Commit | Line | Data |
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deb2d2ec | 1 | /* |
c0db9cbc TV |
2 | * vgaarb.c: Implements the VGA arbitration. For details refer to |
3 | * Documentation/vgaarbiter.txt | |
4 | * | |
deb2d2ec BH |
5 | * |
6 | * (C) Copyright 2005 Benjamin Herrenschmidt <benh@kernel.crashing.org> | |
7 | * (C) Copyright 2007 Paulo R. Zanoni <przanoni@gmail.com> | |
8 | * (C) Copyright 2007, 2009 Tiago Vignatti <vignatti@freedesktop.org> | |
9 | * | |
c0db9cbc TV |
10 | * Permission is hereby granted, free of charge, to any person obtaining a |
11 | * copy of this software and associated documentation files (the "Software"), | |
12 | * to deal in the Software without restriction, including without limitation | |
13 | * the rights to use, copy, modify, merge, publish, distribute, sublicense, | |
14 | * and/or sell copies of the Software, and to permit persons to whom the | |
15 | * Software is furnished to do so, subject to the following conditions: | |
16 | * | |
17 | * The above copyright notice and this permission notice (including the next | |
18 | * paragraph) shall be included in all copies or substantial portions of the | |
19 | * Software. | |
20 | * | |
21 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
22 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
23 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
24 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
25 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING | |
26 | * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER | |
27 | * DEALINGS | |
28 | * IN THE SOFTWARE. | |
29 | * | |
deb2d2ec BH |
30 | */ |
31 | ||
32 | #include <linux/module.h> | |
33 | #include <linux/kernel.h> | |
34 | #include <linux/pci.h> | |
35 | #include <linux/errno.h> | |
36 | #include <linux/init.h> | |
37 | #include <linux/list.h> | |
38 | #include <linux/sched.h> | |
39 | #include <linux/wait.h> | |
40 | #include <linux/spinlock.h> | |
41 | #include <linux/poll.h> | |
42 | #include <linux/miscdevice.h> | |
5a0e3ad6 | 43 | #include <linux/slab.h> |
deb2d2ec BH |
44 | |
45 | #include <linux/uaccess.h> | |
46 | ||
47 | #include <linux/vgaarb.h> | |
48 | ||
49 | static void vga_arbiter_notify_clients(void); | |
50 | /* | |
51 | * We keep a list of all vga devices in the system to speed | |
52 | * up the various operations of the arbiter | |
53 | */ | |
54 | struct vga_device { | |
55 | struct list_head list; | |
56 | struct pci_dev *pdev; | |
57 | unsigned int decodes; /* what does it decodes */ | |
58 | unsigned int owns; /* what does it owns */ | |
59 | unsigned int locks; /* what does it locks */ | |
60 | unsigned int io_lock_cnt; /* legacy IO lock count */ | |
61 | unsigned int mem_lock_cnt; /* legacy MEM lock count */ | |
62 | unsigned int io_norm_cnt; /* normal IO count */ | |
63 | unsigned int mem_norm_cnt; /* normal MEM count */ | |
3448a19d | 64 | bool bridge_has_one_vga; |
deb2d2ec BH |
65 | /* allow IRQ enable/disable hook */ |
66 | void *cookie; | |
67 | void (*irq_set_state)(void *cookie, bool enable); | |
68 | unsigned int (*set_vga_decode)(void *cookie, bool decode); | |
69 | }; | |
70 | ||
71 | static LIST_HEAD(vga_list); | |
72 | static int vga_count, vga_decode_count; | |
73 | static bool vga_arbiter_used; | |
74 | static DEFINE_SPINLOCK(vga_lock); | |
75 | static DECLARE_WAIT_QUEUE_HEAD(vga_wait_queue); | |
76 | ||
77 | ||
78 | static const char *vga_iostate_to_str(unsigned int iostate) | |
79 | { | |
80 | /* Ignore VGA_RSRC_IO and VGA_RSRC_MEM */ | |
81 | iostate &= VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
82 | switch (iostate) { | |
83 | case VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM: | |
84 | return "io+mem"; | |
85 | case VGA_RSRC_LEGACY_IO: | |
86 | return "io"; | |
87 | case VGA_RSRC_LEGACY_MEM: | |
88 | return "mem"; | |
89 | } | |
90 | return "none"; | |
91 | } | |
92 | ||
93 | static int vga_str_to_iostate(char *buf, int str_size, int *io_state) | |
94 | { | |
95 | /* we could in theory hand out locks on IO and mem | |
96 | * separately to userspace but it can cause deadlocks */ | |
97 | if (strncmp(buf, "none", 4) == 0) { | |
98 | *io_state = VGA_RSRC_NONE; | |
99 | return 1; | |
100 | } | |
101 | ||
102 | /* XXX We're not chekcing the str_size! */ | |
103 | if (strncmp(buf, "io+mem", 6) == 0) | |
104 | goto both; | |
105 | else if (strncmp(buf, "io", 2) == 0) | |
106 | goto both; | |
107 | else if (strncmp(buf, "mem", 3) == 0) | |
108 | goto both; | |
109 | return 0; | |
110 | both: | |
111 | *io_state = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
112 | return 1; | |
113 | } | |
114 | ||
115 | #ifndef __ARCH_HAS_VGA_DEFAULT_DEVICE | |
116 | /* this is only used a cookie - it should not be dereferenced */ | |
117 | static struct pci_dev *vga_default; | |
118 | #endif | |
119 | ||
120 | static void vga_arb_device_card_gone(struct pci_dev *pdev); | |
121 | ||
122 | /* Find somebody in our list */ | |
123 | static struct vga_device *vgadev_find(struct pci_dev *pdev) | |
124 | { | |
125 | struct vga_device *vgadev; | |
126 | ||
127 | list_for_each_entry(vgadev, &vga_list, list) | |
128 | if (pdev == vgadev->pdev) | |
129 | return vgadev; | |
130 | return NULL; | |
131 | } | |
132 | ||
133 | /* Returns the default VGA device (vgacon's babe) */ | |
134 | #ifndef __ARCH_HAS_VGA_DEFAULT_DEVICE | |
135 | struct pci_dev *vga_default_device(void) | |
136 | { | |
137 | return vga_default; | |
138 | } | |
1a39b310 | 139 | |
1b23170a MG |
140 | EXPORT_SYMBOL_GPL(vga_default_device); |
141 | ||
1a39b310 MG |
142 | void vga_set_default_device(struct pci_dev *pdev) |
143 | { | |
84544a1d YL |
144 | if (vga_default == pdev) |
145 | return; | |
146 | ||
147 | pci_dev_put(vga_default); | |
148 | vga_default = pci_dev_get(pdev); | |
1a39b310 | 149 | } |
deb2d2ec BH |
150 | #endif |
151 | ||
152 | static inline void vga_irq_set_state(struct vga_device *vgadev, bool state) | |
153 | { | |
154 | if (vgadev->irq_set_state) | |
155 | vgadev->irq_set_state(vgadev->cookie, state); | |
156 | } | |
157 | ||
158 | ||
159 | /* If we don't ever use VGA arb we should avoid | |
160 | turning off anything anywhere due to old X servers getting | |
161 | confused about the boot device not being VGA */ | |
162 | static void vga_check_first_use(void) | |
163 | { | |
164 | /* we should inform all GPUs in the system that | |
25985edc | 165 | * VGA arb has occurred and to try and disable resources |
deb2d2ec BH |
166 | * if they can */ |
167 | if (!vga_arbiter_used) { | |
168 | vga_arbiter_used = true; | |
169 | vga_arbiter_notify_clients(); | |
170 | } | |
171 | } | |
172 | ||
173 | static struct vga_device *__vga_tryget(struct vga_device *vgadev, | |
174 | unsigned int rsrc) | |
175 | { | |
176 | unsigned int wants, legacy_wants, match; | |
177 | struct vga_device *conflict; | |
178 | unsigned int pci_bits; | |
3448a19d DA |
179 | u32 flags = 0; |
180 | ||
deb2d2ec BH |
181 | /* Account for "normal" resources to lock. If we decode the legacy, |
182 | * counterpart, we need to request it as well | |
183 | */ | |
184 | if ((rsrc & VGA_RSRC_NORMAL_IO) && | |
185 | (vgadev->decodes & VGA_RSRC_LEGACY_IO)) | |
186 | rsrc |= VGA_RSRC_LEGACY_IO; | |
187 | if ((rsrc & VGA_RSRC_NORMAL_MEM) && | |
188 | (vgadev->decodes & VGA_RSRC_LEGACY_MEM)) | |
189 | rsrc |= VGA_RSRC_LEGACY_MEM; | |
190 | ||
2d6e9b91 TV |
191 | pr_debug("%s: %d\n", __func__, rsrc); |
192 | pr_debug("%s: owns: %d\n", __func__, vgadev->owns); | |
deb2d2ec BH |
193 | |
194 | /* Check what resources we need to acquire */ | |
195 | wants = rsrc & ~vgadev->owns; | |
196 | ||
197 | /* We already own everything, just mark locked & bye bye */ | |
198 | if (wants == 0) | |
199 | goto lock_them; | |
200 | ||
201 | /* We don't need to request a legacy resource, we just enable | |
202 | * appropriate decoding and go | |
203 | */ | |
204 | legacy_wants = wants & VGA_RSRC_LEGACY_MASK; | |
205 | if (legacy_wants == 0) | |
206 | goto enable_them; | |
207 | ||
208 | /* Ok, we don't, let's find out how we need to kick off */ | |
209 | list_for_each_entry(conflict, &vga_list, list) { | |
210 | unsigned int lwants = legacy_wants; | |
211 | unsigned int change_bridge = 0; | |
212 | ||
213 | /* Don't conflict with myself */ | |
214 | if (vgadev == conflict) | |
215 | continue; | |
216 | ||
217 | /* Check if the architecture allows a conflict between those | |
218 | * 2 devices or if they are on separate domains | |
219 | */ | |
220 | if (!vga_conflicts(vgadev->pdev, conflict->pdev)) | |
221 | continue; | |
222 | ||
223 | /* We have a possible conflict. before we go further, we must | |
224 | * check if we sit on the same bus as the conflicting device. | |
225 | * if we don't, then we must tie both IO and MEM resources | |
226 | * together since there is only a single bit controlling | |
227 | * VGA forwarding on P2P bridges | |
228 | */ | |
229 | if (vgadev->pdev->bus != conflict->pdev->bus) { | |
230 | change_bridge = 1; | |
231 | lwants = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
232 | } | |
233 | ||
234 | /* Check if the guy has a lock on the resource. If he does, | |
235 | * return the conflicting entry | |
236 | */ | |
237 | if (conflict->locks & lwants) | |
238 | return conflict; | |
239 | ||
240 | /* Ok, now check if he owns the resource we want. We don't need | |
241 | * to check "decodes" since it should be impossible to own | |
242 | * own legacy resources you don't decode unless I have a bug | |
243 | * in this code... | |
244 | */ | |
245 | WARN_ON(conflict->owns & ~conflict->decodes); | |
246 | match = lwants & conflict->owns; | |
247 | if (!match) | |
248 | continue; | |
249 | ||
250 | /* looks like he doesn't have a lock, we can steal | |
251 | * them from him | |
252 | */ | |
deb2d2ec | 253 | |
3448a19d | 254 | flags = 0; |
deb2d2ec | 255 | pci_bits = 0; |
deb2d2ec | 256 | |
3448a19d DA |
257 | if (!conflict->bridge_has_one_vga) { |
258 | vga_irq_set_state(conflict, false); | |
259 | flags |= PCI_VGA_STATE_CHANGE_DECODES; | |
260 | if (lwants & (VGA_RSRC_LEGACY_MEM|VGA_RSRC_NORMAL_MEM)) | |
261 | pci_bits |= PCI_COMMAND_MEMORY; | |
262 | if (lwants & (VGA_RSRC_LEGACY_IO|VGA_RSRC_NORMAL_IO)) | |
263 | pci_bits |= PCI_COMMAND_IO; | |
264 | } | |
265 | ||
266 | if (change_bridge) | |
267 | flags |= PCI_VGA_STATE_CHANGE_BRIDGE; | |
268 | ||
269 | pci_set_vga_state(conflict->pdev, false, pci_bits, flags); | |
deb2d2ec BH |
270 | conflict->owns &= ~lwants; |
271 | /* If he also owned non-legacy, that is no longer the case */ | |
272 | if (lwants & VGA_RSRC_LEGACY_MEM) | |
273 | conflict->owns &= ~VGA_RSRC_NORMAL_MEM; | |
274 | if (lwants & VGA_RSRC_LEGACY_IO) | |
275 | conflict->owns &= ~VGA_RSRC_NORMAL_IO; | |
276 | } | |
277 | ||
278 | enable_them: | |
279 | /* ok dude, we got it, everybody conflicting has been disabled, let's | |
280 | * enable us. Make sure we don't mark a bit in "owns" that we don't | |
281 | * also have in "decodes". We can lock resources we don't decode but | |
282 | * not own them. | |
283 | */ | |
3448a19d | 284 | flags = 0; |
deb2d2ec | 285 | pci_bits = 0; |
deb2d2ec | 286 | |
3448a19d DA |
287 | if (!vgadev->bridge_has_one_vga) { |
288 | flags |= PCI_VGA_STATE_CHANGE_DECODES; | |
289 | if (wants & (VGA_RSRC_LEGACY_MEM|VGA_RSRC_NORMAL_MEM)) | |
290 | pci_bits |= PCI_COMMAND_MEMORY; | |
291 | if (wants & (VGA_RSRC_LEGACY_IO|VGA_RSRC_NORMAL_IO)) | |
292 | pci_bits |= PCI_COMMAND_IO; | |
293 | } | |
294 | if (!!(wants & VGA_RSRC_LEGACY_MASK)) | |
295 | flags |= PCI_VGA_STATE_CHANGE_BRIDGE; | |
296 | ||
297 | pci_set_vga_state(vgadev->pdev, true, pci_bits, flags); | |
298 | ||
299 | if (!vgadev->bridge_has_one_vga) { | |
300 | vga_irq_set_state(vgadev, true); | |
301 | } | |
deb2d2ec BH |
302 | vgadev->owns |= (wants & vgadev->decodes); |
303 | lock_them: | |
304 | vgadev->locks |= (rsrc & VGA_RSRC_LEGACY_MASK); | |
305 | if (rsrc & VGA_RSRC_LEGACY_IO) | |
306 | vgadev->io_lock_cnt++; | |
307 | if (rsrc & VGA_RSRC_LEGACY_MEM) | |
308 | vgadev->mem_lock_cnt++; | |
309 | if (rsrc & VGA_RSRC_NORMAL_IO) | |
310 | vgadev->io_norm_cnt++; | |
311 | if (rsrc & VGA_RSRC_NORMAL_MEM) | |
312 | vgadev->mem_norm_cnt++; | |
313 | ||
314 | return NULL; | |
315 | } | |
316 | ||
317 | static void __vga_put(struct vga_device *vgadev, unsigned int rsrc) | |
318 | { | |
319 | unsigned int old_locks = vgadev->locks; | |
320 | ||
2d6e9b91 | 321 | pr_debug("%s\n", __func__); |
deb2d2ec BH |
322 | |
323 | /* Update our counters, and account for equivalent legacy resources | |
324 | * if we decode them | |
325 | */ | |
326 | if ((rsrc & VGA_RSRC_NORMAL_IO) && vgadev->io_norm_cnt > 0) { | |
327 | vgadev->io_norm_cnt--; | |
328 | if (vgadev->decodes & VGA_RSRC_LEGACY_IO) | |
329 | rsrc |= VGA_RSRC_LEGACY_IO; | |
330 | } | |
331 | if ((rsrc & VGA_RSRC_NORMAL_MEM) && vgadev->mem_norm_cnt > 0) { | |
332 | vgadev->mem_norm_cnt--; | |
333 | if (vgadev->decodes & VGA_RSRC_LEGACY_MEM) | |
334 | rsrc |= VGA_RSRC_LEGACY_MEM; | |
335 | } | |
336 | if ((rsrc & VGA_RSRC_LEGACY_IO) && vgadev->io_lock_cnt > 0) | |
337 | vgadev->io_lock_cnt--; | |
338 | if ((rsrc & VGA_RSRC_LEGACY_MEM) && vgadev->mem_lock_cnt > 0) | |
339 | vgadev->mem_lock_cnt--; | |
340 | ||
341 | /* Just clear lock bits, we do lazy operations so we don't really | |
342 | * have to bother about anything else at this point | |
343 | */ | |
344 | if (vgadev->io_lock_cnt == 0) | |
345 | vgadev->locks &= ~VGA_RSRC_LEGACY_IO; | |
346 | if (vgadev->mem_lock_cnt == 0) | |
347 | vgadev->locks &= ~VGA_RSRC_LEGACY_MEM; | |
348 | ||
349 | /* Kick the wait queue in case somebody was waiting if we actually | |
350 | * released something | |
351 | */ | |
352 | if (old_locks != vgadev->locks) | |
353 | wake_up_all(&vga_wait_queue); | |
354 | } | |
355 | ||
356 | int vga_get(struct pci_dev *pdev, unsigned int rsrc, int interruptible) | |
357 | { | |
358 | struct vga_device *vgadev, *conflict; | |
359 | unsigned long flags; | |
360 | wait_queue_t wait; | |
361 | int rc = 0; | |
362 | ||
363 | vga_check_first_use(); | |
364 | /* The one who calls us should check for this, but lets be sure... */ | |
365 | if (pdev == NULL) | |
366 | pdev = vga_default_device(); | |
367 | if (pdev == NULL) | |
368 | return 0; | |
369 | ||
370 | for (;;) { | |
371 | spin_lock_irqsave(&vga_lock, flags); | |
372 | vgadev = vgadev_find(pdev); | |
373 | if (vgadev == NULL) { | |
374 | spin_unlock_irqrestore(&vga_lock, flags); | |
375 | rc = -ENODEV; | |
376 | break; | |
377 | } | |
378 | conflict = __vga_tryget(vgadev, rsrc); | |
379 | spin_unlock_irqrestore(&vga_lock, flags); | |
380 | if (conflict == NULL) | |
381 | break; | |
382 | ||
383 | ||
384 | /* We have a conflict, we wait until somebody kicks the | |
385 | * work queue. Currently we have one work queue that we | |
386 | * kick each time some resources are released, but it would | |
387 | * be fairly easy to have a per device one so that we only | |
388 | * need to attach to the conflicting device | |
389 | */ | |
390 | init_waitqueue_entry(&wait, current); | |
391 | add_wait_queue(&vga_wait_queue, &wait); | |
392 | set_current_state(interruptible ? | |
393 | TASK_INTERRUPTIBLE : | |
394 | TASK_UNINTERRUPTIBLE); | |
395 | if (signal_pending(current)) { | |
396 | rc = -EINTR; | |
397 | break; | |
398 | } | |
399 | schedule(); | |
400 | remove_wait_queue(&vga_wait_queue, &wait); | |
401 | set_current_state(TASK_RUNNING); | |
402 | } | |
403 | return rc; | |
404 | } | |
405 | EXPORT_SYMBOL(vga_get); | |
406 | ||
407 | int vga_tryget(struct pci_dev *pdev, unsigned int rsrc) | |
408 | { | |
409 | struct vga_device *vgadev; | |
410 | unsigned long flags; | |
411 | int rc = 0; | |
412 | ||
413 | vga_check_first_use(); | |
414 | ||
415 | /* The one who calls us should check for this, but lets be sure... */ | |
416 | if (pdev == NULL) | |
417 | pdev = vga_default_device(); | |
418 | if (pdev == NULL) | |
419 | return 0; | |
420 | spin_lock_irqsave(&vga_lock, flags); | |
421 | vgadev = vgadev_find(pdev); | |
422 | if (vgadev == NULL) { | |
423 | rc = -ENODEV; | |
424 | goto bail; | |
425 | } | |
426 | if (__vga_tryget(vgadev, rsrc)) | |
427 | rc = -EBUSY; | |
428 | bail: | |
429 | spin_unlock_irqrestore(&vga_lock, flags); | |
430 | return rc; | |
431 | } | |
432 | EXPORT_SYMBOL(vga_tryget); | |
433 | ||
434 | void vga_put(struct pci_dev *pdev, unsigned int rsrc) | |
435 | { | |
436 | struct vga_device *vgadev; | |
437 | unsigned long flags; | |
438 | ||
439 | /* The one who calls us should check for this, but lets be sure... */ | |
440 | if (pdev == NULL) | |
441 | pdev = vga_default_device(); | |
442 | if (pdev == NULL) | |
443 | return; | |
444 | spin_lock_irqsave(&vga_lock, flags); | |
445 | vgadev = vgadev_find(pdev); | |
446 | if (vgadev == NULL) | |
447 | goto bail; | |
448 | __vga_put(vgadev, rsrc); | |
449 | bail: | |
450 | spin_unlock_irqrestore(&vga_lock, flags); | |
451 | } | |
452 | EXPORT_SYMBOL(vga_put); | |
453 | ||
3448a19d DA |
454 | /* Rules for using a bridge to control a VGA descendant decoding: |
455 | if a bridge has only one VGA descendant then it can be used | |
456 | to control the VGA routing for that device. | |
457 | It should always use the bridge closest to the device to control it. | |
458 | If a bridge has a direct VGA descendant, but also have a sub-bridge | |
459 | VGA descendant then we cannot use that bridge to control the direct VGA descendant. | |
460 | So for every device we register, we need to iterate all its parent bridges | |
461 | so we can invalidate any devices using them properly. | |
462 | */ | |
463 | static void vga_arbiter_check_bridge_sharing(struct vga_device *vgadev) | |
464 | { | |
465 | struct vga_device *same_bridge_vgadev; | |
466 | struct pci_bus *new_bus, *bus; | |
467 | struct pci_dev *new_bridge, *bridge; | |
468 | ||
469 | vgadev->bridge_has_one_vga = true; | |
470 | ||
471 | if (list_empty(&vga_list)) | |
472 | return; | |
473 | ||
474 | /* okay iterate the new devices bridge hierarachy */ | |
475 | new_bus = vgadev->pdev->bus; | |
476 | while (new_bus) { | |
477 | new_bridge = new_bus->self; | |
478 | ||
f6252114 DA |
479 | /* go through list of devices already registered */ |
480 | list_for_each_entry(same_bridge_vgadev, &vga_list, list) { | |
481 | bus = same_bridge_vgadev->pdev->bus; | |
482 | bridge = bus->self; | |
483 | ||
484 | /* see if the share a bridge with this device */ | |
485 | if (new_bridge == bridge) { | |
486 | /* if their direct parent bridge is the same | |
487 | as any bridge of this device then it can't be used | |
488 | for that device */ | |
489 | same_bridge_vgadev->bridge_has_one_vga = false; | |
490 | } | |
3448a19d | 491 | |
f6252114 DA |
492 | /* now iterate the previous devices bridge hierarchy */ |
493 | /* if the new devices parent bridge is in the other devices | |
494 | hierarchy then we can't use it to control this device */ | |
495 | while (bus) { | |
496 | bridge = bus->self; | |
497 | if (bridge) { | |
498 | if (bridge == vgadev->pdev->bus->self) | |
499 | vgadev->bridge_has_one_vga = false; | |
3448a19d | 500 | } |
f6252114 | 501 | bus = bus->parent; |
3448a19d DA |
502 | } |
503 | } | |
504 | new_bus = new_bus->parent; | |
505 | } | |
506 | } | |
507 | ||
deb2d2ec BH |
508 | /* |
509 | * Currently, we assume that the "initial" setup of the system is | |
510 | * not sane, that is we come up with conflicting devices and let | |
511 | * the arbiter's client decides if devices decodes or not legacy | |
512 | * things. | |
513 | */ | |
514 | static bool vga_arbiter_add_pci_device(struct pci_dev *pdev) | |
515 | { | |
516 | struct vga_device *vgadev; | |
517 | unsigned long flags; | |
518 | struct pci_bus *bus; | |
519 | struct pci_dev *bridge; | |
520 | u16 cmd; | |
521 | ||
522 | /* Only deal with VGA class devices */ | |
523 | if ((pdev->class >> 8) != PCI_CLASS_DISPLAY_VGA) | |
524 | return false; | |
525 | ||
526 | /* Allocate structure */ | |
527 | vgadev = kmalloc(sizeof(struct vga_device), GFP_KERNEL); | |
528 | if (vgadev == NULL) { | |
529 | pr_err("vgaarb: failed to allocate pci device\n"); | |
530 | /* What to do on allocation failure ? For now, let's | |
531 | * just do nothing, I'm not sure there is anything saner | |
532 | * to be done | |
533 | */ | |
534 | return false; | |
535 | } | |
536 | ||
537 | memset(vgadev, 0, sizeof(*vgadev)); | |
538 | ||
539 | /* Take lock & check for duplicates */ | |
540 | spin_lock_irqsave(&vga_lock, flags); | |
541 | if (vgadev_find(pdev) != NULL) { | |
542 | BUG_ON(1); | |
543 | goto fail; | |
544 | } | |
545 | vgadev->pdev = pdev; | |
546 | ||
547 | /* By default, assume we decode everything */ | |
548 | vgadev->decodes = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM | | |
549 | VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM; | |
550 | ||
551 | /* by default mark it as decoding */ | |
552 | vga_decode_count++; | |
553 | /* Mark that we "own" resources based on our enables, we will | |
554 | * clear that below if the bridge isn't forwarding | |
555 | */ | |
556 | pci_read_config_word(pdev, PCI_COMMAND, &cmd); | |
557 | if (cmd & PCI_COMMAND_IO) | |
558 | vgadev->owns |= VGA_RSRC_LEGACY_IO; | |
559 | if (cmd & PCI_COMMAND_MEMORY) | |
560 | vgadev->owns |= VGA_RSRC_LEGACY_MEM; | |
561 | ||
562 | /* Check if VGA cycles can get down to us */ | |
563 | bus = pdev->bus; | |
564 | while (bus) { | |
565 | bridge = bus->self; | |
566 | if (bridge) { | |
567 | u16 l; | |
568 | pci_read_config_word(bridge, PCI_BRIDGE_CONTROL, | |
569 | &l); | |
570 | if (!(l & PCI_BRIDGE_CTL_VGA)) { | |
571 | vgadev->owns = 0; | |
572 | break; | |
573 | } | |
574 | } | |
575 | bus = bus->parent; | |
576 | } | |
577 | ||
578 | /* Deal with VGA default device. Use first enabled one | |
579 | * by default if arch doesn't have it's own hook | |
580 | */ | |
581 | #ifndef __ARCH_HAS_VGA_DEFAULT_DEVICE | |
582 | if (vga_default == NULL && | |
583 | ((vgadev->owns & VGA_RSRC_LEGACY_MASK) == VGA_RSRC_LEGACY_MASK)) | |
84544a1d | 584 | vga_set_default_device(pdev); |
deb2d2ec BH |
585 | #endif |
586 | ||
3448a19d DA |
587 | vga_arbiter_check_bridge_sharing(vgadev); |
588 | ||
deb2d2ec BH |
589 | /* Add to the list */ |
590 | list_add(&vgadev->list, &vga_list); | |
591 | vga_count++; | |
592 | pr_info("vgaarb: device added: PCI:%s,decodes=%s,owns=%s,locks=%s\n", | |
593 | pci_name(pdev), | |
594 | vga_iostate_to_str(vgadev->decodes), | |
595 | vga_iostate_to_str(vgadev->owns), | |
596 | vga_iostate_to_str(vgadev->locks)); | |
597 | ||
598 | spin_unlock_irqrestore(&vga_lock, flags); | |
599 | return true; | |
600 | fail: | |
601 | spin_unlock_irqrestore(&vga_lock, flags); | |
602 | kfree(vgadev); | |
603 | return false; | |
604 | } | |
605 | ||
606 | static bool vga_arbiter_del_pci_device(struct pci_dev *pdev) | |
607 | { | |
608 | struct vga_device *vgadev; | |
609 | unsigned long flags; | |
610 | bool ret = true; | |
611 | ||
612 | spin_lock_irqsave(&vga_lock, flags); | |
613 | vgadev = vgadev_find(pdev); | |
614 | if (vgadev == NULL) { | |
615 | ret = false; | |
616 | goto bail; | |
617 | } | |
618 | ||
1a39b310 | 619 | #ifndef __ARCH_HAS_VGA_DEFAULT_DEVICE |
84544a1d YL |
620 | if (vga_default == pdev) |
621 | vga_set_default_device(NULL); | |
1a39b310 | 622 | #endif |
deb2d2ec BH |
623 | |
624 | if (vgadev->decodes & (VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM)) | |
625 | vga_decode_count--; | |
626 | ||
627 | /* Remove entry from list */ | |
628 | list_del(&vgadev->list); | |
629 | vga_count--; | |
630 | /* Notify userland driver that the device is gone so it discards | |
631 | * it's copies of the pci_dev pointer | |
632 | */ | |
633 | vga_arb_device_card_gone(pdev); | |
634 | ||
635 | /* Wake up all possible waiters */ | |
636 | wake_up_all(&vga_wait_queue); | |
637 | bail: | |
638 | spin_unlock_irqrestore(&vga_lock, flags); | |
639 | kfree(vgadev); | |
640 | return ret; | |
641 | } | |
642 | ||
643 | /* this is called with the lock */ | |
644 | static inline void vga_update_device_decodes(struct vga_device *vgadev, | |
645 | int new_decodes) | |
646 | { | |
647 | int old_decodes; | |
648 | struct vga_device *new_vgadev, *conflict; | |
649 | ||
650 | old_decodes = vgadev->decodes; | |
651 | vgadev->decodes = new_decodes; | |
652 | ||
653 | pr_info("vgaarb: device changed decodes: PCI:%s,olddecodes=%s,decodes=%s:owns=%s\n", | |
654 | pci_name(vgadev->pdev), | |
655 | vga_iostate_to_str(old_decodes), | |
656 | vga_iostate_to_str(vgadev->decodes), | |
657 | vga_iostate_to_str(vgadev->owns)); | |
658 | ||
659 | ||
660 | /* if we own the decodes we should move them along to | |
661 | another card */ | |
662 | if ((vgadev->owns & old_decodes) && (vga_count > 1)) { | |
663 | /* set us to own nothing */ | |
664 | vgadev->owns &= ~old_decodes; | |
665 | list_for_each_entry(new_vgadev, &vga_list, list) { | |
666 | if ((new_vgadev != vgadev) && | |
667 | (new_vgadev->decodes & VGA_RSRC_LEGACY_MASK)) { | |
668 | pr_info("vgaarb: transferring owner from PCI:%s to PCI:%s\n", pci_name(vgadev->pdev), pci_name(new_vgadev->pdev)); | |
669 | conflict = __vga_tryget(new_vgadev, VGA_RSRC_LEGACY_MASK); | |
670 | if (!conflict) | |
671 | __vga_put(new_vgadev, VGA_RSRC_LEGACY_MASK); | |
672 | break; | |
673 | } | |
674 | } | |
675 | } | |
676 | ||
677 | /* change decodes counter */ | |
678 | if (old_decodes != new_decodes) { | |
679 | if (new_decodes & (VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM)) | |
680 | vga_decode_count++; | |
681 | else | |
682 | vga_decode_count--; | |
683 | } | |
2d6e9b91 | 684 | pr_debug("vgaarb: decoding count now is: %d\n", vga_decode_count); |
deb2d2ec BH |
685 | } |
686 | ||
201ba4c4 | 687 | static void __vga_set_legacy_decoding(struct pci_dev *pdev, unsigned int decodes, bool userspace) |
deb2d2ec BH |
688 | { |
689 | struct vga_device *vgadev; | |
690 | unsigned long flags; | |
691 | ||
692 | decodes &= VGA_RSRC_LEGACY_MASK; | |
693 | ||
694 | spin_lock_irqsave(&vga_lock, flags); | |
695 | vgadev = vgadev_find(pdev); | |
696 | if (vgadev == NULL) | |
697 | goto bail; | |
698 | ||
699 | /* don't let userspace futz with kernel driver decodes */ | |
700 | if (userspace && vgadev->set_vga_decode) | |
701 | goto bail; | |
702 | ||
703 | /* update the device decodes + counter */ | |
704 | vga_update_device_decodes(vgadev, decodes); | |
705 | ||
706 | /* XXX if somebody is going from "doesn't decode" to "decodes" state | |
707 | * here, additional care must be taken as we may have pending owner | |
708 | * ship of non-legacy region ... | |
709 | */ | |
710 | bail: | |
711 | spin_unlock_irqrestore(&vga_lock, flags); | |
712 | } | |
713 | ||
714 | void vga_set_legacy_decoding(struct pci_dev *pdev, unsigned int decodes) | |
715 | { | |
716 | __vga_set_legacy_decoding(pdev, decodes, false); | |
717 | } | |
718 | EXPORT_SYMBOL(vga_set_legacy_decoding); | |
719 | ||
deb2d2ec BH |
720 | /* call with NULL to unregister */ |
721 | int vga_client_register(struct pci_dev *pdev, void *cookie, | |
722 | void (*irq_set_state)(void *cookie, bool state), | |
723 | unsigned int (*set_vga_decode)(void *cookie, bool decode)) | |
724 | { | |
934f992c | 725 | int ret = -ENODEV; |
deb2d2ec BH |
726 | struct vga_device *vgadev; |
727 | unsigned long flags; | |
728 | ||
729 | spin_lock_irqsave(&vga_lock, flags); | |
730 | vgadev = vgadev_find(pdev); | |
731 | if (!vgadev) | |
732 | goto bail; | |
733 | ||
734 | vgadev->irq_set_state = irq_set_state; | |
735 | vgadev->set_vga_decode = set_vga_decode; | |
736 | vgadev->cookie = cookie; | |
737 | ret = 0; | |
738 | ||
739 | bail: | |
740 | spin_unlock_irqrestore(&vga_lock, flags); | |
741 | return ret; | |
742 | ||
743 | } | |
744 | EXPORT_SYMBOL(vga_client_register); | |
745 | ||
746 | /* | |
747 | * Char driver implementation | |
748 | * | |
749 | * Semantics is: | |
750 | * | |
751 | * open : open user instance of the arbitrer. by default, it's | |
752 | * attached to the default VGA device of the system. | |
753 | * | |
754 | * close : close user instance, release locks | |
755 | * | |
756 | * read : return a string indicating the status of the target. | |
757 | * an IO state string is of the form {io,mem,io+mem,none}, | |
758 | * mc and ic are respectively mem and io lock counts (for | |
759 | * debugging/diagnostic only). "decodes" indicate what the | |
760 | * card currently decodes, "owns" indicates what is currently | |
761 | * enabled on it, and "locks" indicates what is locked by this | |
762 | * card. If the card is unplugged, we get "invalid" then for | |
763 | * card_ID and an -ENODEV error is returned for any command | |
764 | * until a new card is targeted | |
765 | * | |
766 | * "<card_ID>,decodes=<io_state>,owns=<io_state>,locks=<io_state> (ic,mc)" | |
767 | * | |
768 | * write : write a command to the arbiter. List of commands is: | |
769 | * | |
770 | * target <card_ID> : switch target to card <card_ID> (see below) | |
771 | * lock <io_state> : acquires locks on target ("none" is invalid io_state) | |
772 | * trylock <io_state> : non-blocking acquire locks on target | |
773 | * unlock <io_state> : release locks on target | |
774 | * unlock all : release all locks on target held by this user | |
775 | * decodes <io_state> : set the legacy decoding attributes for the card | |
776 | * | |
777 | * poll : event if something change on any card (not just the target) | |
778 | * | |
779 | * card_ID is of the form "PCI:domain:bus:dev.fn". It can be set to "default" | |
780 | * to go back to the system default card (TODO: not implemented yet). | |
781 | * Currently, only PCI is supported as a prefix, but the userland API may | |
782 | * support other bus types in the future, even if the current kernel | |
783 | * implementation doesn't. | |
784 | * | |
785 | * Note about locks: | |
786 | * | |
787 | * The driver keeps track of which user has what locks on which card. It | |
788 | * supports stacking, like the kernel one. This complexifies the implementation | |
789 | * a bit, but makes the arbiter more tolerant to userspace problems and able | |
790 | * to properly cleanup in all cases when a process dies. | |
791 | * Currently, a max of 16 cards simultaneously can have locks issued from | |
792 | * userspace for a given user (file descriptor instance) of the arbiter. | |
793 | * | |
794 | * If the device is hot-unplugged, there is a hook inside the module to notify | |
795 | * they being added/removed in the system and automatically added/removed in | |
796 | * the arbiter. | |
797 | */ | |
798 | ||
36028f33 | 799 | #define MAX_USER_CARDS CONFIG_VGA_ARB_MAX_GPUS |
deb2d2ec BH |
800 | #define PCI_INVALID_CARD ((struct pci_dev *)-1UL) |
801 | ||
802 | /* | |
803 | * Each user has an array of these, tracking which cards have locks | |
804 | */ | |
805 | struct vga_arb_user_card { | |
806 | struct pci_dev *pdev; | |
807 | unsigned int mem_cnt; | |
808 | unsigned int io_cnt; | |
809 | }; | |
810 | ||
811 | struct vga_arb_private { | |
812 | struct list_head list; | |
813 | struct pci_dev *target; | |
814 | struct vga_arb_user_card cards[MAX_USER_CARDS]; | |
815 | spinlock_t lock; | |
816 | }; | |
817 | ||
818 | static LIST_HEAD(vga_user_list); | |
819 | static DEFINE_SPINLOCK(vga_user_lock); | |
820 | ||
821 | ||
822 | /* | |
823 | * This function gets a string in the format: "PCI:domain:bus:dev.fn" and | |
824 | * returns the respective values. If the string is not in this format, | |
825 | * it returns 0. | |
826 | */ | |
827 | static int vga_pci_str_to_vars(char *buf, int count, unsigned int *domain, | |
828 | unsigned int *bus, unsigned int *devfn) | |
829 | { | |
830 | int n; | |
831 | unsigned int slot, func; | |
832 | ||
833 | ||
834 | n = sscanf(buf, "PCI:%x:%x:%x.%x", domain, bus, &slot, &func); | |
835 | if (n != 4) | |
836 | return 0; | |
837 | ||
838 | *devfn = PCI_DEVFN(slot, func); | |
839 | ||
840 | return 1; | |
841 | } | |
842 | ||
843 | static ssize_t vga_arb_read(struct file *file, char __user * buf, | |
844 | size_t count, loff_t *ppos) | |
845 | { | |
846 | struct vga_arb_private *priv = file->private_data; | |
847 | struct vga_device *vgadev; | |
848 | struct pci_dev *pdev; | |
849 | unsigned long flags; | |
850 | size_t len; | |
851 | int rc; | |
852 | char *lbuf; | |
853 | ||
854 | lbuf = kmalloc(1024, GFP_KERNEL); | |
855 | if (lbuf == NULL) | |
856 | return -ENOMEM; | |
857 | ||
858 | /* Shields against vga_arb_device_card_gone (pci_dev going | |
859 | * away), and allows access to vga list | |
860 | */ | |
861 | spin_lock_irqsave(&vga_lock, flags); | |
862 | ||
25985edc | 863 | /* If we are targeting the default, use it */ |
deb2d2ec BH |
864 | pdev = priv->target; |
865 | if (pdev == NULL || pdev == PCI_INVALID_CARD) { | |
866 | spin_unlock_irqrestore(&vga_lock, flags); | |
867 | len = sprintf(lbuf, "invalid"); | |
868 | goto done; | |
869 | } | |
870 | ||
871 | /* Find card vgadev structure */ | |
872 | vgadev = vgadev_find(pdev); | |
873 | if (vgadev == NULL) { | |
874 | /* Wow, it's not in the list, that shouldn't happen, | |
875 | * let's fix us up and return invalid card | |
876 | */ | |
877 | if (pdev == priv->target) | |
878 | vga_arb_device_card_gone(pdev); | |
879 | spin_unlock_irqrestore(&vga_lock, flags); | |
880 | len = sprintf(lbuf, "invalid"); | |
881 | goto done; | |
882 | } | |
883 | ||
884 | /* Fill the buffer with infos */ | |
885 | len = snprintf(lbuf, 1024, | |
886 | "count:%d,PCI:%s,decodes=%s,owns=%s,locks=%s(%d:%d)\n", | |
887 | vga_decode_count, pci_name(pdev), | |
888 | vga_iostate_to_str(vgadev->decodes), | |
889 | vga_iostate_to_str(vgadev->owns), | |
890 | vga_iostate_to_str(vgadev->locks), | |
891 | vgadev->io_lock_cnt, vgadev->mem_lock_cnt); | |
892 | ||
893 | spin_unlock_irqrestore(&vga_lock, flags); | |
894 | done: | |
895 | ||
896 | /* Copy that to user */ | |
897 | if (len > count) | |
898 | len = count; | |
899 | rc = copy_to_user(buf, lbuf, len); | |
900 | kfree(lbuf); | |
901 | if (rc) | |
902 | return -EFAULT; | |
903 | return len; | |
904 | } | |
905 | ||
906 | /* | |
907 | * TODO: To avoid parsing inside kernel and to improve the speed we may | |
908 | * consider use ioctl here | |
909 | */ | |
910 | static ssize_t vga_arb_write(struct file *file, const char __user * buf, | |
911 | size_t count, loff_t *ppos) | |
912 | { | |
913 | struct vga_arb_private *priv = file->private_data; | |
914 | struct vga_arb_user_card *uc = NULL; | |
915 | struct pci_dev *pdev; | |
916 | ||
917 | unsigned int io_state; | |
918 | ||
919 | char *kbuf, *curr_pos; | |
920 | size_t remaining = count; | |
921 | ||
922 | int ret_val; | |
923 | int i; | |
924 | ||
925 | ||
926 | kbuf = kmalloc(count + 1, GFP_KERNEL); | |
927 | if (!kbuf) | |
928 | return -ENOMEM; | |
929 | ||
930 | if (copy_from_user(kbuf, buf, count)) { | |
931 | kfree(kbuf); | |
932 | return -EFAULT; | |
933 | } | |
934 | curr_pos = kbuf; | |
935 | kbuf[count] = '\0'; /* Just to make sure... */ | |
936 | ||
937 | if (strncmp(curr_pos, "lock ", 5) == 0) { | |
938 | curr_pos += 5; | |
939 | remaining -= 5; | |
940 | ||
2d6e9b91 | 941 | pr_debug("client 0x%p called 'lock'\n", priv); |
deb2d2ec BH |
942 | |
943 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
944 | ret_val = -EPROTO; | |
945 | goto done; | |
946 | } | |
947 | if (io_state == VGA_RSRC_NONE) { | |
948 | ret_val = -EPROTO; | |
949 | goto done; | |
950 | } | |
951 | ||
952 | pdev = priv->target; | |
953 | if (priv->target == NULL) { | |
954 | ret_val = -ENODEV; | |
955 | goto done; | |
956 | } | |
957 | ||
958 | vga_get_uninterruptible(pdev, io_state); | |
959 | ||
960 | /* Update the client's locks lists... */ | |
961 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
962 | if (priv->cards[i].pdev == pdev) { | |
963 | if (io_state & VGA_RSRC_LEGACY_IO) | |
964 | priv->cards[i].io_cnt++; | |
965 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
966 | priv->cards[i].mem_cnt++; | |
967 | break; | |
968 | } | |
969 | } | |
970 | ||
971 | ret_val = count; | |
972 | goto done; | |
973 | } else if (strncmp(curr_pos, "unlock ", 7) == 0) { | |
974 | curr_pos += 7; | |
975 | remaining -= 7; | |
976 | ||
2d6e9b91 | 977 | pr_debug("client 0x%p called 'unlock'\n", priv); |
deb2d2ec BH |
978 | |
979 | if (strncmp(curr_pos, "all", 3) == 0) | |
980 | io_state = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
981 | else { | |
982 | if (!vga_str_to_iostate | |
983 | (curr_pos, remaining, &io_state)) { | |
984 | ret_val = -EPROTO; | |
985 | goto done; | |
986 | } | |
987 | /* TODO: Add this? | |
988 | if (io_state == VGA_RSRC_NONE) { | |
989 | ret_val = -EPROTO; | |
990 | goto done; | |
991 | } | |
992 | */ | |
993 | } | |
994 | ||
995 | pdev = priv->target; | |
996 | if (priv->target == NULL) { | |
997 | ret_val = -ENODEV; | |
998 | goto done; | |
999 | } | |
1000 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1001 | if (priv->cards[i].pdev == pdev) | |
1002 | uc = &priv->cards[i]; | |
1003 | } | |
1004 | ||
c916874d JL |
1005 | if (!uc) { |
1006 | ret_val = -EINVAL; | |
1007 | goto done; | |
1008 | } | |
deb2d2ec | 1009 | |
c916874d JL |
1010 | if (io_state & VGA_RSRC_LEGACY_IO && uc->io_cnt == 0) { |
1011 | ret_val = -EINVAL; | |
1012 | goto done; | |
1013 | } | |
deb2d2ec | 1014 | |
c916874d JL |
1015 | if (io_state & VGA_RSRC_LEGACY_MEM && uc->mem_cnt == 0) { |
1016 | ret_val = -EINVAL; | |
1017 | goto done; | |
1018 | } | |
deb2d2ec BH |
1019 | |
1020 | vga_put(pdev, io_state); | |
1021 | ||
1022 | if (io_state & VGA_RSRC_LEGACY_IO) | |
1023 | uc->io_cnt--; | |
1024 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
1025 | uc->mem_cnt--; | |
1026 | ||
1027 | ret_val = count; | |
1028 | goto done; | |
1029 | } else if (strncmp(curr_pos, "trylock ", 8) == 0) { | |
1030 | curr_pos += 8; | |
1031 | remaining -= 8; | |
1032 | ||
2d6e9b91 | 1033 | pr_debug("client 0x%p called 'trylock'\n", priv); |
deb2d2ec BH |
1034 | |
1035 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
1036 | ret_val = -EPROTO; | |
1037 | goto done; | |
1038 | } | |
1039 | /* TODO: Add this? | |
1040 | if (io_state == VGA_RSRC_NONE) { | |
1041 | ret_val = -EPROTO; | |
1042 | goto done; | |
1043 | } | |
1044 | */ | |
1045 | ||
1046 | pdev = priv->target; | |
1047 | if (priv->target == NULL) { | |
1048 | ret_val = -ENODEV; | |
1049 | goto done; | |
1050 | } | |
1051 | ||
1052 | if (vga_tryget(pdev, io_state)) { | |
1053 | /* Update the client's locks lists... */ | |
1054 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1055 | if (priv->cards[i].pdev == pdev) { | |
1056 | if (io_state & VGA_RSRC_LEGACY_IO) | |
1057 | priv->cards[i].io_cnt++; | |
1058 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
1059 | priv->cards[i].mem_cnt++; | |
1060 | break; | |
1061 | } | |
1062 | } | |
1063 | ret_val = count; | |
1064 | goto done; | |
1065 | } else { | |
1066 | ret_val = -EBUSY; | |
1067 | goto done; | |
1068 | } | |
1069 | ||
1070 | } else if (strncmp(curr_pos, "target ", 7) == 0) { | |
1071 | unsigned int domain, bus, devfn; | |
1072 | struct vga_device *vgadev; | |
1073 | ||
1074 | curr_pos += 7; | |
1075 | remaining -= 7; | |
2d6e9b91 | 1076 | pr_debug("client 0x%p called 'target'\n", priv); |
deb2d2ec | 1077 | /* if target is default */ |
2cc9116c | 1078 | if (!strncmp(curr_pos, "default", 7)) |
deb2d2ec BH |
1079 | pdev = pci_dev_get(vga_default_device()); |
1080 | else { | |
1081 | if (!vga_pci_str_to_vars(curr_pos, remaining, | |
1082 | &domain, &bus, &devfn)) { | |
1083 | ret_val = -EPROTO; | |
1084 | goto done; | |
1085 | } | |
2d6e9b91 | 1086 | pr_debug("vgaarb: %s ==> %x:%x:%x.%x\n", curr_pos, |
773a38db MT |
1087 | domain, bus, PCI_SLOT(devfn), PCI_FUNC(devfn)); |
1088 | ||
f85567c8 | 1089 | pdev = pci_get_domain_bus_and_slot(domain, bus, devfn); |
2d6e9b91 | 1090 | pr_debug("vgaarb: pdev %p\n", pdev); |
deb2d2ec | 1091 | if (!pdev) { |
f85567c8 JL |
1092 | pr_err("vgaarb: invalid PCI address %x:%x:%x\n", |
1093 | domain, bus, devfn); | |
deb2d2ec BH |
1094 | ret_val = -ENODEV; |
1095 | goto done; | |
1096 | } | |
1097 | } | |
1098 | ||
1099 | vgadev = vgadev_find(pdev); | |
2d6e9b91 | 1100 | pr_debug("vgaarb: vgadev %p\n", vgadev); |
deb2d2ec | 1101 | if (vgadev == NULL) { |
773a38db | 1102 | pr_err("vgaarb: this pci device is not a vga device\n"); |
deb2d2ec BH |
1103 | pci_dev_put(pdev); |
1104 | ret_val = -ENODEV; | |
1105 | goto done; | |
1106 | } | |
1107 | ||
1108 | priv->target = pdev; | |
1109 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1110 | if (priv->cards[i].pdev == pdev) | |
1111 | break; | |
1112 | if (priv->cards[i].pdev == NULL) { | |
1113 | priv->cards[i].pdev = pdev; | |
1114 | priv->cards[i].io_cnt = 0; | |
1115 | priv->cards[i].mem_cnt = 0; | |
1116 | break; | |
1117 | } | |
1118 | } | |
1119 | if (i == MAX_USER_CARDS) { | |
773a38db MT |
1120 | pr_err("vgaarb: maximum user cards (%d) number reached!\n", |
1121 | MAX_USER_CARDS); | |
deb2d2ec BH |
1122 | pci_dev_put(pdev); |
1123 | /* XXX: which value to return? */ | |
1124 | ret_val = -ENOMEM; | |
1125 | goto done; | |
1126 | } | |
1127 | ||
1128 | ret_val = count; | |
1129 | pci_dev_put(pdev); | |
1130 | goto done; | |
1131 | ||
1132 | ||
1133 | } else if (strncmp(curr_pos, "decodes ", 8) == 0) { | |
1134 | curr_pos += 8; | |
1135 | remaining -= 8; | |
2d6e9b91 | 1136 | pr_debug("vgaarb: client 0x%p called 'decodes'\n", priv); |
deb2d2ec BH |
1137 | |
1138 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
1139 | ret_val = -EPROTO; | |
1140 | goto done; | |
1141 | } | |
1142 | pdev = priv->target; | |
1143 | if (priv->target == NULL) { | |
1144 | ret_val = -ENODEV; | |
1145 | goto done; | |
1146 | } | |
1147 | ||
1148 | __vga_set_legacy_decoding(pdev, io_state, true); | |
1149 | ret_val = count; | |
1150 | goto done; | |
1151 | } | |
1152 | /* If we got here, the message written is not part of the protocol! */ | |
1153 | kfree(kbuf); | |
1154 | return -EPROTO; | |
1155 | ||
1156 | done: | |
1157 | kfree(kbuf); | |
1158 | return ret_val; | |
1159 | } | |
1160 | ||
1161 | static unsigned int vga_arb_fpoll(struct file *file, poll_table * wait) | |
1162 | { | |
1163 | struct vga_arb_private *priv = file->private_data; | |
1164 | ||
2d6e9b91 | 1165 | pr_debug("%s\n", __func__); |
deb2d2ec BH |
1166 | |
1167 | if (priv == NULL) | |
1168 | return -ENODEV; | |
1169 | poll_wait(file, &vga_wait_queue, wait); | |
1170 | return POLLIN; | |
1171 | } | |
1172 | ||
1173 | static int vga_arb_open(struct inode *inode, struct file *file) | |
1174 | { | |
1175 | struct vga_arb_private *priv; | |
1176 | unsigned long flags; | |
1177 | ||
2d6e9b91 | 1178 | pr_debug("%s\n", __func__); |
deb2d2ec | 1179 | |
f35119d6 | 1180 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); |
deb2d2ec BH |
1181 | if (priv == NULL) |
1182 | return -ENOMEM; | |
deb2d2ec BH |
1183 | spin_lock_init(&priv->lock); |
1184 | file->private_data = priv; | |
1185 | ||
1186 | spin_lock_irqsave(&vga_user_lock, flags); | |
1187 | list_add(&priv->list, &vga_user_list); | |
1188 | spin_unlock_irqrestore(&vga_user_lock, flags); | |
1189 | ||
1190 | /* Set the client' lists of locks */ | |
1191 | priv->target = vga_default_device(); /* Maybe this is still null! */ | |
1192 | priv->cards[0].pdev = priv->target; | |
1193 | priv->cards[0].io_cnt = 0; | |
1194 | priv->cards[0].mem_cnt = 0; | |
1195 | ||
1196 | ||
1197 | return 0; | |
1198 | } | |
1199 | ||
1200 | static int vga_arb_release(struct inode *inode, struct file *file) | |
1201 | { | |
1202 | struct vga_arb_private *priv = file->private_data; | |
1203 | struct vga_arb_user_card *uc; | |
1204 | unsigned long flags; | |
1205 | int i; | |
1206 | ||
2d6e9b91 | 1207 | pr_debug("%s\n", __func__); |
deb2d2ec BH |
1208 | |
1209 | if (priv == NULL) | |
1210 | return -ENODEV; | |
1211 | ||
1212 | spin_lock_irqsave(&vga_user_lock, flags); | |
1213 | list_del(&priv->list); | |
1214 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1215 | uc = &priv->cards[i]; | |
1216 | if (uc->pdev == NULL) | |
1217 | continue; | |
2d6e9b91 | 1218 | pr_debug("uc->io_cnt == %d, uc->mem_cnt == %d\n", |
deb2d2ec BH |
1219 | uc->io_cnt, uc->mem_cnt); |
1220 | while (uc->io_cnt--) | |
1221 | vga_put(uc->pdev, VGA_RSRC_LEGACY_IO); | |
1222 | while (uc->mem_cnt--) | |
1223 | vga_put(uc->pdev, VGA_RSRC_LEGACY_MEM); | |
1224 | } | |
1225 | spin_unlock_irqrestore(&vga_user_lock, flags); | |
1226 | ||
1227 | kfree(priv); | |
1228 | ||
1229 | return 0; | |
1230 | } | |
1231 | ||
1232 | static void vga_arb_device_card_gone(struct pci_dev *pdev) | |
1233 | { | |
1234 | } | |
1235 | ||
1236 | /* | |
1237 | * callback any registered clients to let them know we have a | |
1238 | * change in VGA cards | |
1239 | */ | |
1240 | static void vga_arbiter_notify_clients(void) | |
1241 | { | |
1242 | struct vga_device *vgadev; | |
1243 | unsigned long flags; | |
1244 | uint32_t new_decodes; | |
1245 | bool new_state; | |
1246 | ||
1247 | if (!vga_arbiter_used) | |
1248 | return; | |
1249 | ||
1250 | spin_lock_irqsave(&vga_lock, flags); | |
1251 | list_for_each_entry(vgadev, &vga_list, list) { | |
1252 | if (vga_count > 1) | |
1253 | new_state = false; | |
1254 | else | |
1255 | new_state = true; | |
1256 | if (vgadev->set_vga_decode) { | |
1257 | new_decodes = vgadev->set_vga_decode(vgadev->cookie, new_state); | |
1258 | vga_update_device_decodes(vgadev, new_decodes); | |
1259 | } | |
1260 | } | |
1261 | spin_unlock_irqrestore(&vga_lock, flags); | |
1262 | } | |
1263 | ||
1264 | static int pci_notify(struct notifier_block *nb, unsigned long action, | |
1265 | void *data) | |
1266 | { | |
1267 | struct device *dev = data; | |
1268 | struct pci_dev *pdev = to_pci_dev(dev); | |
1269 | bool notify = false; | |
1270 | ||
2d6e9b91 | 1271 | pr_debug("%s\n", __func__); |
deb2d2ec BH |
1272 | |
1273 | /* For now we're only intereted in devices added and removed. I didn't | |
1274 | * test this thing here, so someone needs to double check for the | |
1275 | * cases of hotplugable vga cards. */ | |
1276 | if (action == BUS_NOTIFY_ADD_DEVICE) | |
1277 | notify = vga_arbiter_add_pci_device(pdev); | |
1278 | else if (action == BUS_NOTIFY_DEL_DEVICE) | |
1279 | notify = vga_arbiter_del_pci_device(pdev); | |
1280 | ||
1281 | if (notify) | |
1282 | vga_arbiter_notify_clients(); | |
1283 | return 0; | |
1284 | } | |
1285 | ||
1286 | static struct notifier_block pci_notifier = { | |
1287 | .notifier_call = pci_notify, | |
1288 | }; | |
1289 | ||
1290 | static const struct file_operations vga_arb_device_fops = { | |
1291 | .read = vga_arb_read, | |
1292 | .write = vga_arb_write, | |
1293 | .poll = vga_arb_fpoll, | |
1294 | .open = vga_arb_open, | |
1295 | .release = vga_arb_release, | |
6038f373 | 1296 | .llseek = noop_llseek, |
deb2d2ec BH |
1297 | }; |
1298 | ||
1299 | static struct miscdevice vga_arb_device = { | |
1300 | MISC_DYNAMIC_MINOR, "vga_arbiter", &vga_arb_device_fops | |
1301 | }; | |
1302 | ||
1303 | static int __init vga_arb_device_init(void) | |
1304 | { | |
1305 | int rc; | |
1306 | struct pci_dev *pdev; | |
3448a19d | 1307 | struct vga_device *vgadev; |
deb2d2ec BH |
1308 | |
1309 | rc = misc_register(&vga_arb_device); | |
1310 | if (rc < 0) | |
1311 | pr_err("vgaarb: error %d registering device\n", rc); | |
1312 | ||
1313 | bus_register_notifier(&pci_bus_type, &pci_notifier); | |
1314 | ||
1315 | /* We add all pci devices satisfying vga class in the arbiter by | |
1316 | * default */ | |
1317 | pdev = NULL; | |
1318 | while ((pdev = | |
1319 | pci_get_subsys(PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, | |
1320 | PCI_ANY_ID, pdev)) != NULL) | |
1321 | vga_arbiter_add_pci_device(pdev); | |
1322 | ||
1323 | pr_info("vgaarb: loaded\n"); | |
3448a19d DA |
1324 | |
1325 | list_for_each_entry(vgadev, &vga_list, list) { | |
1326 | if (vgadev->bridge_has_one_vga) | |
1327 | pr_info("vgaarb: bridge control possible %s\n", pci_name(vgadev->pdev)); | |
1328 | else | |
1329 | pr_info("vgaarb: no bridge control possible %s\n", pci_name(vgadev->pdev)); | |
1330 | } | |
deb2d2ec BH |
1331 | return rc; |
1332 | } | |
1333 | subsys_initcall(vga_arb_device_init); |