v4.19.13 snapshot.
diff --git a/drivers/video/fbdev/xen-fbfront.c b/drivers/video/fbdev/xen-fbfront.c
new file mode 100644
index 0000000..6a4bbc9
--- /dev/null
+++ b/drivers/video/fbdev/xen-fbfront.c
@@ -0,0 +1,725 @@
+/*
+ * Xen para-virtual frame buffer device
+ *
+ * Copyright (C) 2005-2006 Anthony Liguori <aliguori@us.ibm.com>
+ * Copyright (C) 2006-2008 Red Hat, Inc., Markus Armbruster <armbru@redhat.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.
+ */
+
+/*
+ * TODO:
+ *
+ * Switch to grant tables when they become capable of dealing with the
+ * frame buffer.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/console.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/fb.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/mm.h>
+
+#include <asm/xen/hypervisor.h>
+
+#include <xen/xen.h>
+#include <xen/events.h>
+#include <xen/page.h>
+#include <xen/interface/io/fbif.h>
+#include <xen/interface/io/protocols.h>
+#include <xen/xenbus.h>
+#include <xen/platform_pci.h>
+
+struct xenfb_info {
+ unsigned char *fb;
+ struct fb_info *fb_info;
+ int x1, y1, x2, y2; /* dirty rectangle,
+ protected by dirty_lock */
+ spinlock_t dirty_lock;
+ int nr_pages;
+ int irq;
+ struct xenfb_page *page;
+ unsigned long *gfns;
+ int update_wanted; /* XENFB_TYPE_UPDATE wanted */
+ int feature_resize; /* XENFB_TYPE_RESIZE ok */
+ struct xenfb_resize resize; /* protected by resize_lock */
+ int resize_dpy; /* ditto */
+ spinlock_t resize_lock;
+
+ struct xenbus_device *xbdev;
+};
+
+#define XENFB_DEFAULT_FB_LEN (XENFB_WIDTH * XENFB_HEIGHT * XENFB_DEPTH / 8)
+
+enum { KPARAM_MEM, KPARAM_WIDTH, KPARAM_HEIGHT, KPARAM_CNT };
+static int video[KPARAM_CNT] = { 2, XENFB_WIDTH, XENFB_HEIGHT };
+module_param_array(video, int, NULL, 0);
+MODULE_PARM_DESC(video,
+ "Video memory size in MB, width, height in pixels (default 2,800,600)");
+
+static void xenfb_make_preferred_console(void);
+static int xenfb_remove(struct xenbus_device *);
+static void xenfb_init_shared_page(struct xenfb_info *, struct fb_info *);
+static int xenfb_connect_backend(struct xenbus_device *, struct xenfb_info *);
+static void xenfb_disconnect_backend(struct xenfb_info *);
+
+static void xenfb_send_event(struct xenfb_info *info,
+ union xenfb_out_event *event)
+{
+ u32 prod;
+
+ prod = info->page->out_prod;
+ /* caller ensures !xenfb_queue_full() */
+ 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_irq(info->irq);
+}
+
+static void xenfb_do_update(struct xenfb_info *info,
+ int x, int y, int w, int h)
+{
+ union xenfb_out_event event;
+
+ memset(&event, 0, sizeof(event));
+ event.type = XENFB_TYPE_UPDATE;
+ event.update.x = x;
+ event.update.y = y;
+ event.update.width = w;
+ event.update.height = h;
+
+ /* caller ensures !xenfb_queue_full() */
+ xenfb_send_event(info, &event);
+}
+
+static void xenfb_do_resize(struct xenfb_info *info)
+{
+ union xenfb_out_event event;
+
+ memset(&event, 0, sizeof(event));
+ event.resize = info->resize;
+
+ /* caller ensures !xenfb_queue_full() */
+ xenfb_send_event(info, &event);
+}
+
+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_handle_resize_dpy(struct xenfb_info *info)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&info->resize_lock, flags);
+ if (info->resize_dpy) {
+ if (!xenfb_queue_full(info)) {
+ info->resize_dpy = 0;
+ xenfb_do_resize(info);
+ }
+ }
+ spin_unlock_irqrestore(&info->resize_lock, flags);
+}
+
+static void xenfb_refresh(struct xenfb_info *info,
+ int x1, int y1, int w, int h)
+{
+ unsigned long flags;
+ int x2 = x1 + w - 1;
+ int y2 = y1 + h - 1;
+
+ xenfb_handle_resize_dpy(info);
+
+ if (!info->update_wanted)
+ return;
+
+ spin_lock_irqsave(&info->dirty_lock, flags);
+
+ /* Combine with dirty rectangle: */
+ if (info->y1 < y1)
+ y1 = info->y1;
+ if (info->y2 > y2)
+ y2 = info->y2;
+ if (info->x1 < x1)
+ x1 = info->x1;
+ if (info->x2 > x2)
+ x2 = info->x2;
+
+ if (xenfb_queue_full(info)) {
+ /* Can't send right now, stash it in the dirty rectangle */
+ info->x1 = x1;
+ info->x2 = x2;
+ info->y1 = y1;
+ info->y2 = y2;
+ spin_unlock_irqrestore(&info->dirty_lock, flags);
+ return;
+ }
+
+ /* Clear dirty rectangle: */
+ info->x1 = info->y1 = INT_MAX;
+ info->x2 = info->y2 = 0;
+
+ spin_unlock_irqrestore(&info->dirty_lock, flags);
+
+ if (x1 <= x2 && y1 <= y2)
+ xenfb_do_update(info, x1, y1, x2 - x1 + 1, y2 - y1 + 1);
+}
+
+static void xenfb_deferred_io(struct fb_info *fb_info,
+ struct list_head *pagelist)
+{
+ struct xenfb_info *info = fb_info->par;
+ struct page *page;
+ unsigned long beg, end;
+ int y1, y2, miny, maxy;
+
+ miny = INT_MAX;
+ maxy = 0;
+ list_for_each_entry(page, pagelist, lru) {
+ beg = page->index << PAGE_SHIFT;
+ end = beg + PAGE_SIZE - 1;
+ y1 = beg / fb_info->fix.line_length;
+ y2 = end / fb_info->fix.line_length;
+ if (y2 >= fb_info->var.yres)
+ y2 = fb_info->var.yres - 1;
+ if (miny > y1)
+ miny = y1;
+ if (maxy < y2)
+ maxy = y2;
+ }
+ xenfb_refresh(info, 0, miny, fb_info->var.xres, maxy - miny + 1);
+}
+
+static struct fb_deferred_io xenfb_defio = {
+ .delay = HZ / 20,
+ .deferred_io = xenfb_deferred_io,
+};
+
+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;
+
+#define CNVT_TOHW(val, width) ((((val)<<(width))+0x7FFF-(val))>>16)
+ red = CNVT_TOHW(red, info->var.red.length);
+ green = CNVT_TOHW(green, info->var.green.length);
+ blue = CNVT_TOHW(blue, info->var.blue.length);
+ transp = CNVT_TOHW(transp, info->var.transp.length);
+#undef CNVT_TOHW
+
+ 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_fillrect(struct fb_info *p, const struct fb_fillrect *rect)
+{
+ struct xenfb_info *info = p->par;
+
+ sys_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;
+
+ sys_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;
+
+ sys_copyarea(p, area);
+ xenfb_refresh(info, area->dx, area->dy, area->width, area->height);
+}
+
+static ssize_t xenfb_write(struct fb_info *p, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct xenfb_info *info = p->par;
+ ssize_t res;
+
+ res = fb_sys_write(p, buf, count, ppos);
+ xenfb_refresh(info, 0, 0, info->page->width, info->page->height);
+ return res;
+}
+
+static int
+xenfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
+{
+ struct xenfb_info *xenfb_info;
+ int required_mem_len;
+
+ xenfb_info = info->par;
+
+ if (!xenfb_info->feature_resize) {
+ if (var->xres == video[KPARAM_WIDTH] &&
+ var->yres == video[KPARAM_HEIGHT] &&
+ var->bits_per_pixel == xenfb_info->page->depth) {
+ return 0;
+ }
+ return -EINVAL;
+ }
+
+ /* Can't resize past initial width and height */
+ if (var->xres > video[KPARAM_WIDTH] || var->yres > video[KPARAM_HEIGHT])
+ return -EINVAL;
+
+ required_mem_len = var->xres * var->yres * xenfb_info->page->depth / 8;
+ if (var->bits_per_pixel == xenfb_info->page->depth &&
+ var->xres <= info->fix.line_length / (XENFB_DEPTH / 8) &&
+ required_mem_len <= info->fix.smem_len) {
+ var->xres_virtual = var->xres;
+ var->yres_virtual = var->yres;
+ return 0;
+ }
+ return -EINVAL;
+}
+
+static int xenfb_set_par(struct fb_info *info)
+{
+ struct xenfb_info *xenfb_info;
+ unsigned long flags;
+
+ xenfb_info = info->par;
+
+ spin_lock_irqsave(&xenfb_info->resize_lock, flags);
+ xenfb_info->resize.type = XENFB_TYPE_RESIZE;
+ xenfb_info->resize.width = info->var.xres;
+ xenfb_info->resize.height = info->var.yres;
+ xenfb_info->resize.stride = info->fix.line_length;
+ xenfb_info->resize.depth = info->var.bits_per_pixel;
+ xenfb_info->resize.offset = 0;
+ xenfb_info->resize_dpy = 1;
+ spin_unlock_irqrestore(&xenfb_info->resize_lock, flags);
+ return 0;
+}
+
+static struct fb_ops xenfb_fb_ops = {
+ .owner = THIS_MODULE,
+ .fb_read = fb_sys_read,
+ .fb_write = xenfb_write,
+ .fb_setcolreg = xenfb_setcolreg,
+ .fb_fillrect = xenfb_fillrect,
+ .fb_copyarea = xenfb_copyarea,
+ .fb_imageblit = xenfb_imageblit,
+ .fb_check_var = xenfb_check_var,
+ .fb_set_par = xenfb_set_par,
+};
+
+static irqreturn_t xenfb_event_handler(int rq, void *dev_id)
+{
+ /*
+ * No in events recognized, simply ignore them all.
+ * If you need to recognize some, see xen-kbdfront's
+ * input_handler() for how to do that.
+ */
+ struct xenfb_info *info = dev_id;
+ struct xenfb_page *page = info->page;
+
+ if (page->in_cons != page->in_prod) {
+ info->page->in_cons = info->page->in_prod;
+ notify_remote_via_irq(info->irq);
+ }
+
+ /* Flush dirty rectangle: */
+ xenfb_refresh(info, INT_MAX, INT_MAX, -INT_MAX, -INT_MAX);
+
+ return IRQ_HANDLED;
+}
+
+static int xenfb_probe(struct xenbus_device *dev,
+ const struct xenbus_device_id *id)
+{
+ struct xenfb_info *info;
+ struct fb_info *fb_info;
+ int fb_size;
+ int val;
+ int ret = 0;
+
+ info = kzalloc(sizeof(*info), GFP_KERNEL);
+ if (info == NULL) {
+ xenbus_dev_fatal(dev, -ENOMEM, "allocating info structure");
+ return -ENOMEM;
+ }
+
+ /* Limit kernel param videoram amount to what is in xenstore */
+ if (xenbus_scanf(XBT_NIL, dev->otherend, "videoram", "%d", &val) == 1) {
+ if (val < video[KPARAM_MEM])
+ video[KPARAM_MEM] = val;
+ }
+
+ video[KPARAM_WIDTH] = xenbus_read_unsigned(dev->otherend, "width",
+ video[KPARAM_WIDTH]);
+ video[KPARAM_HEIGHT] = xenbus_read_unsigned(dev->otherend, "height",
+ video[KPARAM_HEIGHT]);
+
+ /* If requested res does not fit in available memory, use default */
+ fb_size = video[KPARAM_MEM] * 1024 * 1024;
+ if (video[KPARAM_WIDTH] * video[KPARAM_HEIGHT] * XENFB_DEPTH / 8
+ > fb_size) {
+ pr_warn("display parameters %d,%d,%d invalid, use defaults\n",
+ video[KPARAM_MEM], video[KPARAM_WIDTH],
+ video[KPARAM_HEIGHT]);
+ video[KPARAM_WIDTH] = XENFB_WIDTH;
+ video[KPARAM_HEIGHT] = XENFB_HEIGHT;
+ fb_size = XENFB_DEFAULT_FB_LEN;
+ }
+
+ dev_set_drvdata(&dev->dev, info);
+ info->xbdev = dev;
+ info->irq = -1;
+ info->x1 = info->y1 = INT_MAX;
+ spin_lock_init(&info->dirty_lock);
+ spin_lock_init(&info->resize_lock);
+
+ info->fb = vzalloc(fb_size);
+ if (info->fb == NULL)
+ goto error_nomem;
+
+ info->nr_pages = (fb_size + PAGE_SIZE - 1) >> PAGE_SHIFT;
+
+ info->gfns = vmalloc(array_size(sizeof(unsigned long), info->nr_pages));
+ if (!info->gfns)
+ goto error_nomem;
+
+ /* set up shared page */
+ info->page = (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
+ if (!info->page)
+ goto error_nomem;
+
+ /* abusing framebuffer_alloc() to allocate pseudo_palette */
+ fb_info = framebuffer_alloc(sizeof(u32) * 256, NULL);
+ if (fb_info == NULL)
+ goto error_nomem;
+
+ /* complete the abuse: */
+ fb_info->pseudo_palette = fb_info->par;
+ fb_info->par = info;
+
+ fb_info->screen_base = info->fb;
+
+ fb_info->fbops = &xenfb_fb_ops;
+ fb_info->var.xres_virtual = fb_info->var.xres = video[KPARAM_WIDTH];
+ fb_info->var.yres_virtual = fb_info->var.yres = video[KPARAM_HEIGHT];
+ fb_info->var.bits_per_pixel = XENFB_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 = fb_info->var.xres * XENFB_DEPTH / 8;
+ fb_info->fix.smem_start = 0;
+ fb_info->fix.smem_len = fb_size;
+ 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 | FBINFO_VIRTFB;
+
+ ret = fb_alloc_cmap(&fb_info->cmap, 256, 0);
+ if (ret < 0) {
+ framebuffer_release(fb_info);
+ xenbus_dev_fatal(dev, ret, "fb_alloc_cmap");
+ goto error;
+ }
+
+ fb_info->fbdefio = &xenfb_defio;
+ fb_deferred_io_init(fb_info);
+
+ xenfb_init_shared_page(info, fb_info);
+
+ ret = xenfb_connect_backend(dev, info);
+ if (ret < 0) {
+ xenbus_dev_fatal(dev, ret, "xenfb_connect_backend");
+ goto error_fb;
+ }
+
+ ret = register_framebuffer(fb_info);
+ if (ret) {
+ xenbus_dev_fatal(dev, ret, "register_framebuffer");
+ goto error_fb;
+ }
+ info->fb_info = fb_info;
+
+ xenfb_make_preferred_console();
+ return 0;
+
+error_fb:
+ fb_deferred_io_cleanup(fb_info);
+ fb_dealloc_cmap(&fb_info->cmap);
+ framebuffer_release(fb_info);
+error_nomem:
+ if (!ret) {
+ ret = -ENOMEM;
+ xenbus_dev_fatal(dev, ret, "allocating device memory");
+ }
+error:
+ xenfb_remove(dev);
+ return ret;
+}
+
+static void xenfb_make_preferred_console(void)
+{
+ struct console *c;
+
+ if (console_set_on_cmdline)
+ return;
+
+ console_lock();
+ for_each_console(c) {
+ if (!strcmp(c->name, "tty") && c->index == 0)
+ break;
+ }
+ console_unlock();
+ if (c) {
+ unregister_console(c);
+ c->flags |= CON_CONSDEV;
+ c->flags &= ~CON_PRINTBUFFER; /* don't print again */
+ register_console(c);
+ }
+}
+
+static int xenfb_resume(struct xenbus_device *dev)
+{
+ struct xenfb_info *info = dev_get_drvdata(&dev->dev);
+
+ xenfb_disconnect_backend(info);
+ xenfb_init_shared_page(info, info->fb_info);
+ return xenfb_connect_backend(dev, info);
+}
+
+static int xenfb_remove(struct xenbus_device *dev)
+{
+ struct xenfb_info *info = dev_get_drvdata(&dev->dev);
+
+ xenfb_disconnect_backend(info);
+ if (info->fb_info) {
+ fb_deferred_io_cleanup(info->fb_info);
+ unregister_framebuffer(info->fb_info);
+ fb_dealloc_cmap(&info->fb_info->cmap);
+ framebuffer_release(info->fb_info);
+ }
+ free_page((unsigned long)info->page);
+ vfree(info->gfns);
+ vfree(info->fb);
+ kfree(info);
+
+ return 0;
+}
+
+static unsigned long vmalloc_to_gfn(void *address)
+{
+ return xen_page_to_gfn(vmalloc_to_page(address));
+}
+
+static void xenfb_init_shared_page(struct xenfb_info *info,
+ struct fb_info *fb_info)
+{
+ int i;
+ int epd = PAGE_SIZE / sizeof(info->gfns[0]);
+
+ for (i = 0; i < info->nr_pages; i++)
+ info->gfns[i] = vmalloc_to_gfn(info->fb + i * PAGE_SIZE);
+
+ for (i = 0; i * epd < info->nr_pages; i++)
+ info->page->pd[i] = vmalloc_to_gfn(&info->gfns[i * epd]);
+
+ info->page->width = fb_info->var.xres;
+ info->page->height = fb_info->var.yres;
+ info->page->depth = fb_info->var.bits_per_pixel;
+ info->page->line_length = fb_info->fix.line_length;
+ info->page->mem_length = fb_info->fix.smem_len;
+ info->page->in_cons = info->page->in_prod = 0;
+ info->page->out_cons = info->page->out_prod = 0;
+}
+
+static int xenfb_connect_backend(struct xenbus_device *dev,
+ struct xenfb_info *info)
+{
+ int ret, evtchn, irq;
+ struct xenbus_transaction xbt;
+
+ ret = xenbus_alloc_evtchn(dev, &evtchn);
+ if (ret)
+ return ret;
+ irq = bind_evtchn_to_irqhandler(evtchn, xenfb_event_handler,
+ 0, dev->devicetype, info);
+ if (irq < 0) {
+ xenbus_free_evtchn(dev, evtchn);
+ xenbus_dev_fatal(dev, ret, "bind_evtchn_to_irqhandler");
+ return irq;
+ }
+ again:
+ ret = xenbus_transaction_start(&xbt);
+ if (ret) {
+ xenbus_dev_fatal(dev, ret, "starting transaction");
+ goto unbind_irq;
+ }
+ ret = xenbus_printf(xbt, dev->nodename, "page-ref", "%lu",
+ virt_to_gfn(info->page));
+ if (ret)
+ goto error_xenbus;
+ ret = xenbus_printf(xbt, dev->nodename, "event-channel", "%u",
+ evtchn);
+ if (ret)
+ goto error_xenbus;
+ ret = xenbus_printf(xbt, dev->nodename, "protocol", "%s",
+ XEN_IO_PROTO_ABI_NATIVE);
+ if (ret)
+ goto error_xenbus;
+ ret = xenbus_printf(xbt, dev->nodename, "feature-update", "1");
+ if (ret)
+ goto error_xenbus;
+ ret = xenbus_transaction_end(xbt, 0);
+ if (ret) {
+ if (ret == -EAGAIN)
+ goto again;
+ xenbus_dev_fatal(dev, ret, "completing transaction");
+ goto unbind_irq;
+ }
+
+ xenbus_switch_state(dev, XenbusStateInitialised);
+ info->irq = irq;
+ return 0;
+
+ error_xenbus:
+ xenbus_transaction_end(xbt, 1);
+ xenbus_dev_fatal(dev, ret, "writing xenstore");
+ unbind_irq:
+ unbind_from_irqhandler(irq, info);
+ return ret;
+}
+
+static void xenfb_disconnect_backend(struct xenfb_info *info)
+{
+ /* Prevent xenfb refresh */
+ info->update_wanted = 0;
+ if (info->irq >= 0)
+ unbind_from_irqhandler(info->irq, info);
+ info->irq = -1;
+}
+
+static void xenfb_backend_changed(struct xenbus_device *dev,
+ enum xenbus_state backend_state)
+{
+ struct xenfb_info *info = dev_get_drvdata(&dev->dev);
+
+ switch (backend_state) {
+ case XenbusStateInitialising:
+ case XenbusStateInitialised:
+ case XenbusStateReconfiguring:
+ case XenbusStateReconfigured:
+ case XenbusStateUnknown:
+ break;
+
+ case XenbusStateInitWait:
+ xenbus_switch_state(dev, XenbusStateConnected);
+ break;
+
+ case XenbusStateConnected:
+ /*
+ * Work around xenbus race condition: If backend goes
+ * through InitWait to Connected fast enough, we can
+ * get Connected twice here.
+ */
+ if (dev->state != XenbusStateConnected)
+ /* no InitWait seen yet, fudge it */
+ xenbus_switch_state(dev, XenbusStateConnected);
+
+ if (xenbus_read_unsigned(info->xbdev->otherend,
+ "request-update", 0))
+ info->update_wanted = 1;
+
+ info->feature_resize = xenbus_read_unsigned(dev->otherend,
+ "feature-resize", 0);
+ break;
+
+ case XenbusStateClosed:
+ if (dev->state == XenbusStateClosed)
+ break;
+ /* Missed the backend's CLOSING state -- fallthrough */
+ case XenbusStateClosing:
+ xenbus_frontend_closed(dev);
+ break;
+ }
+}
+
+static const struct xenbus_device_id xenfb_ids[] = {
+ { "vfb" },
+ { "" }
+};
+
+static struct xenbus_driver xenfb_driver = {
+ .ids = xenfb_ids,
+ .probe = xenfb_probe,
+ .remove = xenfb_remove,
+ .resume = xenfb_resume,
+ .otherend_changed = xenfb_backend_changed,
+};
+
+static int __init xenfb_init(void)
+{
+ if (!xen_domain())
+ return -ENODEV;
+
+ /* Nothing to do if running in dom0. */
+ if (xen_initial_domain())
+ return -ENODEV;
+
+ if (!xen_has_pv_devices())
+ return -ENODEV;
+
+ return xenbus_register_frontend(&xenfb_driver);
+}
+
+static void __exit xenfb_cleanup(void)
+{
+ xenbus_unregister_driver(&xenfb_driver);
+}
+
+module_init(xenfb_init);
+module_exit(xenfb_cleanup);
+
+MODULE_DESCRIPTION("Xen virtual framebuffer device frontend");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("xen:vfb");