From: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Date: Tue, 14 Jul 2020 14:39:25 +0200
Subject: dma-direct: provide function to check physical memory area validity
Git-commit: 567f6a6eba0c09e5f502e0290e57651befa8aacb
Patch-mainline: v5.8-rc6
References: bsc#1175898, ECO-2743

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>
Acked-by: Joerg Roedel <jroedel@suse.de>
---
 include/linux/dma-direct.h |    1 +
 kernel/dma/direct.c        |    2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

--- a/include/linux/dma-direct.h
+++ b/include/linux/dma-direct.h
@@ -69,6 +69,7 @@ static inline bool dma_capable(struct de
 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,
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -82,7 +82,7 @@ gfp_t dma_direct_optimal_gfp_mask(struct
 	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_limit);