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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/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}
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 (((dev->bus->number << 8) + dev->devfn) -
45 ((pf->bus->number << 8) + pf->devfn + pf->sriov->offset)) /
46 pf->sriov->stride;
47}
48EXPORT_SYMBOL_GPL(pci_iov_vf_id);
49
50/**
51 * pci_iov_get_pf_drvdata - Return the drvdata of a PF
52 * @dev: VF pci_dev
53 * @pf_driver: Device driver required to own the PF
54 *
55 * This must be called from a context that ensures that a VF driver is attached.
56 * The value returned is invalid once the VF driver completes its remove()
57 * callback.
58 *
59 * Locking is achieved by the driver core. A VF driver cannot be probed until
60 * pci_enable_sriov() is called and pci_disable_sriov() does not return until
61 * all VF drivers have completed their remove().
62 *
63 * The PF driver must call pci_disable_sriov() before it begins to destroy the
64 * drvdata.
65 */
66void *pci_iov_get_pf_drvdata(struct pci_dev *dev, struct pci_driver *pf_driver)
67{
68 struct pci_dev *pf_dev;
69
70 if (!dev->is_virtfn)
71 return ERR_PTR(-EINVAL);
72 pf_dev = dev->physfn;
73 if (pf_dev->driver != pf_driver)
74 return ERR_PTR(-EINVAL);
75 return pci_get_drvdata(pf_dev);
76}
77EXPORT_SYMBOL_GPL(pci_iov_get_pf_drvdata);
78
79/*
80 * Per SR-IOV spec sec 3.3.10 and 3.3.11, First VF Offset and VF Stride may
81 * change when NumVFs changes.
82 *
83 * Update iov->offset and iov->stride when NumVFs is written.
84 */
85static inline void pci_iov_set_numvfs(struct pci_dev *dev, int nr_virtfn)
86{
87 struct pci_sriov *iov = dev->sriov;
88
89 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn);
90 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &iov->offset);
91 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &iov->stride);
92}
93
94/*
95 * The PF consumes one bus number. NumVFs, First VF Offset, and VF Stride
96 * determine how many additional bus numbers will be consumed by VFs.
97 *
98 * Iterate over all valid NumVFs, validate offset and stride, and calculate
99 * the maximum number of bus numbers that could ever be required.
100 */
101static int compute_max_vf_buses(struct pci_dev *dev)
102{
103 struct pci_sriov *iov = dev->sriov;
104 int nr_virtfn, busnr, rc = 0;
105
106 for (nr_virtfn = iov->total_VFs; nr_virtfn; nr_virtfn--) {
107 pci_iov_set_numvfs(dev, nr_virtfn);
108 if (!iov->offset || (nr_virtfn > 1 && !iov->stride)) {
109 rc = -EIO;
110 goto out;
111 }
112
113 busnr = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
114 if (busnr > iov->max_VF_buses)
115 iov->max_VF_buses = busnr;
116 }
117
118out:
119 pci_iov_set_numvfs(dev, 0);
120 return rc;
121}
122
123static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr)
124{
125 struct pci_bus *child;
126
127 if (bus->number == busnr)
128 return bus;
129
130 child = pci_find_bus(pci_domain_nr(bus), busnr);
131 if (child)
132 return child;
133
134 child = pci_add_new_bus(bus, NULL, busnr);
135 if (!child)
136 return NULL;
137
138 pci_bus_insert_busn_res(child, busnr, busnr);
139
140 return child;
141}
142
143static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus)
144{
145 if (physbus != virtbus && list_empty(&virtbus->devices))
146 pci_remove_bus(virtbus);
147}
148
149resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)
150{
151 if (!dev->is_physfn)
152 return 0;
153
154 return dev->sriov->barsz[resno - PCI_IOV_RESOURCES];
155}
156
157static void pci_read_vf_config_common(struct pci_dev *virtfn)
158{
159 struct pci_dev *physfn = virtfn->physfn;
160
161 /*
162 * Some config registers are the same across all associated VFs.
163 * Read them once from VF0 so we can skip reading them from the
164 * other VFs.
165 *
166 * PCIe r4.0, sec 9.3.4.1, technically doesn't require all VFs to
167 * have the same Revision ID and Subsystem ID, but we assume they
168 * do.
169 */
170 pci_read_config_dword(virtfn, PCI_CLASS_REVISION,
171 &physfn->sriov->class);
172 pci_read_config_byte(virtfn, PCI_HEADER_TYPE,
173 &physfn->sriov->hdr_type);
174 pci_read_config_word(virtfn, PCI_SUBSYSTEM_VENDOR_ID,
175 &physfn->sriov->subsystem_vendor);
176 pci_read_config_word(virtfn, PCI_SUBSYSTEM_ID,
177 &physfn->sriov->subsystem_device);
178}
179
180int pci_iov_sysfs_link(struct pci_dev *dev,
181 struct pci_dev *virtfn, int id)
182{
183 char buf[VIRTFN_ID_LEN];
184 int rc;
185
186 sprintf(buf, "virtfn%u", id);
187 rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
188 if (rc)
189 goto failed;
190 rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");
191 if (rc)
192 goto failed1;
193
194 kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);
195
196 return 0;
197
198failed1:
199 sysfs_remove_link(&dev->dev.kobj, buf);
200failed:
201 return rc;
202}
203
204#ifdef CONFIG_PCI_MSI
205static ssize_t sriov_vf_total_msix_show(struct device *dev,
206 struct device_attribute *attr,
207 char *buf)
208{
209 struct pci_dev *pdev = to_pci_dev(dev);
210 u32 vf_total_msix = 0;
211
212 device_lock(dev);
213 if (!pdev->driver || !pdev->driver->sriov_get_vf_total_msix)
214 goto unlock;
215
216 vf_total_msix = pdev->driver->sriov_get_vf_total_msix(pdev);
217unlock:
218 device_unlock(dev);
219 return sysfs_emit(buf, "%u\n", vf_total_msix);
220}
221static DEVICE_ATTR_RO(sriov_vf_total_msix);
222
223static ssize_t sriov_vf_msix_count_store(struct device *dev,
224 struct device_attribute *attr,
225 const char *buf, size_t count)
226{
227 struct pci_dev *vf_dev = to_pci_dev(dev);
228 struct pci_dev *pdev = pci_physfn(vf_dev);
229 int val, ret = 0;
230
231 if (kstrtoint(buf, 0, &val) < 0)
232 return -EINVAL;
233
234 if (val < 0)
235 return -EINVAL;
236
237 device_lock(&pdev->dev);
238 if (!pdev->driver || !pdev->driver->sriov_set_msix_vec_count) {
239 ret = -EOPNOTSUPP;
240 goto err_pdev;
241 }
242
243 device_lock(&vf_dev->dev);
244 if (vf_dev->driver) {
245 /*
246 * A driver is already attached to this VF and has configured
247 * itself based on the current MSI-X vector count. Changing
248 * the vector size could mess up the driver, so block it.
249 */
250 ret = -EBUSY;
251 goto err_dev;
252 }
253
254 ret = pdev->driver->sriov_set_msix_vec_count(vf_dev, val);
255
256err_dev:
257 device_unlock(&vf_dev->dev);
258err_pdev:
259 device_unlock(&pdev->dev);
260 return ret ? : count;
261}
262static DEVICE_ATTR_WO(sriov_vf_msix_count);
263#endif
264
265static struct attribute *sriov_vf_dev_attrs[] = {
266#ifdef CONFIG_PCI_MSI
267 &dev_attr_sriov_vf_msix_count.attr,
268#endif
269 NULL,
270};
271
272static umode_t sriov_vf_attrs_are_visible(struct kobject *kobj,
273 struct attribute *a, int n)
274{
275 struct device *dev = kobj_to_dev(kobj);
276 struct pci_dev *pdev = to_pci_dev(dev);
277
278 if (!pdev->is_virtfn)
279 return 0;
280
281 return a->mode;
282}
283
284const struct attribute_group sriov_vf_dev_attr_group = {
285 .attrs = sriov_vf_dev_attrs,
286 .is_visible = sriov_vf_attrs_are_visible,
287};
288
289int pci_iov_add_virtfn(struct pci_dev *dev, int id)
290{
291 int i;
292 int rc = -ENOMEM;
293 u64 size;
294 struct pci_dev *virtfn;
295 struct resource *res;
296 struct pci_sriov *iov = dev->sriov;
297 struct pci_bus *bus;
298
299 bus = virtfn_add_bus(dev->bus, pci_iov_virtfn_bus(dev, id));
300 if (!bus)
301 goto failed;
302
303 virtfn = pci_alloc_dev(bus);
304 if (!virtfn)
305 goto failed0;
306
307 virtfn->devfn = pci_iov_virtfn_devfn(dev, id);
308 virtfn->vendor = dev->vendor;
309 virtfn->device = iov->vf_device;
310 virtfn->is_virtfn = 1;
311 virtfn->physfn = pci_dev_get(dev);
312 virtfn->no_command_memory = 1;
313
314 if (id == 0)
315 pci_read_vf_config_common(virtfn);
316
317 rc = pci_setup_device(virtfn);
318 if (rc)
319 goto failed1;
320
321 virtfn->dev.parent = dev->dev.parent;
322 virtfn->multifunction = 0;
323
324 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
325 res = &dev->resource[i + PCI_IOV_RESOURCES];
326 if (!res->parent)
327 continue;
328 virtfn->resource[i].name = pci_name(virtfn);
329 virtfn->resource[i].flags = res->flags;
330 size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);
331 virtfn->resource[i].start = res->start + size * id;
332 virtfn->resource[i].end = virtfn->resource[i].start + size - 1;
333 rc = request_resource(res, &virtfn->resource[i]);
334 BUG_ON(rc);
335 }
336
337 pci_device_add(virtfn, virtfn->bus);
338 rc = pci_iov_sysfs_link(dev, virtfn, id);
339 if (rc)
340 goto failed1;
341
342 pci_bus_add_device(virtfn);
343
344 return 0;
345
346failed1:
347 pci_stop_and_remove_bus_device(virtfn);
348 pci_dev_put(dev);
349failed0:
350 virtfn_remove_bus(dev->bus, bus);
351failed:
352
353 return rc;
354}
355
356void pci_iov_remove_virtfn(struct pci_dev *dev, int id)
357{
358 char buf[VIRTFN_ID_LEN];
359 struct pci_dev *virtfn;
360
361 virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus),
362 pci_iov_virtfn_bus(dev, id),
363 pci_iov_virtfn_devfn(dev, id));
364 if (!virtfn)
365 return;
366
367 sprintf(buf, "virtfn%u", id);
368 sysfs_remove_link(&dev->dev.kobj, buf);
369 /*
370 * pci_stop_dev() could have been called for this virtfn already,
371 * so the directory for the virtfn may have been removed before.
372 * Double check to avoid spurious sysfs warnings.
373 */
374 if (virtfn->dev.kobj.sd)
375 sysfs_remove_link(&virtfn->dev.kobj, "physfn");
376
377 pci_stop_and_remove_bus_device(virtfn);
378 virtfn_remove_bus(dev->bus, virtfn->bus);
379
380 /* balance pci_get_domain_bus_and_slot() */
381 pci_dev_put(virtfn);
382 pci_dev_put(dev);
383}
384
385static ssize_t sriov_totalvfs_show(struct device *dev,
386 struct device_attribute *attr,
387 char *buf)
388{
389 struct pci_dev *pdev = to_pci_dev(dev);
390
391 return sysfs_emit(buf, "%u\n", pci_sriov_get_totalvfs(pdev));
392}
393
394static ssize_t sriov_numvfs_show(struct device *dev,
395 struct device_attribute *attr,
396 char *buf)
397{
398 struct pci_dev *pdev = to_pci_dev(dev);
399 u16 num_vfs;
400
401 /* Serialize vs sriov_numvfs_store() so readers see valid num_VFs */
402 device_lock(&pdev->dev);
403 num_vfs = pdev->sriov->num_VFs;
404 device_unlock(&pdev->dev);
405
406 return sysfs_emit(buf, "%u\n", num_vfs);
407}
408
409/*
410 * num_vfs > 0; number of VFs to enable
411 * num_vfs = 0; disable all VFs
412 *
413 * Note: SRIOV spec does not allow partial VF
414 * disable, so it's all or none.
415 */
416static ssize_t sriov_numvfs_store(struct device *dev,
417 struct device_attribute *attr,
418 const char *buf, size_t count)
419{
420 struct pci_dev *pdev = to_pci_dev(dev);
421 int ret = 0;
422 u16 num_vfs;
423
424 if (kstrtou16(buf, 0, &num_vfs) < 0)
425 return -EINVAL;
426
427 if (num_vfs > pci_sriov_get_totalvfs(pdev))
428 return -ERANGE;
429
430 device_lock(&pdev->dev);
431
432 if (num_vfs == pdev->sriov->num_VFs)
433 goto exit;
434
435 /* is PF driver loaded */
436 if (!pdev->driver) {
437 pci_info(pdev, "no driver bound to device; cannot configure SR-IOV\n");
438 ret = -ENOENT;
439 goto exit;
440 }
441
442 /* is PF driver loaded w/callback */
443 if (!pdev->driver->sriov_configure) {
444 pci_info(pdev, "driver does not support SR-IOV configuration via sysfs\n");
445 ret = -ENOENT;
446 goto exit;
447 }
448
449 if (num_vfs == 0) {
450 /* disable VFs */
451 ret = pdev->driver->sriov_configure(pdev, 0);
452 goto exit;
453 }
454
455 /* enable VFs */
456 if (pdev->sriov->num_VFs) {
457 pci_warn(pdev, "%d VFs already enabled. Disable before enabling %d VFs\n",
458 pdev->sriov->num_VFs, num_vfs);
459 ret = -EBUSY;
460 goto exit;
461 }
462
463 ret = pdev->driver->sriov_configure(pdev, num_vfs);
464 if (ret < 0)
465 goto exit;
466
467 if (ret != num_vfs)
468 pci_warn(pdev, "%d VFs requested; only %d enabled\n",
469 num_vfs, ret);
470
471exit:
472 device_unlock(&pdev->dev);
473
474 if (ret < 0)
475 return ret;
476
477 return count;
478}
479
480static ssize_t sriov_offset_show(struct device *dev,
481 struct device_attribute *attr,
482 char *buf)
483{
484 struct pci_dev *pdev = to_pci_dev(dev);
485
486 return sysfs_emit(buf, "%u\n", pdev->sriov->offset);
487}
488
489static ssize_t sriov_stride_show(struct device *dev,
490 struct device_attribute *attr,
491 char *buf)
492{
493 struct pci_dev *pdev = to_pci_dev(dev);
494
495 return sysfs_emit(buf, "%u\n", pdev->sriov->stride);
496}
497
498static ssize_t sriov_vf_device_show(struct device *dev,
499 struct device_attribute *attr,
500 char *buf)
501{
502 struct pci_dev *pdev = to_pci_dev(dev);
503
504 return sysfs_emit(buf, "%x\n", pdev->sriov->vf_device);
505}
506
507static ssize_t sriov_drivers_autoprobe_show(struct device *dev,
508 struct device_attribute *attr,
509 char *buf)
510{
511 struct pci_dev *pdev = to_pci_dev(dev);
512
513 return sysfs_emit(buf, "%u\n", pdev->sriov->drivers_autoprobe);
514}
515
516static ssize_t sriov_drivers_autoprobe_store(struct device *dev,
517 struct device_attribute *attr,
518 const char *buf, size_t count)
519{
520 struct pci_dev *pdev = to_pci_dev(dev);
521 bool drivers_autoprobe;
522
523 if (kstrtobool(buf, &drivers_autoprobe) < 0)
524 return -EINVAL;
525
526 pdev->sriov->drivers_autoprobe = drivers_autoprobe;
527
528 return count;
529}
530
531static DEVICE_ATTR_RO(sriov_totalvfs);
532static DEVICE_ATTR_RW(sriov_numvfs);
533static DEVICE_ATTR_RO(sriov_offset);
534static DEVICE_ATTR_RO(sriov_stride);
535static DEVICE_ATTR_RO(sriov_vf_device);
536static DEVICE_ATTR_RW(sriov_drivers_autoprobe);
537
538static struct attribute *sriov_pf_dev_attrs[] = {
539 &dev_attr_sriov_totalvfs.attr,
540 &dev_attr_sriov_numvfs.attr,
541 &dev_attr_sriov_offset.attr,
542 &dev_attr_sriov_stride.attr,
543 &dev_attr_sriov_vf_device.attr,
544 &dev_attr_sriov_drivers_autoprobe.attr,
545#ifdef CONFIG_PCI_MSI
546 &dev_attr_sriov_vf_total_msix.attr,
547#endif
548 NULL,
549};
550
551static umode_t sriov_pf_attrs_are_visible(struct kobject *kobj,
552 struct attribute *a, int n)
553{
554 struct device *dev = kobj_to_dev(kobj);
555
556 if (!dev_is_pf(dev))
557 return 0;
558
559 return a->mode;
560}
561
562const struct attribute_group sriov_pf_dev_attr_group = {
563 .attrs = sriov_pf_dev_attrs,
564 .is_visible = sriov_pf_attrs_are_visible,
565};
566
567int __weak pcibios_sriov_enable(struct pci_dev *pdev, u16 num_vfs)
568{
569 return 0;
570}
571
572int __weak pcibios_sriov_disable(struct pci_dev *pdev)
573{
574 return 0;
575}
576
577static int sriov_add_vfs(struct pci_dev *dev, u16 num_vfs)
578{
579 unsigned int i;
580 int rc;
581
582 if (dev->no_vf_scan)
583 return 0;
584
585 for (i = 0; i < num_vfs; i++) {
586 rc = pci_iov_add_virtfn(dev, i);
587 if (rc)
588 goto failed;
589 }
590 return 0;
591failed:
592 while (i--)
593 pci_iov_remove_virtfn(dev, i);
594
595 return rc;
596}
597
598static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
599{
600 int rc;
601 int i;
602 int nres;
603 u16 initial;
604 struct resource *res;
605 struct pci_dev *pdev;
606 struct pci_sriov *iov = dev->sriov;
607 int bars = 0;
608 int bus;
609
610 if (!nr_virtfn)
611 return 0;
612
613 if (iov->num_VFs)
614 return -EINVAL;
615
616 pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial);
617 if (initial > iov->total_VFs ||
618 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total_VFs)))
619 return -EIO;
620
621 if (nr_virtfn < 0 || nr_virtfn > iov->total_VFs ||
622 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
623 return -EINVAL;
624
625 nres = 0;
626 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
627 bars |= (1 << (i + PCI_IOV_RESOURCES));
628 res = &dev->resource[i + PCI_IOV_RESOURCES];
629 if (res->parent)
630 nres++;
631 }
632 if (nres != iov->nres) {
633 pci_err(dev, "not enough MMIO resources for SR-IOV\n");
634 return -ENOMEM;
635 }
636
637 bus = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
638 if (bus > dev->bus->busn_res.end) {
639 pci_err(dev, "can't enable %d VFs (bus %02x out of range of %pR)\n",
640 nr_virtfn, bus, &dev->bus->busn_res);
641 return -ENOMEM;
642 }
643
644 if (pci_enable_resources(dev, bars)) {
645 pci_err(dev, "SR-IOV: IOV BARS not allocated\n");
646 return -ENOMEM;
647 }
648
649 if (iov->link != dev->devfn) {
650 pdev = pci_get_slot(dev->bus, iov->link);
651 if (!pdev)
652 return -ENODEV;
653
654 if (!pdev->is_physfn) {
655 pci_dev_put(pdev);
656 return -ENOSYS;
657 }
658
659 rc = sysfs_create_link(&dev->dev.kobj,
660 &pdev->dev.kobj, "dep_link");
661 pci_dev_put(pdev);
662 if (rc)
663 return rc;
664 }
665
666 iov->initial_VFs = initial;
667 if (nr_virtfn < initial)
668 initial = nr_virtfn;
669
670 rc = pcibios_sriov_enable(dev, initial);
671 if (rc) {
672 pci_err(dev, "failure %d from pcibios_sriov_enable()\n", rc);
673 goto err_pcibios;
674 }
675
676 pci_iov_set_numvfs(dev, nr_virtfn);
677 iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
678 pci_cfg_access_lock(dev);
679 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
680 msleep(100);
681 pci_cfg_access_unlock(dev);
682
683 rc = sriov_add_vfs(dev, initial);
684 if (rc)
685 goto err_pcibios;
686
687 kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE);
688 iov->num_VFs = nr_virtfn;
689
690 return 0;
691
692err_pcibios:
693 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
694 pci_cfg_access_lock(dev);
695 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
696 ssleep(1);
697 pci_cfg_access_unlock(dev);
698
699 pcibios_sriov_disable(dev);
700
701 if (iov->link != dev->devfn)
702 sysfs_remove_link(&dev->dev.kobj, "dep_link");
703
704 pci_iov_set_numvfs(dev, 0);
705 return rc;
706}
707
708static void sriov_del_vfs(struct pci_dev *dev)
709{
710 struct pci_sriov *iov = dev->sriov;
711 int i;
712
713 for (i = 0; i < iov->num_VFs; i++)
714 pci_iov_remove_virtfn(dev, i);
715}
716
717static void sriov_disable(struct pci_dev *dev)
718{
719 struct pci_sriov *iov = dev->sriov;
720
721 if (!iov->num_VFs)
722 return;
723
724 sriov_del_vfs(dev);
725 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
726 pci_cfg_access_lock(dev);
727 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
728 ssleep(1);
729 pci_cfg_access_unlock(dev);
730
731 pcibios_sriov_disable(dev);
732
733 if (iov->link != dev->devfn)
734 sysfs_remove_link(&dev->dev.kobj, "dep_link");
735
736 iov->num_VFs = 0;
737 pci_iov_set_numvfs(dev, 0);
738}
739
740static int sriov_init(struct pci_dev *dev, int pos)
741{
742 int i, bar64;
743 int rc;
744 int nres;
745 u32 pgsz;
746 u16 ctrl, total;
747 struct pci_sriov *iov;
748 struct resource *res;
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 /*
790 * If it is already FIXED, don't change it, something
791 * (perhaps EA or header fixups) wants it this way.
792 */
793 if (res->flags & IORESOURCE_PCI_FIXED)
794 bar64 = (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
795 else
796 bar64 = __pci_read_base(dev, pci_bar_unknown, res,
797 pos + PCI_SRIOV_BAR + i * 4);
798 if (!res->flags)
799 continue;
800 if (resource_size(res) & (PAGE_SIZE - 1)) {
801 rc = -EIO;
802 goto failed;
803 }
804 iov->barsz[i] = resource_size(res);
805 res->end = res->start + resource_size(res) * total - 1;
806 pci_info(dev, "VF(n) BAR%d space: %pR (contains BAR%d for %d VFs)\n",
807 i, res, i, total);
808 i += bar64;
809 nres++;
810 }
811
812 iov->pos = pos;
813 iov->nres = nres;
814 iov->ctrl = ctrl;
815 iov->total_VFs = total;
816 iov->driver_max_VFs = total;
817 pci_read_config_word(dev, pos + PCI_SRIOV_VF_DID, &iov->vf_device);
818 iov->pgsz = pgsz;
819 iov->self = dev;
820 iov->drivers_autoprobe = true;
821 pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap);
822 pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link);
823 if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END)
824 iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link);
825
826 if (pdev)
827 iov->dev = pci_dev_get(pdev);
828 else
829 iov->dev = dev;
830
831 dev->sriov = iov;
832 dev->is_physfn = 1;
833 rc = compute_max_vf_buses(dev);
834 if (rc)
835 goto fail_max_buses;
836
837 return 0;
838
839fail_max_buses:
840 dev->sriov = NULL;
841 dev->is_physfn = 0;
842failed:
843 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
844 res = &dev->resource[i + PCI_IOV_RESOURCES];
845 res->flags = 0;
846 }
847
848 kfree(iov);
849 return rc;
850}
851
852static void sriov_release(struct pci_dev *dev)
853{
854 BUG_ON(dev->sriov->num_VFs);
855
856 if (dev != dev->sriov->dev)
857 pci_dev_put(dev->sriov->dev);
858
859 kfree(dev->sriov);
860 dev->sriov = NULL;
861}
862
863static void sriov_restore_state(struct pci_dev *dev)
864{
865 int i;
866 u16 ctrl;
867 struct pci_sriov *iov = dev->sriov;
868
869 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl);
870 if (ctrl & PCI_SRIOV_CTRL_VFE)
871 return;
872
873 /*
874 * Restore PCI_SRIOV_CTRL_ARI before pci_iov_set_numvfs() because
875 * it reads offset & stride, which depend on PCI_SRIOV_CTRL_ARI.
876 */
877 ctrl &= ~PCI_SRIOV_CTRL_ARI;
878 ctrl |= iov->ctrl & PCI_SRIOV_CTRL_ARI;
879 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, ctrl);
880
881 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++)
882 pci_update_resource(dev, i + PCI_IOV_RESOURCES);
883
884 pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
885 pci_iov_set_numvfs(dev, iov->num_VFs);
886 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
887 if (iov->ctrl & PCI_SRIOV_CTRL_VFE)
888 msleep(100);
889}
890
891/**
892 * pci_iov_init - initialize the IOV capability
893 * @dev: the PCI device
894 *
895 * Returns 0 on success, or negative on failure.
896 */
897int pci_iov_init(struct pci_dev *dev)
898{
899 int pos;
900
901 if (!pci_is_pcie(dev))
902 return -ENODEV;
903
904 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV);
905 if (pos)
906 return sriov_init(dev, pos);
907
908 return -ENODEV;
909}
910
911/**
912 * pci_iov_release - release resources used by the IOV capability
913 * @dev: the PCI device
914 */
915void pci_iov_release(struct pci_dev *dev)
916{
917 if (dev->is_physfn)
918 sriov_release(dev);
919}
920
921/**
922 * pci_iov_remove - clean up SR-IOV state after PF driver is detached
923 * @dev: the PCI device
924 */
925void pci_iov_remove(struct pci_dev *dev)
926{
927 struct pci_sriov *iov = dev->sriov;
928
929 if (!dev->is_physfn)
930 return;
931
932 iov->driver_max_VFs = iov->total_VFs;
933 if (iov->num_VFs)
934 pci_warn(dev, "driver left SR-IOV enabled after remove\n");
935}
936
937/**
938 * pci_iov_update_resource - update a VF BAR
939 * @dev: the PCI device
940 * @resno: the resource number
941 *
942 * Update a VF BAR in the SR-IOV capability of a PF.
943 */
944void pci_iov_update_resource(struct pci_dev *dev, int resno)
945{
946 struct pci_sriov *iov = dev->is_physfn ? dev->sriov : NULL;
947 struct resource *res = dev->resource + resno;
948 int vf_bar = resno - PCI_IOV_RESOURCES;
949 struct pci_bus_region region;
950 u16 cmd;
951 u32 new;
952 int reg;
953
954 /*
955 * The generic pci_restore_bars() path calls this for all devices,
956 * including VFs and non-SR-IOV devices. If this is not a PF, we
957 * have nothing to do.
958 */
959 if (!iov)
960 return;
961
962 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &cmd);
963 if ((cmd & PCI_SRIOV_CTRL_VFE) && (cmd & PCI_SRIOV_CTRL_MSE)) {
964 dev_WARN(&dev->dev, "can't update enabled VF BAR%d %pR\n",
965 vf_bar, res);
966 return;
967 }
968
969 /*
970 * Ignore unimplemented BARs, unused resource slots for 64-bit
971 * BARs, and non-movable resources, e.g., those described via
972 * Enhanced Allocation.
973 */
974 if (!res->flags)
975 return;
976
977 if (res->flags & IORESOURCE_UNSET)
978 return;
979
980 if (res->flags & IORESOURCE_PCI_FIXED)
981 return;
982
983 pcibios_resource_to_bus(dev->bus, ®ion, res);
984 new = region.start;
985 new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK;
986
987 reg = iov->pos + PCI_SRIOV_BAR + 4 * vf_bar;
988 pci_write_config_dword(dev, reg, new);
989 if (res->flags & IORESOURCE_MEM_64) {
990 new = region.start >> 16 >> 16;
991 pci_write_config_dword(dev, reg + 4, new);
992 }
993}
994
995resource_size_t __weak pcibios_iov_resource_alignment(struct pci_dev *dev,
996 int resno)
997{
998 return pci_iov_resource_size(dev, resno);
999}
1000
1001/**
1002 * pci_sriov_resource_alignment - get resource alignment for VF BAR
1003 * @dev: the PCI device
1004 * @resno: the resource number
1005 *
1006 * Returns the alignment of the VF BAR found in the SR-IOV capability.
1007 * This is not the same as the resource size which is defined as
1008 * the VF BAR size multiplied by the number of VFs. The alignment
1009 * is just the VF BAR size.
1010 */
1011resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno)
1012{
1013 return pcibios_iov_resource_alignment(dev, resno);
1014}
1015
1016/**
1017 * pci_restore_iov_state - restore the state of the IOV capability
1018 * @dev: the PCI device
1019 */
1020void pci_restore_iov_state(struct pci_dev *dev)
1021{
1022 if (dev->is_physfn)
1023 sriov_restore_state(dev);
1024}
1025
1026/**
1027 * pci_vf_drivers_autoprobe - set PF property drivers_autoprobe for VFs
1028 * @dev: the PCI device
1029 * @auto_probe: set VF drivers auto probe flag
1030 */
1031void pci_vf_drivers_autoprobe(struct pci_dev *dev, bool auto_probe)
1032{
1033 if (dev->is_physfn)
1034 dev->sriov->drivers_autoprobe = auto_probe;
1035}
1036
1037/**
1038 * pci_iov_bus_range - find bus range used by Virtual Function
1039 * @bus: the PCI bus
1040 *
1041 * Returns max number of buses (exclude current one) used by Virtual
1042 * Functions.
1043 */
1044int pci_iov_bus_range(struct pci_bus *bus)
1045{
1046 int max = 0;
1047 struct pci_dev *dev;
1048
1049 list_for_each_entry(dev, &bus->devices, bus_list) {
1050 if (!dev->is_physfn)
1051 continue;
1052 if (dev->sriov->max_VF_buses > max)
1053 max = dev->sriov->max_VF_buses;
1054 }
1055
1056 return max ? max - bus->number : 0;
1057}
1058
1059/**
1060 * pci_enable_sriov - enable the SR-IOV capability
1061 * @dev: the PCI device
1062 * @nr_virtfn: number of virtual functions to enable
1063 *
1064 * Returns 0 on success, or negative on failure.
1065 */
1066int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
1067{
1068 might_sleep();
1069
1070 if (!dev->is_physfn)
1071 return -ENOSYS;
1072
1073 return sriov_enable(dev, nr_virtfn);
1074}
1075EXPORT_SYMBOL_GPL(pci_enable_sriov);
1076
1077/**
1078 * pci_disable_sriov - disable the SR-IOV capability
1079 * @dev: the PCI device
1080 */
1081void pci_disable_sriov(struct pci_dev *dev)
1082{
1083 might_sleep();
1084
1085 if (!dev->is_physfn)
1086 return;
1087
1088 sriov_disable(dev);
1089}
1090EXPORT_SYMBOL_GPL(pci_disable_sriov);
1091
1092/**
1093 * pci_num_vf - return number of VFs associated with a PF device_release_driver
1094 * @dev: the PCI device
1095 *
1096 * Returns number of VFs, or 0 if SR-IOV is not enabled.
1097 */
1098int pci_num_vf(struct pci_dev *dev)
1099{
1100 if (!dev->is_physfn)
1101 return 0;
1102
1103 return dev->sriov->num_VFs;
1104}
1105EXPORT_SYMBOL_GPL(pci_num_vf);
1106
1107/**
1108 * pci_vfs_assigned - returns number of VFs are assigned to a guest
1109 * @dev: the PCI device
1110 *
1111 * Returns number of VFs belonging to this device that are assigned to a guest.
1112 * If device is not a physical function returns 0.
1113 */
1114int pci_vfs_assigned(struct pci_dev *dev)
1115{
1116 struct pci_dev *vfdev;
1117 unsigned int vfs_assigned = 0;
1118 unsigned short dev_id;
1119
1120 /* only search if we are a PF */
1121 if (!dev->is_physfn)
1122 return 0;
1123
1124 /*
1125 * determine the device ID for the VFs, the vendor ID will be the
1126 * same as the PF so there is no need to check for that one
1127 */
1128 dev_id = dev->sriov->vf_device;
1129
1130 /* loop through all the VFs to see if we own any that are assigned */
1131 vfdev = pci_get_device(dev->vendor, dev_id, NULL);
1132 while (vfdev) {
1133 /*
1134 * It is considered assigned if it is a virtual function with
1135 * our dev as the physical function and the assigned bit is set
1136 */
1137 if (vfdev->is_virtfn && (vfdev->physfn == dev) &&
1138 pci_is_dev_assigned(vfdev))
1139 vfs_assigned++;
1140
1141 vfdev = pci_get_device(dev->vendor, dev_id, vfdev);
1142 }
1143
1144 return vfs_assigned;
1145}
1146EXPORT_SYMBOL_GPL(pci_vfs_assigned);
1147
1148/**
1149 * pci_sriov_set_totalvfs -- reduce the TotalVFs available
1150 * @dev: the PCI PF device
1151 * @numvfs: number that should be used for TotalVFs supported
1152 *
1153 * Should be called from PF driver's probe routine with
1154 * device's mutex held.
1155 *
1156 * Returns 0 if PF is an SRIOV-capable device and
1157 * value of numvfs valid. If not a PF return -ENOSYS;
1158 * if numvfs is invalid return -EINVAL;
1159 * if VFs already enabled, return -EBUSY.
1160 */
1161int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs)
1162{
1163 if (!dev->is_physfn)
1164 return -ENOSYS;
1165
1166 if (numvfs > dev->sriov->total_VFs)
1167 return -EINVAL;
1168
1169 /* Shouldn't change if VFs already enabled */
1170 if (dev->sriov->ctrl & PCI_SRIOV_CTRL_VFE)
1171 return -EBUSY;
1172
1173 dev->sriov->driver_max_VFs = numvfs;
1174 return 0;
1175}
1176EXPORT_SYMBOL_GPL(pci_sriov_set_totalvfs);
1177
1178/**
1179 * pci_sriov_get_totalvfs -- get total VFs supported on this device
1180 * @dev: the PCI PF device
1181 *
1182 * For a PCIe device with SRIOV support, return the PCIe
1183 * SRIOV capability value of TotalVFs or the value of driver_max_VFs
1184 * if the driver reduced it. Otherwise 0.
1185 */
1186int pci_sriov_get_totalvfs(struct pci_dev *dev)
1187{
1188 if (!dev->is_physfn)
1189 return 0;
1190
1191 return dev->sriov->driver_max_VFs;
1192}
1193EXPORT_SYMBOL_GPL(pci_sriov_get_totalvfs);
1194
1195/**
1196 * pci_sriov_configure_simple - helper to configure SR-IOV
1197 * @dev: the PCI device
1198 * @nr_virtfn: number of virtual functions to enable, 0 to disable
1199 *
1200 * Enable or disable SR-IOV for devices that don't require any PF setup
1201 * before enabling SR-IOV. Return value is negative on error, or number of
1202 * VFs allocated on success.
1203 */
1204int pci_sriov_configure_simple(struct pci_dev *dev, int nr_virtfn)
1205{
1206 int rc;
1207
1208 might_sleep();
1209
1210 if (!dev->is_physfn)
1211 return -ENODEV;
1212
1213 if (pci_vfs_assigned(dev)) {
1214 pci_warn(dev, "Cannot modify SR-IOV while VFs are assigned\n");
1215 return -EPERM;
1216 }
1217
1218 if (nr_virtfn == 0) {
1219 sriov_disable(dev);
1220 return 0;
1221 }
1222
1223 rc = sriov_enable(dev, nr_virtfn);
1224 if (rc < 0)
1225 return rc;
1226
1227 return nr_virtfn;
1228}
1229EXPORT_SYMBOL_GPL(pci_sriov_configure_simple);
1/*
2 * drivers/pci/iov.c
3 *
4 * Copyright (C) 2009 Intel Corporation, Yu Zhao <yu.zhao@intel.com>
5 *
6 * PCI Express I/O Virtualization (IOV) support.
7 * Single Root IOV 1.0
8 * Address Translation Service 1.0
9 */
10
11#include <linux/pci.h>
12#include <linux/slab.h>
13#include <linux/mutex.h>
14#include <linux/export.h>
15#include <linux/string.h>
16#include <linux/delay.h>
17#include <linux/pci-ats.h>
18#include "pci.h"
19
20#define VIRTFN_ID_LEN 16
21
22int pci_iov_virtfn_bus(struct pci_dev *dev, int vf_id)
23{
24 if (!dev->is_physfn)
25 return -EINVAL;
26 return dev->bus->number + ((dev->devfn + dev->sriov->offset +
27 dev->sriov->stride * vf_id) >> 8);
28}
29
30int pci_iov_virtfn_devfn(struct pci_dev *dev, int vf_id)
31{
32 if (!dev->is_physfn)
33 return -EINVAL;
34 return (dev->devfn + dev->sriov->offset +
35 dev->sriov->stride * vf_id) & 0xff;
36}
37
38/*
39 * Per SR-IOV spec sec 3.3.10 and 3.3.11, First VF Offset and VF Stride may
40 * change when NumVFs changes.
41 *
42 * Update iov->offset and iov->stride when NumVFs is written.
43 */
44static inline void pci_iov_set_numvfs(struct pci_dev *dev, int nr_virtfn)
45{
46 struct pci_sriov *iov = dev->sriov;
47
48 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn);
49 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &iov->offset);
50 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &iov->stride);
51}
52
53/*
54 * The PF consumes one bus number. NumVFs, First VF Offset, and VF Stride
55 * determine how many additional bus numbers will be consumed by VFs.
56 *
57 * Iterate over all valid NumVFs, validate offset and stride, and calculate
58 * the maximum number of bus numbers that could ever be required.
59 */
60static int compute_max_vf_buses(struct pci_dev *dev)
61{
62 struct pci_sriov *iov = dev->sriov;
63 int nr_virtfn, busnr, rc = 0;
64
65 for (nr_virtfn = iov->total_VFs; nr_virtfn; nr_virtfn--) {
66 pci_iov_set_numvfs(dev, nr_virtfn);
67 if (!iov->offset || (nr_virtfn > 1 && !iov->stride)) {
68 rc = -EIO;
69 goto out;
70 }
71
72 busnr = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
73 if (busnr > iov->max_VF_buses)
74 iov->max_VF_buses = busnr;
75 }
76
77out:
78 pci_iov_set_numvfs(dev, 0);
79 return rc;
80}
81
82static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr)
83{
84 struct pci_bus *child;
85
86 if (bus->number == busnr)
87 return bus;
88
89 child = pci_find_bus(pci_domain_nr(bus), busnr);
90 if (child)
91 return child;
92
93 child = pci_add_new_bus(bus, NULL, busnr);
94 if (!child)
95 return NULL;
96
97 pci_bus_insert_busn_res(child, busnr, busnr);
98
99 return child;
100}
101
102static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus)
103{
104 if (physbus != virtbus && list_empty(&virtbus->devices))
105 pci_remove_bus(virtbus);
106}
107
108resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)
109{
110 if (!dev->is_physfn)
111 return 0;
112
113 return dev->sriov->barsz[resno - PCI_IOV_RESOURCES];
114}
115
116int pci_iov_add_virtfn(struct pci_dev *dev, int id, int reset)
117{
118 int i;
119 int rc = -ENOMEM;
120 u64 size;
121 char buf[VIRTFN_ID_LEN];
122 struct pci_dev *virtfn;
123 struct resource *res;
124 struct pci_sriov *iov = dev->sriov;
125 struct pci_bus *bus;
126
127 mutex_lock(&iov->dev->sriov->lock);
128 bus = virtfn_add_bus(dev->bus, pci_iov_virtfn_bus(dev, id));
129 if (!bus)
130 goto failed;
131
132 virtfn = pci_alloc_dev(bus);
133 if (!virtfn)
134 goto failed0;
135
136 virtfn->devfn = pci_iov_virtfn_devfn(dev, id);
137 virtfn->vendor = dev->vendor;
138 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_DID, &virtfn->device);
139 pci_setup_device(virtfn);
140 virtfn->dev.parent = dev->dev.parent;
141 virtfn->physfn = pci_dev_get(dev);
142 virtfn->is_virtfn = 1;
143 virtfn->multifunction = 0;
144
145 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
146 res = &dev->resource[i + PCI_IOV_RESOURCES];
147 if (!res->parent)
148 continue;
149 virtfn->resource[i].name = pci_name(virtfn);
150 virtfn->resource[i].flags = res->flags;
151 size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);
152 virtfn->resource[i].start = res->start + size * id;
153 virtfn->resource[i].end = virtfn->resource[i].start + size - 1;
154 rc = request_resource(res, &virtfn->resource[i]);
155 BUG_ON(rc);
156 }
157
158 if (reset)
159 __pci_reset_function(virtfn);
160
161 pci_device_add(virtfn, virtfn->bus);
162 mutex_unlock(&iov->dev->sriov->lock);
163
164 pci_bus_add_device(virtfn);
165 sprintf(buf, "virtfn%u", id);
166 rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
167 if (rc)
168 goto failed1;
169 rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");
170 if (rc)
171 goto failed2;
172
173 kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);
174
175 return 0;
176
177failed2:
178 sysfs_remove_link(&dev->dev.kobj, buf);
179failed1:
180 pci_dev_put(dev);
181 mutex_lock(&iov->dev->sriov->lock);
182 pci_stop_and_remove_bus_device(virtfn);
183failed0:
184 virtfn_remove_bus(dev->bus, bus);
185failed:
186 mutex_unlock(&iov->dev->sriov->lock);
187
188 return rc;
189}
190
191void pci_iov_remove_virtfn(struct pci_dev *dev, int id, int reset)
192{
193 char buf[VIRTFN_ID_LEN];
194 struct pci_dev *virtfn;
195 struct pci_sriov *iov = dev->sriov;
196
197 virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus),
198 pci_iov_virtfn_bus(dev, id),
199 pci_iov_virtfn_devfn(dev, id));
200 if (!virtfn)
201 return;
202
203 if (reset) {
204 device_release_driver(&virtfn->dev);
205 __pci_reset_function(virtfn);
206 }
207
208 sprintf(buf, "virtfn%u", id);
209 sysfs_remove_link(&dev->dev.kobj, buf);
210 /*
211 * pci_stop_dev() could have been called for this virtfn already,
212 * so the directory for the virtfn may have been removed before.
213 * Double check to avoid spurious sysfs warnings.
214 */
215 if (virtfn->dev.kobj.sd)
216 sysfs_remove_link(&virtfn->dev.kobj, "physfn");
217
218 mutex_lock(&iov->dev->sriov->lock);
219 pci_stop_and_remove_bus_device(virtfn);
220 virtfn_remove_bus(dev->bus, virtfn->bus);
221 mutex_unlock(&iov->dev->sriov->lock);
222
223 /* balance pci_get_domain_bus_and_slot() */
224 pci_dev_put(virtfn);
225 pci_dev_put(dev);
226}
227
228int __weak pcibios_sriov_enable(struct pci_dev *pdev, u16 num_vfs)
229{
230 return 0;
231}
232
233int __weak pcibios_sriov_disable(struct pci_dev *pdev)
234{
235 return 0;
236}
237
238static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
239{
240 int rc;
241 int i;
242 int nres;
243 u16 initial;
244 struct resource *res;
245 struct pci_dev *pdev;
246 struct pci_sriov *iov = dev->sriov;
247 int bars = 0;
248 int bus;
249
250 if (!nr_virtfn)
251 return 0;
252
253 if (iov->num_VFs)
254 return -EINVAL;
255
256 pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial);
257 if (initial > iov->total_VFs ||
258 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total_VFs)))
259 return -EIO;
260
261 if (nr_virtfn < 0 || nr_virtfn > iov->total_VFs ||
262 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
263 return -EINVAL;
264
265 nres = 0;
266 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
267 bars |= (1 << (i + PCI_IOV_RESOURCES));
268 res = &dev->resource[i + PCI_IOV_RESOURCES];
269 if (res->parent)
270 nres++;
271 }
272 if (nres != iov->nres) {
273 dev_err(&dev->dev, "not enough MMIO resources for SR-IOV\n");
274 return -ENOMEM;
275 }
276
277 bus = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
278 if (bus > dev->bus->busn_res.end) {
279 dev_err(&dev->dev, "can't enable %d VFs (bus %02x out of range of %pR)\n",
280 nr_virtfn, bus, &dev->bus->busn_res);
281 return -ENOMEM;
282 }
283
284 if (pci_enable_resources(dev, bars)) {
285 dev_err(&dev->dev, "SR-IOV: IOV BARS not allocated\n");
286 return -ENOMEM;
287 }
288
289 if (iov->link != dev->devfn) {
290 pdev = pci_get_slot(dev->bus, iov->link);
291 if (!pdev)
292 return -ENODEV;
293
294 if (!pdev->is_physfn) {
295 pci_dev_put(pdev);
296 return -ENOSYS;
297 }
298
299 rc = sysfs_create_link(&dev->dev.kobj,
300 &pdev->dev.kobj, "dep_link");
301 pci_dev_put(pdev);
302 if (rc)
303 return rc;
304 }
305
306 pci_iov_set_numvfs(dev, nr_virtfn);
307 iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
308 pci_cfg_access_lock(dev);
309 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
310 msleep(100);
311 pci_cfg_access_unlock(dev);
312
313 iov->initial_VFs = initial;
314 if (nr_virtfn < initial)
315 initial = nr_virtfn;
316
317 rc = pcibios_sriov_enable(dev, initial);
318 if (rc) {
319 dev_err(&dev->dev, "failure %d from pcibios_sriov_enable()\n", rc);
320 goto err_pcibios;
321 }
322
323 for (i = 0; i < initial; i++) {
324 rc = pci_iov_add_virtfn(dev, i, 0);
325 if (rc)
326 goto failed;
327 }
328
329 kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE);
330 iov->num_VFs = nr_virtfn;
331
332 return 0;
333
334failed:
335 while (i--)
336 pci_iov_remove_virtfn(dev, i, 0);
337
338 pcibios_sriov_disable(dev);
339err_pcibios:
340 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
341 pci_cfg_access_lock(dev);
342 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
343 ssleep(1);
344 pci_cfg_access_unlock(dev);
345
346 if (iov->link != dev->devfn)
347 sysfs_remove_link(&dev->dev.kobj, "dep_link");
348
349 pci_iov_set_numvfs(dev, 0);
350 return rc;
351}
352
353static void sriov_disable(struct pci_dev *dev)
354{
355 int i;
356 struct pci_sriov *iov = dev->sriov;
357
358 if (!iov->num_VFs)
359 return;
360
361 for (i = 0; i < iov->num_VFs; i++)
362 pci_iov_remove_virtfn(dev, i, 0);
363
364 pcibios_sriov_disable(dev);
365
366 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
367 pci_cfg_access_lock(dev);
368 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
369 ssleep(1);
370 pci_cfg_access_unlock(dev);
371
372 if (iov->link != dev->devfn)
373 sysfs_remove_link(&dev->dev.kobj, "dep_link");
374
375 iov->num_VFs = 0;
376 pci_iov_set_numvfs(dev, 0);
377}
378
379static int sriov_init(struct pci_dev *dev, int pos)
380{
381 int i, bar64;
382 int rc;
383 int nres;
384 u32 pgsz;
385 u16 ctrl, total;
386 struct pci_sriov *iov;
387 struct resource *res;
388 struct pci_dev *pdev;
389
390 pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl);
391 if (ctrl & PCI_SRIOV_CTRL_VFE) {
392 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0);
393 ssleep(1);
394 }
395
396 ctrl = 0;
397 list_for_each_entry(pdev, &dev->bus->devices, bus_list)
398 if (pdev->is_physfn)
399 goto found;
400
401 pdev = NULL;
402 if (pci_ari_enabled(dev->bus))
403 ctrl |= PCI_SRIOV_CTRL_ARI;
404
405found:
406 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl);
407
408 pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total);
409 if (!total)
410 return 0;
411
412 pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz);
413 i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0;
414 pgsz &= ~((1 << i) - 1);
415 if (!pgsz)
416 return -EIO;
417
418 pgsz &= ~(pgsz - 1);
419 pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz);
420
421 iov = kzalloc(sizeof(*iov), GFP_KERNEL);
422 if (!iov)
423 return -ENOMEM;
424
425 nres = 0;
426 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
427 res = &dev->resource[i + PCI_IOV_RESOURCES];
428 /*
429 * If it is already FIXED, don't change it, something
430 * (perhaps EA or header fixups) wants it this way.
431 */
432 if (res->flags & IORESOURCE_PCI_FIXED)
433 bar64 = (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
434 else
435 bar64 = __pci_read_base(dev, pci_bar_unknown, res,
436 pos + PCI_SRIOV_BAR + i * 4);
437 if (!res->flags)
438 continue;
439 if (resource_size(res) & (PAGE_SIZE - 1)) {
440 rc = -EIO;
441 goto failed;
442 }
443 iov->barsz[i] = resource_size(res);
444 res->end = res->start + resource_size(res) * total - 1;
445 dev_info(&dev->dev, "VF(n) BAR%d space: %pR (contains BAR%d for %d VFs)\n",
446 i, res, i, total);
447 i += bar64;
448 nres++;
449 }
450
451 iov->pos = pos;
452 iov->nres = nres;
453 iov->ctrl = ctrl;
454 iov->total_VFs = total;
455 iov->pgsz = pgsz;
456 iov->self = dev;
457 pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap);
458 pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link);
459 if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END)
460 iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link);
461
462 if (pdev)
463 iov->dev = pci_dev_get(pdev);
464 else
465 iov->dev = dev;
466
467 mutex_init(&iov->lock);
468
469 dev->sriov = iov;
470 dev->is_physfn = 1;
471 rc = compute_max_vf_buses(dev);
472 if (rc)
473 goto fail_max_buses;
474
475 return 0;
476
477fail_max_buses:
478 dev->sriov = NULL;
479 dev->is_physfn = 0;
480failed:
481 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
482 res = &dev->resource[i + PCI_IOV_RESOURCES];
483 res->flags = 0;
484 }
485
486 kfree(iov);
487 return rc;
488}
489
490static void sriov_release(struct pci_dev *dev)
491{
492 BUG_ON(dev->sriov->num_VFs);
493
494 if (dev != dev->sriov->dev)
495 pci_dev_put(dev->sriov->dev);
496
497 mutex_destroy(&dev->sriov->lock);
498
499 kfree(dev->sriov);
500 dev->sriov = NULL;
501}
502
503static void sriov_restore_state(struct pci_dev *dev)
504{
505 int i;
506 u16 ctrl;
507 struct pci_sriov *iov = dev->sriov;
508
509 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl);
510 if (ctrl & PCI_SRIOV_CTRL_VFE)
511 return;
512
513 for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++)
514 pci_update_resource(dev, i);
515
516 pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
517 pci_iov_set_numvfs(dev, iov->num_VFs);
518 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
519 if (iov->ctrl & PCI_SRIOV_CTRL_VFE)
520 msleep(100);
521}
522
523/**
524 * pci_iov_init - initialize the IOV capability
525 * @dev: the PCI device
526 *
527 * Returns 0 on success, or negative on failure.
528 */
529int pci_iov_init(struct pci_dev *dev)
530{
531 int pos;
532
533 if (!pci_is_pcie(dev))
534 return -ENODEV;
535
536 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV);
537 if (pos)
538 return sriov_init(dev, pos);
539
540 return -ENODEV;
541}
542
543/**
544 * pci_iov_release - release resources used by the IOV capability
545 * @dev: the PCI device
546 */
547void pci_iov_release(struct pci_dev *dev)
548{
549 if (dev->is_physfn)
550 sriov_release(dev);
551}
552
553/**
554 * pci_iov_resource_bar - get position of the SR-IOV BAR
555 * @dev: the PCI device
556 * @resno: the resource number
557 *
558 * Returns position of the BAR encapsulated in the SR-IOV capability.
559 */
560int pci_iov_resource_bar(struct pci_dev *dev, int resno)
561{
562 if (resno < PCI_IOV_RESOURCES || resno > PCI_IOV_RESOURCE_END)
563 return 0;
564
565 BUG_ON(!dev->is_physfn);
566
567 return dev->sriov->pos + PCI_SRIOV_BAR +
568 4 * (resno - PCI_IOV_RESOURCES);
569}
570
571resource_size_t __weak pcibios_iov_resource_alignment(struct pci_dev *dev,
572 int resno)
573{
574 return pci_iov_resource_size(dev, resno);
575}
576
577/**
578 * pci_sriov_resource_alignment - get resource alignment for VF BAR
579 * @dev: the PCI device
580 * @resno: the resource number
581 *
582 * Returns the alignment of the VF BAR found in the SR-IOV capability.
583 * This is not the same as the resource size which is defined as
584 * the VF BAR size multiplied by the number of VFs. The alignment
585 * is just the VF BAR size.
586 */
587resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno)
588{
589 return pcibios_iov_resource_alignment(dev, resno);
590}
591
592/**
593 * pci_restore_iov_state - restore the state of the IOV capability
594 * @dev: the PCI device
595 */
596void pci_restore_iov_state(struct pci_dev *dev)
597{
598 if (dev->is_physfn)
599 sriov_restore_state(dev);
600}
601
602/**
603 * pci_iov_bus_range - find bus range used by Virtual Function
604 * @bus: the PCI bus
605 *
606 * Returns max number of buses (exclude current one) used by Virtual
607 * Functions.
608 */
609int pci_iov_bus_range(struct pci_bus *bus)
610{
611 int max = 0;
612 struct pci_dev *dev;
613
614 list_for_each_entry(dev, &bus->devices, bus_list) {
615 if (!dev->is_physfn)
616 continue;
617 if (dev->sriov->max_VF_buses > max)
618 max = dev->sriov->max_VF_buses;
619 }
620
621 return max ? max - bus->number : 0;
622}
623
624/**
625 * pci_enable_sriov - enable the SR-IOV capability
626 * @dev: the PCI device
627 * @nr_virtfn: number of virtual functions to enable
628 *
629 * Returns 0 on success, or negative on failure.
630 */
631int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
632{
633 might_sleep();
634
635 if (!dev->is_physfn)
636 return -ENOSYS;
637
638 return sriov_enable(dev, nr_virtfn);
639}
640EXPORT_SYMBOL_GPL(pci_enable_sriov);
641
642/**
643 * pci_disable_sriov - disable the SR-IOV capability
644 * @dev: the PCI device
645 */
646void pci_disable_sriov(struct pci_dev *dev)
647{
648 might_sleep();
649
650 if (!dev->is_physfn)
651 return;
652
653 sriov_disable(dev);
654}
655EXPORT_SYMBOL_GPL(pci_disable_sriov);
656
657/**
658 * pci_num_vf - return number of VFs associated with a PF device_release_driver
659 * @dev: the PCI device
660 *
661 * Returns number of VFs, or 0 if SR-IOV is not enabled.
662 */
663int pci_num_vf(struct pci_dev *dev)
664{
665 if (!dev->is_physfn)
666 return 0;
667
668 return dev->sriov->num_VFs;
669}
670EXPORT_SYMBOL_GPL(pci_num_vf);
671
672/**
673 * pci_vfs_assigned - returns number of VFs are assigned to a guest
674 * @dev: the PCI device
675 *
676 * Returns number of VFs belonging to this device that are assigned to a guest.
677 * If device is not a physical function returns 0.
678 */
679int pci_vfs_assigned(struct pci_dev *dev)
680{
681 struct pci_dev *vfdev;
682 unsigned int vfs_assigned = 0;
683 unsigned short dev_id;
684
685 /* only search if we are a PF */
686 if (!dev->is_physfn)
687 return 0;
688
689 /*
690 * determine the device ID for the VFs, the vendor ID will be the
691 * same as the PF so there is no need to check for that one
692 */
693 pci_read_config_word(dev, dev->sriov->pos + PCI_SRIOV_VF_DID, &dev_id);
694
695 /* loop through all the VFs to see if we own any that are assigned */
696 vfdev = pci_get_device(dev->vendor, dev_id, NULL);
697 while (vfdev) {
698 /*
699 * It is considered assigned if it is a virtual function with
700 * our dev as the physical function and the assigned bit is set
701 */
702 if (vfdev->is_virtfn && (vfdev->physfn == dev) &&
703 pci_is_dev_assigned(vfdev))
704 vfs_assigned++;
705
706 vfdev = pci_get_device(dev->vendor, dev_id, vfdev);
707 }
708
709 return vfs_assigned;
710}
711EXPORT_SYMBOL_GPL(pci_vfs_assigned);
712
713/**
714 * pci_sriov_set_totalvfs -- reduce the TotalVFs available
715 * @dev: the PCI PF device
716 * @numvfs: number that should be used for TotalVFs supported
717 *
718 * Should be called from PF driver's probe routine with
719 * device's mutex held.
720 *
721 * Returns 0 if PF is an SRIOV-capable device and
722 * value of numvfs valid. If not a PF return -ENOSYS;
723 * if numvfs is invalid return -EINVAL;
724 * if VFs already enabled, return -EBUSY.
725 */
726int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs)
727{
728 if (!dev->is_physfn)
729 return -ENOSYS;
730 if (numvfs > dev->sriov->total_VFs)
731 return -EINVAL;
732
733 /* Shouldn't change if VFs already enabled */
734 if (dev->sriov->ctrl & PCI_SRIOV_CTRL_VFE)
735 return -EBUSY;
736 else
737 dev->sriov->driver_max_VFs = numvfs;
738
739 return 0;
740}
741EXPORT_SYMBOL_GPL(pci_sriov_set_totalvfs);
742
743/**
744 * pci_sriov_get_totalvfs -- get total VFs supported on this device
745 * @dev: the PCI PF device
746 *
747 * For a PCIe device with SRIOV support, return the PCIe
748 * SRIOV capability value of TotalVFs or the value of driver_max_VFs
749 * if the driver reduced it. Otherwise 0.
750 */
751int pci_sriov_get_totalvfs(struct pci_dev *dev)
752{
753 if (!dev->is_physfn)
754 return 0;
755
756 if (dev->sriov->driver_max_VFs)
757 return dev->sriov->driver_max_VFs;
758
759 return dev->sriov->total_VFs;
760}
761EXPORT_SYMBOL_GPL(pci_sriov_get_totalvfs);