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; | |
f22d776f | 260 | if (match & (VGA_RSRC_LEGACY_MEM|VGA_RSRC_NORMAL_MEM)) |
3448a19d | 261 | pci_bits |= PCI_COMMAND_MEMORY; |
f22d776f | 262 | if (match & (VGA_RSRC_LEGACY_IO|VGA_RSRC_NORMAL_IO)) |
3448a19d DA |
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); | |
f22d776f | 270 | conflict->owns &= ~match; |
deb2d2ec | 271 | /* If he also owned non-legacy, that is no longer the case */ |
f22d776f | 272 | if (match & VGA_RSRC_LEGACY_MEM) |
deb2d2ec | 273 | conflict->owns &= ~VGA_RSRC_NORMAL_MEM; |
f22d776f | 274 | if (match & VGA_RSRC_LEGACY_IO) |
deb2d2ec BH |
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 | { | |
5c0f6ee7 | 647 | int old_decodes, decodes_removed, decodes_unlocked; |
deb2d2ec BH |
648 | |
649 | old_decodes = vgadev->decodes; | |
5c0f6ee7 AW |
650 | decodes_removed = ~new_decodes & old_decodes; |
651 | decodes_unlocked = vgadev->locks & decodes_removed; | |
652 | vgadev->owns &= ~decodes_removed; | |
deb2d2ec BH |
653 | vgadev->decodes = new_decodes; |
654 | ||
655 | pr_info("vgaarb: device changed decodes: PCI:%s,olddecodes=%s,decodes=%s:owns=%s\n", | |
656 | pci_name(vgadev->pdev), | |
657 | vga_iostate_to_str(old_decodes), | |
658 | vga_iostate_to_str(vgadev->decodes), | |
659 | vga_iostate_to_str(vgadev->owns)); | |
660 | ||
5c0f6ee7 AW |
661 | /* if we removed locked decodes, lock count goes to zero, and release */ |
662 | if (decodes_unlocked) { | |
663 | if (decodes_unlocked & VGA_RSRC_LEGACY_IO) | |
664 | vgadev->io_lock_cnt = 0; | |
665 | if (decodes_unlocked & VGA_RSRC_LEGACY_MEM) | |
666 | vgadev->mem_lock_cnt = 0; | |
667 | __vga_put(vgadev, decodes_unlocked); | |
deb2d2ec BH |
668 | } |
669 | ||
670 | /* change decodes counter */ | |
5c0f6ee7 AW |
671 | if (old_decodes & VGA_RSRC_LEGACY_MASK && |
672 | !(new_decodes & VGA_RSRC_LEGACY_MASK)) | |
673 | vga_decode_count--; | |
674 | if (!(old_decodes & VGA_RSRC_LEGACY_MASK) && | |
675 | new_decodes & VGA_RSRC_LEGACY_MASK) | |
676 | vga_decode_count++; | |
2d6e9b91 | 677 | pr_debug("vgaarb: decoding count now is: %d\n", vga_decode_count); |
deb2d2ec BH |
678 | } |
679 | ||
201ba4c4 | 680 | static void __vga_set_legacy_decoding(struct pci_dev *pdev, unsigned int decodes, bool userspace) |
deb2d2ec BH |
681 | { |
682 | struct vga_device *vgadev; | |
683 | unsigned long flags; | |
684 | ||
685 | decodes &= VGA_RSRC_LEGACY_MASK; | |
686 | ||
687 | spin_lock_irqsave(&vga_lock, flags); | |
688 | vgadev = vgadev_find(pdev); | |
689 | if (vgadev == NULL) | |
690 | goto bail; | |
691 | ||
692 | /* don't let userspace futz with kernel driver decodes */ | |
693 | if (userspace && vgadev->set_vga_decode) | |
694 | goto bail; | |
695 | ||
696 | /* update the device decodes + counter */ | |
697 | vga_update_device_decodes(vgadev, decodes); | |
698 | ||
699 | /* XXX if somebody is going from "doesn't decode" to "decodes" state | |
700 | * here, additional care must be taken as we may have pending owner | |
701 | * ship of non-legacy region ... | |
702 | */ | |
703 | bail: | |
704 | spin_unlock_irqrestore(&vga_lock, flags); | |
705 | } | |
706 | ||
707 | void vga_set_legacy_decoding(struct pci_dev *pdev, unsigned int decodes) | |
708 | { | |
709 | __vga_set_legacy_decoding(pdev, decodes, false); | |
710 | } | |
711 | EXPORT_SYMBOL(vga_set_legacy_decoding); | |
712 | ||
deb2d2ec BH |
713 | /* call with NULL to unregister */ |
714 | int vga_client_register(struct pci_dev *pdev, void *cookie, | |
715 | void (*irq_set_state)(void *cookie, bool state), | |
716 | unsigned int (*set_vga_decode)(void *cookie, bool decode)) | |
717 | { | |
934f992c | 718 | int ret = -ENODEV; |
deb2d2ec BH |
719 | struct vga_device *vgadev; |
720 | unsigned long flags; | |
721 | ||
722 | spin_lock_irqsave(&vga_lock, flags); | |
723 | vgadev = vgadev_find(pdev); | |
724 | if (!vgadev) | |
725 | goto bail; | |
726 | ||
727 | vgadev->irq_set_state = irq_set_state; | |
728 | vgadev->set_vga_decode = set_vga_decode; | |
729 | vgadev->cookie = cookie; | |
730 | ret = 0; | |
731 | ||
732 | bail: | |
733 | spin_unlock_irqrestore(&vga_lock, flags); | |
734 | return ret; | |
735 | ||
736 | } | |
737 | EXPORT_SYMBOL(vga_client_register); | |
738 | ||
739 | /* | |
740 | * Char driver implementation | |
741 | * | |
742 | * Semantics is: | |
743 | * | |
744 | * open : open user instance of the arbitrer. by default, it's | |
745 | * attached to the default VGA device of the system. | |
746 | * | |
747 | * close : close user instance, release locks | |
748 | * | |
749 | * read : return a string indicating the status of the target. | |
750 | * an IO state string is of the form {io,mem,io+mem,none}, | |
751 | * mc and ic are respectively mem and io lock counts (for | |
752 | * debugging/diagnostic only). "decodes" indicate what the | |
753 | * card currently decodes, "owns" indicates what is currently | |
754 | * enabled on it, and "locks" indicates what is locked by this | |
755 | * card. If the card is unplugged, we get "invalid" then for | |
756 | * card_ID and an -ENODEV error is returned for any command | |
757 | * until a new card is targeted | |
758 | * | |
759 | * "<card_ID>,decodes=<io_state>,owns=<io_state>,locks=<io_state> (ic,mc)" | |
760 | * | |
761 | * write : write a command to the arbiter. List of commands is: | |
762 | * | |
763 | * target <card_ID> : switch target to card <card_ID> (see below) | |
764 | * lock <io_state> : acquires locks on target ("none" is invalid io_state) | |
765 | * trylock <io_state> : non-blocking acquire locks on target | |
766 | * unlock <io_state> : release locks on target | |
767 | * unlock all : release all locks on target held by this user | |
768 | * decodes <io_state> : set the legacy decoding attributes for the card | |
769 | * | |
770 | * poll : event if something change on any card (not just the target) | |
771 | * | |
772 | * card_ID is of the form "PCI:domain:bus:dev.fn". It can be set to "default" | |
773 | * to go back to the system default card (TODO: not implemented yet). | |
774 | * Currently, only PCI is supported as a prefix, but the userland API may | |
775 | * support other bus types in the future, even if the current kernel | |
776 | * implementation doesn't. | |
777 | * | |
778 | * Note about locks: | |
779 | * | |
780 | * The driver keeps track of which user has what locks on which card. It | |
781 | * supports stacking, like the kernel one. This complexifies the implementation | |
782 | * a bit, but makes the arbiter more tolerant to userspace problems and able | |
783 | * to properly cleanup in all cases when a process dies. | |
784 | * Currently, a max of 16 cards simultaneously can have locks issued from | |
785 | * userspace for a given user (file descriptor instance) of the arbiter. | |
786 | * | |
787 | * If the device is hot-unplugged, there is a hook inside the module to notify | |
788 | * they being added/removed in the system and automatically added/removed in | |
789 | * the arbiter. | |
790 | */ | |
791 | ||
36028f33 | 792 | #define MAX_USER_CARDS CONFIG_VGA_ARB_MAX_GPUS |
deb2d2ec BH |
793 | #define PCI_INVALID_CARD ((struct pci_dev *)-1UL) |
794 | ||
795 | /* | |
796 | * Each user has an array of these, tracking which cards have locks | |
797 | */ | |
798 | struct vga_arb_user_card { | |
799 | struct pci_dev *pdev; | |
800 | unsigned int mem_cnt; | |
801 | unsigned int io_cnt; | |
802 | }; | |
803 | ||
804 | struct vga_arb_private { | |
805 | struct list_head list; | |
806 | struct pci_dev *target; | |
807 | struct vga_arb_user_card cards[MAX_USER_CARDS]; | |
808 | spinlock_t lock; | |
809 | }; | |
810 | ||
811 | static LIST_HEAD(vga_user_list); | |
812 | static DEFINE_SPINLOCK(vga_user_lock); | |
813 | ||
814 | ||
815 | /* | |
816 | * This function gets a string in the format: "PCI:domain:bus:dev.fn" and | |
817 | * returns the respective values. If the string is not in this format, | |
818 | * it returns 0. | |
819 | */ | |
820 | static int vga_pci_str_to_vars(char *buf, int count, unsigned int *domain, | |
821 | unsigned int *bus, unsigned int *devfn) | |
822 | { | |
823 | int n; | |
824 | unsigned int slot, func; | |
825 | ||
826 | ||
827 | n = sscanf(buf, "PCI:%x:%x:%x.%x", domain, bus, &slot, &func); | |
828 | if (n != 4) | |
829 | return 0; | |
830 | ||
831 | *devfn = PCI_DEVFN(slot, func); | |
832 | ||
833 | return 1; | |
834 | } | |
835 | ||
836 | static ssize_t vga_arb_read(struct file *file, char __user * buf, | |
837 | size_t count, loff_t *ppos) | |
838 | { | |
839 | struct vga_arb_private *priv = file->private_data; | |
840 | struct vga_device *vgadev; | |
841 | struct pci_dev *pdev; | |
842 | unsigned long flags; | |
843 | size_t len; | |
844 | int rc; | |
845 | char *lbuf; | |
846 | ||
847 | lbuf = kmalloc(1024, GFP_KERNEL); | |
848 | if (lbuf == NULL) | |
849 | return -ENOMEM; | |
850 | ||
851 | /* Shields against vga_arb_device_card_gone (pci_dev going | |
852 | * away), and allows access to vga list | |
853 | */ | |
854 | spin_lock_irqsave(&vga_lock, flags); | |
855 | ||
25985edc | 856 | /* If we are targeting the default, use it */ |
deb2d2ec BH |
857 | pdev = priv->target; |
858 | if (pdev == NULL || pdev == PCI_INVALID_CARD) { | |
859 | spin_unlock_irqrestore(&vga_lock, flags); | |
860 | len = sprintf(lbuf, "invalid"); | |
861 | goto done; | |
862 | } | |
863 | ||
864 | /* Find card vgadev structure */ | |
865 | vgadev = vgadev_find(pdev); | |
866 | if (vgadev == NULL) { | |
867 | /* Wow, it's not in the list, that shouldn't happen, | |
868 | * let's fix us up and return invalid card | |
869 | */ | |
870 | if (pdev == priv->target) | |
871 | vga_arb_device_card_gone(pdev); | |
872 | spin_unlock_irqrestore(&vga_lock, flags); | |
873 | len = sprintf(lbuf, "invalid"); | |
874 | goto done; | |
875 | } | |
876 | ||
877 | /* Fill the buffer with infos */ | |
878 | len = snprintf(lbuf, 1024, | |
879 | "count:%d,PCI:%s,decodes=%s,owns=%s,locks=%s(%d:%d)\n", | |
880 | vga_decode_count, pci_name(pdev), | |
881 | vga_iostate_to_str(vgadev->decodes), | |
882 | vga_iostate_to_str(vgadev->owns), | |
883 | vga_iostate_to_str(vgadev->locks), | |
884 | vgadev->io_lock_cnt, vgadev->mem_lock_cnt); | |
885 | ||
886 | spin_unlock_irqrestore(&vga_lock, flags); | |
887 | done: | |
888 | ||
889 | /* Copy that to user */ | |
890 | if (len > count) | |
891 | len = count; | |
892 | rc = copy_to_user(buf, lbuf, len); | |
893 | kfree(lbuf); | |
894 | if (rc) | |
895 | return -EFAULT; | |
896 | return len; | |
897 | } | |
898 | ||
899 | /* | |
900 | * TODO: To avoid parsing inside kernel and to improve the speed we may | |
901 | * consider use ioctl here | |
902 | */ | |
903 | static ssize_t vga_arb_write(struct file *file, const char __user * buf, | |
904 | size_t count, loff_t *ppos) | |
905 | { | |
906 | struct vga_arb_private *priv = file->private_data; | |
907 | struct vga_arb_user_card *uc = NULL; | |
908 | struct pci_dev *pdev; | |
909 | ||
910 | unsigned int io_state; | |
911 | ||
912 | char *kbuf, *curr_pos; | |
913 | size_t remaining = count; | |
914 | ||
915 | int ret_val; | |
916 | int i; | |
917 | ||
918 | ||
919 | kbuf = kmalloc(count + 1, GFP_KERNEL); | |
920 | if (!kbuf) | |
921 | return -ENOMEM; | |
922 | ||
923 | if (copy_from_user(kbuf, buf, count)) { | |
924 | kfree(kbuf); | |
925 | return -EFAULT; | |
926 | } | |
927 | curr_pos = kbuf; | |
928 | kbuf[count] = '\0'; /* Just to make sure... */ | |
929 | ||
930 | if (strncmp(curr_pos, "lock ", 5) == 0) { | |
931 | curr_pos += 5; | |
932 | remaining -= 5; | |
933 | ||
2d6e9b91 | 934 | pr_debug("client 0x%p called 'lock'\n", priv); |
deb2d2ec BH |
935 | |
936 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
937 | ret_val = -EPROTO; | |
938 | goto done; | |
939 | } | |
940 | if (io_state == VGA_RSRC_NONE) { | |
941 | ret_val = -EPROTO; | |
942 | goto done; | |
943 | } | |
944 | ||
945 | pdev = priv->target; | |
946 | if (priv->target == NULL) { | |
947 | ret_val = -ENODEV; | |
948 | goto done; | |
949 | } | |
950 | ||
951 | vga_get_uninterruptible(pdev, io_state); | |
952 | ||
953 | /* Update the client's locks lists... */ | |
954 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
955 | if (priv->cards[i].pdev == pdev) { | |
956 | if (io_state & VGA_RSRC_LEGACY_IO) | |
957 | priv->cards[i].io_cnt++; | |
958 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
959 | priv->cards[i].mem_cnt++; | |
960 | break; | |
961 | } | |
962 | } | |
963 | ||
964 | ret_val = count; | |
965 | goto done; | |
966 | } else if (strncmp(curr_pos, "unlock ", 7) == 0) { | |
967 | curr_pos += 7; | |
968 | remaining -= 7; | |
969 | ||
2d6e9b91 | 970 | pr_debug("client 0x%p called 'unlock'\n", priv); |
deb2d2ec BH |
971 | |
972 | if (strncmp(curr_pos, "all", 3) == 0) | |
973 | io_state = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; | |
974 | else { | |
975 | if (!vga_str_to_iostate | |
976 | (curr_pos, remaining, &io_state)) { | |
977 | ret_val = -EPROTO; | |
978 | goto done; | |
979 | } | |
980 | /* TODO: Add this? | |
981 | if (io_state == VGA_RSRC_NONE) { | |
982 | ret_val = -EPROTO; | |
983 | goto done; | |
984 | } | |
985 | */ | |
986 | } | |
987 | ||
988 | pdev = priv->target; | |
989 | if (priv->target == NULL) { | |
990 | ret_val = -ENODEV; | |
991 | goto done; | |
992 | } | |
993 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
994 | if (priv->cards[i].pdev == pdev) | |
995 | uc = &priv->cards[i]; | |
996 | } | |
997 | ||
c916874d JL |
998 | if (!uc) { |
999 | ret_val = -EINVAL; | |
1000 | goto done; | |
1001 | } | |
deb2d2ec | 1002 | |
c916874d JL |
1003 | if (io_state & VGA_RSRC_LEGACY_IO && uc->io_cnt == 0) { |
1004 | ret_val = -EINVAL; | |
1005 | goto done; | |
1006 | } | |
deb2d2ec | 1007 | |
c916874d JL |
1008 | if (io_state & VGA_RSRC_LEGACY_MEM && uc->mem_cnt == 0) { |
1009 | ret_val = -EINVAL; | |
1010 | goto done; | |
1011 | } | |
deb2d2ec BH |
1012 | |
1013 | vga_put(pdev, io_state); | |
1014 | ||
1015 | if (io_state & VGA_RSRC_LEGACY_IO) | |
1016 | uc->io_cnt--; | |
1017 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
1018 | uc->mem_cnt--; | |
1019 | ||
1020 | ret_val = count; | |
1021 | goto done; | |
1022 | } else if (strncmp(curr_pos, "trylock ", 8) == 0) { | |
1023 | curr_pos += 8; | |
1024 | remaining -= 8; | |
1025 | ||
2d6e9b91 | 1026 | pr_debug("client 0x%p called 'trylock'\n", priv); |
deb2d2ec BH |
1027 | |
1028 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
1029 | ret_val = -EPROTO; | |
1030 | goto done; | |
1031 | } | |
1032 | /* TODO: Add this? | |
1033 | if (io_state == VGA_RSRC_NONE) { | |
1034 | ret_val = -EPROTO; | |
1035 | goto done; | |
1036 | } | |
1037 | */ | |
1038 | ||
1039 | pdev = priv->target; | |
1040 | if (priv->target == NULL) { | |
1041 | ret_val = -ENODEV; | |
1042 | goto done; | |
1043 | } | |
1044 | ||
1045 | if (vga_tryget(pdev, io_state)) { | |
1046 | /* Update the client's locks lists... */ | |
1047 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1048 | if (priv->cards[i].pdev == pdev) { | |
1049 | if (io_state & VGA_RSRC_LEGACY_IO) | |
1050 | priv->cards[i].io_cnt++; | |
1051 | if (io_state & VGA_RSRC_LEGACY_MEM) | |
1052 | priv->cards[i].mem_cnt++; | |
1053 | break; | |
1054 | } | |
1055 | } | |
1056 | ret_val = count; | |
1057 | goto done; | |
1058 | } else { | |
1059 | ret_val = -EBUSY; | |
1060 | goto done; | |
1061 | } | |
1062 | ||
1063 | } else if (strncmp(curr_pos, "target ", 7) == 0) { | |
1064 | unsigned int domain, bus, devfn; | |
1065 | struct vga_device *vgadev; | |
1066 | ||
1067 | curr_pos += 7; | |
1068 | remaining -= 7; | |
2d6e9b91 | 1069 | pr_debug("client 0x%p called 'target'\n", priv); |
deb2d2ec | 1070 | /* if target is default */ |
2cc9116c | 1071 | if (!strncmp(curr_pos, "default", 7)) |
deb2d2ec BH |
1072 | pdev = pci_dev_get(vga_default_device()); |
1073 | else { | |
1074 | if (!vga_pci_str_to_vars(curr_pos, remaining, | |
1075 | &domain, &bus, &devfn)) { | |
1076 | ret_val = -EPROTO; | |
1077 | goto done; | |
1078 | } | |
2d6e9b91 | 1079 | pr_debug("vgaarb: %s ==> %x:%x:%x.%x\n", curr_pos, |
773a38db MT |
1080 | domain, bus, PCI_SLOT(devfn), PCI_FUNC(devfn)); |
1081 | ||
f85567c8 | 1082 | pdev = pci_get_domain_bus_and_slot(domain, bus, devfn); |
2d6e9b91 | 1083 | pr_debug("vgaarb: pdev %p\n", pdev); |
deb2d2ec | 1084 | if (!pdev) { |
f85567c8 JL |
1085 | pr_err("vgaarb: invalid PCI address %x:%x:%x\n", |
1086 | domain, bus, devfn); | |
deb2d2ec BH |
1087 | ret_val = -ENODEV; |
1088 | goto done; | |
1089 | } | |
1090 | } | |
1091 | ||
1092 | vgadev = vgadev_find(pdev); | |
2d6e9b91 | 1093 | pr_debug("vgaarb: vgadev %p\n", vgadev); |
deb2d2ec | 1094 | if (vgadev == NULL) { |
773a38db | 1095 | pr_err("vgaarb: this pci device is not a vga device\n"); |
deb2d2ec BH |
1096 | pci_dev_put(pdev); |
1097 | ret_val = -ENODEV; | |
1098 | goto done; | |
1099 | } | |
1100 | ||
1101 | priv->target = pdev; | |
1102 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1103 | if (priv->cards[i].pdev == pdev) | |
1104 | break; | |
1105 | if (priv->cards[i].pdev == NULL) { | |
1106 | priv->cards[i].pdev = pdev; | |
1107 | priv->cards[i].io_cnt = 0; | |
1108 | priv->cards[i].mem_cnt = 0; | |
1109 | break; | |
1110 | } | |
1111 | } | |
1112 | if (i == MAX_USER_CARDS) { | |
773a38db MT |
1113 | pr_err("vgaarb: maximum user cards (%d) number reached!\n", |
1114 | MAX_USER_CARDS); | |
deb2d2ec BH |
1115 | pci_dev_put(pdev); |
1116 | /* XXX: which value to return? */ | |
1117 | ret_val = -ENOMEM; | |
1118 | goto done; | |
1119 | } | |
1120 | ||
1121 | ret_val = count; | |
1122 | pci_dev_put(pdev); | |
1123 | goto done; | |
1124 | ||
1125 | ||
1126 | } else if (strncmp(curr_pos, "decodes ", 8) == 0) { | |
1127 | curr_pos += 8; | |
1128 | remaining -= 8; | |
2d6e9b91 | 1129 | pr_debug("vgaarb: client 0x%p called 'decodes'\n", priv); |
deb2d2ec BH |
1130 | |
1131 | if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { | |
1132 | ret_val = -EPROTO; | |
1133 | goto done; | |
1134 | } | |
1135 | pdev = priv->target; | |
1136 | if (priv->target == NULL) { | |
1137 | ret_val = -ENODEV; | |
1138 | goto done; | |
1139 | } | |
1140 | ||
1141 | __vga_set_legacy_decoding(pdev, io_state, true); | |
1142 | ret_val = count; | |
1143 | goto done; | |
1144 | } | |
1145 | /* If we got here, the message written is not part of the protocol! */ | |
1146 | kfree(kbuf); | |
1147 | return -EPROTO; | |
1148 | ||
1149 | done: | |
1150 | kfree(kbuf); | |
1151 | return ret_val; | |
1152 | } | |
1153 | ||
1154 | static unsigned int vga_arb_fpoll(struct file *file, poll_table * wait) | |
1155 | { | |
1156 | struct vga_arb_private *priv = file->private_data; | |
1157 | ||
2d6e9b91 | 1158 | pr_debug("%s\n", __func__); |
deb2d2ec BH |
1159 | |
1160 | if (priv == NULL) | |
1161 | return -ENODEV; | |
1162 | poll_wait(file, &vga_wait_queue, wait); | |
1163 | return POLLIN; | |
1164 | } | |
1165 | ||
1166 | static int vga_arb_open(struct inode *inode, struct file *file) | |
1167 | { | |
1168 | struct vga_arb_private *priv; | |
1169 | unsigned long flags; | |
1170 | ||
2d6e9b91 | 1171 | pr_debug("%s\n", __func__); |
deb2d2ec | 1172 | |
f35119d6 | 1173 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); |
deb2d2ec BH |
1174 | if (priv == NULL) |
1175 | return -ENOMEM; | |
deb2d2ec BH |
1176 | spin_lock_init(&priv->lock); |
1177 | file->private_data = priv; | |
1178 | ||
1179 | spin_lock_irqsave(&vga_user_lock, flags); | |
1180 | list_add(&priv->list, &vga_user_list); | |
1181 | spin_unlock_irqrestore(&vga_user_lock, flags); | |
1182 | ||
1183 | /* Set the client' lists of locks */ | |
1184 | priv->target = vga_default_device(); /* Maybe this is still null! */ | |
1185 | priv->cards[0].pdev = priv->target; | |
1186 | priv->cards[0].io_cnt = 0; | |
1187 | priv->cards[0].mem_cnt = 0; | |
1188 | ||
1189 | ||
1190 | return 0; | |
1191 | } | |
1192 | ||
1193 | static int vga_arb_release(struct inode *inode, struct file *file) | |
1194 | { | |
1195 | struct vga_arb_private *priv = file->private_data; | |
1196 | struct vga_arb_user_card *uc; | |
1197 | unsigned long flags; | |
1198 | int i; | |
1199 | ||
2d6e9b91 | 1200 | pr_debug("%s\n", __func__); |
deb2d2ec BH |
1201 | |
1202 | if (priv == NULL) | |
1203 | return -ENODEV; | |
1204 | ||
1205 | spin_lock_irqsave(&vga_user_lock, flags); | |
1206 | list_del(&priv->list); | |
1207 | for (i = 0; i < MAX_USER_CARDS; i++) { | |
1208 | uc = &priv->cards[i]; | |
1209 | if (uc->pdev == NULL) | |
1210 | continue; | |
2d6e9b91 | 1211 | pr_debug("uc->io_cnt == %d, uc->mem_cnt == %d\n", |
deb2d2ec BH |
1212 | uc->io_cnt, uc->mem_cnt); |
1213 | while (uc->io_cnt--) | |
1214 | vga_put(uc->pdev, VGA_RSRC_LEGACY_IO); | |
1215 | while (uc->mem_cnt--) | |
1216 | vga_put(uc->pdev, VGA_RSRC_LEGACY_MEM); | |
1217 | } | |
1218 | spin_unlock_irqrestore(&vga_user_lock, flags); | |
1219 | ||
1220 | kfree(priv); | |
1221 | ||
1222 | return 0; | |
1223 | } | |
1224 | ||
1225 | static void vga_arb_device_card_gone(struct pci_dev *pdev) | |
1226 | { | |
1227 | } | |
1228 | ||
1229 | /* | |
1230 | * callback any registered clients to let them know we have a | |
1231 | * change in VGA cards | |
1232 | */ | |
1233 | static void vga_arbiter_notify_clients(void) | |
1234 | { | |
1235 | struct vga_device *vgadev; | |
1236 | unsigned long flags; | |
1237 | uint32_t new_decodes; | |
1238 | bool new_state; | |
1239 | ||
1240 | if (!vga_arbiter_used) | |
1241 | return; | |
1242 | ||
1243 | spin_lock_irqsave(&vga_lock, flags); | |
1244 | list_for_each_entry(vgadev, &vga_list, list) { | |
1245 | if (vga_count > 1) | |
1246 | new_state = false; | |
1247 | else | |
1248 | new_state = true; | |
1249 | if (vgadev->set_vga_decode) { | |
1250 | new_decodes = vgadev->set_vga_decode(vgadev->cookie, new_state); | |
1251 | vga_update_device_decodes(vgadev, new_decodes); | |
1252 | } | |
1253 | } | |
1254 | spin_unlock_irqrestore(&vga_lock, flags); | |
1255 | } | |
1256 | ||
1257 | static int pci_notify(struct notifier_block *nb, unsigned long action, | |
1258 | void *data) | |
1259 | { | |
1260 | struct device *dev = data; | |
1261 | struct pci_dev *pdev = to_pci_dev(dev); | |
1262 | bool notify = false; | |
1263 | ||
2d6e9b91 | 1264 | pr_debug("%s\n", __func__); |
deb2d2ec BH |
1265 | |
1266 | /* For now we're only intereted in devices added and removed. I didn't | |
1267 | * test this thing here, so someone needs to double check for the | |
1268 | * cases of hotplugable vga cards. */ | |
1269 | if (action == BUS_NOTIFY_ADD_DEVICE) | |
1270 | notify = vga_arbiter_add_pci_device(pdev); | |
1271 | else if (action == BUS_NOTIFY_DEL_DEVICE) | |
1272 | notify = vga_arbiter_del_pci_device(pdev); | |
1273 | ||
1274 | if (notify) | |
1275 | vga_arbiter_notify_clients(); | |
1276 | return 0; | |
1277 | } | |
1278 | ||
1279 | static struct notifier_block pci_notifier = { | |
1280 | .notifier_call = pci_notify, | |
1281 | }; | |
1282 | ||
1283 | static const struct file_operations vga_arb_device_fops = { | |
1284 | .read = vga_arb_read, | |
1285 | .write = vga_arb_write, | |
1286 | .poll = vga_arb_fpoll, | |
1287 | .open = vga_arb_open, | |
1288 | .release = vga_arb_release, | |
6038f373 | 1289 | .llseek = noop_llseek, |
deb2d2ec BH |
1290 | }; |
1291 | ||
1292 | static struct miscdevice vga_arb_device = { | |
1293 | MISC_DYNAMIC_MINOR, "vga_arbiter", &vga_arb_device_fops | |
1294 | }; | |
1295 | ||
1296 | static int __init vga_arb_device_init(void) | |
1297 | { | |
1298 | int rc; | |
1299 | struct pci_dev *pdev; | |
3448a19d | 1300 | struct vga_device *vgadev; |
deb2d2ec BH |
1301 | |
1302 | rc = misc_register(&vga_arb_device); | |
1303 | if (rc < 0) | |
1304 | pr_err("vgaarb: error %d registering device\n", rc); | |
1305 | ||
1306 | bus_register_notifier(&pci_bus_type, &pci_notifier); | |
1307 | ||
1308 | /* We add all pci devices satisfying vga class in the arbiter by | |
1309 | * default */ | |
1310 | pdev = NULL; | |
1311 | while ((pdev = | |
1312 | pci_get_subsys(PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, | |
1313 | PCI_ANY_ID, pdev)) != NULL) | |
1314 | vga_arbiter_add_pci_device(pdev); | |
1315 | ||
1316 | pr_info("vgaarb: loaded\n"); | |
3448a19d DA |
1317 | |
1318 | list_for_each_entry(vgadev, &vga_list, list) { | |
1319 | if (vgadev->bridge_has_one_vga) | |
1320 | pr_info("vgaarb: bridge control possible %s\n", pci_name(vgadev->pdev)); | |
1321 | else | |
1322 | pr_info("vgaarb: no bridge control possible %s\n", pci_name(vgadev->pdev)); | |
1323 | } | |
deb2d2ec BH |
1324 | return rc; |
1325 | } | |
1326 | subsys_initcall(vga_arb_device_init); |