patch-2.4.10 linux/arch/ppc/mm/tlb.c

• Lines: 163
• Date: Tue Aug 28 06:58:33 2001
• Orig file: v2.4.9/linux/arch/ppc/mm/tlb.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.9/linux/arch/ppc/mm/tlb.c linux/arch/ppc/mm/tlb.c
@@ -0,0 +1,162 @@
+/*
+ * BK Id: %F% %I% %G% %U% %#%
+ */
+/*
+ * This file contains the routines for TLB flushing.
+ * On machines where the MMU uses a hash table to store virtual to
+ * physical translations, these routines flush entries from the the
+ * hash table also.
+ *  -- paulus
+ * 
+ *  Derived from arch/ppc/mm/init.c:
+ *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
+ *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
+ *    Copyright (C) 1996 Paul Mackerras
+ *  Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
+ *
+ *  Derived from "arch/i386/mm/init.c"
+ *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version
+ *  2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+
+#include "mmu_decl.h"
+
+/*
+ * TLB flushing:
+ *
+ *  - flush_tlb_all() flushes all processes TLBs
+ *  - flush_tlb_mm(mm) flushes the specified mm context TLB's
+ *  - flush_tlb_page(vma, vmaddr) flushes one page
+ *  - flush_tlb_range(mm, start, end) flushes a range of pages
+ *
+ * since the hardware hash table functions as an extension of the
+ * tlb as far as the linux tables are concerned, flush it too.
+ *    -- Cort
+ */
+
+/*
+ * Flush all tlb/hash table entries (except perhaps for those
+ * mapping RAM starting at PAGE_OFFSET, since they never change).
+ */
+void
+local_flush_tlb_all(void)
+{
+	/* aargh!!! */
+	/*
+	 * Just flush the kernel part of the address space, that's
+	 * all that the current callers of this require.
+	 * Eventually I hope to persuade the powers that be that
+	 * we can and should dispense with flush_tlb_all().
+	 *  -- paulus.
+	 */
+	local_flush_tlb_range(&init_mm, TASK_SIZE, ~0UL);
+
+#ifdef CONFIG_SMP
+	smp_send_tlb_invalidate(0);
+#endif /* CONFIG_SMP */
+}
+
+/*
+ * Flush all the (user) entries for the address space described
+ * by mm.  We can't rely on mm->mmap describing all the entries
+ * that might be in the hash table.
+ */
+void
+local_flush_tlb_mm(struct mm_struct *mm)
+{
+	if (Hash == 0) {
+		_tlbia();
+		return;
+	}
+
+	if (mm->map_count) {
+		struct vm_area_struct *mp;
+		for (mp = mm->mmap; mp != NULL; mp = mp->vm_next)
+			local_flush_tlb_range(mm, mp->vm_start, mp->vm_end);
+	} else
+		local_flush_tlb_range(mm, 0, TASK_SIZE);
+
+#ifdef CONFIG_SMP
+	smp_send_tlb_invalidate(0);
+#endif	
+}
+
+void
+local_flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
+{
+	struct mm_struct *mm;
+	pmd_t *pmd;
+	pte_t *pte;
+
+	if (Hash == 0) {
+		_tlbie(vmaddr);
+		return;
+	}
+	mm = (vmaddr < TASK_SIZE)? vma->vm_mm: &init_mm;
+	pmd = pmd_offset(pgd_offset(mm, vmaddr), vmaddr);
+	if (!pmd_none(*pmd)) {
+		pte = pte_offset(pmd, vmaddr);
+		if (pte_val(*pte) & _PAGE_HASHPTE)
+			flush_hash_page(mm->context, vmaddr, pte);
+	}
+#ifdef CONFIG_SMP
+	smp_send_tlb_invalidate(0);
+#endif	
+}
+
+
+/*
+ * For each address in the range, find the pte for the address
+ * and check _PAGE_HASHPTE bit; if it is set, find and destroy
+ * the corresponding HPTE.
+ */
+void
+local_flush_tlb_range(struct mm_struct *mm, unsigned long start, unsigned long end)
+{
+	pmd_t *pmd;
+	pte_t *pte;
+	unsigned long pmd_end;
+	unsigned int ctx = mm->context;
+
+	if (Hash == 0) {
+		_tlbia();
+		return;
+	}
+	start &= PAGE_MASK;
+	if (start >= end)
+		return;
+	pmd = pmd_offset(pgd_offset(mm, start), start);
+	do {
+		pmd_end = (start + PGDIR_SIZE) & PGDIR_MASK;
+		if (!pmd_none(*pmd)) {
+			if (!pmd_end || pmd_end > end)
+				pmd_end = end;
+			pte = pte_offset(pmd, start);
+			do {
+				if ((pte_val(*pte) & _PAGE_HASHPTE) != 0)
+					flush_hash_page(ctx, start, pte);
+				start += PAGE_SIZE;
+				++pte;
+			} while (start && start < pmd_end);
+		} else {
+			start = pmd_end;
+		}
+		++pmd;
+	} while (start && start < end);
+
+#ifdef CONFIG_SMP
+	smp_send_tlb_invalidate(0);
+#endif	
+}