powerpc/mm: Add helpers for accessing hash translation related variables

We want to switch to allocating them runtime only when hash translation is
enabled. Add helpers so that both book3s and nohash can be adapted to
upcoming change easily.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/include/asm/book3s/64/mmu-hash.h

@@ -657,8 +657,8 @@ extern void slb_set_size(u16 size);
 
 /* 4 bits per slice and we have one slice per 1TB */
 #define SLICE_ARRAY_SIZE	(H_PGTABLE_RANGE >> 41)
-#define TASK_SLICE_ARRAY_SZ(x)	((x)->context.slb_addr_limit >> 41)
-
+#define LOW_SLICE_ARRAY_SZ	(BITS_PER_LONG / BITS_PER_BYTE)
+#define TASK_SLICE_ARRAY_SZ(x)	((x)->slb_addr_limit >> 41)
 #ifndef __ASSEMBLY__
 
 #ifdef CONFIG_PPC_SUBPAGE_PROT

arch/powerpc/include/asm/book3s/64/mmu.h

@@ -139,7 +139,7 @@ typedef struct {
 	struct npu_context *npu_context;
 
 	 /* SLB page size encodings*/
-	unsigned char low_slices_psize[BITS_PER_LONG / BITS_PER_BYTE];
+	unsigned char low_slices_psize[LOW_SLICE_ARRAY_SZ];
 	unsigned char high_slices_psize[SLICE_ARRAY_SIZE];
 	unsigned long slb_addr_limit;
 # ifdef CONFIG_PPC_64K_PAGES
@@ -174,6 +174,67 @@ typedef struct {
 #endif
 } mm_context_t;
 
+static inline u16 mm_ctx_user_psize(mm_context_t *ctx)
+{
+	return ctx->user_psize;
+}
+
+static inline void mm_ctx_set_user_psize(mm_context_t *ctx, u16 user_psize)
+{
+	ctx->user_psize = user_psize;
+}
+
+static inline unsigned char *mm_ctx_low_slices(mm_context_t *ctx)
+{
+	return ctx->low_slices_psize;
+}
+
+static inline unsigned char *mm_ctx_high_slices(mm_context_t *ctx)
+{
+	return ctx->high_slices_psize;
+}
+
+static inline unsigned long mm_ctx_slb_addr_limit(mm_context_t *ctx)
+{
+	return ctx->slb_addr_limit;
+}
+
+static inline void mm_ctx_set_slb_addr_limit(mm_context_t *ctx, unsigned long limit)
+{
+	ctx->slb_addr_limit = limit;
+}
+
+#ifdef CONFIG_PPC_64K_PAGES
+static inline struct slice_mask *mm_ctx_slice_mask_64k(mm_context_t *ctx)
+{
+	return &ctx->mask_64k;
+}
+#endif
+
+static inline struct slice_mask *mm_ctx_slice_mask_4k(mm_context_t *ctx)
+{
+	return &ctx->mask_4k;
+}
+
+#ifdef CONFIG_HUGETLB_PAGE
+static inline struct slice_mask *mm_ctx_slice_mask_16m(mm_context_t *ctx)
+{
+	return &ctx->mask_16m;
+}
+
+static inline struct slice_mask *mm_ctx_slice_mask_16g(mm_context_t *ctx)
+{
+	return &ctx->mask_16g;
+}
+#endif
+
+#ifdef CONFIG_PPC_SUBPAGE_PROT
+static inline struct subpage_prot_table *mm_ctx_subpage_prot(mm_context_t *ctx)
+{
+	return &ctx->spt;
+}
+#endif
+
 /*
  * The current system page and segment sizes
  */

arch/powerpc/include/asm/nohash/32/mmu-8xx.h

@@ -181,6 +181,7 @@
 #ifdef CONFIG_PPC_MM_SLICES
 #include <asm/nohash/32/slice.h>
 #define SLICE_ARRAY_SIZE	(1 << (32 - SLICE_LOW_SHIFT - 1))
+#define LOW_SLICE_ARRAY_SZ	SLICE_ARRAY_SIZE
 #endif
 
 #ifndef __ASSEMBLY__
@@ -207,6 +208,55 @@ typedef struct {
 	void *pte_frag;
 } mm_context_t;
 
+#ifdef CONFIG_PPC_MM_SLICES
+static inline u16 mm_ctx_user_psize(mm_context_t *ctx)
+{
+	return ctx->user_psize;
+}
+
+static inline void mm_ctx_set_user_psize(mm_context_t *ctx, u16 user_psize)
+{
+	ctx->user_psize = user_psize;
+}
+
+static inline unsigned char *mm_ctx_low_slices(mm_context_t *ctx)
+{
+	return ctx->low_slices_psize;
+}
+
+static inline unsigned char *mm_ctx_high_slices(mm_context_t *ctx)
+{
+	return ctx->high_slices_psize;
+}
+
+static inline unsigned long mm_ctx_slb_addr_limit(mm_context_t *ctx)
+{
+	return ctx->slb_addr_limit;
+}
+
+static inline void mm_ctx_set_slb_addr_limit(mm_context_t *ctx, unsigned long limit)
+{
+	ctx->slb_addr_limit = limit;
+}
+
+static inline struct slice_mask *mm_ctx_slice_mask_base(mm_context_t *ctx)
+{
+	return &ctx->mask_base_psize;
+}
+
+#ifdef CONFIG_HUGETLB_PAGE
+static inline struct slice_mask *mm_ctx_slice_mask_512k(mm_context_t *ctx)
+{
+	return &ctx->mask_512k;
+}
+
+static inline struct slice_mask *mm_ctx_slice_mask_8m(mm_context_t *ctx)
+{
+	return &ctx->mask_8m;
+}
+#endif
+#endif /* CONFIG_PPC_MM_SLICE */
+
 #define PHYS_IMMR_BASE (mfspr(SPRN_IMMR) & 0xfff80000)
 #define VIRT_IMMR_BASE (__fix_to_virt(FIX_IMMR_BASE))
 

arch/powerpc/kernel/paca.c

@@ -267,12 +267,12 @@ void copy_mm_to_paca(struct mm_struct *mm)
 
 	get_paca()->mm_ctx_id = context->id;
 #ifdef CONFIG_PPC_MM_SLICES
-	VM_BUG_ON(!mm->context.slb_addr_limit);
-	get_paca()->mm_ctx_slb_addr_limit = mm->context.slb_addr_limit;
-	memcpy(&get_paca()->mm_ctx_low_slices_psize,
-	       &context->low_slices_psize, sizeof(context->low_slices_psize));
-	memcpy(&get_paca()->mm_ctx_high_slices_psize,
-	       &context->high_slices_psize, TASK_SLICE_ARRAY_SZ(mm));
+	VM_BUG_ON(!mm_ctx_slb_addr_limit(context));
+	get_paca()->mm_ctx_slb_addr_limit = mm_ctx_slb_addr_limit(context);
+	memcpy(&get_paca()->mm_ctx_low_slices_psize, mm_ctx_low_slices(context),
+	       LOW_SLICE_ARRAY_SZ);
+	memcpy(&get_paca()->mm_ctx_high_slices_psize, mm_ctx_high_slices(context),
+	       TASK_SLICE_ARRAY_SZ(context));
 #else /* CONFIG_PPC_MM_SLICES */
 	get_paca()->mm_ctx_user_psize = context->user_psize;
 	get_paca()->mm_ctx_sllp = context->sllp;

arch/powerpc/mm/hash_utils_64.c

@@ -1142,7 +1142,7 @@ void demote_segment_4k(struct mm_struct *mm, unsigned long addr)
  */
 static int subpage_protection(struct mm_struct *mm, unsigned long ea)
 {
-	struct subpage_prot_table *spt = &mm->context.spt;
+	struct subpage_prot_table *spt = mm_ctx_subpage_prot(&mm->context);
 	u32 spp = 0;
 	u32 **sbpm, *sbpp;
 
@@ -1465,7 +1465,7 @@ static bool should_hash_preload(struct mm_struct *mm, unsigned long ea)
 	int psize = get_slice_psize(mm, ea);
 
 	/* We only prefault standard pages for now */
-	if (unlikely(psize != mm->context.user_psize))
+	if (unlikely(psize != mm_ctx_user_psize(&mm->context)))
 		return false;
 
 	/*
@@ -1544,7 +1544,7 @@ void hash_preload(struct mm_struct *mm, unsigned long ea,
 
 	/* Hash it in */
 #ifdef CONFIG_PPC_64K_PAGES
-	if (mm->context.user_psize == MMU_PAGE_64K)
+	if (mm_ctx_user_psize(&mm->context) == MMU_PAGE_64K)
 		rc = __hash_page_64K(ea, access, vsid, ptep, trap,
 				     update_flags, ssize);
 	else
@@ -1557,8 +1557,8 @@ void hash_preload(struct mm_struct *mm, unsigned long ea,
 	 */
 	if (rc == -1)
 		hash_failure_debug(ea, access, vsid, trap, ssize,
-				   mm->context.user_psize,
-				   mm->context.user_psize,
+				   mm_ctx_user_psize(&mm->context),
+				   mm_ctx_user_psize(&mm->context),
 				   pte_val(*ptep));
 out_exit:
 	local_irq_restore(flags);

arch/powerpc/mm/slb.c

@@ -739,7 +739,7 @@ static long slb_allocate_user(struct mm_struct *mm, unsigned long ea)
 	 * consider this as bad access if we take a SLB miss
 	 * on an address above addr limit.
 	 */
-	if (ea >= mm->context.slb_addr_limit)
+	if (ea >= mm_ctx_slb_addr_limit(&mm->context))
 		return -EFAULT;
 
 	context = get_user_context(&mm->context, ea);

arch/powerpc/mm/slice.c

@@ -101,7 +101,7 @@ static int slice_area_is_free(struct mm_struct *mm, unsigned long addr,
 {
 	struct vm_area_struct *vma;
 
-	if ((mm->context.slb_addr_limit - len) < addr)
+	if ((mm_ctx_slb_addr_limit(&mm->context) - len) < addr)
 		return 0;
 	vma = find_vma(mm, addr);
 	return (!vma || (addr + len) <= vm_start_gap(vma));
@@ -155,15 +155,15 @@ static struct slice_mask *slice_mask_for_size(struct mm_struct *mm, int psize)
 {
 #ifdef CONFIG_PPC_64K_PAGES
 	if (psize == MMU_PAGE_64K)
-		return &mm->context.mask_64k;
+		return mm_ctx_slice_mask_64k(&mm->context);
 #endif
 	if (psize == MMU_PAGE_4K)
-		return &mm->context.mask_4k;
+		return mm_ctx_slice_mask_4k(&mm->context);
 #ifdef CONFIG_HUGETLB_PAGE
 	if (psize == MMU_PAGE_16M)
-		return &mm->context.mask_16m;
+		return mm_ctx_slice_mask_16m(&mm->context);
 	if (psize == MMU_PAGE_16G)
-		return &mm->context.mask_16g;
+		return mm_ctx_slice_mask_16g(&mm->context);
 #endif
 	BUG();
 }
@@ -253,7 +253,7 @@ static void slice_convert(struct mm_struct *mm,
 	 */
 	spin_lock_irqsave(&slice_convert_lock, flags);
 
-	lpsizes = mm->context.low_slices_psize;
+	lpsizes = mm_ctx_low_slices(&mm->context);
 	for (i = 0; i < SLICE_NUM_LOW; i++) {
 		if (!(mask->low_slices & (1u << i)))
 			continue;
@@ -272,8 +272,8 @@ static void slice_convert(struct mm_struct *mm,
 				(((unsigned long)psize) << (mask_index * 4));
 	}
 
-	hpsizes = mm->context.high_slices_psize;
-	for (i = 0; i < GET_HIGH_SLICE_INDEX(mm->context.slb_addr_limit); i++) {
+	hpsizes = mm_ctx_high_slices(&mm->context);
+	for (i = 0; i < GET_HIGH_SLICE_INDEX(mm_ctx_slb_addr_limit(&mm->context)); i++) {
 		if (!test_bit(i, mask->high_slices))
 			continue;
 
@@ -292,8 +292,8 @@ static void slice_convert(struct mm_struct *mm,
 	}
 
 	slice_dbg(" lsps=%lx, hsps=%lx\n",
-		  (unsigned long)mm->context.low_slices_psize,
-		  (unsigned long)mm->context.high_slices_psize);
+		  (unsigned long)mm_ctx_low_slices(&mm->context),
+		  (unsigned long)mm_ctx_high_slices(&mm->context));
 
 	spin_unlock_irqrestore(&slice_convert_lock, flags);
 
@@ -393,7 +393,7 @@ static unsigned long slice_find_area_topdown(struct mm_struct *mm,
 	 * DEFAULT_MAP_WINDOW we should apply this.
 	 */
 	if (high_limit > DEFAULT_MAP_WINDOW)
-		addr += mm->context.slb_addr_limit - DEFAULT_MAP_WINDOW;
+		addr += mm_ctx_slb_addr_limit(&mm->context) - DEFAULT_MAP_WINDOW;
 
 	while (addr > min_addr) {
 		info.high_limit = addr;
@@ -505,20 +505,20 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
 			return -ENOMEM;
 	}
 
-	if (high_limit > mm->context.slb_addr_limit) {
+	if (high_limit > mm_ctx_slb_addr_limit(&mm->context)) {
 		/*
 		 * Increasing the slb_addr_limit does not require
 		 * slice mask cache to be recalculated because it should
 		 * be already initialised beyond the old address limit.
 		 */
-		mm->context.slb_addr_limit = high_limit;
+		mm_ctx_set_slb_addr_limit(&mm->context, high_limit);
 
 		on_each_cpu(slice_flush_segments, mm, 1);
 	}
 
 	/* Sanity checks */
 	BUG_ON(mm->task_size == 0);
-	BUG_ON(mm->context.slb_addr_limit == 0);
+	BUG_ON(mm_ctx_slb_addr_limit(&mm->context) == 0);
 	VM_BUG_ON(radix_enabled());
 
 	slice_dbg("slice_get_unmapped_area(mm=%p, psize=%d...\n", mm, psize);
@@ -696,7 +696,7 @@ unsigned long arch_get_unmapped_area(struct file *filp,
 				     unsigned long flags)
 {
 	return slice_get_unmapped_area(addr, len, flags,
-				       current->mm->context.user_psize, 0);
+				       mm_ctx_user_psize(&current->mm->context), 0);
 }
 
 unsigned long arch_get_unmapped_area_topdown(struct file *filp,
@@ -706,7 +706,7 @@ unsigned long arch_get_unmapped_area_topdown(struct file *filp,
 					     const unsigned long flags)
 {
 	return slice_get_unmapped_area(addr0, len, flags,
-				       current->mm->context.user_psize, 1);
+				       mm_ctx_user_psize(&current->mm->context), 1);
 }
 
 unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr)
@@ -717,10 +717,10 @@ unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr)
 	VM_BUG_ON(radix_enabled());
 
 	if (slice_addr_is_low(addr)) {
-		psizes = mm->context.low_slices_psize;
+		psizes = mm_ctx_low_slices(&mm->context);
 		index = GET_LOW_SLICE_INDEX(addr);
 	} else {
-		psizes = mm->context.high_slices_psize;
+		psizes = mm_ctx_high_slices(&mm->context);
 		index = GET_HIGH_SLICE_INDEX(addr);
 	}
 	mask_index = index & 0x1;
@@ -742,20 +742,19 @@ void slice_init_new_context_exec(struct mm_struct *mm)
 	 * duplicated.
 	 */
 #ifdef CONFIG_PPC64
-	mm->context.slb_addr_limit = DEFAULT_MAP_WINDOW_USER64;
+	mm_ctx_set_slb_addr_limit(&mm->context, DEFAULT_MAP_WINDOW_USER64);
 #else
 	mm->context.slb_addr_limit = DEFAULT_MAP_WINDOW;
 #endif
-
-	mm->context.user_psize = psize;
+	mm_ctx_set_user_psize(&mm->context, psize);
 
 	/*
 	 * Set all slice psizes to the default.
 	 */
-	lpsizes = mm->context.low_slices_psize;
+	lpsizes = mm_ctx_low_slices(&mm->context);
 	memset(lpsizes, (psize << 4) | psize, SLICE_NUM_LOW >> 1);
 
-	hpsizes = mm->context.high_slices_psize;
+	hpsizes = mm_ctx_high_slices(&mm->context);
 	memset(hpsizes, (psize << 4) | psize, SLICE_NUM_HIGH >> 1);
 
 	/*
@@ -777,7 +776,7 @@ void slice_setup_new_exec(void)
 	if (!is_32bit_task())
 		return;
 
-	mm->context.slb_addr_limit = DEFAULT_MAP_WINDOW;
+	mm_ctx_set_slb_addr_limit(&mm->context, DEFAULT_MAP_WINDOW);
 }
 #endif
 
@@ -816,7 +815,7 @@ int slice_is_hugepage_only_range(struct mm_struct *mm, unsigned long addr,
 			   unsigned long len)
 {
 	const struct slice_mask *maskp;
-	unsigned int psize = mm->context.user_psize;
+	unsigned int psize = mm_ctx_user_psize(&mm->context);
 
 	VM_BUG_ON(radix_enabled());