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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/powerpc/mm/mmu_context_hash64.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/powerpc/mm/mmu_context_hash64.c')
-rw-r--r--kernel/arch/powerpc/mm/mmu_context_hash64.c146
1 files changed, 146 insertions, 0 deletions
diff --git a/kernel/arch/powerpc/mm/mmu_context_hash64.c b/kernel/arch/powerpc/mm/mmu_context_hash64.c
new file mode 100644
index 000000000..178876aef
--- /dev/null
+++ b/kernel/arch/powerpc/mm/mmu_context_hash64.c
@@ -0,0 +1,146 @@
+/*
+ * 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 <linux/export.h>
+#include <linux/gfp.h>
+#include <linux/slab.h>
+
+#include <asm/mmu_context.h>
+#include <asm/pgalloc.h>
+
+#include "icswx.h"
+
+static DEFINE_SPINLOCK(mmu_context_lock);
+static DEFINE_IDA(mmu_context_ida);
+
+int __init_new_context(void)
+{
+ int index;
+ int err;
+
+again:
+ if (!ida_pre_get(&mmu_context_ida, GFP_KERNEL))
+ return -ENOMEM;
+
+ spin_lock(&mmu_context_lock);
+ err = ida_get_new_above(&mmu_context_ida, 1, &index);
+ spin_unlock(&mmu_context_lock);
+
+ if (err == -EAGAIN)
+ goto again;
+ else if (err)
+ return err;
+
+ if (index > MAX_USER_CONTEXT) {
+ spin_lock(&mmu_context_lock);
+ ida_remove(&mmu_context_ida, index);
+ spin_unlock(&mmu_context_lock);
+ return -ENOMEM;
+ }
+
+ return index;
+}
+EXPORT_SYMBOL_GPL(__init_new_context);
+
+int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
+{
+ int index;
+
+ index = __init_new_context();
+ if (index < 0)
+ return index;
+
+ /* The old code would re-promote on fork, we don't do that
+ * when using slices as it could cause problem promoting slices
+ * that have been forced down to 4K
+ */
+ if (slice_mm_new_context(mm))
+ slice_set_user_psize(mm, mmu_virtual_psize);
+ subpage_prot_init_new_context(mm);
+ mm->context.id = index;
+#ifdef CONFIG_PPC_ICSWX
+ mm->context.cop_lockp = kmalloc(sizeof(spinlock_t), GFP_KERNEL);
+ if (!mm->context.cop_lockp) {
+ __destroy_context(index);
+ subpage_prot_free(mm);
+ mm->context.id = MMU_NO_CONTEXT;
+ return -ENOMEM;
+ }
+ spin_lock_init(mm->context.cop_lockp);
+#endif /* CONFIG_PPC_ICSWX */
+
+#ifdef CONFIG_PPC_64K_PAGES
+ mm->context.pte_frag = NULL;
+#endif
+ return 0;
+}
+
+void __destroy_context(int context_id)
+{
+ spin_lock(&mmu_context_lock);
+ ida_remove(&mmu_context_ida, context_id);
+ spin_unlock(&mmu_context_lock);
+}
+EXPORT_SYMBOL_GPL(__destroy_context);
+
+#ifdef CONFIG_PPC_64K_PAGES
+static void destroy_pagetable_page(struct mm_struct *mm)
+{
+ int count;
+ void *pte_frag;
+ struct page *page;
+
+ pte_frag = mm->context.pte_frag;
+ if (!pte_frag)
+ return;
+
+ page = virt_to_page(pte_frag);
+ /* drop all the pending references */
+ count = ((unsigned long)pte_frag & ~PAGE_MASK) >> PTE_FRAG_SIZE_SHIFT;
+ /* We allow PTE_FRAG_NR fragments from a PTE page */
+ count = atomic_sub_return(PTE_FRAG_NR - count, &page->_count);
+ if (!count) {
+ pgtable_page_dtor(page);
+ free_hot_cold_page(page, 0);
+ }
+}
+
+#else
+static inline void destroy_pagetable_page(struct mm_struct *mm)
+{
+ return;
+}
+#endif
+
+
+void destroy_context(struct mm_struct *mm)
+{
+
+#ifdef CONFIG_PPC_ICSWX
+ drop_cop(mm->context.acop, mm);
+ kfree(mm->context.cop_lockp);
+ mm->context.cop_lockp = NULL;
+#endif /* CONFIG_PPC_ICSWX */
+
+ destroy_pagetable_page(mm);
+ __destroy_context(mm->context.id);
+ subpage_prot_free(mm);
+ mm->context.id = MMU_NO_CONTEXT;
+}