From 33f00dcedb0e22cdb156a23632814fc580fcfcf8 Mon Sep 17 00:00:00 2001 From: Ilya Yanok Date: Thu, 12 Feb 2009 13:20:53 +0000 Subject: [PATCH] powerpc: Rework dma-noncoherent to use generic vmalloc layer This patch rewrites consistent dma allocations support to use vmalloc layer to allocate virtual memory space from vmalloc pool and get rid of CONFIG_CONSISTENT_{START,SIZE}. This greatly simplifies the code by effectively removing a custom allocator we had for virtual space. Signed-off-by: Ilya Yanok Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/Kconfig | 25 --- arch/powerpc/lib/dma-noncoherent.c | 303 ++++++----------------------- 2 files changed, 57 insertions(+), 271 deletions(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index e46995a21685..d11896b445b6 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -833,31 +833,6 @@ config TASK_SIZE default "0x80000000" if PPC_PREP || PPC_8xx default "0xc0000000" -config CONSISTENT_START_BOOL - bool "Set custom consistent memory pool address" - depends on ADVANCED_OPTIONS && NOT_COHERENT_CACHE - help - This option allows you to set the base virtual address - of the consistent memory pool. This pool of virtual - memory is used to make consistent memory allocations. - -config CONSISTENT_START - hex "Base virtual address of consistent memory pool" if CONSISTENT_START_BOOL - default "0xfd000000" if (NOT_COHERENT_CACHE && 8xx) - default "0xff100000" if NOT_COHERENT_CACHE - -config CONSISTENT_SIZE_BOOL - bool "Set custom consistent memory pool size" - depends on ADVANCED_OPTIONS && NOT_COHERENT_CACHE - help - This option allows you to set the size of the - consistent memory pool. This pool of virtual memory - is used to make consistent memory allocations. - -config CONSISTENT_SIZE - hex "Size of consistent memory pool" if CONSISTENT_SIZE_BOOL - default "0x00200000" if NOT_COHERENT_CACHE - config PIN_TLB bool "Pinned Kernel TLBs (860 ONLY)" depends on ADVANCED_OPTIONS && 8xx diff --git a/arch/powerpc/lib/dma-noncoherent.c b/arch/powerpc/lib/dma-noncoherent.c index b7dc4c19f582..005a28d380af 100644 --- a/arch/powerpc/lib/dma-noncoherent.c +++ b/arch/powerpc/lib/dma-noncoherent.c @@ -29,120 +29,10 @@ #include #include #include +#include #include -/* - * This address range defaults to a value that is safe for all - * platforms which currently set CONFIG_NOT_COHERENT_CACHE. It - * can be further configured for specific applications under - * the "Advanced Setup" menu. -Matt - */ -#define CONSISTENT_BASE (CONFIG_CONSISTENT_START) -#define CONSISTENT_END (CONFIG_CONSISTENT_START + CONFIG_CONSISTENT_SIZE) -#define CONSISTENT_OFFSET(x) (((unsigned long)(x) - CONSISTENT_BASE) >> PAGE_SHIFT) - -/* - * This is the page table (2MB) covering uncached, DMA consistent allocations - */ -static pte_t *consistent_pte; -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 ppc_vm_region { - struct list_head vm_list; - unsigned long vm_start; - unsigned long vm_end; -}; - -static struct ppc_vm_region consistent_head = { - .vm_list = LIST_HEAD_INIT(consistent_head.vm_list), - .vm_start = CONSISTENT_BASE, - .vm_end = CONSISTENT_END, -}; - -static struct ppc_vm_region * -ppc_vm_region_alloc(struct ppc_vm_region *head, size_t size, gfp_t gfp) -{ - unsigned long addr = head->vm_start, end = head->vm_end - size; - unsigned long flags; - struct ppc_vm_region *c, *new; - - new = kmalloc(sizeof(struct ppc_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; - - spin_unlock_irqrestore(&consistent_lock, flags); - return new; - - nospc: - spin_unlock_irqrestore(&consistent_lock, flags); - kfree(new); - out: - return NULL; -} - -static struct ppc_vm_region *ppc_vm_region_find(struct ppc_vm_region *head, unsigned long addr) -{ - struct ppc_vm_region *c; - - list_for_each_entry(c, &head->vm_list, vm_list) { - if (c->vm_start == addr) - goto out; - } - c = NULL; - out: - return c; -} - /* * Allocate DMA-coherent memory space and return both the kernel remapped * virtual and bus address for that space. @@ -151,21 +41,21 @@ void * __dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp) { struct page *page; - struct ppc_vm_region *c; unsigned long order; + int i; + unsigned int nr_pages = PAGE_ALIGN(size)>>PAGE_SHIFT; + unsigned int array_size = nr_pages * sizeof(struct page *); + struct page **pages; + struct page *end; u64 mask = 0x00ffffff, limit; /* ISA default */ + struct vm_struct *area; - if (!consistent_pte) { - printk(KERN_ERR "%s: not initialised\n", __func__); - dump_stack(); - return NULL; - } - + BUG_ON(!mem_init_done); 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 %#Lx)\n", - size, mask); + if (limit && size >= limit) { + printk(KERN_WARNING "coherent allocation too big (requested " + "%#x mask %#Lx)\n", size, mask); return NULL; } @@ -178,6 +68,8 @@ __dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp) if (!page) goto no_page; + end = page + (1 << order); + /* * Invalidate any data that might be lurking in the * kernel direct-mapped region for device DMA. @@ -188,48 +80,59 @@ __dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp) flush_dcache_range(kaddr, kaddr + size); } + split_page(page, order); + /* - * Allocate a virtual address in the consistent mapping region. + * Set the "dma handle" */ - c = ppc_vm_region_alloc(&consistent_head, size, - gfp & ~(__GFP_DMA | __GFP_HIGHMEM)); - if (c) { - unsigned long vaddr = c->vm_start; - pte_t *pte = consistent_pte + CONSISTENT_OFFSET(vaddr); - struct page *end = page + (1 << order); - - split_page(page, order); - - /* - * Set the "dma handle" - */ - *handle = page_to_phys(page); + *handle = page_to_phys(page); + + area = get_vm_area_caller(size, VM_IOREMAP, + __builtin_return_address(1)); + if (!area) + goto out_free_pages; + + if (array_size > PAGE_SIZE) { + pages = vmalloc(array_size); + area->flags |= VM_VPAGES; + } else { + pages = kmalloc(array_size, GFP_KERNEL); + } + if (!pages) + goto out_free_area; - do { - BUG_ON(!pte_none(*pte)); + area->pages = pages; + area->nr_pages = nr_pages; - SetPageReserved(page); - set_pte_at(&init_mm, vaddr, - pte, mk_pte(page, pgprot_noncached(PAGE_KERNEL))); - page++; - pte++; - vaddr += PAGE_SIZE; - } while (size -= PAGE_SIZE); + for (i = 0; i < nr_pages; i++) + pages[i] = page + i; - /* - * Free the otherwise unused pages. - */ - while (page < end) { - __free_page(page); - page++; - } + if (map_vm_area(area, pgprot_noncached(PAGE_KERNEL), &pages)) + goto out_unmap; - return (void *)c->vm_start; + /* + * Free the otherwise unused pages. + */ + page += nr_pages; + while (page < end) { + __free_page(page); + page++; } + return area->addr; +out_unmap: + vunmap(area->addr); + if (array_size > PAGE_SIZE) + vfree(pages); + else + kfree(pages); + goto out_free_pages; +out_free_area: + free_vm_area(area); +out_free_pages: if (page) __free_pages(page, order); - no_page: +no_page: return NULL; } EXPORT_SYMBOL(__dma_alloc_coherent); @@ -239,103 +142,11 @@ EXPORT_SYMBOL(__dma_alloc_coherent); */ void __dma_free_coherent(size_t size, void *vaddr) { - struct ppc_vm_region *c; - unsigned long flags, addr; - pte_t *ptep; - - size = PAGE_ALIGN(size); - - spin_lock_irqsave(&consistent_lock, flags); - - c = ppc_vm_region_find(&consistent_head, (unsigned long)vaddr); - 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; - } - - ptep = consistent_pte + CONSISTENT_OFFSET(c->vm_start); - addr = c->vm_start; - do { - pte_t pte = ptep_get_and_clear(&init_mm, addr, ptep); - unsigned long pfn; - - ptep++; - addr += PAGE_SIZE; + vfree(vaddr); - if (!pte_none(pte) && pte_present(pte)) { - pfn = pte_pfn(pte); - - if (pfn_valid(pfn)) { - struct page *page = pfn_to_page(pfn); - 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); - - 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__, vaddr); - dump_stack(); } EXPORT_SYMBOL(__dma_free_coherent); -/* - * Initialise the consistent memory allocation. - */ -static int __init dma_alloc_init(void) -{ - pgd_t *pgd; - pud_t *pud; - pmd_t *pmd; - pte_t *pte; - int ret = 0; - - do { - pgd = pgd_offset(&init_mm, CONSISTENT_BASE); - pud = pud_alloc(&init_mm, pgd, CONSISTENT_BASE); - pmd = pmd_alloc(&init_mm, pud, CONSISTENT_BASE); - if (!pmd) { - printk(KERN_ERR "%s: no pmd tables\n", __func__); - ret = -ENOMEM; - break; - } - - pte = pte_alloc_kernel(pmd, CONSISTENT_BASE); - if (!pte) { - printk(KERN_ERR "%s: no pte tables\n", __func__); - ret = -ENOMEM; - break; - } - - consistent_pte = pte; - } while (0); - - return ret; -} - -core_initcall(dma_alloc_init); - /* * make an area consistent. */ -- 2.20.1