Revert "powerpc/mm: Fix bug in pagetable cache cleanup with CONFIG_PPC_SUBPAGE_PROT"

This reverts commit c045256d146800ea1d741a8e9e377dada6b7e195.

It breaks build when CONFIG_PPC_SUBPAGE_PROT is not set. I will
commit a fixed version separately

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

3 files changed, 7 insertions, 16 deletions

diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index 50f867d..6810128 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -835,9 +835,9 @@ void demote_segment_4k(struct mm_struct *mm, unsigned long addr)
  * Result is 0: full permissions, _PAGE_RW: read-only,
  * _PAGE_USER or _PAGE_USER|_PAGE_RW: no access.
  */
-static int subpage_protection(struct mm_struct *mm, unsigned long ea)
+static int subpage_protection(pgd_t *pgdir, unsigned long ea)
 {
-	struct subpage_prot_table *spt = &mm->context.spt;
+	struct subpage_prot_table *spt = pgd_subpage_prot(pgdir);
 	u32 spp = 0;
 	u32 **sbpm, *sbpp;
 
@@ -865,7 +865,7 @@ static int subpage_protection(struct mm_struct *mm, unsigned long ea)
 }
 
 #else /* CONFIG_PPC_SUBPAGE_PROT */
-static inline int subpage_protection(struct mm_struct *mm, unsigned long ea)
+static inline int subpage_protection(pgd_t *pgdir, unsigned long ea)
 {
 	return 0;
 }
diff --git a/arch/powerpc/mm/mmu_context_hash64.c b/arch/powerpc/mm/mmu_context_hash64.c
index b910d37..b9e4cc2 100644
--- a/arch/powerpc/mm/mmu_context_hash64.c
+++ b/arch/powerpc/mm/mmu_context_hash64.c
@@ -76,7 +76,6 @@ int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
 	 */
 	if (slice_mm_new_context(mm))
 		slice_set_user_psize(mm, mmu_virtual_psize);
-	subpage_prot_init_new_context(mm);
 	mm->context.id = index;
 
 	return 0;
@@ -93,6 +92,5 @@ EXPORT_SYMBOL_GPL(__destroy_context);
 void destroy_context(struct mm_struct *mm)
 {
 	__destroy_context(mm->context.id);
-	subpage_prot_free(mm);
 	mm->context.id = NO_CONTEXT;
 }
diff --git a/arch/powerpc/mm/subpage-prot.c b/arch/powerpc/mm/subpage-prot.c
index a040b81..4cafc0c 100644
--- a/arch/powerpc/mm/subpage-prot.c
+++ b/arch/powerpc/mm/subpage-prot.c
@@ -24,9 +24,9 @@
  * Also makes sure that the subpage_prot_table structure is
  * reinitialized for the next user.
  */
-void subpage_prot_free(struct mm_struct *mm)
+void subpage_prot_free(pgd_t *pgd)
 {
-	struct subpage_prot_table *spt = &mm->context.spt;
+	struct subpage_prot_table *spt = pgd_subpage_prot(pgd);
 	unsigned long i, j, addr;
 	u32 **p;
 
@@ -51,13 +51,6 @@ void subpage_prot_free(struct mm_struct *mm)
 	spt->maxaddr = 0;
 }
 
-void subpage_prot_init_new_context(struct mm_struct *mm)
-{
-	struct subpage_prot_table *spt = &mm->context.spt;
-
-	memset(spt, 0, sizeof(*spt));
-}
-
 static void hpte_flush_range(struct mm_struct *mm, unsigned long addr,
 			     int npages)
 {
@@ -94,7 +87,7 @@ static void hpte_flush_range(struct mm_struct *mm, unsigned long addr,
 static void subpage_prot_clear(unsigned long addr, unsigned long len)
 {
 	struct mm_struct *mm = current->mm;
-	struct subpage_prot_table *spt = &mm->context.spt;
+	struct subpage_prot_table *spt = pgd_subpage_prot(mm->pgd);
 	u32 **spm, *spp;
 	int i, nw;
 	unsigned long next, limit;
@@ -143,7 +136,7 @@ static void subpage_prot_clear(unsigned long addr, unsigned long len)
 long sys_subpage_prot(unsigned long addr, unsigned long len, u32 __user *map)
 {
 	struct mm_struct *mm = current->mm;
-	struct subpage_prot_table *spt = &mm->context.spt;
+	struct subpage_prot_table *spt = pgd_subpage_prot(mm->pgd);
 	u32 **spm, *spp;
 	int i, nw;
 	unsigned long next, limit;