Add unlocked variant of dma_buf_map/unmap_attachment() that will
be used by drivers that don't take the reservation lock explicitly.
Acked-by: Sumit Semwal <sumit.semwal@xxxxxxxxxx>
Acked-by: Christian König <christian.koenig@xxxxxxx>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>
---
drivers/dma-buf/dma-buf.c | 53 +++++++++++++++++++++++++++++++++++++++
include/linux/dma-buf.h | 6 +++++
2 files changed, 59 insertions(+)
diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
index e95fc8dc3aed..3e4060dadb74 100644
--- a/drivers/dma-buf/dma-buf.c
+++ b/drivers/dma-buf/dma-buf.c
@@ -1100,6 +1100,34 @@ struct sg_table *dma_buf_map_attachment(struct dma_buf_attachment *attach,
}
EXPORT_SYMBOL_NS_GPL(dma_buf_map_attachment, DMA_BUF);
+/**
+ * dma_buf_map_attachment_unlocked - Returns the scatterlist table of the attachment;
+ * mapped into _device_ address space. Is a wrapper for map_dma_buf() of the
+ * dma_buf_ops.
+ * @attach: [in] attachment whose scatterlist is to be returned
+ * @direction: [in] direction of DMA transfer
+ *
+ * Unlocked variant of dma_buf_map_attachment().
+ */
+struct sg_table *
+dma_buf_map_attachment_unlocked(struct dma_buf_attachment *attach,
+ enum dma_data_direction direction)
+{
+ struct sg_table *sg_table;
+
+ might_sleep();
+
+ if (WARN_ON(!attach || !attach->dmabuf))
+ return ERR_PTR(-EINVAL);
+
+ dma_resv_lock(attach->dmabuf->resv, NULL);
+ sg_table = dma_buf_map_attachment(attach, direction);
+ dma_resv_unlock(attach->dmabuf->resv);
+
+ return sg_table;
+}
+EXPORT_SYMBOL_NS_GPL(dma_buf_map_attachment_unlocked, DMA_BUF);
+
/**
* dma_buf_unmap_attachment - unmaps and decreases usecount of the buffer;might
* deallocate the scatterlist associated. Is a wrapper for unmap_dma_buf() of
@@ -1136,6 +1164,31 @@ void dma_buf_unmap_attachment(struct dma_buf_attachment *attach,
}
EXPORT_SYMBOL_NS_GPL(dma_buf_unmap_attachment, DMA_BUF);
+/**
+ * dma_buf_unmap_attachment_unlocked - unmaps and decreases usecount of the buffer;might
+ * deallocate the scatterlist associated. Is a wrapper for unmap_dma_buf() of
+ * dma_buf_ops.
+ * @attach: [in] attachment to unmap buffer from
+ * @sg_table: [in] scatterlist info of the buffer to unmap
+ * @direction: [in] direction of DMA transfer
+ *
+ * Unlocked variant of dma_buf_unmap_attachment().
+ */
+void dma_buf_unmap_attachment_unlocked(struct dma_buf_attachment *attach,
+ struct sg_table *sg_table,
+ enum dma_data_direction direction)
+{
+ might_sleep();
+
+ if (WARN_ON(!attach || !attach->dmabuf || !sg_table))
+ return;
+
+ dma_resv_lock(attach->dmabuf->resv, NULL);
+ dma_buf_unmap_attachment(attach, sg_table, direction);
+ dma_resv_unlock(attach->dmabuf->resv);
+}
+EXPORT_SYMBOL_NS_GPL(dma_buf_unmap_attachment_unlocked, DMA_BUF);
+
/**
* dma_buf_move_notify - notify attachments that DMA-buf is moving
*
diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h
index 8daa054dd7fe..f11b5bbc2f37 100644
--- a/include/linux/dma-buf.h
+++ b/include/linux/dma-buf.h
@@ -627,6 +627,12 @@ int dma_buf_begin_cpu_access(struct dma_buf *dma_buf,
enum dma_data_direction dir);
int dma_buf_end_cpu_access(struct dma_buf *dma_buf,
enum dma_data_direction dir);
+struct sg_table *
+dma_buf_map_attachment_unlocked(struct dma_buf_attachment *attach,
+ enum dma_data_direction direction);
+void dma_buf_unmap_attachment_unlocked(struct dma_buf_attachment *attach,
+ struct sg_table *sg_table,
+ enum dma_data_direction direction);
int dma_buf_mmap(struct dma_buf *, struct vm_area_struct *,
unsigned long);
--
2.37.3
