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