linux-kernel - [PATCH 13/14] common: DMA-mapping: add WRITE

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-id: <1324643253-3024-14-git-send-email-m.szyprowski@samsung.com>
Date:	Fri, 23 Dec 2011 13:27:32 +0100
From:	Marek Szyprowski <m.szyprowski@...sung.com>
To:	linux-kernel@...r.kernel.org
Cc:	Benjamin Herrenschmidt <benh@...nel.crashing.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Arnd Bergmann <arnd@...db.de>,
	Stephen Rothwell <sfr@...b.auug.org.au>,
	microblaze-uclinux@...e.uq.edu.au, linux-arch@...r.kernel.org,
	x86@...nel.org, linux-sh@...r.kernel.org,
	linux-alpha@...r.kernel.org, sparclinux@...r.kernel.org,
	linux-ia64@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org,
	linux-mips@...ux-mips.org, discuss@...-64.org,
	linux-arm-kernel@...ts.infradead.org, linux-mm@...ck.org,
	linaro-mm-sig@...ts.linaro.org, Jonathan Corbet <corbet@....net>,
	Marek Szyprowski <m.szyprowski@...sung.com>,
	Kyungmin Park <kyungmin.park@...sung.com>,
	Andrzej Pietrasiewicz <andrzej.p@...sung.com>
Subject: [PATCH 13/14] common: DMA-mapping: add WRITE_COMBINE attribute

DMA_ATTR_WRITE_COMBINE specifies that writes to the mapping may be
buffered to improve performance. It will be used by the replacement for
ARM/ARV32 specific dma_alloc_writecombine() function.

Signed-off-by: Marek Szyprowski <m.szyprowski@...sung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@...sung.com>
---
 Documentation/DMA-attributes.txt |   10 ++++++++++
 include/linux/dma-attrs.h        |    1 +
 2 files changed, 11 insertions(+), 0 deletions(-)

diff --git a/Documentation/DMA-attributes.txt b/Documentation/DMA-attributes.txt
index b768cc0..811a5d4 100644
--- a/Documentation/DMA-attributes.txt
+++ b/Documentation/DMA-attributes.txt
@@ -31,3 +31,13 @@ may be weakly ordered, that is that reads and writes may pass each other.
 Since it is optional for platforms to implement DMA_ATTR_WEAK_ORDERING,
 those that do not will simply ignore the attribute and exhibit default
 behavior.
+
+DMA_ATTR_WRITE_COMBINE
+----------------------
+
+DMA_ATTR_WRITE_COMBINE specifies that writes to the mapping may be
+buffered to improve performance.
+
+Since it is optional for platforms to implement DMA_ATTR_WRITE_COMBINE,
+those that do not will simply ignore the attribute and exhibit default
+behavior.
diff --git a/include/linux/dma-attrs.h b/include/linux/dma-attrs.h
index 71ad34e..ada61e1 100644
--- a/include/linux/dma-attrs.h
+++ b/include/linux/dma-attrs.h
@@ -13,6 +13,7 @@
 enum dma_attr {
 	DMA_ATTR_WRITE_BARRIER,
 	DMA_ATTR_WEAK_ORDERING,
+	DMA_ATTR_WRITE_COMBINE,
 	DMA_ATTR_MAX,
 };
 
-- 
1.7.1.569.g6f426

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/