#include <linux/init.h>
#include <linux/kbd_kern.h>
#include <linux/kernel.h>
-#include <linux/kobject.h>
+#include <linux/kref.h>
#include <linux/kthread.h>
#include <linux/list.h>
#include <linux/module.h>
/* Picks up late kicks after list walk but before schedule() */
static int hvc_kicked;
+static int hvc_init(void);
+
#ifdef CONFIG_MAGIC_SYSRQ
static int sysrq_pressed;
#endif
int irq_requested;
int irq;
struct list_head next;
- struct kobject kobj; /* ref count & hvc_struct lifetime */
+ struct kref kref; /* ref count & hvc_struct lifetime */
};
/* dynamic list of hvc_struct instances */
-static struct list_head hvc_structs = LIST_HEAD_INIT(hvc_structs);
+static LIST_HEAD(hvc_structs);
/*
* Protect the list of hvc_struct instances from inserts and removals during
/*
* Do not call this function with either the hvc_structs_lock or the hvc_struct
- * lock held. If successful, this function increments the kobject reference
+ * lock held. If successful, this function increments the kref reference
* count against the target hvc_struct so it should be released when finished.
*/
static struct hvc_struct *hvc_get_by_index(int index)
list_for_each_entry(hp, &hvc_structs, next) {
spin_lock_irqsave(&hp->lock, flags);
if (hp->index == index) {
- kobject_get(&hp->kobj);
+ kref_get(&hp->kref);
spin_unlock_irqrestore(&hp->lock, flags);
spin_unlock(&hvc_structs_lock);
return hp;
}
console_initcall(hvc_console_init);
+/* callback when the kboject ref count reaches zero. */
+static void destroy_hvc_struct(struct kref *kref)
+{
+ struct hvc_struct *hp = container_of(kref, struct hvc_struct, kref);
+ unsigned long flags;
+
+ spin_lock(&hvc_structs_lock);
+
+ spin_lock_irqsave(&hp->lock, flags);
+ list_del(&(hp->next));
+ spin_unlock_irqrestore(&hp->lock, flags);
+
+ spin_unlock(&hvc_structs_lock);
+
+ kfree(hp);
+}
+
/*
* hvc_instantiate() is an early console discovery method which locates
* consoles * prior to the vio subsystem discovering them. Hotplugged
/* make sure no no tty has been registered in this index */
hp = hvc_get_by_index(index);
if (hp) {
- kobject_put(&hp->kobj);
+ kref_put(&hp->kref, destroy_hvc_struct);
return -1;
}
unsigned long flags;
int irq = 0;
int rc = 0;
- struct kobject *kobjp;
- /* Auto increments kobject reference if found. */
+ /* Auto increments kref reference if found. */
if (!(hp = hvc_get_by_index(tty->index)))
return -ENODEV;
if (irq)
hp->irq_requested = 1;
- kobjp = &hp->kobj;
-
spin_unlock_irqrestore(&hp->lock, flags);
/* check error, fallback to non-irq */
if (irq)
* If the request_irq() fails and we return an error. The tty layer
* will call hvc_close() after a failed open but we don't want to clean
* up there so we'll clean up here and clear out the previously set
- * tty fields and return the kobject reference.
+ * tty fields and return the kref reference.
*/
if (rc) {
spin_lock_irqsave(&hp->lock, flags);
hp->irq_requested = 0;
spin_unlock_irqrestore(&hp->lock, flags);
tty->driver_data = NULL;
- kobject_put(kobjp);
+ kref_put(&hp->kref, destroy_hvc_struct);
printk(KERN_ERR "hvc_open: request_irq failed with rc %d.\n", rc);
}
/* Force wakeup of the polling thread */
static void hvc_close(struct tty_struct *tty, struct file * filp)
{
struct hvc_struct *hp;
- struct kobject *kobjp;
int irq = 0;
unsigned long flags;
/*
* No driver_data means that this close was issued after a failed
* hvc_open by the tty layer's release_dev() function and we can just
- * exit cleanly because the kobject reference wasn't made.
+ * exit cleanly because the kref reference wasn't made.
*/
if (!tty->driver_data)
return;
hp = tty->driver_data;
spin_lock_irqsave(&hp->lock, flags);
- kobjp = &hp->kobj;
if (--hp->count == 0) {
if (hp->irq_requested)
irq = hp->irq;
spin_unlock_irqrestore(&hp->lock, flags);
}
- kobject_put(kobjp);
+ kref_put(&hp->kref, destroy_hvc_struct);
}
static void hvc_hangup(struct tty_struct *tty)
unsigned long flags;
int irq = 0;
int temp_open_count;
- struct kobject *kobjp;
if (!hp)
return;
return;
}
- kobjp = &hp->kobj;
temp_open_count = hp->count;
hp->count = 0;
hp->n_outbuf = 0;
free_irq(irq, hp);
while(temp_open_count) {
--temp_open_count;
- kobject_put(kobjp);
+ kref_put(&hp->kref, destroy_hvc_struct);
}
}
* calling hvc_poll() who determines whether a console adapter support
* interrupts.
*/
-int khvcd(void *unused)
+static int khvcd(void *unused)
{
int poll_mask;
struct hvc_struct *hp;
+ set_freezable();
__set_current_state(TASK_RUNNING);
do {
poll_mask = 0;
.chars_in_buffer = hvc_chars_in_buffer,
};
-/* callback when the kboject ref count reaches zero. */
-static void destroy_hvc_struct(struct kobject *kobj)
-{
- struct hvc_struct *hp = container_of(kobj, struct hvc_struct, kobj);
- unsigned long flags;
-
- spin_lock(&hvc_structs_lock);
-
- spin_lock_irqsave(&hp->lock, flags);
- list_del(&(hp->next));
- spin_unlock_irqrestore(&hp->lock, flags);
-
- spin_unlock(&hvc_structs_lock);
-
- kfree(hp);
-}
-
-static struct kobj_type hvc_kobj_type = {
- .release = destroy_hvc_struct,
-};
-
struct hvc_struct __devinit *hvc_alloc(uint32_t vtermno, int irq,
struct hv_ops *ops, int outbuf_size)
{
struct hvc_struct *hp;
int i;
+ /* We wait until a driver actually comes along */
+ if (!hvc_driver) {
+ int err = hvc_init();
+ if (err)
+ return ERR_PTR(err);
+ }
+
hp = kmalloc(ALIGN(sizeof(*hp), sizeof(long)) + outbuf_size,
GFP_KERNEL);
if (!hp)
hp->outbuf_size = outbuf_size;
hp->outbuf = &((char *)hp)[ALIGN(sizeof(*hp), sizeof(long))];
- kobject_init(&hp->kobj);
- hp->kobj.ktype = &hvc_kobj_type;
+ kref_init(&hp->kref);
spin_lock_init(&hp->lock);
spin_lock(&hvc_structs_lock);
int __devexit hvc_remove(struct hvc_struct *hp)
{
unsigned long flags;
- struct kobject *kobjp;
struct tty_struct *tty;
spin_lock_irqsave(&hp->lock, flags);
tty = hp->tty;
- kobjp = &hp->kobj;
if (hp->index < MAX_NR_HVC_CONSOLES)
vtermnos[hp->index] = -1;
spin_unlock_irqrestore(&hp->lock, flags);
/*
- * We 'put' the instance that was grabbed when the kobject instance
- * was initialized using kobject_init(). Let the last holder of this
- * kobject cause it to be removed, which will probably be the tty_hangup
+ * We 'put' the instance that was grabbed when the kref instance
+ * was initialized using kref_init(). Let the last holder of this
+ * kref cause it to be removed, which will probably be the tty_hangup
* below.
*/
- kobject_put(kobjp);
+ kref_put(&hp->kref, destroy_hvc_struct);
/*
* This function call will auto chain call hvc_hangup. The tty should
return 0;
}
-/* Driver initialization. Follow console initialization. This is where the TTY
- * interfaces start to become available. */
-static int __init hvc_init(void)
+/* Driver initialization: called as soon as someone uses hvc_alloc(). */
+static int hvc_init(void)
{
struct tty_driver *drv;
+ int err;
/* We need more than hvc_count adapters due to hotplug additions. */
drv = alloc_tty_driver(HVC_ALLOC_TTY_ADAPTERS);
- if (!drv)
- return -ENOMEM;
+ if (!drv) {
+ err = -ENOMEM;
+ goto out;
+ }
drv->owner = THIS_MODULE;
drv->driver_name = "hvc";
* added later. */
hvc_task = kthread_run(khvcd, NULL, "khvcd");
if (IS_ERR(hvc_task)) {
- panic("Couldn't create kthread for console.\n");
- put_tty_driver(drv);
- return -EIO;
+ printk(KERN_ERR "Couldn't create kthread for console.\n");
+ err = PTR_ERR(hvc_task);
+ goto put_tty;
}
- if (tty_register_driver(drv))
- panic("Couldn't register hvc console driver\n");
+ err = tty_register_driver(drv);
+ if (err) {
+ printk(KERN_ERR "Couldn't register hvc console driver\n");
+ goto stop_thread;
+ }
+ /* FIXME: This mb() seems completely random. Remove it. */
mb();
hvc_driver = drv;
return 0;
+
+put_tty:
+ put_tty_driver(hvc_driver);
+stop_thread:
+ kthread_stop(hvc_task);
+ hvc_task = NULL;
+out:
+ return err;
}
-module_init(hvc_init);
/* This isn't particularly necessary due to this being a console driver
* but it is nice to be thorough.
*/
static void __exit hvc_exit(void)
{
- kthread_stop(hvc_task);
+ if (hvc_driver) {
+ kthread_stop(hvc_task);
- tty_unregister_driver(hvc_driver);
- /* return tty_struct instances allocated in hvc_init(). */
- put_tty_driver(hvc_driver);
- unregister_console(&hvc_con_driver);
+ tty_unregister_driver(hvc_driver);
+ /* return tty_struct instances allocated in hvc_init(). */
+ put_tty_driver(hvc_driver);
+ unregister_console(&hvc_con_driver);
+ }
}
module_exit(hvc_exit);
projects / linux-2.6-omap-h63xx.git / blobdiff