[PATCH 4.9 64/93] powerpc/iommu: Pass mm_struct to init/cleanup helpers

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Alexey Kardashevskiy <aik@xxxxxxxxx>

[ Upstream commit 88f54a3581eb9deaa3bd1aade40aef266d782385 ]

We are going to get rid of @current references in mmu_context_boos3s64.c
and cache mm_struct in the VFIO container. Since mm_context_t does not
have reference counting, we will be using mm_struct which does have
the reference counter.

This changes mm_iommu_init/mm_iommu_cleanup to receive mm_struct rather
than mm_context_t (which is embedded into mm).

This should not cause any behavioral change.

Signed-off-by: Alexey Kardashevskiy <aik@xxxxxxxxx>
Reviewed-by: David Gibson <david@xxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 arch/powerpc/include/asm/mmu_context.h |    4 ++--
 arch/powerpc/kernel/setup-common.c     |    2 +-
 arch/powerpc/mm/mmu_context_book3s64.c |    4 ++--
 arch/powerpc/mm/mmu_context_iommu.c    |    9 +++++----
 4 files changed, 10 insertions(+), 9 deletions(-)

--- a/arch/powerpc/include/asm/mmu_context.h
+++ b/arch/powerpc/include/asm/mmu_context.h
@@ -23,8 +23,8 @@ extern bool mm_iommu_preregistered(void)
 extern long mm_iommu_get(unsigned long ua, unsigned long entries,
 		struct mm_iommu_table_group_mem_t **pmem);
 extern long mm_iommu_put(struct mm_iommu_table_group_mem_t *mem);
-extern void mm_iommu_init(mm_context_t *ctx);
-extern void mm_iommu_cleanup(mm_context_t *ctx);
+extern void mm_iommu_init(struct mm_struct *mm);
+extern void mm_iommu_cleanup(struct mm_struct *mm);
 extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup(unsigned long ua,
 		unsigned long size);
 extern struct mm_iommu_table_group_mem_t *mm_iommu_find(unsigned long ua,
--- a/arch/powerpc/kernel/setup-common.c
+++ b/arch/powerpc/kernel/setup-common.c
@@ -915,7 +915,7 @@ void __init setup_arch(char **cmdline_p)
 	init_mm.context.pte_frag = NULL;
 #endif
 #ifdef CONFIG_SPAPR_TCE_IOMMU
-	mm_iommu_init(&init_mm.context);
+	mm_iommu_init(&init_mm);
 #endif
 	irqstack_early_init();
 	exc_lvl_early_init();
--- a/arch/powerpc/mm/mmu_context_book3s64.c
+++ b/arch/powerpc/mm/mmu_context_book3s64.c
@@ -115,7 +115,7 @@ int init_new_context(struct task_struct
 	mm->context.pte_frag = NULL;
 #endif
 #ifdef CONFIG_SPAPR_TCE_IOMMU
-	mm_iommu_init(&mm->context);
+	mm_iommu_init(mm);
 #endif
 	return 0;
 }
@@ -160,7 +160,7 @@ static inline void destroy_pagetable_pag
 void destroy_context(struct mm_struct *mm)
 {
 #ifdef CONFIG_SPAPR_TCE_IOMMU
-	mm_iommu_cleanup(&mm->context);
+	mm_iommu_cleanup(mm);
 #endif
 
 #ifdef CONFIG_PPC_ICSWX
--- a/arch/powerpc/mm/mmu_context_iommu.c
+++ b/arch/powerpc/mm/mmu_context_iommu.c
@@ -373,16 +373,17 @@ void mm_iommu_mapped_dec(struct mm_iommu
 }
 EXPORT_SYMBOL_GPL(mm_iommu_mapped_dec);
 
-void mm_iommu_init(mm_context_t *ctx)
+void mm_iommu_init(struct mm_struct *mm)
 {
-	INIT_LIST_HEAD_RCU(&ctx->iommu_group_mem_list);
+	INIT_LIST_HEAD_RCU(&mm->context.iommu_group_mem_list);
 }
 
-void mm_iommu_cleanup(mm_context_t *ctx)
+void mm_iommu_cleanup(struct mm_struct *mm)
 {
 	struct mm_iommu_table_group_mem_t *mem, *tmp;
 
-	list_for_each_entry_safe(mem, tmp, &ctx->iommu_group_mem_list, next) {
+	list_for_each_entry_safe(mem, tmp, &mm->context.iommu_group_mem_list,
+			next) {
 		list_del_rcu(&mem->next);
 		mm_iommu_do_free(mem);
 	}