diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/DMA-API.txt | 2 | ||||
| -rw-r--r-- | Documentation/IO-mapping.txt | 4 | ||||
| -rw-r--r-- | Documentation/block/biodoc.txt | 5 | ||||
| -rw-r--r-- | Documentation/usb/dma.txt | 11 |
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 @@ This document describes the DMA API. For a more gentle introduction phrased in terms of the pci_ equivalents (and actual examples) see -DMA-mapping.txt +Documentation/PCI/PCI-DMA-mapping.txt. This API is split into two pieces. Part I describes the API and the corresponding 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+++ b/Documentation/IO-mapping.txt @@ -1,6 +1,6 @@ [ NOTE: The virt_to_bus() and bus_to_virt() functions have been - superseded by the functionality provided by the PCI DMA - interface (see Documentation/DMA-mapping.txt). They continue + superseded by the functionality provided by the PCI DMA interface + (see Documentation/PCI/PCI-DMA-mapping.txt). They continue to be documented below for historical purposes, but new code must not use them. --davidm 00/12/12 ] 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 do not have a corresponding kernel virtual address space mapping) and low-memory pages. -Note: Please refer to DMA-mapping.txt for a discussion on PCI high mem DMA -aspects and mapping of scatter gather lists, and support for 64 bit PCI. +Note: Please refer to Documentation/PCI/PCI-DMA-mapping.txt for a discussion +on PCI high mem DMA aspects and mapping of scatter gather lists, and support +for 64 bit PCI. Special handling is required only for cases where i/o needs to happen on pages 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). API OVERVIEW The big picture is that USB drivers can continue to ignore most DMA issues, -though they still must provide DMA-ready buffers (see DMA-mapping.txt). -That's how they've worked through the 2.4 (and earlier) kernels. +though they still must provide DMA-ready buffers (see +Documentation/PCI/PCI-DMA-mapping.txt). That's how they've worked through +the 2.4 (and earlier) kernels. OR: they can now be DMA-aware. @@ -62,8 +63,8 @@ and effects like cache-trashing can impose subtle penalties. force a consistent memory access ordering by using memory barriers. It's not using a streaming DMA mapping, so it's good for small transfers on systems where the I/O would otherwise thrash an IOMMU mapping. (See - Documentation/DMA-mapping.txt for definitions of "coherent" and "streaming" - DMA mappings.) + Documentation/PCI/PCI-DMA-mapping.txt for definitions of "coherent" and + "streaming" DMA mappings.) Asking for 1/Nth of a page (as well as asking for N pages) is reasonably space-efficient. @@ -93,7 +94,7 @@ WORKING WITH EXISTING BUFFERS Existing buffers aren't usable for DMA without first being mapped into the DMA address space of the device. However, most buffers passed to your driver can safely be used with such DMA mapping. (See the first section -of DMA-mapping.txt, titled "What memory is DMA-able?") +of Documentation/PCI/PCI-DMA-mapping.txt, titled "What memory is DMA-able?") - When you're using scatterlists, you can map everything at once. On some systems, this kicks in an IOMMU and turns the scatterlists into single |