From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5336DC43600 for ; Fri, 30 Apr 2021 05:57:41 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 033CD614A7 for ; Fri, 30 Apr 2021 05:57:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 033CD614A7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 97D9B8E0005; Fri, 30 Apr 2021 01:57:40 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 953EE8D0005; Fri, 30 Apr 2021 01:57:40 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 81DC08E0005; Fri, 30 Apr 2021 01:57:40 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0139.hostedemail.com [216.40.44.139]) by kanga.kvack.org (Postfix) with ESMTP id 68A6D8D0005 for ; Fri, 30 Apr 2021 01:57:40 -0400 (EDT) Received: from smtpin23.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 39B183649 for ; Fri, 30 Apr 2021 05:57:40 +0000 (UTC) X-FDA: 78087976680.23.CE2ACF3 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf29.hostedemail.com (Postfix) with ESMTP id 82A8BEF for ; Fri, 30 Apr 2021 05:57:35 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id E2E176147D; Fri, 30 Apr 2021 05:57:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1619762259; bh=5Bygb5VoHcpNiQHGyWIKOgr2vklJ9PR6sAE81j2BF5o=; h=Date:From:To:Subject:In-Reply-To:From; b=XUr5gdH+qDWvHwo/ha+H0VErCIowrWvFQPMpearTjDtsJzjAS57QtKe2vfbsWHJ6n Zl+9+dXgAXzOXXI9iJoj4joqBVfnLwHZs4Fr7vRYGEFezB8Xn6CmFDBZmbVZV13loe qauOdkckRr9xrJV+FWTiNFzVqSR0iN5gpdInOvGk= Date: Thu, 29 Apr 2021 22:57:38 -0700 From: Andrew Morton To: akpm@linux-foundation.org, chris@chris-wilson.co.uk, daniel.vetter@ffwll.ch, hch@lst.de, jani.nikula@linux.intel.com, joonas.lahtinen@linux.intel.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, peterz@infradead.org, rodrigo.vivi@intel.com, torvalds@linux-foundation.org Subject: [patch 087/178] i915: fix remap_io_sg to verify the pgprot Message-ID: <20210430055738.vRrQ3_yRK%akpm@linux-foundation.org> In-Reply-To: <20210429225251.02b6386d21b69255b4f6c163@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 82A8BEF Authentication-Results: imf29.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=XUr5gdH+; dmarc=none; spf=pass (imf29.hostedemail.com: domain of akpm@linux-foundation.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org X-Stat-Signature: 8sdq3uiq6tcmejyxgcbjqz3d19k5fe7y Received-SPF: none (linux-foundation.org>: No applicable sender policy available) receiver=imf29; identity=mailfrom; envelope-from=""; helo=mail.kernel.org; client-ip=198.145.29.99 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1619762255-765421 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Christoph Hellwig Subject: i915: fix remap_io_sg to verify the pgprot remap_io_sg claims that the pgprot is pre-verified using an io_mapping, but actually does not get passed an io_mapping and just uses the pgprot in the VMA. Remove the apply_to_page_range abuse and just loop over remap_pfn_range for each segment. Note: this could use io_mapping_map_user by passing an iomap to remap_io_sg if the maintainers can verify that the pgprot in the iomap in the only caller is indeed the desired one here. Link: https://lkml.kernel.org/r/20210326055505.1424432-5-hch@lst.de Signed-off-by: Christoph Hellwig Cc: Chris Wilson Cc: Daniel Vetter Cc: Jani Nikula Cc: Joonas Lahtinen Cc: Peter Zijlstra Cc: Rodrigo Vivi Signed-off-by: Andrew Morton --- drivers/gpu/drm/i915/i915_mm.c | 73 +++++++++---------------------- 1 file changed, 23 insertions(+), 50 deletions(-) --- a/drivers/gpu/drm/i915/i915_mm.c~i915-fix-remap_io_sg-to-verify-the-pgprot +++ a/drivers/gpu/drm/i915/i915_mm.c @@ -28,46 +28,10 @@ #include "i915_drv.h" -struct remap_pfn { - struct mm_struct *mm; - unsigned long pfn; - pgprot_t prot; - - struct sgt_iter sgt; - resource_size_t iobase; -}; +#define EXPECTED_FLAGS (VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP) #define use_dma(io) ((io) != -1) -static inline unsigned long sgt_pfn(const struct remap_pfn *r) -{ - if (use_dma(r->iobase)) - return (r->sgt.dma + r->sgt.curr + r->iobase) >> PAGE_SHIFT; - else - return r->sgt.pfn + (r->sgt.curr >> PAGE_SHIFT); -} - -static int remap_sg(pte_t *pte, unsigned long addr, void *data) -{ - struct remap_pfn *r = data; - - if (GEM_WARN_ON(!r->sgt.sgp)) - return -EINVAL; - - /* Special PTE are not associated with any struct page */ - set_pte_at(r->mm, addr, pte, - pte_mkspecial(pfn_pte(sgt_pfn(r), r->prot))); - r->pfn++; /* track insertions in case we need to unwind later */ - - r->sgt.curr += PAGE_SIZE; - if (r->sgt.curr >= r->sgt.max) - r->sgt = __sgt_iter(__sg_next(r->sgt.sgp), use_dma(r->iobase)); - - return 0; -} - -#define EXPECTED_FLAGS (VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP) - /** * remap_io_sg - remap an IO mapping to userspace * @vma: user vma to map to @@ -82,12 +46,7 @@ int remap_io_sg(struct vm_area_struct *v unsigned long addr, unsigned long size, struct scatterlist *sgl, resource_size_t iobase) { - struct remap_pfn r = { - .mm = vma->vm_mm, - .prot = vma->vm_page_prot, - .sgt = __sgt_iter(sgl, use_dma(iobase)), - .iobase = iobase, - }; + unsigned long pfn, len, remapped = 0; int err; /* We rely on prevalidation of the io-mapping to skip track_pfn(). */ @@ -96,11 +55,25 @@ int remap_io_sg(struct vm_area_struct *v if (!use_dma(iobase)) flush_cache_range(vma, addr, size); - err = apply_to_page_range(r.mm, addr, size, remap_sg, &r); - if (unlikely(err)) { - zap_vma_ptes(vma, addr, r.pfn << PAGE_SHIFT); - return err; - } - - return 0; + do { + if (use_dma(iobase)) { + if (!sg_dma_len(sgl)) + break; + pfn = (sg_dma_address(sgl) + iobase) >> PAGE_SHIFT; + len = sg_dma_len(sgl); + } else { + pfn = page_to_pfn(sg_page(sgl)); + len = sgl->length; + } + + err = remap_pfn_range(vma, addr + remapped, pfn, len, + vma->vm_page_prot); + if (err) + break; + remapped += len; + } while ((sgl = __sg_next(sgl))); + + if (err) + zap_vma_ptes(vma, addr, remapped); + return err; } _