From 09f94287f7260e03bbeab497e743691fafcc22c3 Mon Sep 17 00:00:00 2001
From: "David S. Miller" <davem@davemloft.net>
Date: Tue, 31 Jan 2006 18:31:06 -0800
Subject: [PATCH] [SPARC64]: TSB refinements.

Move {init_new,destroy}_context() out of line.

Do not put huge pages into the TSB, only base page size translations.
There are some clever things we could do here, but for now let's be
correct instead of fancy.

Signed-off-by: David S. Miller <davem@davemloft.net>
---
 arch/sparc64/kernel/tsb.S         | 11 +++++++++++
 arch/sparc64/mm/tsb.c             | 28 +++++++++++++++++++++++++++
 include/asm-sparc64/mmu_context.h | 32 ++-----------------------------
 include/asm-sparc64/pgtable.h     |  4 ++++
 4 files changed, 45 insertions(+), 30 deletions(-)

diff --git a/arch/sparc64/kernel/tsb.S b/arch/sparc64/kernel/tsb.S
index 50752c5187..76f2c0b01f 100644
--- a/arch/sparc64/kernel/tsb.S
+++ b/arch/sparc64/kernel/tsb.S
@@ -55,6 +55,17 @@ tsb_reload:
 	brgez,a,pn	%g5, tsb_do_fault
 	 stx		%g0, [%g1]
 
+	/* If it is larger than the base page size, don't
+	 * bother putting it into the TSB.
+	 */
+	srlx		%g5, 32, %g2
+	sethi		%hi(_PAGE_ALL_SZ_BITS >> 32), %g4
+	sethi		%hi(_PAGE_SZBITS >> 32), %g7
+	and		%g2, %g4, %g2
+	cmp		%g2, %g7
+	bne,a,pn	%xcc, tsb_tlb_reload
+	 stx		%g0, [%g1]
+
 	TSB_WRITE(%g1, %g5, %g6)
 
 	/* Finally, load TLB and return from trap.  */
diff --git a/arch/sparc64/mm/tsb.c b/arch/sparc64/mm/tsb.c
index 15e8af58b1..2f84cef6c1 100644
--- a/arch/sparc64/mm/tsb.c
+++ b/arch/sparc64/mm/tsb.c
@@ -8,6 +8,7 @@
 #include <asm/page.h>
 #include <asm/tlbflush.h>
 #include <asm/tlb.h>
+#include <asm/mmu_context.h>
 
 #define TSB_ENTRY_ALIGNMENT	16
 
@@ -82,3 +83,30 @@ void flush_tsb_user(struct mmu_gather *mp)
 		}
 	}
 }
+
+int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
+{
+	unsigned long page = get_zeroed_page(GFP_KERNEL);
+
+	mm->context.sparc64_ctx_val = 0UL;
+	if (unlikely(!page))
+		return -ENOMEM;
+
+	mm->context.sparc64_tsb = (unsigned long *) page;
+
+	return 0;
+}
+
+void destroy_context(struct mm_struct *mm)
+{
+	free_page((unsigned long) mm->context.sparc64_tsb);
+
+	spin_lock(&ctx_alloc_lock);
+
+	if (CTX_VALID(mm->context)) {
+		unsigned long nr = CTX_NRBITS(mm->context);
+		mmu_context_bmap[nr>>6] &= ~(1UL << (nr & 63));
+	}
+
+	spin_unlock(&ctx_alloc_lock);
+}
diff --git a/include/asm-sparc64/mmu_context.h b/include/asm-sparc64/mmu_context.h
index 34640a370a..0dffb4ce8a 100644
--- a/include/asm-sparc64/mmu_context.h
+++ b/include/asm-sparc64/mmu_context.h
@@ -19,36 +19,8 @@ extern unsigned long tlb_context_cache;
 extern unsigned long mmu_context_bmap[];
 
 extern void get_new_mmu_context(struct mm_struct *mm);
-
-/* Initialize a new mmu context.  This is invoked when a new
- * address space instance (unique or shared) is instantiated.
- * This just needs to set mm->context to an invalid context.
- */
-#define init_new_context(__tsk, __mm)	\
-({	unsigned long __pg = get_zeroed_page(GFP_KERNEL); \
-	(__mm)->context.sparc64_ctx_val = 0UL; \
-	(__mm)->context.sparc64_tsb = \
-	  (unsigned long *) __pg; \
-	(__pg ? 0 : -ENOMEM); \
-})
-
-
-/* Destroy a dead context.  This occurs when mmput drops the
- * mm_users count to zero, the mmaps have been released, and
- * all the page tables have been flushed.  Our job is to destroy
- * any remaining processor-specific state, and in the sparc64
- * case this just means freeing up the mmu context ID held by
- * this task if valid.
- */
-#define destroy_context(__mm)					\
-do {	free_page((unsigned long)(__mm)->context.sparc64_tsb);	\
-	spin_lock(&ctx_alloc_lock);				\
-	if (CTX_VALID((__mm)->context)) {			\
-		unsigned long nr = CTX_NRBITS((__mm)->context);	\
-		mmu_context_bmap[nr>>6] &= ~(1UL << (nr & 63));	\
-	}							\
-	spin_unlock(&ctx_alloc_lock);				\
-} while(0)
+extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
+extern void destroy_context(struct mm_struct *mm);
 
 extern unsigned long tsb_context_switch(unsigned long pgd_pa, unsigned long *tsb);
 
diff --git a/include/asm-sparc64/pgtable.h b/include/asm-sparc64/pgtable.h
index 77ba0b6cc1..2b2ecd6104 100644
--- a/include/asm-sparc64/pgtable.h
+++ b/include/asm-sparc64/pgtable.h
@@ -116,6 +116,10 @@
 #define _PAGE_W		_AC(0x0000000000000002,UL) /* Writable               */
 #define _PAGE_G		_AC(0x0000000000000001,UL) /* Global                 */
 
+#define _PAGE_ALL_SZ_BITS	\
+	(_PAGE_SZ4MB | _PAGE_SZ512K | _PAGE_SZ64K | \
+	 _PAGE_SZ8K  | _PAGE_SZ32MB | _PAGE_SZ256MB)
+
 /* Here are the SpitFire software bits we use in the TTE's.
  *
  * WARNING: If you are going to try and start using some
-- 
2.39.5