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=-8.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 15DADC10F14 for ; Tue, 16 Apr 2019 18:39:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D139F206BA for ; Tue, 16 Apr 2019 18:39:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="h3e1Nm3R" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730546AbfDPSjj (ORCPT ); Tue, 16 Apr 2019 14:39:39 -0400 Received: from mail-wm1-f68.google.com ([209.85.128.68]:37966 "EHLO mail-wm1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730348AbfDPSix (ORCPT ); Tue, 16 Apr 2019 14:38:53 -0400 Received: by mail-wm1-f68.google.com with SMTP id w15so290951wmc.3; Tue, 16 Apr 2019 11:38:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=TLleK0VtrURc8NakouQBGkqZbPDHg07f9BvqliSxF70=; b=h3e1Nm3R3xsbD+PYUqSpNvsqvv25b71V1k+JePPL/XPpDetWnd7J/zs42/KuJEfJGF S9MVNlIxKBIr/pxNEFOa7GVi+5nYrR3xQQgIRMCBdti8z6/C2FkP5W1ZhONqzIGoXd/p joJoIrnNevNZVJuInDW7FJNIlEtpaHygBfUS/dFzlUCrAHNTdQlVprBu+rtP8RR6/yUr ByNbE8HMarmtuTKhwQhx9TG1Ukycwhdhgb76FVzBL9wRYQhWF3ZLB7wapcE1sIXCfUpM hXkRscYpsz9Zbl4yBd2ABW0K5gbKn3MNDCTGJ+E39/cU69vsf09kV5AxUfsOEFCPWRZV UO7g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=TLleK0VtrURc8NakouQBGkqZbPDHg07f9BvqliSxF70=; b=TFMEIalIJRUTUAj7XZFZDWvWdfVQmgnbvi0kb0xmCmHp5oRFA2/GmXBICgeBYChwXO Q44TxoQEFf5/aqDBsWvLl97BzmPegW08KkZ8LprFlI08cMVgfh2z59un2zjzeykzlNAv J7poMM/oB9PdlQ5mP+wmNZgC/PfKoHhPnuTOwss3QNa/X4N3I2fn7W3j7Bi9NxcNVeqg v2EIQmNEMApzyO8Si6kBnXwpuaiwf8S8hjV4jqq3pWH3IjsNPWvUpgKYYkwjZvHicHQF a1fkaHejipVStYMONBebrLaL3ppKUh0SYyfjYgx/VWQ/dlYaiV+AXfVTfwMwLpLY2nVW iQnw== X-Gm-Message-State: APjAAAUGPHFzim33sz87Stx/lteDFnzmVh1DQ2zrTm90apTu0zIY/Pu1 RTdhUHZFjBKr5RaeGbGXtn61a0ZZ X-Google-Smtp-Source: APXvYqz07VW+fNme+N9AqBbL6HOJCdOJCyAxD2ZszHK1Hf1dhl/j/yKTr8NoWJMd6oM74U0ThWkt2w== X-Received: by 2002:a1c:eb07:: with SMTP id j7mr26684391wmh.138.1555439931201; Tue, 16 Apr 2019 11:38:51 -0700 (PDT) Received: from abel.fritz.box ([2a02:908:1252:fb60:fcfa:e34f:82c0:3f66]) by smtp.gmail.com with ESMTPSA id m13sm128823wmg.42.2019.04.16.11.38.50 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 16 Apr 2019 11:38:50 -0700 (PDT) From: "=?UTF-8?q?Christian=20K=C3=B6nig?=" X-Google-Original-From: =?UTF-8?q?Christian=20K=C3=B6nig?= To: sumit.semwal@linaro.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org Subject: [PATCH 05/12] dma-buf: add explicit buffer pinning Date: Tue, 16 Apr 2019 20:38:34 +0200 Message-Id: <20190416183841.1577-6-christian.koenig@amd.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190416183841.1577-1-christian.koenig@amd.com> References: <20190416183841.1577-1-christian.koenig@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add optional explicit pinning callbacks instead of implicitly assume the exporter pins the buffer when a mapping is created. Signed-off-by: Christian König --- drivers/dma-buf/dma-buf.c | 39 +++++++++++++++++++++++++++++++++++++++ include/linux/dma-buf.h | 37 +++++++++++++++++++++++++++++++------ 2 files changed, 70 insertions(+), 6 deletions(-) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index a3738fab3927..f23ff8355505 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -630,6 +630,41 @@ void dma_buf_detach(struct dma_buf *dmabuf, struct dma_buf_attachment *attach) } EXPORT_SYMBOL_GPL(dma_buf_detach); +/** + * dma_buf_pin - Lock down the DMA-buf + * + * @dmabuf: [in] DMA-buf to lock down. + * + * Returns: + * 0 on success, negative error code on failure. + */ +int dma_buf_pin(struct dma_buf *dmabuf) +{ + int ret = 0; + + reservation_object_assert_held(dmabuf->resv); + + if (dmabuf->ops->pin) + ret = dmabuf->ops->pin(dmabuf); + + return ret; +} +EXPORT_SYMBOL_GPL(dma_buf_pin); + +/** + * dma_buf_unpin - Remove lock from DMA-buf + * + * @dmabuf: [in] DMA-buf to unlock. + */ +void dma_buf_unpin(struct dma_buf *dmabuf) +{ + reservation_object_assert_held(dmabuf->resv); + + if (dmabuf->ops->unpin) + dmabuf->ops->unpin(dmabuf); +} +EXPORT_SYMBOL_GPL(dma_buf_unpin); + /** * dma_buf_map_attachment_locked - Maps the buffer into _device_ address space * with the reservation lock held. Is a wrapper for map_dma_buf() of the @@ -666,6 +701,8 @@ dma_buf_map_attachment_locked(struct dma_buf_attachment *attach, */ if (attach->invalidate) list_del(&attach->node); + else + dma_buf_pin(attach->dmabuf); sg_table = attach->dmabuf->ops->map_dma_buf(attach, direction); if (attach->invalidate) list_add(&attach->node, &attach->dmabuf->attachments); @@ -735,6 +772,8 @@ void dma_buf_unmap_attachment_locked(struct dma_buf_attachment *attach, attach->dmabuf->ops->unmap_dma_buf(attach, sg_table, direction); + if (!attach->invalidate) + dma_buf_unpin(attach->dmabuf); } EXPORT_SYMBOL_GPL(dma_buf_unmap_attachment_locked); diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index ece4638359a8..a615b74e5894 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -100,14 +100,40 @@ struct dma_buf_ops { */ void (*detach)(struct dma_buf *, struct dma_buf_attachment *); + /** + * @pin_dma_buf: + * + * This is called by dma_buf_pin and lets the exporter know that an + * importer assumes that the DMA-buf can't be invalidated any more. + * + * This is called with the dmabuf->resv object locked. + * + * This callback is optional. + * + * Returns: + * + * 0 on success, negative error code on failure. + */ + int (*pin)(struct dma_buf *); + + /** + * @unpin_dma_buf: + * + * This is called by dma_buf_unpin and lets the exporter know that an + * importer doesn't need to the DMA-buf to stay were it is any more. + * + * This is called with the dmabuf->resv object locked. + * + * This callback is optional. + */ + void (*unpin)(struct dma_buf *); + /** * @map_dma_buf: * * This is called by dma_buf_map_attachment() and is used to map a * shared &dma_buf into device address space, and it is mandatory. It - * can only be called if @attach has been called successfully. This - * essentially pins the DMA buffer into place, and it cannot be moved - * any more + * can only be called if @attach has been called successfully. * * This call may sleep, e.g. when the backing storage first needs to be * allocated, or moved to a location suitable for all currently attached @@ -148,9 +174,6 @@ struct dma_buf_ops { * * This is called by dma_buf_unmap_attachment() and should unmap and * release the &sg_table allocated in @map_dma_buf, and it is mandatory. - * It should also unpin the backing storage if this is the last mapping - * of the DMA buffer, it the exporter supports backing storage - * migration. * * This is always called with the dmabuf->resv object locked when * no_sgt_cache is true. @@ -442,6 +465,8 @@ int dma_buf_fd(struct dma_buf *dmabuf, int flags); struct dma_buf *dma_buf_get(int fd); void dma_buf_put(struct dma_buf *dmabuf); +int dma_buf_pin(struct dma_buf *dmabuf); +void dma_buf_unpin(struct dma_buf *dmabuf); struct sg_table *dma_buf_map_attachment_locked(struct dma_buf_attachment *, enum dma_data_direction); struct sg_table *dma_buf_map_attachment(struct dma_buf_attachment *, -- 2.17.1