1 files changed, 148 insertions, 0 deletions

diff --git a/drivers/lguest/lguest_bus.c b/drivers/lguest/lguest_bus.c
new file mode 100644
index 000000000000..18d6ab21a43b
--- /dev/null
+++ b/drivers/lguest/lguest_bus.c
@@ -0,0 +1,148 @@
+#include <linux/init.h>
+#include <linux/bootmem.h>
+#include <linux/lguest_bus.h>
+#include <asm/io.h>
+
+static ssize_t type_show(struct device *_dev,
+                         struct device_attribute *attr, char *buf)
+{
+        struct lguest_device *dev = container_of(_dev,struct lguest_device,dev);
+        return sprintf(buf, "%hu", lguest_devices[dev->index].type);
+}
+static ssize_t features_show(struct device *_dev,
+                             struct device_attribute *attr, char *buf)
+{
+        struct lguest_device *dev = container_of(_dev,struct lguest_device,dev);
+        return sprintf(buf, "%hx", lguest_devices[dev->index].features);
+}
+static ssize_t pfn_show(struct device *_dev,
+                         struct device_attribute *attr, char *buf)
+{
+        struct lguest_device *dev = container_of(_dev,struct lguest_device,dev);
+        return sprintf(buf, "%u", lguest_devices[dev->index].pfn);
+}
+static ssize_t status_show(struct device *_dev,
+                           struct device_attribute *attr, char *buf)
+{
+        struct lguest_device *dev = container_of(_dev,struct lguest_device,dev);
+        return sprintf(buf, "%hx", lguest_devices[dev->index].status);
+}
+static ssize_t status_store(struct device *_dev, struct device_attribute *attr,
+                            const char *buf, size_t count)
+{
+        struct lguest_device *dev = container_of(_dev,struct lguest_device,dev);
+        if (sscanf(buf, "%hi", &lguest_devices[dev->index].status) != 1)
+                return -EINVAL;
+        return count;
+}
+static struct device_attribute lguest_dev_attrs[] = {
+        __ATTR_RO(type),
+        __ATTR_RO(features),
+        __ATTR_RO(pfn),
+        __ATTR(status, 0644, status_show, status_store),
+        __ATTR_NULL
+};
+
+static int lguest_dev_match(struct device *_dev, struct device_driver *_drv)
+{
+        struct lguest_device *dev = container_of(_dev,struct lguest_device,dev);
+        struct lguest_driver *drv = container_of(_drv,struct lguest_driver,drv);
+
+        return (drv->device_type == lguest_devices[dev->index].type);
+}
+
+struct lguest_bus {
+        struct bus_type bus;
+        struct device dev;
+};
+
+static struct lguest_bus lguest_bus = {
+        .bus = {
+                .name  = "lguest",
+                .match = lguest_dev_match,
+                .dev_attrs = lguest_dev_attrs,
+        },
+        .dev = {
+                .parent = NULL,
+                .bus_id = "lguest",
+        }
+};
+
+static int lguest_dev_probe(struct device *_dev)
+{
+        int ret;
+        struct lguest_device *dev = container_of(_dev,struct lguest_device,dev);
+        struct lguest_driver *drv = container_of(dev->dev.driver,
+                                                struct lguest_driver, drv);
+
+        lguest_devices[dev->index].status |= LGUEST_DEVICE_S_DRIVER;
+        ret = drv->probe(dev);
+        if (ret == 0)
+                lguest_devices[dev->index].status |= LGUEST_DEVICE_S_DRIVER_OK;
+        return ret;
+}
+
+int register_lguest_driver(struct lguest_driver *drv)
+{
+        if (!lguest_devices)
+                return 0;
+
+        drv->drv.bus = &lguest_bus.bus;
+        drv->drv.name = drv->name;
+        drv->drv.owner = drv->owner;
+        drv->drv.probe = lguest_dev_probe;
+
+        return driver_register(&drv->drv);
+}
+EXPORT_SYMBOL_GPL(register_lguest_driver);
+
+static void add_lguest_device(unsigned int index)
+{
+        struct lguest_device *new;
+
+        lguest_devices[index].status |= LGUEST_DEVICE_S_ACKNOWLEDGE;
+        new = kmalloc(sizeof(struct lguest_device), GFP_KERNEL);
+        if (!new) {
+                printk(KERN_EMERG "Cannot allocate lguest device %u\n", index);
+                lguest_devices[index].status |= LGUEST_DEVICE_S_FAILED;
+                return;
+        }
+
+        new->index = index;
+        new->private = NULL;
+        memset(&new->dev, 0, sizeof(new->dev));
+        new->dev.parent = &lguest_bus.dev;
+        new->dev.bus = &lguest_bus.bus;
+        sprintf(new->dev.bus_id, "%u", index);
+        if (device_register(&new->dev) != 0) {
+                printk(KERN_EMERG "Cannot register lguest device %u\n", index);
+                lguest_devices[index].status |= LGUEST_DEVICE_S_FAILED;
+                kfree(new);
+        }
+}
+
+static void scan_devices(void)
+{
+        unsigned int i;
+
+        for (i = 0; i < LGUEST_MAX_DEVICES; i++)
+                if (lguest_devices[i].type)
+                        add_lguest_device(i);
+}
+
+static int __init lguest_bus_init(void)
+{
+        if (strcmp(paravirt_ops.name, "lguest") != 0)
+                return 0;
+
+        /* Devices are in page above top of "normal" mem. */
+        lguest_devices = lguest_map(max_pfn<<PAGE_SHIFT, 1);
+
+        if (bus_register(&lguest_bus.bus) != 0
+            || device_register(&lguest_bus.dev) != 0)
+                panic("lguest bus registration failed");
+
+        scan_devices();
+        return 0;
+}
+postcore_initcall(lguest_bus_init);