linux/drivers/char/hvc_console.h
Hendrik Brueckner 254be490f2 hvc_console: Provide (un)locked version for hvc_resize()
Rename the locking free hvc_resize() function to __hvc_resize() and
provide an inline function that locks the hvc_struct and calls
__hvc_resize().

The rationale for this patch is that virtio_console calls the hvc_resize()
function without locking the hvc_struct. So it needs to call the lock
itself.

According to naming rules, the unlocked version is renamed and
prefixed with "__".
References to unlocked function calls in hvc back-ends has been updated.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-09-24 15:12:47 +10:00

119 lines
3.6 KiB
C

/*
* hvc_console.h
* Copyright (C) 2005 IBM Corporation
*
* Author(s):
* Ryan S. Arnold <rsa@us.ibm.com>
*
* hvc_console header information:
* moved here from arch/powerpc/include/asm/hvconsole.h
* and drivers/char/hvc_console.c
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef HVC_CONSOLE_H
#define HVC_CONSOLE_H
#include <linux/kref.h>
#include <linux/tty.h>
#include <linux/spinlock.h>
/*
* This is the max number of console adapters that can/will be found as
* console devices on first stage console init. Any number beyond this range
* can't be used as a console device but is still a valid tty device.
*/
#define MAX_NR_HVC_CONSOLES 16
/*
* 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.
*/
#define HVC_ALLOC_TTY_ADAPTERS 8
struct hvc_struct {
spinlock_t lock;
int index;
struct tty_struct *tty;
int count;
int do_wakeup;
char *outbuf;
int outbuf_size;
int n_outbuf;
uint32_t vtermno;
struct hv_ops *ops;
int irq_requested;
int data;
struct winsize ws;
struct work_struct tty_resize;
struct list_head next;
struct kref kref; /* ref count & hvc_struct lifetime */
};
/* implemented by a low level driver */
struct hv_ops {
int (*get_chars)(uint32_t vtermno, char *buf, int count);
int (*put_chars)(uint32_t vtermno, const char *buf, int count);
/* Callbacks for notification. Called in open, close and hangup */
int (*notifier_add)(struct hvc_struct *hp, int irq);
void (*notifier_del)(struct hvc_struct *hp, int irq);
void (*notifier_hangup)(struct hvc_struct *hp, int irq);
};
/* Register a vterm and a slot index for use as a console (console_init) */
extern int hvc_instantiate(uint32_t vtermno, int index, struct hv_ops *ops);
/* register a vterm for hvc tty operation (module_init or hotplug add) */
extern struct hvc_struct * __devinit hvc_alloc(uint32_t vtermno, int data,
struct hv_ops *ops, int outbuf_size);
/* remove a vterm from hvc tty operation (module_exit or hotplug remove) */
extern int hvc_remove(struct hvc_struct *hp);
/* data available */
int hvc_poll(struct hvc_struct *hp);
void hvc_kick(void);
/* Resize hvc tty terminal window */
extern void __hvc_resize(struct hvc_struct *hp, struct winsize ws);
static inline void hvc_resize(struct hvc_struct *hp, struct winsize ws)
{
unsigned long flags;
spin_lock_irqsave(&hp->lock, flags);
__hvc_resize(hp, ws);
spin_unlock_irqrestore(&hp->lock, flags);
}
/* default notifier for irq based notification */
extern int notifier_add_irq(struct hvc_struct *hp, int data);
extern void notifier_del_irq(struct hvc_struct *hp, int data);
extern void notifier_hangup_irq(struct hvc_struct *hp, int data);
#if defined(CONFIG_XMON) && defined(CONFIG_SMP)
#include <asm/xmon.h>
#else
static inline int cpus_are_in_xmon(void)
{
return 0;
}
#endif
#endif // HVC_CONSOLE_H