Commit a5d2d29e authored by John Stultz's avatar John Stultz Committed by Sumit Semwal
Browse files

dma-buf: heaps: Move heap-helper logic into the cma_heap implementation 



Since the heap-helpers logic ended up not being as generic as
hoped, move the heap-helpers dma_buf_ops implementations into
the cma_heap directly.

This will allow us to remove the heap_helpers code in a following
patch.

Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Liam Mark <lmark@codeaurora.org>
Cc: Laura Abbott <labbott@kernel.org>
Cc: Brian Starkey <Brian.Starkey@arm.com>
Cc: Hridya Valsaraju <hridya@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sandeep Patil <sspatil@google.com>
Cc: Daniel Mentz <danielmentz@google.com>
Cc: Chris Goldsworthy <cgoldswo@codeaurora.org>
Cc: Ørjan Eide <orjan.eide@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Ezequiel Garcia <ezequiel@collabora.com>
Cc: Simon Ser <contact@emersion.fr>
Cc: James Jones <jajones@nvidia.com>
Cc: linux-media@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: default avatarBrian Starkey <brian.starkey@arm.com>
Signed-off-by: default avatarJohn Stultz <john.stultz@linaro.org>
Signed-off-by: default avatarSumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201121235002.69945-3-john.stultz@linaro.org
parent 38129575

drivers/dma-buf/heaps/cma_heap.c

+270 −49
Original line number Diff line number Diff line
@@ -2,76 +2,295 @@ 
/*

 * DMABUF CMA heap exporter

 *

 * Copyright (C) 2012, 2019 Linaro Ltd.

 * Copyright (C) 2012, 2019, 2020 Linaro Ltd.

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

 *

 * Also utilizing parts of Andrew Davis' SRAM heap:

 * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/

 *	Andrew F. Davis <afd@ti.com>

 */



#include <linux/cma.h>

#include <linux/device.h>

#include <linux/dma-buf.h>

#include <linux/dma-heap.h>

#include <linux/dma-map-ops.h>

#include <linux/err.h>

#include <linux/errno.h>

#include <linux/highmem.h>

#include <linux/io.h>

#include <linux/mm.h>

#include <linux/module.h>

#include <linux/slab.h>

#include <linux/scatterlist.h>

#include <linux/sched/signal.h>

#include <linux/slab.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_buffer {

	struct cma_heap *heap;

	struct list_head attachments;

	struct mutex lock;

	unsigned long len;

	struct page *cma_pages;

	struct page **pages;

	pgoff_t pagecount;

	int vmap_cnt;

	void *vaddr;

};



struct dma_heap_attachment {

	struct device *dev;

	struct sg_table table;

	struct list_head list;

};



static int cma_heap_attach(struct dma_buf *dmabuf,

			   struct dma_buf_attachment *attachment)

{

	struct cma_heap *cma_heap = dma_heap_get_drvdata(buffer->heap);

	unsigned long nr_pages = buffer->pagecount;

	struct page *cma_pages = buffer->priv_virt;

	struct cma_heap_buffer *buffer = dmabuf->priv;

	struct dma_heap_attachment *a;

	int ret;



	/* free page list */

	kfree(buffer->pages);

	/* release memory */

	cma_release(cma_heap->cma, cma_pages, nr_pages);

	a = kzalloc(sizeof(*a), GFP_KERNEL);

	if (!a)

		return -ENOMEM;



	ret = sg_alloc_table_from_pages(&a->table, buffer->pages,

					buffer->pagecount, 0,

					buffer->pagecount << PAGE_SHIFT,

					GFP_KERNEL);

	if (ret) {

		kfree(a);

		return ret;

	}



	a->dev = attachment->dev;

	INIT_LIST_HEAD(&a->list);



	attachment->priv = a;



	mutex_lock(&buffer->lock);

	list_add(&a->list, &buffer->attachments);

	mutex_unlock(&buffer->lock);



	return 0;

}



static void cma_heap_detach(struct dma_buf *dmabuf,

			    struct dma_buf_attachment *attachment)

{

	struct cma_heap_buffer *buffer = dmabuf->priv;

	struct dma_heap_attachment *a = attachment->priv;



	mutex_lock(&buffer->lock);

	list_del(&a->list);

	mutex_unlock(&buffer->lock);



	sg_free_table(&a->table);

	kfree(a);

}



static struct sg_table *cma_heap_map_dma_buf(struct dma_buf_attachment *attachment,

					     enum dma_data_direction direction)

{

	struct dma_heap_attachment *a = attachment->priv;

	struct sg_table *table = &a->table;

	int ret;



	ret = dma_map_sgtable(attachment->dev, table, direction, 0);

	if (ret)

		return ERR_PTR(-ENOMEM);

	return table;

}



static void cma_heap_unmap_dma_buf(struct dma_buf_attachment *attachment,

				   struct sg_table *table,

				   enum dma_data_direction direction)

{

	dma_unmap_sgtable(attachment->dev, table, direction, 0);

}



static int cma_heap_dma_buf_begin_cpu_access(struct dma_buf *dmabuf,

					     enum dma_data_direction direction)

{

	struct cma_heap_buffer *buffer = dmabuf->priv;

	struct dma_heap_attachment *a;



	if (buffer->vmap_cnt)

		invalidate_kernel_vmap_range(buffer->vaddr, buffer->len);



	mutex_lock(&buffer->lock);

	list_for_each_entry(a, &buffer->attachments, list) {

		dma_sync_sgtable_for_cpu(a->dev, &a->table, direction);

	}

	mutex_unlock(&buffer->lock);



	return 0;

}



static int cma_heap_dma_buf_end_cpu_access(struct dma_buf *dmabuf,

					   enum dma_data_direction direction)

{

	struct cma_heap_buffer *buffer = dmabuf->priv;

	struct dma_heap_attachment *a;



	if (buffer->vmap_cnt)

		flush_kernel_vmap_range(buffer->vaddr, buffer->len);



	mutex_lock(&buffer->lock);

	list_for_each_entry(a, &buffer->attachments, list) {

		dma_sync_sgtable_for_device(a->dev, &a->table, direction);

	}

	mutex_unlock(&buffer->lock);



	return 0;

}



static vm_fault_t cma_heap_vm_fault(struct vm_fault *vmf)

{

	struct vm_area_struct *vma = vmf->vma;

	struct cma_heap_buffer *buffer = vma->vm_private_data;



	if (vmf->pgoff > buffer->pagecount)

		return VM_FAULT_SIGBUS;



	vmf->page = buffer->pages[vmf->pgoff];

	get_page(vmf->page);



	return 0;

}



static const struct vm_operations_struct dma_heap_vm_ops = {

	.fault = cma_heap_vm_fault,

};



static int cma_heap_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma)

{

	struct cma_heap_buffer *buffer = dmabuf->priv;



	if ((vma->vm_flags & (VM_SHARED | VM_MAYSHARE)) == 0)

		return -EINVAL;



	vma->vm_ops = &dma_heap_vm_ops;

	vma->vm_private_data = buffer;



	return 0;

}



static void *cma_heap_do_vmap(struct cma_heap_buffer *buffer)

{

	void *vaddr;



	vaddr = vmap(buffer->pages, buffer->pagecount, VM_MAP, PAGE_KERNEL);

	if (!vaddr)

		return ERR_PTR(-ENOMEM);



	return vaddr;

}



static int cma_heap_vmap(struct dma_buf *dmabuf, struct dma_buf_map *map)

{

	struct cma_heap_buffer *buffer = dmabuf->priv;

	void *vaddr;

	int ret = 0;



	mutex_lock(&buffer->lock);

	if (buffer->vmap_cnt) {

		buffer->vmap_cnt++;

		dma_buf_map_set_vaddr(map, buffer->vaddr);

		goto out;

	}



	vaddr = cma_heap_do_vmap(buffer);

	if (IS_ERR(vaddr)) {

		ret = PTR_ERR(vaddr);

		goto out;

	}

	buffer->vaddr = vaddr;

	buffer->vmap_cnt++;

	dma_buf_map_set_vaddr(map, buffer->vaddr);

out:

	mutex_unlock(&buffer->lock);



	return ret;

}



static void cma_heap_vunmap(struct dma_buf *dmabuf, struct dma_buf_map *map)

{

	struct cma_heap_buffer *buffer = dmabuf->priv;



	mutex_lock(&buffer->lock);

	if (!--buffer->vmap_cnt) {

		vunmap(buffer->vaddr);

		buffer->vaddr = NULL;

	}

	mutex_unlock(&buffer->lock);

	dma_buf_map_clear(map);

}



static void cma_heap_dma_buf_release(struct dma_buf *dmabuf)

{

	struct cma_heap_buffer *buffer = dmabuf->priv;

	struct cma_heap *cma_heap = buffer->heap;



	if (buffer->vmap_cnt > 0) {

		WARN(1, "%s: buffer still mapped in the kernel\n", __func__);

		vunmap(buffer->vaddr);

		buffer->vaddr = NULL;

	}



	cma_release(cma_heap->cma, buffer->cma_pages, buffer->pagecount);

	kfree(buffer);

}



/* dmabuf heap CMA operations functions */

static const struct dma_buf_ops cma_heap_buf_ops = {

	.attach = cma_heap_attach,

	.detach = cma_heap_detach,

	.map_dma_buf = cma_heap_map_dma_buf,

	.unmap_dma_buf = cma_heap_unmap_dma_buf,

	.begin_cpu_access = cma_heap_dma_buf_begin_cpu_access,

	.end_cpu_access = cma_heap_dma_buf_end_cpu_access,

	.mmap = cma_heap_mmap,

	.vmap = cma_heap_vmap,

	.vunmap = cma_heap_vunmap,

	.release = cma_heap_dma_buf_release,

};



static int cma_heap_allocate(struct dma_heap *heap,

				  unsigned long len,

				  unsigned long fd_flags,

				  unsigned long heap_flags)

{

	struct cma_heap *cma_heap = dma_heap_get_drvdata(heap);

	struct heap_helper_buffer *helper_buffer;

	struct page *cma_pages;

	struct cma_heap_buffer *buffer;

	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);

	size_t size = PAGE_ALIGN(len);

	unsigned long nr_pages = size >> PAGE_SHIFT;

	pgoff_t pagecount = size >> PAGE_SHIFT;

	unsigned long align = get_order(size);

	struct page *cma_pages;

	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)

	buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);

	if (!buffer)

		return -ENOMEM;



	init_heap_helper_buffer(helper_buffer, cma_heap_free);

	helper_buffer->heap = heap;

	helper_buffer->size = len;

	INIT_LIST_HEAD(&buffer->attachments);

	mutex_init(&buffer->lock);

	buffer->len = size;



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

	if (align > CONFIG_CMA_ALIGNMENT)

		align = CONFIG_CMA_ALIGNMENT;



	cma_pages = cma_alloc(cma_heap->cma, pagecount, align, false);

	if (!cma_pages)

		goto free_buf;

		goto free_buffer;



	/* Clear the cma pages */

	if (PageHighMem(cma_pages)) {

		unsigned long nr_clear_pages = nr_pages;

		unsigned long nr_clear_pages = pagecount;

		struct page *page = cma_pages;



		while (nr_clear_pages > 0) {
@@ -85,7 +304,6 @@ static int cma_heap_allocate(struct dma_heap *heap, 
			 */

			if (fatal_signal_pending(current))

				goto free_cma;



			page++;

			nr_clear_pages--;

		}
@@ -93,28 +311,30 @@ static int cma_heap_allocate(struct dma_heap *heap, 
		memset(page_address(cma_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) {

	buffer->pages = kmalloc_array(pagecount, sizeof(*buffer->pages), GFP_KERNEL);

	if (!buffer->pages) {

		ret = -ENOMEM;

		goto free_cma;

	}



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

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

	for (pg = 0; pg < pagecount; pg++)

		buffer->pages[pg] = &cma_pages[pg];



	buffer->cma_pages = cma_pages;

	buffer->heap = cma_heap;

	buffer->pagecount = pagecount;



	/* create the dmabuf */

	dmabuf = heap_helper_export_dmabuf(helper_buffer, fd_flags);

	exp_info.ops = &cma_heap_buf_ops;

	exp_info.size = buffer->len;

	exp_info.flags = fd_flags;

	exp_info.priv = buffer;

	dmabuf = dma_buf_export(&exp_info);

	if (IS_ERR(dmabuf)) {

		ret = PTR_ERR(dmabuf);

		goto free_pages;

	}



	helper_buffer->dmabuf = dmabuf;

	helper_buffer->priv_virt = cma_pages;



	ret = dma_buf_fd(dmabuf, fd_flags);

	if (ret < 0) {

		dma_buf_put(dmabuf);
@@ -125,11 +345,12 @@ static int cma_heap_allocate(struct dma_heap *heap, 
	return ret;



free_pages:

	kfree(helper_buffer->pages);

	kfree(buffer->pages);

free_cma:

	cma_release(cma_heap->cma, cma_pages, nr_pages);

free_buf:

	kfree(helper_buffer);

	cma_release(cma_heap->cma, cma_pages, pagecount);

free_buffer:

	kfree(buffer);



	return ret;

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE