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authorLinus Torvalds <torvalds@linux-foundation.org>2012-12-20 22:07:25 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2012-12-20 22:07:25 +0400
commit787314c35fbb97e02823a1b8eb8cfa58f366cd49 (patch)
tree3fe5a484c1846c80361217a726997484533e8344 /Documentation/DMA-API.txt
parent6491d4d02893d9787ba67279595990217177b351 (diff)
parent9c6ecf6a3ade2dc4b03a239af68058b22897af41 (diff)
downloadlinux-787314c35fbb97e02823a1b8eb8cfa58f366cd49.tar.xz
Merge tag 'iommu-updates-v3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU updates from Joerg Roedel: "A few new features this merge-window. The most important one is probably, that dma-debug now warns if a dma-handle is not checked with dma_mapping_error by the device driver. This requires minor changes to some architectures which make use of dma-debug. Most of these changes have the respective Acks by the Arch-Maintainers. Besides that there are updates to the AMD IOMMU driver for refactor the IOMMU-Groups support and to make sure it does not trigger a hardware erratum. The OMAP changes (for which I pulled in a branch from Tony Lindgren's tree) have a conflict in linux-next with the arm-soc tree. The conflict is in the file arch/arm/mach-omap2/clock44xx_data.c which is deleted in the arm-soc tree. It is safe to delete the file too so solve the conflict. Similar changes are done in the arm-soc tree in the common clock framework migration. A missing hunk from the patch in the IOMMU tree will be submitted as a seperate patch when the merge-window is closed." * tag 'iommu-updates-v3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (29 commits) ARM: dma-mapping: support debug_dma_mapping_error ARM: OMAP4: hwmod data: ipu and dsp to use parent clocks instead of leaf clocks iommu/omap: Adapt to runtime pm iommu/omap: Migrate to hwmod framework iommu/omap: Keep mmu enabled when requested iommu/omap: Remove redundant clock handling on ISR iommu/amd: Remove obsolete comment iommu/amd: Don't use 512GB pages iommu/tegra: smmu: Move bus_set_iommu after probe for multi arch iommu/tegra: gart: Move bus_set_iommu after probe for multi arch iommu/tegra: smmu: Remove unnecessary PTC/TLB flush all tile: dma_debug: add debug_dma_mapping_error support sh: dma_debug: add debug_dma_mapping_error support powerpc: dma_debug: add debug_dma_mapping_error support mips: dma_debug: add debug_dma_mapping_error support microblaze: dma-mapping: support debug_dma_mapping_error ia64: dma_debug: add debug_dma_mapping_error support c6x: dma_debug: add debug_dma_mapping_error support ARM64: dma_debug: add debug_dma_mapping_error support intel-iommu: Prevent devices with RMRRs from being placed into SI Domain ...
Diffstat (limited to 'Documentation/DMA-API.txt')
-rw-r--r--Documentation/DMA-API.txt12
1 files changed, 12 insertions, 0 deletions
diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt
index 66bd97a95f10..78a6c569d204 100644
--- a/Documentation/DMA-API.txt
+++ b/Documentation/DMA-API.txt
@@ -678,3 +678,15 @@ out of dma_debug_entries. These entries are preallocated at boot. The number
of preallocated entries is defined per architecture. If it is too low for you
boot with 'dma_debug_entries=<your_desired_number>' to overwrite the
architectural default.
+
+void debug_dmap_mapping_error(struct device *dev, dma_addr_t dma_addr);
+
+dma-debug interface debug_dma_mapping_error() to debug drivers that fail
+to check dma mapping errors on addresses returned by dma_map_single() and
+dma_map_page() interfaces. This interface clears a flag set by
+debug_dma_map_page() to indicate that dma_mapping_error() has been called by
+the driver. When driver does unmap, debug_dma_unmap() checks the flag and if
+this flag is still set, prints warning message that includes call trace that
+leads up to the unmap. This interface can be called from dma_mapping_error()
+routines to enable dma mapping error check debugging.
+