[PATCH v3 3/6] dma-mapping: Remove dma_check_mask()

Thiago Jung Bauermann
2019-07-18T03:29:46Z

sme_active() is an x86-specific function so it's better not to call it from
generic code. Christoph Hellwig mentioned that "There is no reason why we
should have a special debug printk just for one specific reason why there
is a requirement for a large DMA mask.", so just remove dma_check_mask().

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
---
kernel/dma/mapping.c | 8 --------
1 file changed, 8 deletions(-)

diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index 1f628e7ac709..61eeefbfcb36 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -291,12 +291,6 @@ void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
}
EXPORT_SYMBOL(dma_free_attrs);

-static inline void dma_check_mask(struct device *dev, u64 mask)
-{
- if (sme_active() && (mask < (((u64)sme_get_me_mask() << 1) - 1)))
- dev_warn(dev, "SME is active, device will require DMA bounce buffers\n");
-}
-
int dma_supported(struct device *dev, u64 mask)
{
const struct dma_map_ops *ops = get_dma_ops(dev);
@@ -327,7 +321,6 @@ int dma_set_mask(struct device *dev, u64 mask)
return -EIO;

arch_dma_set_mask(dev, mask);
- dma_check_mask(dev, mask);
*dev->dma_mask = mask;
return 0;
}
@@ -345,7 +338,6 @@ int dma_set_coherent_mask(struct device *dev, u64 mask)
if (!dma_supported(dev, mask))
return -EIO;

- dma_check_mask(dev, mask);
dev->coherent_dma_mask = mask;
return 0;
}