forked from Minki/linux
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
/*
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* Copyright (C) 2002 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
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* Licensed under the GPL
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*/
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#include <linux/interrupt.h>
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#include "irq_kern.h"
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#include "os.h"
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#include "sigio.h"
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/* Protected by sigio_lock() called from write_sigio_workaround */
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static int sigio_irq_fd = -1;
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static irqreturn_t sigio_interrupt(int irq, void *data)
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{
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char c;
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os_read_file(sigio_irq_fd, &c, sizeof(c));
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reactivate_fd(sigio_irq_fd, SIGIO_WRITE_IRQ);
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return IRQ_HANDLED;
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}
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int write_sigio_irq(int fd)
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{
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int err;
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err = um_request_irq(SIGIO_WRITE_IRQ, fd, IRQ_READ, sigio_interrupt,
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0, "write sigio", NULL);
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if (err) {
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printk(KERN_ERR "write_sigio_irq : um_request_irq failed, "
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"err = %d\n", err);
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return -1;
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}
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sigio_irq_fd = fd;
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return 0;
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}
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/* These are called from os-Linux/sigio.c to protect its pollfds arrays. */
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static DEFINE_SPINLOCK(sigio_spinlock);
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void sigio_lock(void)
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{
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spin_lock(&sigio_spinlock);
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}
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void sigio_unlock(void)
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{
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spin_unlock(&sigio_spinlock);
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}
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