diff mbox series

[24/30,for,5.4] dma-direct: provide function to check physical memory area validity

Message ID 20200925161916.204667-25-pgonda@google.com
State New
Headers show
Series Backport unencrypted non-blocking DMA allocations | expand

Commit Message

Peter Gonda Sept. 25, 2020, 4:19 p.m. UTC
From: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>

upstream 567f6a6eba0c09e5f502e0290e57651befa8aacb commit.

dma_coherent_ok() checks if a physical memory area fits a device's DMA
constraints.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Peter Gonda <pgonda@google.com>
---
 include/linux/dma-direct.h | 1 +
 kernel/dma/direct.c        | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h
index fb5ec847ddf3..8ccddee1f78a 100644
--- a/include/linux/dma-direct.h
+++ b/include/linux/dma-direct.h
@@ -68,6 +68,7 @@  static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
 u64 dma_direct_get_required_mask(struct device *dev);
 gfp_t dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask,
 				  u64 *phys_mask);
+bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size);
 void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
 		gfp_t gfp, unsigned long attrs);
 void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 6c677ffdbd53..54c1c3a20c09 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -84,7 +84,7 @@  gfp_t dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask,
 	return 0;
 }
 
-static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
+bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
 {
 	return phys_to_dma_direct(dev, phys) + size - 1 <=
 			min_not_zero(dev->coherent_dma_mask, dev->bus_dma_mask);