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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * PCI Express I/O Virtualization (IOV) support
4 * Single Root IOV 1.0
5 * Address Translation Service 1.0
6 *
7 * Copyright (C) 2009 Intel Corporation, Yu Zhao <yu.zhao@intel.com>
8 */
9
10#include <linux/pci.h>
11#include <linux/slab.h>
12#include <linux/mutex.h>
13#include <linux/export.h>
14#include <linux/string.h>
15#include <linux/delay.h>
16#include "pci.h"
17
18#define VIRTFN_ID_LEN 16
19
20int pci_iov_virtfn_bus(struct pci_dev *dev, int vf_id)
21{
22 if (!dev->is_physfn)
23 return -EINVAL;
24 return dev->bus->number + ((dev->devfn + dev->sriov->offset +
25 dev->sriov->stride * vf_id) >> 8);
26}
27
28int pci_iov_virtfn_devfn(struct pci_dev *dev, int vf_id)
29{
30 if (!dev->is_physfn)
31 return -EINVAL;
32 return (dev->devfn + dev->sriov->offset +
33 dev->sriov->stride * vf_id) & 0xff;
34}
35
36/*
37 * Per SR-IOV spec sec 3.3.10 and 3.3.11, First VF Offset and VF Stride may
38 * change when NumVFs changes.
39 *
40 * Update iov->offset and iov->stride when NumVFs is written.
41 */
42static inline void pci_iov_set_numvfs(struct pci_dev *dev, int nr_virtfn)
43{
44 struct pci_sriov *iov = dev->sriov;
45
46 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn);
47 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &iov->offset);
48 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &iov->stride);
49}
50
51/*
52 * The PF consumes one bus number. NumVFs, First VF Offset, and VF Stride
53 * determine how many additional bus numbers will be consumed by VFs.
54 *
55 * Iterate over all valid NumVFs, validate offset and stride, and calculate
56 * the maximum number of bus numbers that could ever be required.
57 */
58static int compute_max_vf_buses(struct pci_dev *dev)
59{
60 struct pci_sriov *iov = dev->sriov;
61 int nr_virtfn, busnr, rc = 0;
62
63 for (nr_virtfn = iov->total_VFs; nr_virtfn; nr_virtfn--) {
64 pci_iov_set_numvfs(dev, nr_virtfn);
65 if (!iov->offset || (nr_virtfn > 1 && !iov->stride)) {
66 rc = -EIO;
67 goto out;
68 }
69
70 busnr = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
71 if (busnr > iov->max_VF_buses)
72 iov->max_VF_buses = busnr;
73 }
74
75out:
76 pci_iov_set_numvfs(dev, 0);
77 return rc;
78}
79
80static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr)
81{
82 struct pci_bus *child;
83
84 if (bus->number == busnr)
85 return bus;
86
87 child = pci_find_bus(pci_domain_nr(bus), busnr);
88 if (child)
89 return child;
90
91 child = pci_add_new_bus(bus, NULL, busnr);
92 if (!child)
93 return NULL;
94
95 pci_bus_insert_busn_res(child, busnr, busnr);
96
97 return child;
98}
99
100static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus)
101{
102 if (physbus != virtbus && list_empty(&virtbus->devices))
103 pci_remove_bus(virtbus);
104}
105
106resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)
107{
108 if (!dev->is_physfn)
109 return 0;
110
111 return dev->sriov->barsz[resno - PCI_IOV_RESOURCES];
112}
113
114static void pci_read_vf_config_common(struct pci_dev *virtfn)
115{
116 struct pci_dev *physfn = virtfn->physfn;
117
118 /*
119 * Some config registers are the same across all associated VFs.
120 * Read them once from VF0 so we can skip reading them from the
121 * other VFs.
122 *
123 * PCIe r4.0, sec 9.3.4.1, technically doesn't require all VFs to
124 * have the same Revision ID and Subsystem ID, but we assume they
125 * do.
126 */
127 pci_read_config_dword(virtfn, PCI_CLASS_REVISION,
128 &physfn->sriov->class);
129 pci_read_config_byte(virtfn, PCI_HEADER_TYPE,
130 &physfn->sriov->hdr_type);
131 pci_read_config_word(virtfn, PCI_SUBSYSTEM_VENDOR_ID,
132 &physfn->sriov->subsystem_vendor);
133 pci_read_config_word(virtfn, PCI_SUBSYSTEM_ID,
134 &physfn->sriov->subsystem_device);
135}
136
137int pci_iov_add_virtfn(struct pci_dev *dev, int id)
138{
139 int i;
140 int rc = -ENOMEM;
141 u64 size;
142 char buf[VIRTFN_ID_LEN];
143 struct pci_dev *virtfn;
144 struct resource *res;
145 struct pci_sriov *iov = dev->sriov;
146 struct pci_bus *bus;
147
148 bus = virtfn_add_bus(dev->bus, pci_iov_virtfn_bus(dev, id));
149 if (!bus)
150 goto failed;
151
152 virtfn = pci_alloc_dev(bus);
153 if (!virtfn)
154 goto failed0;
155
156 virtfn->devfn = pci_iov_virtfn_devfn(dev, id);
157 virtfn->vendor = dev->vendor;
158 virtfn->device = iov->vf_device;
159 virtfn->is_virtfn = 1;
160 virtfn->physfn = pci_dev_get(dev);
161
162 if (id == 0)
163 pci_read_vf_config_common(virtfn);
164
165 rc = pci_setup_device(virtfn);
166 if (rc)
167 goto failed1;
168
169 virtfn->dev.parent = dev->dev.parent;
170 virtfn->multifunction = 0;
171
172 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
173 res = &dev->resource[i + PCI_IOV_RESOURCES];
174 if (!res->parent)
175 continue;
176 virtfn->resource[i].name = pci_name(virtfn);
177 virtfn->resource[i].flags = res->flags;
178 size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);
179 virtfn->resource[i].start = res->start + size * id;
180 virtfn->resource[i].end = virtfn->resource[i].start + size - 1;
181 rc = request_resource(res, &virtfn->resource[i]);
182 BUG_ON(rc);
183 }
184
185 pci_device_add(virtfn, virtfn->bus);
186
187 sprintf(buf, "virtfn%u", id);
188 rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
189 if (rc)
190 goto failed2;
191 rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");
192 if (rc)
193 goto failed3;
194
195 kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);
196
197 pci_bus_add_device(virtfn);
198
199 return 0;
200
201failed3:
202 sysfs_remove_link(&dev->dev.kobj, buf);
203failed2:
204 pci_stop_and_remove_bus_device(virtfn);
205failed1:
206 pci_dev_put(dev);
207failed0:
208 virtfn_remove_bus(dev->bus, bus);
209failed:
210
211 return rc;
212}
213
214void pci_iov_remove_virtfn(struct pci_dev *dev, int id)
215{
216 char buf[VIRTFN_ID_LEN];
217 struct pci_dev *virtfn;
218
219 virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus),
220 pci_iov_virtfn_bus(dev, id),
221 pci_iov_virtfn_devfn(dev, id));
222 if (!virtfn)
223 return;
224
225 sprintf(buf, "virtfn%u", id);
226 sysfs_remove_link(&dev->dev.kobj, buf);
227 /*
228 * pci_stop_dev() could have been called for this virtfn already,
229 * so the directory for the virtfn may have been removed before.
230 * Double check to avoid spurious sysfs warnings.
231 */
232 if (virtfn->dev.kobj.sd)
233 sysfs_remove_link(&virtfn->dev.kobj, "physfn");
234
235 pci_stop_and_remove_bus_device(virtfn);
236 virtfn_remove_bus(dev->bus, virtfn->bus);
237
238 /* balance pci_get_domain_bus_and_slot() */
239 pci_dev_put(virtfn);
240 pci_dev_put(dev);
241}
242
243static ssize_t sriov_totalvfs_show(struct device *dev,
244 struct device_attribute *attr,
245 char *buf)
246{
247 struct pci_dev *pdev = to_pci_dev(dev);
248
249 return sprintf(buf, "%u\n", pci_sriov_get_totalvfs(pdev));
250}
251
252static ssize_t sriov_numvfs_show(struct device *dev,
253 struct device_attribute *attr,
254 char *buf)
255{
256 struct pci_dev *pdev = to_pci_dev(dev);
257
258 return sprintf(buf, "%u\n", pdev->sriov->num_VFs);
259}
260
261/*
262 * num_vfs > 0; number of VFs to enable
263 * num_vfs = 0; disable all VFs
264 *
265 * Note: SRIOV spec does not allow partial VF
266 * disable, so it's all or none.
267 */
268static ssize_t sriov_numvfs_store(struct device *dev,
269 struct device_attribute *attr,
270 const char *buf, size_t count)
271{
272 struct pci_dev *pdev = to_pci_dev(dev);
273 int ret;
274 u16 num_vfs;
275
276 ret = kstrtou16(buf, 0, &num_vfs);
277 if (ret < 0)
278 return ret;
279
280 if (num_vfs > pci_sriov_get_totalvfs(pdev))
281 return -ERANGE;
282
283 device_lock(&pdev->dev);
284
285 if (num_vfs == pdev->sriov->num_VFs)
286 goto exit;
287
288 /* is PF driver loaded w/callback */
289 if (!pdev->driver || !pdev->driver->sriov_configure) {
290 pci_info(pdev, "Driver does not support SRIOV configuration via sysfs\n");
291 ret = -ENOENT;
292 goto exit;
293 }
294
295 if (num_vfs == 0) {
296 /* disable VFs */
297 ret = pdev->driver->sriov_configure(pdev, 0);
298 goto exit;
299 }
300
301 /* enable VFs */
302 if (pdev->sriov->num_VFs) {
303 pci_warn(pdev, "%d VFs already enabled. Disable before enabling %d VFs\n",
304 pdev->sriov->num_VFs, num_vfs);
305 ret = -EBUSY;
306 goto exit;
307 }
308
309 ret = pdev->driver->sriov_configure(pdev, num_vfs);
310 if (ret < 0)
311 goto exit;
312
313 if (ret != num_vfs)
314 pci_warn(pdev, "%d VFs requested; only %d enabled\n",
315 num_vfs, ret);
316
317exit:
318 device_unlock(&pdev->dev);
319
320 if (ret < 0)
321 return ret;
322
323 return count;
324}
325
326static ssize_t sriov_offset_show(struct device *dev,
327 struct device_attribute *attr,
328 char *buf)
329{
330 struct pci_dev *pdev = to_pci_dev(dev);
331
332 return sprintf(buf, "%u\n", pdev->sriov->offset);
333}
334
335static ssize_t sriov_stride_show(struct device *dev,
336 struct device_attribute *attr,
337 char *buf)
338{
339 struct pci_dev *pdev = to_pci_dev(dev);
340
341 return sprintf(buf, "%u\n", pdev->sriov->stride);
342}
343
344static ssize_t sriov_vf_device_show(struct device *dev,
345 struct device_attribute *attr,
346 char *buf)
347{
348 struct pci_dev *pdev = to_pci_dev(dev);
349
350 return sprintf(buf, "%x\n", pdev->sriov->vf_device);
351}
352
353static ssize_t sriov_drivers_autoprobe_show(struct device *dev,
354 struct device_attribute *attr,
355 char *buf)
356{
357 struct pci_dev *pdev = to_pci_dev(dev);
358
359 return sprintf(buf, "%u\n", pdev->sriov->drivers_autoprobe);
360}
361
362static ssize_t sriov_drivers_autoprobe_store(struct device *dev,
363 struct device_attribute *attr,
364 const char *buf, size_t count)
365{
366 struct pci_dev *pdev = to_pci_dev(dev);
367 bool drivers_autoprobe;
368
369 if (kstrtobool(buf, &drivers_autoprobe) < 0)
370 return -EINVAL;
371
372 pdev->sriov->drivers_autoprobe = drivers_autoprobe;
373
374 return count;
375}
376
377static DEVICE_ATTR_RO(sriov_totalvfs);
378static DEVICE_ATTR_RW(sriov_numvfs);
379static DEVICE_ATTR_RO(sriov_offset);
380static DEVICE_ATTR_RO(sriov_stride);
381static DEVICE_ATTR_RO(sriov_vf_device);
382static DEVICE_ATTR_RW(sriov_drivers_autoprobe);
383
384static struct attribute *sriov_dev_attrs[] = {
385 &dev_attr_sriov_totalvfs.attr,
386 &dev_attr_sriov_numvfs.attr,
387 &dev_attr_sriov_offset.attr,
388 &dev_attr_sriov_stride.attr,
389 &dev_attr_sriov_vf_device.attr,
390 &dev_attr_sriov_drivers_autoprobe.attr,
391 NULL,
392};
393
394static umode_t sriov_attrs_are_visible(struct kobject *kobj,
395 struct attribute *a, int n)
396{
397 struct device *dev = kobj_to_dev(kobj);
398
399 if (!dev_is_pf(dev))
400 return 0;
401
402 return a->mode;
403}
404
405const struct attribute_group sriov_dev_attr_group = {
406 .attrs = sriov_dev_attrs,
407 .is_visible = sriov_attrs_are_visible,
408};
409
410int __weak pcibios_sriov_enable(struct pci_dev *pdev, u16 num_vfs)
411{
412 return 0;
413}
414
415int __weak pcibios_sriov_disable(struct pci_dev *pdev)
416{
417 return 0;
418}
419
420static int sriov_add_vfs(struct pci_dev *dev, u16 num_vfs)
421{
422 unsigned int i;
423 int rc;
424
425 if (dev->no_vf_scan)
426 return 0;
427
428 for (i = 0; i < num_vfs; i++) {
429 rc = pci_iov_add_virtfn(dev, i);
430 if (rc)
431 goto failed;
432 }
433 return 0;
434failed:
435 while (i--)
436 pci_iov_remove_virtfn(dev, i);
437
438 return rc;
439}
440
441static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
442{
443 int rc;
444 int i;
445 int nres;
446 u16 initial;
447 struct resource *res;
448 struct pci_dev *pdev;
449 struct pci_sriov *iov = dev->sriov;
450 int bars = 0;
451 int bus;
452
453 if (!nr_virtfn)
454 return 0;
455
456 if (iov->num_VFs)
457 return -EINVAL;
458
459 pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial);
460 if (initial > iov->total_VFs ||
461 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total_VFs)))
462 return -EIO;
463
464 if (nr_virtfn < 0 || nr_virtfn > iov->total_VFs ||
465 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
466 return -EINVAL;
467
468 nres = 0;
469 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
470 bars |= (1 << (i + PCI_IOV_RESOURCES));
471 res = &dev->resource[i + PCI_IOV_RESOURCES];
472 if (res->parent)
473 nres++;
474 }
475 if (nres != iov->nres) {
476 pci_err(dev, "not enough MMIO resources for SR-IOV\n");
477 return -ENOMEM;
478 }
479
480 bus = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
481 if (bus > dev->bus->busn_res.end) {
482 pci_err(dev, "can't enable %d VFs (bus %02x out of range of %pR)\n",
483 nr_virtfn, bus, &dev->bus->busn_res);
484 return -ENOMEM;
485 }
486
487 if (pci_enable_resources(dev, bars)) {
488 pci_err(dev, "SR-IOV: IOV BARS not allocated\n");
489 return -ENOMEM;
490 }
491
492 if (iov->link != dev->devfn) {
493 pdev = pci_get_slot(dev->bus, iov->link);
494 if (!pdev)
495 return -ENODEV;
496
497 if (!pdev->is_physfn) {
498 pci_dev_put(pdev);
499 return -ENOSYS;
500 }
501
502 rc = sysfs_create_link(&dev->dev.kobj,
503 &pdev->dev.kobj, "dep_link");
504 pci_dev_put(pdev);
505 if (rc)
506 return rc;
507 }
508
509 iov->initial_VFs = initial;
510 if (nr_virtfn < initial)
511 initial = nr_virtfn;
512
513 rc = pcibios_sriov_enable(dev, initial);
514 if (rc) {
515 pci_err(dev, "failure %d from pcibios_sriov_enable()\n", rc);
516 goto err_pcibios;
517 }
518
519 pci_iov_set_numvfs(dev, nr_virtfn);
520 iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
521 pci_cfg_access_lock(dev);
522 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
523 msleep(100);
524 pci_cfg_access_unlock(dev);
525
526 rc = sriov_add_vfs(dev, initial);
527 if (rc)
528 goto err_pcibios;
529
530 kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE);
531 iov->num_VFs = nr_virtfn;
532
533 return 0;
534
535err_pcibios:
536 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
537 pci_cfg_access_lock(dev);
538 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
539 ssleep(1);
540 pci_cfg_access_unlock(dev);
541
542 pcibios_sriov_disable(dev);
543
544 if (iov->link != dev->devfn)
545 sysfs_remove_link(&dev->dev.kobj, "dep_link");
546
547 pci_iov_set_numvfs(dev, 0);
548 return rc;
549}
550
551static void sriov_del_vfs(struct pci_dev *dev)
552{
553 struct pci_sriov *iov = dev->sriov;
554 int i;
555
556 if (dev->no_vf_scan)
557 return;
558
559 for (i = 0; i < iov->num_VFs; i++)
560 pci_iov_remove_virtfn(dev, i);
561}
562
563static void sriov_disable(struct pci_dev *dev)
564{
565 struct pci_sriov *iov = dev->sriov;
566
567 if (!iov->num_VFs)
568 return;
569
570 sriov_del_vfs(dev);
571 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
572 pci_cfg_access_lock(dev);
573 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
574 ssleep(1);
575 pci_cfg_access_unlock(dev);
576
577 pcibios_sriov_disable(dev);
578
579 if (iov->link != dev->devfn)
580 sysfs_remove_link(&dev->dev.kobj, "dep_link");
581
582 iov->num_VFs = 0;
583 pci_iov_set_numvfs(dev, 0);
584}
585
586static int sriov_init(struct pci_dev *dev, int pos)
587{
588 int i, bar64;
589 int rc;
590 int nres;
591 u32 pgsz;
592 u16 ctrl, total;
593 struct pci_sriov *iov;
594 struct resource *res;
595 struct pci_dev *pdev;
596
597 pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl);
598 if (ctrl & PCI_SRIOV_CTRL_VFE) {
599 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0);
600 ssleep(1);
601 }
602
603 ctrl = 0;
604 list_for_each_entry(pdev, &dev->bus->devices, bus_list)
605 if (pdev->is_physfn)
606 goto found;
607
608 pdev = NULL;
609 if (pci_ari_enabled(dev->bus))
610 ctrl |= PCI_SRIOV_CTRL_ARI;
611
612found:
613 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl);
614
615 pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total);
616 if (!total)
617 return 0;
618
619 pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz);
620 i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0;
621 pgsz &= ~((1 << i) - 1);
622 if (!pgsz)
623 return -EIO;
624
625 pgsz &= ~(pgsz - 1);
626 pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz);
627
628 iov = kzalloc(sizeof(*iov), GFP_KERNEL);
629 if (!iov)
630 return -ENOMEM;
631
632 nres = 0;
633 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
634 res = &dev->resource[i + PCI_IOV_RESOURCES];
635 /*
636 * If it is already FIXED, don't change it, something
637 * (perhaps EA or header fixups) wants it this way.
638 */
639 if (res->flags & IORESOURCE_PCI_FIXED)
640 bar64 = (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
641 else
642 bar64 = __pci_read_base(dev, pci_bar_unknown, res,
643 pos + PCI_SRIOV_BAR + i * 4);
644 if (!res->flags)
645 continue;
646 if (resource_size(res) & (PAGE_SIZE - 1)) {
647 rc = -EIO;
648 goto failed;
649 }
650 iov->barsz[i] = resource_size(res);
651 res->end = res->start + resource_size(res) * total - 1;
652 pci_info(dev, "VF(n) BAR%d space: %pR (contains BAR%d for %d VFs)\n",
653 i, res, i, total);
654 i += bar64;
655 nres++;
656 }
657
658 iov->pos = pos;
659 iov->nres = nres;
660 iov->ctrl = ctrl;
661 iov->total_VFs = total;
662 iov->driver_max_VFs = total;
663 pci_read_config_word(dev, pos + PCI_SRIOV_VF_DID, &iov->vf_device);
664 iov->pgsz = pgsz;
665 iov->self = dev;
666 iov->drivers_autoprobe = true;
667 pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap);
668 pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link);
669 if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END)
670 iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link);
671
672 if (pdev)
673 iov->dev = pci_dev_get(pdev);
674 else
675 iov->dev = dev;
676
677 dev->sriov = iov;
678 dev->is_physfn = 1;
679 rc = compute_max_vf_buses(dev);
680 if (rc)
681 goto fail_max_buses;
682
683 return 0;
684
685fail_max_buses:
686 dev->sriov = NULL;
687 dev->is_physfn = 0;
688failed:
689 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
690 res = &dev->resource[i + PCI_IOV_RESOURCES];
691 res->flags = 0;
692 }
693
694 kfree(iov);
695 return rc;
696}
697
698static void sriov_release(struct pci_dev *dev)
699{
700 BUG_ON(dev->sriov->num_VFs);
701
702 if (dev != dev->sriov->dev)
703 pci_dev_put(dev->sriov->dev);
704
705 kfree(dev->sriov);
706 dev->sriov = NULL;
707}
708
709static void sriov_restore_state(struct pci_dev *dev)
710{
711 int i;
712 u16 ctrl;
713 struct pci_sriov *iov = dev->sriov;
714
715 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl);
716 if (ctrl & PCI_SRIOV_CTRL_VFE)
717 return;
718
719 /*
720 * Restore PCI_SRIOV_CTRL_ARI before pci_iov_set_numvfs() because
721 * it reads offset & stride, which depend on PCI_SRIOV_CTRL_ARI.
722 */
723 ctrl &= ~PCI_SRIOV_CTRL_ARI;
724 ctrl |= iov->ctrl & PCI_SRIOV_CTRL_ARI;
725 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, ctrl);
726
727 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++)
728 pci_update_resource(dev, i + PCI_IOV_RESOURCES);
729
730 pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
731 pci_iov_set_numvfs(dev, iov->num_VFs);
732 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
733 if (iov->ctrl & PCI_SRIOV_CTRL_VFE)
734 msleep(100);
735}
736
737/**
738 * pci_iov_init - initialize the IOV capability
739 * @dev: the PCI device
740 *
741 * Returns 0 on success, or negative on failure.
742 */
743int pci_iov_init(struct pci_dev *dev)
744{
745 int pos;
746
747 if (!pci_is_pcie(dev))
748 return -ENODEV;
749
750 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV);
751 if (pos)
752 return sriov_init(dev, pos);
753
754 return -ENODEV;
755}
756
757/**
758 * pci_iov_release - release resources used by the IOV capability
759 * @dev: the PCI device
760 */
761void pci_iov_release(struct pci_dev *dev)
762{
763 if (dev->is_physfn)
764 sriov_release(dev);
765}
766
767/**
768 * pci_iov_remove - clean up SR-IOV state after PF driver is detached
769 * @dev: the PCI device
770 */
771void pci_iov_remove(struct pci_dev *dev)
772{
773 struct pci_sriov *iov = dev->sriov;
774
775 if (!dev->is_physfn)
776 return;
777
778 iov->driver_max_VFs = iov->total_VFs;
779 if (iov->num_VFs)
780 pci_warn(dev, "driver left SR-IOV enabled after remove\n");
781}
782
783/**
784 * pci_iov_update_resource - update a VF BAR
785 * @dev: the PCI device
786 * @resno: the resource number
787 *
788 * Update a VF BAR in the SR-IOV capability of a PF.
789 */
790void pci_iov_update_resource(struct pci_dev *dev, int resno)
791{
792 struct pci_sriov *iov = dev->is_physfn ? dev->sriov : NULL;
793 struct resource *res = dev->resource + resno;
794 int vf_bar = resno - PCI_IOV_RESOURCES;
795 struct pci_bus_region region;
796 u16 cmd;
797 u32 new;
798 int reg;
799
800 /*
801 * The generic pci_restore_bars() path calls this for all devices,
802 * including VFs and non-SR-IOV devices. If this is not a PF, we
803 * have nothing to do.
804 */
805 if (!iov)
806 return;
807
808 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &cmd);
809 if ((cmd & PCI_SRIOV_CTRL_VFE) && (cmd & PCI_SRIOV_CTRL_MSE)) {
810 dev_WARN(&dev->dev, "can't update enabled VF BAR%d %pR\n",
811 vf_bar, res);
812 return;
813 }
814
815 /*
816 * Ignore unimplemented BARs, unused resource slots for 64-bit
817 * BARs, and non-movable resources, e.g., those described via
818 * Enhanced Allocation.
819 */
820 if (!res->flags)
821 return;
822
823 if (res->flags & IORESOURCE_UNSET)
824 return;
825
826 if (res->flags & IORESOURCE_PCI_FIXED)
827 return;
828
829 pcibios_resource_to_bus(dev->bus, ®ion, res);
830 new = region.start;
831 new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK;
832
833 reg = iov->pos + PCI_SRIOV_BAR + 4 * vf_bar;
834 pci_write_config_dword(dev, reg, new);
835 if (res->flags & IORESOURCE_MEM_64) {
836 new = region.start >> 16 >> 16;
837 pci_write_config_dword(dev, reg + 4, new);
838 }
839}
840
841resource_size_t __weak pcibios_iov_resource_alignment(struct pci_dev *dev,
842 int resno)
843{
844 return pci_iov_resource_size(dev, resno);
845}
846
847/**
848 * pci_sriov_resource_alignment - get resource alignment for VF BAR
849 * @dev: the PCI device
850 * @resno: the resource number
851 *
852 * Returns the alignment of the VF BAR found in the SR-IOV capability.
853 * This is not the same as the resource size which is defined as
854 * the VF BAR size multiplied by the number of VFs. The alignment
855 * is just the VF BAR size.
856 */
857resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno)
858{
859 return pcibios_iov_resource_alignment(dev, resno);
860}
861
862/**
863 * pci_restore_iov_state - restore the state of the IOV capability
864 * @dev: the PCI device
865 */
866void pci_restore_iov_state(struct pci_dev *dev)
867{
868 if (dev->is_physfn)
869 sriov_restore_state(dev);
870}
871
872/**
873 * pci_vf_drivers_autoprobe - set PF property drivers_autoprobe for VFs
874 * @dev: the PCI device
875 * @auto_probe: set VF drivers auto probe flag
876 */
877void pci_vf_drivers_autoprobe(struct pci_dev *dev, bool auto_probe)
878{
879 if (dev->is_physfn)
880 dev->sriov->drivers_autoprobe = auto_probe;
881}
882
883/**
884 * pci_iov_bus_range - find bus range used by Virtual Function
885 * @bus: the PCI bus
886 *
887 * Returns max number of buses (exclude current one) used by Virtual
888 * Functions.
889 */
890int pci_iov_bus_range(struct pci_bus *bus)
891{
892 int max = 0;
893 struct pci_dev *dev;
894
895 list_for_each_entry(dev, &bus->devices, bus_list) {
896 if (!dev->is_physfn)
897 continue;
898 if (dev->sriov->max_VF_buses > max)
899 max = dev->sriov->max_VF_buses;
900 }
901
902 return max ? max - bus->number : 0;
903}
904
905/**
906 * pci_enable_sriov - enable the SR-IOV capability
907 * @dev: the PCI device
908 * @nr_virtfn: number of virtual functions to enable
909 *
910 * Returns 0 on success, or negative on failure.
911 */
912int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
913{
914 might_sleep();
915
916 if (!dev->is_physfn)
917 return -ENOSYS;
918
919 return sriov_enable(dev, nr_virtfn);
920}
921EXPORT_SYMBOL_GPL(pci_enable_sriov);
922
923/**
924 * pci_disable_sriov - disable the SR-IOV capability
925 * @dev: the PCI device
926 */
927void pci_disable_sriov(struct pci_dev *dev)
928{
929 might_sleep();
930
931 if (!dev->is_physfn)
932 return;
933
934 sriov_disable(dev);
935}
936EXPORT_SYMBOL_GPL(pci_disable_sriov);
937
938/**
939 * pci_num_vf - return number of VFs associated with a PF device_release_driver
940 * @dev: the PCI device
941 *
942 * Returns number of VFs, or 0 if SR-IOV is not enabled.
943 */
944int pci_num_vf(struct pci_dev *dev)
945{
946 if (!dev->is_physfn)
947 return 0;
948
949 return dev->sriov->num_VFs;
950}
951EXPORT_SYMBOL_GPL(pci_num_vf);
952
953/**
954 * pci_vfs_assigned - returns number of VFs are assigned to a guest
955 * @dev: the PCI device
956 *
957 * Returns number of VFs belonging to this device that are assigned to a guest.
958 * If device is not a physical function returns 0.
959 */
960int pci_vfs_assigned(struct pci_dev *dev)
961{
962 struct pci_dev *vfdev;
963 unsigned int vfs_assigned = 0;
964 unsigned short dev_id;
965
966 /* only search if we are a PF */
967 if (!dev->is_physfn)
968 return 0;
969
970 /*
971 * determine the device ID for the VFs, the vendor ID will be the
972 * same as the PF so there is no need to check for that one
973 */
974 dev_id = dev->sriov->vf_device;
975
976 /* loop through all the VFs to see if we own any that are assigned */
977 vfdev = pci_get_device(dev->vendor, dev_id, NULL);
978 while (vfdev) {
979 /*
980 * It is considered assigned if it is a virtual function with
981 * our dev as the physical function and the assigned bit is set
982 */
983 if (vfdev->is_virtfn && (vfdev->physfn == dev) &&
984 pci_is_dev_assigned(vfdev))
985 vfs_assigned++;
986
987 vfdev = pci_get_device(dev->vendor, dev_id, vfdev);
988 }
989
990 return vfs_assigned;
991}
992EXPORT_SYMBOL_GPL(pci_vfs_assigned);
993
994/**
995 * pci_sriov_set_totalvfs -- reduce the TotalVFs available
996 * @dev: the PCI PF device
997 * @numvfs: number that should be used for TotalVFs supported
998 *
999 * Should be called from PF driver's probe routine with
1000 * device's mutex held.
1001 *
1002 * Returns 0 if PF is an SRIOV-capable device and
1003 * value of numvfs valid. If not a PF return -ENOSYS;
1004 * if numvfs is invalid return -EINVAL;
1005 * if VFs already enabled, return -EBUSY.
1006 */
1007int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs)
1008{
1009 if (!dev->is_physfn)
1010 return -ENOSYS;
1011
1012 if (numvfs > dev->sriov->total_VFs)
1013 return -EINVAL;
1014
1015 /* Shouldn't change if VFs already enabled */
1016 if (dev->sriov->ctrl & PCI_SRIOV_CTRL_VFE)
1017 return -EBUSY;
1018
1019 dev->sriov->driver_max_VFs = numvfs;
1020 return 0;
1021}
1022EXPORT_SYMBOL_GPL(pci_sriov_set_totalvfs);
1023
1024/**
1025 * pci_sriov_get_totalvfs -- get total VFs supported on this device
1026 * @dev: the PCI PF device
1027 *
1028 * For a PCIe device with SRIOV support, return the PCIe
1029 * SRIOV capability value of TotalVFs or the value of driver_max_VFs
1030 * if the driver reduced it. Otherwise 0.
1031 */
1032int pci_sriov_get_totalvfs(struct pci_dev *dev)
1033{
1034 if (!dev->is_physfn)
1035 return 0;
1036
1037 return dev->sriov->driver_max_VFs;
1038}
1039EXPORT_SYMBOL_GPL(pci_sriov_get_totalvfs);
1040
1041/**
1042 * pci_sriov_configure_simple - helper to configure SR-IOV
1043 * @dev: the PCI device
1044 * @nr_virtfn: number of virtual functions to enable, 0 to disable
1045 *
1046 * Enable or disable SR-IOV for devices that don't require any PF setup
1047 * before enabling SR-IOV. Return value is negative on error, or number of
1048 * VFs allocated on success.
1049 */
1050int pci_sriov_configure_simple(struct pci_dev *dev, int nr_virtfn)
1051{
1052 int rc;
1053
1054 might_sleep();
1055
1056 if (!dev->is_physfn)
1057 return -ENODEV;
1058
1059 if (pci_vfs_assigned(dev)) {
1060 pci_warn(dev, "Cannot modify SR-IOV while VFs are assigned\n");
1061 return -EPERM;
1062 }
1063
1064 if (nr_virtfn == 0) {
1065 sriov_disable(dev);
1066 return 0;
1067 }
1068
1069 rc = sriov_enable(dev, nr_virtfn);
1070 if (rc < 0)
1071 return rc;
1072
1073 return nr_virtfn;
1074}
1075EXPORT_SYMBOL_GPL(pci_sriov_configure_simple);
1/*
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
22static inline u8 virtfn_bus(struct pci_dev *dev, int id)
23{
24 return dev->bus->number + ((dev->devfn + dev->sriov->offset +
25 dev->sriov->stride * id) >> 8);
26}
27
28static inline u8 virtfn_devfn(struct pci_dev *dev, int id)
29{
30 return (dev->devfn + dev->sriov->offset +
31 dev->sriov->stride * id) & 0xff;
32}
33
34static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr)
35{
36 struct pci_bus *child;
37
38 if (bus->number == busnr)
39 return bus;
40
41 child = pci_find_bus(pci_domain_nr(bus), busnr);
42 if (child)
43 return child;
44
45 child = pci_add_new_bus(bus, NULL, busnr);
46 if (!child)
47 return NULL;
48
49 pci_bus_insert_busn_res(child, busnr, busnr);
50
51 return child;
52}
53
54static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus)
55{
56 if (physbus != virtbus && list_empty(&virtbus->devices))
57 pci_remove_bus(virtbus);
58}
59
60static int virtfn_add(struct pci_dev *dev, int id, int reset)
61{
62 int i;
63 int rc = -ENOMEM;
64 u64 size;
65 char buf[VIRTFN_ID_LEN];
66 struct pci_dev *virtfn;
67 struct resource *res;
68 struct pci_sriov *iov = dev->sriov;
69 struct pci_bus *bus;
70
71 mutex_lock(&iov->dev->sriov->lock);
72 bus = virtfn_add_bus(dev->bus, virtfn_bus(dev, id));
73 if (!bus)
74 goto failed;
75
76 virtfn = pci_alloc_dev(bus);
77 if (!virtfn)
78 goto failed0;
79
80 virtfn->devfn = virtfn_devfn(dev, id);
81 virtfn->vendor = dev->vendor;
82 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_DID, &virtfn->device);
83 pci_setup_device(virtfn);
84 virtfn->dev.parent = dev->dev.parent;
85 virtfn->physfn = pci_dev_get(dev);
86 virtfn->is_virtfn = 1;
87 virtfn->multifunction = 0;
88
89 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
90 res = dev->resource + PCI_IOV_RESOURCES + i;
91 if (!res->parent)
92 continue;
93 virtfn->resource[i].name = pci_name(virtfn);
94 virtfn->resource[i].flags = res->flags;
95 size = resource_size(res);
96 do_div(size, iov->total_VFs);
97 virtfn->resource[i].start = res->start + size * id;
98 virtfn->resource[i].end = virtfn->resource[i].start + size - 1;
99 rc = request_resource(res, &virtfn->resource[i]);
100 BUG_ON(rc);
101 }
102
103 if (reset)
104 __pci_reset_function(virtfn);
105
106 pci_device_add(virtfn, virtfn->bus);
107 mutex_unlock(&iov->dev->sriov->lock);
108
109 rc = pci_bus_add_device(virtfn);
110 sprintf(buf, "virtfn%u", id);
111 rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
112 if (rc)
113 goto failed1;
114 rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");
115 if (rc)
116 goto failed2;
117
118 kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);
119
120 return 0;
121
122failed2:
123 sysfs_remove_link(&dev->dev.kobj, buf);
124failed1:
125 pci_dev_put(dev);
126 mutex_lock(&iov->dev->sriov->lock);
127 pci_stop_and_remove_bus_device(virtfn);
128failed0:
129 virtfn_remove_bus(dev->bus, bus);
130failed:
131 mutex_unlock(&iov->dev->sriov->lock);
132
133 return rc;
134}
135
136static void virtfn_remove(struct pci_dev *dev, int id, int reset)
137{
138 char buf[VIRTFN_ID_LEN];
139 struct pci_dev *virtfn;
140 struct pci_sriov *iov = dev->sriov;
141
142 virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus),
143 virtfn_bus(dev, id),
144 virtfn_devfn(dev, id));
145 if (!virtfn)
146 return;
147
148 if (reset) {
149 device_release_driver(&virtfn->dev);
150 __pci_reset_function(virtfn);
151 }
152
153 sprintf(buf, "virtfn%u", id);
154 sysfs_remove_link(&dev->dev.kobj, buf);
155 /*
156 * pci_stop_dev() could have been called for this virtfn already,
157 * so the directory for the virtfn may have been removed before.
158 * Double check to avoid spurious sysfs warnings.
159 */
160 if (virtfn->dev.kobj.sd)
161 sysfs_remove_link(&virtfn->dev.kobj, "physfn");
162
163 mutex_lock(&iov->dev->sriov->lock);
164 pci_stop_and_remove_bus_device(virtfn);
165 virtfn_remove_bus(dev->bus, virtfn->bus);
166 mutex_unlock(&iov->dev->sriov->lock);
167
168 /* balance pci_get_domain_bus_and_slot() */
169 pci_dev_put(virtfn);
170 pci_dev_put(dev);
171}
172
173static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
174{
175 int rc;
176 int i, j;
177 int nres;
178 u16 offset, stride, initial;
179 struct resource *res;
180 struct pci_dev *pdev;
181 struct pci_sriov *iov = dev->sriov;
182 int bars = 0;
183
184 if (!nr_virtfn)
185 return 0;
186
187 if (iov->num_VFs)
188 return -EINVAL;
189
190 pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial);
191 if (initial > iov->total_VFs ||
192 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total_VFs)))
193 return -EIO;
194
195 if (nr_virtfn < 0 || nr_virtfn > iov->total_VFs ||
196 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
197 return -EINVAL;
198
199 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &offset);
200 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &stride);
201 if (!offset || (nr_virtfn > 1 && !stride))
202 return -EIO;
203
204 nres = 0;
205 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
206 bars |= (1 << (i + PCI_IOV_RESOURCES));
207 res = dev->resource + PCI_IOV_RESOURCES + i;
208 if (res->parent)
209 nres++;
210 }
211 if (nres != iov->nres) {
212 dev_err(&dev->dev, "not enough MMIO resources for SR-IOV\n");
213 return -ENOMEM;
214 }
215
216 iov->offset = offset;
217 iov->stride = stride;
218
219 if (virtfn_bus(dev, nr_virtfn - 1) > dev->bus->busn_res.end) {
220 dev_err(&dev->dev, "SR-IOV: bus number out of range\n");
221 return -ENOMEM;
222 }
223
224 if (pci_enable_resources(dev, bars)) {
225 dev_err(&dev->dev, "SR-IOV: IOV BARS not allocated\n");
226 return -ENOMEM;
227 }
228
229 if (iov->link != dev->devfn) {
230 pdev = pci_get_slot(dev->bus, iov->link);
231 if (!pdev)
232 return -ENODEV;
233
234 if (!pdev->is_physfn) {
235 pci_dev_put(pdev);
236 return -ENOSYS;
237 }
238
239 rc = sysfs_create_link(&dev->dev.kobj,
240 &pdev->dev.kobj, "dep_link");
241 pci_dev_put(pdev);
242 if (rc)
243 return rc;
244 }
245
246 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn);
247 iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
248 pci_cfg_access_lock(dev);
249 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
250 msleep(100);
251 pci_cfg_access_unlock(dev);
252
253 iov->initial_VFs = initial;
254 if (nr_virtfn < initial)
255 initial = nr_virtfn;
256
257 for (i = 0; i < initial; i++) {
258 rc = virtfn_add(dev, i, 0);
259 if (rc)
260 goto failed;
261 }
262
263 kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE);
264 iov->num_VFs = nr_virtfn;
265
266 return 0;
267
268failed:
269 for (j = 0; j < i; j++)
270 virtfn_remove(dev, j, 0);
271
272 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
273 pci_cfg_access_lock(dev);
274 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
275 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, 0);
276 ssleep(1);
277 pci_cfg_access_unlock(dev);
278
279 if (iov->link != dev->devfn)
280 sysfs_remove_link(&dev->dev.kobj, "dep_link");
281
282 return rc;
283}
284
285static void sriov_disable(struct pci_dev *dev)
286{
287 int i;
288 struct pci_sriov *iov = dev->sriov;
289
290 if (!iov->num_VFs)
291 return;
292
293 for (i = 0; i < iov->num_VFs; i++)
294 virtfn_remove(dev, i, 0);
295
296 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
297 pci_cfg_access_lock(dev);
298 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
299 ssleep(1);
300 pci_cfg_access_unlock(dev);
301
302 if (iov->link != dev->devfn)
303 sysfs_remove_link(&dev->dev.kobj, "dep_link");
304
305 iov->num_VFs = 0;
306 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, 0);
307}
308
309static int sriov_init(struct pci_dev *dev, int pos)
310{
311 int i;
312 int rc;
313 int nres;
314 u32 pgsz;
315 u16 ctrl, total, offset, stride;
316 struct pci_sriov *iov;
317 struct resource *res;
318 struct pci_dev *pdev;
319
320 if (pci_pcie_type(dev) != PCI_EXP_TYPE_RC_END &&
321 pci_pcie_type(dev) != PCI_EXP_TYPE_ENDPOINT)
322 return -ENODEV;
323
324 pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl);
325 if (ctrl & PCI_SRIOV_CTRL_VFE) {
326 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0);
327 ssleep(1);
328 }
329
330 pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total);
331 if (!total)
332 return 0;
333
334 ctrl = 0;
335 list_for_each_entry(pdev, &dev->bus->devices, bus_list)
336 if (pdev->is_physfn)
337 goto found;
338
339 pdev = NULL;
340 if (pci_ari_enabled(dev->bus))
341 ctrl |= PCI_SRIOV_CTRL_ARI;
342
343found:
344 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl);
345 pci_write_config_word(dev, pos + PCI_SRIOV_NUM_VF, 0);
346 pci_read_config_word(dev, pos + PCI_SRIOV_VF_OFFSET, &offset);
347 pci_read_config_word(dev, pos + PCI_SRIOV_VF_STRIDE, &stride);
348 if (!offset || (total > 1 && !stride))
349 return -EIO;
350
351 pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz);
352 i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0;
353 pgsz &= ~((1 << i) - 1);
354 if (!pgsz)
355 return -EIO;
356
357 pgsz &= ~(pgsz - 1);
358 pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz);
359
360 nres = 0;
361 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
362 res = dev->resource + PCI_IOV_RESOURCES + i;
363 i += __pci_read_base(dev, pci_bar_unknown, res,
364 pos + PCI_SRIOV_BAR + i * 4);
365 if (!res->flags)
366 continue;
367 if (resource_size(res) & (PAGE_SIZE - 1)) {
368 rc = -EIO;
369 goto failed;
370 }
371 res->end = res->start + resource_size(res) * total - 1;
372 nres++;
373 }
374
375 iov = kzalloc(sizeof(*iov), GFP_KERNEL);
376 if (!iov) {
377 rc = -ENOMEM;
378 goto failed;
379 }
380
381 iov->pos = pos;
382 iov->nres = nres;
383 iov->ctrl = ctrl;
384 iov->total_VFs = total;
385 iov->offset = offset;
386 iov->stride = stride;
387 iov->pgsz = pgsz;
388 iov->self = dev;
389 pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap);
390 pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link);
391 if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END)
392 iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link);
393
394 if (pdev)
395 iov->dev = pci_dev_get(pdev);
396 else
397 iov->dev = dev;
398
399 mutex_init(&iov->lock);
400
401 dev->sriov = iov;
402 dev->is_physfn = 1;
403
404 return 0;
405
406failed:
407 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
408 res = dev->resource + PCI_IOV_RESOURCES + i;
409 res->flags = 0;
410 }
411
412 return rc;
413}
414
415static void sriov_release(struct pci_dev *dev)
416{
417 BUG_ON(dev->sriov->num_VFs);
418
419 if (dev != dev->sriov->dev)
420 pci_dev_put(dev->sriov->dev);
421
422 mutex_destroy(&dev->sriov->lock);
423
424 kfree(dev->sriov);
425 dev->sriov = NULL;
426}
427
428static void sriov_restore_state(struct pci_dev *dev)
429{
430 int i;
431 u16 ctrl;
432 struct pci_sriov *iov = dev->sriov;
433
434 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl);
435 if (ctrl & PCI_SRIOV_CTRL_VFE)
436 return;
437
438 for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++)
439 pci_update_resource(dev, i);
440
441 pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
442 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, iov->num_VFs);
443 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
444 if (iov->ctrl & PCI_SRIOV_CTRL_VFE)
445 msleep(100);
446}
447
448/**
449 * pci_iov_init - initialize the IOV capability
450 * @dev: the PCI device
451 *
452 * Returns 0 on success, or negative on failure.
453 */
454int pci_iov_init(struct pci_dev *dev)
455{
456 int pos;
457
458 if (!pci_is_pcie(dev))
459 return -ENODEV;
460
461 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV);
462 if (pos)
463 return sriov_init(dev, pos);
464
465 return -ENODEV;
466}
467
468/**
469 * pci_iov_release - release resources used by the IOV capability
470 * @dev: the PCI device
471 */
472void pci_iov_release(struct pci_dev *dev)
473{
474 if (dev->is_physfn)
475 sriov_release(dev);
476}
477
478/**
479 * pci_iov_resource_bar - get position of the SR-IOV BAR
480 * @dev: the PCI device
481 * @resno: the resource number
482 * @type: the BAR type to be filled in
483 *
484 * Returns position of the BAR encapsulated in the SR-IOV capability.
485 */
486int pci_iov_resource_bar(struct pci_dev *dev, int resno,
487 enum pci_bar_type *type)
488{
489 if (resno < PCI_IOV_RESOURCES || resno > PCI_IOV_RESOURCE_END)
490 return 0;
491
492 BUG_ON(!dev->is_physfn);
493
494 *type = pci_bar_unknown;
495
496 return dev->sriov->pos + PCI_SRIOV_BAR +
497 4 * (resno - PCI_IOV_RESOURCES);
498}
499
500/**
501 * pci_sriov_resource_alignment - get resource alignment for VF BAR
502 * @dev: the PCI device
503 * @resno: the resource number
504 *
505 * Returns the alignment of the VF BAR found in the SR-IOV capability.
506 * This is not the same as the resource size which is defined as
507 * the VF BAR size multiplied by the number of VFs. The alignment
508 * is just the VF BAR size.
509 */
510resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno)
511{
512 struct resource tmp;
513 enum pci_bar_type type;
514 int reg = pci_iov_resource_bar(dev, resno, &type);
515
516 if (!reg)
517 return 0;
518
519 __pci_read_base(dev, type, &tmp, reg);
520 return resource_alignment(&tmp);
521}
522
523/**
524 * pci_restore_iov_state - restore the state of the IOV capability
525 * @dev: the PCI device
526 */
527void pci_restore_iov_state(struct pci_dev *dev)
528{
529 if (dev->is_physfn)
530 sriov_restore_state(dev);
531}
532
533/**
534 * pci_iov_bus_range - find bus range used by Virtual Function
535 * @bus: the PCI bus
536 *
537 * Returns max number of buses (exclude current one) used by Virtual
538 * Functions.
539 */
540int pci_iov_bus_range(struct pci_bus *bus)
541{
542 int max = 0;
543 u8 busnr;
544 struct pci_dev *dev;
545
546 list_for_each_entry(dev, &bus->devices, bus_list) {
547 if (!dev->is_physfn)
548 continue;
549 busnr = virtfn_bus(dev, dev->sriov->total_VFs - 1);
550 if (busnr > max)
551 max = busnr;
552 }
553
554 return max ? max - bus->number : 0;
555}
556
557/**
558 * pci_enable_sriov - enable the SR-IOV capability
559 * @dev: the PCI device
560 * @nr_virtfn: number of virtual functions to enable
561 *
562 * Returns 0 on success, or negative on failure.
563 */
564int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
565{
566 might_sleep();
567
568 if (!dev->is_physfn)
569 return -ENOSYS;
570
571 return sriov_enable(dev, nr_virtfn);
572}
573EXPORT_SYMBOL_GPL(pci_enable_sriov);
574
575/**
576 * pci_disable_sriov - disable the SR-IOV capability
577 * @dev: the PCI device
578 */
579void pci_disable_sriov(struct pci_dev *dev)
580{
581 might_sleep();
582
583 if (!dev->is_physfn)
584 return;
585
586 sriov_disable(dev);
587}
588EXPORT_SYMBOL_GPL(pci_disable_sriov);
589
590/**
591 * pci_num_vf - return number of VFs associated with a PF device_release_driver
592 * @dev: the PCI device
593 *
594 * Returns number of VFs, or 0 if SR-IOV is not enabled.
595 */
596int pci_num_vf(struct pci_dev *dev)
597{
598 if (!dev->is_physfn)
599 return 0;
600
601 return dev->sriov->num_VFs;
602}
603EXPORT_SYMBOL_GPL(pci_num_vf);
604
605/**
606 * pci_vfs_assigned - returns number of VFs are assigned to a guest
607 * @dev: the PCI device
608 *
609 * Returns number of VFs belonging to this device that are assigned to a guest.
610 * If device is not a physical function returns 0.
611 */
612int pci_vfs_assigned(struct pci_dev *dev)
613{
614 struct pci_dev *vfdev;
615 unsigned int vfs_assigned = 0;
616 unsigned short dev_id;
617
618 /* only search if we are a PF */
619 if (!dev->is_physfn)
620 return 0;
621
622 /*
623 * determine the device ID for the VFs, the vendor ID will be the
624 * same as the PF so there is no need to check for that one
625 */
626 pci_read_config_word(dev, dev->sriov->pos + PCI_SRIOV_VF_DID, &dev_id);
627
628 /* loop through all the VFs to see if we own any that are assigned */
629 vfdev = pci_get_device(dev->vendor, dev_id, NULL);
630 while (vfdev) {
631 /*
632 * It is considered assigned if it is a virtual function with
633 * our dev as the physical function and the assigned bit is set
634 */
635 if (vfdev->is_virtfn && (vfdev->physfn == dev) &&
636 (vfdev->dev_flags & PCI_DEV_FLAGS_ASSIGNED))
637 vfs_assigned++;
638
639 vfdev = pci_get_device(dev->vendor, dev_id, vfdev);
640 }
641
642 return vfs_assigned;
643}
644EXPORT_SYMBOL_GPL(pci_vfs_assigned);
645
646/**
647 * pci_sriov_set_totalvfs -- reduce the TotalVFs available
648 * @dev: the PCI PF device
649 * @numvfs: number that should be used for TotalVFs supported
650 *
651 * Should be called from PF driver's probe routine with
652 * device's mutex held.
653 *
654 * Returns 0 if PF is an SRIOV-capable device and
655 * value of numvfs valid. If not a PF return -ENOSYS;
656 * if numvfs is invalid return -EINVAL;
657 * if VFs already enabled, return -EBUSY.
658 */
659int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs)
660{
661 if (!dev->is_physfn)
662 return -ENOSYS;
663 if (numvfs > dev->sriov->total_VFs)
664 return -EINVAL;
665
666 /* Shouldn't change if VFs already enabled */
667 if (dev->sriov->ctrl & PCI_SRIOV_CTRL_VFE)
668 return -EBUSY;
669 else
670 dev->sriov->driver_max_VFs = numvfs;
671
672 return 0;
673}
674EXPORT_SYMBOL_GPL(pci_sriov_set_totalvfs);
675
676/**
677 * pci_sriov_get_totalvfs -- get total VFs supported on this device
678 * @dev: the PCI PF device
679 *
680 * For a PCIe device with SRIOV support, return the PCIe
681 * SRIOV capability value of TotalVFs or the value of driver_max_VFs
682 * if the driver reduced it. Otherwise 0.
683 */
684int pci_sriov_get_totalvfs(struct pci_dev *dev)
685{
686 if (!dev->is_physfn)
687 return 0;
688
689 if (dev->sriov->driver_max_VFs)
690 return dev->sriov->driver_max_VFs;
691
692 return dev->sriov->total_VFs;
693}
694EXPORT_SYMBOL_GPL(pci_sriov_get_totalvfs);