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-rw-r--r--Documentation/DMA-API.txt2
-rw-r--r--Documentation/IO-mapping.txt4
-rw-r--r--Documentation/block/biodoc.txt5
-rw-r--r--Documentation/usb/dma.txt11
4 files changed, 12 insertions, 10 deletions
diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt
index 52441694fe03..2a3fcc55e981 100644
--- a/Documentation/DMA-API.txt
+++ b/Documentation/DMA-API.txt
@@ -5,7 +5,7 @@
5 5
6This document describes the DMA API. For a more gentle introduction 6This document describes the DMA API. For a more gentle introduction
7phrased in terms of the pci_ equivalents (and actual examples) see 7phrased in terms of the pci_ equivalents (and actual examples) see
8DMA-mapping.txt 8Documentation/PCI/PCI-DMA-mapping.txt.
9 9
10This API is split into two pieces. Part I describes the API and the 10This API is split into two pieces. Part I describes the API and the
11corresponding pci_ API. Part II describes the extensions to the API 11corresponding pci_ API. Part II describes the extensions to the API
diff --git a/Documentation/IO-mapping.txt b/Documentation/IO-mapping.txt
index 86edb61bdee6..78a440695e11 100644
--- a/Documentation/IO-mapping.txt
+++ b/Documentation/IO-mapping.txt
@@ -1,6 +1,6 @@
1[ NOTE: The virt_to_bus() and bus_to_virt() functions have been 1[ NOTE: The virt_to_bus() and bus_to_virt() functions have been
2 superseded by the functionality provided by the PCI DMA 2 superseded by the functionality provided by the PCI DMA interface
3 interface (see Documentation/DMA-mapping.txt). They continue 3 (see Documentation/PCI/PCI-DMA-mapping.txt). They continue
4 to be documented below for historical purposes, but new code 4 to be documented below for historical purposes, but new code
5 must not use them. --davidm 00/12/12 ] 5 must not use them. --davidm 00/12/12 ]
6 6
diff --git a/Documentation/block/biodoc.txt b/Documentation/block/biodoc.txt
index 3c5434c83daf..5d2480d33b43 100644
--- a/Documentation/block/biodoc.txt
+++ b/Documentation/block/biodoc.txt
@@ -186,8 +186,9 @@ a virtual address mapping (unlike the earlier scheme of virtual address
186do not have a corresponding kernel virtual address space mapping) and 186do not have a corresponding kernel virtual address space mapping) and
187low-memory pages. 187low-memory pages.
188 188
189Note: Please refer to DMA-mapping.txt for a discussion on PCI high mem DMA 189Note: Please refer to Documentation/PCI/PCI-DMA-mapping.txt for a discussion
190aspects and mapping of scatter gather lists, and support for 64 bit PCI. 190on PCI high mem DMA aspects and mapping of scatter gather lists, and support
191for 64 bit PCI.
191 192
192Special handling is required only for cases where i/o needs to happen on 193Special handling is required only for cases where i/o needs to happen on
193pages at physical memory addresses beyond what the device can support. In these 194pages at physical memory addresses beyond what the device can support. In these
diff --git a/Documentation/usb/dma.txt b/Documentation/usb/dma.txt
index e8b50b7de9d9..cfdcd16e3abf 100644
--- a/Documentation/usb/dma.txt
+++ b/Documentation/usb/dma.txt
@@ -6,8 +6,9 @@ in the kernel usb programming guide (kerneldoc, from the source code).
6API OVERVIEW 6API 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 DMA-mapping.txt). 9though they still must provide DMA-ready buffers (see
10That's how they've worked through the 2.4 (and earlier) kernels. 10Documentation/PCI/PCI-DMA-mapping.txt). That's how they've worked through
11the 2.4 (and earlier) kernels.
11 12
12OR: they can now be DMA-aware. 13OR: they can now be DMA-aware.
13 14
@@ -62,8 +63,8 @@ and effects like cache-trashing can impose subtle penalties.
62 force a consistent memory access ordering by using memory barriers. It's 63 force a consistent memory access ordering by using memory barriers. It's
63 not using a streaming DMA mapping, so it's good for small transfers on 64 not using a streaming DMA mapping, so it's good for small transfers on
64 systems where the I/O would otherwise thrash an IOMMU mapping. (See 65 systems where the I/O would otherwise thrash an IOMMU mapping. (See
65 Documentation/DMA-mapping.txt for definitions of "coherent" and "streaming" 66 Documentation/PCI/PCI-DMA-mapping.txt for definitions of "coherent" and
66 DMA mappings.) 67 "streaming" DMA mappings.)
67 68
68 Asking for 1/Nth of a page (as well as asking for N pages) is reasonably 69 Asking for 1/Nth of a page (as well as asking for N pages) is reasonably
69 space-efficient. 70 space-efficient.
@@ -93,7 +94,7 @@ WORKING WITH EXISTING BUFFERS
93Existing buffers aren't usable for DMA without first being mapped into the 94Existing buffers aren't usable for DMA without first being mapped into the
94DMA address space of the device. However, most buffers passed to your 95DMA address space of the device. However, most buffers passed to your
95driver can safely be used with such DMA mapping. (See the first section 96driver can safely be used with such DMA mapping. (See the first section
96of DMA-mapping.txt, titled "What memory is DMA-able?") 97of Documentation/PCI/PCI-DMA-mapping.txt, titled "What memory is DMA-able?")
97 98
98- When you're using scatterlists, you can map everything at once. On some 99- When you're using scatterlists, you can map everything at once. On some
99 systems, this kicks in an IOMMU and turns the scatterlists into single 100 systems, this kicks in an IOMMU and turns the scatterlists into single