mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-23 11:04:44 +08:00
9d67028090
Some processors, like embedded, that already have a PID register that is managed by the system. This patch separates the ACOP and PID processing into separate files so that the ACOP code can be shared. Signed-off-by: Jimi Xenidis <jimix@pobox.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
88 lines
1.8 KiB
C
88 lines
1.8 KiB
C
/*
|
|
* ICSWX and ACOP/PID Management
|
|
*
|
|
* Copyright (C) 2011 Anton Blanchard, IBM Corp. <anton@samba.org>
|
|
*
|
|
* 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.
|
|
*
|
|
*/
|
|
|
|
#include <linux/sched.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/types.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/idr.h>
|
|
#include <linux/module.h>
|
|
#include "icswx.h"
|
|
|
|
#define COP_PID_MIN (COP_PID_NONE + 1)
|
|
#define COP_PID_MAX (0xFFFF)
|
|
|
|
static DEFINE_SPINLOCK(mmu_context_acop_lock);
|
|
static DEFINE_IDA(cop_ida);
|
|
|
|
static int new_cop_pid(struct ida *ida, int min_id, int max_id,
|
|
spinlock_t *lock)
|
|
{
|
|
int index;
|
|
int err;
|
|
|
|
again:
|
|
if (!ida_pre_get(ida, GFP_KERNEL))
|
|
return -ENOMEM;
|
|
|
|
spin_lock(lock);
|
|
err = ida_get_new_above(ida, min_id, &index);
|
|
spin_unlock(lock);
|
|
|
|
if (err == -EAGAIN)
|
|
goto again;
|
|
else if (err)
|
|
return err;
|
|
|
|
if (index > max_id) {
|
|
spin_lock(lock);
|
|
ida_remove(ida, index);
|
|
spin_unlock(lock);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
return index;
|
|
}
|
|
|
|
int get_cop_pid(struct mm_struct *mm)
|
|
{
|
|
int pid;
|
|
|
|
if (mm->context.cop_pid == COP_PID_NONE) {
|
|
pid = new_cop_pid(&cop_ida, COP_PID_MIN, COP_PID_MAX,
|
|
&mmu_context_acop_lock);
|
|
if (pid >= 0)
|
|
mm->context.cop_pid = pid;
|
|
}
|
|
return mm->context.cop_pid;
|
|
}
|
|
|
|
int disable_cop_pid(struct mm_struct *mm)
|
|
{
|
|
int free_pid = COP_PID_NONE;
|
|
|
|
if ((!mm->context.acop) && (mm->context.cop_pid != COP_PID_NONE)) {
|
|
free_pid = mm->context.cop_pid;
|
|
mm->context.cop_pid = COP_PID_NONE;
|
|
}
|
|
return free_pid;
|
|
}
|
|
|
|
void free_cop_pid(int free_pid)
|
|
{
|
|
spin_lock(&mmu_context_acop_lock);
|
|
ida_remove(&cop_ida, free_pid);
|
|
spin_unlock(&mmu_context_acop_lock);
|
|
}
|