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@linaro.org Acked-by: Christian König christian.koenig@amd.com Signed-off-by: Dmitry Osipenko dmitry.osipenko@collabora.com --- 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);