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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 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/mutex.h>
13#include <linux/export.h>
14#include <linux/string.h>
15#include <linux/delay.h>
16#include <linux/pci-ats.h>
17#include "pci.h"
18
19#define VIRTFN_ID_LEN 16
20
21int pci_iov_virtfn_bus(struct pci_dev *dev, int vf_id)
22{
23 if (!dev->is_physfn)
24 return -EINVAL;
25 return dev->bus->number + ((dev->devfn + dev->sriov->offset +
26 dev->sriov->stride * vf_id) >> 8);
27}
28
29int pci_iov_virtfn_devfn(struct pci_dev *dev, int vf_id)
30{
31 if (!dev->is_physfn)
32 return -EINVAL;
33 return (dev->devfn + dev->sriov->offset +
34 dev->sriov->stride * vf_id) & 0xff;
35}
36
37/*
38 * Per SR-IOV spec sec 3.3.10 and 3.3.11, First VF Offset and VF Stride may
39 * change when NumVFs changes.
40 *
41 * Update iov->offset and iov->stride when NumVFs is written.
42 */
43static inline void pci_iov_set_numvfs(struct pci_dev *dev, int nr_virtfn)
44{
45 struct pci_sriov *iov = dev->sriov;
46
47 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn);
48 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &iov->offset);
49 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &iov->stride);
50}
51
52/*
53 * The PF consumes one bus number. NumVFs, First VF Offset, and VF Stride
54 * determine how many additional bus numbers will be consumed by VFs.
55 *
56 * Iterate over all valid NumVFs, validate offset and stride, and calculate
57 * the maximum number of bus numbers that could ever be required.
58 */
59static int compute_max_vf_buses(struct pci_dev *dev)
60{
61 struct pci_sriov *iov = dev->sriov;
62 int nr_virtfn, busnr, rc = 0;
63
64 for (nr_virtfn = iov->total_VFs; nr_virtfn; nr_virtfn--) {
65 pci_iov_set_numvfs(dev, nr_virtfn);
66 if (!iov->offset || (nr_virtfn > 1 && !iov->stride)) {
67 rc = -EIO;
68 goto out;
69 }
70
71 busnr = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
72 if (busnr > iov->max_VF_buses)
73 iov->max_VF_buses = busnr;
74 }
75
76out:
77 pci_iov_set_numvfs(dev, 0);
78 return rc;
79}
80
81static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr)
82{
83 struct pci_bus *child;
84
85 if (bus->number == busnr)
86 return bus;
87
88 child = pci_find_bus(pci_domain_nr(bus), busnr);
89 if (child)
90 return child;
91
92 child = pci_add_new_bus(bus, NULL, busnr);
93 if (!child)
94 return NULL;
95
96 pci_bus_insert_busn_res(child, busnr, busnr);
97
98 return child;
99}
100
101static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus)
102{
103 if (physbus != virtbus && list_empty(&virtbus->devices))
104 pci_remove_bus(virtbus);
105}
106
107resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)
108{
109 if (!dev->is_physfn)
110 return 0;
111
112 return dev->sriov->barsz[resno - PCI_IOV_RESOURCES];
113}
114
115static void pci_read_vf_config_common(struct pci_dev *virtfn)
116{
117 struct pci_dev *physfn = virtfn->physfn;
118
119 /*
120 * Some config registers are the same across all associated VFs.
121 * Read them once from VF0 so we can skip reading them from the
122 * other VFs.
123 *
124 * PCIe r4.0, sec 9.3.4.1, technically doesn't require all VFs to
125 * have the same Revision ID and Subsystem ID, but we assume they
126 * do.
127 */
128 pci_read_config_dword(virtfn, PCI_CLASS_REVISION,
129 &physfn->sriov->class);
130 pci_read_config_byte(virtfn, PCI_HEADER_TYPE,
131 &physfn->sriov->hdr_type);
132 pci_read_config_word(virtfn, PCI_SUBSYSTEM_VENDOR_ID,
133 &physfn->sriov->subsystem_vendor);
134 pci_read_config_word(virtfn, PCI_SUBSYSTEM_ID,
135 &physfn->sriov->subsystem_device);
136}
137
138int pci_iov_add_virtfn(struct pci_dev *dev, int id)
139{
140 int i;
141 int rc = -ENOMEM;
142 u64 size;
143 char buf[VIRTFN_ID_LEN];
144 struct pci_dev *virtfn;
145 struct resource *res;
146 struct pci_sriov *iov = dev->sriov;
147 struct pci_bus *bus;
148
149 bus = virtfn_add_bus(dev->bus, pci_iov_virtfn_bus(dev, id));
150 if (!bus)
151 goto failed;
152
153 virtfn = pci_alloc_dev(bus);
154 if (!virtfn)
155 goto failed0;
156
157 virtfn->devfn = pci_iov_virtfn_devfn(dev, id);
158 virtfn->vendor = dev->vendor;
159 virtfn->device = iov->vf_device;
160 virtfn->is_virtfn = 1;
161 virtfn->physfn = pci_dev_get(dev);
162
163 if (id == 0)
164 pci_read_vf_config_common(virtfn);
165
166 rc = pci_setup_device(virtfn);
167 if (rc)
168 goto failed1;
169
170 virtfn->dev.parent = dev->dev.parent;
171 virtfn->multifunction = 0;
172
173 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
174 res = &dev->resource[i + PCI_IOV_RESOURCES];
175 if (!res->parent)
176 continue;
177 virtfn->resource[i].name = pci_name(virtfn);
178 virtfn->resource[i].flags = res->flags;
179 size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);
180 virtfn->resource[i].start = res->start + size * id;
181 virtfn->resource[i].end = virtfn->resource[i].start + size - 1;
182 rc = request_resource(res, &virtfn->resource[i]);
183 BUG_ON(rc);
184 }
185
186 pci_device_add(virtfn, virtfn->bus);
187
188 sprintf(buf, "virtfn%u", id);
189 rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
190 if (rc)
191 goto failed2;
192 rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");
193 if (rc)
194 goto failed3;
195
196 kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);
197
198 pci_bus_add_device(virtfn);
199
200 return 0;
201
202failed3:
203 sysfs_remove_link(&dev->dev.kobj, buf);
204failed2:
205 pci_stop_and_remove_bus_device(virtfn);
206failed1:
207 pci_dev_put(dev);
208failed0:
209 virtfn_remove_bus(dev->bus, bus);
210failed:
211
212 return rc;
213}
214
215void pci_iov_remove_virtfn(struct pci_dev *dev, int id)
216{
217 char buf[VIRTFN_ID_LEN];
218 struct pci_dev *virtfn;
219
220 virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus),
221 pci_iov_virtfn_bus(dev, id),
222 pci_iov_virtfn_devfn(dev, id));
223 if (!virtfn)
224 return;
225
226 sprintf(buf, "virtfn%u", id);
227 sysfs_remove_link(&dev->dev.kobj, buf);
228 /*
229 * pci_stop_dev() could have been called for this virtfn already,
230 * so the directory for the virtfn may have been removed before.
231 * Double check to avoid spurious sysfs warnings.
232 */
233 if (virtfn->dev.kobj.sd)
234 sysfs_remove_link(&virtfn->dev.kobj, "physfn");
235
236 pci_stop_and_remove_bus_device(virtfn);
237 virtfn_remove_bus(dev->bus, virtfn->bus);
238
239 /* balance pci_get_domain_bus_and_slot() */
240 pci_dev_put(virtfn);
241 pci_dev_put(dev);
242}
243
244int __weak pcibios_sriov_enable(struct pci_dev *pdev, u16 num_vfs)
245{
246 return 0;
247}
248
249int __weak pcibios_sriov_disable(struct pci_dev *pdev)
250{
251 return 0;
252}
253
254static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
255{
256 int rc;
257 int i;
258 int nres;
259 u16 initial;
260 struct resource *res;
261 struct pci_dev *pdev;
262 struct pci_sriov *iov = dev->sriov;
263 int bars = 0;
264 int bus;
265
266 if (!nr_virtfn)
267 return 0;
268
269 if (iov->num_VFs)
270 return -EINVAL;
271
272 pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial);
273 if (initial > iov->total_VFs ||
274 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total_VFs)))
275 return -EIO;
276
277 if (nr_virtfn < 0 || nr_virtfn > iov->total_VFs ||
278 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
279 return -EINVAL;
280
281 nres = 0;
282 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
283 bars |= (1 << (i + PCI_IOV_RESOURCES));
284 res = &dev->resource[i + PCI_IOV_RESOURCES];
285 if (res->parent)
286 nres++;
287 }
288 if (nres != iov->nres) {
289 pci_err(dev, "not enough MMIO resources for SR-IOV\n");
290 return -ENOMEM;
291 }
292
293 bus = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
294 if (bus > dev->bus->busn_res.end) {
295 pci_err(dev, "can't enable %d VFs (bus %02x out of range of %pR)\n",
296 nr_virtfn, bus, &dev->bus->busn_res);
297 return -ENOMEM;
298 }
299
300 if (pci_enable_resources(dev, bars)) {
301 pci_err(dev, "SR-IOV: IOV BARS not allocated\n");
302 return -ENOMEM;
303 }
304
305 if (iov->link != dev->devfn) {
306 pdev = pci_get_slot(dev->bus, iov->link);
307 if (!pdev)
308 return -ENODEV;
309
310 if (!pdev->is_physfn) {
311 pci_dev_put(pdev);
312 return -ENOSYS;
313 }
314
315 rc = sysfs_create_link(&dev->dev.kobj,
316 &pdev->dev.kobj, "dep_link");
317 pci_dev_put(pdev);
318 if (rc)
319 return rc;
320 }
321
322 iov->initial_VFs = initial;
323 if (nr_virtfn < initial)
324 initial = nr_virtfn;
325
326 rc = pcibios_sriov_enable(dev, initial);
327 if (rc) {
328 pci_err(dev, "failure %d from pcibios_sriov_enable()\n", rc);
329 goto err_pcibios;
330 }
331
332 pci_iov_set_numvfs(dev, nr_virtfn);
333 iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
334 pci_cfg_access_lock(dev);
335 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
336 msleep(100);
337 pci_cfg_access_unlock(dev);
338
339 for (i = 0; i < initial; i++) {
340 rc = pci_iov_add_virtfn(dev, i);
341 if (rc)
342 goto failed;
343 }
344
345 kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE);
346 iov->num_VFs = nr_virtfn;
347
348 return 0;
349
350failed:
351 while (i--)
352 pci_iov_remove_virtfn(dev, i);
353
354err_pcibios:
355 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
356 pci_cfg_access_lock(dev);
357 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
358 ssleep(1);
359 pci_cfg_access_unlock(dev);
360
361 pcibios_sriov_disable(dev);
362
363 if (iov->link != dev->devfn)
364 sysfs_remove_link(&dev->dev.kobj, "dep_link");
365
366 pci_iov_set_numvfs(dev, 0);
367 return rc;
368}
369
370static void sriov_disable(struct pci_dev *dev)
371{
372 int i;
373 struct pci_sriov *iov = dev->sriov;
374
375 if (!iov->num_VFs)
376 return;
377
378 for (i = 0; i < iov->num_VFs; i++)
379 pci_iov_remove_virtfn(dev, i);
380
381 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
382 pci_cfg_access_lock(dev);
383 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
384 ssleep(1);
385 pci_cfg_access_unlock(dev);
386
387 pcibios_sriov_disable(dev);
388
389 if (iov->link != dev->devfn)
390 sysfs_remove_link(&dev->dev.kobj, "dep_link");
391
392 iov->num_VFs = 0;
393 pci_iov_set_numvfs(dev, 0);
394}
395
396static int sriov_init(struct pci_dev *dev, int pos)
397{
398 int i, bar64;
399 int rc;
400 int nres;
401 u32 pgsz;
402 u16 ctrl, total;
403 struct pci_sriov *iov;
404 struct resource *res;
405 struct pci_dev *pdev;
406
407 pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl);
408 if (ctrl & PCI_SRIOV_CTRL_VFE) {
409 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0);
410 ssleep(1);
411 }
412
413 ctrl = 0;
414 list_for_each_entry(pdev, &dev->bus->devices, bus_list)
415 if (pdev->is_physfn)
416 goto found;
417
418 pdev = NULL;
419 if (pci_ari_enabled(dev->bus))
420 ctrl |= PCI_SRIOV_CTRL_ARI;
421
422found:
423 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl);
424
425 pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total);
426 if (!total)
427 return 0;
428
429 pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz);
430 i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0;
431 pgsz &= ~((1 << i) - 1);
432 if (!pgsz)
433 return -EIO;
434
435 pgsz &= ~(pgsz - 1);
436 pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz);
437
438 iov = kzalloc(sizeof(*iov), GFP_KERNEL);
439 if (!iov)
440 return -ENOMEM;
441
442 nres = 0;
443 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
444 res = &dev->resource[i + PCI_IOV_RESOURCES];
445 /*
446 * If it is already FIXED, don't change it, something
447 * (perhaps EA or header fixups) wants it this way.
448 */
449 if (res->flags & IORESOURCE_PCI_FIXED)
450 bar64 = (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
451 else
452 bar64 = __pci_read_base(dev, pci_bar_unknown, res,
453 pos + PCI_SRIOV_BAR + i * 4);
454 if (!res->flags)
455 continue;
456 if (resource_size(res) & (PAGE_SIZE - 1)) {
457 rc = -EIO;
458 goto failed;
459 }
460 iov->barsz[i] = resource_size(res);
461 res->end = res->start + resource_size(res) * total - 1;
462 pci_info(dev, "VF(n) BAR%d space: %pR (contains BAR%d for %d VFs)\n",
463 i, res, i, total);
464 i += bar64;
465 nres++;
466 }
467
468 iov->pos = pos;
469 iov->nres = nres;
470 iov->ctrl = ctrl;
471 iov->total_VFs = total;
472 pci_read_config_word(dev, pos + PCI_SRIOV_VF_DID, &iov->vf_device);
473 iov->pgsz = pgsz;
474 iov->self = dev;
475 iov->drivers_autoprobe = true;
476 pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap);
477 pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link);
478 if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END)
479 iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link);
480
481 if (pdev)
482 iov->dev = pci_dev_get(pdev);
483 else
484 iov->dev = dev;
485
486 dev->sriov = iov;
487 dev->is_physfn = 1;
488 rc = compute_max_vf_buses(dev);
489 if (rc)
490 goto fail_max_buses;
491
492 return 0;
493
494fail_max_buses:
495 dev->sriov = NULL;
496 dev->is_physfn = 0;
497failed:
498 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
499 res = &dev->resource[i + PCI_IOV_RESOURCES];
500 res->flags = 0;
501 }
502
503 kfree(iov);
504 return rc;
505}
506
507static void sriov_release(struct pci_dev *dev)
508{
509 BUG_ON(dev->sriov->num_VFs);
510
511 if (dev != dev->sriov->dev)
512 pci_dev_put(dev->sriov->dev);
513
514 kfree(dev->sriov);
515 dev->sriov = NULL;
516}
517
518static void sriov_restore_state(struct pci_dev *dev)
519{
520 int i;
521 u16 ctrl;
522 struct pci_sriov *iov = dev->sriov;
523
524 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl);
525 if (ctrl & PCI_SRIOV_CTRL_VFE)
526 return;
527
528 /*
529 * Restore PCI_SRIOV_CTRL_ARI before pci_iov_set_numvfs() because
530 * it reads offset & stride, which depend on PCI_SRIOV_CTRL_ARI.
531 */
532 ctrl &= ~PCI_SRIOV_CTRL_ARI;
533 ctrl |= iov->ctrl & PCI_SRIOV_CTRL_ARI;
534 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, ctrl);
535
536 for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++)
537 pci_update_resource(dev, i);
538
539 pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
540 pci_iov_set_numvfs(dev, iov->num_VFs);
541 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
542 if (iov->ctrl & PCI_SRIOV_CTRL_VFE)
543 msleep(100);
544}
545
546/**
547 * pci_iov_init - initialize the IOV capability
548 * @dev: the PCI device
549 *
550 * Returns 0 on success, or negative on failure.
551 */
552int pci_iov_init(struct pci_dev *dev)
553{
554 int pos;
555
556 if (!pci_is_pcie(dev))
557 return -ENODEV;
558
559 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV);
560 if (pos)
561 return sriov_init(dev, pos);
562
563 return -ENODEV;
564}
565
566/**
567 * pci_iov_release - release resources used by the IOV capability
568 * @dev: the PCI device
569 */
570void pci_iov_release(struct pci_dev *dev)
571{
572 if (dev->is_physfn)
573 sriov_release(dev);
574}
575
576/**
577 * pci_iov_update_resource - update a VF BAR
578 * @dev: the PCI device
579 * @resno: the resource number
580 *
581 * Update a VF BAR in the SR-IOV capability of a PF.
582 */
583void pci_iov_update_resource(struct pci_dev *dev, int resno)
584{
585 struct pci_sriov *iov = dev->is_physfn ? dev->sriov : NULL;
586 struct resource *res = dev->resource + resno;
587 int vf_bar = resno - PCI_IOV_RESOURCES;
588 struct pci_bus_region region;
589 u16 cmd;
590 u32 new;
591 int reg;
592
593 /*
594 * The generic pci_restore_bars() path calls this for all devices,
595 * including VFs and non-SR-IOV devices. If this is not a PF, we
596 * have nothing to do.
597 */
598 if (!iov)
599 return;
600
601 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &cmd);
602 if ((cmd & PCI_SRIOV_CTRL_VFE) && (cmd & PCI_SRIOV_CTRL_MSE)) {
603 dev_WARN(&dev->dev, "can't update enabled VF BAR%d %pR\n",
604 vf_bar, res);
605 return;
606 }
607
608 /*
609 * Ignore unimplemented BARs, unused resource slots for 64-bit
610 * BARs, and non-movable resources, e.g., those described via
611 * Enhanced Allocation.
612 */
613 if (!res->flags)
614 return;
615
616 if (res->flags & IORESOURCE_UNSET)
617 return;
618
619 if (res->flags & IORESOURCE_PCI_FIXED)
620 return;
621
622 pcibios_resource_to_bus(dev->bus, ®ion, res);
623 new = region.start;
624 new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK;
625
626 reg = iov->pos + PCI_SRIOV_BAR + 4 * vf_bar;
627 pci_write_config_dword(dev, reg, new);
628 if (res->flags & IORESOURCE_MEM_64) {
629 new = region.start >> 16 >> 16;
630 pci_write_config_dword(dev, reg + 4, new);
631 }
632}
633
634resource_size_t __weak pcibios_iov_resource_alignment(struct pci_dev *dev,
635 int resno)
636{
637 return pci_iov_resource_size(dev, resno);
638}
639
640/**
641 * pci_sriov_resource_alignment - get resource alignment for VF BAR
642 * @dev: the PCI device
643 * @resno: the resource number
644 *
645 * Returns the alignment of the VF BAR found in the SR-IOV capability.
646 * This is not the same as the resource size which is defined as
647 * the VF BAR size multiplied by the number of VFs. The alignment
648 * is just the VF BAR size.
649 */
650resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno)
651{
652 return pcibios_iov_resource_alignment(dev, resno);
653}
654
655/**
656 * pci_restore_iov_state - restore the state of the IOV capability
657 * @dev: the PCI device
658 */
659void pci_restore_iov_state(struct pci_dev *dev)
660{
661 if (dev->is_physfn)
662 sriov_restore_state(dev);
663}
664
665/**
666 * pci_vf_drivers_autoprobe - set PF property drivers_autoprobe for VFs
667 * @dev: the PCI device
668 * @auto_probe: set VF drivers auto probe flag
669 */
670void pci_vf_drivers_autoprobe(struct pci_dev *dev, bool auto_probe)
671{
672 if (dev->is_physfn)
673 dev->sriov->drivers_autoprobe = auto_probe;
674}
675
676/**
677 * pci_iov_bus_range - find bus range used by Virtual Function
678 * @bus: the PCI bus
679 *
680 * Returns max number of buses (exclude current one) used by Virtual
681 * Functions.
682 */
683int pci_iov_bus_range(struct pci_bus *bus)
684{
685 int max = 0;
686 struct pci_dev *dev;
687
688 list_for_each_entry(dev, &bus->devices, bus_list) {
689 if (!dev->is_physfn)
690 continue;
691 if (dev->sriov->max_VF_buses > max)
692 max = dev->sriov->max_VF_buses;
693 }
694
695 return max ? max - bus->number : 0;
696}
697
698/**
699 * pci_enable_sriov - enable the SR-IOV capability
700 * @dev: the PCI device
701 * @nr_virtfn: number of virtual functions to enable
702 *
703 * Returns 0 on success, or negative on failure.
704 */
705int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
706{
707 might_sleep();
708
709 if (!dev->is_physfn)
710 return -ENOSYS;
711
712 return sriov_enable(dev, nr_virtfn);
713}
714EXPORT_SYMBOL_GPL(pci_enable_sriov);
715
716/**
717 * pci_disable_sriov - disable the SR-IOV capability
718 * @dev: the PCI device
719 */
720void pci_disable_sriov(struct pci_dev *dev)
721{
722 might_sleep();
723
724 if (!dev->is_physfn)
725 return;
726
727 sriov_disable(dev);
728}
729EXPORT_SYMBOL_GPL(pci_disable_sriov);
730
731/**
732 * pci_num_vf - return number of VFs associated with a PF device_release_driver
733 * @dev: the PCI device
734 *
735 * Returns number of VFs, or 0 if SR-IOV is not enabled.
736 */
737int pci_num_vf(struct pci_dev *dev)
738{
739 if (!dev->is_physfn)
740 return 0;
741
742 return dev->sriov->num_VFs;
743}
744EXPORT_SYMBOL_GPL(pci_num_vf);
745
746/**
747 * pci_vfs_assigned - returns number of VFs are assigned to a guest
748 * @dev: the PCI device
749 *
750 * Returns number of VFs belonging to this device that are assigned to a guest.
751 * If device is not a physical function returns 0.
752 */
753int pci_vfs_assigned(struct pci_dev *dev)
754{
755 struct pci_dev *vfdev;
756 unsigned int vfs_assigned = 0;
757 unsigned short dev_id;
758
759 /* only search if we are a PF */
760 if (!dev->is_physfn)
761 return 0;
762
763 /*
764 * determine the device ID for the VFs, the vendor ID will be the
765 * same as the PF so there is no need to check for that one
766 */
767 dev_id = dev->sriov->vf_device;
768
769 /* loop through all the VFs to see if we own any that are assigned */
770 vfdev = pci_get_device(dev->vendor, dev_id, NULL);
771 while (vfdev) {
772 /*
773 * It is considered assigned if it is a virtual function with
774 * our dev as the physical function and the assigned bit is set
775 */
776 if (vfdev->is_virtfn && (vfdev->physfn == dev) &&
777 pci_is_dev_assigned(vfdev))
778 vfs_assigned++;
779
780 vfdev = pci_get_device(dev->vendor, dev_id, vfdev);
781 }
782
783 return vfs_assigned;
784}
785EXPORT_SYMBOL_GPL(pci_vfs_assigned);
786
787/**
788 * pci_sriov_set_totalvfs -- reduce the TotalVFs available
789 * @dev: the PCI PF device
790 * @numvfs: number that should be used for TotalVFs supported
791 *
792 * Should be called from PF driver's probe routine with
793 * device's mutex held.
794 *
795 * Returns 0 if PF is an SRIOV-capable device and
796 * value of numvfs valid. If not a PF return -ENOSYS;
797 * if numvfs is invalid return -EINVAL;
798 * if VFs already enabled, return -EBUSY.
799 */
800int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs)
801{
802 if (!dev->is_physfn)
803 return -ENOSYS;
804 if (numvfs > dev->sriov->total_VFs)
805 return -EINVAL;
806
807 /* Shouldn't change if VFs already enabled */
808 if (dev->sriov->ctrl & PCI_SRIOV_CTRL_VFE)
809 return -EBUSY;
810 else
811 dev->sriov->driver_max_VFs = numvfs;
812
813 return 0;
814}
815EXPORT_SYMBOL_GPL(pci_sriov_set_totalvfs);
816
817/**
818 * pci_sriov_get_totalvfs -- get total VFs supported on this device
819 * @dev: the PCI PF device
820 *
821 * For a PCIe device with SRIOV support, return the PCIe
822 * SRIOV capability value of TotalVFs or the value of driver_max_VFs
823 * if the driver reduced it. Otherwise 0.
824 */
825int pci_sriov_get_totalvfs(struct pci_dev *dev)
826{
827 if (!dev->is_physfn)
828 return 0;
829
830 if (dev->sriov->driver_max_VFs)
831 return dev->sriov->driver_max_VFs;
832
833 return dev->sriov->total_VFs;
834}
835EXPORT_SYMBOL_GPL(pci_sriov_get_totalvfs);