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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);
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * PCI Express I/O Virtualization (IOV) support
4 * Single Root IOV 1.0
5 * Address Translation Service 1.0
6 *
7 * Copyright (C) 2009 Intel Corporation, Yu Zhao <yu.zhao@intel.com>
8 */
9
10#include <linux/pci.h>
11#include <linux/slab.h>
12#include <linux/export.h>
13#include <linux/string.h>
14#include <linux/delay.h>
15#include "pci.h"
16
17#define VIRTFN_ID_LEN 16
18
19int pci_iov_virtfn_bus(struct pci_dev *dev, int vf_id)
20{
21 if (!dev->is_physfn)
22 return -EINVAL;
23 return dev->bus->number + ((dev->devfn + dev->sriov->offset +
24 dev->sriov->stride * vf_id) >> 8);
25}
26
27int pci_iov_virtfn_devfn(struct pci_dev *dev, int vf_id)
28{
29 if (!dev->is_physfn)
30 return -EINVAL;
31 return (dev->devfn + dev->sriov->offset +
32 dev->sriov->stride * vf_id) & 0xff;
33}
34EXPORT_SYMBOL_GPL(pci_iov_virtfn_devfn);
35
36int pci_iov_vf_id(struct pci_dev *dev)
37{
38 struct pci_dev *pf;
39
40 if (!dev->is_virtfn)
41 return -EINVAL;
42
43 pf = pci_physfn(dev);
44 return (((dev->bus->number << 8) + dev->devfn) -
45 ((pf->bus->number << 8) + pf->devfn + pf->sriov->offset)) /
46 pf->sriov->stride;
47}
48EXPORT_SYMBOL_GPL(pci_iov_vf_id);
49
50/**
51 * pci_iov_get_pf_drvdata - Return the drvdata of a PF
52 * @dev: VF pci_dev
53 * @pf_driver: Device driver required to own the PF
54 *
55 * This must be called from a context that ensures that a VF driver is attached.
56 * The value returned is invalid once the VF driver completes its remove()
57 * callback.
58 *
59 * Locking is achieved by the driver core. A VF driver cannot be probed until
60 * pci_enable_sriov() is called and pci_disable_sriov() does not return until
61 * all VF drivers have completed their remove().
62 *
63 * The PF driver must call pci_disable_sriov() before it begins to destroy the
64 * drvdata.
65 */
66void *pci_iov_get_pf_drvdata(struct pci_dev *dev, struct pci_driver *pf_driver)
67{
68 struct pci_dev *pf_dev;
69
70 if (!dev->is_virtfn)
71 return ERR_PTR(-EINVAL);
72 pf_dev = dev->physfn;
73 if (pf_dev->driver != pf_driver)
74 return ERR_PTR(-EINVAL);
75 return pci_get_drvdata(pf_dev);
76}
77EXPORT_SYMBOL_GPL(pci_iov_get_pf_drvdata);
78
79/*
80 * Per SR-IOV spec sec 3.3.10 and 3.3.11, First VF Offset and VF Stride may
81 * change when NumVFs changes.
82 *
83 * Update iov->offset and iov->stride when NumVFs is written.
84 */
85static inline void pci_iov_set_numvfs(struct pci_dev *dev, int nr_virtfn)
86{
87 struct pci_sriov *iov = dev->sriov;
88
89 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn);
90 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &iov->offset);
91 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &iov->stride);
92}
93
94/*
95 * The PF consumes one bus number. NumVFs, First VF Offset, and VF Stride
96 * determine how many additional bus numbers will be consumed by VFs.
97 *
98 * Iterate over all valid NumVFs, validate offset and stride, and calculate
99 * the maximum number of bus numbers that could ever be required.
100 */
101static int compute_max_vf_buses(struct pci_dev *dev)
102{
103 struct pci_sriov *iov = dev->sriov;
104 int nr_virtfn, busnr, rc = 0;
105
106 for (nr_virtfn = iov->total_VFs; nr_virtfn; nr_virtfn--) {
107 pci_iov_set_numvfs(dev, nr_virtfn);
108 if (!iov->offset || (nr_virtfn > 1 && !iov->stride)) {
109 rc = -EIO;
110 goto out;
111 }
112
113 busnr = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
114 if (busnr > iov->max_VF_buses)
115 iov->max_VF_buses = busnr;
116 }
117
118out:
119 pci_iov_set_numvfs(dev, 0);
120 return rc;
121}
122
123static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr)
124{
125 struct pci_bus *child;
126
127 if (bus->number == busnr)
128 return bus;
129
130 child = pci_find_bus(pci_domain_nr(bus), busnr);
131 if (child)
132 return child;
133
134 child = pci_add_new_bus(bus, NULL, busnr);
135 if (!child)
136 return NULL;
137
138 pci_bus_insert_busn_res(child, busnr, busnr);
139
140 return child;
141}
142
143static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus)
144{
145 if (physbus != virtbus && list_empty(&virtbus->devices))
146 pci_remove_bus(virtbus);
147}
148
149resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)
150{
151 if (!dev->is_physfn)
152 return 0;
153
154 return dev->sriov->barsz[resno - PCI_IOV_RESOURCES];
155}
156
157static void pci_read_vf_config_common(struct pci_dev *virtfn)
158{
159 struct pci_dev *physfn = virtfn->physfn;
160
161 /*
162 * Some config registers are the same across all associated VFs.
163 * Read them once from VF0 so we can skip reading them from the
164 * other VFs.
165 *
166 * PCIe r4.0, sec 9.3.4.1, technically doesn't require all VFs to
167 * have the same Revision ID and Subsystem ID, but we assume they
168 * do.
169 */
170 pci_read_config_dword(virtfn, PCI_CLASS_REVISION,
171 &physfn->sriov->class);
172 pci_read_config_byte(virtfn, PCI_HEADER_TYPE,
173 &physfn->sriov->hdr_type);
174 pci_read_config_word(virtfn, PCI_SUBSYSTEM_VENDOR_ID,
175 &physfn->sriov->subsystem_vendor);
176 pci_read_config_word(virtfn, PCI_SUBSYSTEM_ID,
177 &physfn->sriov->subsystem_device);
178}
179
180int pci_iov_sysfs_link(struct pci_dev *dev,
181 struct pci_dev *virtfn, int id)
182{
183 char buf[VIRTFN_ID_LEN];
184 int rc;
185
186 sprintf(buf, "virtfn%u", id);
187 rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
188 if (rc)
189 goto failed;
190 rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");
191 if (rc)
192 goto failed1;
193
194 kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);
195
196 return 0;
197
198failed1:
199 sysfs_remove_link(&dev->dev.kobj, buf);
200failed:
201 return rc;
202}
203
204#ifdef CONFIG_PCI_MSI
205static ssize_t sriov_vf_total_msix_show(struct device *dev,
206 struct device_attribute *attr,
207 char *buf)
208{
209 struct pci_dev *pdev = to_pci_dev(dev);
210 u32 vf_total_msix = 0;
211
212 device_lock(dev);
213 if (!pdev->driver || !pdev->driver->sriov_get_vf_total_msix)
214 goto unlock;
215
216 vf_total_msix = pdev->driver->sriov_get_vf_total_msix(pdev);
217unlock:
218 device_unlock(dev);
219 return sysfs_emit(buf, "%u\n", vf_total_msix);
220}
221static DEVICE_ATTR_RO(sriov_vf_total_msix);
222
223static ssize_t sriov_vf_msix_count_store(struct device *dev,
224 struct device_attribute *attr,
225 const char *buf, size_t count)
226{
227 struct pci_dev *vf_dev = to_pci_dev(dev);
228 struct pci_dev *pdev = pci_physfn(vf_dev);
229 int val, ret = 0;
230
231 if (kstrtoint(buf, 0, &val) < 0)
232 return -EINVAL;
233
234 if (val < 0)
235 return -EINVAL;
236
237 device_lock(&pdev->dev);
238 if (!pdev->driver || !pdev->driver->sriov_set_msix_vec_count) {
239 ret = -EOPNOTSUPP;
240 goto err_pdev;
241 }
242
243 device_lock(&vf_dev->dev);
244 if (vf_dev->driver) {
245 /*
246 * A driver is already attached to this VF and has configured
247 * itself based on the current MSI-X vector count. Changing
248 * the vector size could mess up the driver, so block it.
249 */
250 ret = -EBUSY;
251 goto err_dev;
252 }
253
254 ret = pdev->driver->sriov_set_msix_vec_count(vf_dev, val);
255
256err_dev:
257 device_unlock(&vf_dev->dev);
258err_pdev:
259 device_unlock(&pdev->dev);
260 return ret ? : count;
261}
262static DEVICE_ATTR_WO(sriov_vf_msix_count);
263#endif
264
265static struct attribute *sriov_vf_dev_attrs[] = {
266#ifdef CONFIG_PCI_MSI
267 &dev_attr_sriov_vf_msix_count.attr,
268#endif
269 NULL,
270};
271
272static umode_t sriov_vf_attrs_are_visible(struct kobject *kobj,
273 struct attribute *a, int n)
274{
275 struct device *dev = kobj_to_dev(kobj);
276 struct pci_dev *pdev = to_pci_dev(dev);
277
278 if (!pdev->is_virtfn)
279 return 0;
280
281 return a->mode;
282}
283
284const struct attribute_group sriov_vf_dev_attr_group = {
285 .attrs = sriov_vf_dev_attrs,
286 .is_visible = sriov_vf_attrs_are_visible,
287};
288
289int pci_iov_add_virtfn(struct pci_dev *dev, int id)
290{
291 int i;
292 int rc = -ENOMEM;
293 u64 size;
294 struct pci_dev *virtfn;
295 struct resource *res;
296 struct pci_sriov *iov = dev->sriov;
297 struct pci_bus *bus;
298
299 bus = virtfn_add_bus(dev->bus, pci_iov_virtfn_bus(dev, id));
300 if (!bus)
301 goto failed;
302
303 virtfn = pci_alloc_dev(bus);
304 if (!virtfn)
305 goto failed0;
306
307 virtfn->devfn = pci_iov_virtfn_devfn(dev, id);
308 virtfn->vendor = dev->vendor;
309 virtfn->device = iov->vf_device;
310 virtfn->is_virtfn = 1;
311 virtfn->physfn = pci_dev_get(dev);
312 virtfn->no_command_memory = 1;
313
314 if (id == 0)
315 pci_read_vf_config_common(virtfn);
316
317 rc = pci_setup_device(virtfn);
318 if (rc)
319 goto failed1;
320
321 virtfn->dev.parent = dev->dev.parent;
322 virtfn->multifunction = 0;
323
324 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
325 res = &dev->resource[i + PCI_IOV_RESOURCES];
326 if (!res->parent)
327 continue;
328 virtfn->resource[i].name = pci_name(virtfn);
329 virtfn->resource[i].flags = res->flags;
330 size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);
331 virtfn->resource[i].start = res->start + size * id;
332 virtfn->resource[i].end = virtfn->resource[i].start + size - 1;
333 rc = request_resource(res, &virtfn->resource[i]);
334 BUG_ON(rc);
335 }
336
337 pci_device_add(virtfn, virtfn->bus);
338 rc = pci_iov_sysfs_link(dev, virtfn, id);
339 if (rc)
340 goto failed1;
341
342 pci_bus_add_device(virtfn);
343
344 return 0;
345
346failed1:
347 pci_stop_and_remove_bus_device(virtfn);
348 pci_dev_put(dev);
349failed0:
350 virtfn_remove_bus(dev->bus, bus);
351failed:
352
353 return rc;
354}
355
356void pci_iov_remove_virtfn(struct pci_dev *dev, int id)
357{
358 char buf[VIRTFN_ID_LEN];
359 struct pci_dev *virtfn;
360
361 virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus),
362 pci_iov_virtfn_bus(dev, id),
363 pci_iov_virtfn_devfn(dev, id));
364 if (!virtfn)
365 return;
366
367 sprintf(buf, "virtfn%u", id);
368 sysfs_remove_link(&dev->dev.kobj, buf);
369 /*
370 * pci_stop_dev() could have been called for this virtfn already,
371 * so the directory for the virtfn may have been removed before.
372 * Double check to avoid spurious sysfs warnings.
373 */
374 if (virtfn->dev.kobj.sd)
375 sysfs_remove_link(&virtfn->dev.kobj, "physfn");
376
377 pci_stop_and_remove_bus_device(virtfn);
378 virtfn_remove_bus(dev->bus, virtfn->bus);
379
380 /* balance pci_get_domain_bus_and_slot() */
381 pci_dev_put(virtfn);
382 pci_dev_put(dev);
383}
384
385static ssize_t sriov_totalvfs_show(struct device *dev,
386 struct device_attribute *attr,
387 char *buf)
388{
389 struct pci_dev *pdev = to_pci_dev(dev);
390
391 return sysfs_emit(buf, "%u\n", pci_sriov_get_totalvfs(pdev));
392}
393
394static ssize_t sriov_numvfs_show(struct device *dev,
395 struct device_attribute *attr,
396 char *buf)
397{
398 struct pci_dev *pdev = to_pci_dev(dev);
399 u16 num_vfs;
400
401 /* Serialize vs sriov_numvfs_store() so readers see valid num_VFs */
402 device_lock(&pdev->dev);
403 num_vfs = pdev->sriov->num_VFs;
404 device_unlock(&pdev->dev);
405
406 return sysfs_emit(buf, "%u\n", num_vfs);
407}
408
409/*
410 * num_vfs > 0; number of VFs to enable
411 * num_vfs = 0; disable all VFs
412 *
413 * Note: SRIOV spec does not allow partial VF
414 * disable, so it's all or none.
415 */
416static ssize_t sriov_numvfs_store(struct device *dev,
417 struct device_attribute *attr,
418 const char *buf, size_t count)
419{
420 struct pci_dev *pdev = to_pci_dev(dev);
421 int ret = 0;
422 u16 num_vfs;
423
424 if (kstrtou16(buf, 0, &num_vfs) < 0)
425 return -EINVAL;
426
427 if (num_vfs > pci_sriov_get_totalvfs(pdev))
428 return -ERANGE;
429
430 device_lock(&pdev->dev);
431
432 if (num_vfs == pdev->sriov->num_VFs)
433 goto exit;
434
435 /* is PF driver loaded */
436 if (!pdev->driver) {
437 pci_info(pdev, "no driver bound to device; cannot configure SR-IOV\n");
438 ret = -ENOENT;
439 goto exit;
440 }
441
442 /* is PF driver loaded w/callback */
443 if (!pdev->driver->sriov_configure) {
444 pci_info(pdev, "driver does not support SR-IOV configuration via sysfs\n");
445 ret = -ENOENT;
446 goto exit;
447 }
448
449 if (num_vfs == 0) {
450 /* disable VFs */
451 ret = pdev->driver->sriov_configure(pdev, 0);
452 goto exit;
453 }
454
455 /* enable VFs */
456 if (pdev->sriov->num_VFs) {
457 pci_warn(pdev, "%d VFs already enabled. Disable before enabling %d VFs\n",
458 pdev->sriov->num_VFs, num_vfs);
459 ret = -EBUSY;
460 goto exit;
461 }
462
463 ret = pdev->driver->sriov_configure(pdev, num_vfs);
464 if (ret < 0)
465 goto exit;
466
467 if (ret != num_vfs)
468 pci_warn(pdev, "%d VFs requested; only %d enabled\n",
469 num_vfs, ret);
470
471exit:
472 device_unlock(&pdev->dev);
473
474 if (ret < 0)
475 return ret;
476
477 return count;
478}
479
480static ssize_t sriov_offset_show(struct device *dev,
481 struct device_attribute *attr,
482 char *buf)
483{
484 struct pci_dev *pdev = to_pci_dev(dev);
485
486 return sysfs_emit(buf, "%u\n", pdev->sriov->offset);
487}
488
489static ssize_t sriov_stride_show(struct device *dev,
490 struct device_attribute *attr,
491 char *buf)
492{
493 struct pci_dev *pdev = to_pci_dev(dev);
494
495 return sysfs_emit(buf, "%u\n", pdev->sriov->stride);
496}
497
498static ssize_t sriov_vf_device_show(struct device *dev,
499 struct device_attribute *attr,
500 char *buf)
501{
502 struct pci_dev *pdev = to_pci_dev(dev);
503
504 return sysfs_emit(buf, "%x\n", pdev->sriov->vf_device);
505}
506
507static ssize_t sriov_drivers_autoprobe_show(struct device *dev,
508 struct device_attribute *attr,
509 char *buf)
510{
511 struct pci_dev *pdev = to_pci_dev(dev);
512
513 return sysfs_emit(buf, "%u\n", pdev->sriov->drivers_autoprobe);
514}
515
516static ssize_t sriov_drivers_autoprobe_store(struct device *dev,
517 struct device_attribute *attr,
518 const char *buf, size_t count)
519{
520 struct pci_dev *pdev = to_pci_dev(dev);
521 bool drivers_autoprobe;
522
523 if (kstrtobool(buf, &drivers_autoprobe) < 0)
524 return -EINVAL;
525
526 pdev->sriov->drivers_autoprobe = drivers_autoprobe;
527
528 return count;
529}
530
531static DEVICE_ATTR_RO(sriov_totalvfs);
532static DEVICE_ATTR_RW(sriov_numvfs);
533static DEVICE_ATTR_RO(sriov_offset);
534static DEVICE_ATTR_RO(sriov_stride);
535static DEVICE_ATTR_RO(sriov_vf_device);
536static DEVICE_ATTR_RW(sriov_drivers_autoprobe);
537
538static struct attribute *sriov_pf_dev_attrs[] = {
539 &dev_attr_sriov_totalvfs.attr,
540 &dev_attr_sriov_numvfs.attr,
541 &dev_attr_sriov_offset.attr,
542 &dev_attr_sriov_stride.attr,
543 &dev_attr_sriov_vf_device.attr,
544 &dev_attr_sriov_drivers_autoprobe.attr,
545#ifdef CONFIG_PCI_MSI
546 &dev_attr_sriov_vf_total_msix.attr,
547#endif
548 NULL,
549};
550
551static umode_t sriov_pf_attrs_are_visible(struct kobject *kobj,
552 struct attribute *a, int n)
553{
554 struct device *dev = kobj_to_dev(kobj);
555
556 if (!dev_is_pf(dev))
557 return 0;
558
559 return a->mode;
560}
561
562const struct attribute_group sriov_pf_dev_attr_group = {
563 .attrs = sriov_pf_dev_attrs,
564 .is_visible = sriov_pf_attrs_are_visible,
565};
566
567int __weak pcibios_sriov_enable(struct pci_dev *pdev, u16 num_vfs)
568{
569 return 0;
570}
571
572int __weak pcibios_sriov_disable(struct pci_dev *pdev)
573{
574 return 0;
575}
576
577static int sriov_add_vfs(struct pci_dev *dev, u16 num_vfs)
578{
579 unsigned int i;
580 int rc;
581
582 if (dev->no_vf_scan)
583 return 0;
584
585 for (i = 0; i < num_vfs; i++) {
586 rc = pci_iov_add_virtfn(dev, i);
587 if (rc)
588 goto failed;
589 }
590 return 0;
591failed:
592 while (i--)
593 pci_iov_remove_virtfn(dev, i);
594
595 return rc;
596}
597
598static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
599{
600 int rc;
601 int i;
602 int nres;
603 u16 initial;
604 struct resource *res;
605 struct pci_dev *pdev;
606 struct pci_sriov *iov = dev->sriov;
607 int bars = 0;
608 int bus;
609
610 if (!nr_virtfn)
611 return 0;
612
613 if (iov->num_VFs)
614 return -EINVAL;
615
616 pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial);
617 if (initial > iov->total_VFs ||
618 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total_VFs)))
619 return -EIO;
620
621 if (nr_virtfn < 0 || nr_virtfn > iov->total_VFs ||
622 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
623 return -EINVAL;
624
625 nres = 0;
626 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
627 bars |= (1 << (i + PCI_IOV_RESOURCES));
628 res = &dev->resource[i + PCI_IOV_RESOURCES];
629 if (res->parent)
630 nres++;
631 }
632 if (nres != iov->nres) {
633 pci_err(dev, "not enough MMIO resources for SR-IOV\n");
634 return -ENOMEM;
635 }
636
637 bus = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
638 if (bus > dev->bus->busn_res.end) {
639 pci_err(dev, "can't enable %d VFs (bus %02x out of range of %pR)\n",
640 nr_virtfn, bus, &dev->bus->busn_res);
641 return -ENOMEM;
642 }
643
644 if (pci_enable_resources(dev, bars)) {
645 pci_err(dev, "SR-IOV: IOV BARS not allocated\n");
646 return -ENOMEM;
647 }
648
649 if (iov->link != dev->devfn) {
650 pdev = pci_get_slot(dev->bus, iov->link);
651 if (!pdev)
652 return -ENODEV;
653
654 if (!pdev->is_physfn) {
655 pci_dev_put(pdev);
656 return -ENOSYS;
657 }
658
659 rc = sysfs_create_link(&dev->dev.kobj,
660 &pdev->dev.kobj, "dep_link");
661 pci_dev_put(pdev);
662 if (rc)
663 return rc;
664 }
665
666 iov->initial_VFs = initial;
667 if (nr_virtfn < initial)
668 initial = nr_virtfn;
669
670 rc = pcibios_sriov_enable(dev, initial);
671 if (rc) {
672 pci_err(dev, "failure %d from pcibios_sriov_enable()\n", rc);
673 goto err_pcibios;
674 }
675
676 pci_iov_set_numvfs(dev, nr_virtfn);
677 iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
678 pci_cfg_access_lock(dev);
679 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
680 msleep(100);
681 pci_cfg_access_unlock(dev);
682
683 rc = sriov_add_vfs(dev, initial);
684 if (rc)
685 goto err_pcibios;
686
687 kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE);
688 iov->num_VFs = nr_virtfn;
689
690 return 0;
691
692err_pcibios:
693 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
694 pci_cfg_access_lock(dev);
695 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
696 ssleep(1);
697 pci_cfg_access_unlock(dev);
698
699 pcibios_sriov_disable(dev);
700
701 if (iov->link != dev->devfn)
702 sysfs_remove_link(&dev->dev.kobj, "dep_link");
703
704 pci_iov_set_numvfs(dev, 0);
705 return rc;
706}
707
708static void sriov_del_vfs(struct pci_dev *dev)
709{
710 struct pci_sriov *iov = dev->sriov;
711 int i;
712
713 for (i = 0; i < iov->num_VFs; i++)
714 pci_iov_remove_virtfn(dev, i);
715}
716
717static void sriov_disable(struct pci_dev *dev)
718{
719 struct pci_sriov *iov = dev->sriov;
720
721 if (!iov->num_VFs)
722 return;
723
724 sriov_del_vfs(dev);
725 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
726 pci_cfg_access_lock(dev);
727 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
728 ssleep(1);
729 pci_cfg_access_unlock(dev);
730
731 pcibios_sriov_disable(dev);
732
733 if (iov->link != dev->devfn)
734 sysfs_remove_link(&dev->dev.kobj, "dep_link");
735
736 iov->num_VFs = 0;
737 pci_iov_set_numvfs(dev, 0);
738}
739
740static int sriov_init(struct pci_dev *dev, int pos)
741{
742 int i, bar64;
743 int rc;
744 int nres;
745 u32 pgsz;
746 u16 ctrl, total;
747 struct pci_sriov *iov;
748 struct resource *res;
749 struct pci_dev *pdev;
750
751 pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl);
752 if (ctrl & PCI_SRIOV_CTRL_VFE) {
753 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0);
754 ssleep(1);
755 }
756
757 ctrl = 0;
758 list_for_each_entry(pdev, &dev->bus->devices, bus_list)
759 if (pdev->is_physfn)
760 goto found;
761
762 pdev = NULL;
763 if (pci_ari_enabled(dev->bus))
764 ctrl |= PCI_SRIOV_CTRL_ARI;
765
766found:
767 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl);
768
769 pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total);
770 if (!total)
771 return 0;
772
773 pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz);
774 i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0;
775 pgsz &= ~((1 << i) - 1);
776 if (!pgsz)
777 return -EIO;
778
779 pgsz &= ~(pgsz - 1);
780 pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz);
781
782 iov = kzalloc(sizeof(*iov), GFP_KERNEL);
783 if (!iov)
784 return -ENOMEM;
785
786 nres = 0;
787 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
788 res = &dev->resource[i + PCI_IOV_RESOURCES];
789 /*
790 * If it is already FIXED, don't change it, something
791 * (perhaps EA or header fixups) wants it this way.
792 */
793 if (res->flags & IORESOURCE_PCI_FIXED)
794 bar64 = (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
795 else
796 bar64 = __pci_read_base(dev, pci_bar_unknown, res,
797 pos + PCI_SRIOV_BAR + i * 4);
798 if (!res->flags)
799 continue;
800 if (resource_size(res) & (PAGE_SIZE - 1)) {
801 rc = -EIO;
802 goto failed;
803 }
804 iov->barsz[i] = resource_size(res);
805 res->end = res->start + resource_size(res) * total - 1;
806 pci_info(dev, "VF(n) BAR%d space: %pR (contains BAR%d for %d VFs)\n",
807 i, res, i, total);
808 i += bar64;
809 nres++;
810 }
811
812 iov->pos = pos;
813 iov->nres = nres;
814 iov->ctrl = ctrl;
815 iov->total_VFs = total;
816 iov->driver_max_VFs = total;
817 pci_read_config_word(dev, pos + PCI_SRIOV_VF_DID, &iov->vf_device);
818 iov->pgsz = pgsz;
819 iov->self = dev;
820 iov->drivers_autoprobe = true;
821 pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap);
822 pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link);
823 if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END)
824 iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link);
825
826 if (pdev)
827 iov->dev = pci_dev_get(pdev);
828 else
829 iov->dev = dev;
830
831 dev->sriov = iov;
832 dev->is_physfn = 1;
833 rc = compute_max_vf_buses(dev);
834 if (rc)
835 goto fail_max_buses;
836
837 return 0;
838
839fail_max_buses:
840 dev->sriov = NULL;
841 dev->is_physfn = 0;
842failed:
843 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
844 res = &dev->resource[i + PCI_IOV_RESOURCES];
845 res->flags = 0;
846 }
847
848 kfree(iov);
849 return rc;
850}
851
852static void sriov_release(struct pci_dev *dev)
853{
854 BUG_ON(dev->sriov->num_VFs);
855
856 if (dev != dev->sriov->dev)
857 pci_dev_put(dev->sriov->dev);
858
859 kfree(dev->sriov);
860 dev->sriov = NULL;
861}
862
863static void sriov_restore_state(struct pci_dev *dev)
864{
865 int i;
866 u16 ctrl;
867 struct pci_sriov *iov = dev->sriov;
868
869 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl);
870 if (ctrl & PCI_SRIOV_CTRL_VFE)
871 return;
872
873 /*
874 * Restore PCI_SRIOV_CTRL_ARI before pci_iov_set_numvfs() because
875 * it reads offset & stride, which depend on PCI_SRIOV_CTRL_ARI.
876 */
877 ctrl &= ~PCI_SRIOV_CTRL_ARI;
878 ctrl |= iov->ctrl & PCI_SRIOV_CTRL_ARI;
879 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, ctrl);
880
881 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++)
882 pci_update_resource(dev, i + PCI_IOV_RESOURCES);
883
884 pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
885 pci_iov_set_numvfs(dev, iov->num_VFs);
886 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
887 if (iov->ctrl & PCI_SRIOV_CTRL_VFE)
888 msleep(100);
889}
890
891/**
892 * pci_iov_init - initialize the IOV capability
893 * @dev: the PCI device
894 *
895 * Returns 0 on success, or negative on failure.
896 */
897int pci_iov_init(struct pci_dev *dev)
898{
899 int pos;
900
901 if (!pci_is_pcie(dev))
902 return -ENODEV;
903
904 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV);
905 if (pos)
906 return sriov_init(dev, pos);
907
908 return -ENODEV;
909}
910
911/**
912 * pci_iov_release - release resources used by the IOV capability
913 * @dev: the PCI device
914 */
915void pci_iov_release(struct pci_dev *dev)
916{
917 if (dev->is_physfn)
918 sriov_release(dev);
919}
920
921/**
922 * pci_iov_remove - clean up SR-IOV state after PF driver is detached
923 * @dev: the PCI device
924 */
925void pci_iov_remove(struct pci_dev *dev)
926{
927 struct pci_sriov *iov = dev->sriov;
928
929 if (!dev->is_physfn)
930 return;
931
932 iov->driver_max_VFs = iov->total_VFs;
933 if (iov->num_VFs)
934 pci_warn(dev, "driver left SR-IOV enabled after remove\n");
935}
936
937/**
938 * pci_iov_update_resource - update a VF BAR
939 * @dev: the PCI device
940 * @resno: the resource number
941 *
942 * Update a VF BAR in the SR-IOV capability of a PF.
943 */
944void pci_iov_update_resource(struct pci_dev *dev, int resno)
945{
946 struct pci_sriov *iov = dev->is_physfn ? dev->sriov : NULL;
947 struct resource *res = dev->resource + resno;
948 int vf_bar = resno - PCI_IOV_RESOURCES;
949 struct pci_bus_region region;
950 u16 cmd;
951 u32 new;
952 int reg;
953
954 /*
955 * The generic pci_restore_bars() path calls this for all devices,
956 * including VFs and non-SR-IOV devices. If this is not a PF, we
957 * have nothing to do.
958 */
959 if (!iov)
960 return;
961
962 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &cmd);
963 if ((cmd & PCI_SRIOV_CTRL_VFE) && (cmd & PCI_SRIOV_CTRL_MSE)) {
964 dev_WARN(&dev->dev, "can't update enabled VF BAR%d %pR\n",
965 vf_bar, res);
966 return;
967 }
968
969 /*
970 * Ignore unimplemented BARs, unused resource slots for 64-bit
971 * BARs, and non-movable resources, e.g., those described via
972 * Enhanced Allocation.
973 */
974 if (!res->flags)
975 return;
976
977 if (res->flags & IORESOURCE_UNSET)
978 return;
979
980 if (res->flags & IORESOURCE_PCI_FIXED)
981 return;
982
983 pcibios_resource_to_bus(dev->bus, ®ion, res);
984 new = region.start;
985 new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK;
986
987 reg = iov->pos + PCI_SRIOV_BAR + 4 * vf_bar;
988 pci_write_config_dword(dev, reg, new);
989 if (res->flags & IORESOURCE_MEM_64) {
990 new = region.start >> 16 >> 16;
991 pci_write_config_dword(dev, reg + 4, new);
992 }
993}
994
995resource_size_t __weak pcibios_iov_resource_alignment(struct pci_dev *dev,
996 int resno)
997{
998 return pci_iov_resource_size(dev, resno);
999}
1000
1001/**
1002 * pci_sriov_resource_alignment - get resource alignment for VF BAR
1003 * @dev: the PCI device
1004 * @resno: the resource number
1005 *
1006 * Returns the alignment of the VF BAR found in the SR-IOV capability.
1007 * This is not the same as the resource size which is defined as
1008 * the VF BAR size multiplied by the number of VFs. The alignment
1009 * is just the VF BAR size.
1010 */
1011resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno)
1012{
1013 return pcibios_iov_resource_alignment(dev, resno);
1014}
1015
1016/**
1017 * pci_restore_iov_state - restore the state of the IOV capability
1018 * @dev: the PCI device
1019 */
1020void pci_restore_iov_state(struct pci_dev *dev)
1021{
1022 if (dev->is_physfn)
1023 sriov_restore_state(dev);
1024}
1025
1026/**
1027 * pci_vf_drivers_autoprobe - set PF property drivers_autoprobe for VFs
1028 * @dev: the PCI device
1029 * @auto_probe: set VF drivers auto probe flag
1030 */
1031void pci_vf_drivers_autoprobe(struct pci_dev *dev, bool auto_probe)
1032{
1033 if (dev->is_physfn)
1034 dev->sriov->drivers_autoprobe = auto_probe;
1035}
1036
1037/**
1038 * pci_iov_bus_range - find bus range used by Virtual Function
1039 * @bus: the PCI bus
1040 *
1041 * Returns max number of buses (exclude current one) used by Virtual
1042 * Functions.
1043 */
1044int pci_iov_bus_range(struct pci_bus *bus)
1045{
1046 int max = 0;
1047 struct pci_dev *dev;
1048
1049 list_for_each_entry(dev, &bus->devices, bus_list) {
1050 if (!dev->is_physfn)
1051 continue;
1052 if (dev->sriov->max_VF_buses > max)
1053 max = dev->sriov->max_VF_buses;
1054 }
1055
1056 return max ? max - bus->number : 0;
1057}
1058
1059/**
1060 * pci_enable_sriov - enable the SR-IOV capability
1061 * @dev: the PCI device
1062 * @nr_virtfn: number of virtual functions to enable
1063 *
1064 * Returns 0 on success, or negative on failure.
1065 */
1066int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
1067{
1068 might_sleep();
1069
1070 if (!dev->is_physfn)
1071 return -ENOSYS;
1072
1073 return sriov_enable(dev, nr_virtfn);
1074}
1075EXPORT_SYMBOL_GPL(pci_enable_sriov);
1076
1077/**
1078 * pci_disable_sriov - disable the SR-IOV capability
1079 * @dev: the PCI device
1080 */
1081void pci_disable_sriov(struct pci_dev *dev)
1082{
1083 might_sleep();
1084
1085 if (!dev->is_physfn)
1086 return;
1087
1088 sriov_disable(dev);
1089}
1090EXPORT_SYMBOL_GPL(pci_disable_sriov);
1091
1092/**
1093 * pci_num_vf - return number of VFs associated with a PF device_release_driver
1094 * @dev: the PCI device
1095 *
1096 * Returns number of VFs, or 0 if SR-IOV is not enabled.
1097 */
1098int pci_num_vf(struct pci_dev *dev)
1099{
1100 if (!dev->is_physfn)
1101 return 0;
1102
1103 return dev->sriov->num_VFs;
1104}
1105EXPORT_SYMBOL_GPL(pci_num_vf);
1106
1107/**
1108 * pci_vfs_assigned - returns number of VFs are assigned to a guest
1109 * @dev: the PCI device
1110 *
1111 * Returns number of VFs belonging to this device that are assigned to a guest.
1112 * If device is not a physical function returns 0.
1113 */
1114int pci_vfs_assigned(struct pci_dev *dev)
1115{
1116 struct pci_dev *vfdev;
1117 unsigned int vfs_assigned = 0;
1118 unsigned short dev_id;
1119
1120 /* only search if we are a PF */
1121 if (!dev->is_physfn)
1122 return 0;
1123
1124 /*
1125 * determine the device ID for the VFs, the vendor ID will be the
1126 * same as the PF so there is no need to check for that one
1127 */
1128 dev_id = dev->sriov->vf_device;
1129
1130 /* loop through all the VFs to see if we own any that are assigned */
1131 vfdev = pci_get_device(dev->vendor, dev_id, NULL);
1132 while (vfdev) {
1133 /*
1134 * It is considered assigned if it is a virtual function with
1135 * our dev as the physical function and the assigned bit is set
1136 */
1137 if (vfdev->is_virtfn && (vfdev->physfn == dev) &&
1138 pci_is_dev_assigned(vfdev))
1139 vfs_assigned++;
1140
1141 vfdev = pci_get_device(dev->vendor, dev_id, vfdev);
1142 }
1143
1144 return vfs_assigned;
1145}
1146EXPORT_SYMBOL_GPL(pci_vfs_assigned);
1147
1148/**
1149 * pci_sriov_set_totalvfs -- reduce the TotalVFs available
1150 * @dev: the PCI PF device
1151 * @numvfs: number that should be used for TotalVFs supported
1152 *
1153 * Should be called from PF driver's probe routine with
1154 * device's mutex held.
1155 *
1156 * Returns 0 if PF is an SRIOV-capable device and
1157 * value of numvfs valid. If not a PF return -ENOSYS;
1158 * if numvfs is invalid return -EINVAL;
1159 * if VFs already enabled, return -EBUSY.
1160 */
1161int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs)
1162{
1163 if (!dev->is_physfn)
1164 return -ENOSYS;
1165
1166 if (numvfs > dev->sriov->total_VFs)
1167 return -EINVAL;
1168
1169 /* Shouldn't change if VFs already enabled */
1170 if (dev->sriov->ctrl & PCI_SRIOV_CTRL_VFE)
1171 return -EBUSY;
1172
1173 dev->sriov->driver_max_VFs = numvfs;
1174 return 0;
1175}
1176EXPORT_SYMBOL_GPL(pci_sriov_set_totalvfs);
1177
1178/**
1179 * pci_sriov_get_totalvfs -- get total VFs supported on this device
1180 * @dev: the PCI PF device
1181 *
1182 * For a PCIe device with SRIOV support, return the PCIe
1183 * SRIOV capability value of TotalVFs or the value of driver_max_VFs
1184 * if the driver reduced it. Otherwise 0.
1185 */
1186int pci_sriov_get_totalvfs(struct pci_dev *dev)
1187{
1188 if (!dev->is_physfn)
1189 return 0;
1190
1191 return dev->sriov->driver_max_VFs;
1192}
1193EXPORT_SYMBOL_GPL(pci_sriov_get_totalvfs);
1194
1195/**
1196 * pci_sriov_configure_simple - helper to configure SR-IOV
1197 * @dev: the PCI device
1198 * @nr_virtfn: number of virtual functions to enable, 0 to disable
1199 *
1200 * Enable or disable SR-IOV for devices that don't require any PF setup
1201 * before enabling SR-IOV. Return value is negative on error, or number of
1202 * VFs allocated on success.
1203 */
1204int pci_sriov_configure_simple(struct pci_dev *dev, int nr_virtfn)
1205{
1206 int rc;
1207
1208 might_sleep();
1209
1210 if (!dev->is_physfn)
1211 return -ENODEV;
1212
1213 if (pci_vfs_assigned(dev)) {
1214 pci_warn(dev, "Cannot modify SR-IOV while VFs are assigned\n");
1215 return -EPERM;
1216 }
1217
1218 if (nr_virtfn == 0) {
1219 sriov_disable(dev);
1220 return 0;
1221 }
1222
1223 rc = sriov_enable(dev, nr_virtfn);
1224 if (rc < 0)
1225 return rc;
1226
1227 return nr_virtfn;
1228}
1229EXPORT_SYMBOL_GPL(pci_sriov_configure_simple);