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path: root/drivers/media/v4l2-core/videobuf2-dma-sg.c
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Diffstat (limited to 'drivers/media/v4l2-core/videobuf2-dma-sg.c')
-rw-r--r--drivers/media/v4l2-core/videobuf2-dma-sg.c32
1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/media/v4l2-core/videobuf2-dma-sg.c b/drivers/media/v4l2-core/videobuf2-dma-sg.c
index 2529b831725b..2bf13dc4df34 100644
--- a/drivers/media/v4l2-core/videobuf2-dma-sg.c
+++ b/drivers/media/v4l2-core/videobuf2-dma-sg.c
@@ -30,7 +30,12 @@ module_param(debug, int, 0644);
printk(KERN_DEBUG "vb2-dma-sg: " fmt, ## arg); \
} while (0)
+struct vb2_dma_sg_conf {
+ struct device *dev;
+};
+
struct vb2_dma_sg_buf {
+ struct device *dev;
void *vaddr;
struct page **pages;
int offset;
@@ -89,10 +94,13 @@ static int vb2_dma_sg_alloc_compacted(struct vb2_dma_sg_buf *buf,
static void *vb2_dma_sg_alloc(void *alloc_ctx, unsigned long size,
enum dma_data_direction dma_dir, gfp_t gfp_flags)
{
+ struct vb2_dma_sg_conf *conf = alloc_ctx;
struct vb2_dma_sg_buf *buf;
int ret;
int num_pages;
+ if (WARN_ON(alloc_ctx == NULL))
+ return NULL;
buf = kzalloc(sizeof *buf, GFP_KERNEL);
if (!buf)
return NULL;
@@ -118,6 +126,8 @@ static void *vb2_dma_sg_alloc(void *alloc_ctx, unsigned long size,
if (ret)
goto fail_table_alloc;
+ /* Prevent the device from being released while the buffer is used */
+ buf->dev = get_device(conf->dev);
buf->handler.refcount = &buf->refcount;
buf->handler.put = vb2_dma_sg_put;
buf->handler.arg = buf;
@@ -153,6 +163,7 @@ static void vb2_dma_sg_put(void *buf_priv)
while (--i >= 0)
__free_page(buf->pages[i]);
kfree(buf->pages);
+ put_device(buf->dev);
kfree(buf);
}
}
@@ -356,6 +367,27 @@ const struct vb2_mem_ops vb2_dma_sg_memops = {
};
EXPORT_SYMBOL_GPL(vb2_dma_sg_memops);
+void *vb2_dma_sg_init_ctx(struct device *dev)
+{
+ struct vb2_dma_sg_conf *conf;
+
+ conf = kzalloc(sizeof(*conf), GFP_KERNEL);
+ if (!conf)
+ return ERR_PTR(-ENOMEM);
+
+ conf->dev = dev;
+
+ return conf;
+}
+EXPORT_SYMBOL_GPL(vb2_dma_sg_init_ctx);
+
+void vb2_dma_sg_cleanup_ctx(void *alloc_ctx)
+{
+ if (!IS_ERR_OR_NULL(alloc_ctx))
+ kfree(alloc_ctx);
+}
+EXPORT_SYMBOL_GPL(vb2_dma_sg_cleanup_ctx);
+
MODULE_DESCRIPTION("dma scatter/gather memory handling routines for videobuf2");
MODULE_AUTHOR("Andrzej Pietrasiewicz");
MODULE_LICENSE("GPL");
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