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path: root/drivers/pci/iov.c
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-rw-r--r--drivers/pci/iov.c680
1 files changed, 680 insertions, 0 deletions
diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
new file mode 100644
index 000000000000..7227efc760db
--- /dev/null
+++ b/drivers/pci/iov.c
@@ -0,0 +1,680 @@
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 */
9
10#include <linux/pci.h>
11#include <linux/mutex.h>
12#include <linux/string.h>
13#include <linux/delay.h>
14#include "pci.h"
15
16#define VIRTFN_ID_LEN 16
17
18static inline u8 virtfn_bus(struct pci_dev *dev, int id)
19{
20 return dev->bus->number + ((dev->devfn + dev->sriov->offset +
21 dev->sriov->stride * id) >> 8);
22}
23
24static inline u8 virtfn_devfn(struct pci_dev *dev, int id)
25{
26 return (dev->devfn + dev->sriov->offset +
27 dev->sriov->stride * id) & 0xff;
28}
29
30static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr)
31{
32 int rc;
33 struct pci_bus *child;
34
35 if (bus->number == busnr)
36 return bus;
37
38 child = pci_find_bus(pci_domain_nr(bus), busnr);
39 if (child)
40 return child;
41
42 child = pci_add_new_bus(bus, NULL, busnr);
43 if (!child)
44 return NULL;
45
46 child->subordinate = busnr;
47 child->dev.parent = bus->bridge;
48 rc = pci_bus_add_child(child);
49 if (rc) {
50 pci_remove_bus(child);
51 return NULL;
52 }
53
54 return child;
55}
56
57static void virtfn_remove_bus(struct pci_bus *bus, int busnr)
58{
59 struct pci_bus *child;
60
61 if (bus->number == busnr)
62 return;
63
64 child = pci_find_bus(pci_domain_nr(bus), busnr);
65 BUG_ON(!child);
66
67 if (list_empty(&child->devices))
68 pci_remove_bus(child);
69}
70
71static int virtfn_add(struct pci_dev *dev, int id, int reset)
72{
73 int i;
74 int rc;
75 u64 size;
76 char buf[VIRTFN_ID_LEN];
77 struct pci_dev *virtfn;
78 struct resource *res;
79 struct pci_sriov *iov = dev->sriov;
80
81 virtfn = alloc_pci_dev();
82 if (!virtfn)
83 return -ENOMEM;
84
85 mutex_lock(&iov->dev->sriov->lock);
86 virtfn->bus = virtfn_add_bus(dev->bus, virtfn_bus(dev, id));
87 if (!virtfn->bus) {
88 kfree(virtfn);
89 mutex_unlock(&iov->dev->sriov->lock);
90 return -ENOMEM;
91 }
92 virtfn->devfn = virtfn_devfn(dev, id);
93 virtfn->vendor = dev->vendor;
94 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_DID, &virtfn->device);
95 pci_setup_device(virtfn);
96 virtfn->dev.parent = dev->dev.parent;
97
98 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
99 res = dev->resource + PCI_IOV_RESOURCES + i;
100 if (!res->parent)
101 continue;
102 virtfn->resource[i].name = pci_name(virtfn);
103 virtfn->resource[i].flags = res->flags;
104 size = resource_size(res);
105 do_div(size, iov->total);
106 virtfn->resource[i].start = res->start + size * id;
107 virtfn->resource[i].end = virtfn->resource[i].start + size - 1;
108 rc = request_resource(res, &virtfn->resource[i]);
109 BUG_ON(rc);
110 }
111
112 if (reset)
113 pci_execute_reset_function(virtfn);
114
115 pci_device_add(virtfn, virtfn->bus);
116 mutex_unlock(&iov->dev->sriov->lock);
117
118 virtfn->physfn = pci_dev_get(dev);
119 virtfn->is_virtfn = 1;
120
121 rc = pci_bus_add_device(virtfn);
122 if (rc)
123 goto failed1;
124 sprintf(buf, "virtfn%u", id);
125 rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
126 if (rc)
127 goto failed1;
128 rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");
129 if (rc)
130 goto failed2;
131
132 kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);
133
134 return 0;
135
136failed2:
137 sysfs_remove_link(&dev->dev.kobj, buf);
138failed1:
139 pci_dev_put(dev);
140 mutex_lock(&iov->dev->sriov->lock);
141 pci_remove_bus_device(virtfn);
142 virtfn_remove_bus(dev->bus, virtfn_bus(dev, id));
143 mutex_unlock(&iov->dev->sriov->lock);
144
145 return rc;
146}
147
148static void virtfn_remove(struct pci_dev *dev, int id, int reset)
149{
150 char buf[VIRTFN_ID_LEN];
151 struct pci_bus *bus;
152 struct pci_dev *virtfn;
153 struct pci_sriov *iov = dev->sriov;
154
155 bus = pci_find_bus(pci_domain_nr(dev->bus), virtfn_bus(dev, id));
156 if (!bus)
157 return;
158
159 virtfn = pci_get_slot(bus, virtfn_devfn(dev, id));
160 if (!virtfn)
161 return;
162
163 pci_dev_put(virtfn);
164
165 if (reset) {
166 device_release_driver(&virtfn->dev);
167 pci_execute_reset_function(virtfn);
168 }
169
170 sprintf(buf, "virtfn%u", id);
171 sysfs_remove_link(&dev->dev.kobj, buf);
172 sysfs_remove_link(&virtfn->dev.kobj, "physfn");
173
174 mutex_lock(&iov->dev->sriov->lock);
175 pci_remove_bus_device(virtfn);
176 virtfn_remove_bus(dev->bus, virtfn_bus(dev, id));
177 mutex_unlock(&iov->dev->sriov->lock);
178
179 pci_dev_put(dev);
180}
181
182static int sriov_migration(struct pci_dev *dev)
183{
184 u16 status;
185 struct pci_sriov *iov = dev->sriov;
186
187 if (!iov->nr_virtfn)
188 return 0;
189
190 if (!(iov->cap & PCI_SRIOV_CAP_VFM))
191 return 0;
192
193 pci_read_config_word(dev, iov->pos + PCI_SRIOV_STATUS, &status);
194 if (!(status & PCI_SRIOV_STATUS_VFM))
195 return 0;
196
197 schedule_work(&iov->mtask);
198
199 return 1;
200}
201
202static void sriov_migration_task(struct work_struct *work)
203{
204 int i;
205 u8 state;
206 u16 status;
207 struct pci_sriov *iov = container_of(work, struct pci_sriov, mtask);
208
209 for (i = iov->initial; i < iov->nr_virtfn; i++) {
210 state = readb(iov->mstate + i);
211 if (state == PCI_SRIOV_VFM_MI) {
212 writeb(PCI_SRIOV_VFM_AV, iov->mstate + i);
213 state = readb(iov->mstate + i);
214 if (state == PCI_SRIOV_VFM_AV)
215 virtfn_add(iov->self, i, 1);
216 } else if (state == PCI_SRIOV_VFM_MO) {
217 virtfn_remove(iov->self, i, 1);
218 writeb(PCI_SRIOV_VFM_UA, iov->mstate + i);
219 state = readb(iov->mstate + i);
220 if (state == PCI_SRIOV_VFM_AV)
221 virtfn_add(iov->self, i, 0);
222 }
223 }
224
225 pci_read_config_word(iov->self, iov->pos + PCI_SRIOV_STATUS, &status);
226 status &= ~PCI_SRIOV_STATUS_VFM;
227 pci_write_config_word(iov->self, iov->pos + PCI_SRIOV_STATUS, status);
228}
229
230static int sriov_enable_migration(struct pci_dev *dev, int nr_virtfn)
231{
232 int bir;
233 u32 table;
234 resource_size_t pa;
235 struct pci_sriov *iov = dev->sriov;
236
237 if (nr_virtfn <= iov->initial)
238 return 0;
239
240 pci_read_config_dword(dev, iov->pos + PCI_SRIOV_VFM, &table);
241 bir = PCI_SRIOV_VFM_BIR(table);
242 if (bir > PCI_STD_RESOURCE_END)
243 return -EIO;
244
245 table = PCI_SRIOV_VFM_OFFSET(table);
246 if (table + nr_virtfn > pci_resource_len(dev, bir))
247 return -EIO;
248
249 pa = pci_resource_start(dev, bir) + table;
250 iov->mstate = ioremap(pa, nr_virtfn);
251 if (!iov->mstate)
252 return -ENOMEM;
253
254 INIT_WORK(&iov->mtask, sriov_migration_task);
255
256 iov->ctrl |= PCI_SRIOV_CTRL_VFM | PCI_SRIOV_CTRL_INTR;
257 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
258
259 return 0;
260}
261
262static void sriov_disable_migration(struct pci_dev *dev)
263{
264 struct pci_sriov *iov = dev->sriov;
265
266 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFM | PCI_SRIOV_CTRL_INTR);
267 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
268
269 cancel_work_sync(&iov->mtask);
270 iounmap(iov->mstate);
271}
272
273static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
274{
275 int rc;
276 int i, j;
277 int nres;
278 u16 offset, stride, initial;
279 struct resource *res;
280 struct pci_dev *pdev;
281 struct pci_sriov *iov = dev->sriov;
282
283 if (!nr_virtfn)
284 return 0;
285
286 if (iov->nr_virtfn)
287 return -EINVAL;
288
289 pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial);
290 if (initial > iov->total ||
291 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total)))
292 return -EIO;
293
294 if (nr_virtfn < 0 || nr_virtfn > iov->total ||
295 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
296 return -EINVAL;
297
298 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn);
299 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &offset);
300 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &stride);
301 if (!offset || (nr_virtfn > 1 && !stride))
302 return -EIO;
303
304 nres = 0;
305 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
306 res = dev->resource + PCI_IOV_RESOURCES + i;
307 if (res->parent)
308 nres++;
309 }
310 if (nres != iov->nres) {
311 dev_err(&dev->dev, "not enough MMIO resources for SR-IOV\n");
312 return -ENOMEM;
313 }
314
315 iov->offset = offset;
316 iov->stride = stride;
317
318 if (virtfn_bus(dev, nr_virtfn - 1) > dev->bus->subordinate) {
319 dev_err(&dev->dev, "SR-IOV: bus number out of range\n");
320 return -ENOMEM;
321 }
322
323 if (iov->link != dev->devfn) {
324 pdev = pci_get_slot(dev->bus, iov->link);
325 if (!pdev)
326 return -ENODEV;
327
328 pci_dev_put(pdev);
329
330 if (!pdev->is_physfn)
331 return -ENODEV;
332
333 rc = sysfs_create_link(&dev->dev.kobj,
334 &pdev->dev.kobj, "dep_link");
335 if (rc)
336 return rc;
337 }
338
339 iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
340 pci_block_user_cfg_access(dev);
341 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
342 msleep(100);
343 pci_unblock_user_cfg_access(dev);
344
345 iov->initial = initial;
346 if (nr_virtfn < initial)
347 initial = nr_virtfn;
348
349 for (i = 0; i < initial; i++) {
350 rc = virtfn_add(dev, i, 0);
351 if (rc)
352 goto failed;
353 }
354
355 if (iov->cap & PCI_SRIOV_CAP_VFM) {
356 rc = sriov_enable_migration(dev, nr_virtfn);
357 if (rc)
358 goto failed;
359 }
360
361 kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE);
362 iov->nr_virtfn = nr_virtfn;
363
364 return 0;
365
366failed:
367 for (j = 0; j < i; j++)
368 virtfn_remove(dev, j, 0);
369
370 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
371 pci_block_user_cfg_access(dev);
372 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
373 ssleep(1);
374 pci_unblock_user_cfg_access(dev);
375
376 if (iov->link != dev->devfn)
377 sysfs_remove_link(&dev->dev.kobj, "dep_link");
378
379 return rc;
380}
381
382static void sriov_disable(struct pci_dev *dev)
383{
384 int i;
385 struct pci_sriov *iov = dev->sriov;
386
387 if (!iov->nr_virtfn)
388 return;
389
390 if (iov->cap & PCI_SRIOV_CAP_VFM)
391 sriov_disable_migration(dev);
392
393 for (i = 0; i < iov->nr_virtfn; i++)
394 virtfn_remove(dev, i, 0);
395
396 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
397 pci_block_user_cfg_access(dev);
398 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
399 ssleep(1);
400 pci_unblock_user_cfg_access(dev);
401
402 if (iov->link != dev->devfn)
403 sysfs_remove_link(&dev->dev.kobj, "dep_link");
404
405 iov->nr_virtfn = 0;
406}
407
408static int sriov_init(struct pci_dev *dev, int pos)
409{
410 int i;
411 int rc;
412 int nres;
413 u32 pgsz;
414 u16 ctrl, total, offset, stride;
415 struct pci_sriov *iov;
416 struct resource *res;
417 struct pci_dev *pdev;
418
419 if (dev->pcie_type != PCI_EXP_TYPE_RC_END &&
420 dev->pcie_type != PCI_EXP_TYPE_ENDPOINT)
421 return -ENODEV;
422
423 pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl);
424 if (ctrl & PCI_SRIOV_CTRL_VFE) {
425 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0);
426 ssleep(1);
427 }
428
429 pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total);
430 if (!total)
431 return 0;
432
433 ctrl = 0;
434 list_for_each_entry(pdev, &dev->bus->devices, bus_list)
435 if (pdev->is_physfn)
436 goto found;
437
438 pdev = NULL;
439 if (pci_ari_enabled(dev->bus))
440 ctrl |= PCI_SRIOV_CTRL_ARI;
441
442found:
443 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl);
444 pci_write_config_word(dev, pos + PCI_SRIOV_NUM_VF, total);
445 pci_read_config_word(dev, pos + PCI_SRIOV_VF_OFFSET, &offset);
446 pci_read_config_word(dev, pos + PCI_SRIOV_VF_STRIDE, &stride);
447 if (!offset || (total > 1 && !stride))
448 return -EIO;
449
450 pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz);
451 i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0;
452 pgsz &= ~((1 << i) - 1);
453 if (!pgsz)
454 return -EIO;
455
456 pgsz &= ~(pgsz - 1);
457 pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz);
458
459 nres = 0;
460 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
461 res = dev->resource + PCI_IOV_RESOURCES + i;
462 i += __pci_read_base(dev, pci_bar_unknown, res,
463 pos + PCI_SRIOV_BAR + i * 4);
464 if (!res->flags)
465 continue;
466 if (resource_size(res) & (PAGE_SIZE - 1)) {
467 rc = -EIO;
468 goto failed;
469 }
470 res->end = res->start + resource_size(res) * total - 1;
471 nres++;
472 }
473
474 iov = kzalloc(sizeof(*iov), GFP_KERNEL);
475 if (!iov) {
476 rc = -ENOMEM;
477 goto failed;
478 }
479
480 iov->pos = pos;
481 iov->nres = nres;
482 iov->ctrl = ctrl;
483 iov->total = total;
484 iov->offset = offset;
485 iov->stride = stride;
486 iov->pgsz = pgsz;
487 iov->self = dev;
488 pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap);
489 pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link);
490
491 if (pdev)
492 iov->dev = pci_dev_get(pdev);
493 else {
494 iov->dev = dev;
495 mutex_init(&iov->lock);
496 }
497
498 dev->sriov = iov;
499 dev->is_physfn = 1;
500
501 return 0;
502
503failed:
504 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
505 res = dev->resource + PCI_IOV_RESOURCES + i;
506 res->flags = 0;
507 }
508
509 return rc;
510}
511
512static void sriov_release(struct pci_dev *dev)
513{
514 BUG_ON(dev->sriov->nr_virtfn);
515
516 if (dev == dev->sriov->dev)
517 mutex_destroy(&dev->sriov->lock);
518 else
519 pci_dev_put(dev->sriov->dev);
520
521 kfree(dev->sriov);
522 dev->sriov = NULL;
523}
524
525static void sriov_restore_state(struct pci_dev *dev)
526{
527 int i;
528 u16 ctrl;
529 struct pci_sriov *iov = dev->sriov;
530
531 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl);
532 if (ctrl & PCI_SRIOV_CTRL_VFE)
533 return;
534
535 for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++)
536 pci_update_resource(dev, i);
537
538 pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
539 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, iov->nr_virtfn);
540 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
541 if (iov->ctrl & PCI_SRIOV_CTRL_VFE)
542 msleep(100);
543}
544
545/**
546 * pci_iov_init - initialize the IOV capability
547 * @dev: the PCI device
548 *
549 * Returns 0 on success, or negative on failure.
550 */
551int pci_iov_init(struct pci_dev *dev)
552{
553 int pos;
554
555 if (!dev->is_pcie)
556 return -ENODEV;
557
558 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV);
559 if (pos)
560 return sriov_init(dev, pos);
561
562 return -ENODEV;
563}
564
565/**
566 * pci_iov_release - release resources used by the IOV capability
567 * @dev: the PCI device
568 */
569void pci_iov_release(struct pci_dev *dev)
570{
571 if (dev->is_physfn)
572 sriov_release(dev);
573}
574
575/**
576 * pci_iov_resource_bar - get position of the SR-IOV BAR
577 * @dev: the PCI device
578 * @resno: the resource number
579 * @type: the BAR type to be filled in
580 *
581 * Returns position of the BAR encapsulated in the SR-IOV capability.
582 */
583int pci_iov_resource_bar(struct pci_dev *dev, int resno,
584 enum pci_bar_type *type)
585{
586 if (resno < PCI_IOV_RESOURCES || resno > PCI_IOV_RESOURCE_END)
587 return 0;
588
589 BUG_ON(!dev->is_physfn);
590
591 *type = pci_bar_unknown;
592
593 return dev->sriov->pos + PCI_SRIOV_BAR +
594 4 * (resno - PCI_IOV_RESOURCES);
595}
596
597/**
598 * pci_restore_iov_state - restore the state of the IOV capability
599 * @dev: the PCI device
600 */
601void pci_restore_iov_state(struct pci_dev *dev)
602{
603 if (dev->is_physfn)
604 sriov_restore_state(dev);
605}
606
607/**
608 * pci_iov_bus_range - find bus range used by Virtual Function
609 * @bus: the PCI bus
610 *
611 * Returns max number of buses (exclude current one) used by Virtual
612 * Functions.
613 */
614int pci_iov_bus_range(struct pci_bus *bus)
615{
616 int max = 0;
617 u8 busnr;
618 struct pci_dev *dev;
619
620 list_for_each_entry(dev, &bus->devices, bus_list) {
621 if (!dev->is_physfn)
622 continue;
623 busnr = virtfn_bus(dev, dev->sriov->total - 1);
624 if (busnr > max)
625 max = busnr;
626 }
627
628 return max ? max - bus->number : 0;
629}
630
631/**
632 * pci_enable_sriov - enable the SR-IOV capability
633 * @dev: the PCI device
634 *
635 * Returns 0 on success, or negative on failure.
636 */
637int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
638{
639 might_sleep();
640
641 if (!dev->is_physfn)
642 return -ENODEV;
643
644 return sriov_enable(dev, nr_virtfn);
645}
646EXPORT_SYMBOL_GPL(pci_enable_sriov);
647
648/**
649 * pci_disable_sriov - disable the SR-IOV capability
650 * @dev: the PCI device
651 */
652void pci_disable_sriov(struct pci_dev *dev)
653{
654 might_sleep();
655
656 if (!dev->is_physfn)
657 return;
658
659 sriov_disable(dev);
660}
661EXPORT_SYMBOL_GPL(pci_disable_sriov);
662
663/**
664 * pci_sriov_migration - notify SR-IOV core of Virtual Function Migration
665 * @dev: the PCI device
666 *
667 * Returns IRQ_HANDLED if the IRQ is handled, or IRQ_NONE if not.
668 *
669 * Physical Function driver is responsible to register IRQ handler using
670 * VF Migration Interrupt Message Number, and call this function when the
671 * interrupt is generated by the hardware.
672 */
673irqreturn_t pci_sriov_migration(struct pci_dev *dev)
674{
675 if (!dev->is_physfn)
676 return IRQ_NONE;
677
678 return sriov_migration(dev) ? IRQ_HANDLED : IRQ_NONE;
679}
680EXPORT_SYMBOL_GPL(pci_sriov_migration);