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It wraps open-coded kref_get_unless_zero() and asserts that > dma_list_mutex is held, matching its put counterpart. > > No functional change intended. > > Suggested-by: Frank Li > Signed-off-by: Shivank Garg > --- > drivers/dma/dmaengine.c | 9 +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) > > diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c > index 6ffd8bd82154..77638dc16e71 100644 > --- a/drivers/dma/dmaengine.c > +++ b/drivers/dma/dmaengine.c > @@ -433,6 +433,12 @@ static void dma_device_release(struct kref *ref) > device->device_release(device); > } > > +static bool dma_device_get(struct dma_device *device) Please the same return type of kref_get_unless_zero(), it should be int. Frank > +{ > + lockdep_assert_held(&dma_list_mutex); > + return kref_get_unless_zero(&device->ref); > +} > + > static void dma_device_put(struct dma_device *device) > { > lockdep_assert_held(&dma_list_mutex); > @@ -460,8 +466,7 @@ static int dma_chan_get(struct dma_chan *chan) > if (!try_module_get(owner)) > return -ENODEV; > > - ret = kref_get_unless_zero(&chan->device->ref); > - if (!ret) { > + if (!dma_device_get(chan->device)) { > ret = -ENODEV; > goto module_put_out; > } > > -- > 2.43.0 >