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authorAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>2016-04-29 23:26:03 +1000
committerMichael Ellerman <mpe@ellerman.id.au>2016-05-01 18:33:07 +1000
commitf5df4b4be9ae5abf748065d7f40d6027bf9af148 (patch)
tree8a86633a0328cc192e1ef41cd24ddb5c78873192 /arch/powerpc/mm/mmu_context_book3s64.c
parent7e381c0ff618cab3e687e953b72f59ef2a891ba9 (diff)
powerpc/mm: Rename mmu_context_hash64.c to mmu_context_book3s64.c
This file now contains both hash and radix specific code. Rename it to indicate this better. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/mm/mmu_context_book3s64.c')
-rw-r--r--arch/powerpc/mm/mmu_context_book3s64.c178
1 files changed, 178 insertions, 0 deletions
diff --git a/arch/powerpc/mm/mmu_context_book3s64.c b/arch/powerpc/mm/mmu_context_book3s64.c
new file mode 100644
index 000000000000..b5288b460bef
--- /dev/null
+++ b/arch/powerpc/mm/mmu_context_book3s64.c
@@ -0,0 +1,178 @@
+/*
+ * 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);
+static int radix__init_new_context(struct mm_struct *mm, int index)
+{
+ unsigned long rts_field;
+
+ /*
+ * set the process table entry,
+ */
+ rts_field = 3ull << PPC_BITLSHIFT(2);
+ process_tb[index].prtb0 = cpu_to_be64(rts_field | __pa(mm->pgd) | RADIX_PGD_INDEX_SIZE);
+ return 0;
+}
+
+int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
+{
+ int index;
+
+ index = __init_new_context();
+ if (index < 0)
+ return index;
+
+ if (radix_enabled()) {
+ radix__init_new_context(mm, index);
+ } else {
+
+ /* 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
+#ifdef CONFIG_SPAPR_TCE_IOMMU
+ mm_iommu_init(&mm->context);
+#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 */
+ if (page_ref_sub_and_test(page, PTE_FRAG_NR - 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_SPAPR_TCE_IOMMU
+ mm_iommu_cleanup(&mm->context);
+#endif
+
+#ifdef CONFIG_PPC_ICSWX
+ drop_cop(mm->context.acop, mm);
+ kfree(mm->context.cop_lockp);
+ mm->context.cop_lockp = NULL;
+#endif /* CONFIG_PPC_ICSWX */
+
+ if (radix_enabled())
+ process_tb[mm->context.id].prtb1 = 0;
+ else
+ subpage_prot_free(mm);
+ destroy_pagetable_page(mm);
+ __destroy_context(mm->context.id);
+ mm->context.id = MMU_NO_CONTEXT;
+}
+
+#ifdef CONFIG_PPC_RADIX_MMU
+void radix__switch_mmu_context(struct mm_struct *prev, struct mm_struct *next)
+{
+ mtspr(SPRN_PID, next->context.id);
+ asm volatile("isync": : :"memory");
+}
+#endif