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Diffstat (limited to 'drivers/lguest/lguest_bus.c')
-rw-r--r--drivers/lguest/lguest_bus.c220
1 files changed, 0 insertions, 220 deletions
diff --git a/drivers/lguest/lguest_bus.c b/drivers/lguest/lguest_bus.c
deleted file mode 100644
index 2e9a202be44..00000000000
--- a/drivers/lguest/lguest_bus.c
+++ /dev/null
@@ -1,220 +0,0 @@
-/*P:050 Lguest guests use a very simple bus for devices. It's a simple array
- * of device descriptors contained just above the top of normal memory. The
- * lguest bus is 80% tedious boilerplate code. :*/
-#include <linux/init.h>
-#include <linux/bootmem.h>
-#include <linux/lguest_bus.h>
-#include <asm/io.h>
-#include <asm/paravirt.h>
-
-struct lguest_device_desc *lguest_devices;
-
-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
-};
-
-/*D:130 The generic bus infrastructure requires a function which says whether a
- * device matches a driver. For us, it is simple: "struct lguest_driver"
- * contains a "device_type" field which indicates what type of device it can
- * handle, so we just cast the args and compare: */
-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",
- }
-};
-
-/*D:140 This is the callback which occurs once the bus infrastructure matches
- * up a device and driver, ie. in response to add_lguest_device() calling
- * device_register(), or register_lguest_driver() calling driver_register().
- *
- * At the moment it's always the latter: the devices are added first, since
- * scan_devices() is called from a "core_initcall", and the drivers themselves
- * called later as a normal "initcall". But it would work the other way too.
- *
- * So now we have the happy couple, we add the status bit to indicate that we
- * found a driver. If the driver truly loves the device, it will return
- * happiness from its probe function (ok, perhaps this wasn't my greatest
- * analogy), and we set the final "driver ok" bit so the Host sees it's all
- * green. */
-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;
-}
-
-/* The last part of the bus infrastructure is the function lguest drivers use
- * to register themselves. Firstly, we do nothing if there's no lguest bus
- * (ie. this is not a Guest), otherwise we fill in the embedded generic "struct
- * driver" fields and call the generic driver_register(). */
-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);
-}
-
-/* At the moment we build all the drivers into the kernel because they're so
- * simple: 8144 bytes for all three of them as I type this. And as the console
- * really needs to be built in, it's actually only 3527 bytes for the network
- * and block drivers.
- *
- * If they get complex it will make sense for them to be modularized, so we
- * need to explicitly export the symbol.
- *
- * I don't think non-GPL modules make sense, so it's a GPL-only export.
- */
-EXPORT_SYMBOL_GPL(register_lguest_driver);
-
-/*D:120 This is the core of the lguest bus: actually adding a new device.
- * It's a separate function because it's neater that way, and because an
- * earlier version of the code supported hotplug and unplug. They were removed
- * early on because they were never used.
- *
- * As Andrew Tridgell says, "Untested code is buggy code".
- *
- * It's worth reading this carefully: we start with an index into the array of
- * "struct lguest_device_desc"s indicating the device which is new: */
-static void add_lguest_device(unsigned int index)
-{
- struct lguest_device *new;
-
- /* Each "struct lguest_device_desc" has a "status" field, which the
- * Guest updates as the device is probed. In the worst case, the Host
- * can look at these bits to tell what part of device setup failed,
- * even if the console isn't available. */
- 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;
- }
-
- /* The "struct lguest_device" setup is pretty straight-forward example
- * code. */
- 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);
-
- /* device_register() causes the bus infrastructure to look for a
- * matching driver. */
- 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);
- }
-}
-
-/*D:110 scan_devices() simply iterates through the device array. The type 0
- * is reserved to mean "no device", and anything else means we have found a
- * device: add it. */
-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);
-}
-
-/*D:100 Fairly early in boot, lguest_bus_init() is called to set up the lguest
- * bus. We check that we are a Guest by checking paravirt_ops.name: there are
- * other ways of checking, but this seems most obvious to me.
- *
- * So we can access the array of "struct lguest_device_desc"s easily, we map
- * that memory and store the pointer in the global "lguest_devices". Then we
- * register the bus with the core. Doing two registrations seems clunky to me,
- * but it seems to be the correct sysfs incantation.
- *
- * Finally we call scan_devices() which adds all the devices found in the
- * "struct lguest_device_desc" array. */
-static int __init lguest_bus_init(void)
-{
- if (strcmp(pv_info.name, "lguest") != 0)
- return 0;
-
- /* Devices are in a single 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;
-}
-/* Do this after core stuff, before devices. */
-postcore_initcall(lguest_bus_init);