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 58BB9C71136 for ; Tue, 17 Jun 2025 11:02:47 +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:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=XwiUi0jOxwK2QebCl85Ki9WTVfsTLa6zJXPwoGiOSPU=; b=13wI3dn4KafA68XYkQafi3MVan 9j4By1pM0hzWqn/76YS2J5wPTQSlIg1tNzadTfFxp7a+Fx1uRfCFEo8OP/aaCPBqz3ID1mVOX4nXP tJUUx3tVBTg+W2CP5voXIwlKgYKnshoxBuYmsgXJNDwc1HFoZfcuWT6Ln3fKaVQc+Mj/EGqOtVwmh WeBA5UN8/qumQR6C+LH7bxLQ3s25GcNwPgGD9Cz9H8imXswouZ6AiZlptfgahFECGY5MDQjVS00nr r5/0vJ9EKmmRhDjHmtD80McIs9u9pbJKNZwxHQHuDzu/rKH8mI9eRQv/qXORz1k3LrzhU2A2/mS3Z jXxC3bvQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uRU5O-0000000704M-03ez; Tue, 17 Jun 2025 11:02:38 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uRTrx-00000006xvw-1CS1 for linux-arm-kernel@lists.infradead.org; Tue, 17 Jun 2025 10:48:46 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id D0DD65C65E5; Tue, 17 Jun 2025 10:46:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4B91FC4CEE3; Tue, 17 Jun 2025 10:48:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1750157324; bh=ZHgEWNgwSmV8C8MoKIwnV2SrNzb6bAZ1fpff2pRc0FQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=U5Oi1J/LXfcKUKOr7i5zcezRxACc6kUd9g/hN6XVV5uoRD7AtJfVU7FzoPnyzOYRN AwOIgcLSLs2YRLE2for1OnbsRzU6PnDet202Gvgt2F7ZurH+oMzwe2yVhh4mMfvZRM xX8Fk1dC5HVp2spQuhSoOPvvDaNk/EE2uFBPg6SKKwLoCfUMBoud2AlGFFG6US4SNP UEShUMa9Abd/MAo+Qp51dOVo9pLK/qhHwYrlVuo6MEvnwSQWW/IEcRJP8mau8BsBD4 Y73XFzX/1iapUEV2evKhBzLDlK0bhwoQUXivFH9Q7hxuEN3UOfhb1MmmI6+wUwSWWG 3OCF62wIEZ4XA== Date: Tue, 17 Jun 2025 16:18:34 +0530 From: Sumit Garg To: Jens Wiklander Cc: 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, Olivier Masse , Thierry Reding , Yong Wu , Sumit Semwal , Benjamin Gaignard , Brian Starkey , John Stultz , "T . J . Mercier" , Christian =?iso-8859-1?Q?K=F6nig?= , Matthias Brugger , AngeloGioacchino Del Regno , azarrabi@qti.qualcomm.com, Simona Vetter , Daniel Stone , Rouven Czerwinski , robin.murphy@arm.com, Etienne Carriere Subject: Re: [PATCH v10 5/9] tee: new ioctl to a register tee_shm from a dmabuf file descriptor Message-ID: References: <20250610131600.2972232-1-jens.wiklander@linaro.org> <20250610131600.2972232-6-jens.wiklander@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250610131600.2972232-6-jens.wiklander@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250617_034845_414488_D67F7262 X-CRM114-Status: GOOD ( 47.49 ) 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 Tue, Jun 10, 2025 at 03:13:49PM +0200, Jens Wiklander wrote: > From: Etienne Carriere > > Add a userspace API to create a tee_shm object that refers to a dmabuf > reference. > > Userspace registers the dmabuf file descriptor as in a tee_shm object. > The registration is completed with a tee_shm returned file descriptor. > > Userspace is free to close the dmabuf file descriptor after it has been > registered since all the resources are now held via the new tee_shm > object. > > Closing the tee_shm file descriptor will eventually release all > resources used by the tee_shm object when all references are released. > > The new IOCTL, TEE_IOC_SHM_REGISTER_FD, supports dmabuf references to > physically contiguous memory buffers. Dmabuf references acquired from > the TEE DMA-heap can be used as protected memory for Secure Video Path > and such use cases. It depends on the TEE and the TEE driver if dmabuf > references acquired by other means can be used. > > A new tee_shm flag is added to identify tee_shm objects built from a > registered dmabuf, TEE_SHM_DMA_BUF. > > Signed-off-by: Etienne Carriere > Signed-off-by: Olivier Masse > Signed-off-by: Jens Wiklander > --- > drivers/tee/tee_core.c | 63 +++++++++++++++++++++- > drivers/tee/tee_private.h | 10 ++++ > drivers/tee/tee_shm.c | 106 ++++++++++++++++++++++++++++++++++++-- > include/linux/tee_core.h | 1 + > include/linux/tee_drv.h | 10 ++++ > include/uapi/linux/tee.h | 31 +++++++++++ > 6 files changed, 217 insertions(+), 4 deletions(-) > > diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c > index 5259b8223c27..0e9d9e5872a4 100644 > --- a/drivers/tee/tee_core.c > +++ b/drivers/tee/tee_core.c > @@ -353,11 +353,49 @@ tee_ioctl_shm_register(struct tee_context *ctx, > return ret; > } > > +static int > +tee_ioctl_shm_register_fd(struct tee_context *ctx, > + struct tee_ioctl_shm_register_fd_data __user *udata) > +{ > + struct tee_ioctl_shm_register_fd_data data; > + struct tee_shm *shm; > + long ret; > + > + if (copy_from_user(&data, udata, sizeof(data))) > + return -EFAULT; > + > + /* Currently no input flags are supported */ > + if (data.flags) > + return -EINVAL; > + > + shm = tee_shm_register_fd(ctx, data.fd); > + if (IS_ERR(shm)) > + return -EINVAL; > + > + data.id = shm->id; > + data.flags = shm->flags; > + data.size = shm->size; > + > + if (copy_to_user(udata, &data, sizeof(data))) > + ret = -EFAULT; > + else > + ret = tee_shm_get_fd(shm); > + > + /* > + * When user space closes the file descriptor the shared memory > + * should be freed or if tee_shm_get_fd() failed then it will > + * be freed immediately. > + */ > + tee_shm_put(shm); > + return ret; > +} > + > static int param_from_user_memref(struct tee_context *ctx, > struct tee_param_memref *memref, > struct tee_ioctl_param *ip) > { > struct tee_shm *shm; > + size_t offs = 0; > > /* > * If a NULL pointer is passed to a TA in the TEE, > @@ -388,6 +426,26 @@ static int param_from_user_memref(struct tee_context *ctx, > tee_shm_put(shm); > return -EINVAL; > } > + > + if (shm->flags & TEE_SHM_DMA_BUF) { > + struct tee_shm_dmabuf_ref *ref; > + > + ref = container_of(shm, struct tee_shm_dmabuf_ref, shm); > + if (ref->parent_shm) { > + /* > + * The shm already has one reference to > + * ref->parent_shm so we are clear of 0. > + * We're getting another reference since > + * this shm will be used in the parameter > + * list instead of the shm we got with > + * tee_shm_get_from_id() above. > + */ > + refcount_inc(&ref->parent_shm->refcount); > + tee_shm_put(shm); > + shm = ref->parent_shm; > + offs = ref->offset; > + } > + } > } else if (ctx->cap_memref_null) { > /* Pass NULL pointer to OP-TEE */ > shm = NULL; > @@ -395,7 +453,7 @@ static int param_from_user_memref(struct tee_context *ctx, > return -EINVAL; > } > > - memref->shm_offs = ip->a; > + memref->shm_offs = ip->a + offs; > memref->size = ip->b; > memref->shm = shm; > > @@ -841,6 +899,8 @@ static long tee_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > return tee_ioctl_shm_alloc(ctx, uarg); > case TEE_IOC_SHM_REGISTER: > return tee_ioctl_shm_register(ctx, uarg); > + case TEE_IOC_SHM_REGISTER_FD: > + return tee_ioctl_shm_register_fd(ctx, uarg); > case TEE_IOC_OPEN_SESSION: > return tee_ioctl_open_session(ctx, uarg); > case TEE_IOC_INVOKE: > @@ -1300,3 +1360,4 @@ MODULE_AUTHOR("Linaro"); > MODULE_DESCRIPTION("TEE Driver"); > MODULE_VERSION("1.0"); > MODULE_LICENSE("GPL v2"); > +MODULE_IMPORT_NS("DMA_BUF"); > diff --git a/drivers/tee/tee_private.h b/drivers/tee/tee_private.h > index 6c6ff5d5eed2..308467705da6 100644 > --- a/drivers/tee/tee_private.h > +++ b/drivers/tee/tee_private.h > @@ -13,6 +13,16 @@ > #include > #include > > +/* extra references appended to shm object for registered shared memory */ > +struct tee_shm_dmabuf_ref { > + struct tee_shm shm; > + size_t offset; > + struct dma_buf *dmabuf; > + struct dma_buf_attachment *attach; > + struct sg_table *sgt; > + struct tee_shm *parent_shm; > +}; > + > int tee_shm_get_fd(struct tee_shm *shm); > > bool tee_device_get(struct tee_device *teedev); > diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c > index daf6e5cfd59a..e63095e84644 100644 > --- a/drivers/tee/tee_shm.c > +++ b/drivers/tee/tee_shm.c > @@ -4,6 +4,7 @@ > */ > #include > #include > +#include > #include > #include > #include > @@ -45,7 +46,21 @@ static void release_registered_pages(struct tee_shm *shm) > > static void tee_shm_release(struct tee_device *teedev, struct tee_shm *shm) > { > - if (shm->flags & TEE_SHM_POOL) { > + void *p = shm; > + > + if (shm->flags & TEE_SHM_DMA_BUF) { > + struct tee_shm_dmabuf_ref *ref; > + > + ref = container_of(shm, struct tee_shm_dmabuf_ref, shm); > + p = ref; > + if (ref->attach) { > + dma_buf_unmap_attachment(ref->attach, ref->sgt, > + DMA_BIDIRECTIONAL); > + > + dma_buf_detach(ref->dmabuf, ref->attach); > + } > + dma_buf_put(ref->dmabuf); > + } else if (shm->flags & TEE_SHM_POOL) { > teedev->pool->ops->free(teedev->pool, shm); > } else if (shm->flags & TEE_SHM_DYNAMIC) { > int rc = teedev->desc->ops->shm_unregister(shm->ctx, shm); > @@ -59,7 +74,7 @@ static void tee_shm_release(struct tee_device *teedev, struct tee_shm *shm) > > teedev_ctx_put(shm->ctx); > > - kfree(shm); > + kfree(p); > > tee_device_put(teedev); > } > @@ -169,7 +184,7 @@ struct tee_shm *tee_shm_alloc_user_buf(struct tee_context *ctx, size_t size) > * tee_client_invoke_func(). The memory allocated is later freed with a > * call to tee_shm_free(). > * > - * @returns a pointer to 'struct tee_shm' > + * @returns a pointer to 'struct tee_shm' on success, and ERR_PTR on failure > */ > struct tee_shm *tee_shm_alloc_kernel_buf(struct tee_context *ctx, size_t size) > { > @@ -179,6 +194,91 @@ struct tee_shm *tee_shm_alloc_kernel_buf(struct tee_context *ctx, size_t size) > } > EXPORT_SYMBOL_GPL(tee_shm_alloc_kernel_buf); > > +struct tee_shm *tee_shm_register_fd(struct tee_context *ctx, int fd) > +{ > + struct tee_shm_dmabuf_ref *ref; > + int rc; > + > + if (!tee_device_get(ctx->teedev)) > + return ERR_PTR(-EINVAL); > + > + teedev_ctx_get(ctx); > + > + ref = kzalloc(sizeof(*ref), GFP_KERNEL); > + if (!ref) { > + rc = -ENOMEM; > + goto err_put_tee; > + } > + > + refcount_set(&ref->shm.refcount, 1); > + ref->shm.ctx = ctx; > + ref->shm.id = -1; > + ref->shm.flags = TEE_SHM_DMA_BUF; > + > + ref->dmabuf = dma_buf_get(fd); > + if (IS_ERR(ref->dmabuf)) { > + rc = PTR_ERR(ref->dmabuf); > + goto err_kfree_ref; > + } > + > + rc = tee_heap_update_from_dma_buf(ctx->teedev, ref->dmabuf, > + &ref->offset, &ref->shm, > + &ref->parent_shm); > + if (!rc) > + goto out; One odd thing I find here, why do we bail out on success case here? Don't we need the DMA buffer attach and map APIs to be invoked on success case here? -Sumit > + if (rc != -EINVAL) > + goto err_put_dmabuf; > + > + ref->attach = dma_buf_attach(ref->dmabuf, &ctx->teedev->dev); > + if (IS_ERR(ref->attach)) { > + rc = PTR_ERR(ref->attach); > + goto err_put_dmabuf; > + } > + > + ref->sgt = dma_buf_map_attachment(ref->attach, DMA_BIDIRECTIONAL); > + if (IS_ERR(ref->sgt)) { > + rc = PTR_ERR(ref->sgt); > + goto err_detach; > + } > + > + if (sg_nents(ref->sgt->sgl) != 1) { > + rc = -EINVAL; > + goto err_unmap_attachement; > + } > + > + ref->shm.paddr = page_to_phys(sg_page(ref->sgt->sgl)); > + ref->shm.size = ref->sgt->sgl->length; > + > +out: > + mutex_lock(&ref->shm.ctx->teedev->mutex); > + ref->shm.id = idr_alloc(&ref->shm.ctx->teedev->idr, &ref->shm, > + 1, 0, GFP_KERNEL); > + mutex_unlock(&ref->shm.ctx->teedev->mutex); > + if (ref->shm.id < 0) { > + rc = ref->shm.id; > + if (ref->attach) > + goto err_unmap_attachement; > + goto err_put_dmabuf; > + } > + > + return &ref->shm; > + > +err_unmap_attachement: > + dma_buf_unmap_attachment(ref->attach, ref->sgt, DMA_BIDIRECTIONAL); > +err_detach: > + dma_buf_detach(ref->dmabuf, ref->attach); > +err_put_dmabuf: > + dma_buf_put(ref->dmabuf); > +err_kfree_ref: > + kfree(ref); > +err_put_tee: > + teedev_ctx_put(ctx); > + tee_device_put(ctx->teedev); > + > + return ERR_PTR(rc); > +} > +EXPORT_SYMBOL_GPL(tee_shm_register_fd); > + > /** > * tee_shm_alloc_priv_buf() - Allocate shared memory for a privately shared > * kernel buffer > diff --git a/include/linux/tee_core.h b/include/linux/tee_core.h > index 22e03d897dc3..f17710196c4c 100644 > --- a/include/linux/tee_core.h > +++ b/include/linux/tee_core.h > @@ -28,6 +28,7 @@ > #define TEE_SHM_USER_MAPPED BIT(1) /* Memory mapped in user space */ > #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_DEVICE_FLAG_REGISTERED 0x1 > #define TEE_MAX_DEV_NAME_LEN 32 > diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h > index a54c203000ed..824f1251de60 100644 > --- a/include/linux/tee_drv.h > +++ b/include/linux/tee_drv.h > @@ -116,6 +116,16 @@ struct tee_shm *tee_shm_alloc_kernel_buf(struct tee_context *ctx, size_t size); > struct tee_shm *tee_shm_register_kernel_buf(struct tee_context *ctx, > void *addr, size_t length); > > +/** > + * tee_shm_register_fd() - Register shared memory from file descriptor > + * > + * @ctx: Context that allocates the shared memory > + * @fd: Shared memory file descriptor reference > + * > + * @returns a pointer to 'struct tee_shm' on success, and ERR_PTR on failure > + */ > +struct tee_shm *tee_shm_register_fd(struct tee_context *ctx, int fd); > + > /** > * tee_shm_free() - Free shared memory > * @shm: Handle to shared memory to free > diff --git a/include/uapi/linux/tee.h b/include/uapi/linux/tee.h > index d0430bee8292..d843cf980d98 100644 > --- a/include/uapi/linux/tee.h > +++ b/include/uapi/linux/tee.h > @@ -378,6 +378,37 @@ struct tee_ioctl_shm_register_data { > __s32 id; > }; > > +/** > + * struct tee_ioctl_shm_register_fd_data - Shared memory registering argument > + * @fd: [in] File descriptor identifying dmabuf reference > + * @size: [out] Size of referenced memory > + * @flags: [in] Flags to/from allocation. > + * @id: [out] Identifier of the shared memory > + * > + * The flags field should currently be zero as input. Updated by the call > + * with actual flags as defined by TEE_IOCTL_SHM_* above. > + * This structure is used as argument for TEE_IOC_SHM_REGISTER_FD below. > + */ > +struct tee_ioctl_shm_register_fd_data { > + __s64 fd; > + __u64 size; > + __u32 flags; > + __s32 id; > +}; > + > +/** > + * TEE_IOC_SHM_REGISTER_FD - register a shared memory from a file descriptor > + * > + * Returns a file descriptor on success or < 0 on failure > + * > + * The returned file descriptor refers to the shared memory object in the > + * kernel. The supplied file deccriptor can be closed if it's not needed > + * for other purposes. The shared memory is freed when the descriptor is > + * closed. > + */ > +#define TEE_IOC_SHM_REGISTER_FD _IOWR(TEE_IOC_MAGIC, TEE_IOC_BASE + 8, \ > + struct tee_ioctl_shm_register_fd_data) > + > /** > * TEE_IOC_SHM_REGISTER - Register shared memory argument > * > -- > 2.43.0 >