From 695ae0af5a52df09dffcc2ce2d625d56ef36ce14 Mon Sep 17 00:00:00 2001 From: Russell King Date: Thu, 19 Nov 2009 16:31:39 +0000 Subject: ARM: dma-mapping: factor dma_free_coherent() common code We effectively have three implementations of dma_free_coherent() mixed up in the code; the incoherent MMU, coherent MMU and noMMU versions. The coherent MMU and noMMU versions are actually functionally identical. The incoherent MMU version is almost the same, but with the additional step of unmapping the secondary mapping. Separate out this additional step into __dma_free_remap() and simplify the resulting dma_free_coherent() code. Signed-off-by: Russell King Acked-by: Greg Ungerer --- arch/arm/mm/dma-mapping.c | 141 ++++++++++++++++++++++------------------------ 1 file changed, 68 insertions(+), 73 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 62b4240b34b..6b24e5ed85c 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -207,7 +207,70 @@ __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp, *handle = ~0; return NULL; } + +static void __dma_free_remap(void *cpu_addr, size_t size) +{ + struct arm_vmregion *c; + unsigned long addr; + pte_t *ptep; + int idx; + u32 off; + + c = arm_vmregion_find_remove(&consistent_head, (unsigned long)cpu_addr); + if (!c) { + printk(KERN_ERR "%s: trying to free invalid coherent area: %p\n", + __func__, cpu_addr); + dump_stack(); + return; + } + + 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); + 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); + + arm_vmregion_free(&consistent_head, c); +} + #else /* !CONFIG_MMU */ + static void * __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp, pgprot_t prot) @@ -224,6 +287,9 @@ __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp, *handle = page_to_dma(dev, page); return page_address(page); } + +#define __dma_free_remap(addr, size) do { } while (0) + #endif /* CONFIG_MMU */ /* @@ -317,15 +383,8 @@ EXPORT_SYMBOL(dma_mmap_writecombine); * free a page as defined by the above mapping. * Must not be called with IRQs disabled. */ -#ifdef CONFIG_MMU void dma_free_coherent(struct device *dev, size_t size, void *cpu_addr, dma_addr_t handle) { - struct arm_vmregion *c; - unsigned long addr; - pte_t *ptep; - int idx; - u32 off; - WARN_ON(irqs_disabled()); if (dma_release_from_coherent(dev, get_order(size), cpu_addr)) @@ -333,75 +392,11 @@ void dma_free_coherent(struct device *dev, size_t size, void *cpu_addr, dma_addr size = PAGE_ALIGN(size); - if (arch_is_coherent()) { - __dma_free_buffer(dma_to_page(dev, handle), size); - return; - } - - c = arm_vmregion_find_remove(&consistent_head, (unsigned long)cpu_addr); - if (!c) - goto no_area; - - 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); - 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); - - arm_vmregion_free(&consistent_head, c); + if (!arch_is_coherent()) + __dma_free_remap(cpu_addr, size); __dma_free_buffer(dma_to_page(dev, handle), size); - return; - - no_area: - printk(KERN_ERR "%s: trying to free invalid coherent area: %p\n", - __func__, cpu_addr); - dump_stack(); } -#else /* !CONFIG_MMU */ -void dma_free_coherent(struct device *dev, size_t size, void *cpu_addr, dma_addr_t handle) -{ - if (dma_release_from_coherent(dev, get_order(size), cpu_addr)) - return; - __dma_free_buffer(dma_to_page(dev, handle), PAGE_ALIGN(size)); -} -#endif /* CONFIG_MMU */ EXPORT_SYMBOL(dma_free_coherent); /* -- cgit v1.2.3-70-g09d2