linux-kernel - [PATCH 1/2] powerpc/iommu: expose IOMMU page shift

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: <20151002171800.GB41011@linux.vnet.ibm.com>
Date:	Fri, 2 Oct 2015 10:18:00 -0700
From:	Nishanth Aravamudan <nacc@...ux.vnet.ibm.com>
To:	Matthew Wilcox <willy@...ux.intel.com>
Cc:	Keith Busch <keith.busch@...el.com>,
	Benjamin Herrenschmidt <benh@...nel.crashing.org>,
	Paul Mackerras <paulus@...ba.org>,
	Michael Ellerman <mpe@...erman.id.au>,
	Alexey Kardashevskiy <aik@...abs.ru>,
	David Gibson <david@...son.dropbear.id.au>,
	linux-nvme@...ts.infradead.org, linux-kernel@...r.kernel.org,
	linuxppc-dev@...ts.ozlabs.org
Subject: [PATCH 1/2] powerpc/iommu: expose IOMMU page shift

We will leverage this macro in the NVMe driver, which needs to know the
configured IOMMU page shift to properly configure its device's page
size.

Signed-off-by: Nishanth Aravamudan <nacc@...ux.vnet.ibm.com>

---
Given this is available, it seems reasonable to expose -- and it doesn't
really make sense to make the driver do a log2 call on the existing
IOMMU_PAGE_SIZE() value.

diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h
index ca18cff..6fdf857 100644
--- a/arch/powerpc/include/asm/iommu.h
+++ b/arch/powerpc/include/asm/iommu.h
@@ -36,6 +36,7 @@
 #define IOMMU_PAGE_MASK_4K       (~((1 << IOMMU_PAGE_SHIFT_4K) - 1))
 #define IOMMU_PAGE_ALIGN_4K(addr) _ALIGN_UP(addr, IOMMU_PAGE_SIZE_4K)
 
+#define IOMMU_PAGE_SHIFT(tblptr) (tblptr)->it_page_shift
 #define IOMMU_PAGE_SIZE(tblptr) (ASM_CONST(1) << (tblptr)->it_page_shift)
 #define IOMMU_PAGE_MASK(tblptr) (~((1 << (tblptr)->it_page_shift) - 1))
 #define IOMMU_PAGE_ALIGN(addr, tblptr) _ALIGN_UP(addr, IOMMU_PAGE_SIZE(tblptr))

--
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/