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diff --git a/src/libcamera/dma_heaps.cpp b/src/libcamera/dma_heaps.cpp
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+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2020, Raspberry Pi Ltd
+ *
+ * dma_heaps.cpp - Helper class for dma-heap allocations.
+ */
+
+#include "libcamera/internal/dma_heaps.h"
+
+#include <array>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+
+#include <linux/dma-buf.h>
+#include <linux/dma-heap.h>
+
+#include <libcamera/base/log.h>
+
+/**
+ * \file dma_heaps.cpp
+ * \brief dma-heap allocator
+ */
+
+namespace libcamera {
+
+/*
+ * /dev/dma_heap/linux,cma is the dma-heap allocator, which allows dmaheap-cma
+ * to only have to worry about importing.
+ *
+ * Annoyingly, should the cma heap size be specified on the kernel command line
+ * instead of DT, the heap gets named "reserved" instead.
+ */
+
+#ifndef __DOXYGEN__
+struct DmaHeapInfo {
+	DmaHeap::DmaHeapFlag type;
+	const char *deviceNodeName;
+};
+#endif
+
+static constexpr std::array<DmaHeapInfo, 3> heapInfos = { {
+	{ DmaHeap::DmaHeapFlag::Cma, "/dev/dma_heap/linux,cma" },
+	{ DmaHeap::DmaHeapFlag::Cma, "/dev/dma_heap/reserved" },
+	{ DmaHeap::DmaHeapFlag::System, "/dev/dma_heap/system" },
+} };
+
+LOG_DEFINE_CATEGORY(DmaHeap)
+
+/**
+ * \class DmaHeap
+ * \brief Helper class for dma-heap allocations
+ *
+ * DMA heaps are kernel devices that provide an API to allocate memory from
+ * different pools called "heaps", wrap each allocated piece of memory in a
+ * dmabuf object, and return the dmabuf file descriptor to userspace. Multiple
+ * heaps can be provided by the system, with different properties for the
+ * underlying memory.
+ *
+ * This class wraps a DMA heap selected at construction time, and exposes
+ * functions to manage memory allocation.
+ */
+
+/**
+ * \enum DmaHeap::DmaHeapFlag
+ * \brief Type of the dma-heap
+ * \var DmaHeap::Cma
+ * \brief Allocate from a CMA dma-heap, providing physically-contiguous memory
+ * \var DmaHeap::System
+ * \brief Allocate from the system dma-heap, using the page allocator
+ */
+
+/**
+ * \typedef DmaHeap::DmaHeapFlags
+ * \brief A bitwise combination of DmaHeap::DmaHeapFlag values
+ */
+
+/**
+ * \brief Construct a DmaHeap of a given type
+ * \param[in] type The type(s) of the dma-heap(s) to allocate from
+ *
+ * The DMA heap type is selected with the \a type parameter, which defaults to
+ * the CMA heap. If no heap of the given type can be accessed, the constructed
+ * DmaHeap instance is invalid as indicated by the isValid() function.
+ *
+ * Multiple types can be selected by combining type flags, in which case the
+ * constructed DmaHeap will match one of the types. If the system provides
+ * multiple heaps that match the requested types, which heap is used is
+ * undefined.
+ */
+DmaHeap::DmaHeap(DmaHeapFlags type)
+{
+	for (const auto &info : heapInfos) {
+		if (!(type & info.type))
+			continue;
+
+		int ret = ::open(info.deviceNodeName, O_RDWR | O_CLOEXEC, 0);
+		if (ret < 0) {
+			ret = errno;
+			LOG(DmaHeap, Debug)
+				<< "Failed to open " << info.deviceNodeName << ": "
+				<< strerror(ret);
+			continue;
+		}
+
+		LOG(DmaHeap, Debug) << "Using " << info.deviceNodeName;
+		dmaHeapHandle_ = UniqueFD(ret);
+		break;
+	}
+
+	if (!dmaHeapHandle_.isValid())
+		LOG(DmaHeap, Error) << "Could not open any dmaHeap device";
+}
+
+/**
+ * \brief Destroy the DmaHeap instance
+ */
+DmaHeap::~DmaHeap() = default;
+
+/**
+ * \fn DmaHeap::isValid()
+ * \brief Check if the DmaHeap instance is valid
+ * \return True if the DmaHeap is valid, false otherwise
+ */
+
+/**
+ * \brief Allocate a dma-buf from the DmaHeap
+ * \param [in] name The name to set for the allocated buffer
+ * \param [in] size The size of the buffer to allocate
+ *
+ * Allocates a dma-buf with read/write access.
+ *
+ * If the allocation fails, return an invalid UniqueFD.
+ *
+ * \return The UniqueFD of the allocated buffer
+ */
+UniqueFD DmaHeap::alloc(const char *name, std::size_t size)
+{
+	int ret;
+
+	if (!name)
+		return {};
+
+	struct dma_heap_allocation_data alloc = {};
+
+	alloc.len = size;
+	alloc.fd_flags = O_CLOEXEC | O_RDWR;
+
+	ret = ::ioctl(dmaHeapHandle_.get(), DMA_HEAP_IOCTL_ALLOC, &alloc);
+	if (ret < 0) {
+		LOG(DmaHeap, Error) << "dmaHeap allocation failure for " << name;
+		return {};
+	}
+
+	UniqueFD allocFd(alloc.fd);
+	ret = ::ioctl(allocFd.get(), DMA_BUF_SET_NAME, name);
+	if (ret < 0) {
+		LOG(DmaHeap, Error) << "dmaHeap naming failure for " << name;
+		return {};
+	}
+
+	return allocFd;
+}
+
+} /* namespace libcamera */