diff options
author | Steven Whitehouse <swhiteho@redhat.com> | 2006-09-28 08:29:59 -0400 |
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committer | Steven Whitehouse <swhiteho@redhat.com> | 2006-09-28 08:29:59 -0400 |
commit | 185a257f2f73bcd89050ad02da5bedbc28fc43fa (patch) | |
tree | 5e32586114534ed3f2165614cba3d578f5d87307 /Documentation | |
parent | 3f1a9aaeffd8d1cbc5ab9776c45cbd66af1c9699 (diff) | |
parent | a77c64c1a641950626181b4857abb701d8f38ccc (diff) |
Merge branch 'master' into gfs2
Diffstat (limited to 'Documentation')
24 files changed, 1383 insertions, 368 deletions
diff --git a/Documentation/ABI/obsolete/devfs b/Documentation/ABI/removed/devfs index b8b87399bc8..8195c4e0d0a 100644 --- a/Documentation/ABI/obsolete/devfs +++ b/Documentation/ABI/removed/devfs @@ -1,13 +1,12 @@ What: devfs -Date: July 2005 +Date: July 2005 (scheduled), finally removed in kernel v2.6.18 Contact: Greg Kroah-Hartman <gregkh@suse.de> Description: devfs has been unmaintained for a number of years, has unfixable races, contains a naming policy within the kernel that is against the LSB, and can be replaced by using udev. - The files fs/devfs/*, include/linux/devfs_fs*.h will be removed, + The files fs/devfs/*, include/linux/devfs_fs*.h were removed, along with the the assorted devfs function calls throughout the kernel tree. Users: - diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power new file mode 100644 index 00000000000..d882f809387 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-power @@ -0,0 +1,88 @@ +What: /sys/power/ +Date: August 2006 +Contact: Rafael J. Wysocki <rjw@sisk.pl> +Description: + The /sys/power directory will contain files that will + provide a unified interface to the power management + subsystem. + +What: /sys/power/state +Date: August 2006 +Contact: Rafael J. Wysocki <rjw@sisk.pl> +Description: + The /sys/power/state file controls the system power state. + Reading from this file returns what states are supported, + which is hard-coded to 'standby' (Power-On Suspend), 'mem' + (Suspend-to-RAM), and 'disk' (Suspend-to-Disk). + + Writing to this file one of these strings causes the system to + transition into that state. Please see the file + Documentation/power/states.txt for a description of each of + these states. + +What: /sys/power/disk +Date: August 2006 +Contact: Rafael J. Wysocki <rjw@sisk.pl> +Description: + The /sys/power/disk file controls the operating mode of the + suspend-to-disk mechanism. Reading from this file returns + the name of the method by which the system will be put to + sleep on the next suspend. There are four methods supported: + 'firmware' - means that the memory image will be saved to disk + by some firmware, in which case we also assume that the + firmware will handle the system suspend. + 'platform' - the memory image will be saved by the kernel and + the system will be put to sleep by the platform driver (e.g. + ACPI or other PM registers). + 'shutdown' - the memory image will be saved by the kernel and + the system will be powered off. + 'reboot' - the memory image will be saved by the kernel and + the system will be rebooted. + + The suspend-to-disk method may be chosen by writing to this + file one of the accepted strings: + + 'firmware' + 'platform' + 'shutdown' + 'reboot' + + It will only change to 'firmware' or 'platform' if the system + supports that. + +What: /sys/power/image_size +Date: August 2006 +Contact: Rafael J. Wysocki <rjw@sisk.pl> +Description: + The /sys/power/image_size file controls the size of the image + created by the suspend-to-disk mechanism. It can be written a + string representing a non-negative integer that will be used + as an upper limit of the image size, in bytes. The kernel's + suspend-to-disk code will do its best to ensure the image size + will not exceed this number. However, if it turns out to be + impossible, the kernel will try to suspend anyway using the + smallest image possible. In particular, if "0" is written to + this file, the suspend image will be as small as possible. + + Reading from this file will display the current image size + limit, which is set to 500 MB by default. + +What: /sys/power/pm_trace +Date: August 2006 +Contact: Rafael J. Wysocki <rjw@sisk.pl> +Description: + The /sys/power/pm_trace file controls the code which saves the + last PM event point in the RTC across reboots, so that you can + debug a machine that just hangs during suspend (or more + commonly, during resume). Namely, the RTC is only used to save + the last PM event point if this file contains '1'. Initially + it contains '0' which may be changed to '1' by writing a + string representing a nonzero integer into it. + + To use this debugging feature you should attempt to suspend + the machine, then reboot it and run + + dmesg -s 1000000 | grep 'hash matches' + + CAUTION: Using it will cause your machine's real-time (CMOS) + clock to be set to a random invalid time after a resume. diff --git a/Documentation/DocBook/usb.tmpl b/Documentation/DocBook/usb.tmpl index 320af25de3a..3608472d7b7 100644 --- a/Documentation/DocBook/usb.tmpl +++ b/Documentation/DocBook/usb.tmpl @@ -43,59 +43,52 @@ <para>A Universal Serial Bus (USB) is used to connect a host, such as a PC or workstation, to a number of peripheral - devices. USB uses a tree structure, with the host at the + devices. USB uses a tree structure, with the host as the root (the system's master), hubs as interior nodes, and - peripheral devices as leaves (and slaves). + peripherals as leaves (and slaves). Modern PCs support several such trees of USB devices, usually one USB 2.0 tree (480 Mbit/sec each) with a few USB 1.1 trees (12 Mbit/sec each) that are used when you connect a USB 1.1 device directly to the machine's "root hub". </para> - <para>That master/slave asymmetry was designed in part for - ease of use. It is not physically possible to assemble - (legal) USB cables incorrectly: all upstream "to-the-host" - connectors are the rectangular type, matching the sockets on - root hubs, and the downstream type are the squarish type - (or they are built in to the peripheral). - Software doesn't need to deal with distributed autoconfiguration - since the pre-designated master node manages all that. - At the electrical level, bus protocol overhead is reduced by - eliminating arbitration and moving scheduling into host software. + <para>That master/slave asymmetry was designed-in for a number of + reasons, one being ease of use. It is not physically possible to + assemble (legal) USB cables incorrectly: all upstream "to the host" + connectors are the rectangular type (matching the sockets on + root hubs), and all downstream connectors are the squarish type + (or they are built into the peripheral). + Also, the host software doesn't need to deal with distributed + auto-configuration since the pre-designated master node manages all that. + And finally, at the electrical level, bus protocol overhead is reduced by + eliminating arbitration and moving scheduling into the host software. </para> - <para>USB 1.0 was announced in January 1996, and was revised + <para>USB 1.0 was announced in January 1996 and was revised as USB 1.1 (with improvements in hub specification and support for interrupt-out transfers) in September 1998. - USB 2.0 was released in April 2000, including high speed - transfers and transaction translating hubs (used for USB 1.1 + USB 2.0 was released in April 2000, adding high-speed + transfers and transaction-translating hubs (used for USB 1.1 and 1.0 backward compatibility). </para> - <para>USB support was added to Linux early in the 2.2 kernel series - shortly before the 2.3 development forked off. Updates - from 2.3 were regularly folded back into 2.2 releases, bringing - new features such as <filename>/sbin/hotplug</filename> support, - more drivers, and more robustness. - The 2.5 kernel series continued such improvements, and also - worked on USB 2.0 support, - higher performance, - better consistency between host controller drivers, - API simplification (to make bugs less likely), - and providing internal "kerneldoc" documentation. + <para>Kernel developers added USB support to Linux early in the 2.2 kernel + series, shortly before 2.3 development forked. Updates from 2.3 were + regularly folded back into 2.2 releases, which improved reliability and + brought <filename>/sbin/hotplug</filename> support as well more drivers. + Such improvements were continued in the 2.5 kernel series, where they added + USB 2.0 support, improved performance, and made the host controller drivers + (HCDs) more consistent. They also simplified the API (to make bugs less + likely) and added internal "kerneldoc" documentation. </para> <para>Linux can run inside USB devices as well as on the hosts that control the devices. - Because the Linux 2.x USB support evolved to support mass market - platforms such as Apple Macintosh or PC-compatible systems, - it didn't address design concerns for those types of USB systems. - So it can't be used inside mass-market PDAs, or other peripherals. - USB device drivers running inside those Linux peripherals + But USB device drivers running inside those peripherals don't do the same things as the ones running inside hosts, - and so they've been given a different name: - they're called <emphasis>gadget drivers</emphasis>. - This document does not present gadget drivers. + so they've been given a different name: + <emphasis>gadget drivers</emphasis>. + This document does not cover gadget drivers. </para> </chapter> @@ -103,17 +96,14 @@ <chapter id="host"> <title>USB Host-Side API Model</title> - <para>Within the kernel, - host-side drivers for USB devices talk to the "usbcore" APIs. - There are two types of public "usbcore" APIs, targetted at two different - layers of USB driver. Those are - <emphasis>general purpose</emphasis> drivers, exposed through - driver frameworks such as block, character, or network devices; - and drivers that are <emphasis>part of the core</emphasis>, - which are involved in managing a USB bus. - Such core drivers include the <emphasis>hub</emphasis> driver, - which manages trees of USB devices, and several different kinds - of <emphasis>host controller driver (HCD)</emphasis>, + <para>Host-side drivers for USB devices talk to the "usbcore" APIs. + There are two. One is intended for + <emphasis>general-purpose</emphasis> drivers (exposed through + driver frameworks), and the other is for drivers that are + <emphasis>part of the core</emphasis>. + Such core drivers include the <emphasis>hub</emphasis> driver + (which manages trees of USB devices) and several different kinds + of <emphasis>host controller drivers</emphasis>, which control individual busses. </para> @@ -122,21 +112,21 @@ <itemizedlist> - <listitem><para>USB supports four kinds of data transfer - (control, bulk, interrupt, and isochronous). Two transfer - types use bandwidth as it's available (control and bulk), - while the other two types of transfer (interrupt and isochronous) + <listitem><para>USB supports four kinds of data transfers + (control, bulk, interrupt, and isochronous). Two of them (control + and bulk) use bandwidth as it's available, + while the other two (interrupt and isochronous) are scheduled to provide guaranteed bandwidth. </para></listitem> <listitem><para>The device description model includes one or more "configurations" per device, only one of which is active at a time. - Devices that are capable of high speed operation must also support - full speed configurations, along with a way to ask about the - "other speed" configurations that might be used. + Devices that are capable of high-speed operation must also support + full-speed configurations, along with a way to ask about the + "other speed" configurations which might be used. </para></listitem> - <listitem><para>Configurations have one or more "interface", each + <listitem><para>Configurations have one or more "interfaces", each of which may have "alternate settings". Interfaces may be standardized by USB "Class" specifications, or may be specific to a vendor or device.</para> @@ -162,7 +152,7 @@ </para></listitem> <listitem><para>The Linux USB API supports synchronous calls for - control and bulk messaging. + control and bulk messages. It also supports asynchnous calls for all kinds of data transfer, using request structures called "URBs" (USB Request Blocks). </para></listitem> @@ -463,14 +453,25 @@ file in your Linux kernel sources. </para> - <para>Otherwise the main use for this file from programs - is to poll() it to get notifications of usb devices - as they're plugged or unplugged. - To see what changed, you'd need to read the file and - compare "before" and "after" contents, scan the filesystem, - or see its hotplug event. + <para>This file, in combination with the poll() system call, can + also be used to detect when devices are added or removed: +<programlisting>int fd; +struct pollfd pfd; + +fd = open("/proc/bus/usb/devices", O_RDONLY); +pfd = { fd, POLLIN, 0 }; +for (;;) { + /* The first time through, this call will return immediately. */ + poll(&pfd, 1, -1); + + /* To see what's changed, compare the file's previous and current + contents or scan the filesystem. (Scanning is more precise.) */ +}</programlisting> + Note that this behavior is intended to be used for informational + and debug purposes. It would be more appropriate to use programs + such as udev or HAL to initialize a device or start a user-mode + helper program, for instance. </para> - </sect1> <sect1> diff --git a/Documentation/HOWTO b/Documentation/HOWTO index 915ae8c986c..1d6560413cc 100644 --- a/Documentation/HOWTO +++ b/Documentation/HOWTO @@ -358,7 +358,8 @@ Here is a list of some of the different kernel trees available: quilt trees: - USB, PCI, Driver Core, and I2C, Greg Kroah-Hartman <gregkh@suse.de> kernel.org/pub/linux/kernel/people/gregkh/gregkh-2.6/ - + - x86-64, partly i386, Andi Kleen <ak@suse.de> + ftp.firstfloor.org:/pub/ak/x86_64/quilt/ Bug Reporting ------------- diff --git a/Documentation/devices.txt b/Documentation/devices.txt index 66c725f530f..addc67b1d77 100644 --- a/Documentation/devices.txt +++ b/Documentation/devices.txt @@ -2543,6 +2543,9 @@ Your cooperation is appreciated. 64 = /dev/usb/rio500 Diamond Rio 500 65 = /dev/usb/usblcd USBLCD Interface (info@usblcd.de) 66 = /dev/usb/cpad0 Synaptics cPad (mouse/LCD) + 67 = /dev/usb/adutux0 1st Ontrak ADU device + ... + 76 = /dev/usb/adutux10 10th Ontrak ADU device 96 = /dev/usb/hiddev0 1st USB HID device ... 111 = /dev/usb/hiddev15 16th USB HID device diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 552507fe9a7..436697cb938 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -6,6 +6,21 @@ be removed from this file. --------------------------- +What: /sys/devices/.../power/state + dev->power.power_state + dpm_runtime_{suspend,resume)() +When: July 2007 +Why: Broken design for runtime control over driver power states, confusing + driver-internal runtime power management with: mechanisms to support + system-wide sleep state transitions; event codes that distinguish + different phases of swsusp "sleep" transitions; and userspace policy + inputs. This framework was never widely used, and most attempts to + use it were broken. Drivers should instead be exposing domain-specific + interfaces either to kernel or to userspace. +Who: Pavel Machek <pavel@suse.cz> + +--------------------------- + What: RAW driver (CONFIG_RAW_DRIVER) When: December 2005 Why: declared obsolete since kernel 2.6.3 @@ -55,6 +70,18 @@ Who: Mauro Carvalho Chehab <mchehab@brturbo.com.br> --------------------------- +What: sys_sysctl +When: January 2007 +Why: The same information is available through /proc/sys and that is the + interface user space prefers to use. And there do not appear to be + any existing user in user space of sys_sysctl. The additional + maintenance overhead of keeping a set of binary names gets + in the way of doing a good job of maintaining this interface. + +Who: Eric Biederman <ebiederm@xmission.com> + +--------------------------- + What: PCMCIA control ioctl (needed for pcmcia-cs [cardmgr, cardctl]) When: November 2005 Files: drivers/pcmcia/: pcmcia_ioctl.c @@ -202,14 +229,6 @@ Who: Nick Piggin <npiggin@suse.de> --------------------------- -What: Support for the MIPS EV96100 evaluation board -When: September 2006 -Why: Does no longer build since at least November 15, 2003, apparently - no userbase left. -Who: Ralf Baechle <ralf@linux-mips.org> - ---------------------------- - What: Support for the Momentum / PMC-Sierra Jaguar ATX evaluation board When: September 2006 Why: Does no longer build since quite some time, and was never popular, @@ -294,3 +313,24 @@ Why: The frame diverter is included in most distribution kernels, but is It is not clear if anyone is still using it. Who: Stephen Hemminger <shemminger@osdl.org> +--------------------------- + + +What: PHYSDEVPATH, PHYSDEVBUS, PHYSDEVDRIVER in the uevent environment +When: Oktober 2008 +Why: The stacking of class devices makes these values misleading and + inconsistent. + Class devices should not carry any of these properties, and bus + devices have SUBSYTEM and DRIVER as a replacement. +Who: Kay Sievers <kay.sievers@suse.de> + +--------------------------- + +What: i2c-isa +When: December 2006 +Why: i2c-isa is a non-sense and doesn't fit in the device driver + model. Drivers relying on it are better implemented as platform + drivers. +Who: Jean Delvare <khali@linux-fr.org> + +--------------------------- diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 99902ae6804..7db71d6fba8 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -1124,11 +1124,15 @@ debugging information is displayed on console. NMI switch that most IA32 servers have fires unknown NMI up, for example. If a system hangs up, try pressing the NMI switch. -[NOTE] - This function and oprofile share a NMI callback. Therefore this function - cannot be enabled when oprofile is activated. - And NMI watchdog will be disabled when the value in this file is set to - non-zero. +nmi_watchdog +------------ + +Enables/Disables the NMI watchdog on x86 systems. When the value is non-zero +the NMI watchdog is enabled and will continuously test all online cpus to +determine whether or not they are still functioning properly. + +Because the NMI watchdog shares registers with oprofile, by disabling the NMI +watchdog, oprofile may have more registers to utilize. 2.4 /proc/sys/vm - The virtual memory subsystem diff --git a/Documentation/i2c/busses/i2c-viapro b/Documentation/i2c/busses/i2c-viapro index 16775663b9f..25680346e0a 100644 --- a/Documentation/i2c/busses/i2c-viapro +++ b/Documentation/i2c/busses/i2c-viapro @@ -7,9 +7,12 @@ Supported adapters: * VIA Technologies, Inc. VT82C686A/B Datasheet: Sometimes available at the VIA website - * VIA Technologies, Inc. VT8231, VT8233, VT8233A, VT8235, VT8237R + * VIA Technologies, Inc. VT8231, VT8233, VT8233A Datasheet: available on request from VIA + * VIA Technologies, Inc. VT8235, VT8237R, VT8237A, VT8251 + Datasheet: available on request and under NDA from VIA + Authors: Kyösti Mälkki <kmalkki@cc.hut.fi>, Mark D. Studebaker <mdsxyz123@yahoo.com>, @@ -39,6 +42,8 @@ Your lspci -n listing must show one of these : device 1106:8235 (VT8231 function 4) device 1106:3177 (VT8235) device 1106:3227 (VT8237R) + device 1106:3337 (VT8237A) + device 1106:3287 (VT8251) If none of these show up, you should look in the BIOS for settings like enable ACPI / SMBus or even USB. diff --git a/Documentation/i2c/i2c-stub b/Documentation/i2c/i2c-stub index d6dcb138abf..9cc081e6976 100644 --- a/Documentation/i2c/i2c-stub +++ b/Documentation/i2c/i2c-stub @@ -6,9 +6,12 @@ This module is a very simple fake I2C/SMBus driver. It implements four types of SMBus commands: write quick, (r/w) byte, (r/w) byte data, and (r/w) word data. +You need to provide a chip address as a module parameter when loading +this driver, which will then only react to SMBus commands to this address. + No hardware is needed nor associated with this module. It will accept write -quick commands to all addresses; it will respond to the other commands (also -to all addresses) by reading from or writing to an array in memory. It will +quick commands to one address; it will respond to the other commands (also +to one address) by reading from or writing to an array in memory. It will also spam the kernel logs for every command it handles. A pointer register with auto-increment is implemented for all byte @@ -21,6 +24,11 @@ The typical use-case is like this: 3. load the target sensors chip driver module 4. observe its behavior in the kernel log +PARAMETERS: + +int chip_addr: + The SMBus address to emulate a chip at. + CAVEATS: There are independent arrays for byte/data and word/data commands. Depending @@ -33,6 +41,9 @@ If the hardware for your driver has banked registers (e.g. Winbond sensors chips) this module will not work well - although it could be extended to support that pretty easily. +Only one chip address is supported - although this module could be +extended to support more. + If you spam it hard enough, printk can be lossy. This module really wants something like relayfs. diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt index b7d6abb501a..e2cbd59cf2d 100644 --- a/Documentation/kbuild/makefiles.txt +++ b/Documentation/kbuild/makefiles.txt @@ -421,6 +421,11 @@ more details, with real examples. The second argument is optional, and if supplied will be used if first argument is not supported. + as-instr + as-instr checks if the assembler reports a specific instruction + and then outputs either option1 or option2 + C escapes are supported in the test instruction + cc-option cc-option is used to check if $(CC) supports a given option, and not supported to use an optional second option. diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 71d05f48172..54983246930 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -573,8 +573,6 @@ running once the system is up. gscd= [HW,CD] Format: <io> - gt96100eth= [NET] MIPS GT96100 Advanced Communication Controller - gus= [HW,OSS] Format: <io>,<irq>,<dma>,<dma16> @@ -1240,7 +1238,11 @@ running once the system is up. bootloader. This is currently used on IXP2000 systems where the bus has to be configured a certain way for adjunct CPUs. - + noearly [X86] Don't do any early type 1 scanning. + This might help on some broken boards which + machine check when some devices' config space + is read. But various workarounds are disabled + and some IOMMU drivers will not work. pcmv= [HW,PCMCIA] BadgePAD 4 pd. [PARIDE] @@ -1363,6 +1365,14 @@ running once the system is up. reserve= [KNL,BUGS] Force the kernel to ignore some iomem area + reservetop= [IA-32] + Format: nn[KMG] + Reserves a hole at the top of the kernel virtual + address space. + + reset_devices [KNL] Force drivers to reset the underlying device + during initialization. + resume= [SWSUSP] Specify the partition device for software suspend diff --git a/Documentation/networking/bonding.txt b/Documentation/networking/bonding.txt index afac780445c..dc942eaf490 100644 --- a/Documentation/networking/bonding.txt +++ b/Documentation/networking/bonding.txt @@ -192,6 +192,17 @@ or, for backwards compatibility, the option value. E.g., arp_interval Specifies the ARP link monitoring frequency in milliseconds. + + The ARP monitor works by periodically checking the slave + devices to determine whether they have sent or received + traffic recently (the precise criteria depends upon the + bonding mode, and the state of the slave). Regular traffic is + generated via ARP probes issued for the addresses specified by + the arp_ip_target option. + + This behavior can be modified by the arp_validate option, + below. + If ARP monitoring is used in an etherchannel compatible mode (modes 0 and 2), the switch should be configured in a mode that evenly distributes packets across all links. If the @@ -213,6 +224,54 @@ arp_ip_target maximum number of targets that can be specified is 16. The default value is no IP addresses. +arp_validate + + Specifies whether or not ARP probes and replies should be + validated in the active-backup mode. This causes the ARP + monitor to examine the incoming ARP requests and replies, and + only consider a slave to be up if it is receiving the + appropriate ARP traffic. + + Possible values are: + + none or 0 + + No validation is performed. This is the default. + + active or 1 + + Validation is performed only for the active slave. + + backup or 2 + + Validation is performed only for backup slaves. + + all or 3 + + Validation is performed for all slaves. + + For the active slave, the validation checks ARP replies to + confirm that they were generated by an arp_ip_target. Since + backup slaves do not typically receive these replies, the + validation performed for backup slaves is on the ARP request + sent out via the active slave. It is possible that some + switch or network configurations may result in situations + wherein the backup slaves do not receive the ARP requests; in + such a situation, validation of backup slaves must be + disabled. + + This option is useful in network configurations in which + multiple bonding hosts are concurrently issuing ARPs to one or + more targets beyond a common switch. Should the link between + the switch and target fail (but not the switch itself), the + probe traffic generated by the multiple bonding instances will + fool the standard ARP monitor into considering the links as + still up. Use of the arp_validate option can resolve this, as + the ARP monitor will only consider ARP requests and replies + associated with its own instance of bonding. + + This option was added in bonding version 3.1.0. + downdelay Specifies the time, in milliseconds, to wait before disabling diff --git a/Documentation/networking/dccp.txt b/Documentation/networking/dccp.txt index c45daabd3bf..74563b38ffd 100644 --- a/Documentation/networking/dccp.txt +++ b/Documentation/networking/dccp.txt @@ -1,7 +1,6 @@ DCCP protocol ============ -Last updated: 10 November 2005 Contents ======== @@ -42,8 +41,11 @@ Socket options DCCP_SOCKOPT_PACKET_SIZE is used for CCID3 to set default packet size for calculations. -DCCP_SOCKOPT_SERVICE sets the service. This is compulsory as per the -specification. If you don't set it you will get EPROTO. +DCCP_SOCKOPT_SERVICE sets the service. The specification mandates use of +service codes (RFC 4340, sec. 8.1.2); if this socket option is not set, +the socket will fall back to 0 (which means that no meaningful service code +is present). Connecting sockets set at most one service option; for +listening sockets, multiple service codes can be specified. Notes ===== diff --git a/Documentation/nommu-mmap.txt b/Documentation/nommu-mmap.txt index b88ebe4d808..7714f57caad 100644 --- a/Documentation/nommu-mmap.txt +++ b/Documentation/nommu-mmap.txt @@ -116,6 +116,9 @@ FURTHER NOTES ON NO-MMU MMAP (*) A list of all the mappings on the system is visible through /proc/maps in no-MMU mode. + (*) A list of all the mappings in use by a process is visible through + /proc/<pid>/maps in no-MMU mode. + (*) Supplying MAP_FIXED or a requesting a particular mapping address will result in an error. @@ -125,6 +128,49 @@ FURTHER NOTES ON NO-MMU MMAP error will result if they don't. This is most likely to be encountered with character device files, pipes, fifos and sockets. + +========================== +INTERPROCESS SHARED MEMORY +========================== + +Both SYSV IPC SHM shared memory and POSIX shared memory is supported in NOMMU +mode. The former through the usual mechanism, the latter through files created +on ramfs or tmpfs mounts. + + +======= +FUTEXES +======= + +Futexes are supported in NOMMU mode if the arch supports them. An error will +be given if an address passed to the futex system call lies outside the +mappings made by a process or if the mapping in which the address lies does not +support futexes (such as an I/O chardev mapping). + + +============= +NO-MMU MREMAP +============= + +The mremap() function is partially supported. It may change the size of a +mapping, and may move it[*] if MREMAP_MAYMOVE is specified and if the new size +of the mapping exceeds the size of the slab object currently occupied by the +memory to which the mapping refers, or if a smaller slab object could be used. + +MREMAP_FIXED is not supported, though it is ignored if there's no change of +address and the object does not need to be moved. + +Shared mappings may not be moved. Shareable mappings may not be moved either, +even if they are not currently shared. + +The mremap() function must be given an exact match for base address and size of +a previously mapped object. It may not be used to create holes in existing +mappings, move parts of existing mappings or resize parts of mappings. It must +act on a complete mapping. + +[*] Not currently supported. + |