[PATCH 008/115] gpu: ion: support begin/end and kmap/kunmap dma_buf ops

John Stultz
2013-12-13T22:49:34Z

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

These ops were added in the 3.4 kernel. This patch adds support
for them to ion. Previous ion_map/unmap_kernel api is also
retained in addition to this new api.

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 | 88 +++++++++++++++++++++++++++------------
1 file changed, 62 insertions(+), 26 deletions(-)

diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c
index 75bf8f2..8937618 100644
--- a/drivers/staging/android/ion/ion.c
+++ b/drivers/staging/android/ion/ion.c
@@ -391,6 +391,22 @@ int ion_phys(struct ion_client *client, struct ion_handle *handle,
return ret;
}

+static void *ion_buffer_kmap_get(struct ion_buffer *buffer)
+{
+ void *vaddr;
+
+ if (buffer->kmap_cnt) {
+ buffer->kmap_cnt++;
+ return buffer->vaddr;
+ }
+ vaddr = buffer->heap->ops->map_kernel(buffer->heap, buffer);
+ if (IS_ERR_OR_NULL(vaddr))
+ return vaddr;
+ buffer->vaddr = vaddr;
+ buffer->kmap_cnt++;
+ return vaddr;
+}
+
static void *ion_handle_kmap_get(struct ion_handle *handle)
{
struct ion_buffer *buffer = handle->buffer;
@@ -399,34 +415,30 @@ static void *ion_handle_kmap_get(struct ion_handle *handle)
if (handle->kmap_cnt) {
handle->kmap_cnt++;
return buffer->vaddr;
- } else if (buffer->kmap_cnt) {
- handle->kmap_cnt++;
- buffer->kmap_cnt++;
- return buffer->vaddr;
}
-
- vaddr = buffer->heap->ops->map_kernel(buffer->heap, buffer);
- buffer->vaddr = vaddr;
- if (IS_ERR_OR_NULL(vaddr)) {
- buffer->vaddr = NULL;
+ vaddr = ion_buffer_kmap_get(buffer);
+ if (IS_ERR_OR_NULL(vaddr))
return vaddr;
- }
handle->kmap_cnt++;
- buffer->kmap_cnt++;
return vaddr;
}

+static void ion_buffer_kmap_put(struct ion_buffer *buffer)
+{
+ buffer->kmap_cnt--;
+ if (!buffer->kmap_cnt) {
+ buffer->heap->ops->unmap_kernel(buffer->heap, buffer);
+ buffer->vaddr = NULL;
+ }
+}
+
static void ion_handle_kmap_put(struct ion_handle *handle)
{
struct ion_buffer *buffer = handle->buffer;

handle->kmap_cnt--;
if (!handle->kmap_cnt)
- buffer->kmap_cnt--;
- if (!buffer->kmap_cnt) {
- buffer->heap->ops->unmap_kernel(buffer->heap, buffer);
- buffer->vaddr = NULL;
- }
+ ion_buffer_kmap_put(buffer);
}

void *ion_map_kernel(struct ion_client *client, struct ion_handle *handle)
@@ -675,7 +687,8 @@ static void ion_dma_buf_release(struct dma_buf *dmabuf)

static void *ion_dma_buf_kmap(struct dma_buf *dmabuf, unsigned long offset)
{
- return NULL;
+ struct ion_buffer *buffer = dmabuf->priv;
+ return buffer->vaddr + offset;
}

static void ion_dma_buf_kunmap(struct dma_buf *dmabuf, unsigned long offset,
@@ -684,26 +697,49 @@ static void ion_dma_buf_kunmap(struct dma_buf *dmabuf, unsigned long offset,
return;
}

-static void *ion_dma_buf_kmap_atomic(struct dma_buf *dmabuf,
- unsigned long offset)
+static int ion_dma_buf_begin_cpu_access(struct dma_buf *dmabuf, size_t start,
+ size_t len,
+ enum dma_data_direction direction)
{
- return NULL;
+ struct ion_buffer *buffer = dmabuf->priv;
+ void *vaddr;
+
+ if (!buffer->heap->ops->map_kernel) {
+ pr_err("%s: map kernel is not implemented by this heap.\n",
+ __func__);
+ return -ENODEV;
+ }
+
+ mutex_lock(&buffer->lock);
+ vaddr = ion_buffer_kmap_get(buffer);
+ mutex_unlock(&buffer->lock);
+ if (IS_ERR(vaddr))
+ return PTR_ERR(vaddr);
+ if (!vaddr)
+ return -ENOMEM;
+ return 0;
}

-static void ion_dma_buf_kunmap_atomic(struct dma_buf *dmabuf,
- unsigned long offset, void *ptr)
+static void ion_dma_buf_end_cpu_access(struct dma_buf *dmabuf, size_t start,
+ size_t len,
+ enum dma_data_direction direction)
{
- return;
-}
+ struct ion_buffer *buffer = dmabuf->priv;

+ mutex_lock(&buffer->lock);
+ ion_buffer_kmap_put(buffer);
+ mutex_unlock(&buffer->lock);
+}

struct dma_buf_ops dma_buf_ops = {
.map_dma_buf = ion_map_dma_buf,
.unmap_dma_buf = ion_unmap_dma_buf,
.mmap = ion_mmap,
.release = ion_dma_buf_release,
- .kmap_atomic = ion_dma_buf_kmap_atomic,
- .kunmap_atomic = ion_dma_buf_kunmap_atomic,
+ .begin_cpu_access = ion_dma_buf_begin_cpu_access,
+ .end_cpu_access = ion_dma_buf_end_cpu_access,
+ .kmap_atomic = ion_dma_buf_kmap,
+ .kunmap_atomic = ion_dma_buf_kunmap,
.kmap = ion_dma_buf_kmap,
.kunmap = ion_dma_buf_kunmap,
};
--
1.8.3.2