mirror of
https://github.com/torvalds/linux.git
synced 2024-12-11 13:41:55 +00:00
aab944606f
With the changes in the random tree, IRQF_SAMPLE_RANDOM is now a
no-op; interrupt randomness is now collected unconditionally in a very
low-overhead fashion; see commit 775f4b297b. The IRQF_SAMPLE_RANDOM
flag was scheduled to be removed in 2009 on the
feature-removal-schedule, so this patch is preparation for the final
removal of this flag.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
50 lines
1004 B
C
50 lines
1004 B
C
/*
|
|
* Copyright (C) 2002 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
|
|
* Licensed under the GPL
|
|
*/
|
|
|
|
#include <linux/interrupt.h>
|
|
#include "irq_kern.h"
|
|
#include "os.h"
|
|
#include "sigio.h"
|
|
|
|
/* Protected by sigio_lock() called from write_sigio_workaround */
|
|
static int sigio_irq_fd = -1;
|
|
|
|
static irqreturn_t sigio_interrupt(int irq, void *data)
|
|
{
|
|
char c;
|
|
|
|
os_read_file(sigio_irq_fd, &c, sizeof(c));
|
|
reactivate_fd(sigio_irq_fd, SIGIO_WRITE_IRQ);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
int write_sigio_irq(int fd)
|
|
{
|
|
int err;
|
|
|
|
err = um_request_irq(SIGIO_WRITE_IRQ, fd, IRQ_READ, sigio_interrupt,
|
|
0, "write sigio", NULL);
|
|
if (err) {
|
|
printk(KERN_ERR "write_sigio_irq : um_request_irq failed, "
|
|
"err = %d\n", err);
|
|
return -1;
|
|
}
|
|
sigio_irq_fd = fd;
|
|
return 0;
|
|
}
|
|
|
|
/* These are called from os-Linux/sigio.c to protect its pollfds arrays. */
|
|
static DEFINE_SPINLOCK(sigio_spinlock);
|
|
|
|
void sigio_lock(void)
|
|
{
|
|
spin_lock(&sigio_spinlock);
|
|
}
|
|
|
|
void sigio_unlock(void)
|
|
{
|
|
spin_unlock(&sigio_spinlock);
|
|
}
|