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!

arch/frv/mm/dma-alloc.c

@@ -0,0 +1,188 @@
+/* dma-alloc.c: consistent DMA memory allocation
+ *
+ * Derived from arch/ppc/mm/cachemap.c
+ *
+ *  PowerPC version derived from arch/arm/mm/consistent.c
+ *    Copyright (C) 2001 Dan Malek (dmalek@jlc.net)
+ *
+ *  linux/arch/arm/mm/consistent.c
+ *
+ *  Copyright (C) 2000 Russell King
+ *
+ * Consistent memory allocators.  Used for DMA devices that want to
+ * share uncached memory with the processor core.  The function return
+ * is the virtual address and 'dma_handle' is the physical address.
+ * Mostly stolen from the ARM port, with some changes for PowerPC.
+ *						-- Dan
+ * Modified for 36-bit support.  -Matt
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/ptrace.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/stddef.h>
+#include <linux/vmalloc.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+
+#include <asm/pgalloc.h>
+#include <asm/io.h>
+#include <asm/hardirq.h>
+#include <asm/mmu_context.h>
+#include <asm/pgtable.h>
+#include <asm/mmu.h>
+#include <asm/uaccess.h>
+#include <asm/smp.h>
+
+static int map_page(unsigned long va, unsigned long pa, pgprot_t prot)
+{
+	pgd_t *pge;
+	pud_t *pue;
+	pmd_t *pme;
+	pte_t *pte;
+	int err = -ENOMEM;
+
+	spin_lock(&init_mm.page_table_lock);
+
+	/* Use upper 10 bits of VA to index the first level map */
+	pge = pgd_offset_k(va);
+	pue = pud_offset(pge, va);
+	pme = pmd_offset(pue, va);
+
+	/* Use middle 10 bits of VA to index the second-level map */
+	pte = pte_alloc_kernel(&init_mm, pme, va);
+	if (pte != 0) {
+		err = 0;
+		set_pte(pte, mk_pte_phys(pa & PAGE_MASK, prot));
+	}
+
+	spin_unlock(&init_mm.page_table_lock);
+	return err;
+}
+
+/*
+ * This function will allocate the requested contiguous pages and
+ * map them into the kernel's vmalloc() space.  This is done so we
+ * get unique mapping for these pages, outside of the kernel's 1:1
+ * virtual:physical mapping.  This is necessary so we can cover large
+ * portions of the kernel with single large page TLB entries, and
+ * still get unique uncached pages for consistent DMA.
+ */
+void *consistent_alloc(int gfp, size_t size, dma_addr_t *dma_handle)
+{
+	struct vm_struct *area;
+	unsigned long page, va, pa;
+	void *ret;
+	int order, err, i;
+
+	if (in_interrupt())
+		BUG();
+
+	/* only allocate page size areas */
+	size = PAGE_ALIGN(size);
+	order = get_order(size);
+
+	page = __get_free_pages(gfp, order);
+	if (!page) {
+		BUG();
+		return NULL;
+	}
+
+	/* allocate some common virtual space to map the new pages */
+	area = get_vm_area(size, VM_ALLOC);
+	if (area == 0) {
+		free_pages(page, order);
+		return NULL;
+	}
+	va = VMALLOC_VMADDR(area->addr);
+	ret = (void *) va;
+
+	/* this gives us the real physical address of the first page */
+	*dma_handle = pa = virt_to_bus((void *) page);
+
+	/* set refcount=1 on all pages in an order>0 allocation so that vfree() will actually free
+	 * all pages that were allocated.
+	 */
+	if (order > 0) {
+		struct page *rpage = virt_to_page(page);
+
+		for (i = 1; i < (1 << order); i++)
+			set_page_count(rpage + i, 1);
+	}
+
+	err = 0;
+	for (i = 0; i < size && err == 0; i += PAGE_SIZE)
+		err = map_page(va + i, pa + i, PAGE_KERNEL_NOCACHE);
+
+	if (err) {
+		vfree((void *) va);
+		return NULL;
+	}
+
+	/* we need to ensure that there are no cachelines in use, or worse dirty in this area
+	 * - can't do until after virtual address mappings are created
+	 */
+	frv_cache_invalidate(va, va + size);
+
+	return ret;
+}
+
+/*
+ * free page(s) as defined by the above mapping.
+ */
+void consistent_free(void *vaddr)
+{
+	if (in_interrupt())
+		BUG();
+	vfree(vaddr);
+}
+
+/*
+ * make an area consistent.
+ */
+void consistent_sync(void *vaddr, size_t size, int direction)
+{
+	unsigned long start = (unsigned long) vaddr;
+	unsigned long end   = start + size;
+
+	switch (direction) {
+	case PCI_DMA_NONE:
+		BUG();
+	case PCI_DMA_FROMDEVICE:	/* invalidate only */
+		frv_cache_invalidate(start, end);
+		break;
+	case PCI_DMA_TODEVICE:		/* writeback only */
+		frv_dcache_writeback(start, end);
+		break;
+	case PCI_DMA_BIDIRECTIONAL:	/* writeback and invalidate */
+		frv_dcache_writeback(start, end);
+		break;
+	}
+}
+
+/*
+ * consistent_sync_page make a page are consistent. identical
+ * to consistent_sync, but takes a struct page instead of a virtual address
+ */
+
+void consistent_sync_page(struct page *page, unsigned long offset,
+			  size_t size, int direction)
+{
+	void *start;
+
+	start = page_address(page) + offset;
+	consistent_sync(start, size, direction);
+}