[PATCH v3] staging: android: ion: Add implementation of dma_buf_vmap and dma_buf_vunmap

From: Alexey Skidanov
Date: Wed Jan 31 2018 - 07:04:33 EST


Any driver may access shared buffers, created by ion, using dma_buf_vmap and
dma_buf_vunmap dma-buf API that maps/unmaps previosuly allocated buffers into
the kernel virtual address space. The implementation of these API is missing in
the current ion implementation.

Signed-off-by: Alexey Skidanov <alexey.skidanov@xxxxxxxxx>
---
drivers/staging/android/ion/ion.c | 13 +++++++++++++
1 file changed, 13 insertions(+)

diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c
index f480885..4f1dc7f 100644
--- a/drivers/staging/android/ion/ion.c
+++ b/drivers/staging/android/ion/ion.c
@@ -327,6 +327,17 @@ static void ion_dma_buf_kunmap(struct dma_buf *dmabuf, unsigned long offset,
{
}

+static void *ion_dma_buf_vmap(struct dma_buf *dmabuf)
+{
+ struct ion_buffer *buffer = dmabuf->priv;
+
+ return buffer->vaddr;
+}
+
+static void ion_dma_buf_vunmap(struct dma_buf *dmabuf, void *vaddr)
+{
+}
+
static int ion_dma_buf_begin_cpu_access(struct dma_buf *dmabuf,
enum dma_data_direction direction)
{
@@ -388,6 +399,8 @@ static const struct dma_buf_ops dma_buf_ops = {
.unmap_atomic = ion_dma_buf_kunmap,
.map = ion_dma_buf_kmap,
.unmap = ion_dma_buf_kunmap,
+ .vmap = ion_dma_buf_vmap,
+ .vunmap = ion_dma_buf_vunmap
};

int ion_alloc(size_t len, unsigned int heap_id_mask, unsigned int flags)
--
2.7.4