From 0ddbccd1187e12bf77e1f19d8b9dec700e09e734 Mon Sep 17 00:00:00 2001 From: Russell King Date: Thu, 25 Sep 2008 15:59:19 +0100 Subject: [ARM] dma: rename consistent.c to dma-mapping.c Signed-off-by: Russell King --- arch/arm/mm/Makefile | 2 +- arch/arm/mm/consistent.c | 514 ---------------------------------------------- arch/arm/mm/dma-mapping.c | 514 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 515 insertions(+), 515 deletions(-) delete mode 100644 arch/arm/mm/consistent.c create mode 100644 arch/arm/mm/dma-mapping.c diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile index 2e27a8c8372..480f78a3611 100644 --- a/arch/arm/mm/Makefile +++ b/arch/arm/mm/Makefile @@ -2,7 +2,7 @@ # Makefile for the linux arm-specific parts of the memory manager. # -obj-y := consistent.o extable.o fault.o init.o \ +obj-y := dma-mapping.o extable.o fault.o init.o \ iomap.o obj-$(CONFIG_MMU) += fault-armv.o flush.o ioremap.o mmap.o \ 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 -#include -#include -#include -#include -#include -#include -#include - -#include -#include -#include -#include - -/* 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); diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c new file mode 100644 index 00000000000..9f312248d5a --- /dev/null +++ b/arch/arm/mm/dma-mapping.c @@ -0,0 +1,514 @@ +/* + * linux/arch/arm/mm/dma-mapping.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 +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +/* 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); -- cgit v1.2.3