From patchwork Mon Jun 18 14:17:31 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Noralf_Tr=C3=B8nnes?= X-Patchwork-Id: 10471643 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id CD62A60532 for ; Mon, 18 Jun 2018 14:18:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BD960286DF for ; Mon, 18 Jun 2018 14:18:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AEEEC289FF; Mon, 18 Jun 2018 14:18:11 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id CF7D7286DF for ; Mon, 18 Jun 2018 14:18:10 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D94056E43F; Mon, 18 Jun 2018 14:18:01 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from smtp.domeneshop.no (smtp.domeneshop.no [IPv6:2a01:5b40:0:3005::1]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8ECDD6E42D; Mon, 18 Jun 2018 14:17:59 +0000 (UTC) Received: from 211.81-166-168.customer.lyse.net ([81.166.168.211]:48974 helo=localhost.localdomain) by smtp.domeneshop.no with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_CBC_SHA256:128) (Exim 4.84_2) (envelope-from ) id 1fUuyj-00035v-N2; Mon, 18 Jun 2018 16:17:57 +0200 From: =?UTF-8?q?Noralf=20Tr=C3=B8nnes?= To: dri-devel@lists.freedesktop.org Date: Mon, 18 Jun 2018 16:17:31 +0200 Message-Id: <20180618141739.48151-5-noralf@tronnes.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20180618141739.48151-1-noralf@tronnes.org> References: <20180618141739.48151-1-noralf@tronnes.org> MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH v2 04/12] drm: Begin an API for in-kernel clients X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: intel-gfx@lists.freedesktop.org, =?UTF-8?q?Noralf=20Tr=C3=B8nnes?= , laurent.pinchart@ideasonboard.com Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP This the beginning of an API for in-kernel clients. First out is a way to get a framebuffer backed by a dumb buffer. Only GEM drivers are supported. The original idea of using an exported dma-buf was dropped because it also creates an anonomous file descriptor which doesn't work when the buffer is created from a kernel thread. The easy way out is to use drm_driver.gem_prime_vmap to get the virtual address, which requires a GEM object. This excludes the vmwgfx driver which is the only non-GEM driver apart from the legacy ones. A solution for vmwgfx will have to be worked out later if it wants to support the client API which it probably will when we have a bootsplash client. Signed-off-by: Noralf Trønnes Reviewed-by: Daniel Vetter --- Changes since version 1: - Make it possible to embed struct drm_client_dev and drop the private pointer - Use kref reference counting to control client release since both the client and the driver can release. - Add comment about using dma-buf as a possibility with some rework - Move buffer NULL check to drm_client_framebuffer_delete() - Move client name to struct drm_client_dev - Move up drm_dev_get/put calls to make them more visible - Move drm_client_dev.list definition to later patch that makes use of it Documentation/gpu/drm-client.rst | 12 ++ Documentation/gpu/index.rst | 1 + drivers/gpu/drm/Makefile | 2 +- drivers/gpu/drm/drm_client.c | 316 +++++++++++++++++++++++++++++++++++++++ drivers/gpu/drm/drm_drv.c | 1 + include/drm/drm_client.h | 87 +++++++++++ include/drm/drm_device.h | 7 + 7 files changed, 425 insertions(+), 1 deletion(-) create mode 100644 Documentation/gpu/drm-client.rst create mode 100644 drivers/gpu/drm/drm_client.c create mode 100644 include/drm/drm_client.h diff --git a/Documentation/gpu/drm-client.rst b/Documentation/gpu/drm-client.rst new file mode 100644 index 000000000000..7e672063e7eb --- /dev/null +++ b/Documentation/gpu/drm-client.rst @@ -0,0 +1,12 @@ +================= +Kernel clients +================= + +.. kernel-doc:: drivers/gpu/drm/drm_client.c + :doc: overview + +.. kernel-doc:: include/drm/drm_client.h + :internal: + +.. kernel-doc:: drivers/gpu/drm/drm_client.c + :export: diff --git a/Documentation/gpu/index.rst b/Documentation/gpu/index.rst index 00288f34c5a6..1fcf8e851e15 100644 --- a/Documentation/gpu/index.rst +++ b/Documentation/gpu/index.rst @@ -10,6 +10,7 @@ Linux GPU Driver Developer's Guide drm-kms drm-kms-helpers drm-uapi + drm-client drivers vga-switcheroo vgaarbiter diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile index ef9f3dab287f..8c8045147416 100644 --- a/drivers/gpu/drm/Makefile +++ b/drivers/gpu/drm/Makefile @@ -18,7 +18,7 @@ drm-y := drm_auth.o drm_bufs.o drm_cache.o \ drm_encoder.o drm_mode_object.o drm_property.o \ drm_plane.o drm_color_mgmt.o drm_print.o \ drm_dumb_buffers.o drm_mode_config.o drm_vblank.o \ - drm_syncobj.o drm_lease.o + drm_syncobj.o drm_lease.o drm_client.o drm-$(CONFIG_DRM_LIB_RANDOM) += lib/drm_random.o drm-$(CONFIG_DRM_VM) += drm_vm.o diff --git a/drivers/gpu/drm/drm_client.c b/drivers/gpu/drm/drm_client.c new file mode 100644 index 000000000000..98dda40f5416 --- /dev/null +++ b/drivers/gpu/drm/drm_client.c @@ -0,0 +1,316 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2018 Noralf Trønnes + */ + +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "drm_crtc_internal.h" +#include "drm_internal.h" + +/** + * DOC: overview + * + * This library provides support for clients running in the kernel like fbdev and bootsplash. + * Currently it's only partially implemented, just enough to support fbdev. + * + * GEM drivers which provide a GEM based dumb buffer with a virtual address are supported. + */ + +static int drm_client_open(struct drm_client_dev *client) +{ + struct drm_device *dev = client->dev; + struct drm_file *file; + + file = drm_file_alloc(dev->primary); + if (IS_ERR(file)) + return PTR_ERR(file); + + mutex_lock(&dev->filelist_mutex); + list_add(&file->lhead, &dev->filelist_internal); + mutex_unlock(&dev->filelist_mutex); + + client->file = file; + + return 0; +} + +/** + * drm_client_close - Close the client DRM file + * @client: DRM client + * + * Close the &drm_file that was opened by drm_client_new(). It is called + * automatically if the &drm_client_funcs.release callback is not set. + * This function should only be called from the release callback. + */ +void drm_client_close(struct drm_client_dev *client) +{ + struct drm_device *dev = client->dev; + + mutex_lock(&dev->filelist_mutex); + list_del(&client->file->lhead); + mutex_unlock(&dev->filelist_mutex); + + drm_file_free(client->file); +} +EXPORT_SYMBOL(drm_client_close); + +/** + * drm_client_new - Create a DRM client + * @dev: DRM device + * @client: DRM client + * @name: Client name + * + * Use drm_client_put() to free the client. + * + * Returns: + * Zero on success or negative error code on failure. + */ +int drm_client_new(struct drm_device *dev, struct drm_client_dev *client, + const char *name) +{ + int ret; + + if (!drm_core_check_feature(dev, DRIVER_MODESET) || + !dev->driver->dumb_create || !dev->driver->gem_prime_vmap) + return -ENOTSUPP; + + client->dev = dev; + client->name = name; + kref_init(&client->ref); + + ret = drm_client_open(client); + if (ret) + return ret; + + drm_dev_get(dev); + + return 0; +} +EXPORT_SYMBOL(drm_client_new); + +static void drm_client_release(struct kref *ref) +{ + struct drm_client_dev *client = container_of(ref, struct drm_client_dev, ref); + struct drm_device *dev = client->dev; + + DRM_DEV_DEBUG_KMS(dev->dev, "%s\n", client->name); + + drm_client_close(client); + kfree(client); + + drm_dev_put(dev); +} + +/** + * drm_client_get - Take a reference of a DRM client + * @client: DRM client (can be NULL) + * + * This increases the ref-count of @client by one. You *must* already own a + * reference when calling this. Use drm_client_put() to drop this reference + * again. + */ +void drm_client_get(struct drm_client_dev *client) +{ + if (client) + kref_get(&client->ref); +} +EXPORT_SYMBOL(drm_client_get); + +/** + * drm_client_put - Drop reference of a DRM client + * @client: DRM client (can be NULL) + * + * This decreases the ref-count of @client by one. The client resources are + * released if the ref-count drops to zero. + */ +void drm_client_put(struct drm_client_dev *client) +{ + if (client) + kref_put(&client->ref, drm_client_release); +} +EXPORT_SYMBOL(drm_client_put); + +static void drm_client_buffer_delete(struct drm_client_buffer *buffer) +{ + struct drm_device *dev; + + dev = buffer->client->dev; + if (buffer->vaddr && dev->driver->gem_prime_vunmap) + dev->driver->gem_prime_vunmap(buffer->gem, buffer->vaddr); + + if (buffer->gem) + drm_gem_object_put_unlocked(buffer->gem); + + drm_mode_destroy_dumb(dev, buffer->handle, buffer->client->file); + kfree(buffer); +} + +static struct drm_client_buffer * +drm_client_buffer_create(struct drm_client_dev *client, u32 width, u32 height, u32 format) +{ + struct drm_mode_create_dumb dumb_args = { }; + struct drm_device *dev = client->dev; + struct drm_client_buffer *buffer; + struct drm_gem_object *obj; + void *vaddr; + int ret; + + buffer = kzalloc(sizeof(*buffer), GFP_KERNEL); + if (!buffer) + return ERR_PTR(-ENOMEM); + + buffer->client = client; + + dumb_args.width = width; + dumb_args.height = height; + dumb_args.bpp = drm_format_plane_cpp(format, 0) * 8; + ret = drm_mode_create_dumb(dev, &dumb_args, client->file); + if (ret) + goto err_free; + + buffer->handle = dumb_args.handle; + buffer->pitch = dumb_args.pitch; + + obj = drm_gem_object_lookup(client->file, dumb_args.handle); + if (!obj) { + ret = -ENOENT; + goto err_delete; + } + + buffer->gem = obj; + + /* + * FIXME: The dependency on GEM here isn't required, we could + * convert the driver handle to a dma-buf instead and use the + * backend-agnostic dma-buf vmap support instead. This would + * require that the handle2fd prime ioctl is reworked to pull the + * fd_install step out of the driver backend hooks, to make that + * final step optional for internal users. + */ + vaddr = dev->driver->gem_prime_vmap(obj); + if (!vaddr) { + ret = -ENOMEM; + goto err_delete; + } + + buffer->vaddr = vaddr; + + return buffer; + +err_delete: + drm_client_buffer_delete(buffer); +err_free: + kfree(buffer); + + return ERR_PTR(ret); +} + +static void drm_client_buffer_rmfb(struct drm_client_buffer *buffer) +{ + int ret; + + if (!buffer->fb) + return; + + ret = drm_mode_rmfb(buffer->client->dev, buffer->fb->base.id, buffer->client->file); + if (ret) + DRM_DEV_ERROR(buffer->client->dev->dev, + "Error removing FB:%u (%d)\n", buffer->fb->base.id, ret); + + buffer->fb = NULL; +} + +static int drm_client_buffer_addfb(struct drm_client_buffer *buffer, + u32 width, u32 height, u32 format) +{ + struct drm_client_dev *client = buffer->client; + struct drm_mode_fb_cmd fb_req = { }; + const struct drm_format_info *info; + int ret; + + info = drm_format_info(format); + fb_req.bpp = info->cpp[0] * 8; + fb_req.depth = info->depth; + fb_req.width = width; + fb_req.height = height; + fb_req.handle = buffer->handle; + fb_req.pitch = buffer->pitch; + + ret = drm_mode_addfb(client->dev, &fb_req, client->file); + if (ret) + return ret; + + buffer->fb = drm_framebuffer_lookup(client->dev, buffer->client->file, fb_req.fb_id); + if (WARN_ON(!buffer->fb)) + return -ENOENT; + + /* drop the reference we picked up in framebuffer lookup */ + drm_framebuffer_put(buffer->fb); + + strscpy(buffer->fb->comm, client->name, TASK_COMM_LEN); + + return 0; +} + +/** + * drm_client_framebuffer_create - Create a client framebuffer + * @client: DRM client + * @width: Framebuffer width + * @height: Framebuffer height + * @format: Buffer format + * + * This function creates a &drm_client_buffer which consists of a + * &drm_framebuffer backed by a dumb buffer. + * Call drm_client_framebuffer_delete() to free the buffer. + * + * Returns: + * Pointer to a client buffer or an error pointer on failure. + */ +struct drm_client_buffer * +drm_client_framebuffer_create(struct drm_client_dev *client, u32 width, u32 height, u32 format) +{ + struct drm_client_buffer *buffer; + int ret; + + buffer = drm_client_buffer_create(client, width, height, format); + if (IS_ERR(buffer)) + return buffer; + + ret = drm_client_buffer_addfb(buffer, width, height, format); + if (ret) { + drm_client_buffer_delete(buffer); + return ERR_PTR(ret); + } + + return buffer; +} +EXPORT_SYMBOL(drm_client_framebuffer_create); + +/** + * drm_client_framebuffer_delete - Delete a client framebuffer + * @buffer: DRM client buffer (can be NULL) + */ +void drm_client_framebuffer_delete(struct drm_client_buffer *buffer) +{ + if (!buffer) + return; + + drm_client_buffer_rmfb(buffer); + drm_client_buffer_delete(buffer); +} +EXPORT_SYMBOL(drm_client_framebuffer_delete); diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c index f6910ebe4d0e..67ac793a7108 100644 --- a/drivers/gpu/drm/drm_drv.c +++ b/drivers/gpu/drm/drm_drv.c @@ -505,6 +505,7 @@ int drm_dev_init(struct drm_device *dev, dev->driver = driver; INIT_LIST_HEAD(&dev->filelist); + INIT_LIST_HEAD(&dev->filelist_internal); INIT_LIST_HEAD(&dev->ctxlist); INIT_LIST_HEAD(&dev->vmalist); INIT_LIST_HEAD(&dev->maplist); diff --git a/include/drm/drm_client.h b/include/drm/drm_client.h new file mode 100644 index 000000000000..12ac2615b17d --- /dev/null +++ b/include/drm/drm_client.h @@ -0,0 +1,87 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef _DRM_CLIENT_H_ +#define _DRM_CLIENT_H_ + +#include +#include + +struct drm_device; +struct drm_framebuffer; +struct drm_gem_object; +struct drm_minor; + +/** + * struct drm_client_dev - DRM client instance + */ +struct drm_client_dev { + /** + * @dev: DRM device + */ + struct drm_device *dev; + + /** + * @name: Name of the client. + */ + const char *name; + + /** + * @ref: + * + * Reference counting. The client resources are released when this drops + * to zero. + */ + struct kref ref; + + /** + * @file: DRM file + */ + struct drm_file *file; +}; + +void drm_client_close(struct drm_client_dev *client); +int drm_client_new(struct drm_device *dev, struct drm_client_dev *client, + const char *name); +void drm_client_get(struct drm_client_dev *client); +void drm_client_put(struct drm_client_dev *client); + +/** + * struct drm_client_buffer - DRM client buffer + */ +struct drm_client_buffer { + /** + * @client: DRM client + */ + struct drm_client_dev *client; + + /** + * @handle: Buffer handle + */ + u32 handle; + + /** + * @pitch: Buffer pitch + */ + u32 pitch; + + /** + * @gem: GEM object backing this buffer + */ + struct drm_gem_object *gem; + + /** + * @vaddr: Virtual address for the buffer + */ + void *vaddr; + + /** + * @fb: DRM framebuffer + */ + struct drm_framebuffer *fb; +}; + +struct drm_client_buffer * +drm_client_framebuffer_create(struct drm_client_dev *client, u32 width, u32 height, u32 format); +void drm_client_framebuffer_delete(struct drm_client_buffer *buffer); + +#endif diff --git a/include/drm/drm_device.h b/include/drm/drm_device.h index 858ba19a3e29..9e29976d4e98 100644 --- a/include/drm/drm_device.h +++ b/include/drm/drm_device.h @@ -74,6 +74,13 @@ struct drm_device { struct mutex filelist_mutex; struct list_head filelist; + /** + * @filelist_internal: + * + * List of open DRM files for in-kernel clients. Protected by @filelist_mutex. + */ + struct list_head filelist_internal; + /** \name Memory management */ /*@{ */ struct list_head maplist; /**< Linked list of regions */