[PATCH] dma-buf: support 32bit DMA_BUF_SET_NAME ioctl

[Martin Liu <liumartin@google.com>]

This commit adds SET_NAME ioctl coversion to
support 32 bit ioctl.

Signed-off-by: Martin Liu <liumartin@google.com>
---
 drivers/dma-buf/dma-buf.c | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
index ce41cd9b758a..a73048b34843 100644
--- a/drivers/dma-buf/dma-buf.c
+++ b/drivers/dma-buf/dma-buf.c
@@ -25,6 +25,7 @@
 #include <linux/mm.h>
 #include <linux/mount.h>
 #include <linux/pseudo_fs.h>
+#include <linux/compat.h>
 
 #include <uapi/linux/dma-buf.h>
 #include <uapi/linux/magic.h>
@@ -409,13 +410,32 @@ static void dma_buf_show_fdinfo(struct seq_file *m, struct file *file)
 	dma_resv_unlock(dmabuf->resv);
 }
 
+#ifdef CONFIG_COMPAT
+static long dma_buf_ioctl_compat(struct file *file, unsigned int cmd,
+				 unsigned long arg)
+{
+	switch (_IOC_NR(cmd)) {
+	case _IOC_NR(DMA_BUF_SET_NAME):
+		/* Fix up pointer size*/
+		if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) {
+			cmd &= ~IOCSIZE_MASK;
+			cmd |= sizeof(void *) << IOCSIZE_SHIFT;
+		}
+		break;
+	}
+	return dma_buf_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
+}
+#endif
+
 static const struct file_operations dma_buf_fops = {
 	.release	= dma_buf_release,
 	.mmap		= dma_buf_mmap_internal,
 	.llseek		= dma_buf_llseek,
 	.poll		= dma_buf_poll,
 	.unlocked_ioctl	= dma_buf_ioctl,
-	.compat_ioctl	= compat_ptr_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl	= dma_buf_ioctl_compat,
+#endif
 	.show_fdinfo	= dma_buf_show_fdinfo,
 };
 
-- 
2.25.0.rc1.283.g88dfdc4193-goog