Merge tag 'v3.12-rc4' into next

Merge with mainline to bring in changes to input subsystem that were
committed through other trees.

1 files changed, 33 insertions, 1 deletions

diff --git a/drivers/base/dma-buf.c b/drivers/base/dma-buf.c
index 6687ba74187..1e16cbd61da 100644
--- a/drivers/base/dma-buf.c
+++ b/drivers/base/dma-buf.c
@@ -77,9 +77,36 @@ static int dma_buf_mmap_internal(struct file *file, struct vm_area_struct *vma)
 	return dmabuf->ops->mmap(dmabuf, vma);
 }
 
+static loff_t dma_buf_llseek(struct file *file, loff_t offset, int whence)
+{
+	struct dma_buf *dmabuf;
+	loff_t base;
+
+	if (!is_dma_buf_file(file))
+		return -EBADF;
+
+	dmabuf = file->private_data;
+
+	/* only support discovering the end of the buffer,
+	   but also allow SEEK_SET to maintain the idiomatic
+	   SEEK_END(0), SEEK_CUR(0) pattern */
+	if (whence == SEEK_END)
+		base = dmabuf->size;
+	else if (whence == SEEK_SET)
+		base = 0;
+	else
+		return -EINVAL;
+
+	if (offset != 0)
+		return -EINVAL;
+
+	return base + offset;
+}
+
 static const struct file_operations dma_buf_fops = {
 	.release	= dma_buf_release,
 	.mmap		= dma_buf_mmap_internal,
+	.llseek		= dma_buf_llseek,
 };
 
 /*
@@ -133,7 +160,12 @@ struct dma_buf *dma_buf_export_named(void *priv, const struct dma_buf_ops *ops,
 	dmabuf->exp_name = exp_name;
 
 	file = anon_inode_getfile("dmabuf", &dma_buf_fops, dmabuf, flags);
+	if (IS_ERR(file)) {
+		kfree(dmabuf);
+		return ERR_CAST(file);
+	}
 
+	file->f_mode |= FMODE_LSEEK;
 	dmabuf->file = file;
 
 	mutex_init(&dmabuf->lock);
@@ -680,7 +712,7 @@ int dma_buf_debugfs_create_file(const char *name,
 	d = debugfs_create_file(name, S_IRUGO, dma_buf_debugfs_dir,
 			write, &dma_buf_debug_fops);
 
-	return PTR_RET(d);
+	return PTR_ERR_OR_ZERO(d);
 }
 #else
 static inline int dma_buf_init_debugfs(void)