[PATCH v2 12/64] dmaengine: mv_xor: convert irq tasklet to dma_chan BH

Allen Pais <[email protected]> Mon, 27 Jul 2026 13:28:40 -0700
Newsgroups org.kernel.vger.dmaengine,org.kernel.vger.linux-kernel
Message-ID <f558c55dfee41aa28bf47f32c15e7c56be003c39.1785183549.git.allen.lkml@gmail.com>
Replace the per-channel tasklet with the shared dma_chan BH helper.
The handler continues to run in softirq context while dmaengine owns
the common scheduling and teardown mechanism.

Signed-off-by: Allen Pais <[email protected]>
---
 drivers/dma/mv_xor.c | 12 ++++++------
 drivers/dma/mv_xor.h |  2 --
 2 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c
index 25ed61f1b089..3a70d565e1ef 100644
--- a/drivers/dma/mv_xor.c
+++ b/drivers/dma/mv_xor.c
@@ -327,7 +327,7 @@ static void mv_chan_slot_cleanup(struct mv_xor_chan *mv_chan)
 				 * some descriptors are still waiting
 				 * to be cleaned
 				 */
-				tasklet_schedule(&mv_chan->irq_tasklet);
+				dma_chan_schedule_bh(&mv_chan->dmachan);
 			}
 		}
 	}
@@ -336,9 +336,9 @@ static void mv_chan_slot_cleanup(struct mv_xor_chan *mv_chan)
 		mv_chan->dmachan.completed_cookie = cookie;
 }
 
-static void mv_xor_tasklet(struct tasklet_struct *t)
+static void mv_xor_tasklet(struct dma_chan *c)
 {
-	struct mv_xor_chan *chan = from_tasklet(chan, t, irq_tasklet);
+	struct mv_xor_chan *chan = to_mv_xor_chan(c);
 
 	spin_lock(&chan->lock);
 	mv_chan_slot_cleanup(chan);
@@ -372,7 +372,7 @@ mv_chan_alloc_slot(struct mv_xor_chan *mv_chan)
 	spin_unlock_bh(&mv_chan->lock);
 
 	/* try to free some slots if the allocation fails */
-	tasklet_schedule(&mv_chan->irq_tasklet);
+	dma_chan_schedule_bh(&mv_chan->dmachan);
 
 	return NULL;
 }
@@ -737,7 +737,7 @@ static irqreturn_t mv_xor_interrupt_handler(int irq, void *data)
 	if (intr_cause & XOR_INTR_ERRORS)
 		mv_chan_err_interrupt_handler(chan, intr_cause);
 
-	tasklet_schedule(&chan->irq_tasklet);
+	dma_chan_schedule_bh(&chan->dmachan);
 
 	mv_chan_clear_eoc_cause(chan);
 
@@ -1107,7 +1107,7 @@ mv_xor_channel_add(struct mv_xor_device *xordev,
 
 	mv_chan->mmr_base = xordev->xor_base;
 	mv_chan->mmr_high_base = xordev->xor_high_base;
-	tasklet_setup(&mv_chan->irq_tasklet, mv_xor_tasklet);
+	dma_chan_init_bh(&mv_chan->dmachan, mv_xor_tasklet);
 
 	/* clear errors before enabling interrupts */
 	mv_chan_clear_err_status(mv_chan);
diff --git a/drivers/dma/mv_xor.h b/drivers/dma/mv_xor.h
index c87cefd38a07..27774abe34a6 100644
--- a/drivers/dma/mv_xor.h
+++ b/drivers/dma/mv_xor.h
@@ -98,7 +98,6 @@ struct mv_xor_device {
  * @device: parent device
  * @common: common dmaengine channel object members
  * @slots_allocated: records the actual size of the descriptor slot pool
- * @irq_tasklet: bottom half where mv_xor_slot_cleanup runs
  * @op_in_desc: new mode of driver, each op is written to descriptor.
  */
 struct mv_xor_chan {
@@ -118,7 +117,6 @@ struct mv_xor_chan {
 	struct dma_device	dmadev;
 	struct dma_chan		dmachan;
 	int			slots_allocated;
-	struct tasklet_struct	irq_tasklet;
 	int                     op_in_desc;
 	char			dummy_src[MV_XOR_MIN_BYTE_COUNT];
 	char			dummy_dst[MV_XOR_MIN_BYTE_COUNT];
-- 
2.43.0