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-rw-r--r--Documentation/usb/dma.txt6
1 files changed, 3 insertions, 3 deletions
diff --git a/Documentation/usb/dma.txt b/Documentation/usb/dma.txt
index 84ef865237d..444651e70d9 100644
--- a/Documentation/usb/dma.txt
+++ b/Documentation/usb/dma.txt
@@ -7,7 +7,7 @@ API OVERVIEW
7 7
8The big picture is that USB drivers can continue to ignore most DMA issues, 8The big picture is that USB drivers can continue to ignore most DMA issues,
9though they still must provide DMA-ready buffers (see 9though they still must provide DMA-ready buffers (see
10Documentation/PCI/PCI-DMA-mapping.txt). That's how they've worked through 10Documentation/DMA-API-HOWTO.txt). That's how they've worked through
11the 2.4 (and earlier) kernels. 11the 2.4 (and earlier) kernels.
12 12
13OR: they can now be DMA-aware. 13OR: they can now be DMA-aware.
@@ -57,7 +57,7 @@ and effects like cache-trashing can impose subtle penalties.
57 force a consistent memory access ordering by using memory barriers. It's 57 force a consistent memory access ordering by using memory barriers. It's
58 not using a streaming DMA mapping, so it's good for small transfers on 58 not using a streaming DMA mapping, so it's good for small transfers on
59 systems where the I/O would otherwise thrash an IOMMU mapping. (See 59 systems where the I/O would otherwise thrash an IOMMU mapping. (See
60 Documentation/PCI/PCI-DMA-mapping.txt for definitions of "coherent" and 60 Documentation/DMA-API-HOWTO.txt for definitions of "coherent" and
61 "streaming" DMA mappings.) 61 "streaming" DMA mappings.)
62 62
63 Asking for 1/Nth of a page (as well as asking for N pages) is reasonably 63 Asking for 1/Nth of a page (as well as asking for N pages) is reasonably
@@ -88,7 +88,7 @@ WORKING WITH EXISTING BUFFERS
88Existing buffers aren't usable for DMA without first being mapped into the 88Existing buffers aren't usable for DMA without first being mapped into the
89DMA address space of the device. However, most buffers passed to your 89DMA address space of the device. However, most buffers passed to your
90driver can safely be used with such DMA mapping. (See the first section 90driver can safely be used with such DMA mapping. (See the first section
91of Documentation/PCI/PCI-DMA-mapping.txt, titled "What memory is DMA-able?") 91of Documentation/DMA-API-HOWTO.txt, titled "What memory is DMA-able?")
92 92
93- When you're using scatterlists, you can map everything at once. On some 93- When you're using scatterlists, you can map everything at once. On some
94 systems, this kicks in an IOMMU and turns the scatterlists into single 94 systems, this kicks in an IOMMU and turns the scatterlists into single