This is a note to let you know that I've just added the patch titled
dmaengine: at_xdmac: Move the free desc to the tail of the desc list
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
dmaengine-at_xdmac-move-the-free-desc-to-the-tail-of.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 70938d5c9bba76b993e88559e4097cddff44b4e9
Author: Tudor Ambarus <tudor.ambarus@xxxxxxxxxx>
Date: Wed Dec 15 13:01:09 2021 +0200
dmaengine: at_xdmac: Move the free desc to the tail of the desc list
[ Upstream commit 801db90bf294f647b967e8d99b9ae121bea63d0d ]
Move the free desc to the tail of the list, so that the sequence of
descriptors is more track-able in case of debug. One would know which
descriptor should come next and could easier catch concurrency over
descriptors for example. virt-dma uses list_splice_tail_init() as well,
follow the core driver.
Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20211215110115.191749-7-tudor.ambarus@xxxxxxxxxxxxx
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Stable-dep-of: 4d43acb145c3 ("dmaengine: at_xdmac: fix potential Oops in at_xdmac_prep_interleaved()")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
index 80c609aa2a91c..b45437aab1434 100644
--- a/drivers/dma/at_xdmac.c
+++ b/drivers/dma/at_xdmac.c
@@ -732,7 +732,8 @@ at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
if (!desc) {
dev_err(chan2dev(chan), "can't get descriptor\n");
if (first)
- list_splice_init(&first->descs_list, &atchan->free_descs_list);
+ list_splice_tail_init(&first->descs_list,
+ &atchan->free_descs_list);
goto spin_unlock;
}
@@ -820,7 +821,8 @@ at_xdmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr,
if (!desc) {
dev_err(chan2dev(chan), "can't get descriptor\n");
if (first)
- list_splice_init(&first->descs_list, &atchan->free_descs_list);
+ list_splice_tail_init(&first->descs_list,
+ &atchan->free_descs_list);
spin_unlock_irqrestore(&atchan->lock, irqflags);
return NULL;
}
@@ -1054,8 +1056,8 @@ at_xdmac_prep_interleaved(struct dma_chan *chan,
src_addr, dst_addr,
xt, chunk);
if (!desc) {
- list_splice_init(&first->descs_list,
- &atchan->free_descs_list);
+ list_splice_tail_init(&first->descs_list,
+ &atchan->free_descs_list);
return NULL;
}
@@ -1135,7 +1137,8 @@ at_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
if (!desc) {
dev_err(chan2dev(chan), "can't get descriptor\n");
if (first)
- list_splice_init(&first->descs_list, &atchan->free_descs_list);
+ list_splice_tail_init(&first->descs_list,
+ &atchan->free_descs_list);
return NULL;
}
@@ -1311,8 +1314,8 @@ at_xdmac_prep_dma_memset_sg(struct dma_chan *chan, struct scatterlist *sgl,
sg_dma_len(sg),
value);
if (!desc && first)
- list_splice_init(&first->descs_list,
- &atchan->free_descs_list);
+ list_splice_tail_init(&first->descs_list,
+ &atchan->free_descs_list);
if (!first)
first = desc;
@@ -1709,7 +1712,8 @@ static void at_xdmac_tasklet(struct tasklet_struct *t)
spin_lock_irq(&atchan->lock);
/* Move the xfer descriptors into the free descriptors list. */
- list_splice_init(&desc->descs_list, &atchan->free_descs_list);
+ list_splice_tail_init(&desc->descs_list,
+ &atchan->free_descs_list);
at_xdmac_advance_work(atchan);
spin_unlock_irq(&atchan->lock);
}
@@ -1858,7 +1862,8 @@ static int at_xdmac_device_terminate_all(struct dma_chan *chan)
/* Cancel all pending transfers. */
list_for_each_entry_safe(desc, _desc, &atchan->xfers_list, xfer_node) {
list_del(&desc->xfer_node);
- list_splice_init(&desc->descs_list, &atchan->free_descs_list);
+ list_splice_tail_init(&desc->descs_list,
+ &atchan->free_descs_list);
}
clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
