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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 44450C3ABAA for ; Fri, 2 May 2025 15:31:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=rBb2/F0SWaaL//2nszq7lcMRi0ukaEFUfCYYjCSvGy4=; b=bU9eMj8PX3eYWxGB48iGPzWvNP A60Q4OR8iGgmNIKRxGlyDy5eiy2JqA7zXdRZ7SbyWf+6uxhCldKTapKwMELjvlnB/jNgn1K+DtWLO 9HAx9psk57QKXICAZATbMkMqSGF1SByfJHb0gVILMLhL8/i4J+H/Z2LawgLXQHHlUrirh4qvMwB9r NtiMc7F3W8ABPeBtus198dwc9P/D5wiMb7Cre72DQoEWZgA2u1dkHzwxVI+n77p63MxA80kbIZXNh x8VgKdXtC9g6XmJkMNNwKH7Mgo/IfJ/J4jKCxZ9ERrHXPYQa5QkCfJZtRrJ05zJn7oAQL4uTyO/WN KZbPxJXw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uAsMZ-00000002LQX-1mvo; Fri, 02 May 2025 15:31:43 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uAs35-00000002Iez-3K7O for linux-arm-kernel@lists.infradead.org; Fri, 02 May 2025 15:11:37 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 52B951688; Fri, 2 May 2025 08:11:26 -0700 (PDT) Received: from [10.1.196.40] (e121345-lin.cambridge.arm.com [10.1.196.40]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 86C713F66E; Fri, 2 May 2025 08:11:28 -0700 (PDT) Message-ID: <4b2f7c31-c61b-45d8-b32e-16bb91c4289b@arm.com> Date: Fri, 2 May 2025 16:11:26 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v8 11/14] tee: add tee_shm_alloc_cma_phys_mem() To: Jens Wiklander , linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, op-tee@lists.trustedfirmware.org, linux-arm-kernel@lists.infradead.org Cc: Olivier Masse , Thierry Reding , Yong Wu , Sumit Semwal , Benjamin Gaignard , Brian Starkey , John Stultz , "T . J . Mercier" , =?UTF-8?Q?Christian_K=C3=B6nig?= , Sumit Garg , Matthias Brugger , AngeloGioacchino Del Regno , azarrabi@qti.qualcomm.com, Simona Vetter , Daniel Stone , Rouven Czerwinski References: <20250502100049.1746335-1-jens.wiklander@linaro.org> <20250502100049.1746335-12-jens.wiklander@linaro.org> From: Robin Murphy Content-Language: en-GB In-Reply-To: <20250502100049.1746335-12-jens.wiklander@linaro.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250502_081136_073521_B375EDA7 X-CRM114-Status: GOOD ( 24.97 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 02/05/2025 10:59 am, Jens Wiklander wrote: > Add tee_shm_alloc_cma_phys_mem() to allocate a physical memory using > from the default CMA pool. The memory is represented by a tee_shm object > using the new flag TEE_SHM_CMA_BUF to identify it as physical memory > from CMA. If and when it's possible to dynamically delegate any old kernel memory to the TEE, it's far from clear why that should involve poking around in CMA internals... > Signed-off-by: Jens Wiklander > --- > drivers/tee/tee_shm.c | 55 ++++++++++++++++++++++++++++++++++++++-- > include/linux/tee_core.h | 4 +++ > 2 files changed, 57 insertions(+), 2 deletions(-) > > diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c > index e1ed52ee0a16..faaa0a87bb18 100644 > --- a/drivers/tee/tee_shm.c > +++ b/drivers/tee/tee_shm.c > @@ -3,8 +3,11 @@ > * Copyright (c) 2015-2017, 2019-2021 Linaro Limited > */ > #include > +#include > #include > #include > +#include > +#include > #include > #include > #include > @@ -13,7 +16,6 @@ > #include > #include > #include > -#include > #include "tee_private.h" > > static void shm_put_kernel_pages(struct page **pages, size_t page_count) > @@ -49,7 +51,14 @@ static void tee_shm_release(struct tee_device *teedev, struct tee_shm *shm) > struct tee_shm *parent_shm = NULL; > void *p = shm; > > - if (shm->flags & TEE_SHM_DMA_BUF) { > + if (shm->flags & TEE_SHM_CMA_BUF) { > +#if IS_ENABLED(CONFIG_CMA) > + struct page *page = phys_to_page(shm->paddr); > + struct cma *cma = dev_get_cma_area(&shm->ctx->teedev->dev); If you want dma_contiguous_default_area as the commit message implies, use dma_contiguous_default_area. Appearing to support per-device CMA pools but relying on the device not having one is pretty yucky. But again, why? If you want page-backed DMA-able memory, with all the other assumptions being made here, you may as well just rely on dma_alloc_pages(DMA_ATTR_SKIP_CPU_SYNC) doing what you want, while also being potentially more flexible for !CMA and non-invasive. Or at the very least, could the TEE delegation not be composed on top of the existing CMA heap allocator? Thanks, Robin. > + > + cma_release(cma, page, shm->size / PAGE_SIZE); > +#endif > + } else if (shm->flags & TEE_SHM_DMA_BUF) { > struct tee_shm_dmabuf_ref *ref; > > ref = container_of(shm, struct tee_shm_dmabuf_ref, shm); > @@ -306,6 +315,48 @@ struct tee_shm *tee_shm_alloc_priv_buf(struct tee_context *ctx, size_t size) > } > EXPORT_SYMBOL_GPL(tee_shm_alloc_priv_buf); > > +struct tee_shm *tee_shm_alloc_cma_phys_mem(struct tee_context *ctx, > + size_t page_count, size_t align) > +{ > +#if IS_ENABLED(CONFIG_CMA) > + struct tee_device *teedev = ctx->teedev; > + struct cma *cma = dev_get_cma_area(&teedev->dev); > + struct tee_shm *shm; > + struct page *page; > + > + if (!tee_device_get(teedev)) > + return ERR_PTR(-EINVAL); > + > + page = cma_alloc(cma, page_count, align, true/*no_warn*/); > + if (!page) > + goto err_put_teedev; > + > + shm = kzalloc(sizeof(*shm), GFP_KERNEL); > + if (!shm) > + goto err_cma_crelease; > + > + refcount_set(&shm->refcount, 1); > + shm->ctx = ctx; > + shm->paddr = page_to_phys(page); > + shm->size = page_count * PAGE_SIZE; > + shm->flags = TEE_SHM_CMA_BUF; > + > + teedev_ctx_get(ctx); > + > + return shm; > + > +err_cma_crelease: > + cma_release(cma, page, page_count); > +err_put_teedev: > + tee_device_put(teedev); > + > + return ERR_PTR(-ENOMEM); > +#else > + return ERR_PTR(-EINVAL); > +#endif > +} > +EXPORT_SYMBOL_GPL(tee_shm_alloc_cma_phys_mem); > + > int tee_dyn_shm_alloc_helper(struct tee_shm *shm, size_t size, size_t align, > int (*shm_register)(struct tee_context *ctx, > struct tee_shm *shm, > diff --git a/include/linux/tee_core.h b/include/linux/tee_core.h > index 02c07f661349..3a4e1b00fcc7 100644 > --- a/include/linux/tee_core.h > +++ b/include/linux/tee_core.h > @@ -29,6 +29,7 @@ > #define TEE_SHM_POOL BIT(2) /* Memory allocated from pool */ > #define TEE_SHM_PRIV BIT(3) /* Memory private to TEE driver */ > #define TEE_SHM_DMA_BUF BIT(4) /* Memory with dma-buf handle */ > +#define TEE_SHM_CMA_BUF BIT(5) /* CMA allocated memory */ > > #define TEE_DEVICE_FLAG_REGISTERED 0x1 > #define TEE_MAX_DEV_NAME_LEN 32 > @@ -310,6 +311,9 @@ void *tee_get_drvdata(struct tee_device *teedev); > */ > struct tee_shm *tee_shm_alloc_priv_buf(struct tee_context *ctx, size_t size); > > +struct tee_shm *tee_shm_alloc_cma_phys_mem(struct tee_context *ctx, > + size_t page_count, size_t align); > + > int tee_dyn_shm_alloc_helper(struct tee_shm *shm, size_t size, size_t align, > int (*shm_register)(struct tee_context *ctx, > struct tee_shm *shm,