From patchwork Mon Nov 18 20:23:28 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Stultz X-Patchwork-Id: 11250257 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 1CB3D138C for ; Mon, 18 Nov 2019 20:23:53 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 05125208A1 for ; Mon, 18 Nov 2019 20:23:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 05125208A1 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A4F1D6E828; Mon, 18 Nov 2019 20:23:49 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail-pf1-x443.google.com (mail-pf1-x443.google.com [IPv6:2607:f8b0:4864:20::443]) by gabe.freedesktop.org (Postfix) with ESMTPS id D3C716E824 for ; Mon, 18 Nov 2019 20:23:38 +0000 (UTC) Received: by mail-pf1-x443.google.com with SMTP id q26so10899773pfn.11 for ; Mon, 18 Nov 2019 12:23:38 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=XN4hvqlb6QwR+n0vciVQe9k2LrVf8lKqLorXGthsEfQ=; b=ft8iIaxHAuazShwkYayx5DxO0MDYgIXtiqGOYnWekQmDOBOBy2XE/icUeT3YxrPYjY gHzN4T6TIcjw6XsT78WJYgtIxUSU64qavpWAIyenx5X3b4+XWh0HdHqgXz/kjddJosH1 lDxZi6AqOMDXmXVHU/cbayZcHz/zWHPnsqNaLYVrUNCf7WAxUUfX28Wl98bJa0MCS4uA PuQj+M32aIGJT/WRfKAvFECQuyaDEzuJS99uET2IRKK1LjETF6Ui80CbixYydCnBlgk9 e42a3pFoPAyW0shILFBEz7CjRgwTFWT6F6vVQznlnj10IhzpvznJgH2wEtAVMCvNl8gX 5+Dw== X-Gm-Message-State: APjAAAXBtsf7IwsAw1+JZyapnJzG1XlaomyQEsSqfJm54VhSjQbrl8hX mwkKQVIg2bniQ2rLTbvXRy8eFQ== X-Google-Smtp-Source: APXvYqwOdxNT/v1Qfqiy1/jqPDrYVW2ZhD5ovKj460A5TrFQBnzQEmPKb23ahZf6eKwaFOMS+/eEBA== X-Received: by 2002:a63:204e:: with SMTP id r14mr1286654pgm.101.1574108616815; Mon, 18 Nov 2019 12:23:36 -0800 (PST) Received: from localhost.localdomain (c-67-170-172-113.hsd1.or.comcast.net. [67.170.172.113]) by smtp.gmail.com with ESMTPSA id 7sm11021871pgk.25.2019.11.18.12.23.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 18 Nov 2019 12:23:36 -0800 (PST) From: John Stultz To: lkml Subject: [PATCH v16 1/5] dma-buf: Add dma-buf heaps framework Date: Mon, 18 Nov 2019 20:23:28 +0000 Message-Id: <20191118202332.109172-2-john.stultz@linaro.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20191118202332.109172-1-john.stultz@linaro.org> References: <20191118202332.109172-1-john.stultz@linaro.org> X-Mailman-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=XN4hvqlb6QwR+n0vciVQe9k2LrVf8lKqLorXGthsEfQ=; b=pVV1bwvW3zgASUoDtVUukNK+REC/7W0wJHgN4e2iC/8uioi1sYRE3nLl7k4kH9Kzo6 Fc9e2tc84tqLA7SepqvxVVpW2Ib0U2tLuyIxt1dZmgpGLnZU2mlVzROPfW7lFO0Z6u7v gn9HQ/wbVkBwA83WD5YleoAiQr7YH5PB3Fvt9B+Lcy9oDu9kN+8JHzFnWXAyj/PUYSZx VxjtMsAdFJPBtNS7uz4+0wWbwFbddiF6FrkNrbeie/B/3bejZ7hDpSrLk4kBcFpaKkCb P/BRpY5Vh/rHh/2s6gmiFxNbgO8foWHgdUOqOEwDY9XwSldnldpY9fmY2T2i4jx4Su05 SENA== X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Hillf Danton , Sandeep Patil , Sudipto Paul , Vincent Donnefort , Chenbo Feng , Alistair Strachan , Liam Mark , "Andrew F. Davis" , Christoph Hellwig , dri-devel@lists.freedesktop.org, Hridya Valsaraju , Pratik Patel MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: "Andrew F. Davis" This framework allows a unified userspace interface for dma-buf exporters, allowing userland to allocate specific types of memory for use in dma-buf sharing. Each heap is given its own device node, which a user can allocate a dma-buf fd from using the DMA_HEAP_IOC_ALLOC. This code is an evoluiton of the Android ION implementation, and a big thanks is due to its authors/maintainers over time for their effort: Rebecca Schultz Zavin, Colin Cross, Benjamin Gaignard, Laura Abbott, and many other contributors! Cc: Laura Abbott Cc: Benjamin Gaignard Cc: Sumit Semwal Cc: Liam Mark Cc: Pratik Patel Cc: Brian Starkey Cc: Vincent Donnefort Cc: Sudipto Paul Cc: Andrew F. Davis Cc: Christoph Hellwig Cc: Chenbo Feng Cc: Alistair Strachan Cc: Hridya Valsaraju Cc: Sandeep Patil Cc: Hillf Danton Cc: Dave Airlie Cc: dri-devel@lists.freedesktop.org Reviewed-by: Brian Starkey Acked-by: Sandeep Patil Signed-off-by: Andrew F. Davis Signed-off-by: John Stultz --- v2: * Folded down fixes I had previously shared in implementing heaps * Make flags a u64 (Suggested by Laura) * Add PAGE_ALIGN() fix to the core alloc funciton * IOCTL fixups suggested by Brian * Added fixes suggested by Benjamin * Removed core stats mgmt, as that should be implemented by per-heap code * Changed alloc to return a dma-buf fd, rather than a buffer (as it simplifies error handling) v3: * Removed scare-quotes in MAINTAINERS email address * Get rid of .release function as it didn't do anything (from Christoph) * Renamed filp to file (suggested by Christoph) * Split out ioctl handling to separate function (suggested by Christoph) * Add comment documenting PAGE_ALIGN usage (suggested by Brian) * Switch from idr to Xarray (suggested by Brian) * Fixup cdev creation (suggested by Brian) * Avoid EXPORT_SYMBOL until we finalize modules (suggested by Brian) * Make struct dma_heap internal only (folded in from Andrew) * Small cleanups suggested by GregKH * Provide class->devnode callback to get consistent /dev/ subdirectory naming (Suggested by Bjorn) v4: * Folded down dma-heap.h change that was in a following patch * Added fd_flags entry to allocation structure and pass it through to heap code for use on dma-buf fd creation (suggested by Benjamin) v5: * Minor cleanups v6: * Improved error path handling, minor whitespace fixes, both suggested by Brian v7: * Longer Kconfig description to quiet checkpatch warnings * Re-add compat_ioctl bits (Hridya noticed 32bit userland wasn't working) v8: * Make struct dma_heap_ops consts (Suggested by Christoph) * Checkpatch whitespace fixups v9: * Minor cleanups suggested by Brian Starkey * Rename dma_heap_get_data->dma_heap_get_drvdata suggested by Hilf Danton v11: * Kconfig text improvements suggested by Randy Dunlap v12: * Add logic to prevent duplicately named heaps being added * Add symbol exports for heaps as modules v13: * Re-remove symbol exports per discussion w/ Brian. Will resubmit in a separte patch for review v14: * Reworked ioctl handler to zero fill any difference in structure size, similar to what the DRM core does, as suggested by Dave Airlie * Removed now unnecessary reserved bits in allocate_data * Added get_features ioctl as suggested by Dave Airlie * Removed pr_warn_once messages as requested by Dave Airlie v15: * Dropped the get_features ioctl as suggested by Brian Starkey and Daniel Vetter * Add listhead comment suggested by Sandeep Patil * Dropped minor value in struct dma_heap as suggested by Sandeep Patil * Fix grammar typo from Brian Starkey v16: * Typo fix suggested by Hridya Valsaraju --- MAINTAINERS | 18 +++ drivers/dma-buf/Kconfig | 9 ++ drivers/dma-buf/Makefile | 1 + drivers/dma-buf/dma-heap.c | 297 ++++++++++++++++++++++++++++++++++ include/linux/dma-heap.h | 59 +++++++ include/uapi/linux/dma-heap.h | 53 ++++++ 6 files changed, 437 insertions(+) create mode 100644 drivers/dma-buf/dma-heap.c create mode 100644 include/linux/dma-heap.h create mode 100644 include/uapi/linux/dma-heap.h diff --git a/MAINTAINERS b/MAINTAINERS index cba1095547fd..568f94172905 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -4940,6 +4940,24 @@ F: include/linux/*fence.h F: Documentation/driver-api/dma-buf.rst T: git git://anongit.freedesktop.org/drm/drm-misc +DMA-BUF HEAPS FRAMEWORK +M: Sumit Semwal +R: Andrew F. Davis +R: Benjamin Gaignard +R: Liam Mark +R: Laura Abbott +R: Brian Starkey +R: John Stultz +S: Maintained +L: linux-media@vger.kernel.org +L: dri-devel@lists.freedesktop.org +L: linaro-mm-sig@lists.linaro.org (moderated for non-subscribers) +F: include/uapi/linux/dma-heap.h +F: include/linux/dma-heap.h +F: drivers/dma-buf/dma-heap.c +F: drivers/dma-buf/heaps/* +T: git git://anongit.freedesktop.org/drm/drm-misc + DMA GENERIC OFFLOAD ENGINE SUBSYSTEM M: Vinod Koul L: dmaengine@vger.kernel.org diff --git a/drivers/dma-buf/Kconfig b/drivers/dma-buf/Kconfig index a23b6752d11a..bffa58fc3e6e 100644 --- a/drivers/dma-buf/Kconfig +++ b/drivers/dma-buf/Kconfig @@ -44,4 +44,13 @@ config DMABUF_SELFTESTS default n depends on DMA_SHARED_BUFFER +menuconfig DMABUF_HEAPS + bool "DMA-BUF Userland Memory Heaps" + select DMA_SHARED_BUFFER + help + Choose this option to enable the DMA-BUF userland memory heaps. + This options creates per heap chardevs in /dev/dma_heap/ which + allows userspace to allocate dma-bufs that can be shared + between drivers. + endmenu diff --git a/drivers/dma-buf/Makefile b/drivers/dma-buf/Makefile index 03479da06422..caee5eb3d351 100644 --- a/drivers/dma-buf/Makefile +++ b/drivers/dma-buf/Makefile @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0-only obj-y := dma-buf.o dma-fence.o dma-fence-array.o dma-fence-chain.o \ dma-resv.o seqno-fence.o +obj-$(CONFIG_DMABUF_HEAPS) += dma-heap.o obj-$(CONFIG_SYNC_FILE) += sync_file.o obj-$(CONFIG_SW_SYNC) += sw_sync.o sync_debug.o obj-$(CONFIG_UDMABUF) += udmabuf.o diff --git a/drivers/dma-buf/dma-heap.c b/drivers/dma-buf/dma-heap.c new file mode 100644 index 000000000000..4f04d104ae61 --- /dev/null +++ b/drivers/dma-buf/dma-heap.c @@ -0,0 +1,297 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Framework for userspace DMA-BUF allocations + * + * Copyright (C) 2011 Google, Inc. + * Copyright (C) 2019 Linaro Ltd. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define DEVNAME "dma_heap" + +#define NUM_HEAP_MINORS 128 + +/** + * struct dma_heap - represents a dmabuf heap in the system + * @name: used for debugging/device-node name + * @ops: ops struct for this heap + * @heap_devt heap device node + * @list list head connecting to list of heaps + * @heap_cdev heap char device + * + * Represents a heap of memory from which buffers can be made. + */ +struct dma_heap { + const char *name; + const struct dma_heap_ops *ops; + void *priv; + dev_t heap_devt; + struct list_head list; + struct cdev heap_cdev; +}; + +static LIST_HEAD(heap_list); +static DEFINE_MUTEX(heap_list_lock); +static dev_t dma_heap_devt; +static struct class *dma_heap_class; +static DEFINE_XARRAY_ALLOC(dma_heap_minors); + +static int dma_heap_buffer_alloc(struct dma_heap *heap, size_t len, + unsigned int fd_flags, + unsigned int heap_flags) +{ + /* + * Allocations from all heaps have to begin + * and end on page boundaries. + */ + len = PAGE_ALIGN(len); + if (!len) + return -EINVAL; + + return heap->ops->allocate(heap, len, fd_flags, heap_flags); +} + +static int dma_heap_open(struct inode *inode, struct file *file) +{ + struct dma_heap *heap; + + heap = xa_load(&dma_heap_minors, iminor(inode)); + if (!heap) { + pr_err("dma_heap: minor %d unknown.\n", iminor(inode)); + return -ENODEV; + } + + /* instance data as context */ + file->private_data = heap; + nonseekable_open(inode, file); + + return 0; +} + +static long dma_heap_ioctl_allocate(struct file *file, void *data) +{ + struct dma_heap_allocation_data *heap_allocation = data; + struct dma_heap *heap = file->private_data; + int fd; + + if (heap_allocation->fd) + return -EINVAL; + + if (heap_allocation->fd_flags & ~DMA_HEAP_VALID_FD_FLAGS) + return -EINVAL; + + if (heap_allocation->heap_flags & ~DMA_HEAP_VALID_HEAP_FLAGS) + return -EINVAL; + + fd = dma_heap_buffer_alloc(heap, heap_allocation->len, + heap_allocation->fd_flags, + heap_allocation->heap_flags); + if (fd < 0) + return fd; + + heap_allocation->fd = fd; + + return 0; +} + +unsigned int dma_heap_ioctl_cmds[] = { + DMA_HEAP_IOC_ALLOC, +}; + +static long dma_heap_ioctl(struct file *file, unsigned int ucmd, + unsigned long arg) +{ + char stack_kdata[128]; + char *kdata = stack_kdata; + unsigned int kcmd; + unsigned int in_size, out_size, drv_size, ksize; + int nr = _IOC_NR(ucmd); + int ret = 0; + + if (nr >= ARRAY_SIZE(dma_heap_ioctl_cmds)) + return -EINVAL; + + /* Get the kernel ioctl cmd that matches */ + kcmd = dma_heap_ioctl_cmds[nr]; + + /* Figure out the delta between user cmd size and kernel cmd size */ + drv_size = _IOC_SIZE(kcmd); + out_size = _IOC_SIZE(ucmd); + in_size = out_size; + if ((ucmd & kcmd & IOC_IN) == 0) + in_size = 0; + if ((ucmd & kcmd & IOC_OUT) == 0) + out_size = 0; + ksize = max(max(in_size, out_size), drv_size); + + /* If necessary, allocate buffer for ioctl argument */ + if (ksize > sizeof(stack_kdata)) { + kdata = kmalloc(ksize, GFP_KERNEL); + if (!kdata) + return -ENOMEM; + } + + if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) { + ret = -EFAULT; + goto err; + } + + /* zero out any difference between the kernel/user structure size */ + if (ksize > in_size) + memset(kdata + in_size, 0, ksize - in_size); + + switch (kcmd) { + case DMA_HEAP_IOC_ALLOC: + ret = dma_heap_ioctl_allocate(file, kdata); + break; + default: + return -ENOTTY; + } + + if (copy_to_user((void __user *)arg, kdata, out_size) != 0) + ret = -EFAULT; +err: + if (kdata != stack_kdata) + kfree(kdata); + return ret; +} + +static const struct file_operations dma_heap_fops = { + .owner = THIS_MODULE, + .open = dma_heap_open, + .unlocked_ioctl = dma_heap_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = dma_heap_ioctl, +#endif +}; + +/** + * dma_heap_get_drvdata() - get per-subdriver data for the heap + * @heap: DMA-Heap to retrieve private data for + * + * Returns: + * The per-subdriver data for the heap. + */ +void *dma_heap_get_drvdata(struct dma_heap *heap) +{ + return heap->priv; +} + +struct dma_heap *dma_heap_add(const struct dma_heap_export_info *exp_info) +{ + struct dma_heap *heap, *h, *err_ret; + struct device *dev_ret; + unsigned int minor; + int ret; + + if (!exp_info->name || !strcmp(exp_info->name, "")) { + pr_err("dma_heap: Cannot add heap without a name\n"); + return ERR_PTR(-EINVAL); + } + + if (!exp_info->ops || !exp_info->ops->allocate) { + pr_err("dma_heap: Cannot add heap with invalid ops struct\n"); + return ERR_PTR(-EINVAL); + } + + /* check the name is unique */ + mutex_lock(&heap_list_lock); + list_for_each_entry(h, &heap_list, list) { + if (!strcmp(h->name, exp_info->name)) { + mutex_unlock(&heap_list_lock); + pr_err("dma_heap: Already registered heap named %s\n", + exp_info->name); + return ERR_PTR(-EINVAL); + } + } + mutex_unlock(&heap_list_lock); + + heap = kzalloc(sizeof(*heap), GFP_KERNEL); + if (!heap) + return ERR_PTR(-ENOMEM); + + heap->name = exp_info->name; + heap->ops = exp_info->ops; + heap->priv = exp_info->priv; + + /* Find unused minor number */ + ret = xa_alloc(&dma_heap_minors, &minor, heap, + XA_LIMIT(0, NUM_HEAP_MINORS - 1), GFP_KERNEL); + if (ret < 0) { + pr_err("dma_heap: Unable to get minor number for heap\n"); + err_ret = ERR_PTR(ret); + goto err0; + } + + /* Create device */ + heap->heap_devt = MKDEV(MAJOR(dma_heap_devt), minor); + + cdev_init(&heap->heap_cdev, &dma_heap_fops); + ret = cdev_add(&heap->heap_cdev, heap->heap_devt, 1); + if (ret < 0) { + pr_err("dma_heap: Unable to add char device\n"); + err_ret = ERR_PTR(ret); + goto err1; + } + + dev_ret = device_create(dma_heap_class, + NULL, + heap->heap_devt, + NULL, + heap->name); + if (IS_ERR(dev_ret)) { + pr_err("dma_heap: Unable to create device\n"); + err_ret = ERR_CAST(dev_ret); + goto err2; + } + /* Add heap to the list */ + mutex_lock(&heap_list_lock); + list_add(&heap->list, &heap_list); + mutex_unlock(&heap_list_lock); + + return heap; + +err2: + cdev_del(&heap->heap_cdev); +err1: + xa_erase(&dma_heap_minors, minor); +err0: + kfree(heap); + return err_ret; +} + +static char *dma_heap_devnode(struct device *dev, umode_t *mode) +{ + return kasprintf(GFP_KERNEL, "dma_heap/%s", dev_name(dev)); +} + +static int dma_heap_init(void) +{ + int ret; + + ret = alloc_chrdev_region(&dma_heap_devt, 0, NUM_HEAP_MINORS, DEVNAME); + if (ret) + return ret; + + dma_heap_class = class_create(THIS_MODULE, DEVNAME); + if (IS_ERR(dma_heap_class)) { + unregister_chrdev_region(dma_heap_devt, NUM_HEAP_MINORS); + return PTR_ERR(dma_heap_class); + } + dma_heap_class->devnode = dma_heap_devnode; + + return 0; +} +subsys_initcall(dma_heap_init); diff --git a/include/linux/dma-heap.h b/include/linux/dma-heap.h new file mode 100644 index 000000000000..454e354d1ffb --- /dev/null +++ b/include/linux/dma-heap.h @@ -0,0 +1,59 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * DMABUF Heaps Allocation Infrastructure + * + * Copyright (C) 2011 Google, Inc. + * Copyright (C) 2019 Linaro Ltd. + */ + +#ifndef _DMA_HEAPS_H +#define _DMA_HEAPS_H + +#include +#include + +struct dma_heap; + +/** + * struct dma_heap_ops - ops to operate on a given heap + * @allocate: allocate dmabuf and return fd + * + * allocate returns dmabuf fd on success, -errno on error. + */ +struct dma_heap_ops { + int (*allocate)(struct dma_heap *heap, + unsigned long len, + unsigned long fd_flags, + unsigned long heap_flags); +}; + +/** + * struct dma_heap_export_info - information needed to export a new dmabuf heap + * @name: used for debugging/device-node name + * @ops: ops struct for this heap + * @priv: heap exporter private data + * + * Information needed to export a new dmabuf heap. + */ +struct dma_heap_export_info { + const char *name; + const struct dma_heap_ops *ops; + void *priv; +}; + +/** + * dma_heap_get_drvdata() - get per-heap driver data + * @heap: DMA-Heap to retrieve private data for + * + * Returns: + * The per-heap data for the heap. + */ +void *dma_heap_get_drvdata(struct dma_heap *heap); + +/** + * dma_heap_add - adds a heap to dmabuf heaps + * @exp_info: information needed to register this heap + */ +struct dma_heap *dma_heap_add(const struct dma_heap_export_info *exp_info); + +#endif /* _DMA_HEAPS_H */ diff --git a/include/uapi/linux/dma-heap.h b/include/uapi/linux/dma-heap.h new file mode 100644 index 000000000000..73e7f66c1cae --- /dev/null +++ b/include/uapi/linux/dma-heap.h @@ -0,0 +1,53 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* + * DMABUF Heaps Userspace API + * + * Copyright (C) 2011 Google, Inc. + * Copyright (C) 2019 Linaro Ltd. + */ +#ifndef _UAPI_LINUX_DMABUF_POOL_H +#define _UAPI_LINUX_DMABUF_POOL_H + +#include +#include + +/** + * DOC: DMABUF Heaps Userspace API + */ + +/* Valid FD_FLAGS are O_CLOEXEC, O_RDONLY, O_WRONLY, O_RDWR */ +#define DMA_HEAP_VALID_FD_FLAGS (O_CLOEXEC | O_ACCMODE) + +/* Currently no heap flags */ +#define DMA_HEAP_VALID_HEAP_FLAGS (0) + +/** + * struct dma_heap_allocation_data - metadata passed from userspace for + * allocations + * @len: size of the allocation + * @fd: will be populated with a fd which provides the + * handle to the allocated dma-buf + * @fd_flags: file descriptor flags used when allocating + * @heap_flags: flags passed to heap + * + * Provided by userspace as an argument to the ioctl + */ +struct dma_heap_allocation_data { + __u64 len; + __u32 fd; + __u32 fd_flags; + __u64 heap_flags; +}; + +#define DMA_HEAP_IOC_MAGIC 'H' + +/** + * DOC: DMA_HEAP_IOC_ALLOC - allocate memory from pool + * + * Takes a dma_heap_allocation_data struct and returns it with the fd field + * populated with the dmabuf handle of the allocation. + */ +#define DMA_HEAP_IOC_ALLOC _IOWR(DMA_HEAP_IOC_MAGIC, 0x0,\ + struct dma_heap_allocation_data) + +#endif /* _UAPI_LINUX_DMABUF_POOL_H */