diff options
Diffstat (limited to 'Documentation')
68 files changed, 2755 insertions, 1647 deletions
diff --git a/Documentation/ABI/removed/raw1394_legacy_isochronous b/Documentation/ABI/removed/raw1394_legacy_isochronous new file mode 100644 index 00000000000..1b629622d88 --- /dev/null +++ b/Documentation/ABI/removed/raw1394_legacy_isochronous @@ -0,0 +1,16 @@ +What: legacy isochronous ABI of raw1394 (1st generation iso ABI) +Date: June 2007 (scheduled), removed in kernel v2.6.23 +Contact: linux1394-devel@lists.sourceforge.net +Description: + The two request types RAW1394_REQ_ISO_SEND, RAW1394_REQ_ISO_LISTEN have + been deprecated for quite some time. They are very inefficient as they + come with high interrupt load and several layers of callbacks for each + packet. Because of these deficiencies, the video1394 and dv1394 drivers + and the 3rd-generation isochronous ABI in raw1394 (rawiso) were created. + +Users: + libraw1394 users via the long deprecated API raw1394_iso_write, + raw1394_start_iso_write, raw1394_start_iso_rcv, raw1394_stop_iso_rcv + + libdc1394, which optionally uses these old libraw1394 calls + alternatively to the more efficient video1394 ABI diff --git a/Documentation/BUG-HUNTING b/Documentation/BUG-HUNTING index 65b97e1dbf7..35f5bd24333 100644 --- a/Documentation/BUG-HUNTING +++ b/Documentation/BUG-HUNTING @@ -191,6 +191,30 @@ e.g. crash dump output as shown by Dave Miller. > mov 0x8(%ebp), %ebx ! %ebx = skb->sk > mov 0x13c(%ebx), %eax ! %eax = inet_sk(sk)->opt +In addition, you can use GDB to figure out the exact file and line +number of the OOPS from the vmlinux file. If you have +CONFIG_DEBUG_INFO enabled, you can simply copy the EIP value from the +OOPS: + + EIP: 0060:[<c021e50e>] Not tainted VLI + +And use GDB to translate that to human-readable form: + + gdb vmlinux + (gdb) l *0xc021e50e + +If you don't have CONFIG_DEBUG_INFO enabled, you use the function +offset from the OOPS: + + EIP is at vt_ioctl+0xda8/0x1482 + +And recompile the kernel with CONFIG_DEBUG_INFO enabled: + + make vmlinux + gdb vmlinux + (gdb) p vt_ioctl + (gdb) l *(0x<address of vt_ioctl> + 0xda8) + Another very useful option of the Kernel Hacking section in menuconfig is Debug memory allocations. This will help you see whether data has been initialised and not set before use etc. To see the values that get assigned diff --git a/Documentation/CodingStyle b/Documentation/CodingStyle index afc28677589..b49b92edb39 100644 --- a/Documentation/CodingStyle +++ b/Documentation/CodingStyle @@ -495,29 +495,40 @@ re-formatting you may want to take a look at the man page. But remember: "indent" is not a fix for bad programming. - Chapter 10: Configuration-files + Chapter 10: Kconfig configuration files -For configuration options (arch/xxx/Kconfig, and all the Kconfig files), -somewhat different indentation is used. +For all of the Kconfig* configuration files throughout the source tree, +the indentation is somewhat different. Lines under a "config" definition +are indented with one tab, while help text is indented an additional two +spaces. Example: -Help text is indented with 2 spaces. - -if CONFIG_EXPERIMENTAL - tristate CONFIG_BOOM - default n - help - Apply nitroglycerine inside the keyboard (DANGEROUS) - bool CONFIG_CHEER - depends on CONFIG_BOOM - default y +config AUDIT + bool "Auditing support" + depends on NET help - Output nice messages when you explode -endif + Enable auditing infrastructure that can be used with another + kernel subsystem, such as SELinux (which requires this for + logging of avc messages output). Does not do system-call + auditing without CONFIG_AUDITSYSCALL. + +Features that might still be considered unstable should be defined as +dependent on "EXPERIMENTAL": + +config SLUB + depends on EXPERIMENTAL && !ARCH_USES_SLAB_PAGE_STRUCT + bool "SLUB (Unqueued Allocator)" + ... + +while seriously dangerous features (such as write support for certain +filesystems) should advertise this prominently in their prompt string: + +config ADFS_FS_RW + bool "ADFS write support (DANGEROUS)" + depends on ADFS_FS + ... -Generally, CONFIG_EXPERIMENTAL should surround all options not considered -stable. All options that are known to trash data (experimental write- -support for file-systems, for instance) should be denoted (DANGEROUS), other -experimental options should be denoted (EXPERIMENTAL). +For full documentation on the configuration files, see the file +Documentation/kbuild/kconfig-language.txt. Chapter 11: Data structures diff --git a/Documentation/DMA-mapping.txt b/Documentation/DMA-mapping.txt index 028614cdd06..e07f2530326 100644 --- a/Documentation/DMA-mapping.txt +++ b/Documentation/DMA-mapping.txt @@ -664,109 +664,6 @@ It is that simple. Well, not for some odd devices. See the next section for information about that. - DAC Addressing for Address Space Hungry Devices - -There exists a class of devices which do not mesh well with the PCI -DMA mapping API. By definition these "mappings" are a finite -resource. The number of total available mappings per bus is platform -specific, but there will always be a reasonable amount. - -What is "reasonable"? Reasonable means that networking and block I/O -devices need not worry about using too many mappings. - -As an example of a problematic device, consider compute cluster cards. -They can potentially need to access gigabytes of memory at once via -DMA. Dynamic mappings are unsuitable for this kind of access pattern. - -To this end we've provided a small API by which a device driver -may use DAC cycles to directly address all of physical memory. -Not all platforms support this, but most do. It is easy to determine -whether the platform will work properly at probe time. - -First, understand that there may be a SEVERE performance penalty for -using these interfaces on some platforms. Therefore, you MUST only -use these interfaces if it is absolutely required. %99 of devices can -use the normal APIs without any problems. - -Note that for streaming type mappings you must either use these -interfaces, or the dynamic mapping interfaces above. You may not mix -usage of both for the same device. Such an act is illegal and is -guaranteed to put a banana in your tailpipe. - -However, consistent mappings may in fact be used in conjunction with -these interfaces. Remember that, as defined, consistent mappings are -always going to be SAC addressable. - -The first thing your driver needs to do is query the PCI platform -layer if it is capable of handling your devices DAC addressing -capabilities: - - int pci_dac_dma_supported(struct pci_dev *hwdev, u64 mask); - -You may not use the following interfaces if this routine fails. - -Next, DMA addresses using this API are kept track of using the -dma64_addr_t type. It is guaranteed to be big enough to hold any -DAC address the platform layer will give to you from the following -routines. If you have consistent mappings as well, you still -use plain dma_addr_t to keep track of those. - -All mappings obtained here will be direct. The mappings are not -translated, and this is the purpose of this dialect of the DMA API. - -All routines work with page/offset pairs. This is the _ONLY_ way to -portably refer to any piece of memory. If you have a cpu pointer -(which may be validly DMA'd too) you may easily obtain the page -and offset using something like this: - - struct page *page = virt_to_page(ptr); - unsigned long offset = offset_in_page(ptr); - -Here are the interfaces: - - dma64_addr_t pci_dac_page_to_dma(struct pci_dev *pdev, - struct page *page, - unsigned long offset, - int direction); - -The DAC address for the tuple PAGE/OFFSET are returned. The direction -argument is the same as for pci_{map,unmap}_single(). The same rules -for cpu/device access apply here as for the streaming mapping -interfaces. To reiterate: - - The cpu may touch the buffer before pci_dac_page_to_dma. - The device may touch the buffer after pci_dac_page_to_dma - is made, but the cpu may NOT. - -When the DMA transfer is complete, invoke: - - void pci_dac_dma_sync_single_for_cpu(struct pci_dev *pdev, - dma64_addr_t dma_addr, - size_t len, int direction); - -This must be done before the CPU looks at the buffer again. -This interface behaves identically to pci_dma_sync_{single,sg}_for_cpu(). - -And likewise, if you wish to let the device get back at the buffer after -the cpu has read/written it, invoke: - - void pci_dac_dma_sync_single_for_device(struct pci_dev *pdev, - dma64_addr_t dma_addr, - size_t len, int direction); - -before letting the device access the DMA area again. - -If you need to get back to the PAGE/OFFSET tuple from a dma64_addr_t -the following interfaces are provided: - - struct page *pci_dac_dma_to_page(struct pci_dev *pdev, - dma64_addr_t dma_addr); - unsigned long pci_dac_dma_to_offset(struct pci_dev *pdev, - dma64_addr_t dma_addr); - -This is possible with the DAC interfaces purely because they are -not translated in any way. - Optimizing Unmap State Space Consumption On many platforms, pci_unmap_{single,page}() is simply a nop. diff --git a/Documentation/DocBook/gadget.tmpl b/Documentation/DocBook/gadget.tmpl index e7fc9643340..6996d977bf8 100644 --- a/Documentation/DocBook/gadget.tmpl +++ b/Documentation/DocBook/gadget.tmpl @@ -52,7 +52,7 @@ <toc></toc> -<chapter><title>Introduction</title> +<chapter id="intro"><title>Introduction</title> <para>This document presents a Linux-USB "Gadget" kernel mode diff --git a/Documentation/DocBook/kernel-api.tmpl b/Documentation/DocBook/kernel-api.tmpl index 38f88b6ae40..46bcff2849b 100644 --- a/Documentation/DocBook/kernel-api.tmpl +++ b/Documentation/DocBook/kernel-api.tmpl @@ -643,4 +643,70 @@ X!Idrivers/video/console/fonts.c !Edrivers/spi/spi.c </chapter> + <chapter id="i2c"> + <title>I<superscript>2</superscript>C and SMBus Subsystem</title> + + <para> + I<superscript>2</superscript>C (or without fancy typography, "I2C") + is an acronym for the "Inter-IC" bus, a simple bus protocol which is + widely used where low data rate communications suffice. + Since it's also a licensed trademark, some vendors use another + name (such as "Two-Wire Interface", TWI) for the same bus. + I2C only needs two signals (SCL for clock, SDA for data), conserving + board real estate and minimizing signal quality issues. + Most I2C devices use seven bit addresses, and bus speeds of up + to 400 kHz; there's a high speed extension (3.4 MHz) that's not yet + found wide use. + I2C is a multi-master bus; open drain signaling is used to + arbitrate between masters, as well as to handshake and to + synchronize clocks from slower clients. + </para> + + <para> + The Linux I2C programming interfaces support only the master + side of bus interactions, not the slave side. + The programming interface is structured around two kinds of driver, + and two kinds of device. + An I2C "Adapter Driver" abstracts the controller hardware; it binds + to a physical device (perhaps a PCI device or platform_device) and + exposes a <structname>struct i2c_adapter</structname> representing + each I2C bus segment it manages. + On each I2C bus segment will be I2C devices represented by a + <structname>struct i2c_client</structname>. Those devices will + be bound to a <structname>struct i2c_driver</structname>, + which should follow the standard Linux driver model. + (At this writing, a legacy model is more widely used.) + There are functions to perform various I2C protocol operations; at + this writing all such functions are usable only from task context. + </para> + + <para> + The System Management Bus (SMBus) is a sibling protocol. Most SMBus + systems are also I2C conformant. The electrical constraints are + tighter for SMBus, and it standardizes particular protocol messages + and idioms. Controllers that support I2C can also support most + SMBus operations, but SMBus controllers don't support all the protocol + options that an I2C controller will. + There are functions to perform various SMBus protocol operations, + either using I2C primitives or by issuing SMBus commands to + i2c_adapter devices which don't support those I2C operations. + </para> + +!Iinclude/linux/i2c.h +!Fdrivers/i2c/i2c-boardinfo.c i2c_register_board_info +!Edrivers/i2c/i2c-core.c + </chapter> + + <chapter id="splice"> + <title>splice API</title> + <para>) + splice is a method for moving blocks of data around inside the + kernel, without continually transferring it between the kernel + and user space. + </para> +!Iinclude/linux/splice.h +!Ffs/splice.c + </chapter> + + </book> diff --git a/Documentation/DocBook/kernel-locking.tmpl b/Documentation/DocBook/kernel-locking.tmpl index 644c3884fab..0a441f73261 100644 --- a/Documentation/DocBook/kernel-locking.tmpl +++ b/Documentation/DocBook/kernel-locking.tmpl @@ -551,10 +551,12 @@ <function>spin_lock_irqsave()</function>, which is a superset of all other spinlock primitives. </para> + <table> <title>Table of Locking Requirements</title> <tgroup cols="11"> <tbody> + <row> <entry></entry> <entry>IRQ Handler A</entry> @@ -576,97 +578,128 @@ <row> <entry>IRQ Handler B</entry> -<entry>spin_lock_irqsave</entry> +<entry>SLIS</entry> <entry>None</entry> </row> <row> <entry>Softirq A</entry> -<entry>spin_lock_irq</entry> -<entry>spin_lock_irq</entry> -<entry>spin_lock</entry> +<entry>SLI</entry> +<entry>SLI</entry> +<entry>SL</entry> </row> <row> <entry>Softirq B</entry> -<entry>spin_lock_irq</entry> -<entry>spin_lock_irq</entry> -<entry>spin_lock</entry> -<entry>spin_lock</entry> +<entry>SLI</entry> +<entry>SLI</entry> +<entry>SL</entry> +<entry>SL</entry> </row> <row> <entry>Tasklet A</entry> -<entry>spin_lock_irq</entry> -<entry>spin_lock_irq</entry> -<entry>spin_lock</entry> -<entry>spin_lock</entry> +<entry>SLI</entry> +<entry>SLI</entry> +<entry>SL</entry> +<entry>SL</entry> <entry>None</entry> </row> <row> <entry>Tasklet B</entry> -<entry>spin_lock_irq</entry> -<entry>spin_lock_irq</entry> -<entry>spin_lock</entry> -<entry>spin_lock</entry> -<entry>spin_lock</entry> +<entry>SLI</entry> +<entry>SLI</entry> +<entry>SL</entry> +<entry>SL</entry> +<entry>SL</entry> <entry>None</entry> </row> <row> <entry>Timer A</entry> -<entry>spin_lock_irq</entry> -<entry>spin_lock_irq</entry> -<entry>spin_lock</entry> -<entry>spin_lock</entry> -<entry>spin_lock</entry> -<entry>spin_lock</entry> +<entry>SLI</entry> +<entry>SLI</entry> +<entry>SL</entry> +<entry>SL</entry> +<entry>SL</entry> +<entry>SL</entry> <entry>None</entry> </row> <row> <entry>Timer B</entry> -<entry>spin_lock_irq</entry> -<entry>spin_lock_irq</entry> -<entry>spin_lock</entry> -<entry>spin_lock</entry> -<entry>spin_lock</entry> -<entry>spin_lock</entry> -<entry>spin_lock</entry> +<entry>SLI</entry> +<entry>SLI</entry> +<entry>SL</entry> +<entry>SL</entry> +<entry>SL</entry> +<entry>SL</entry> +<entry>SL</entry> <entry>None</entry> </row> <row> <entry>User Context A</entry> -<entry>spin_lock_irq</entry> -<entry>spin_lock_irq</entry> -<entry>spin_lock_bh</entry> -<entry>spin_lock_bh</entry> -<entry>spin_lock_bh</entry> -< |