[PATCH 009/115] gpu: ion: Allocate the sg_table at creation time rather than dynamically

John Stultz
2013-12-13T22:48:53Z

From: Rebecca Schultz Zavin <rebecca@android.com>

Rather than calling map_dma on the allocations dynamically, this patch
switches to creating the sg_table at the time the buffer is created.
This is necessary because in future updates the sg_table will be used
for cache maintenance.

Signed-off-by: Rebecca Schultz Zavin <rebecca@android.com>
[jstultz: modified patch to apply to staging directory]
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
drivers/staging/android/ion/ion.c | 79 ++++++++++++++++++++-------------------
1 file changed, 41 insertions(+), 38 deletions(-)

diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c
index 8937618..b95202b 100644
--- a/drivers/staging/android/ion/ion.c
+++ b/drivers/staging/android/ion/ion.c
@@ -135,6 +135,7 @@ static struct ion_buffer *ion_buffer_create(struct ion_heap *heap,
unsigned long flags)
{
struct ion_buffer *buffer;
+ struct sg_table *table;
int ret;

buffer = kzalloc(sizeof(struct ion_buffer), GFP_KERNEL);
@@ -149,6 +150,15 @@ static struct ion_buffer *ion_buffer_create(struct ion_heap *heap,
kfree(buffer);
return ERR_PTR(ret);
}
+
+ table = buffer->heap->ops->map_dma(buffer->heap, buffer);
+ if (IS_ERR_OR_NULL(table)) {
+ heap->ops->free(buffer);
+ kfree(buffer);
+ return ERR_PTR(PTR_ERR(table));
+ }
+ buffer->sg_table = table;
+
buffer->dev = dev;
buffer->size = len;
mutex_init(&buffer->lock);
@@ -164,9 +174,7 @@ static void ion_buffer_destroy(struct kref *kref)
if (WARN_ON(buffer->kmap_cnt > 0))
buffer->heap->ops->unmap_kernel(buffer->heap, buffer);

- if (WARN_ON(buffer->dmap_cnt > 0))
- buffer->heap->ops->unmap_dma(buffer->heap, buffer);
-
+ buffer->heap->ops->unmap_dma(buffer->heap, buffer);
buffer->heap->ops->free(buffer);
mutex_lock(&dev->lock);
rb_erase(&buffer->node, &dev->buffers);
@@ -346,6 +354,7 @@ struct ion_handle *ion_alloc(struct ion_client *client, size_t len,
mutex_unlock(&client->lock);
}

+
return handle;
}

@@ -607,53 +616,42 @@ void ion_client_destroy(struct ion_client *client)
kfree(client);
}

-static struct sg_table *ion_map_dma_buf(struct dma_buf_attachment *attachment,
- enum dma_data_direction direction)
+struct sg_table *ion_map_dma(struct ion_client *client,
+ struct ion_handle *handle)
{
- struct dma_buf *dmabuf = attachment->dmabuf;
- struct ion_buffer *buffer = dmabuf->priv;
+ struct ion_buffer *buffer;
struct sg_table *table;

- mutex_lock(&buffer->lock);
-
- if (!buffer->heap->ops->map_dma) {
- pr_err("%s: map_dma is not implemented by this heap.\n",
+ mutex_lock(&client->lock);
+ if (!ion_handle_validate(client, handle)) {
+ pr_err("%s: invalid handle passed to map_dma.\n",
__func__);
- mutex_unlock(&buffer->lock);
- return ERR_PTR(-ENODEV);
- }
- /* if an sg list already exists for this buffer just return it */
- if (buffer->dmap_cnt) {
- table = buffer->sg_table;
- goto end;
+ mutex_unlock(&client->lock);
+ return ERR_PTR(-EINVAL);
}
-
- /* otherwise call into the heap to create one */
- table = buffer->heap->ops->map_dma(buffer->heap, buffer);
- if (IS_ERR_OR_NULL(table))
- goto err;
- buffer->sg_table = table;
-end:
- buffer->dmap_cnt++;
-err:
- mutex_unlock(&buffer->lock);
+ buffer = handle->buffer;
+ table = buffer->sg_table;
+ mutex_unlock(&client->lock);
return table;
}

-static void ion_unmap_dma_buf(struct dma_buf_attachment *attachment,
- struct sg_table *table,
- enum dma_data_direction direction)
+void ion_unmap_dma(struct ion_client *client, struct ion_handle *handle)
+{
+}
+
+static struct sg_table *ion_map_dma_buf(struct dma_buf_attachment *attachment,
+ enum dma_data_direction direction)
{
struct dma_buf *dmabuf = attachment->dmabuf;
struct ion_buffer *buffer = dmabuf->priv;

- mutex_lock(&buffer->lock);
- buffer->dmap_cnt--;
- if (!buffer->dmap_cnt) {
- buffer->heap->ops->unmap_dma(buffer->heap, buffer);
- buffer->sg_table = NULL;
- }
- mutex_unlock(&buffer->lock);
+ return buffer->sg_table;
+}
+
+static void ion_unmap_dma_buf(struct dma_buf_attachment *attachment,
+ struct sg_table *table,
+ enum dma_data_direction direction)
+{
}

static int ion_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma)
@@ -987,6 +985,11 @@ void ion_device_add_heap(struct ion_device *dev, struct ion_heap *heap)
struct rb_node *parent = NULL;
struct ion_heap *entry;

+ if (!heap->ops->allocate || !heap->ops->free || !heap->ops->map_dma ||
+ !heap->ops->unmap_dma)
+ pr_err("%s: can not add heap with invalid ops struct.\n",
+ __func__);
+
heap->dev = dev;
mutex_lock(&dev->lock);
while (*p) {
--
1.8.3.2