From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: [patch 093/128] dma-mapping: use vmap insted of reimplementing it Date: Mon, 01 Jun 2020 21:50:32 -0700 Message-ID: <20200602045032.FXJXMNN2f%akpm@linux-foundation.org> References: <20200601214457.919c35648e96a2b46b573fe1@linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.29.99]:42414 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725793AbgFBEuf (ORCPT ); Tue, 2 Jun 2020 00:50:35 -0400 In-Reply-To: <20200601214457.919c35648e96a2b46b573fe1@linux-foundation.org> Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: airlied@linux.ie, akpm@linux-foundation.org, benh@kernel.crashing.org, borntraeger@de.ibm.com, catalin.marinas@arm.com, christophe.leroy@c-s.fr, daniel.vetter@ffwll.ch, daniel@ffwll.ch, gor@linux.ibm.com, gregkh@linuxfoundation.org, haiyangz@microsoft.com, hannes@cmpxchg.org, hch@lst.de, heiko.carstens@de.ibm.com, kys@microsoft.com, labbott@redhat.com, linux-mm@kvack.org, mark.rutland@arm.com, mikelley@microsoft.com, minchan@kernel.org, mm-commits@vger.kernel.org, ngupta@vflare.org, paulus@ozlabs.org, peterz@infradead.org, robin.murphy@arm.com, sakari.ailus@linux.intel.com, sthemmin@microsoft.com, sumit.semwal@linaro.org, torvalds@linux-foundation.org, wei.liu@kernel.org, will@kernel.org, xiang@kernel.org From: Christoph Hellwig Subject: dma-mapping: use vmap insted of reimplementing it Replace the open coded instance of vmap with the actual function. In the non-contiguous (IOMMU) case this requires an extra find_vm_area, but given that this isn't a fast path function that is a small price to pay. Link: http://lkml.kernel.org/r/20200414131348.444715-6-hch@lst.de Signed-off-by: Christoph Hellwig Acked-by: Peter Zijlstra (Intel) Cc: Christian Borntraeger Cc: Christophe Leroy Cc: Daniel Vetter Cc: Daniel Vetter Cc: David Airlie Cc: Gao Xiang Cc: Greg Kroah-Hartman Cc: Haiyang Zhang Cc: Johannes Weiner Cc: "K. Y. Srinivasan" Cc: Laura Abbott Cc: Mark Rutland Cc: Michael Kelley Cc: Minchan Kim Cc: Nitin Gupta Cc: Robin Murphy Cc: Sakari Ailus Cc: Stephen Hemminger Cc: Sumit Semwal Cc: Wei Liu Cc: Benjamin Herrenschmidt Cc: Catalin Marinas Cc: Heiko Carstens Cc: Paul Mackerras Cc: Vasily Gorbik Cc: Will Deacon Signed-off-by: Andrew Morton --- kernel/dma/remap.c | 48 ++++++++++--------------------------------- 1 file changed, 12 insertions(+), 36 deletions(-) --- a/kernel/dma/remap.c~dma-mapping-use-vmap-insted-of-reimplementing-it +++ a/kernel/dma/remap.c @@ -20,23 +20,6 @@ struct page **dma_common_find_pages(void return area->pages; } -static struct vm_struct *__dma_common_pages_remap(struct page **pages, - size_t size, pgprot_t prot, const void *caller) -{ - struct vm_struct *area; - - area = get_vm_area_caller(size, VM_DMA_COHERENT, caller); - if (!area) - return NULL; - - if (map_vm_area(area, prot, pages)) { - vunmap(area->addr); - return NULL; - } - - return area; -} - /* * Remaps an array of PAGE_SIZE pages into another vm_area. * Cannot be used in non-sleeping contexts @@ -44,15 +27,12 @@ static struct vm_struct *__dma_common_pa void *dma_common_pages_remap(struct page **pages, size_t size, pgprot_t prot, const void *caller) { - struct vm_struct *area; + void *vaddr; - area = __dma_common_pages_remap(pages, size, prot, caller); - if (!area) - return NULL; - - area->pages = pages; - - return area->addr; + vaddr = vmap(pages, size >> PAGE_SHIFT, VM_DMA_COHERENT, prot); + if (vaddr) + find_vm_area(vaddr)->pages = pages; + return vaddr; } /* @@ -62,24 +42,20 @@ void *dma_common_pages_remap(struct page void *dma_common_contiguous_remap(struct page *page, size_t size, pgprot_t prot, const void *caller) { - int i; + int count = size >> PAGE_SHIFT; struct page **pages; - struct vm_struct *area; + void *vaddr; + int i; - pages = kmalloc(sizeof(struct page *) << get_order(size), GFP_KERNEL); + pages = kmalloc_array(count, sizeof(struct page *), GFP_KERNEL); if (!pages) return NULL; - - for (i = 0; i < (size >> PAGE_SHIFT); i++) + for (i = 0; i < count; i++) pages[i] = nth_page(page, i); - - area = __dma_common_pages_remap(pages, size, prot, caller);