From patchwork Wed May 10 08:55:25 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ruihan Li X-Patchwork-Id: 681146 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A61BBC7EE22 for ; Wed, 10 May 2023 09:04:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236942AbjEJJER (ORCPT ); Wed, 10 May 2023 05:04:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55942 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236932AbjEJJEM (ORCPT ); Wed, 10 May 2023 05:04:12 -0400 X-Greylist: delayed 477 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Wed, 10 May 2023 02:03:54 PDT Received: from pku.edu.cn (mx18.pku.edu.cn [162.105.129.181]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id B636CE4A; Wed, 10 May 2023 02:03:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pku.edu.cn; s=dkim; h=Received:From:To:Cc:Subject:Date: Message-Id:In-Reply-To:References:MIME-Version: Content-Transfer-Encoding; bh=uc/joagnVnWX0pVL8sA/swhhcGx1a7P3dQ TDyW7FP10=; b=ZmFL1Miz+iwxUAejxmnXZrzMvhWRO2gTDNymFiYKOFmOJx2Phg n86fSt1XcCM1orEYX0LJ8T7Z57qLiHA5O81og7eaOHCblqDcOVLLfy3XPdMK7Mvo aKEwhnHrpWzNksDyzH7/HBiexN+Atn1CCGgm+sIUKlxloB2ZQEE2gI3E8= Received: from localhost.localdomain (unknown [10.7.101.92]) by front01 (Coremail) with SMTP id 5oFpogBnb2cIXFtkW9d5Ag--.63159S4; Wed, 10 May 2023 16:55:42 +0800 (CST) From: Ruihan Li To: linux-mm@kvack.org Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Pasha Tatashin , David Hildenbrand , Matthew Wilcox , Andrew Morton , Christoph Hellwig , Greg Kroah-Hartman , Ruihan Li , stable@vger.kernel.org Subject: [PATCH 2/4] usb: usbfs: Use consistent mmap functions Date: Wed, 10 May 2023 16:55:25 +0800 Message-Id: <20230510085527.57953-3-lrh2000@pku.edu.cn> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230510085527.57953-1-lrh2000@pku.edu.cn> References: <20230510085527.57953-1-lrh2000@pku.edu.cn> MIME-Version: 1.0 X-CM-TRANSID: 5oFpogBnb2cIXFtkW9d5Ag--.63159S4 X-Coremail-Antispam: 1UD129KBjvJXoW7Kw45ZF1kZrWfCw4UCr17KFg_yoW8KFWDpF W8K3yj9F40qFySvr1q9an5WFn5G3s5KFyUWrW2v3sxu3W3Jr1SkFWFya4YqF17tr18Xrna qFWqyw13C3W5uFDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBF1xkIjI8I6I8E6xAIw20EY4v20xvaj40_Wr0E3s1l1IIY67AE w4v_Jr0_Jr4l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xvwVC0I7IYx2 IY67AKxVWDJVCq3wA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxVW0oVCq3wA2z4x0Y4vEx4A2 jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq3wAac4AC62xK8xCEY4 vEwIxC4wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv 7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r 1j6r4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02 628vn2kIc2xKxwCY02Avz4vE-syl42xK82IYc2Ij64vIr41l42xK82IY6x8ErcxFaVAv8V WkJr1UJwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E 7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcV C0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF 04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7 CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUQZ23UUUUU= X-CM-SenderInfo: yssqiiarrvmko6sn3hxhgxhubq/1tbiAgEEBVPy770DbwAZsE Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org When hcd->localmem_pool is non-null, it is used to allocate DMA memory. In this case, the dma address will be properly returned (in dma_handle), and dma_mmap_coherent should be used to map this memory into the user space. However, the current implementation uses pfn_remap_range, which is supposed to map normal pages (instead of DMA pages). Instead of repeating the logic in the memory allocation function, this patch introduces a more robust solution. To address the previous issue, this patch checks the type of allocated memory by testing whether dma_handle is properly set. If dma_handle is properly returned, it means some DMA pages are allocated and dma_mmap_coherent should be used to map them. Otherwise, normal pages are allocated and pfn_remap_range should be called. This ensures that the correct mmap functions are used consistently, independently with logic details that determine which type of memory gets allocated. Fixes: a0e710a7def4 ("USB: usbfs: fix mmap dma mismatch") Cc: stable@vger.kernel.org Signed-off-by: Ruihan Li --- drivers/usb/core/devio.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c index b4cf9e860..5067030b7 100644 --- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -235,7 +235,7 @@ static int usbdev_mmap(struct file *file, struct vm_area_struct *vma) size_t size = vma->vm_end - vma->vm_start; void *mem; unsigned long flags; - dma_addr_t dma_handle; + dma_addr_t dma_handle = DMA_MAPPING_ERROR; int ret; ret = usbfs_increase_memory_usage(size + sizeof(struct usb_memory)); @@ -265,7 +265,13 @@ static int usbdev_mmap(struct file *file, struct vm_area_struct *vma) usbm->vma_use_count = 1; INIT_LIST_HEAD(&usbm->memlist); - if (hcd->localmem_pool || !hcd_uses_dma(hcd)) { + /* In DMA-unavailable cases, hcd_buffer_alloc_pages allocates + * normal pages and assigns DMA_MAPPING_ERROR to dma_handle. Check + * whether we are in such cases, and then use remap_pfn_range (or + * dma_mmap_coherent) to map normal (or DMA) pages into the user + * space, respectively. + */ + if (dma_handle == DMA_MAPPING_ERROR) { if (remap_pfn_range(vma, vma->vm_start, virt_to_phys(usbm->mem) >> PAGE_SHIFT, size, vma->vm_page_prot) < 0) {