Re: [PATCH 1/1] dmaengine: change dmaengine_get_unmap_data() first arg to dma_chan
From: Dave Jiang
Date: Tue Sep 22 2026 - 19:09:40 EST
On 9/22/26 11:45 AM, Frank.Li@xxxxxxxxxxx wrote:
> From: Frank Li <Frank.Li@xxxxxxx>
>
> Replace the struct device *dev argument with struct dma_chan *chan so
> callers do not need to reach into the dma_device internals to obtain
> the device pointer. The implementation now derives the device via
> dmaengine_get_dma_device(chan), which correctly handles the per-channel
> IOMMU mapping case.
>
> Prepare to make dma_device private and make dmaengine API consistent.
>
> Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
For the NTB bits:
Acked-by: Dave Jiang <dave.jiang@xxxxxxxxx>
> ---
> crypto/async_tx/async_memcpy.c | 4 ++--
> crypto/async_tx/async_pq.c | 4 ++--
> crypto/async_tx/async_raid6_recov.c | 4 ++--
> crypto/async_tx/async_xor.c | 8 ++++----
Maybe one day Dan's wishes will become true and someone will finally deprecate async_tx....
DJ> drivers/dma/dmaengine.c | 4 ++--
> drivers/dma/dmatest.c | 2 +-
> drivers/dma/mv_xor.c | 4 ++--
> drivers/ntb/ntb_transport.c | 4 ++--
> drivers/ntb/test/ntb_perf.c | 2 +-
> include/linux/dmaengine.h | 4 ++--
> 10 files changed, 20 insertions(+), 20 deletions(-)
>
> diff --git a/crypto/async_tx/async_memcpy.c b/crypto/async_tx/async_memcpy.c
> index 323152c89b3a1..d03e9a9bc1e2d 100644
> --- a/crypto/async_tx/async_memcpy.c
> +++ b/crypto/async_tx/async_memcpy.c
> @@ -39,8 +39,8 @@ async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset,
> struct dma_async_tx_descriptor *tx = NULL;
> struct dmaengine_unmap_data *unmap = NULL;
>
> - if (device)
> - unmap = dmaengine_get_unmap_data(device->dev, 2, GFP_NOWAIT);
> + if (chan)
> + unmap = dmaengine_get_unmap_data(chan, 2, GFP_NOWAIT);
>
> if (unmap && dmaengine_is_copy_aligned(chan, src_offset, dest_offset, len)) {
> unsigned long dma_prep_flags = 0;
> diff --git a/crypto/async_tx/async_pq.c b/crypto/async_tx/async_pq.c
> index fcc8d9ebc0fec..6a31271852cd4 100644
> --- a/crypto/async_tx/async_pq.c
> +++ b/crypto/async_tx/async_pq.c
> @@ -188,7 +188,7 @@ async_gen_syndrome(struct page **blocks, unsigned int *offsets, int disks,
> BUG_ON(disks > MAX_DISKS || !(P(blocks, disks) || Q(blocks, disks)));
>
> if (device)
> - unmap = dmaengine_get_unmap_data(device->dev, disks, GFP_NOWAIT);
> + unmap = dmaengine_get_unmap_data(chan, disks, GFP_NOWAIT);
>
> /* XORing P/Q is only implemented in software */
> if (unmap && !(submit->flags & ASYNC_TX_PQ_XOR_DST) &&
> @@ -310,7 +310,7 @@ async_syndrome_val(struct page **blocks, unsigned int *offsets, int disks,
> BUG_ON(disks < 4 || disks > MAX_DISKS);
>
> if (device)
> - unmap = dmaengine_get_unmap_data(device->dev, disks, GFP_NOWAIT);
> + unmap = dmaengine_get_unmap_data(chan, disks, GFP_NOWAIT);
>
> if (unmap && disks <= dma_maxpq(device, 0) &&
> is_dma_pq_aligned_offs(chan, offsets, disks, len)) {
> diff --git a/crypto/async_tx/async_raid6_recov.c b/crypto/async_tx/async_raid6_recov.c
> index 27909afda694a..5055531145bd2 100644
> --- a/crypto/async_tx/async_raid6_recov.c
> +++ b/crypto/async_tx/async_raid6_recov.c
> @@ -29,7 +29,7 @@ async_sum_product(struct page *dest, unsigned int d_off,
> u8 *a, *b, *c;
>
> if (dma)
> - unmap = dmaengine_get_unmap_data(dma->dev, 3, GFP_NOWAIT);
> + unmap = dmaengine_get_unmap_data(chan, 3, GFP_NOWAIT);
>
> if (unmap) {
> struct device *dev = dma->dev;
> @@ -97,7 +97,7 @@ async_mult(struct page *dest, unsigned int d_off, struct page *src,
> u8 *d, *s;
>
> if (dma)
> - unmap = dmaengine_get_unmap_data(dma->dev, 3, GFP_NOWAIT);
> + unmap = dmaengine_get_unmap_data(chan, 3, GFP_NOWAIT);
>
> if (unmap) {
> dma_addr_t dma_dest[2];
> diff --git a/crypto/async_tx/async_xor.c b/crypto/async_tx/async_xor.c
> index 4ed9d3196fc46..9ed331d9b8e64 100644
> --- a/crypto/async_tx/async_xor.c
> +++ b/crypto/async_tx/async_xor.c
> @@ -178,8 +178,8 @@ async_xor_offs(struct page *dest, unsigned int offset,
>
> BUG_ON(src_cnt <= 1);
>
> - if (device)
> - unmap = dmaengine_get_unmap_data(device->dev, src_cnt+1, GFP_NOWAIT);
> + if (chan)
> + unmap = dmaengine_get_unmap_data(chan, src_cnt + 1, GFP_NOWAIT);
>
> if (unmap && dma_xor_aligned_offsets(chan, offset, src_offs,
> src_cnt, len)) {
> @@ -310,8 +310,8 @@ async_xor_val_offs(struct page *dest, unsigned int offset,
>
> BUG_ON(src_cnt <= 1);
>
> - if (device)
> - unmap = dmaengine_get_unmap_data(device->dev, src_cnt, GFP_NOWAIT);
> + if (chan)
> + unmap = dmaengine_get_unmap_data(chan, src_cnt, GFP_NOWAIT);
>
> if (unmap && src_cnt <= device->max_xor &&
> dma_xor_aligned_offsets(chan, offset, src_offs, src_cnt, len)) {
> diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
> index cc1c0a7c9f33d..4585ebcd2e8cd 100644
> --- a/drivers/dma/dmaengine.c
> +++ b/drivers/dma/dmaengine.c
> @@ -1474,7 +1474,7 @@ static int __init dmaengine_init_unmap_pool(void)
> }
>
> struct dmaengine_unmap_data *
> -dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags)
> +dmaengine_get_unmap_data(struct dma_chan *chan, int nr, gfp_t flags)
> {
> struct dmaengine_unmap_data *unmap;
>
> @@ -1484,7 +1484,7 @@ dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags)
>
> memset(unmap, 0, sizeof(*unmap));
> kref_init(&unmap->kref);
> - unmap->dev = dev;
> + unmap->dev = dmaengine_get_dma_device(chan);
> unmap->map_cnt = nr;
>
> return unmap;
> diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c
> index 2ae3469397f37..043bb065dd68a 100644
> --- a/drivers/dma/dmatest.c
> +++ b/drivers/dma/dmatest.c
> @@ -748,7 +748,7 @@ static int dmatest_func(void *data)
> filltime = ktime_add(filltime, diff);
> }
>
> - um = dmaengine_get_unmap_data(dma_dev, src->cnt + dst->cnt,
> + um = dmaengine_get_unmap_data(chan, src->cnt + dst->cnt,
> GFP_KERNEL);
> if (!um) {
> failed_tests++;
> diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c
> index c4e0dce3ca64e..dec01b6264d7a 100644
> --- a/drivers/dma/mv_xor.c
> +++ b/drivers/dma/mv_xor.c
> @@ -794,7 +794,7 @@ static int mv_chan_memcpy_self_test(struct mv_xor_chan *mv_chan)
> goto out;
> }
>
> - unmap = dmaengine_get_unmap_data(dma_chan->device->dev, 2, GFP_KERNEL);
> + unmap = dmaengine_get_unmap_data(dma_chan, 2, GFP_KERNEL);
> if (!unmap) {
> err = -ENOMEM;
> goto free_resources;
> @@ -927,7 +927,7 @@ mv_chan_xor_self_test(struct mv_xor_chan *mv_chan)
> goto out;
> }
>
> - unmap = dmaengine_get_unmap_data(dma_chan->device->dev, src_count + 1,
> + unmap = dmaengine_get_unmap_data(dma_chan, src_count + 1,
> GFP_KERNEL);
> if (!unmap) {
> err = -ENOMEM;
> diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c
> index b8f8b333b89eb..e9e1506df71d6 100644
> --- a/drivers/ntb/ntb_transport.c
> +++ b/drivers/ntb/ntb_transport.c
> @@ -1532,7 +1532,7 @@ static int ntb_async_rx_submit(struct ntb_queue_entry *entry, void *offset)
> if (!dmaengine_is_copy_aligned(chan, pay_off, buff_off, len))
> goto err;
>
> - unmap = dmaengine_get_unmap_data(dma_dev, 2, GFP_NOWAIT);
> + unmap = dmaengine_get_unmap_data(chan, 2, GFP_NOWAIT);
> if (!unmap)
> goto err;
>
> @@ -1871,7 +1871,7 @@ static int ntb_async_tx_submit(struct ntb_transport_qp *qp,
> if (!dmaengine_is_copy_aligned(chan, buff_off, dest_off, len))
> goto err;
>
> - unmap = dmaengine_get_unmap_data(dma_dev, 1, GFP_NOWAIT);
> + unmap = dmaengine_get_unmap_data(chan, 1, GFP_NOWAIT);
> if (!unmap)
> goto err;
>
> diff --git a/drivers/ntb/test/ntb_perf.c b/drivers/ntb/test/ntb_perf.c
> index 774e643c9f4c6..1cb991e2f0cf7 100644
> --- a/drivers/ntb/test/ntb_perf.c
> +++ b/drivers/ntb/test/ntb_perf.c
> @@ -809,7 +809,7 @@ static int perf_copy_chunk(struct perf_thread *pthr,
> dst_vaddr = dst;
> dst_dma_addr = peer->dma_dst_addr + (dst_vaddr - vbase);
>
> - unmap = dmaengine_get_unmap_data(dma_dev, 1, GFP_NOWAIT);
> + unmap = dmaengine_get_unmap_data(pthr->dma_chan, 1, GFP_NOWAIT);
> if (!unmap)
> return -ENOMEM;
>
> diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
> index fc661e76de84d..c8ecf80288f13 100644
> --- a/include/linux/dmaengine.h
> +++ b/include/linux/dmaengine.h
> @@ -656,7 +656,7 @@ static inline void dma_set_unmap(struct dma_async_tx_descriptor *tx,
> }
>
> struct dmaengine_unmap_data *
> -dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags);
> +dmaengine_get_unmap_data(struct dma_chan *chan, int nr, gfp_t flags);
> void dmaengine_unmap_put(struct dmaengine_unmap_data *unmap);
> #else
> static inline void dma_set_unmap(struct dma_async_tx_descriptor *tx,
> @@ -664,7 +664,7 @@ static inline void dma_set_unmap(struct dma_async_tx_descriptor *tx,
> {
> }
> static inline struct dmaengine_unmap_data *
> -dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags)
> +dmaengine_get_unmap_data(struct dma_chan *chan, int nr, gfp_t flags)
> {
> return NULL;
> }