From patchwork Mon Aug 24 18:36:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Hubbard X-Patchwork-Id: 11734007 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id F2B25175D for ; Mon, 24 Aug 2020 18:36:43 +0000 (UTC) Received: by mail.kernel.org (Postfix) id EE2892075B; Mon, 24 Aug 2020 18:36:43 +0000 (UTC) Delivered-To: soc@kernel.org Received: from hqnvemgate26.nvidia.com (hqnvemgate26.nvidia.com [216.228.121.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BA3832074D; Mon, 24 Aug 2020 18:36:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="iVS8/GaD" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BA3832074D Authentication-Results: mail.kernel.org; dmarc=pass (p=none dis=none) header.from=nvidia.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=jhubbard@nvidia.com Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqnvemgate26.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Mon, 24 Aug 2020 11:36:29 -0700 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Mon, 24 Aug 2020 11:36:43 -0700 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Mon, 24 Aug 2020 11:36:43 -0700 Received: from HQMAIL105.nvidia.com (172.20.187.12) by HQMAIL111.nvidia.com (172.20.187.18) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Mon, 24 Aug 2020 18:36:43 +0000 Received: from hqnvemgw03.nvidia.com (10.124.88.68) by HQMAIL105.nvidia.com (172.20.187.12) with Microsoft SMTP Server (TLS) id 15.0.1473.3 via Frontend Transport; Mon, 24 Aug 2020 18:36:43 +0000 Received: from sandstorm.nvidia.com (Not Verified[10.2.58.8]) by hqnvemgw03.nvidia.com with Trustwave SEG (v7,5,8,10121) id ; Mon, 24 Aug 2020 11:36:42 -0700 From: John Hubbard To: List-Id: CC: , , , , , , , Sumit Semwal , , , Subject: [PATCH v2] tee: convert convert get_user_pages() --> pin_user_pages() Date: Mon, 24 Aug 2020 11:36:41 -0700 Message-ID: <20200824183641.632126-1-jhubbard@nvidia.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: References: MIME-Version: 1.0 X-NVConfidentiality: public DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1598294189; bh=z82gApoeMO2LnErU5mpg0j+Kb/ttabmSFcmdgse888w=; h=X-PGP-Universal:From:To:CC:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:X-NVConfidentiality: Content-Transfer-Encoding:Content-Type; b=iVS8/GaDU9zmT9vo7ZZLTFMXFYqgCxX40+piNePuEsBesRbJOWSE/xX0l4lnN63zP rNulwOpHj0jxO0UYPRpWWnbbpBRRtjZ7Ad2Pr0Lr6Td2u5c4uA8uU/k3j/5ATc7Ldl ja2qEbIIh2G8Y00MsTl++oOV4QF+2L8NxS/wYDSAu2cOMojYwGP7fRx8PV1S+PPhJf eMwcpYjy4wLfip8pV0ZTrqAxTpQUf9P82fZY4js6G6bozNcuy7tmm5Q/Qm/FKQkGgz bn8l+gIiliISNvEyIeLS1tvUTztwBZWDlm9e7/nwvteVcBcutQNfuKhQ6LX2q0j+XR LrbSFl0y4fPnQ== This code was using get_user_pages*(), in a "Case 2" scenario (DMA/RDMA), using the categorization from [1]. That means that it's time to convert the get_user_pages*() + put_page() calls to pin_user_pages*() + unpin_user_pages() calls. There is some helpful background in [2]: basically, this is a small part of fixing a long-standing disconnect between pinning pages, and file systems' use of those pages. [1] Documentation/core-api/pin_user_pages.rst [2] "Explicit pinning of user-space pages": https://lwn.net/Articles/807108/ Cc: Jens Wiklander Cc: Sumit Semwal Cc: tee-dev@lists.linaro.org Cc: linux-media@vger.kernel.org Cc: dri-devel@lists.freedesktop.org Cc: linaro-mm-sig@lists.linaro.org Signed-off-by: John Hubbard --- OK, this should be indentical to v1 [1], but now rebased against Linux 5.9-rc2. As before, I've compile-tested it again with a cross compiler, but that's the only testing I'm set up for with CONFIG_TEE. [1] https://lore.kernel.org/r/20200519051850.2845561-1-jhubbard@nvidia.com thanks, John Hubbard NVIDIA drivers/tee/tee_shm.c | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-) diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c index 827ac3d0fea9..3c29e6c3ebe8 100644 --- a/drivers/tee/tee_shm.c +++ b/drivers/tee/tee_shm.c @@ -32,16 +32,13 @@ static void tee_shm_release(struct tee_shm *shm) poolm->ops->free(poolm, shm); } else if (shm->flags & TEE_SHM_REGISTER) { - size_t n; int rc = teedev->desc->ops->shm_unregister(shm->ctx, shm); if (rc) dev_err(teedev->dev.parent, "unregister shm %p failed: %d", shm, rc); - for (n = 0; n < shm->num_pages; n++) - put_page(shm->pages[n]); - + unpin_user_pages(shm->pages, shm->num_pages); kfree(shm->pages); } @@ -228,7 +225,7 @@ struct tee_shm *tee_shm_register(struct tee_context *ctx, unsigned long addr, } if (flags & TEE_SHM_USER_MAPPED) { - rc = get_user_pages_fast(start, num_pages, FOLL_WRITE, + rc = pin_user_pages_fast(start, num_pages, FOLL_WRITE, shm->pages); } else { struct kvec *kiov; @@ -292,16 +289,13 @@ struct tee_shm *tee_shm_register(struct tee_context *ctx, unsigned long addr, return shm; err: if (shm) { - size_t n; - if (shm->id >= 0) { mutex_lock(&teedev->mutex); idr_remove(&teedev->idr, shm->id); mutex_unlock(&teedev->mutex); } if (shm->pages) { - for (n = 0; n < shm->num_pages; n++) - put_page(shm->pages[n]); + unpin_user_pages(shm->pages, shm->num_pages); kfree(shm->pages); } }