diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 13884474d1588f7a086154d3b06dbd09ff28e881..9058d61b2bb0c6a3182aa2a6371a249d8052f8c5 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -34,6 +34,7 @@ #include <linux/poll.h> #include <linux/reservation.h> #include <linux/mm.h> +#include <linux/device.h> #include <uapi/linux/dma-buf.h> @@ -287,6 +288,36 @@ static long dma_buf_ioctl(struct file *file, dmabuf = file->private_data; switch (cmd) { + case DMA_BUF_IOCTL_PHYS: { + struct dma_buf_attachment *attachment = NULL; + struct sg_table *sgt = NULL; + unsigned long phys = 0; + struct device dev; + + if (!dmabuf || IS_ERR(dmabuf)) { + return -EFAULT; + } + memset(&dev, 0, sizeof(dev)); + device_initialize(&dev); + dev.coherent_dma_mask = DMA_BIT_MASK(64); + dev.dma_mask = &dev.coherent_dma_mask; + arch_setup_dma_ops(&dev, 0, 0, NULL, false); + attachment = dma_buf_attach(dmabuf, &dev); + if (!attachment || IS_ERR(attachment)) { + return -EFAULT; + } + + sgt = dma_buf_map_attachment(attachment, DMA_BIDIRECTIONAL); + if (sgt && !IS_ERR(sgt)) { + phys = sg_dma_address(sgt->sgl); + dma_buf_unmap_attachment(attachment, sgt, + DMA_BIDIRECTIONAL); + } + dma_buf_detach(dmabuf, attachment); + if (copy_to_user((void __user *) arg, &phys, sizeof(phys))) + return -EFAULT; + return 0; + } case DMA_BUF_IOCTL_SYNC: if (copy_from_user(&sync, (void __user *) arg, sizeof(sync))) return -EFAULT; diff --git a/include/uapi/linux/dma-buf.h b/include/uapi/linux/dma-buf.h index d75df5210a4a597b844f20ab8bcca2da7ddf227b..514beecd2d1364aefe29b9db0477f968df041827 100644 --- a/include/uapi/linux/dma-buf.h +++ b/include/uapi/linux/dma-buf.h @@ -27,6 +27,10 @@ struct dma_buf_sync { __u64 flags; }; +struct dma_buf_phys { + unsigned long phys; +}; + #define DMA_BUF_SYNC_READ (1 << 0) #define DMA_BUF_SYNC_WRITE (2 << 0) #define DMA_BUF_SYNC_RW (DMA_BUF_SYNC_READ | DMA_BUF_SYNC_WRITE) @@ -37,5 +41,6 @@ struct dma_buf_sync { #define DMA_BUF_BASE 'b' #define DMA_BUF_IOCTL_SYNC _IOW(DMA_BUF_BASE, 0, struct dma_buf_sync) +#define DMA_BUF_IOCTL_PHYS _IOW(DMA_BUF_BASE, 1, struct dma_buf_phys) #endif