From patchwork Mon Apr 22 17:59:30 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 10911335 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 24A1A1708 for ; Mon, 22 Apr 2019 18:03:17 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 167AA28786 for ; Mon, 22 Apr 2019 18:03:17 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0ABDC28789; Mon, 22 Apr 2019 18:03:17 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 8E7A928786 for ; Mon, 22 Apr 2019 18:03:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=8OAbjaFr/Nba/+hDgXHPb11BWcDMnBN2m+1lUSzztQA=; b=BfoTch9E1L9Axr xP4vrE4QyTlycFMaWW9U3tM2fjDSc3Wr+bJll+IKOfYCEm2vtgvx/EfjE9WuCZc9hpZ5c++hxcEBp PxFDyC+3OKDH+giyQI7a6F+cI7XoWRXMDYi2QO6xrNS4vdI5SzLgkvgnpoATtQOXsFiVFB6J5Qlc+ +4lyfPh3u2WbfBimC3ATlyWGmo0OmsvYcc6zbJHkffvK/NTE4pdJA2DH5Q8UYgK76OAec2o7SGcQY Z+fpgVMQJAUO+eGgnCD5RLs9Csx27kAT3SMBrjlyrvJRcs/gaWhiWUR+qYZJQs6yCBKPAJWNLSmew CDQsNaPirweflwo+CC9Q==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hIdHc-0004zo-A8; Mon, 22 Apr 2019 18:03:12 +0000 Received: from 213-225-37-80.nat.highway.a1.net ([213.225.37.80] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1hIdFF-00027M-3t; Mon, 22 Apr 2019 18:00:45 +0000 From: Christoph Hellwig To: Robin Murphy Subject: [PATCH 14/26] iommu/dma: Refactor iommu_dma_free Date: Mon, 22 Apr 2019 19:59:30 +0200 Message-Id: <20190422175942.18788-15-hch@lst.de> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190422175942.18788-1-hch@lst.de> References: <20190422175942.18788-1-hch@lst.de> MIME-Version: 1.0 X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Tom Lendacky , Catalin Marinas , Joerg Roedel , Will Deacon , linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Robin Murphy The freeing logic was made particularly horrible by part of it being opaque to the arch wrapper, which led to a lot of convoluted repetition to ensure each path did everything in the right order. Now that it's all private, we can pick apart and consolidate the logically-distinct steps of freeing the IOMMU mapping, the underlying pages, and the CPU remap (if necessary) into something much more manageable. Signed-off-by: Robin Murphy [various cosmetic changes to the code flow] Signed-off-by: Christoph Hellwig --- drivers/iommu/dma-iommu.c | 75 ++++++++++++++++++--------------------- 1 file changed, 35 insertions(+), 40 deletions(-) diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 4632b9d301a1..9658c4cc3cfe 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -916,6 +916,41 @@ static void iommu_dma_unmap_resource(struct device *dev, dma_addr_t handle, __iommu_dma_unmap(dev, handle, size); } +static void iommu_dma_free(struct device *dev, size_t size, void *cpu_addr, + dma_addr_t handle, unsigned long attrs) +{ + size_t alloc_size = PAGE_ALIGN(size); + int count = alloc_size >> PAGE_SHIFT; + struct page *page = NULL; + + __iommu_dma_unmap(dev, handle, size); + + /* Non-coherent atomic allocation? Easy */ + if (dma_free_from_pool(cpu_addr, alloc_size)) + return; + + if (is_vmalloc_addr(cpu_addr)) { + /* + * If it the address is remapped, then it's either non-coherent + * or highmem CMA, or an iommu_dma_alloc_remap() construction. + */ + struct page **pages = __iommu_dma_get_pages(cpu_addr); + + if (pages) + __iommu_dma_free_pages(pages, count); + else + page = vmalloc_to_page(cpu_addr); + + dma_common_free_remap(cpu_addr, alloc_size, VM_USERMAP); + } else { + /* Lowmem means a coherent atomic or CMA allocation */ + page = virt_to_page(cpu_addr); + } + + if (page && !dma_release_from_contiguous(dev, page, count)) + __free_pages(page, get_order(alloc_size)); +} + static void *iommu_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp, unsigned long attrs) { @@ -985,46 +1020,6 @@ static void *iommu_dma_alloc(struct device *dev, size_t size, return addr; } -static void iommu_dma_free(struct device *dev, size_t size, void *cpu_addr, - dma_addr_t handle, unsigned long attrs) -{ - size_t iosize = size; - - size = PAGE_ALIGN(size); - /* - * @cpu_addr will be one of 4 things depending on how it was allocated: - * - A remapped array of pages for contiguous allocations. - * - A remapped array of pages from iommu_dma_alloc_remap(), for all - * non-atomic allocations. - * - A non-cacheable alias from the atomic pool, for atomic - * allocations by non-coherent devices. - * - A normal lowmem address, for atomic allocations by - * coherent devices. - * Hence how dodgy the below logic looks... - */ - if (dma_in_atomic_pool(cpu_addr, size)) { - __iommu_dma_unmap(dev, handle, iosize); - dma_free_from_pool(cpu_addr, size); - } else if (attrs & DMA_ATTR_FORCE_CONTIGUOUS) { - struct page *page = vmalloc_to_page(cpu_addr); - - __iommu_dma_unmap(dev, handle, iosize); - dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT); - dma_common_free_remap(cpu_addr, size, VM_USERMAP); - } else if (is_vmalloc_addr(cpu_addr)){ - struct page **pages = __iommu_dma_get_pages(cpu_addr); - - if (WARN_ON(!pages)) - return; - __iommu_dma_unmap(dev, handle, iosize); - __iommu_dma_free_pages(pages, size >> PAGE_SHIFT); - dma_common_free_remap(cpu_addr, size, VM_USERMAP); - } else { - __iommu_dma_unmap(dev, handle, iosize); - __free_pages(virt_to_page(cpu_addr), get_order(size)); - } -} - static int __iommu_dma_mmap_pfn(struct vm_area_struct *vma, unsigned long pfn, size_t size) {