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authorLeon Romanovsky <leonro@nvidia.com>2024-07-24 21:04:48 +0300
committerChristoph Hellwig <hch@lst.de>2024-08-22 06:18:11 +0200
commitf69e342eec008e1bab772d3963c3dd9979293e13 (patch)
treefe81e6278c488ef1a0e7d643ef6b37a073aac722 /kernel
parent3be9b846896d1d8b66040ece6e216cd58d03242e (diff)
dma-mapping: call ->unmap_page and ->unmap_sg unconditionally
Almost all instances of the dma_map_ops ->map_page()/map_sg() methods implement ->unmap_page()/unmap_sg() too. The once instance which doesn't dma_dummy_ops which is used to fail the DMA mapping and thus there won't be any calls to ->unmap_page()/unmap_sg(). Remove the checks for ->unmap_page()/unmap_sg() and call them directly to create an interface that is symmetrical to ->map_page()/map_sg(). Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Leon Romanovsky <leon@kernel.org> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/dma/dummy.c21
-rw-r--r--kernel/dma/mapping.c4
2 files changed, 23 insertions, 2 deletions
diff --git a/kernel/dma/dummy.c b/kernel/dma/dummy.c
index b492d59ac77e..92de80e5b057 100644
--- a/kernel/dma/dummy.c
+++ b/kernel/dma/dummy.c
@@ -17,6 +17,15 @@ static dma_addr_t dma_dummy_map_page(struct device *dev, struct page *page,
{
return DMA_MAPPING_ERROR;
}
+static void dma_dummy_unmap_page(struct device *dev, dma_addr_t dma_handle,
+ size_t size, enum dma_data_direction dir, unsigned long attrs)
+{
+ /*
+ * Dummy ops doesn't support map_page, so unmap_page should never be
+ * called.
+ */
+ WARN_ON_ONCE(true);
+}
static int dma_dummy_map_sg(struct device *dev, struct scatterlist *sgl,
int nelems, enum dma_data_direction dir,
@@ -25,6 +34,16 @@ static int dma_dummy_map_sg(struct device *dev, struct scatterlist *sgl,
return -EINVAL;
}
+static void dma_dummy_unmap_sg(struct device *dev, struct scatterlist *sgl,
+ int nelems, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ /*
+ * Dummy ops doesn't support map_sg, so unmap_sg should never be called.
+ */
+ WARN_ON_ONCE(true);
+}
+
static int dma_dummy_supported(struct device *hwdev, u64 mask)
{
return 0;
@@ -33,6 +52,8 @@ static int dma_dummy_supported(struct device *hwdev, u64 mask)
const struct dma_map_ops dma_dummy_ops = {
.mmap = dma_dummy_mmap,
.map_page = dma_dummy_map_page,
+ .unmap_page = dma_dummy_unmap_page,
.map_sg = dma_dummy_map_sg,
+ .unmap_sg = dma_dummy_unmap_sg,
.dma_supported = dma_dummy_supported,
};
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index b1c18058d55f..71416b156bb5 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -177,7 +177,7 @@ void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr, size_t size,
if (dma_map_direct(dev, ops) ||
arch_dma_unmap_page_direct(dev, addr + size))
dma_direct_unmap_page(dev, addr, size, dir, attrs);
- else if (ops->unmap_page)
+ else
ops->unmap_page(dev, addr, size, dir, attrs);
debug_dma_unmap_page(dev, addr, size, dir);
}
@@ -291,7 +291,7 @@ void dma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
if (dma_map_direct(dev, ops) ||
arch_dma_unmap_sg_direct(dev, sg, nents))
dma_direct_unmap_sg(dev, sg, nents, dir, attrs);
- else if (ops->unmap_sg)
+ else
ops->unmap_sg(dev, sg, nents, dir, attrs);
}
EXPORT_SYMBOL(dma_unmap_sg_attrs);