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21#include <linux/console.h>
22#include <linux/kernel.h>
23#include <linux/errno.h>
24#include <linux/fb.h>
25#include <linux/module.h>
26#include <linux/vmalloc.h>
27#include <linux/mm.h>
28#include <asm/xen/hypervisor.h>
29#include <xen/events.h>
30#include <xen/page.h>
31#include <xen/interface/io/fbif.h>
32#include <xen/interface/io/protocols.h>
33#include <xen/xenbus.h>
34
35struct xenfb_info {
36 unsigned char *fb;
37 struct fb_info *fb_info;
38 int x1, y1, x2, y2;
39
40 spinlock_t dirty_lock;
41 int nr_pages;
42 int irq;
43 struct xenfb_page *page;
44 unsigned long *mfns;
45 int update_wanted;
46 int feature_resize;
47 struct xenfb_resize resize;
48 int resize_dpy;
49 spinlock_t resize_lock;
50
51 struct xenbus_device *xbdev;
52};
53
54#define XENFB_DEFAULT_FB_LEN (XENFB_WIDTH * XENFB_HEIGHT * XENFB_DEPTH / 8)
55
56enum { KPARAM_MEM, KPARAM_WIDTH, KPARAM_HEIGHT, KPARAM_CNT };
57static int video[KPARAM_CNT] = { 2, XENFB_WIDTH, XENFB_HEIGHT };
58module_param_array(video, int, NULL, 0);
59MODULE_PARM_DESC(video,
60 "Video memory size in MB, width, height in pixels (default 2,800,600)");
61
62static void xenfb_make_preferred_console(void);
63static int xenfb_remove(struct xenbus_device *);
64static void xenfb_init_shared_page(struct xenfb_info *, struct fb_info *);
65static int xenfb_connect_backend(struct xenbus_device *, struct xenfb_info *);
66static void xenfb_disconnect_backend(struct xenfb_info *);
67
68static void xenfb_send_event(struct xenfb_info *info,
69 union xenfb_out_event *event)
70{
71 u32 prod;
72
73 prod = info->page->out_prod;
74
75 mb();
76 XENFB_OUT_RING_REF(info->page, prod) = *event;
77 wmb();
78 info->page->out_prod = prod + 1;
79
80 notify_remote_via_irq(info->irq);
81}
82
83static void xenfb_do_update(struct xenfb_info *info,
84 int x, int y, int w, int h)
85{
86 union xenfb_out_event event;
87
88 memset(&event, 0, sizeof(event));
89 event.type = XENFB_TYPE_UPDATE;
90 event.update.x = x;
91 event.update.y = y;
92 event.update.width = w;
93 event.update.height = h;
94
95
96 xenfb_send_event(info, &event);
97}
98
99static void xenfb_do_resize(struct xenfb_info *info)
100{
101 union xenfb_out_event event;
102
103 memset(&event, 0, sizeof(event));
104 event.resize = info->resize;
105
106
107 xenfb_send_event(info, &event);
108}
109
110static int xenfb_queue_full(struct xenfb_info *info)
111{
112 u32 cons, prod;
113
114 prod = info->page->out_prod;
115 cons = info->page->out_cons;
116 return prod - cons == XENFB_OUT_RING_LEN;
117}
118
119static void xenfb_handle_resize_dpy(struct xenfb_info *info)
120{
121 unsigned long flags;
122
123 spin_lock_irqsave(&info->resize_lock, flags);
124 if (info->resize_dpy) {
125 if (!xenfb_queue_full(info)) {
126 info->resize_dpy = 0;
127 xenfb_do_resize(info);
128 }
129 }
130 spin_unlock_irqrestore(&info->resize_lock, flags);
131}
132
133static void xenfb_refresh(struct xenfb_info *info,
134 int x1, int y1, int w, int h)
135{
136 unsigned long flags;
137 int x2 = x1 + w - 1;
138 int y2 = y1 + h - 1;
139
140 xenfb_handle_resize_dpy(info);
141
142 if (!info->update_wanted)
143 return;
144
145 spin_lock_irqsave(&info->dirty_lock, flags);
146
147
148 if (info->y1 < y1)
149 y1 = info->y1;
150 if (info->y2 > y2)
151 y2 = info->y2;
152 if (info->x1 < x1)
153 x1 = info->x1;
154 if (info->x2 > x2)
155 x2 = info->x2;
156
157 if (xenfb_queue_full(info)) {
158
159 info->x1 = x1;
160 info->x2 = x2;
161 info->y1 = y1;
162 info->y2 = y2;
163 spin_unlock_irqrestore(&info->dirty_lock, flags);
164 return;
165 }
166
167
168 info->x1 = info->y1 = INT_MAX;
169 info->x2 = info->y2 = 0;
170
171 spin_unlock_irqrestore(&info->dirty_lock, flags);
172
173 if (x1 <= x2 && y1 <= y2)
174 xenfb_do_update(info, x1, y1, x2 - x1 + 1, y2 - y1 + 1);
175}
176
177static void xenfb_deferred_io(struct fb_info *fb_info,
178 struct list_head *pagelist)
179{
180 struct xenfb_info *info = fb_info->par;
181 struct page *page;
182 unsigned long beg, end;
183 int y1, y2, miny, maxy;
184
185 miny = INT_MAX;
186 maxy = 0;
187 list_for_each_entry(page, pagelist, lru) {
188 beg = page->index << PAGE_SHIFT;
189 end = beg + PAGE_SIZE - 1;
190 y1 = beg / fb_info->fix.line_length;
191 y2 = end / fb_info->fix.line_length;
192 if (y2 >= fb_info->var.yres)
193 y2 = fb_info->var.yres - 1;
194 if (miny > y1)
195 miny = y1;
196 if (maxy < y2)
197 maxy = y2;
198 }
199 xenfb_refresh(info, 0, miny, fb_info->var.xres, maxy - miny + 1);
200}
201
202static struct fb_deferred_io xenfb_defio = {
203 .delay = HZ / 20,
204 .deferred_io = xenfb_deferred_io,
205};
206
207static int xenfb_setcolreg(unsigned regno, unsigned red, unsigned green,
208 unsigned blue, unsigned transp,
209 struct fb_info *info)
210{
211 u32 v;
212
213 if (regno > info->cmap.len)
214 return 1;
215
216#define CNVT_TOHW(val, width) ((((val)<<(width))+0x7FFF-(val))>>16)
217 red = CNVT_TOHW(red, info->var.red.length);
218 green = CNVT_TOHW(green, info->var.green.length);
219 blue = CNVT_TOHW(blue, info->var.blue.length);
220 transp = CNVT_TOHW(transp, info->var.transp.length);
221#undef CNVT_TOHW
222
223 v = (red << info->var.red.offset) |
224 (green << info->var.green.offset) |
225 (blue << info->var.blue.offset);
226
227 switch (info->var.bits_per_pixel) {
228 case 16:
229 case 24:
230 case 32:
231 ((u32 *)info->pseudo_palette)[regno] = v;
232 break;
233 }
234
235 return 0;
236}
237
238static void xenfb_fillrect(struct fb_info *p, const struct fb_fillrect *rect)
239{
240 struct xenfb_info *info = p->par;
241
242 sys_fillrect(p, rect);
243 xenfb_refresh(info, rect->dx, rect->dy, rect->width, rect->height);
244}
245
246static void xenfb_imageblit(struct fb_info *p, const struct fb_image *image)
247{
248 struct xenfb_info *info = p->par;
249
250 sys_imageblit(p, image);
251 xenfb_refresh(info, image->dx, image->dy, image->width, image->height);
252}
253
254static void xenfb_copyarea(struct fb_info *p, const struct fb_copyarea *area)
255{
256 struct xenfb_info *info = p->par;
257
258 sys_copyarea(p, area);
259 xenfb_refresh(info, area->dx, area->dy, area->width, area->height);
260}
261
262static ssize_t xenfb_write(struct fb_info *p, const char __user *buf,
263 size_t count, loff_t *ppos)
264{
265 struct xenfb_info *info = p->par;
266 ssize_t res;
267
268 res = fb_sys_write(p, buf, count, ppos);
269 xenfb_refresh(info, 0, 0, info->page->width, info->page->height);
270 return res;
271}
272
273static int
274xenfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
275{
276 struct xenfb_info *xenfb_info;
277 int required_mem_len;
278
279 xenfb_info = info->par;
280
281 if (!xenfb_info->feature_resize) {
282 if (var->xres == video[KPARAM_WIDTH] &&
283 var->yres == video[KPARAM_HEIGHT] &&
284 var->bits_per_pixel == xenfb_info->page->depth) {
285 return 0;
286 }
287 return -EINVAL;
288 }
289
290
291 if (var->xres > video[KPARAM_WIDTH] || var->yres > video[KPARAM_HEIGHT])
292 return -EINVAL;
293
294 required_mem_len = var->xres * var->yres * xenfb_info->page->depth / 8;
295 if (var->bits_per_pixel == xenfb_info->page->depth &&
296 var->xres <= info->fix.line_length / (XENFB_DEPTH / 8) &&
297 required_mem_len <= info->fix.smem_len) {
298 var->xres_virtual = var->xres;
299 var->yres_virtual = var->yres;
300 return 0;
301 }
302 return -EINVAL;
303}
304
305static int xenfb_set_par(struct fb_info *info)
306{
307 struct xenfb_info *xenfb_info;
308 unsigned long flags;
309
310 xenfb_info = info->par;
311
312 spin_lock_irqsave(&xenfb_info->resize_lock, flags);
313 xenfb_info->resize.type = XENFB_TYPE_RESIZE;
314 xenfb_info->resize.width = info->var.xres;
315 xenfb_info->resize.height = info->var.yres;
316 xenfb_info->resize.stride = info->fix.line_length;
317 xenfb_info->resize.depth = info->var.bits_per_pixel;
318 xenfb_info->resize.offset = 0;
319 xenfb_info->resize_dpy = 1;
320 spin_unlock_irqrestore(&xenfb_info->resize_lock, flags);
321 return 0;
322}
323
324static struct fb_ops xenfb_fb_ops = {
325 .owner = THIS_MODULE,
326 .fb_read = fb_sys_read,
327 .fb_write = xenfb_write,
328 .fb_setcolreg = xenfb_setcolreg,
329 .fb_fillrect = xenfb_fillrect,
330 .fb_copyarea = xenfb_copyarea,
331 .fb_imageblit = xenfb_imageblit,
332 .fb_check_var = xenfb_check_var,
333 .fb_set_par = xenfb_set_par,
334};
335
336static irqreturn_t xenfb_event_handler(int rq, void *dev_id)
337{
338
339
340
341
342
343 struct xenfb_info *info = dev_id;
344 struct xenfb_page *page = info->page;
345
346 if (page->in_cons != page->in_prod) {
347 info->page->in_cons = info->page->in_prod;
348 notify_remote_via_irq(info->irq);
349 }
350
351
352 xenfb_refresh(info, INT_MAX, INT_MAX, -INT_MAX, -INT_MAX);
353
354 return IRQ_HANDLED;
355}
356
357static int __devinit xenfb_probe(struct xenbus_device *dev,
358 const struct xenbus_device_id *id)
359{
360 struct xenfb_info *info;
361 struct fb_info *fb_info;
362 int fb_size;
363 int val;
364 int ret;
365
366 info = kzalloc(sizeof(*info), GFP_KERNEL);
367 if (info == NULL) {
368 xenbus_dev_fatal(dev, -ENOMEM, "allocating info structure");
369 return -ENOMEM;
370 }
371
372
373 if (xenbus_scanf(XBT_NIL, dev->otherend, "videoram", "%d", &val) == 1) {
374 if (val < video[KPARAM_MEM])
375 video[KPARAM_MEM] = val;
376 }
377
378
379 fb_size = video[KPARAM_MEM] * 1024 * 1024;
380 if (video[KPARAM_WIDTH] * video[KPARAM_HEIGHT] * XENFB_DEPTH / 8
381 > fb_size) {
382 video[KPARAM_WIDTH] = XENFB_WIDTH;
383 video[KPARAM_HEIGHT] = XENFB_HEIGHT;
384 fb_size = XENFB_DEFAULT_FB_LEN;
385 }
386
387 dev_set_drvdata(&dev->dev, info);
388 info->xbdev = dev;
389 info->irq = -1;
390 info->x1 = info->y1 = INT_MAX;
391 spin_lock_init(&info->dirty_lock);
392 spin_lock_init(&info->resize_lock);
393
394 info->fb = vmalloc(fb_size);
395 if (info->fb == NULL)
396 goto error_nomem;
397 memset(info->fb, 0, fb_size);
398
399 info->nr_pages = (fb_size + PAGE_SIZE - 1) >> PAGE_SHIFT;
400
401 info->mfns = vmalloc(sizeof(unsigned long) * info->nr_pages);
402 if (!info->mfns)
403 goto error_nomem;
404
405
406 info->page = (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
407 if (!info->page)
408 goto error_nomem;
409
410
411 fb_info = framebuffer_alloc(sizeof(u32) * 256, NULL);
412 if (fb_info == NULL)
413 goto error_nomem;
414
415
416 fb_info->pseudo_palette = fb_info->par;
417 fb_info->par = info;
418
419 fb_info->screen_base = info->fb;
420
421 fb_info->fbops = &xenfb_fb_ops;
422 fb_info->var.xres_virtual = fb_info->var.xres = video[KPARAM_WIDTH];
423 fb_info->var.yres_virtual = fb_info->var.yres = video[KPARAM_HEIGHT];
424 fb_info->var.bits_per_pixel = XENFB_DEPTH;
425
426 fb_info->var.red = (struct fb_bitfield){16, 8, 0};
427 fb_info->var.green = (struct fb_bitfield){8, 8, 0};
428 fb_info->var.blue = (struct fb_bitfield){0, 8, 0};
429
430 fb_info->var.activate = FB_ACTIVATE_NOW;
431 fb_info->var.height = -1;
432 fb_info->var.width = -1;
433 fb_info->var.vmode = FB_VMODE_NONINTERLACED;
434
435 fb_info->fix.visual = FB_VISUAL_TRUECOLOR;
436 fb_info->fix.line_length = fb_info->var.xres * XENFB_DEPTH / 8;
437 fb_info->fix.smem_start = 0;
438 fb_info->fix.smem_len = fb_size;
439 strcpy(fb_info->fix.id, "xen");
440 fb_info->fix.type = FB_TYPE_PACKED_PIXELS;
441 fb_info->fix.accel = FB_ACCEL_NONE;
442
443 fb_info->flags = FBINFO_FLAG_DEFAULT;
444
445 ret = fb_alloc_cmap(&fb_info->cmap, 256, 0);
446 if (ret < 0) {
447 framebuffer_release(fb_info);
448 xenbus_dev_fatal(dev, ret, "fb_alloc_cmap");
449 goto error;
450 }
451
452 fb_info->fbdefio = &xenfb_defio;
453 fb_deferred_io_init(fb_info);
454
455 xenfb_init_shared_page(info, fb_info);
456
457 ret = xenfb_connect_backend(dev, info);
458 if (ret < 0)
459 goto error;
460
461 ret = register_framebuffer(fb_info);
462 if (ret) {
463 fb_deferred_io_cleanup(fb_info);
464 fb_dealloc_cmap(&fb_info->cmap);
465 framebuffer_release(fb_info);
466 xenbus_dev_fatal(dev, ret, "register_framebuffer");
467 goto error;
468 }
469 info->fb_info = fb_info;
470
471 xenfb_make_preferred_console();
472 return 0;
473
474 error_nomem:
475 ret = -ENOMEM;
476 xenbus_dev_fatal(dev, ret, "allocating device memory");
477 error:
478 xenfb_remove(dev);
479 return ret;
480}
481
482static __devinit void
483xenfb_make_preferred_console(void)
484{
485 struct console *c;
486
487 if (console_set_on_cmdline)
488 return;
489
490 acquire_console_sem();
491 for (c = console_drivers; c; c = c->next) {
492 if (!strcmp(c->name, "tty") && c->index == 0)
493 break;
494 }
495 release_console_sem();
496 if (c) {
497 unregister_console(c);
498 c->flags |= CON_CONSDEV;
499 c->flags &= ~CON_PRINTBUFFER;
500 register_console(c);
501 }
502}
503
504static int xenfb_resume(struct xenbus_device *dev)
505{
506 struct xenfb_info *info = dev_get_drvdata(&dev->dev);
507
508 xenfb_disconnect_backend(info);
509 xenfb_init_shared_page(info, info->fb_info);
510 return xenfb_connect_backend(dev, info);
511}
512
513static int xenfb_remove(struct xenbus_device *dev)
514{
515 struct xenfb_info *info = dev_get_drvdata(&dev->dev);
516
517 xenfb_disconnect_backend(info);
518 if (info->fb_info) {
519 fb_deferred_io_cleanup(info->fb_info);
520 unregister_framebuffer(info->fb_info);
521 fb_dealloc_cmap(&info->fb_info->cmap);
522 framebuffer_release(info->fb_info);
523 }
524 free_page((unsigned long)info->page);
525 vfree(info->mfns);
526 vfree(info->fb);
527 kfree(info);
528
529 return 0;
530}
531
532static unsigned long vmalloc_to_mfn(void *address)
533{
534 return pfn_to_mfn(vmalloc_to_pfn(address));
535}
536
537static void xenfb_init_shared_page(struct xenfb_info *info,
538 struct fb_info *fb_info)
539{
540 int i;
541 int epd = PAGE_SIZE / sizeof(info->mfns[0]);
542
543 for (i = 0; i < info->nr_pages; i++)
544 info->mfns[i] = vmalloc_to_mfn(info->fb + i * PAGE_SIZE);
545
546 for (i = 0; i * epd < info->nr_pages; i++)
547 info->page->pd[i] = vmalloc_to_mfn(&info->mfns[i * epd]);
548
549 info->page->width = fb_info->var.xres;
550 info->page->height = fb_info->var.yres;
551 info->page->depth = fb_info->var.bits_per_pixel;
552 info->page->line_length = fb_info->fix.line_length;
553 info->page->mem_length = fb_info->fix.smem_len;
554 info->page->in_cons = info->page->in_prod = 0;
555 info->page->out_cons = info->page->out_prod = 0;
556}
557
558static int xenfb_connect_backend(struct xenbus_device *dev,
559 struct xenfb_info *info)
560{
561 int ret, evtchn;
562 struct xenbus_transaction xbt;
563
564 ret = xenbus_alloc_evtchn(dev, &evtchn);
565 if (ret)
566 return ret;
567 ret = bind_evtchn_to_irqhandler(evtchn, xenfb_event_handler,
568 0, dev->devicetype, info);
569 if (ret < 0) {
570 xenbus_free_evtchn(dev, evtchn);
571 xenbus_dev_fatal(dev, ret, "bind_evtchn_to_irqhandler");
572 return ret;
573 }
574 info->irq = ret;
575
576 again:
577 ret = xenbus_transaction_start(&xbt);
578 if (ret) {
579 xenbus_dev_fatal(dev, ret, "starting transaction");
580 return ret;
581 }
582 ret = xenbus_printf(xbt, dev->nodename, "page-ref", "%lu",
583 virt_to_mfn(info->page));
584 if (ret)
585 goto error_xenbus;
586 ret = xenbus_printf(xbt, dev->nodename, "event-channel", "%u",
587 evtchn);
588 if (ret)
589 goto error_xenbus;
590 ret = xenbus_printf(xbt, dev->nodename, "protocol", "%s",
591 XEN_IO_PROTO_ABI_NATIVE);
592 if (ret)
593 goto error_xenbus;
594 ret = xenbus_printf(xbt, dev->nodename, "feature-update", "1");
595 if (ret)
596 goto error_xenbus;
597 ret = xenbus_transaction_end(xbt, 0);
598 if (ret) {
599 if (ret == -EAGAIN)
600 goto again;
601 xenbus_dev_fatal(dev, ret, "completing transaction");
602 return ret;
603 }
604
605 xenbus_switch_state(dev, XenbusStateInitialised);
606 return 0;
607
608 error_xenbus:
609 xenbus_transaction_end(xbt, 1);
610 xenbus_dev_fatal(dev, ret, "writing xenstore");
611 return ret;
612}
613
614static void xenfb_disconnect_backend(struct xenfb_info *info)
615{
616 if (info->irq >= 0)
617 unbind_from_irqhandler(info->irq, info);
618 info->irq = -1;
619}
620
621static void xenfb_backend_changed(struct xenbus_device *dev,
622 enum xenbus_state backend_state)
623{
624 struct xenfb_info *info = dev_get_drvdata(&dev->dev);
625 int val;
626
627 switch (backend_state) {
628 case XenbusStateInitialising:
629 case XenbusStateInitialised:
630 case XenbusStateUnknown:
631 case XenbusStateClosed:
632 break;
633
634 case XenbusStateInitWait:
635InitWait:
636 xenbus_switch_state(dev, XenbusStateConnected);
637 break;
638
639 case XenbusStateConnected:
640
641
642
643
644
645 if (dev->state != XenbusStateConnected)
646 goto InitWait;
647
648 if (xenbus_scanf(XBT_NIL, info->xbdev->otherend,
649 "request-update", "%d", &val) < 0)
650 val = 0;
651 if (val)
652 info->update_wanted = 1;
653
654 if (xenbus_scanf(XBT_NIL, dev->otherend,
655 "feature-resize", "%d", &val) < 0)
656 val = 0;
657 info->feature_resize = val;
658 break;
659
660 case XenbusStateClosing:
661 xenbus_frontend_closed(dev);
662 break;
663 }
664}
665
666static struct xenbus_device_id xenfb_ids[] = {
667 { "vfb" },
668 { "" }
669};
670
671static struct xenbus_driver xenfb_driver = {
672 .name = "vfb",
673 .owner = THIS_MODULE,
674 .ids = xenfb_ids,
675 .probe = xenfb_probe,
676 .remove = xenfb_remove,
677 .resume = xenfb_resume,
678 .otherend_changed = xenfb_backend_changed,
679};
680
681static int __init xenfb_init(void)
682{
683 if (!xen_domain())
684 return -ENODEV;
685
686
687 if (xen_initial_domain())
688 return -ENODEV;
689
690 return xenbus_register_frontend(&xenfb_driver);
691}
692
693static void __exit xenfb_cleanup(void)
694{
695 xenbus_unregister_driver(&xenfb_driver);
696}
697
698module_init(xenfb_init);
699module_exit(xenfb_cleanup);
700
701MODULE_DESCRIPTION("Xen virtual framebuffer device frontend");
702MODULE_LICENSE("GPL");
703MODULE_ALIAS("xen:vfb");
704
