6ab3d5624e
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
68 lines
1.5 KiB
C
68 lines
1.5 KiB
C
/*
|
|
* MMU context allocation for 64-bit kernels.
|
|
*
|
|
* Copyright (C) 2004 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/string.h>
|
|
#include <linux/types.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/idr.h>
|
|
|
|
#include <asm/mmu_context.h>
|
|
|
|
static DEFINE_SPINLOCK(mmu_context_lock);
|
|
static DEFINE_IDR(mmu_context_idr);
|
|
|
|
int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
|
|
{
|
|
int index;
|
|
int err;
|
|
|
|
again:
|
|
if (!idr_pre_get(&mmu_context_idr, GFP_KERNEL))
|
|
return -ENOMEM;
|
|
|
|
spin_lock(&mmu_context_lock);
|
|
err = idr_get_new_above(&mmu_context_idr, NULL, 1, &index);
|
|
spin_unlock(&mmu_context_lock);
|
|
|
|
if (err == -EAGAIN)
|
|
goto again;
|
|
else if (err)
|
|
return err;
|
|
|
|
if (index > MAX_CONTEXT) {
|
|
spin_lock(&mmu_context_lock);
|
|
idr_remove(&mmu_context_idr, index);
|
|
spin_unlock(&mmu_context_lock);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
mm->context.id = index;
|
|
mm->context.user_psize = mmu_virtual_psize;
|
|
mm->context.sllp = SLB_VSID_USER |
|
|
mmu_psize_defs[mmu_virtual_psize].sllp;
|
|
|
|
return 0;
|
|
}
|
|
|
|
void destroy_context(struct mm_struct *mm)
|
|
{
|
|
spin_lock(&mmu_context_lock);
|
|
idr_remove(&mmu_context_idr, mm->context.id);
|
|
spin_unlock(&mmu_context_lock);
|
|
|
|
mm->context.id = NO_CONTEXT;
|
|
}
|