From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lgeamrelo04.lge.com (lgeamrelo04.lge.com [156.147.1.127]) by lists.ozlabs.org (Postfix) with ESMTP id 2E5CA1A0055 for ; Tue, 3 Jun 2014 11:08:45 +1000 (EST) From: Joonsoo Kim To: Andrew Morton , "Aneesh Kumar K.V" , Marek Szyprowski , Michal Nazarewicz Subject: [RFC PATCH 2/3] DMA, CMA: use general CMA reserved area management framework Date: Tue, 3 Jun 2014 10:11:57 +0900 Message-Id: <1401757919-30018-3-git-send-email-iamjoonsoo.kim@lge.com> In-Reply-To: <1401757919-30018-1-git-send-email-iamjoonsoo.kim@lge.com> References: <1401757919-30018-1-git-send-email-iamjoonsoo.kim@lge.com> Cc: Russell King - ARM Linux , kvm@vger.kernel.org, linux-mm@kvack.org, Gleb Natapov , Greg Kroah-Hartman , Alexander Graf , kvm-ppc@vger.kernel.org, linux-kernel@vger.kernel.org, Minchan Kim , Paul Mackerras , Paolo Bonzini , Joonsoo Kim , linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Now, we have general CMA reserved area management framework, so use it for future maintainabilty. There is no functional change. Signed-off-by: Joonsoo Kim diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig index b3fe1cc..4eac559 100644 --- a/drivers/base/Kconfig +++ b/drivers/base/Kconfig @@ -283,16 +283,6 @@ config CMA_ALIGNMENT If unsure, leave the default value "8". -config DMA_CMA_AREAS - int "Maximum count of the CMA device-private areas" - default 7 - help - CMA allows to create CMA areas for particular devices. This parameter - sets the maximum number of such device private CMA areas in the - system. - - If unsure, leave the default value "7". - endif endmenu diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c index 48cdac8..4bce4e1 100644 --- a/drivers/base/dma-contiguous.c +++ b/drivers/base/dma-contiguous.c @@ -24,23 +24,9 @@ #include #include -#include -#include -#include #include -#include -#include -#include #include - -struct cma { - unsigned long base_pfn; - unsigned long count; - unsigned long *bitmap; - struct mutex lock; -}; - -struct cma *dma_contiguous_default_area; +#include #ifdef CONFIG_CMA_SIZE_MBYTES #define CMA_SIZE_MBYTES CONFIG_CMA_SIZE_MBYTES @@ -48,6 +34,8 @@ struct cma *dma_contiguous_default_area; #define CMA_SIZE_MBYTES 0 #endif +struct cma *dma_contiguous_default_area; + /* * Default global CMA area size can be defined in kernel's .config. * This is useful mainly for distro maintainers to create a kernel @@ -154,55 +142,6 @@ void __init dma_contiguous_reserve(phys_addr_t limit) } } -static DEFINE_MUTEX(cma_mutex); - -static int __init cma_activate_area(struct cma *cma) -{ - int bitmap_size = BITS_TO_LONGS(cma->count) * sizeof(long); - unsigned long base_pfn = cma->base_pfn, pfn = base_pfn; - unsigned i = cma->count >> pageblock_order; - struct zone *zone; - - cma->bitmap = kzalloc(bitmap_size, GFP_KERNEL); - - if (!cma->bitmap) - return -ENOMEM; - - WARN_ON_ONCE(!pfn_valid(pfn)); - zone = page_zone(pfn_to_page(pfn)); - - do { - unsigned j; - base_pfn = pfn; - for (j = pageblock_nr_pages; j; --j, pfn++) { - WARN_ON_ONCE(!pfn_valid(pfn)); - if (page_zone(pfn_to_page(pfn)) != zone) - return -EINVAL; - } - init_cma_reserved_pageblock(pfn_to_page(base_pfn)); - } while (--i); - - mutex_init(&cma->lock); - return 0; -} - -static struct cma cma_areas[MAX_DMA_CMA_AREAS]; -static unsigned cma_area_count; - -static int __init cma_init_reserved_areas(void) -{ - int i; - - for (i = 0; i < cma_area_count; i++) { - int ret = cma_activate_area(&cma_areas[i]); - if (ret) - return ret; - } - - return 0; -} -core_initcall(cma_init_reserved_areas); - /** * dma_contiguous_reserve_area() - reserve custom contiguous area * @size: Size of the reserved area (in bytes), @@ -224,176 +163,31 @@ int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, phys_addr_t limit, struct cma **res_cma, bool fixed) { - struct cma *cma = &cma_areas[cma_area_count]; - phys_addr_t alignment; - int ret = 0; - - pr_debug("%s(size %lx, base %08lx, limit %08lx)\n", __func__, - (unsigned long)size, (unsigned long)base, - (unsigned long)limit); - - /* Sanity checks */ - if (cma_area_count == ARRAY_SIZE(cma_areas)) { - pr_err("Not enough slots for CMA reserved regions!\n"); - return -ENOSPC; - } - - if (!size) - return -EINVAL; - - /* Sanitise input arguments */ - alignment = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order); - base = ALIGN(base, alignment); - size = ALIGN(size, alignment); - limit &= ~(alignment - 1); - - /* Reserve memory */ - if (base && fixed) { - if (memblock_is_region_reserved(base, size) || - memblock_reserve(base, size) < 0) { - ret = -EBUSY; - goto err; - } - } else { - phys_addr_t addr = memblock_alloc_range(size, alignment, base, - limit); - if (!addr) { - ret = -ENOMEM; - goto err; - } else { - base = addr; - } - } - - /* - * Each reserved area must be initialised later, when more kernel - * subsystems (like slab allocator) are available. - */ - cma->base_pfn = PFN_DOWN(base); - cma->count = size >> PAGE_SHIFT; - *res_cma = cma; - cma_area_count++; + int ret; + struct cma *cma; - pr_info("CMA: reserved %ld MiB at %08lx\n", (unsigned long)size / SZ_1M, - (unsigned long)base); + ret = cma_declare_contiguous(size, base, limit, 0, 0, fixed, &cma); + if (ret) + return ret; /* Architecture specific contiguous memory fixup. */ dma_contiguous_early_fixup(base, size); - return 0; -err: - pr_err("CMA: failed to reserve %ld MiB\n", (unsigned long)size / SZ_1M); - return ret; -} + *res_cma = cma; -static void clear_cma_bitmap(struct cma *cma, unsigned long pfn, int count) -{ - mutex_lock(&cma->lock); - bitmap_clear(cma->bitmap, pfn - cma->base_pfn, count); - mutex_unlock(&cma->lock); + return 0; } -/** - * dma_alloc_from_contiguous() - allocate pages from contiguous area - * @dev: Pointer to device for which the allocation is performed. - * @count: Requested number of pages. - * @align: Requested alignment of pages (in PAGE_SIZE order). - * - * This function allocates memory buffer for specified device. It uses - * device specific contiguous memory area if available or the default - * global one. Requires architecture specific dev_get_cma_area() helper - * function. - */ struct page *dma_alloc_from_contiguous(struct device *dev, int count, unsigned int align) { - unsigned long mask, pfn, pageno, start = 0; - struct cma *cma = dev_get_cma_area(dev); - struct page *page = NULL; - int ret; - - if (!cma || !cma->count) - return NULL; - if (align > CONFIG_CMA_ALIGNMENT) align = CONFIG_CMA_ALIGNMENT; - pr_debug("%s(cma %p, count %d, align %d)\n", __func__, (void *)cma, - count, align); - - if (!count) - return NULL; - - mask = (1 << align) - 1; - - - for (;;) { - mutex_lock(&cma->lock); - pageno = bitmap_find_next_zero_area(cma->bitmap, cma->count, - start, count, mask); - if (pageno >= cma->count) { - mutex_unlock(&cma->lock); - break; - } - bitmap_set(cma->bitmap, pageno, count); - /* - * It's safe to drop the lock here. We've marked this region for - * our exclusive use. If the migration fails we will take the - * lock again and unmark it. - */ - mutex_unlock(&cma->lock); - - pfn = cma->base_pfn + pageno; - mutex_lock(&cma_mutex); - ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA); - mutex_unlock(&cma_mutex); - if (ret == 0) { - page = pfn_to_page(pfn); - break; - } else if (ret != -EBUSY) { - clear_cma_bitmap(cma, pfn, count); - break; - } - clear_cma_bitmap(cma, pfn, count); - pr_debug("%s(): memory range at %p is busy, retrying\n", - __func__, pfn_to_page(pfn)); - /* try again with a bit different memory target */ - start = pageno + mask + 1; - } - - pr_debug("%s(): returned %p\n", __func__, page); - return page; + return cma_alloc(dev_get_cma_area(dev), count, align); } -/** - * dma_release_from_contiguous() - release allocated pages - * @dev: Pointer to device for which the pages were allocated. - * @pages: Allocated pages. - * @count: Number of allocated pages. - * - * This function releases memory allocated by dma_alloc_from_contiguous(). - * It returns false when provided pages do not belong to contiguous area and - * true otherwise. - */ bool dma_release_from_contiguous(struct device *dev, struct page *pages, int count) { - struct cma *cma = dev_get_cma_area(dev); - unsigned long pfn; - - if (!cma || !pages) - return false; - - pr_debug("%s(page %p)\n", __func__, (void *)pages); - - pfn = page_to_pfn(pages); - - if (pfn < cma->base_pfn || pfn >= cma->base_pfn + cma->count) - return false; - - VM_BUG_ON(pfn + count > cma->base_pfn + cma->count); - - free_contig_range(pfn, count); - clear_cma_bitmap(cma, pfn, count); - - return true; + return cma_release(dev_get_cma_area(dev), pages, count); } diff --git a/include/linux/dma-contiguous.h b/include/linux/dma-contiguous.h index dfb1dc9..ecb85ac 100644 --- a/include/linux/dma-contiguous.h +++ b/include/linux/dma-contiguous.h @@ -53,9 +53,10 @@ #ifdef __KERNEL__ +#include + struct cma; struct page; -struct device; #ifdef CONFIG_DMA_CMA -- 1.7.9.5