patch-2.4.0-test12 linux/arch/parisc/mm/kmap.c

• Lines: 144
• Date: Tue Dec 5 12:29:39 2000
• Orig file: v2.4.0-test11/linux/arch/parisc/mm/kmap.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.0-test11/linux/arch/parisc/mm/kmap.c linux/arch/parisc/mm/kmap.c
@@ -0,0 +1,143 @@
+/*
+** Stolen mostly from arch/parisc/kernel/pci-dma.c
+*/
+
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/pci.h>
+
+#include <linux/malloc.h>
+#include <linux/vmalloc.h>
+
+#include <asm/uaccess.h>
+#include <asm/pgalloc.h>
+
+#include <asm/io.h>
+#include <asm/page.h>		/* get_order */
+
+#undef flush_cache_all
+#define flush_cache_all flush_all_caches
+
+typedef void (*pte_iterator_t) (pte_t * pte, unsigned long arg);
+
+#if 0
+/* XXX This routine could be used with iterate_page() to replace
+ * unmap_uncached_page() and save a little code space but I didn't
+ * do that since I'm not certain whether this is the right path. -PB
+ */
+static void unmap_cached_pte(pte_t * pte, unsigned long arg)
+{
+	pte_t page = *pte;
+	pte_clear(pte);
+	if (!pte_none(page)) {
+		if (pte_present(page)) {
+			unsigned long map_nr = pte_pagenr(page);
+			if (map_nr < max_mapnr)
+				__free_page(mem_map + map_nr);
+		} else {
+			printk(KERN_CRIT
+			       "Whee.. Swapped out page in kernel page table\n");
+		}
+	}
+}
+#endif
+
+/* These two routines should probably check a few things... */
+static void set_uncached(pte_t * pte, unsigned long arg)
+{
+	pte_val(*pte) |= _PAGE_NO_CACHE;
+}
+
+static void set_cached(pte_t * pte, unsigned long arg)
+{
+	pte_val(*pte) &= ~_PAGE_NO_CACHE;
+}
+
+static inline void iterate_pte(pmd_t * pmd, unsigned long address,
+			       unsigned long size, pte_iterator_t op,
+			       unsigned long arg)
+{
+	pte_t *pte;
+	unsigned long end;
+
+	if (pmd_none(*pmd))
+		return;
+	if (pmd_bad(*pmd)) {
+		pmd_ERROR(*pmd);
+		pmd_clear(pmd);
+		return;
+	}
+	pte = pte_offset(pmd, address);
+	address &= ~PMD_MASK;
+	end = address + size;
+	if (end > PMD_SIZE)
+		end = PMD_SIZE;
+	do {
+		op(pte, arg);
+		address += PAGE_SIZE;
+		pte++;
+	} while (address < end);
+}
+
+static inline void iterate_pmd(pgd_t * dir, unsigned long address,
+			       unsigned long size, pte_iterator_t op,
+			       unsigned long arg)
+{
+	pmd_t *pmd;
+	unsigned long end;
+
+	if (pgd_none(*dir))
+		return;
+	if (pgd_bad(*dir)) {
+		pgd_ERROR(*dir);
+		pgd_clear(dir);
+		return;
+	}
+	pmd = pmd_offset(dir, address);
+	address &= ~PGDIR_MASK;
+	end = address + size;
+	if (end > PGDIR_SIZE)
+		end = PGDIR_SIZE;
+	do {
+		iterate_pte(pmd, address, end - address, op, arg);
+		address = (address + PMD_SIZE) & PMD_MASK;
+		pmd++;
+	} while (address < end);
+}
+
+static void iterate_pages(unsigned long address, unsigned long size,
+			  pte_iterator_t op, unsigned long arg)
+{
+	pgd_t *dir;
+	unsigned long end = address + size;
+
+	dir = pgd_offset_k(address);
+	flush_cache_all();
+	do {
+		iterate_pmd(dir, address, end - address, op, arg);
+		address = (address + PGDIR_SIZE) & PGDIR_MASK;
+		dir++;
+	} while (address && (address < end));
+	flush_tlb_all();
+}
+
+void
+kernel_set_cachemode(unsigned long vaddr, unsigned long size, int what)
+{
+	switch (what) {
+	case IOMAP_FULL_CACHING:
+		iterate_pages(vaddr, size, set_cached, 0);
+		flush_tlb_range(&init_mm, vaddr, size);
+		break;
+	case IOMAP_NOCACHE_SER:
+		iterate_pages(vaddr, size, set_uncached, 0);
+		flush_tlb_range(&init_mm, vaddr, size);
+		break;
+	default:
+		printk(KERN_CRIT
+		       "kernel_set_cachemode mode %d not understood\n",
+		       what);
+		break;
+	}
+}