DEVICE_ATTR_RO(sriov_offset);
533static DEVICE_ATTR_RO(sriov_stride);
534static DEVICE_ATTR_RO(sriov_vf_device);
535static DEVICE_ATTR_RW(sriov_drivers_autoprobe);
536
537static struct attribute *sriov_pf_dev_attrs[] = {
538 &dev_attr_sriov_totalvfs.attr,
539 &dev_attr_sriov_numvfs.attr,
540 &dev_attr_sriov_offset.attr,
541 &dev_attr_sriov_stride.attr,
542 &dev_attr_sriov_vf_device.attr,
543 &dev_attr_sriov_drivers_autoprobe.attr,
544#ifdef CONFIG_PCI_MSI
545 &dev_attr_sriov_vf_total_msix.attr,
546#endif
547 NULL,
548};
549
550static umode_t sriov_pf_attrs_are_visible(struct kobject *kobj,
551 struct attribute *a, int n)
552{
553 struct device *dev = kobj_to_dev(kobj);
554
555 if (!dev_is_pf(dev))
556 return 0;
557
558 return a->mode;
559}
560
561const struct attribute_group sriov_pf_dev_attr_group = {
562 .attrs = sriov_pf_dev_attrs,
563 .is_visible = sriov_pf_attrs_are_visible,
564};
565
566int __weak pcibios_sriov_enable(struct pci_dev *pdev, u16 num_vfs)
567{
568 return 0;
569}
570
571int __weak pcibios_sriov_disable(struct pci_dev *pdev)
572{
573 return 0;
574}
575
576static int sriov_add_vfs(struct pci_dev *dev, u16 num_vfs)
577{
578 unsigned int i;
579 int rc;
580
581 if (dev->no_vf_scan)
582 return 0;
583
584 for (i = 0; i < num_vfs; i++) {
585 rc = pci_iov_add_virtfn(dev, i);
586 if (rc)
587 goto failed;
588 }
589 return 0;
590failed:
591 while (i--)
592 pci_iov_remove_virtfn(dev, i);
593
594 return rc;
595}
596
597static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
598{
599 int rc;
600 int i;
601 int nres;
602 u16 initial;
603 struct resource *res;
604 struct pci_dev *pdev;
605 struct pci_sriov *iov = dev->sriov;
606 int bars = 0;
607 int bus;
608
609 if (!nr_virtfn)
610 return 0;
611
612 if (iov->num_VFs)
613 return -EINVAL;
614
615 pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial);
616 if (initial > iov->total_VFs ||
617 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total_VFs)))
618 return -EIO;
619
620 if (nr_virtfn < 0 || nr_virtfn > iov->total_VFs ||
621 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
622 return -EINVAL;
623
624 nres = 0;
625 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
626 bars |= (1 << (i + PCI_IOV_RESOURCES));
627 res = &dev->resource[i + PCI_IOV_RESOURCES];
628 if (res->parent)
629 nres++;
630 }
631 if (nres != iov->nres) {
632 pci_err(dev, "not enough MMIO resources for SR-IOV\n");
633 return -ENOMEM;
634 }
635
636 bus = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
637 if (bus > dev->bus->busn_res.end) {
638 pci_err(dev, "can't enable %d VFs (bus %02x out of range of %pR)\n",
639 nr_virtfn, bus, &dev->bus->busn_res);
640 return -ENOMEM;
641 }
642
643 if (pci_enable_resources(dev, bars)) {
644 pci_err(dev, "SR-IOV: IOV BARS not allocated\n");
645 return -ENOMEM;
646 }
647
648 if (iov->link != dev->devfn) {
649 pdev = pci_get_slot(dev->bus, iov->link);
650 if (!pdev)
651 return -ENODEV;
652
653 if (!pdev->is_physfn) {
654 pci_dev_put(pdev);
655 return -ENOSYS;
656 }
657
658 rc = sysfs_create_link(&dev->dev.kobj,
659 &pdev->dev.kobj, "dep_link");
660 pci_dev_put(pdev);
661 if (rc)
662 return rc;
663 }
664
665 iov->initial_VFs = initial;
666 if (nr_virtfn < initial)
667 initial = nr_virtfn;
668
669 rc = pcibios_sriov_enable(dev, initial);
670 if (rc) {
671 pci_err(dev, "failure %d from pcibios_sriov_enable()\n", rc);
672 goto err_pcibios;
673 }
674
675 pci_iov_set_numvfs(dev, nr_virtfn);
676 iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
677 pci_cfg_access_lock(dev);
678 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
679 msleep(100);
680 pci_cfg_access_unlock(dev);
681
682 rc = sriov_add_vfs(dev, initial);
683 if (rc)
684 goto err_pcibios;
685
686 kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE);
687 iov->num_VFs = nr_virtfn;
688
689 return 0;
690
691err_pcibios:
692 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
693 pci_cfg_access_lock(dev);
694 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
695 ssleep(1);
696 pci_cfg_access_unlock(dev);
697
698 pcibios_sriov_disable(dev);
699
700 if (iov->link != dev->devfn)
701 sysfs_remove_link(&dev->dev.kobj, "dep_link");
702
703 pci_iov_set_numvfs(dev, 0);
704 return rc;
705}
706
707static void sriov_del_vfs(struct pci_dev *dev)
708{
709 struct pci_sriov *iov = dev->sriov;
710 int i;
711
712 for (i = 0; i < iov->num_VFs; i++)
713 pci_iov_remove_virtfn(dev, i);
714}
715
716static void sriov_disable(struct pci_dev *dev)
717{
718 struct pci_sriov *iov = dev->sriov;
719
720 if (!iov->num_VFs)
721 return;
722
723 sriov_del_vfs(dev);
724 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
725 pci_cfg_access_lock(dev);
726 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
727 ssleep(1);
728 pci_cfg_access_unlock(dev);
729
730 pcibios_sriov_disable(dev);
731
732 if (iov->link != dev->devfn)
733 sysfs_remove_link(&dev->dev.kobj, "dep_link");
734
735 iov->num_VFs = 0;
736 pci_iov_set_numvfs(dev, 0);
737}
738
739static int sriov_init(struct pci_dev *dev, int pos)
740{
741 int i, bar64;
742 int rc;
743 int nres;
744 u32 pgsz;
745 u16 ctrl, total;
746 struct pci_sriov *iov;
747 struct resource *res;
748 const char *res_name;
749 struct pci_dev *pdev;
750
751 pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl);
752 if (ctrl & PCI_SRIOV_CTRL_VFE) {
753 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0);
754 ssleep(1);
755 }
756
757 ctrl = 0;
758 list_for_each_entry(pdev, &dev->bus->devices, bus_list)
759 if (pdev->is_physfn)
760 goto found;
761
762 pdev = NULL;
763 if (pci_ari_enabled(dev->bus))
764 ctrl |= PCI_SRIOV_CTRL_ARI;
765
766found:
767 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl);
768
769 pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total);
770 if (!total)
771 return 0;
772
773 pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz);
774 i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0;
775 pgsz &= ~((1 << i) - 1);
776 if (!pgsz)
777 return -EIO;
778
779 pgsz &= ~(pgsz - 1);
780 pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz);
781
782 iov = kzalloc(sizeof(*iov), GFP_KERNEL);
783 if (!iov)
784 return -ENOMEM;
785
786 nres = 0;
787 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
788 res = &dev->resource[i + PCI_IOV_RESOURCES];
789 res_name = pci_resource_name(dev, i + PCI_IOV_RESOURCES);
790
791 /*
792 * If it is already FIXED, don't change it, something
793 * (perhaps EA or header fixups) wants it this way.
794 */
795 if (res->flags & IORESOURCE_PCI_FIXED)
796 bar64 = (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
797 else
798 bar64 = __pci_read_base(dev, pci_bar_unknown, res,
799 pos + PCI_SRIOV_BAR + i * 4);
800 if (!res->flags)
801 continue;
802 if (resource_size(res) & (PAGE_SIZE - 1)) {
803 rc = -EIO;
804 goto failed;
805 }
806 iov->barsz[i] = resource_size(res);
807 resource_set_size(res, resource_size(res) * total);
808 pci_info(dev, "%s %pR: contains BAR %d for %d VFs\n",
809 res_name, res, i, total);
810 i += bar64;
811 nres++;
812 }
813
814 iov->pos = pos;
815 iov->nres = nres;
816 iov->ctrl = ctrl;
817 iov->total_VFs = total;
818 iov->driver_max_VFs = total;
819 pci_read_config_word(dev, pos + PCI_SRIOV_VF_DID, &iov->vf_device);
820 iov->pgsz = pgsz;
821 iov->self = dev;
822 iov->drivers_autoprobe = true;
823 pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap);
824 pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link);
825 if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END)
826 iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link);
827
828 if (pdev)
829 iov->dev = pci_dev_get(pdev);
830 else
831 iov->dev = dev;
832
833 dev->sriov = iov;
834 dev->is_physfn = 1;
835 rc = compute_max_vf_buses(dev);
836 if (rc)
837 goto fail_max_buses;
838
839 return 0;
840
841fail_max_buses:
842 dev->sriov = NULL;
843 dev->is_physfn = 0;
844failed:
845 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
846 res = &dev->resource[i + PCI_IOV_RESOURCES];
847 res->flags = 0;
848 }
849
850 kfree(iov);
851 return rc;
852}
853
854static void sriov_release(struct pci_dev *dev)
855{
856 BUG_ON(dev->sriov->num_VFs);
857
858 if (dev != dev->sriov->dev)
859 pci_dev_put(dev->sriov->dev);
860
861 kfree(dev->sriov);
862 dev->sriov = NULL;
863}
864
865static void sriov_restore_state(struct pci_dev *dev)
866{
867 int i;
868 u16 ctrl;
869 struct pci_sriov *iov = dev->sriov;
870
871 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl);
872 if (ctrl & PCI_SRIOV_CTRL_VFE)
873 return;
874
875 /*
876 * Restore PCI_SRIOV_CTRL_ARI before pci_iov_set_numvfs() because
877 * it reads offset & stride, which depend on PCI_SRIOV_CTRL_ARI.
878 */
879 ctrl &= ~PCI_SRIOV_CTRL_ARI;
880 ctrl |= iov->ctrl & PCI_SRIOV_CTRL_ARI;
881 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, ctrl);
882
883 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++)
884 pci_update_resource(dev, i + PCI_IOV_RESOURCES);
885
886 pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
887 pci_iov_set_numvfs(dev, iov->num_VFs);
888 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
889 if (iov->ctrl & PCI_SRIOV_CTRL_VFE)
890 msleep(100);
891}
892
893/**
894 * pci_iov_init - initialize the IOV capability
895 * @dev: the PCI device
896 *
897 * Returns 0 on success, or negative on failure.
898 */
899int pci_iov_init(struct pci_dev *dev)
900{
901 int pos;
902
903 if (!pci_is_pcie(dev))
904 return -ENODEV;
905
906 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV);
907 if (pos)
908 return sriov_init(dev, pos);
909
910 return -ENODEV;
911}
912
913/**
914 * pci_iov_release - release resources used by the IOV capability
915 * @dev: the PCI device
916 */
917void pci_iov_release(struct pci_dev *dev)
918{
919 if (dev->is_physfn)
920 sriov_release(dev);
921}
922
923/**
924 * pci_iov_remove - clean up SR-IOV state after PF driver is detached
925 * @dev: the PCI device
926 */
927void pci_iov_remove(struct pci_dev *dev)
928{
929 struct pci_sriov *iov = dev->sriov;
930
931 if (!dev->is_physfn)
932 return;
933
934 iov->driver_max_VFs = iov->total_VFs;
935 if (iov->num_VFs)
936 pci_warn(dev, "driver left SR-IOV enabled after remove\n");
937}
938
939/**
940 * pci_iov_update_resource - update a VF BAR
941 * @dev: the PCI device
942 * @resno: the resource number
943 *
944 * Update a VF BAR in the SR-IOV capability of a PF.
945 */
946void pci_iov_update_resource(struct pci_dev *dev, int resno)
947{
948 struct pci_sriov *iov = dev->is_physfn ? dev->sriov : NULL;
949 struct resource *res = dev->resource + resno;
950 int vf_bar = resno - PCI_IOV_RESOURCES;
951 struct pci_bus_region region;
952 u16 cmd;
953 u32 new;
954 int reg;
955
956 /*
957 * The generic pci_restore_bars() path calls this for all devices,
958 * including VFs and non-SR-IOV devices. If this is not a PF, we
959 * have nothing to do.
960 */
961 if (!iov)
962 return;
963
964 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &cmd);
965 if ((cmd & PCI_SRIOV_CTRL_VFE) && (cmd & PCI_SRIOV_CTRL_MSE)) {
966 dev_WARN(&dev->dev, "can't update enabled VF BAR%d %pR\n",
967 vf_bar, res);
968 return;
969 }
970
971 /*
972 * Ignore unimplemented BARs, unused resource slots for 64-bit
973 * BARs, and non-movable resources, e.g., those described via
974 * Enhanced Allocation.
975 */
976 if (!res->flags)
977 return;
978
979 if (res->flags & IORESOURCE_UNSET)
980 return;
981
982 if (res->flags & IORESOURCE_PCI_FIXED)
983 return;
984
985 pcibios_resource_to_bus(dev->bus, ®ion, res);
986 new = region.start;
987 new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK;
988
989 reg = iov->pos + PCI_SRIOV_BAR + 4 * vf_bar;
990 pci_write_config_dword(dev, reg, new);
991 if (res->flags & IORESOURCE_MEM_64) {
992 new = region.start >> 16 >> 16;
993 pci_write_config_dword(dev, reg + 4, new);
994 }
995}
996
997resource_size_t __weak pcibios_iov_resource_alignment(struct pci_dev *dev,
998 int resno)
999{
1000 return pci_iov_resource_size(dev, resno);
1001}
1002
1003/**
1004 * pci_sriov_resource_alignment - get resource alignment for VF BAR
1005 * @dev: the PCI device
1006 * @resno: the resource number
1007 *
1008 * Returns the alignment of the VF BAR found in the SR-IOV capability.
1009 * This is not the same as the resource size which is defined as
1010 * the VF BAR size multiplied by the number of VFs. The alignment
1011 * is just the VF BAR size.
1012 */
1013resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno)
1014{
1015 return pcibios_iov_resource_alignment(dev, resno);
1016}
1017
1018/**
1019 * pci_restore_iov_state - restore the state of the IOV capability
1020 * @dev: the PCI device
1021 */
1022void pci_restore_iov_state(struct pci_dev *dev)
1023{
1024 if (dev->is_physfn)
1025 sriov_restore_state(dev);
1026}
1027
1028/**
1029 * pci_vf_drivers_autoprobe - set PF property drivers_autoprobe for VFs
1030 * @dev: the PCI device
1031 * @auto_probe: set VF drivers auto probe flag
1032 */
1033void pci_vf_drivers_autoprobe(struct pci_dev *dev, bool auto_probe)
1034{
1035 if (dev->is_physfn)
1036 dev->sriov->drivers_autoprobe = auto_probe;
1037}
1038
1039/**
1040 * pci_iov_bus_range - find bus range used by Virtual Function
1041 * @bus: the PCI bus
1042 *
1043 * Returns max number of buses (exclude current one) used by Virtual
1044 * Functions.
1045 */
1046int pci_iov_bus_range(struct pci_bus *bus)
1047{
1048 int max = 0;
1049 struct pci_dev *dev;
1050
1051 list_for_each_entry(dev, &bus->devices, bus_list) {
1052 if (!dev->is_physfn)
1053 continue;
1054 if (dev->sriov->max_VF_buses > max)
1055 max = dev->sriov->max_VF_buses;
1056 }
1057
1058 return max ? max - bus->number : 0;
1059}
1060
1061/**
1062 * pci_enable_sriov - enable the SR-IOV capability
1063 * @dev: the PCI device
1064 * @nr_virtfn: number of virtual functions to enable
1065 *
1066 * Returns 0 on success, or negative on failure.
1067 */
1068int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
1069{
1070 might_sleep();
1071
1072 if (!dev->is_physfn)
1073 return -ENOSYS;
1074
1075 return sriov_enable(dev, nr_virtfn);
1076}
1077EXPORT_SYMBOL_GPL(pci_enable_sriov);
1078
1079/**
1080 * pci_disable_sriov - disable the SR-IOV capability
1081 * @dev: the PCI device
1082 */
1083void pci_disable_sriov(struct pci_dev *dev)
1084{
1085 might_sleep();
1086
1087 if (!dev->is_physfn)
1088 return;
1089
1090 sriov_disable(dev);
1091}
1092EXPORT_SYMBOL_GPL(pci_disable_sriov);
1093
1094/**
1095 * pci_num_vf - return number of VFs associated with a PF device_release_driver
1096 * @dev: the PCI device
1097 *
1098 * Returns number of VFs, or 0 if SR-IOV is not enabled.
1099 */
1100int pci_num_vf(struct pci_dev *dev)
1101{
1102 if (!dev->is_physfn)
1103 return 0;
1104
1105 return dev->sriov->num_VFs;
1106}
1107EXPORT_SYMBOL_GPL(pci_num_vf);
1108
1109/**
1110 * pci_vfs_assigned - returns number of VFs are assigned to a guest
1111 * @dev: the PCI device
1112 *
1113 * Returns number of VFs belonging to this device that are assigned to a guest.
1114 * If device is not a physical function returns 0.
1115 */
1116int pci_vfs_assigned(struct pci_dev *dev)
1117{
1118 struct pci_dev *vfdev;
1119 unsigned int vfs_assigned = 0;
1120 unsigned short dev_id;
1121
1122 /* only search if we are a PF */
1123 if (!dev->is_physfn)
1124 return 0;
1125
1126 /*
1127 * determine the device ID for the VFs, the vendor ID will be the
1128 * same as the PF so there is no need to check for that one
1129 */
1130 dev_id = dev->sriov->vf_device;
1131
1132 /* loop through all the VFs to see if we own any that are assigned */
1133 vfdev = pci_get_device(dev->vendor, dev_id, NULL);
1134 while (vfdev) {
1135 /*
1136 * It is considered assigned if it is a virtual function with
1137 * our dev as the physical function and the assigned bit is set
1138 */
1139 if (vfdev->is_virtfn && (vfdev->physfn == dev) &&
1140 pci_is_dev_assigned(vfdev))
1141 vfs_assigned++;
1142
1143 vfdev = pci_get_device(dev->vendor, dev_id, vfdev);
1144 }
1145
1146 return vfs_assigned;
1147}
1148EXPORT_SYMBOL_GPL(pci_vfs_assigned);
1149
1150/**
1151 * pci_sriov_set_totalvfs -- reduce the TotalVFs available
1152 * @dev: the PCI PF device
1153 * @numvfs: number that should be used for TotalVFs supported
1154 *
1155 * Should be called from PF driver's probe routine with
1156 * device's mutex held.
1157 *
1158 * Returns 0 if PF is an SRIOV-capable device and
1159 * value of numvfs valid. If not a PF return -ENOSYS;
1160 * if numvfs is invalid return -EINVAL;
1161 * if VFs already enabled, return -EBUSY.
1162 */
1163int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs)
1164{
1165 if (!dev->is_physfn)
1166 return -ENOSYS;
1167
1168 if (numvfs > dev->sriov->total_VFs)
1169 return -EINVAL;
1170
1171 /* Shouldn't change if VFs already enabled */
1172 if (dev->sriov->ctrl & PCI_SRIOV_CTRL_VFE)
1173 return -EBUSY;
1174
1175 dev->sriov->driver_max_VFs = numvfs;
1176 return 0;
1177}
1178EXPORT_SYMBOL_GPL(pci_sriov_set_totalvfs);
1179
1180/**
1181 * pci_sriov_get_totalvfs -- get total VFs supported on this device
1182 * @dev: the PCI PF device
1183 *
1184 * For a PCIe device with SRIOV support, return the PCIe
1185 * SRIOV capability value of TotalVFs or the value of driver_max_VFs
1186 * if the driver reduced it. Otherwise 0.
1187 */
1188int pci_sriov_get_totalvfs(struct pci_dev *dev)
1189{
1190 if (!dev->is_physfn)
1191 return 0;
1192
1193 return dev->sriov->driver_max_VFs;
1194}
1195EXPORT_SYMBOL_GPL(pci_sriov_get_totalvfs);
1196
1197/**
1198 * pci_sriov_configure_simple - helper to configure SR-IOV
1199 * @dev: the PCI device
1200 * @nr_virtfn: number of virtual functions to enable, 0 to disable
1201 *
1202 * Enable or disable SR-IOV for devices that don't require any PF setup
1203 * before enabling SR-IOV. Return value is negative on error, or number of
1204 * VFs allocated on success.
1205 */
1206int pci_sriov_configure_simple(struct pci_dev *dev, int nr_virtfn)
1207{
1208 int rc;
1209
1210 might_sleep();
1211
1212 if (!dev->is_physfn)
1213 return -ENODEV;
1214
1215 if (pci_vfs_assigned(dev)) {
1216 pci_warn(dev, "Cannot modify SR-IOV while VFs are assigned\n");
1217 return -EPERM;
1218 }
1219
1220 if (nr_virtfn == 0) {
1221 sriov_disable(dev);
1222 return 0;
1223 }
1224
1225 rc = sriov_enable(dev, nr_virtfn);
1226 if (rc < 0)
1227 return rc;
1228
1229 return nr_virtfn;
1230}
1231EXPORT_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);