Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
diff --git a/arch/sh/mm/pg-sh4.c b/arch/sh/mm/pg-sh4.c
new file mode 100644
index 0000000..e5907c7
--- /dev/null
+++ b/arch/sh/mm/pg-sh4.c
@@ -0,0 +1,122 @@
+/*
+ * arch/sh/mm/pg-sh4.c
+ *
+ * Copyright (C) 1999, 2000, 2002  Niibe Yutaka
+ * Copyright (C) 2002  Paul Mundt
+ *
+ * Released under the terms of the GNU GPL v2.0.
+ */
+#include <linux/config.h>
+#include <linux/init.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/threads.h>
+#include <asm/addrspace.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/processor.h>
+#include <asm/cache.h>
+#include <asm/io.h>
+#include <asm/uaccess.h>
+#include <asm/pgalloc.h>
+#include <asm/mmu_context.h>
+#include <asm/cacheflush.h>
+
+extern struct semaphore p3map_sem[];
+
+/*
+ * clear_user_page
+ * @to: P1 address
+ * @address: U0 address to be mapped
+ * @page: page (virt_to_page(to))
+ */
+void clear_user_page(void *to, unsigned long address, struct page *page)
+{
+	__set_bit(PG_mapped, &page->flags);
+	if (((address ^ (unsigned long)to) & CACHE_ALIAS) == 0)
+		clear_page(to);
+	else {
+		pgprot_t pgprot = __pgprot(_PAGE_PRESENT | 
+					   _PAGE_RW | _PAGE_CACHABLE |
+					   _PAGE_DIRTY | _PAGE_ACCESSED | 
+					   _PAGE_HW_SHARED | _PAGE_FLAGS_HARD);
+		unsigned long phys_addr = PHYSADDR(to);
+		unsigned long p3_addr = P3SEG + (address & CACHE_ALIAS);
+		pgd_t *dir = pgd_offset_k(p3_addr);
+		pmd_t *pmd = pmd_offset(dir, p3_addr);
+		pte_t *pte = pte_offset_kernel(pmd, p3_addr);
+		pte_t entry;
+		unsigned long flags;
+
+		entry = pfn_pte(phys_addr >> PAGE_SHIFT, pgprot);
+		down(&p3map_sem[(address & CACHE_ALIAS)>>12]);
+		set_pte(pte, entry);
+		local_irq_save(flags);
+		__flush_tlb_page(get_asid(), p3_addr);
+		local_irq_restore(flags);
+		update_mmu_cache(NULL, p3_addr, entry);
+		__clear_user_page((void *)p3_addr, to);
+		pte_clear(&init_mm, p3_addr, pte);
+		up(&p3map_sem[(address & CACHE_ALIAS)>>12]);
+	}
+}
+
+/*
+ * copy_user_page
+ * @to: P1 address
+ * @from: P1 address
+ * @address: U0 address to be mapped
+ * @page: page (virt_to_page(to))
+ */
+void copy_user_page(void *to, void *from, unsigned long address, 
+		    struct page *page)
+{
+	__set_bit(PG_mapped, &page->flags);
+	if (((address ^ (unsigned long)to) & CACHE_ALIAS) == 0)
+		copy_page(to, from);
+	else {
+		pgprot_t pgprot = __pgprot(_PAGE_PRESENT | 
+					   _PAGE_RW | _PAGE_CACHABLE |
+					   _PAGE_DIRTY | _PAGE_ACCESSED | 
+					   _PAGE_HW_SHARED | _PAGE_FLAGS_HARD);
+		unsigned long phys_addr = PHYSADDR(to);
+		unsigned long p3_addr = P3SEG + (address & CACHE_ALIAS);
+		pgd_t *dir = pgd_offset_k(p3_addr);
+		pmd_t *pmd = pmd_offset(dir, p3_addr);
+		pte_t *pte = pte_offset_kernel(pmd, p3_addr);
+		pte_t entry;
+		unsigned long flags;
+
+		entry = pfn_pte(phys_addr >> PAGE_SHIFT, pgprot);
+		down(&p3map_sem[(address & CACHE_ALIAS)>>12]);
+		set_pte(pte, entry);
+		local_irq_save(flags);
+		__flush_tlb_page(get_asid(), p3_addr);
+		local_irq_restore(flags);
+		update_mmu_cache(NULL, p3_addr, entry);
+		__copy_user_page((void *)p3_addr, from, to);
+		pte_clear(&init_mm, p3_addr, pte);
+		up(&p3map_sem[(address & CACHE_ALIAS)>>12]);
+	}
+}
+
+/*
+ * For SH-4, we have our own implementation for ptep_get_and_clear
+ */
+inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
+{
+	pte_t pte = *ptep;
+
+	pte_clear(mm, addr, ptep);
+	if (!pte_not_present(pte)) {
+		unsigned long pfn = pte_pfn(pte);
+		if (pfn_valid(pfn)) {
+			struct page *page = pfn_to_page(pfn);
+			struct address_space *mapping = page_mapping(page);
+			if (!mapping || !mapping_writably_mapped(mapping))
+				__clear_bit(PG_mapped, &page->flags);
+		}
+	}
+	return pte;
+}
+