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-rw-r--r--arch/arm/mm/consistent.c514
1 files changed, 0 insertions, 514 deletions
diff --git a/arch/arm/mm/consistent.c b/arch/arm/mm/consistent.c
deleted file mode 100644
index db7b3e38ef1..00000000000
--- a/arch/arm/mm/consistent.c
+++ /dev/null
@@ -1,514 +0,0 @@
-/*
- * linux/arch/arm/mm/consistent.c
- *
- * Copyright (C) 2000-2004 Russell King
- *
- * 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.
- *
- * DMA uncached mapping support.
- */
-#include <linux/module.h>
-#include <linux/mm.h>
-#include <linux/slab.h>
-#include <linux/errno.h>
-#include <linux/list.h>
-#include <linux/init.h>
-#include <linux/device.h>
-#include <linux/dma-mapping.h>
-
-#include <asm/memory.h>
-#include <asm/cacheflush.h>
-#include <asm/tlbflush.h>
-#include <asm/sizes.h>
-
-/* Sanity check size */
-#if (CONSISTENT_DMA_SIZE % SZ_2M)
-#error "CONSISTENT_DMA_SIZE must be multiple of 2MiB"
-#endif
-
-#define CONSISTENT_END (0xffe00000)
-#define CONSISTENT_BASE (CONSISTENT_END - CONSISTENT_DMA_SIZE)
-
-#define CONSISTENT_OFFSET(x) (((unsigned long)(x) - CONSISTENT_BASE) >> PAGE_SHIFT)
-#define CONSISTENT_PTE_INDEX(x) (((unsigned long)(x) - CONSISTENT_BASE) >> PGDIR_SHIFT)
-#define NUM_CONSISTENT_PTES (CONSISTENT_DMA_SIZE >> PGDIR_SHIFT)
-
-
-/*
- * These are the page tables (2MB each) covering uncached, DMA consistent allocations
- */
-static pte_t *consistent_pte[NUM_CONSISTENT_PTES];
-static DEFINE_SPINLOCK(consistent_lock);
-
-/*
- * VM region handling support.
- *
- * This should become something generic, handling VM region allocations for
- * vmalloc and similar (ioremap, module space, etc).
- *
- * I envisage vmalloc()'s supporting vm_struct becoming:
- *
- * struct vm_struct {
- * struct vm_region region;
- * unsigned long flags;
- * struct page **pages;
- * unsigned int nr_pages;
- * unsigned long phys_addr;
- * };
- *
- * get_vm_area() would then call vm_region_alloc with an appropriate
- * struct vm_region head (eg):
- *
- * struct vm_region vmalloc_head = {
- * .vm_list = LIST_HEAD_INIT(vmalloc_head.vm_list),
- * .vm_start = VMALLOC_START,
- * .vm_end = VMALLOC_END,
- * };
- *
- * However, vmalloc_head.vm_start is variable (typically, it is dependent on
- * the amount of RAM found at boot time.) I would imagine that get_vm_area()
- * would have to initialise this each time prior to calling vm_region_alloc().
- */
-struct vm_region {
- struct list_head vm_list;
- unsigned long vm_start;
- unsigned long vm_end;
- struct page *vm_pages;
- int vm_active;
-};
-
-static struct vm_region consistent_head = {
- .vm_list = LIST_HEAD_INIT(consistent_head.vm_list),
- .vm_start = CONSISTENT_BASE,
- .vm_end = CONSISTENT_END,
-};
-
-static struct vm_region *
-vm_region_alloc(struct vm_region *head, size_t size, gfp_t gfp)
-{
- unsigned long addr = head->vm_start, end = head->vm_end - size;
- unsigned long flags;
- struct vm_region *c, *new;
-
- new = kmalloc(sizeof(struct vm_region), gfp);
- if (!new)
- goto out;
-
- spin_lock_irqsave(&consistent_lock, flags);
-
- list_for_each_entry(c, &head->vm_list, vm_list) {
- if ((addr + size) < addr)
- goto nospc;
- if ((addr + size) <= c->vm_start)
- goto found;
- addr = c->vm_end;
- if (addr > end)
- goto nospc;
- }
-
- found:
- /*
- * Insert this entry _before_ the one we found.
- */
- list_add_tail(&new->vm_list, &c->vm_list);
- new->vm_start = addr;
- new->vm_end = addr + size;
- new->vm_active = 1;
-
- spin_unlock_irqrestore(&consistent_lock, flags);
- return new;
-
- nospc:
- spin_unlock_irqrestore(&consistent_lock, flags);
- kfree(new);
- out:
- return NULL;
-}
-
-static struct vm_region *vm_region_find(struct vm_region *head, unsigned long addr)
-{
- struct vm_region *c;
-
- list_for_each_entry(c, &head->vm_list, vm_list) {
- if (c->vm_active && c->vm_start == addr)
- goto out;
- }
- c = NULL;
- out:
- return c;
-}
-
-#ifdef CONFIG_HUGETLB_PAGE
-#error ARM Coherent DMA allocator does not (yet) support huge TLB
-#endif
-
-static void *
-__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp,
- pgprot_t prot)
-{
- struct page *page;
- struct vm_region *c;
- unsigned long order;
- u64 mask = ISA_DMA_THRESHOLD, limit;
-
- if (!consistent_pte[0]) {
- printk(KERN_ERR "%s: not initialised\n", __func__);
- dump_stack();
- return NULL;
- }
-
- if (dev) {
- mask = dev->coherent_dma_mask;
-
- /*
- * Sanity check the DMA mask - it must be non-zero, and
- * must be able to be satisfied by a DMA allocation.
- */
- if (mask == 0) {
- dev_warn(dev, "coherent DMA mask is unset\n");
- goto no_page;
- }
-
- if ((~mask) & ISA_DMA_THRESHOLD) {
- dev_warn(dev, "coherent DMA mask %#llx is smaller "
- "than system GFP_DMA mask %#llx\n",
- mask, (unsigned long long)ISA_DMA_THRESHOLD);
- goto no_page;
- }
- }
-
- /*
- * Sanity check the allocation size.
- */
- size = PAGE_ALIGN(size);
- limit = (mask + 1) & ~mask;
- if ((limit && size >= limit) ||
- size >= (CONSISTENT_END - CONSISTENT_BASE)) {
- printk(KERN_WARNING "coherent allocation too big "
- "(requested %#x mask %#llx)\n", size, mask);
- goto no_page;
- }
-
- order = get_order(size);
-
- if (mask != 0xffffffff)
- gfp |= GFP_DMA;
-
- page = alloc_pages(gfp, order);
- if (!page)
- goto no_page;
-
- /*
- * Invalidate any data that might be lurking in the
- * kernel direct-mapped region for device DMA.
- */
- {
- void *ptr = page_address(page);
- memset(ptr, 0, size);
- dmac_flush_range(ptr, ptr + size);
- outer_flush_range(__pa(ptr), __pa(ptr) + size);
- }
-
- /*
- * Allocate a virtual address in the consistent mapping region.
- */
- c = vm_region_alloc(&consistent_head, size,
- gfp & ~(__GFP_DMA | __GFP_HIGHMEM));
- if (c) {
- pte_t *pte;
- struct page *end = page + (1 << order);
- int idx = CONSISTENT_PTE_INDEX(c->vm_start);
- u32 off = CONSISTENT_OFFSET(c->vm_start) & (PTRS_PER_PTE-1);
-
- pte = consistent_pte[idx] + off;
- c->vm_pages = page;
-
- split_page(page, order);
-
- /*
- * Set the "dma handle"
- */
- *handle = page_to_dma(dev, page);
-
- do {
- BUG_ON(!pte_none(*pte));
-
- /*
- * x86 does not mark the pages reserved...
- */
- SetPageReserved(page);
- set_pte_ext(pte, mk_pte(page, prot), 0);
- page++;
- pte++;
- off++;
- if (off >= PTRS_PER_PTE) {
- off = 0;
- pte = consistent_pte[++idx];
- }
- } while (size -= PAGE_SIZE);
-
- /*
- * Free the otherwise unused pages.
- */
- while (page < end) {
- __free_page(page);
- page++;
- }
-
- return (void *)c->vm_start;
- }
-
- if (page)
- __free_pages(page, order);
- no_page:
- *handle = ~0;
- return NULL;
-}
-
-/*
- * Allocate DMA-coherent memory space and return both the kernel remapped
- * virtual and bus address for that space.
- */
-void *
-dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp)
-{
- void *memory;
-
- if (dma_alloc_from_coherent(dev, size, handle, &memory))
- return memory;
-
- if (arch_is_coherent()) {
- void *virt;
-
- virt = kmalloc(size, gfp);
- if (!virt)
- return NULL;
- *handle = virt_to_dma(dev, virt);
-
- return virt;
- }
-
- return __dma_alloc(dev, size, handle, gfp,
- pgprot_noncached(pgprot_kernel));
-}
-EXPORT_SYMBOL(dma_alloc_coherent);
-
-/*
- * Allocate a writecombining region, in much the same way as
- * dma_alloc_coherent above.
- */
-void *
-dma_alloc_writecombine(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp)
-{
- return __dma_alloc(dev, size, handle, gfp,
- pgprot_writecombine(pgprot_kernel));
-}
-EXPORT_SYMBOL(dma_alloc_writecombine);
-
-static int dma_mmap(struct device *dev, struct vm_area_struct *vma,
- void *cpu_addr, dma_addr_t dma_addr, size_t size)
-{
- unsigned long flags, user_size, kern_size;
- struct vm_region *c;
- int ret = -ENXIO;
-
- user_size = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
-
- spin_lock_irqsave(&consistent_lock, flags);
- c = vm_region_find(&consistent_head, (unsigned long)cpu_addr);
- spin_unlock_irqrestore(&consistent_lock, flags);
-
- if (c) {
- unsigned long off = vma->vm_pgoff;
-
- kern_size = (c->vm_end - c->vm_start) >> PAGE_SHIFT;
-
- if (off < kern_size &&
- user_size <= (kern_size - off)) {
- ret = remap_pfn_range(vma, vma->vm_start,
- page_to_pfn(c->vm_pages) + off,
- user_size << PAGE_SHIFT,
- vma->vm_page_prot);
- }
- }
-
- return ret;
-}
-
-int dma_mmap_coherent(struct device *dev, struct vm_area_struct *vma,
- void *cpu_addr, dma_addr_t dma_addr, size_t size)
-{
- vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
- return dma_mmap(dev, vma, cpu_addr, dma_addr, size);
-}
-EXPORT_SYMBOL(dma_mmap_coherent);
-
-int dma_mmap_writecombine(struct device *dev, struct vm_area_struct *vma,
- void *cpu_addr, dma_addr_t dma_addr, size_t size)
-{
- vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
- return dma_mmap(dev, vma, cpu_addr, dma_addr, size);
-}
-EXPORT_SYMBOL(dma_mmap_writecombine);
-
-/*
- * free a page as defined by the above mapping.
- * Must not be called with IRQs disabled.
- */
-void dma_free_coherent(struct device *dev, size_t size, void *cpu_addr, dma_addr_t handle)
-{
- struct vm_region *c;
- unsigned long flags, addr;
- pte_t *ptep;
- int idx;
- u32 off;
-
- WARN_ON(irqs_disabled());
-
- if (dma_release_from_coherent(dev, get_order(size), cpu_addr))
- return;
-
- if (arch_is_coherent()) {
- kfree(cpu_addr);
- return;
- }
-
- size = PAGE_ALIGN(size);
-
- spin_lock_irqsave(&consistent_lock, flags);
- c = vm_region_find(&consistent_head, (unsigned long)cpu_addr);
- if (!c)
- goto no_area;
-
- c->vm_active = 0;
- spin_unlock_irqrestore(&consistent_lock, flags);
-
- if ((c->vm_end - c->vm_start) != size) {
- printk(KERN_ERR "%s: freeing wrong coherent size (%ld != %d)\n",
- __func__, c->vm_end - c->vm_start, size);
- dump_stack();
- size = c->vm_end - c->vm_start;
- }
-
- idx = CONSISTENT_PTE_INDEX(c->vm_start);
- off = CONSISTENT_OFFSET(c->vm_start) & (PTRS_PER_PTE-1);
- ptep = consistent_pte[idx] + off;
- addr = c->vm_start;
- do {
- pte_t pte = ptep_get_and_clear(&init_mm, addr, ptep);
- unsigned long pfn;
-
- ptep++;
- addr += PAGE_SIZE;
- off++;
- if (off >= PTRS_PER_PTE) {
- off = 0;
- ptep = consistent_pte[++idx];
- }
-
- if (!pte_none(pte) && pte_present(pte)) {
- pfn = pte_pfn(pte);
-
- if (pfn_valid(pfn)) {
- struct page *page = pfn_to_page(pfn);
-
- /*
- * x86 does not mark the pages reserved...
- */
- ClearPageReserved(page);
-
- __free_page(page);
- continue;
- }
- }
-
- printk(KERN_CRIT "%s: bad page in kernel page table\n",
- __func__);
- } while (size -= PAGE_SIZE);
-
- flush_tlb_kernel_range(c->vm_start, c->vm_end);
-
- spin_lock_irqsave(&consistent_lock, flags);
- list_del(&c->vm_list);
- spin_unlock_irqrestore(&consistent_lock, flags);
-
- kfree(c);
- return;
-
- no_area:
- spin_unlock_irqrestore(&consistent_lock, flags);
- printk(KERN_ERR "%s: trying to free invalid coherent area: %p\n",
- __func__, cpu_addr);
- dump_stack();
-}
-EXPORT_SYMBOL(dma_free_coherent);
-
-/*
- * Initialise the consistent memory allocation.
- */
-static int __init consistent_init(void)
-{
- pgd_t *pgd;
- pmd_t *pmd;
- pte_t *pte;
- int ret = 0, i = 0;
- u32 base = CONSISTENT_BASE;
-
- do {
- pgd = pgd_offset(&init_mm, base);
- pmd = pmd_alloc(&init_mm, pgd, base);
- if (!pmd) {
- printk(KERN_ERR "%s: no pmd tables\n", __func__);
- ret = -ENOMEM;
- break;
- }
- WARN_ON(!pmd_none(*pmd));
-
- pte = pte_alloc_kernel(pmd, base);
- if (!pte) {
- printk(KERN_ERR "%s: no pte tables\n", __func__);
- ret = -ENOMEM;
- break;
- }
-
- consistent_pte[i++] = pte;
- base += (1 << PGDIR_SHIFT);
- } while (base < CONSISTENT_END);
-
- return ret;
-}
-
-core_initcall(consistent_init);
-
-/*
- * Make an area consistent for devices.
- * Note: Drivers should NOT use this function directly, as it will break
- * platforms with CONFIG_DMABOUNCE.
- * Use the driver DMA support - see dma-mapping.h (dma_sync_*)
- */
-void dma_cache_maint(const void *start, size_t size, int direction)
-{
- const void *end = start + size;
-
- BUG_ON(!virt_addr_valid(start) || !virt_addr_valid(end - 1));
-
- switch (direction) {
- case DMA_FROM_DEVICE: /* invalidate only */
- dmac_inv_range(start, end);
- outer_inv_range(__pa(start), __pa(end));
- break;
- case DMA_TO_DEVICE: /* writeback only */
- dmac_clean_range(start, end);
- outer_clean_range(__pa(start), __pa(end));
- break;
- case DMA_BIDIRECTIONAL: /* writeback and invalidate */
- dmac_flush_range(start, end);
- outer_flush_range(__pa(start), __pa(end));
- break;
- default:
- BUG();
- }
-}
-EXPORT_SYMBOL(dma_cache_maint);
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