This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / arch / powerpc / mm / mmu_context_64.c

diff --git a/arch/powerpc/mm/mmu_context_64.c b/arch/powerpc/mm/mmu_context_64.c
new file mode 100644 (file)
index 0000000..714a84d
--- /dev/null
+++ b/arch/powerpc/mm/mmu_context_64.c
@@ -0,0 +1,63 @@
+/*
+ *  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/config.h>
+#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) {
+               idr_remove(&mmu_context_idr, index);
+               return -ENOMEM;
+       }
+
+       mm->context.id = index;
+
+       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;
+}