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Diffstat (limited to 'arch/powerpc/mm/mmu_context_book3s64.c')
-rw-r--r--arch/powerpc/mm/mmu_context_book3s64.c116
1 files changed, 86 insertions, 30 deletions
diff --git a/arch/powerpc/mm/mmu_context_book3s64.c b/arch/powerpc/mm/mmu_context_book3s64.c
index 73bf6e14c3aa..c6dca2ae78ef 100644
--- a/arch/powerpc/mm/mmu_context_book3s64.c
+++ b/arch/powerpc/mm/mmu_context_book3s64.c
@@ -30,17 +30,16 @@
static DEFINE_SPINLOCK(mmu_context_lock);
static DEFINE_IDA(mmu_context_ida);
-int __init_new_context(void)
+static int alloc_context_id(int min_id, int max_id)
{
- int index;
- int err;
+ int index, 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);
+ err = ida_get_new_above(&mmu_context_ida, min_id, &index);
spin_unlock(&mmu_context_lock);
if (err == -EAGAIN)
@@ -48,7 +47,7 @@ again:
else if (err)
return err;
- if (index > MAX_USER_CONTEXT) {
+ if (index > max_id) {
spin_lock(&mmu_context_lock);
ida_remove(&mmu_context_ida, index);
spin_unlock(&mmu_context_lock);
@@ -57,48 +56,105 @@ again:
return index;
}
-EXPORT_SYMBOL_GPL(__init_new_context);
-static int radix__init_new_context(struct mm_struct *mm, int index)
+
+void hash__reserve_context_id(int id)
+{
+ int rc, result = 0;
+
+ do {
+ if (!ida_pre_get(&mmu_context_ida, GFP_KERNEL))
+ break;
+
+ spin_lock(&mmu_context_lock);
+ rc = ida_get_new_above(&mmu_context_ida, id, &result);
+ spin_unlock(&mmu_context_lock);
+ } while (rc == -EAGAIN);
+
+ WARN(result != id, "mmu: Failed to reserve context id %d (rc %d)\n", id, result);
+}
+
+int hash__alloc_context_id(void)
+{
+ unsigned long max;
+
+ if (mmu_has_feature(MMU_FTR_68_BIT_VA))
+ max = MAX_USER_CONTEXT;
+ else
+ max = MAX_USER_CONTEXT_65BIT_VA;
+
+ return alloc_context_id(MIN_USER_CONTEXT, max);
+}
+EXPORT_SYMBOL_GPL(hash__alloc_context_id);
+
+static int hash__init_new_context(struct mm_struct *mm)
+{
+ int index;
+
+ index = hash__alloc_context_id();
+ if (index < 0)
+ return index;
+
+ /*
+ * We do switch_slb() early in fork, even before we setup the
+ * mm->context.addr_limit. Default to max task size so that we copy the
+ * default values to paca which will help us to handle slb miss early.
+ */
+ mm->context.addr_limit = TASK_SIZE_128TB;
+
+ /*
+ * 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.
+ *
+ * For book3s we have MMU_NO_CONTEXT set to be ~0. Hence check
+ * explicitly against context.id == 0. This ensures that we properly
+ * initialize context slice details for newly allocated mm's (which will
+ * have id == 0) and don't alter context slice inherited via fork (which
+ * will have id != 0).
+ *
+ * We should not be calling init_new_context() on init_mm. Hence a
+ * check against 0 is OK.
+ */
+ if (mm->context.id == 0)
+ slice_set_user_psize(mm, mmu_virtual_psize);
+
+ subpage_prot_init_new_context(mm);
+
+ return index;
+}
+
+static int radix__init_new_context(struct mm_struct *mm)
{
unsigned long rts_field;
+ int index;
+
+ index = alloc_context_id(1, PRTB_ENTRIES - 1);
+ if (index < 0)
+ return index;
/*
* set the process table entry,
*/
rts_field = radix__get_tree_size();
process_tb[index].prtb0 = cpu_to_be64(rts_field | __pa(mm->pgd) | RADIX_PGD_INDEX_SIZE);
- return 0;
+
+ mm->context.npu_context = NULL;
+
+ return index;
}
int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
{
int index;
- index = __init_new_context();
+ if (radix_enabled())
+ index = radix__init_new_context(mm);
+ else
+ index = hash__init_new_context(mm);
+
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
- *
- * For book3s we have MMU_NO_CONTEXT set to be ~0. Hence check
- * explicitly against context.id == 0. This ensures that we
- * properly initialize context slice details for newly allocated
- * mm's (which will have id == 0) and don't alter context slice
- * inherited via fork (which will have id != 0).
- *
- * We should not be calling init_new_context() on init_mm. Hence a
- * check against 0 is ok.
- */
- if (mm->context.id == 0)
- 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);