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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. > > > > Thanks, refcount_inc_not_zero() (and callees) returns bool to > kref_get_unless_zero(). I used bool because of boolean result value, > but I have no strong opinion here. I'll change dma_device_get() to > return int to match kref_get_unless_zero(). > > > I think I should also add __must_check attribute, since kref_get_unless_zero() > has it. Yes, Frank > > Thanks, > Shivank