From: Hans Verkuil <hans.verkuil@xxxxxxxxx>
Add proper locking to the file operations, allowing for the removal
of the V4L2_FL_LOCK_ALL_FOPS flag.
Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
---
drivers/media/video/mem2mem_testdev.c | 29 ++++++++++++++++++++---------
1 file changed, 20 insertions(+), 9 deletions(-)
diff --git a/drivers/media/video/mem2mem_testdev.c b/drivers/media/video/mem2mem_testdev.c
index d2dec58..595e268 100644
--- a/drivers/media/video/mem2mem_testdev.c
+++ b/drivers/media/video/mem2mem_testdev.c
@@ -849,10 +849,15 @@ static int m2mtest_open(struct file *file)
{
struct m2mtest_dev *dev = video_drvdata(file);
struct m2mtest_ctx *ctx = NULL;
+ int rc = 0;
+ if (mutex_lock_interruptible(&dev->dev_mutex))
+ return -ERESTARTSYS;
ctx = kzalloc(sizeof *ctx, GFP_KERNEL);
- if (!ctx)
- return -ENOMEM;
+ if (!ctx) {
+ rc = -ENOMEM;
+ goto open_unlock;
+ }
file->private_data = ctx;
ctx->dev = dev;
@@ -863,16 +868,18 @@ static int m2mtest_open(struct file *file)
ctx->m2m_ctx = v4l2_m2m_ctx_init(dev->m2m_dev, ctx, &queue_init);
if (IS_ERR(ctx->m2m_ctx)) {
- int ret = PTR_ERR(ctx->m2m_ctx);
+ rc = PTR_ERR(ctx->m2m_ctx);
kfree(ctx);
- return ret;
+ goto open_unlock;
}
atomic_inc(&dev->num_inst);
dprintk(dev, "Created instance %p, m2m_ctx: %p\n", ctx, ctx->m2m_ctx);
+open_unlock:
+ mutex_unlock(&dev->dev_mutex);
return 0;
}
@@ -883,7 +890,9 @@ static int m2mtest_release(struct file *file)
dprintk(dev, "Releasing instance %p\n", ctx);
+ mutex_lock(&dev->dev_mutex);
v4l2_m2m_ctx_release(ctx->m2m_ctx);
+ mutex_unlock(&dev->dev_mutex);
kfree(ctx);
atomic_dec(&dev->num_inst);
@@ -901,9 +910,15 @@ static unsigned int m2mtest_poll(struct file *file,
static int m2mtest_mmap(struct file *file, struct vm_area_struct *vma)
{
+ struct m2mtest_dev *dev = video_drvdata(file);
struct m2mtest_ctx *ctx = file->private_data;
+ int res;
- return v4l2_m2m_mmap(file, ctx->m2m_ctx, vma);
+ if (mutex_lock_interruptible(&dev->dev_mutex))
+ return -ERESTARTSYS;
+ res = v4l2_m2m_mmap(file, ctx->m2m_ctx, vma);
+ mutex_unlock(&dev->dev_mutex);
+ return res;
}
static const struct v4l2_file_operations m2mtest_fops = {
@@ -958,10 +973,6 @@ static int m2mtest_probe(struct platform_device *pdev)
}
*vfd = m2mtest_videodev;
- /* Locking in file operations other than ioctl should be done
- by the driver, not the V4L2 core.
- This driver needs auditing so that this flag can be removed. */
- set_bit(V4L2_FL_LOCK_ALL_FOPS, &vfd->flags);
vfd->lock = &dev->dev_mutex;
ret = video_register_device(vfd, VFL_TYPE_GRABBER, 0);
--
1.7.10
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
