X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fxen%2Fxenfb%2Fxenfb.c;fp=drivers%2Fxen%2Fxenfb%2Fxenfb.c;h=481aef672c42612c9300e852cefd07954d6078e5;hb=f05f9504c50ed069377d37f02f22e7a16b5921de;hp=0000000000000000000000000000000000000000;hpb=16c70f8c1b54b61c3b951b6fb220df250fe09b32;p=linux-2.6.git

diff --git a/drivers/xen/xenfb/xenfb.c b/drivers/xen/xenfb/xenfb.c
new file mode 100644
index 000000000..481aef672
--- /dev/null
+++ b/drivers/xen/xenfb/xenfb.c
@@ -0,0 +1,571 @@
+/*
+ * linux/drivers/video/xenfb.c -- Xen para-virtual frame buffer device
+ *
+ * Copyright (C) 2005-2006
+ *
+ *      Anthony Liguori <aliguori@us.ibm.com>
+ *
+ *  Based on linux/drivers/video/q40fb.c
+ *
+ *  This file is subject to the terms and conditions of the GNU General Public
+ *  License. See the file COPYING in the main directory of this archive for
+ *  more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/fb.h>
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include <linux/mm.h>
+#include <asm/hypervisor.h>
+#include <xen/evtchn.h>
+#include <xen/xenbus.h>
+#include <linux/xenfb.h>
+#include <linux/kthread.h>
+
+#define XENFB_WIDTH 800
+#define XENFB_HEIGHT 600
+#define XENFB_DEPTH 32
+
+static int xenfb_fps = 20;
+static unsigned long xenfb_mem_len = XENFB_WIDTH * XENFB_HEIGHT * XENFB_DEPTH / 8;
+
+struct xenfb_mapping
+{
+	struct list_head	next;
+	struct vm_area_struct	*vma;
+	atomic_t		map_refs;
+	int			faults;
+	struct xenfb_info	*info;
+};
+
+struct xenfb_info
+{
+	struct task_struct		*kthread;
+	wait_queue_head_t		wq;
+
+	unsigned char			*fb;
+	struct fb_fix_screeninfo	*fix;
+	struct fb_var_screeninfo	*var;
+	struct fb_info			*fb_info;
+	struct timer_list		refresh;
+	int				dirty;
+	int				y1, y2;
+	int				x1, x2;
+
+	struct semaphore		mm_lock;
+	int				nr_pages;
+	struct page			**pages;
+	struct list_head		mappings;
+
+	unsigned			evtchn;
+	int				irq;
+	struct xenfb_page		*page;
+	unsigned long 			*mfns;
+	u32				flags;
+};
+
+static void xenfb_do_update(struct xenfb_info *info,
+			    int x, int y, int w, int h)
+{
+	union xenfb_out_event event;
+	__u32 prod;
+
+	event.type = XENFB_TYPE_UPDATE;
+	event.update.x = x;
+	event.update.y = y;
+	event.update.width = w;
+	event.update.height = h;
+
+	prod = info->page->out_prod;
+	if (prod - info->page->out_cons == XENFB_OUT_RING_LEN)
+		return;		/* ring buffer full, event lost */
+	mb();			/* ensure ring space available */
+	XENFB_OUT_RING_REF(info->page, prod) = event;
+	wmb();			/* ensure ring contents visible */
+	info->page->out_prod = prod + 1;
+
+	notify_remote_via_evtchn(info->evtchn);
+}
+
+static int xenfb_queue_full(struct xenfb_info *info)
+{
+	__u32 cons, prod;
+
+	prod = info->page->out_prod;
+	cons = info->page->out_cons;
+	return prod - cons == XENFB_OUT_RING_LEN;
+}
+
+static void xenfb_update_screen(struct xenfb_info *info)
+{
+	int y1, y2, x1, x2;
+	struct list_head *item;
+	struct xenfb_mapping *map;
+
+	if (!(info->flags & XENFB_FLAG_UPDATE))
+		return;
+	if (xenfb_queue_full(info))
+		return;
+
+	y1 = info->y1;
+	y2 = info->y2;
+	x1 = info->x1;
+	x2 = info->x2;
+	info->y1 = info->y2 = info->x1 = info->x2 = 0;
+	down(&info->mm_lock);
+	list_for_each(item, &info->mappings) {
+		map = list_entry(item, struct xenfb_mapping, next);
+		if (!map->faults)
+			continue;
+		zap_page_range(map->vma, map->vma->vm_start,
+			       map->vma->vm_end - map->vma->vm_start, NULL);
+		map->faults = 0;
+	}
+	up(&info->mm_lock);
+
+	xenfb_do_update(info, x1, y1, x2 - x1, y2 - y1);
+}
+
+static int xenfb_thread(void *data)
+{
+	struct xenfb_info *info = data;
+
+	for (;;) {
+		if (kthread_should_stop())
+			break;
+		if (info->dirty) {
+			info->dirty = 0;
+			xenfb_update_screen(info);
+		}
+		wait_event_interruptible(info->wq,
+			kthread_should_stop() || info->dirty);
+	}
+	return 0;
+}
+
+static int xenfb_setcolreg(unsigned regno, unsigned red, unsigned green,
+			   unsigned blue, unsigned transp,
+			   struct fb_info *info)
+{
+	u32 v;
+
+	if (regno > info->cmap.len)
+		return 1;
+
+	red   >>= (16 - info->var.red.length);
+	green >>= (16 - info->var.green.length);
+	blue  >>= (16 - info->var.blue.length);
+
+	v = (red << info->var.red.offset) |
+	    (green << info->var.green.offset) |
+	    (blue << info->var.blue.offset);
+
+	switch (info->var.bits_per_pixel) {
+	case 16:
+	case 24:
+	case 32:
+		((u32 *)info->pseudo_palette)[regno] = v;
+		break;
+	}
+	
+	return 0;
+}
+
+static void xenfb_timer(unsigned long data)
+{
+	struct xenfb_info *info = (struct xenfb_info *)data;
+	info->dirty = 1;
+	wake_up(&info->wq);
+}
+
+static void xenfb_refresh(struct xenfb_info *info,
+			  int x1, int y1, int w, int h)
+{
+	int y2, x2;
+
+	y2 = y1 + h;
+	x2 = x1 + w;
+	if (info->y2 == 0) {
+		info->y1 = y1;
+		info->y2 = y2;
+	}
+	if (info->x2 == 0) {
+		info->x1 = x1;
+		info->x2 = x2;
+	}
+
+	if (info->y1 > y1)
+		info->y1 = y1;
+	if (info->y2 < y2)
+		info->y2 = y2;
+	if (info->x1 > x1)
+		info->x1 = x1;
+	if (info->x2 < x2)
+		info->x2 = x2;
+
+	if (timer_pending(&info->refresh))
+		return;
+
+	mod_timer(&info->refresh, jiffies + HZ/xenfb_fps);
+}
+
+static void xenfb_fillrect(struct fb_info *p, const struct fb_fillrect *rect)
+{
+	struct xenfb_info *info = p->par;
+
+	cfb_fillrect(p, rect);
+	xenfb_refresh(info, rect->dx, rect->dy, rect->width, rect->height);
+}
+
+static void xenfb_imageblit(struct fb_info *p, const struct fb_image *image)
+{
+	struct xenfb_info *info = p->par;
+
+	cfb_imageblit(p, image);
+	xenfb_refresh(info, image->dx, image->dy, image->width, image->height);
+}
+
+static void xenfb_copyarea(struct fb_info *p, const struct fb_copyarea *area)
+{
+	struct xenfb_info *info = p->par;
+
+	cfb_copyarea(p, area);
+	xenfb_refresh(info, area->dx, area->dy, area->width, area->height);
+}
+
+static void xenfb_vm_open(struct vm_area_struct *vma)
+{
+	struct xenfb_mapping *map = vma->vm_private_data;
+	atomic_inc(&map->map_refs);
+}
+
+static void xenfb_vm_close(struct vm_area_struct *vma)
+{
+	struct xenfb_mapping *map = vma->vm_private_data;
+	struct xenfb_info *info = map->info;
+
+	down(&info->mm_lock);
+	if (atomic_dec_and_test(&map->map_refs)) {
+		list_del(&map->next);
+		kfree(map);
+	}
+	up(&info->mm_lock);
+}
+
+static struct page *xenfb_vm_nopage(struct vm_area_struct *vma,
+				    unsigned long vaddr, int *type)
+{
+	struct xenfb_mapping *map = vma->vm_private_data;
+	struct xenfb_info *info = map->info;
+	int pgnr = (vaddr - vma->vm_start) >> PAGE_SHIFT;
+	struct page *page;
+	int y1, y2;
+
+	if (pgnr >= info->nr_pages)
+		return NOPAGE_SIGBUS;
+
+	down(&info->mm_lock);
+	page = info->pages[pgnr];
+	get_page(page);
+	map->faults++;
+
+	y1 = pgnr * PAGE_SIZE / info->fix->line_length;
+	y2 = (pgnr * PAGE_SIZE + PAGE_SIZE - 1) / info->fix->line_length;
+	if (y2 > info->var->yres)
+		y2 = info->var->yres;
+	xenfb_refresh(info, 0, y1, info->var->xres, y2 - y1);
+	up(&info->mm_lock);
+
+	if (type)
+		*type = VM_FAULT_MINOR;
+
+	return page;
+}
+
+static struct vm_operations_struct xenfb_vm_ops = {
+	.open	= xenfb_vm_open,
+	.close	= xenfb_vm_close,
+	.nopage	= xenfb_vm_nopage,
+};
+
+static int xenfb_mmap(struct fb_info *fb_info, struct vm_area_struct *vma)
+{
+	struct xenfb_info *info = fb_info->par;
+	struct xenfb_mapping *map;
+	int ret;
+	int map_pages;
+
+	down(&info->mm_lock);
+
+	ret = -EINVAL;
+	if (!(vma->vm_flags & VM_WRITE))
+		goto out;
+	if (!(vma->vm_flags & VM_SHARED))
+		goto out;
+	if (vma->vm_pgoff != 0)
+		goto out;
+
+	map_pages = (vma->vm_end - vma->vm_start + PAGE_SIZE-1) >> PAGE_SHIFT;
+	if (map_pages > info->nr_pages)
+		goto out;
+
+	ret = -ENOMEM;
+	map = kmalloc(sizeof(*map), GFP_KERNEL);
+	if (map == NULL)
+		goto out;
+	memset(map, 0, sizeof(*map));
+
+	map->vma = vma;
+	map->faults = 0;
+	map->info = info;
+	atomic_set(&map->map_refs, 1);
+	list_add(&map->next, &info->mappings);
+	vma->vm_ops = &xenfb_vm_ops;
+	vma->vm_flags |= (VM_DONTEXPAND | VM_RESERVED);
+	vma->vm_private_data = map;
+	ret = 0;
+
+ out:
+	up(&info->mm_lock);
+	return ret;
+}
+
+static struct fb_ops xenfb_fb_ops = {
+	.owner		= THIS_MODULE,
+	.fb_setcolreg	= xenfb_setcolreg,
+	.fb_fillrect	= xenfb_fillrect,
+	.fb_copyarea	= xenfb_copyarea,
+	.fb_imageblit	= xenfb_imageblit,
+	.fb_mmap	= xenfb_mmap,
+};
+
+static irqreturn_t xenfb_event_handler(int rq, void *dev_id,
+				       struct pt_regs *regs)
+{
+	struct xenfb_info *info = dev_id;
+	__u32 cons, prod;
+
+	prod = info->page->in_prod;
+	rmb();			/* ensure we see ring contents up to prod */
+	for (cons = info->page->in_cons; cons != prod; cons++) {
+		union xenfb_in_event *event;
+		event = &XENFB_IN_RING_REF(info->page, cons);
+
+		switch (event->type) {
+		case XENFB_TYPE_SET_EVENTS:
+			info->flags = event->set_events.flags;
+			break;
+		}
+	}
+	mb();			/* ensure we're done with ring contents */
+	info->page->in_cons = cons;
+	notify_remote_via_evtchn(info->evtchn);
+
+	return IRQ_HANDLED;
+}
+
+static unsigned long vmalloc_to_mfn(void *address)
+{
+	return pfn_to_mfn(vmalloc_to_pfn(address));
+	//return arbitrary_virt_to_machine(address) >> PAGE_SHIFT;
+}
+
+static struct xenfb_info *xenfb_info;
+
+static int __init xenfb_probe(void)
+{
+	struct xenfb_info *info;
+	int i, ret;
+	struct fb_info *fb_info;
+	struct evtchn_alloc_unbound alloc_unbound;
+	struct evtchn_close close;
+	struct xenbus_transaction xbt;
+
+        /* Nothing to do if running in dom0. */
+        if (is_initial_xendomain())
+		return -ENODEV;
+#if 1
+        /* if we're not set up to use graphics mode, then don't initialize */
+	if (xenbus_scanf(XBT_NIL, "console", "use_graphics", "%d", &ret) < 0)
+		return -ENODEV;
+	if (ret == 0)
+		return -ENODEV;
+#endif
+
+	info = kmalloc(sizeof(*info), GFP_KERNEL);
+	if (info == NULL)
+		return -ENOMEM;
+	memset(info, 0, sizeof(*info));
+
+	INIT_LIST_HEAD(&info->mappings);
+
+	info->fb = vmalloc(xenfb_mem_len);
+	if (info->fb == NULL)
+		goto error;
+	memset(info->fb, 0, xenfb_mem_len);
+	info->nr_pages = (xenfb_mem_len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+	info->pages = kmalloc(sizeof(struct page*)*info->nr_pages, GFP_KERNEL);
+	if (info->pages == NULL)
+		goto error_vfree;
+	for (i = 0; i < info->nr_pages; i++)
+		info->pages[i] = vmalloc_to_page(info->fb + i * PAGE_SIZE);
+
+	fb_info = framebuffer_alloc(sizeof(u32) * 256, NULL);
+	// FIXME sizeof(struct xenfb_info)
+	if (fb_info == NULL)
+		goto error_kfree;
+
+	info->mfns = vmalloc(sizeof(unsigned long) * info->nr_pages);
+	/* set up shared page */
+	info->page = (void *)__get_free_page(GFP_KERNEL);
+	if (!info->page)
+		goto error_kfree;
+	/* set up event channel */
+	alloc_unbound.dom = DOMID_SELF;
+	alloc_unbound.remote_dom = 0;
+	ret = HYPERVISOR_event_channel_op(EVTCHNOP_alloc_unbound,
+					  &alloc_unbound);
+	if (ret)
+		goto error_freep;
+	info->evtchn = alloc_unbound.port;
+
+	for (i = 0; i < info->nr_pages; i++)
+		info->mfns[i] = vmalloc_to_mfn(info->fb + i * PAGE_SIZE);
+	info->page->pd[0] = vmalloc_to_mfn(info->mfns);
+	info->page->pd[1] = 0;
+	info->page->width = XENFB_WIDTH;
+	info->page->height = XENFB_HEIGHT;
+	info->page->depth = XENFB_DEPTH;
+	info->page->line_length = (info->page->depth / 8) * info->page->width;
+	info->page->mem_length = xenfb_mem_len;
+	info->page->in_cons = info->page->in_prod = 0;
+	info->page->out_cons = info->page->out_prod = 0;
+
+	ret = bind_evtchn_to_irqhandler(info->evtchn, xenfb_event_handler,
+					0, "xenfb", info);
+	if (ret < 0) {
+		close.port = info->evtchn;
+		HYPERVISOR_event_channel_op(EVTCHNOP_close, &close);
+		goto error_freep;
+	}
+
+	info->irq = ret;
+	xenfb_info = info;
+
+	fb_info->pseudo_palette = fb_info->par;
+	fb_info->par = info;
+	fb_info->screen_base = info->fb;
+
+	memset(&fb_info->var, 0, sizeof(fb_info->var));
+	memset(&fb_info->fix, 0, sizeof(fb_info->fix));
+
+	fb_info->fbops = &xenfb_fb_ops;
+	fb_info->var.xres_virtual = fb_info->var.xres = info->page->width;
+	fb_info->var.yres_virtual = fb_info->var.yres = info->page->height;
+	fb_info->var.bits_per_pixel = info->page->depth;
+
+	fb_info->var.red = (struct fb_bitfield){16, 8, 0};
+	fb_info->var.green = (struct fb_bitfield){8, 8, 0};
+	fb_info->var.blue = (struct fb_bitfield){0, 8, 0};
+
+	fb_info->var.activate = FB_ACTIVATE_NOW;
+	fb_info->var.height = -1;
+	fb_info->var.width = -1;
+	fb_info->var.vmode = FB_VMODE_NONINTERLACED;
+
+	fb_info->fix.visual = FB_VISUAL_TRUECOLOR;
+	fb_info->fix.line_length = info->page->line_length;
+	fb_info->fix.smem_start = 0;
+	fb_info->fix.smem_len = xenfb_mem_len;
+	strcpy(fb_info->fix.id, "xen");
+	fb_info->fix.type = FB_TYPE_PACKED_PIXELS;
+	fb_info->fix.accel = FB_ACCEL_NONE;
+
+	fb_info->flags = FBINFO_FLAG_DEFAULT;
+
+	fb_alloc_cmap(&fb_info->cmap, 256, 0);
+
+	info->fb_info = fb_info;
+	info->fix = &fb_info->fix;
+	info->var = &fb_info->var;
+
+	init_MUTEX(&info->mm_lock);
+	init_waitqueue_head(&info->wq);
+	init_timer(&info->refresh);
+	info->refresh.function = xenfb_timer;
+	info->refresh.data = (unsigned long)info;
+
+	info->kthread = kthread_run(xenfb_thread, info, "xenfb thread");
+	if (IS_ERR(info->kthread))
+		goto error_unbind;
+
+	ret = register_framebuffer(fb_info);
+	if (ret)
+		goto error_unbind;
+
+ again:
+	ret = xenbus_transaction_start(&xbt);
+	if (ret)
+		goto error_unreg;
+	ret = xenbus_printf(xbt, "vfb", "page-ref", "%lu",
+			    virt_to_mfn(info->page));
+	// FIXME grant tables?
+	if (ret)
+		goto error_xenbus;
+	ret = xenbus_printf(xbt, "vfb", "event-channel", "%u",
+			    info->evtchn);
+	if (ret)
+		goto error_xenbus;
+	ret = xenbus_transaction_end(xbt, 0);
+	if (ret) {
+		if (ret == -EAGAIN)
+			goto again;
+		goto error_unreg;
+	}
+
+	return 0;
+
+ error_xenbus:
+	xenbus_transaction_end(xbt, 1);
+ error_unreg:
+	unregister_framebuffer(fb_info);
+ error_unbind:
+	unbind_from_irqhandler(info->irq, info);
+	// FIXME do we have to stop info->kthread?
+ error_freep:
+	free_page((unsigned long)info->page);
+ error_kfree:
+	kfree(info->pages);
+ error_vfree:
+	vfree(info->fb);
+ error:
+	kfree(info);
+	xenfb_info = NULL;
+
+	return -ENODEV;
+}
+
+static int __init xenfb_init(void)
+{
+	return xenfb_probe();
+}
+
+static void __exit xenfb_cleanup(void)
+{
+	struct xenfb_info *info = xenfb_info;
+
+	unregister_framebuffer(info->fb_info);
+	unbind_from_irqhandler(info->irq, info);
+	free_page((unsigned long)info->page);
+	kfree(info->pages);
+	vfree(info->fb);
+	kfree(info);
+	xenfb_info = NULL;
+}
+
+module_init(xenfb_init);
+module_exit(xenfb_cleanup);
+
+MODULE_LICENSE("GPL");