[PATCH 23/23] dma-mapping: return an error code from dma_mapping_error

From: Christoph Hellwig <hch@lst.de>
To: iommu@lists.linux-foundation.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	Jon Mason <jdmason@kudzu.us>, Joerg Roedel <joro@8bytes.org>,
	David Woodhouse <dwmw2@infradead.org>,
	Marek Szyprowski <m.szyprowski@samsung.com>,
	Robin Murphy <robin.murphy@arm.com>,
	x86@kernel.org, linux-alpha@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org,
	linux-parisc@vger.kernel.org, xen-devel@lists.xenproject.org,
	linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH 23/23] dma-mapping: return an error code from dma_mapping_error
Date: Fri, 30 Nov 2018 14:22:31 +0100	[thread overview]
Message-ID: <20181130132231.16512-24-hch@lst.de> (raw)
In-Reply-To: <20181130132231.16512-1-hch@lst.de>

Currently dma_mapping_error returns a boolean as int, with 1 meaning
error.  This is rather unusual and many callers have to convert it to
errno value.  The callers are highly inconsistent with error codes
ranging from -ENOMEM over -EIO, -EINVAL and -EFAULT ranging to -EAGAIN.
Return -ENOMEM which seems to be what the largest number of callers
convert it to, and which also matches the typical error case where
we are out of resources.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 include/linux/dma-mapping.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 2adef56c6069..b5bd25fc1f81 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -576,7 +576,7 @@ static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 {
 	debug_dma_mapping_error(dev, dma_addr);
 	if (dma_addr == DMA_MAPPING_ERROR)
-		return 1;
+		return -ENOMEM;
 	return 0;
 }
 
-- 
2.19.1

