diff mbox series

[RFC,4/6,v3] dma-buf: heaps: Add CMA heap to dmabuf heapss

Message ID 1553818562-2516-5-git-send-email-john.stultz@linaro.org
State Superseded
Headers show
Series DMA-BUF Heaps (destaging ION) | expand

Commit Message

John Stultz March 29, 2019, 12:16 a.m. UTC
This adds a CMA heap, which allows userspace to allocate
a dma-buf of contiguous memory out of a CMA region.

This code is an evolution of the Android ION implementation, so
thanks to its original author and maintainters:
  Benjamin Gaignard, Laura Abbott, and others!

Cc: Laura Abbott <labbott@redhat.com>
Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Liam Mark <lmark@codeaurora.org>
Cc: Pratik Patel <pratikp@codeaurora.org>
Cc: Brian Starkey <Brian.Starkey@arm.com>
Cc: Vincent Donnefort <Vincent.Donnefort@arm.com>
Cc: Sudipto Paul <Sudipto.Paul@arm.com>
Cc: Andrew F. Davis <afd@ti.com>
Cc: Xu YiPing <xuyiping@hisilicon.com>
Cc: "Chenfeng (puck)" <puck.chen@hisilicon.com>
Cc: butao <butao@hisilicon.com>
Cc: "Xiaqing (A)" <saberlily.xia@hisilicon.com>
Cc: Yudongbin <yudongbin@hisilicon.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Chenbo Feng <fengc@google.com>
Cc: Alistair Strachan <astrachan@google.com>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: John Stultz <john.stultz@linaro.org>

---
v2:
* Switch allocate to return dmabuf fd
* Simplify init code
* Checkpatch fixups
v3:
* Switch to inline function for to_cma_heap()
* Minor cleanups suggested by Brian
* Fold in new registration style from Andrew
* Folded in changes from Andrew to use simplified page list
  from the heap helpers
---
 drivers/dma-buf/heaps/Kconfig    |   8 ++
 drivers/dma-buf/heaps/Makefile   |   1 +
 drivers/dma-buf/heaps/cma_heap.c | 170 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 179 insertions(+)
 create mode 100644 drivers/dma-buf/heaps/cma_heap.c

-- 
2.7.4

Comments

Benjamin Gaignard March 29, 2019, 2:44 p.m. UTC | #1
Le ven. 29 mars 2019 à 01:16, John Stultz <john.stultz@linaro.org> a écrit :
>

> This adds a CMA heap, which allows userspace to allocate

> a dma-buf of contiguous memory out of a CMA region.

>

> This code is an evolution of the Android ION implementation, so

> thanks to its original author and maintainters:

>   Benjamin Gaignard, Laura Abbott, and others!

>

> Cc: Laura Abbott <labbott@redhat.com>

> Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>

> Cc: Sumit Semwal <sumit.semwal@linaro.org>

> Cc: Liam Mark <lmark@codeaurora.org>

> Cc: Pratik Patel <pratikp@codeaurora.org>

> Cc: Brian Starkey <Brian.Starkey@arm.com>

> Cc: Vincent Donnefort <Vincent.Donnefort@arm.com>

> Cc: Sudipto Paul <Sudipto.Paul@arm.com>

> Cc: Andrew F. Davis <afd@ti.com>

> Cc: Xu YiPing <xuyiping@hisilicon.com>

> Cc: "Chenfeng (puck)" <puck.chen@hisilicon.com>

> Cc: butao <butao@hisilicon.com>

> Cc: "Xiaqing (A)" <saberlily.xia@hisilicon.com>

> Cc: Yudongbin <yudongbin@hisilicon.com>

> Cc: Christoph Hellwig <hch@infradead.org>

> Cc: Chenbo Feng <fengc@google.com>

> Cc: Alistair Strachan <astrachan@google.com>

> Cc: dri-devel@lists.freedesktop.org

> Signed-off-by: John Stultz <john.stultz@linaro.org>

> ---

> v2:

> * Switch allocate to return dmabuf fd

> * Simplify init code

> * Checkpatch fixups

> v3:

> * Switch to inline function for to_cma_heap()

> * Minor cleanups suggested by Brian

> * Fold in new registration style from Andrew

> * Folded in changes from Andrew to use simplified page list

>   from the heap helpers

> ---

>  drivers/dma-buf/heaps/Kconfig    |   8 ++

>  drivers/dma-buf/heaps/Makefile   |   1 +

>  drivers/dma-buf/heaps/cma_heap.c | 170 +++++++++++++++++++++++++++++++++++++++

>  3 files changed, 179 insertions(+)

>  create mode 100644 drivers/dma-buf/heaps/cma_heap.c

>

> diff --git a/drivers/dma-buf/heaps/Kconfig b/drivers/dma-buf/heaps/Kconfig

> index 2050527..a5eef06 100644

> --- a/drivers/dma-buf/heaps/Kconfig

> +++ b/drivers/dma-buf/heaps/Kconfig

> @@ -4,3 +4,11 @@ config DMABUF_HEAPS_SYSTEM

>         help

>           Choose this option to enable the system dmabuf heap. The system heap

>           is backed by pages from the buddy allocator. If in doubt, say Y.

> +

> +config DMABUF_HEAPS_CMA

> +       bool "DMA-BUF CMA Heap"

> +       depends on DMABUF_HEAPS && DMA_CMA

> +       help

> +         Choose this option to enable dma-buf CMA heap. This heap is backed

> +         by the Contiguous Memory Allocator (CMA). If your system has these

> +         regions, you should say Y here.

> diff --git a/drivers/dma-buf/heaps/Makefile b/drivers/dma-buf/heaps/Makefile

> index d1808ec..6e54cde 100644

> --- a/drivers/dma-buf/heaps/Makefile

> +++ b/drivers/dma-buf/heaps/Makefile

> @@ -1,3 +1,4 @@

>  # SPDX-License-Identifier: GPL-2.0

>  obj-y                                  += heap-helpers.o

>  obj-$(CONFIG_DMABUF_HEAPS_SYSTEM)      += system_heap.o

> +obj-$(CONFIG_DMABUF_HEAPS_CMA)         += cma_heap.o

> diff --git a/drivers/dma-buf/heaps/cma_heap.c b/drivers/dma-buf/heaps/cma_heap.c

> new file mode 100644

> index 0000000..f4485c60

> --- /dev/null

> +++ b/drivers/dma-buf/heaps/cma_heap.c

> @@ -0,0 +1,170 @@

> +// SPDX-License-Identifier: GPL-2.0

> +/*

> + * DMABUF CMA heap exporter

> + *

> + * Copyright (C) 2012, 2019 Linaro Ltd.

> + * Author: <benjamin.gaignard@linaro.org> for ST-Ericsson.

> + */

> +

> +#include <linux/device.h>

> +#include <linux/dma-buf.h>

> +#include <linux/dma-heap.h>

> +#include <linux/slab.h>

> +#include <linux/errno.h>

> +#include <linux/err.h>

> +#include <linux/cma.h>

> +#include <linux/scatterlist.h>

> +#include <linux/highmem.h>

> +

> +#include "heap-helpers.h"

> +

> +struct cma_heap {

> +       struct dma_heap *heap;

> +       struct cma *cma;

> +};

> +

> +static void cma_heap_free(struct heap_helper_buffer *buffer)

> +{

> +       struct cma_heap *cma_heap = dma_heap_get_data(buffer->heap_buffer.heap);

> +       struct page *pages = buffer->priv_virt;

> +       unsigned long nr_pages;

> +

> +       nr_pages = buffer->heap_buffer.size >> PAGE_SHIFT;

> +

> +       /* free page list */

> +       kfree(buffer->pages);

> +       /* release memory */

> +       cma_release(cma_heap->cma, pages, nr_pages);

> +       kfree(buffer);

> +}

> +

> +/* dmabuf heap CMA operations functions */

> +static int cma_heap_allocate(struct dma_heap *heap,

> +                               unsigned long len,

> +                               unsigned long flags)

> +{

> +       struct cma_heap *cma_heap = dma_heap_get_data(heap);

> +       struct heap_helper_buffer *helper_buffer;

> +       struct page *pages;

> +       size_t size = PAGE_ALIGN(len);

> +       unsigned long nr_pages = size >> PAGE_SHIFT;

> +       unsigned long align = get_order(size);

> +       DEFINE_DMA_BUF_EXPORT_INFO(exp_info);

> +       struct dma_buf *dmabuf;

> +       int ret = -ENOMEM;

> +       pgoff_t pg;

> +

> +       if (align > CONFIG_CMA_ALIGNMENT)

> +               align = CONFIG_CMA_ALIGNMENT;

> +

> +       helper_buffer = kzalloc(sizeof(*helper_buffer), GFP_KERNEL);

> +       if (!helper_buffer)

> +               return -ENOMEM;

> +

> +       INIT_HEAP_HELPER_BUFFER(helper_buffer, cma_heap_free);

> +       helper_buffer->heap_buffer.flags = flags;

> +       helper_buffer->heap_buffer.heap = heap;

> +       helper_buffer->heap_buffer.size = len;

> +

> +       pages = cma_alloc(cma_heap->cma, nr_pages, align, false);

> +       if (!pages)

> +               goto free_buf;

> +

> +       if (PageHighMem(pages)) {

> +               unsigned long nr_clear_pages = nr_pages;

> +               struct page *page = pages;

> +

> +               while (nr_clear_pages > 0) {

> +                       void *vaddr = kmap_atomic(page);

> +

> +                       memset(vaddr, 0, PAGE_SIZE);

> +                       kunmap_atomic(vaddr);

> +                       page++;

> +                       nr_clear_pages--;

> +               }

> +       } else {

> +               memset(page_address(pages), 0, size);

> +       }

> +

> +       helper_buffer->pagecount = nr_pages;

> +       helper_buffer->pages = kmalloc_array(helper_buffer->pagecount,

> +                                            sizeof(*helper_buffer->pages),

> +                                            GFP_KERNEL);

> +       if (!helper_buffer->pages) {

> +               ret = -ENOMEM;

> +               goto free_cma;

> +       }

> +

> +       for (pg = 0; pg < helper_buffer->pagecount; pg++) {

> +               helper_buffer->pages[pg] = &pages[pg];

> +               if (!helper_buffer->pages[pg])

> +                       goto free_pages;

> +       }

> +

> +       /* create the dmabuf */

> +       exp_info.ops = &heap_helper_ops;

> +       exp_info.size = len;

> +       exp_info.flags = O_RDWR;


I think that the flags should be provided when requesting the allocation
like it is done in DRM or V4L2.
For me DMA_HEAP_VALID_FLAGS = (O_CLOEXEC | O_ACCMODE).

Benjamin

Benjamin

> +       exp_info.priv = &helper_buffer->heap_buffer;

> +       dmabuf = dma_buf_export(&exp_info);

> +       if (IS_ERR(dmabuf)) {

> +               ret = PTR_ERR(dmabuf);

> +               goto free_pages;

> +       }

> +

> +       helper_buffer->heap_buffer.dmabuf = dmabuf;

> +       helper_buffer->priv_virt = pages;

> +

> +       ret = dma_buf_fd(dmabuf, O_CLOEXEC);

> +       if (ret < 0) {

> +               dma_buf_put(dmabuf);

> +               /* just return, as put will call release and that will free */

> +               return ret;

> +       }

> +

> +       return ret;

> +

> +free_pages:

> +       kfree(helper_buffer->pages);

> +free_cma:

> +       cma_release(cma_heap->cma, pages, nr_pages);

> +free_buf:

> +       kfree(helper_buffer);

> +       return ret;

> +}

> +

> +static struct dma_heap_ops cma_heap_ops = {

> +       .allocate = cma_heap_allocate,

> +};

> +

> +static int __add_cma_heap(struct cma *cma, void *data)

> +{

> +       struct cma_heap *cma_heap;

> +       struct dma_heap_export_info exp_info;

> +

> +       cma_heap = kzalloc(sizeof(*cma_heap), GFP_KERNEL);

> +       if (!cma_heap)

> +               return -ENOMEM;

> +       cma_heap->cma = cma;

> +

> +       exp_info.name = cma_get_name(cma);

> +       exp_info.ops = &cma_heap_ops;

> +       exp_info.priv = cma_heap;

> +

> +       cma_heap->heap = dma_heap_add(&exp_info);

> +       if (IS_ERR(cma_heap->heap)) {

> +               int ret = PTR_ERR(cma_heap->heap);

> +

> +               kfree(cma_heap);

> +               return ret;

> +       }

> +

> +       return 0;

> +}

> +

> +static int add_cma_heaps(void)

> +{

> +       cma_for_each_area(__add_cma_heap, NULL);

> +       return 0;

> +}

> +device_initcall(add_cma_heaps);

> --

> 2.7.4

>
diff mbox series

Patch

diff --git a/drivers/dma-buf/heaps/Kconfig b/drivers/dma-buf/heaps/Kconfig
index 2050527..a5eef06 100644
--- a/drivers/dma-buf/heaps/Kconfig
+++ b/drivers/dma-buf/heaps/Kconfig
@@ -4,3 +4,11 @@  config DMABUF_HEAPS_SYSTEM
 	help
 	  Choose this option to enable the system dmabuf heap. The system heap
 	  is backed by pages from the buddy allocator. If in doubt, say Y.
+
+config DMABUF_HEAPS_CMA
+	bool "DMA-BUF CMA Heap"
+	depends on DMABUF_HEAPS && DMA_CMA
+	help
+	  Choose this option to enable dma-buf CMA heap. This heap is backed
+	  by the Contiguous Memory Allocator (CMA). If your system has these
+	  regions, you should say Y here.
diff --git a/drivers/dma-buf/heaps/Makefile b/drivers/dma-buf/heaps/Makefile
index d1808ec..6e54cde 100644
--- a/drivers/dma-buf/heaps/Makefile
+++ b/drivers/dma-buf/heaps/Makefile
@@ -1,3 +1,4 @@ 
 # SPDX-License-Identifier: GPL-2.0
 obj-y					+= heap-helpers.o
 obj-$(CONFIG_DMABUF_HEAPS_SYSTEM)	+= system_heap.o
+obj-$(CONFIG_DMABUF_HEAPS_CMA)		+= cma_heap.o
diff --git a/drivers/dma-buf/heaps/cma_heap.c b/drivers/dma-buf/heaps/cma_heap.c
new file mode 100644
index 0000000..f4485c60
--- /dev/null
+++ b/drivers/dma-buf/heaps/cma_heap.c
@@ -0,0 +1,170 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * DMABUF CMA heap exporter
+ *
+ * Copyright (C) 2012, 2019 Linaro Ltd.
+ * Author: <benjamin.gaignard@linaro.org> for ST-Ericsson.
+ */
+
+#include <linux/device.h>
+#include <linux/dma-buf.h>
+#include <linux/dma-heap.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/cma.h>
+#include <linux/scatterlist.h>
+#include <linux/highmem.h>
+
+#include "heap-helpers.h"
+
+struct cma_heap {
+	struct dma_heap *heap;
+	struct cma *cma;
+};
+
+static void cma_heap_free(struct heap_helper_buffer *buffer)
+{
+	struct cma_heap *cma_heap = dma_heap_get_data(buffer->heap_buffer.heap);
+	struct page *pages = buffer->priv_virt;
+	unsigned long nr_pages;
+
+	nr_pages = buffer->heap_buffer.size >> PAGE_SHIFT;
+
+	/* free page list */
+	kfree(buffer->pages);
+	/* release memory */
+	cma_release(cma_heap->cma, pages, nr_pages);
+	kfree(buffer);
+}
+
+/* dmabuf heap CMA operations functions */
+static int cma_heap_allocate(struct dma_heap *heap,
+				unsigned long len,
+				unsigned long flags)
+{
+	struct cma_heap *cma_heap = dma_heap_get_data(heap);
+	struct heap_helper_buffer *helper_buffer;
+	struct page *pages;
+	size_t size = PAGE_ALIGN(len);
+	unsigned long nr_pages = size >> PAGE_SHIFT;
+	unsigned long align = get_order(size);
+	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+	struct dma_buf *dmabuf;
+	int ret = -ENOMEM;
+	pgoff_t pg;
+
+	if (align > CONFIG_CMA_ALIGNMENT)
+		align = CONFIG_CMA_ALIGNMENT;
+
+	helper_buffer = kzalloc(sizeof(*helper_buffer), GFP_KERNEL);
+	if (!helper_buffer)
+		return -ENOMEM;
+
+	INIT_HEAP_HELPER_BUFFER(helper_buffer, cma_heap_free);
+	helper_buffer->heap_buffer.flags = flags;
+	helper_buffer->heap_buffer.heap = heap;
+	helper_buffer->heap_buffer.size = len;
+
+	pages = cma_alloc(cma_heap->cma, nr_pages, align, false);
+	if (!pages)
+		goto free_buf;
+
+	if (PageHighMem(pages)) {
+		unsigned long nr_clear_pages = nr_pages;
+		struct page *page = pages;
+
+		while (nr_clear_pages > 0) {
+			void *vaddr = kmap_atomic(page);
+
+			memset(vaddr, 0, PAGE_SIZE);
+			kunmap_atomic(vaddr);
+			page++;
+			nr_clear_pages--;
+		}
+	} else {
+		memset(page_address(pages), 0, size);
+	}
+
+	helper_buffer->pagecount = nr_pages;
+	helper_buffer->pages = kmalloc_array(helper_buffer->pagecount,
+					     sizeof(*helper_buffer->pages),
+					     GFP_KERNEL);
+	if (!helper_buffer->pages) {
+		ret = -ENOMEM;
+		goto free_cma;
+	}
+
+	for (pg = 0; pg < helper_buffer->pagecount; pg++) {
+		helper_buffer->pages[pg] = &pages[pg];
+		if (!helper_buffer->pages[pg])
+			goto free_pages;
+	}
+
+	/* create the dmabuf */
+	exp_info.ops = &heap_helper_ops;
+	exp_info.size = len;
+	exp_info.flags = O_RDWR;
+	exp_info.priv = &helper_buffer->heap_buffer;
+	dmabuf = dma_buf_export(&exp_info);
+	if (IS_ERR(dmabuf)) {
+		ret = PTR_ERR(dmabuf);
+		goto free_pages;
+	}
+
+	helper_buffer->heap_buffer.dmabuf = dmabuf;
+	helper_buffer->priv_virt = pages;
+
+	ret = dma_buf_fd(dmabuf, O_CLOEXEC);
+	if (ret < 0) {
+		dma_buf_put(dmabuf);
+		/* just return, as put will call release and that will free */
+		return ret;
+	}
+
+	return ret;
+
+free_pages:
+	kfree(helper_buffer->pages);
+free_cma:
+	cma_release(cma_heap->cma, pages, nr_pages);
+free_buf:
+	kfree(helper_buffer);
+	return ret;
+}
+
+static struct dma_heap_ops cma_heap_ops = {
+	.allocate = cma_heap_allocate,
+};
+
+static int __add_cma_heap(struct cma *cma, void *data)
+{
+	struct cma_heap *cma_heap;
+	struct dma_heap_export_info exp_info;
+
+	cma_heap = kzalloc(sizeof(*cma_heap), GFP_KERNEL);
+	if (!cma_heap)
+		return -ENOMEM;
+	cma_heap->cma = cma;
+
+	exp_info.name = cma_get_name(cma);
+	exp_info.ops = &cma_heap_ops;
+	exp_info.priv = cma_heap;
+
+	cma_heap->heap = dma_heap_add(&exp_info);
+	if (IS_ERR(cma_heap->heap)) {
+		int ret = PTR_ERR(cma_heap->heap);
+
+		kfree(cma_heap);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int add_cma_heaps(void)
+{
+	cma_for_each_area(__add_cma_heap, NULL);
+	return 0;
+}
+device_initcall(add_cma_heaps);