* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
-#include <linux/config.h>
#include <linux/console.h>
#include <linux/cpumask.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/delay.h>
+
#include <asm/uaccess.h>
-#include <asm/hvconsole.h>
+
+#include "hvc_console.h"
#define HVC_MAJOR 229
#define HVC_MINOR 0
#define HVC_CLOSE_WAIT (HZ/100) /* 1/10 of a second */
/*
- * The Linux TTY code does not support dynamic addition of tty derived devices
- * so we need to know how many tty devices we might need when space is allocated
- * for the tty device. Since this driver supports hotplug of vty adapters we
- * need to make sure we have enough allocated.
+ * These sizes are most efficient for vio, because they are the
+ * native transfer size. We could make them selectable in the
+ * future to better deal with backends that want other buffer sizes.
*/
-#define HVC_ALLOC_TTY_ADAPTERS 8
-
#define N_OUTBUF 16
#define N_INBUF 16
-#define __ALIGNED__ __attribute__((__aligned__(8)))
+#define __ALIGNED__ __attribute__((__aligned__(sizeof(long))))
static struct tty_driver *hvc_driver;
static struct task_struct *hvc_task;
struct tty_struct *tty;
unsigned int count;
int do_wakeup;
- char outbuf[N_OUTBUF] __ALIGNED__;
+ char *outbuf;
+ int outbuf_size;
int n_outbuf;
uint32_t vtermno;
struct hv_ops *ops;
void hvc_console_print(struct console *co, const char *b, unsigned count)
{
- char c[16] __ALIGNED__;
+ char c[N_OUTBUF] __ALIGNED__;
unsigned i = 0, n = 0;
int r, donecr = 0, index = co->index;
struct kobject *kobjp;
/* Auto increments kobject reference if found. */
- if (!(hp = hvc_get_by_index(tty->index))) {
- printk(KERN_WARNING "hvc_console: tty open failed, no vty associated with tty.\n");
+ if (!(hp = hvc_get_by_index(tty->index)))
return -ENODEV;
- }
spin_lock_irqsave(&hp->lock, flags);
/* Check and then increment for fast path open. */
spin_unlock_irqrestore(&hp->lock, flags);
/* check error, fallback to non-irq */
if (irq != NO_IRQ)
- rc = request_irq(irq, hvc_handle_interrupt, SA_INTERRUPT, "hvc_console", hp);
+ rc = request_irq(irq, hvc_handle_interrupt, IRQF_DISABLED, "hvc_console", hp);
/*
* If the request_irq() fails and we return an error. The tty layer
n = hp->ops->put_chars(hp->vtermno, hp->outbuf, hp->n_outbuf);
if (n <= 0) {
- if (n == 0)
+ if (n == 0) {
+ hp->do_wakeup = 1;
return;
+ }
/* throw away output on error; this happens when
there is no session connected to the vterm. */
hp->n_outbuf = 0;
hp->do_wakeup = 1;
}
-static inline int __hvc_write_kernel(struct hvc_struct *hp,
- const unsigned char *buf, int count)
+static int hvc_write(struct tty_struct *tty, const unsigned char *buf, int count)
{
+ struct hvc_struct *hp = tty->driver_data;
unsigned long flags;
int rsize, written = 0;
+ /* This write was probably executed during a tty close. */
+ if (!hp)
+ return -EPIPE;
+
+ if (hp->count <= 0)
+ return -EIO;
+
spin_lock_irqsave(&hp->lock, flags);
/* Push pending writes */
if (hp->n_outbuf > 0)
hvc_push(hp);
- while (count > 0 && (rsize = N_OUTBUF - hp->n_outbuf) > 0) {
+ while (count > 0 && (rsize = hp->outbuf_size - hp->n_outbuf) > 0) {
if (rsize > count)
rsize = count;
memcpy(hp->outbuf + hp->n_outbuf, buf, rsize);
}
spin_unlock_irqrestore(&hp->lock, flags);
- return written;
-}
-static int hvc_write(struct tty_struct *tty, const unsigned char *buf, int count)
-{
- struct hvc_struct *hp = tty->driver_data;
- int written;
-
- /* This write was probably executed during a tty close. */
- if (!hp)
- return -EPIPE;
-
- if (hp->count <= 0)
- return -EIO;
-
- written = __hvc_write_kernel(hp, buf, count);
-
/*
* Racy, but harmless, kick thread if there is still pending data.
- * There really is nothing wrong with kicking the thread, even if there
- * is no buffered data.
*/
if (hp->n_outbuf)
hvc_kick();
if (!hp)
return -1;
- return N_OUTBUF - hp->n_outbuf;
+ return hp->outbuf_size - hp->n_outbuf;
}
static int hvc_chars_in_buffer(struct tty_struct *tty)
#define HVC_POLL_READ 0x00000001
#define HVC_POLL_WRITE 0x00000002
-#define HVC_POLL_QUICK 0x00000004
static int hvc_poll(struct hvc_struct *hp)
{
/* Push pending writes */
if (hp->n_outbuf > 0)
hvc_push(hp);
+
/* Reschedule us if still some write pending */
if (hp->n_outbuf > 0)
poll_mask |= HVC_POLL_WRITE;
spin_unlock_irqrestore(&hp->lock, flags);
tty_hangup(tty);
spin_lock_irqsave(&hp->lock, flags);
+ } else if ( n == -EAGAIN ) {
+ /*
+ * Some back-ends can only ensure a certain min
+ * num of bytes read, which may be > 'count'.
+ * Let the tty clear the flip buff to make room.
+ */
+ poll_mask |= HVC_POLL_READ;
}
break;
}
tty_insert_flip_char(tty, buf[i], 0);
}
- /*
- * Account for the total amount read in one loop, and if above
- * 64 bytes, we do a quick schedule loop to let the tty grok
- * the data and eventually throttle us.
- */
read_total += n;
- if (read_total >= 64) {
- poll_mask |= HVC_POLL_QUICK;
- break;
- }
}
throttled:
/* Wakeup write queue if necessary */
do {
poll_mask = 0;
hvc_kicked = 0;
+ try_to_freeze();
wmb();
if (cpus_empty(cpus_in_xmon)) {
spin_lock(&hvc_structs_lock);
poll_mask |= HVC_POLL_READ;
if (hvc_kicked)
continue;
- if (poll_mask & HVC_POLL_QUICK) {
+ if (poll_mask & HVC_POLL_WRITE) {
yield();
continue;
}
};
struct hvc_struct __devinit *hvc_alloc(uint32_t vtermno, int irq,
- struct hv_ops *ops)
+ struct hv_ops *ops, int outbuf_size)
{
struct hvc_struct *hp;
int i;
- hp = kmalloc(sizeof(*hp), GFP_KERNEL);
+ hp = kmalloc(ALIGN(sizeof(*hp), sizeof(long)) + outbuf_size,
+ GFP_KERNEL);
if (!hp)
return ERR_PTR(-ENOMEM);
hp->vtermno = vtermno;
hp->irq = irq;
hp->ops = ops;
+ hp->outbuf_size = outbuf_size;
+ hp->outbuf = &((char *)hp)[ALIGN(sizeof(*hp), sizeof(long))];
kobject_init(&hp->kobj);
hp->kobj.ktype = &hvc_kobj_type;
* see if this vterm id matches one registered for console.
*/
for (i=0; i < MAX_NR_HVC_CONSOLES; i++)
- if (vtermnos[i] == hp->vtermno)
+ if (vtermnos[i] == hp->vtermno &&
+ cons_ops[i] == hp->ops)
break;
/* no matching slot, just use a counter */
* interfaces start to become available. */
int __init hvc_init(void)
{
+ struct tty_driver *drv;
+
/* We need more than hvc_count adapters due to hotplug additions. */
- hvc_driver = alloc_tty_driver(HVC_ALLOC_TTY_ADAPTERS);
- if (!hvc_driver)
+ drv = alloc_tty_driver(HVC_ALLOC_TTY_ADAPTERS);
+ if (!drv)
return -ENOMEM;
- hvc_driver->owner = THIS_MODULE;
- hvc_driver->devfs_name = "hvc/";
- hvc_driver->driver_name = "hvc";
- hvc_driver->name = "hvc";
- hvc_driver->major = HVC_MAJOR;
- hvc_driver->minor_start = HVC_MINOR;
- hvc_driver->type = TTY_DRIVER_TYPE_SYSTEM;
- hvc_driver->init_termios = tty_std_termios;
- hvc_driver->flags = TTY_DRIVER_REAL_RAW;
- tty_set_operations(hvc_driver, &hvc_ops);
+ drv->owner = THIS_MODULE;
+ drv->driver_name = "hvc";
+ drv->name = "hvc";
+ drv->major = HVC_MAJOR;
+ drv->minor_start = HVC_MINOR;
+ drv->type = TTY_DRIVER_TYPE_SYSTEM;
+ drv->init_termios = tty_std_termios;
+ drv->flags = TTY_DRIVER_REAL_RAW;
+ tty_set_operations(drv, &hvc_ops);
/* Always start the kthread because there can be hotplug vty adapters
* 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(hvc_driver);
+ put_tty_driver(drv);
return -EIO;
}
- if (tty_register_driver(hvc_driver))
+ if (tty_register_driver(drv))
panic("Couldn't register hvc console driver\n");
+ mb();
+ hvc_driver = drv;
return 0;
}
module_init(hvc_init);
git.openpandora.org / pandora-kernel.git / blobdiff