diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/feature-removal-schedule.txt | 22 | ||||
| -rw-r--r-- | Documentation/networking/bonding.txt | 110 | ||||
| -rw-r--r-- | Documentation/networking/dm9000.txt | 167 | ||||
| -rw-r--r-- | Documentation/networking/ip-sysctl.txt | 21 | ||||
| -rw-r--r-- | Documentation/networking/ixgb.txt | 419 | ||||
| -rw-r--r-- | Documentation/networking/mac80211_hwsim/README | 67 | ||||
| -rw-r--r-- | Documentation/networking/mac80211_hwsim/hostapd.conf | 11 | ||||
| -rw-r--r-- | Documentation/networking/mac80211_hwsim/wpa_supplicant.conf | 10 | ||||
| -rw-r--r-- | Documentation/networking/multiqueue.txt | 90 | ||||
| -rw-r--r-- | Documentation/networking/s2io.txt | 7 | ||||
| -rw-r--r-- | Documentation/powerpc/booting-without-of.txt | 78 | ||||
| -rw-r--r-- | Documentation/rfkill.txt | 547 |
12 files changed, 1262 insertions, 287 deletions
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 65a1482457a..86334b6f823 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -308,9 +308,31 @@ Who: Matthew Wilcox <willy@linux.intel.com> --------------------------- +What: SCTP_GET_PEER_ADDRS_NUM_OLD, SCTP_GET_PEER_ADDRS_OLD, + SCTP_GET_LOCAL_ADDRS_NUM_OLD, SCTP_GET_LOCAL_ADDRS_OLD +When: June 2009 +Why: A newer version of the options have been introduced in 2005 that + removes the limitions of the old API. The sctp library has been + converted to use these new options at the same time. Any user + space app that directly uses the old options should convert to using + the new options. +Who: Vlad Yasevich <vladislav.yasevich@hp.com> + +--------------------------- + What: CONFIG_THERMAL_HWMON When: January 2009 Why: This option was introduced just to allow older lm-sensors userspace to keep working over the upgrade to 2.6.26. At the scheduled time of removal fixed lm-sensors (2.x or 3.x) should be readily available. Who: Rene Herman <rene.herman@gmail.com> + +--------------------------- + +What: Code that is now under CONFIG_WIRELESS_EXT_SYSFS + (in net/core/net-sysfs.c) +When: After the only user (hal) has seen a release with the patches + for enough time, probably some time in 2010. +Why: Over 1K .text/.data size reduction, data is available in other + ways (ioctls) +Who: Johannes Berg <johannes@sipsolutions.net> diff --git a/Documentation/networking/bonding.txt b/Documentation/networking/bonding.txt index a0cda062bc3..7fa7fe71d7a 100644 --- a/Documentation/networking/bonding.txt +++ b/Documentation/networking/bonding.txt @@ -289,35 +289,73 @@ downdelay fail_over_mac Specifies whether active-backup mode should set all slaves to - the same MAC address (the traditional behavior), or, when - enabled, change the bond's MAC address when changing the - active interface (i.e., fail over the MAC address itself). - - Fail over MAC is useful for devices that cannot ever alter - their MAC address, or for devices that refuse incoming - broadcasts with their own source MAC (which interferes with - the ARP monitor). - - The down side of fail over MAC is that every device on the - network must be updated via gratuitous ARP, vs. just updating - a switch or set of switches (which often takes place for any - traffic, not just ARP traffic, if the switch snoops incoming - traffic to update its tables) for the traditional method. If - the gratuitous ARP is lost, communication may be disrupted. - - When fail over MAC is used in conjuction with the mii monitor, - devices which assert link up prior to being able to actually - transmit and receive are particularly susecptible to loss of - the gratuitous ARP, and an appropriate updelay setting may be - required. - - A value of 0 disables fail over MAC, and is the default. A - value of 1 enables fail over MAC. This option is enabled - automatically if the first slave added cannot change its MAC - address. This option may be modified via sysfs only when no - slaves are present in the bond. - - This option was added in bonding version 3.2.0. + the same MAC address at enslavement (the traditional + behavior), or, when enabled, perform special handling of the + bond's MAC address in accordance with the selected policy. + + Possible values are: + + none or 0 + + This setting disables fail_over_mac, and causes + bonding to set all slaves of an active-backup bond to + the same MAC address at enslavement time. This is the + default. + + active or 1 + + The "active" fail_over_mac policy indicates that the + MAC address of the bond should always be the MAC + address of the currently active slave. The MAC + address of the slaves is not changed; instead, the MAC + address of the bond changes during a failover. + + This policy is useful for devices that cannot ever + alter their MAC address, or for devices that refuse + incoming broadcasts with their own source MAC (which + interferes with the ARP monitor). + + The down side of this policy is that every device on + the network must be updated via gratuitous ARP, + vs. just updating a switch or set of switches (which + often takes place for any traffic, not just ARP + traffic, if the switch snoops incoming traffic to + update its tables) for the traditional method. If the + gratuitous ARP is lost, communication may be + disrupted. + + When this policy is used in conjuction with the mii + monitor, devices which assert link up prior to being + able to actually transmit and receive are particularly + susecptible to loss of the gratuitous ARP, and an + appropriate updelay setting may be required. + + follow or 2 + + The "follow" fail_over_mac policy causes the MAC + address of the bond to be selected normally (normally + the MAC address of the first slave added to the bond). + However, the second and subsequent slaves are not set + to this MAC address while they are in a backup role; a + slave is programmed with the bond's MAC address at + failover time (and the formerly active slave receives + the newly active slave's MAC address). + + This policy is useful for multiport devices that + either become confused or incur a performance penalty + when multiple ports are programmed with the same MAC + address. + + + The default policy is none, unless the first slave cannot + change its MAC address, in which case the active policy is + selected by default. + + This option may be modified via sysfs only when no slaves are + present in the bond. + + This option was added in bonding version 3.2.0. The "follow" + policy was added in bonding version 3.3.0. lacp_rate @@ -338,7 +376,8 @@ max_bonds Specifies the number of bonding devices to create for this instance of the bonding driver. E.g., if max_bonds is 3, and the bonding driver is not already loaded, then bond0, bond1 - and bond2 will be created. The default value is 1. + and bond2 will be created. The default value is 1. Specifying + a value of 0 will load bonding, but will not create any devices. miimon @@ -501,6 +540,17 @@ mode swapped with the new curr_active_slave that was chosen. +num_grat_arp + + Specifies the number of gratuitous ARPs to be issued after a + failover event. One gratuitous ARP is issued immediately after + the failover, subsequent ARPs are sent at a rate of one per link + monitor interval (arp_interval or miimon, whichever is active). + + The valid range is 0 - 255; the default value is 1. This option + affects only the active-backup mode. This option was added for + bonding version 3.3.0. + primary A string (eth0, eth2, etc) specifying which slave is the diff --git a/Documentation/networking/dm9000.txt b/Documentation/networking/dm9000.txt new file mode 100644 index 00000000000..65df3dea556 --- /dev/null +++ b/Documentation/networking/dm9000.txt @@ -0,0 +1,167 @@ +DM9000 Network driver +===================== + +Copyright 2008 Simtec Electronics, + Ben Dooks <ben@simtec.co.uk> <ben-linux@fluff.org> + + +Introduction +------------ + +This file describes how to use the DM9000 platform-device based network driver +that is contained in the files drivers/net/dm9000.c and drivers/net/dm9000.h. + +The driver supports three DM9000 variants, the DM9000E which is the first chip +supported as well as the newer DM9000A and DM9000B devices. It is currently +maintained and tested by Ben Dooks, who should be CC: to any patches for this +driver. + + +Defining the platform device +---------------------------- + +The minimum set of resources attached to the platform device are as follows: + + 1) The physical address of the address register + 2) The physical address of the data register + 3) The IRQ line the device's interrupt pin is connected to. + +These resources should be specified in that order, as the ordering of the +two address regions is important (the driver expects these to be address +and then data). + +An example from arch/arm/mach-s3c2410/mach-bast.c is: + +static struct resource bast_dm9k_resource[] = { + [0] = { + .start = S3C2410_CS5 + BAST_PA_DM9000, + .end = S3C2410_CS5 + BAST_PA_DM9000 + 3, + .flags = IORESOURCE_MEM, + }, + [1] = { + .start = S3C2410_CS5 + BAST_PA_DM9000 + 0x40, + .end = S3C2410_CS5 + BAST_PA_DM9000 + 0x40 + 0x3f, + .flags = IORESOURCE_MEM, + }, + [2] = { + .start = IRQ_DM9000, + .end = IRQ_DM9000, + .flags = IORESOURCE_IRQ | IORESOURCE_IRQ_HIGHLEVEL, + } +}; + +static struct platform_device bast_device_dm9k = { + .name = "dm9000", + .id = 0, + .num_resources = ARRAY_SIZE(bast_dm9k_resource), + .resource = bast_dm9k_resource, +}; + +Note the setting of the IRQ trigger flag in bast_dm9k_resource[2].flags, +as this will generate a warning if it is not present. The trigger from +the flags field will be passed to request_irq() when registering the IRQ +handler to ensure that the IRQ is setup correctly. + +This shows a typical platform device, without the optional configuration +platform data supplied. The next example uses the same resources, but adds +the optional platform data to pass extra configuration data: + +static struct dm9000_plat_data bast_dm9k_platdata = { + .flags = DM9000_PLATF_16BITONLY, +}; + +static struct platform_device bast_device_dm9k = { + .name = "dm9000", + .id = 0, + .num_resources = ARRAY_SIZE(bast_dm9k_resource), + .resource = bast_dm9k_resource, + .dev = { + .platform_data = &bast_dm9k_platdata, + } +}; + +The platform data is defined in include/linux/dm9000.h and described below. + + +Platform data +------------- + +Extra platform data for the DM9000 can describe the IO bus width to the +device, whether or not an external PHY is attached to the device and +the availability of an external configuration EEPROM. + +The flags for the platform data .flags field are as follows: + +DM9000_PLATF_8BITONLY + + The IO should be done with 8bit operations. + +DM9000_PLATF_16BITONLY + + The IO should be done with 16bit operations. + +DM9000_PLATF_32BITONLY + + The IO should be done with 32bit operations. + +DM9000_PLATF_EXT_PHY + + The chip is connected to an external PHY. + +DM9000_PLATF_NO_EEPROM + + This can be used to signify that the board does not have an + EEPROM, or that the EEPROM should be hidden from the user. + +DM9000_PLATF_SIMPLE_PHY + + Switch to using the simpler PHY polling method which does not + try and read the MII PHY state regularly. This is only available + when using the internal PHY. See the section on link state polling + for more information. + + The config symbol DM9000_FORCE_SIMPLE_PHY_POLL, Kconfig entry + "Force simple NSR based PHY polling" allows this flag to be + forced on at build time. + + +PHY Link state polling +---------------------- + +The driver keeps track of the link state and informs the network core +about link (carrier) availablilty. This is managed by several methods +depending on the version of the chip and on which PHY is being used. + +For the internal PHY, the original (and currently default) method is +to read the MII state, either when the status changes if we have the +necessary interrupt support in the chip or every two seconds via a +periodic timer. + +To reduce the overhead for the internal PHY, there is now the option +of using the DM9000_FORCE_SIMPLE_PHY_POLL config, or DM9000_PLATF_SIMPLE_PHY +platform data option to read the summary information without the +expensive MII accesses. This method is faster, but does not print +as much information. + +When using an external PHY, the driver currently has to poll the MII +link status as there is no method for getting an interrupt on link change. + + +DM9000A / DM9000B +----------------- + +These chips are functionally similar to the DM9000E and are supported easily +by the same driver. The features are: + + 1) Interrupt on internal PHY state change. This means that the periodic + polling of the PHY status may be disabled on these devices when using + the internal PHY. + + 2) TCP/UDP checksum offloading, which the driver does not currently support. + + +ethtool +------- + +The driver supports the ethtool interface for access to the driver +state information, the PHY state and the EEPROM. diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index 946b66e1b65..d84932650fd 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -551,8 +551,9 @@ icmp_echo_ignore_broadcasts - BOOLEAN icmp_ratelimit - INTEGER Limit the maximal rates for sending ICMP packets whose type matches icmp_ratemask (see below) to specific targets. - 0 to disable any limiting, otherwise the maximal rate in jiffies(1) - Default: 100 + 0 to disable any limiting, + otherwise the minimal space between responses in milliseconds. + Default: 1000 icmp_ratemask - INTEGER Mask made of ICMP types for which rates are being limited. @@ -1023,11 +1024,23 @@ max_addresses - INTEGER autoconfigured addresses. Default: 16 +disable_ipv6 - BOOLEAN + Disable IPv6 operation. + Default: FALSE (enable IPv6 operation) + +accept_dad - INTEGER + Whether to accept DAD (Duplicate Address Detection). + 0: Disable DAD + 1: Enable DAD (default) + 2: Enable DAD, and disable IPv6 operation if MAC-based duplicate + link-local address has been found. + icmp/*: ratelimit - INTEGER Limit the maximal rates for sending ICMPv6 packets. - 0 to disable any limiting, otherwise the maximal rate in jiffies(1) - Default: 100 + 0 to disable any limiting, + otherwise the minimal space between responses in milliseconds. + Default: 1000 IPv6 Update by: diff --git a/Documentation/networking/ixgb.txt b/Documentation/networking/ixgb.txt index 7c98277777e..a0d0ffb5e58 100644 --- a/Documentation/networking/ixgb.txt +++ b/Documentation/networking/ixgb.txt @@ -1,7 +1,7 @@ -Linux* Base Driver for the Intel(R) PRO/10GbE Family of Adapters -================================================================ +Linux Base Driver for 10 Gigabit Intel(R) Network Connection +============================================================= -November 17, 2004 +October 9, 2007 Contents @@ -9,94 +9,151 @@ Contents - In This Release - Identifying Your Adapter +- Building and Installation - Command Line Parameters - Improving Performance +- Additional Configurations +- Known Issues/Troubleshooting - Support + In This Release =============== -This file describes the Linux* Base Driver for the Intel(R) PRO/10GbE Family -of Adapters, version 1.0.x. +This file describes the ixgb Linux Base Driver for the 10 Gigabit Intel(R) +Network Connection. This driver includes support for Itanium(R)2-based +systems. + +For questions related to hardware requirements, refer to the documentation +supplied with your 10 Gigabit adapter. All hardware requirements listed apply +to use with Linux. + +The following features are available in this kernel: + - Native VLANs + - Channel Bonding (teaming) + - SNMP + +Channel Bonding documentation can be found in the Linux kernel source: +/Documentation/networking/bonding.txt + +The driver information previously displayed in the /proc filesystem is not +supported in this release. Alternatively, you can use ethtool (version 1.6 +or later), lspci, and ifconfig to obtain the same information. + +Instructions on updating ethtool can be found in the section "Additional +Configurations" later in this document. -For questions related to hardware requirements, refer to the documentation -supplied with your Intel PRO/10GbE adapter. All hardware requirements listed -apply to use with Linux. Identifying Your Adapter ======================== -To verify your Intel adapter is supported, find the board ID number on the -adapter. Look for a label that has a barcode and a number in the format -A12345-001. +The following Intel network adapters are compatible with the drivers in this +release: + +Controller Adapter Name Physical Layer +---------- ------------ -------------- +82597EX Intel(R) PRO/10GbE LR/SR/CX4 10G Base-LR (1310 nm optical fiber) + Server Adapters 10G Base-SR (850 nm optical fiber) + 10G Base-CX4(twin-axial copper cabling) + +For more information on how to identify your adapter, go to the Adapter & +Driver ID Guide at: + + http://support.intel.com/support/network/sb/CS-012904.htm + + +Building and Installation +========================= + +select m for "Intel(R) PRO/10GbE support" located at: + Location: + -> Device Drivers + -> Network device support (NETDEVICES [=y]) + -> Ethernet (10000 Mbit) (NETDEV_10000 [=y]) +1. make modules && make modules_install + +2. Load the module: + + modprobe ixgb <parameter>=<value> + + The insmod command can be used if the full + path to the driver module is specified. For example: + + insmod /lib/modules/<KERNEL VERSION>/kernel/drivers/net/ixgb/ixgb.ko + + With 2.6 based kernels also make sure that older ixgb drivers are + removed from the kernel, before loading the new module: -Use the above information and the Adapter & Driver ID Guide at: + rmmod ixgb; modprobe ixgb - http://support.intel.com/support/network/adapter/pro100/21397.htm +3. Assign an IP address to the interface by entering the following, where + x is the interface number: -For the latest Intel network drivers for Linux, go to: + ifconfig ethx <IP_address> + +4. Verify that the interface works. Enter the following, where <IP_address> + is the IP address for another machine on the same subnet as the interface + that is being tested: + + ping <IP_address> - http://downloadfinder.intel.com/scripts-df/support_intel.asp Command Line Parameters ======================= -If the driver is built as a module, the following optional parameters are -used by entering them on the command line with the modprobe or insmod command -using this syntax: +If the driver is built as a module, the following optional parameters are +used by entering them on the command line with the modprobe command using +this syntax: modprobe ixgb [<option>=<VAL1>,<VAL2>,...] - insmod ixgb [<option>=<VAL1>,<VAL2>,...] +For example, with two 10GbE PCI adapters, entering: -For example, with two PRO/10GbE PCI adapters, entering: + modprobe ixgb TxDescriptors=80,128 - insmod ixgb TxDescriptors=80,128 - -loads the ixgb driver with 80 TX resources for the first adapter and 128 TX +loads the ixgb driver with 80 TX resources for the first adapter and 128 TX resources for the second adapter. The default value for each parameter is generally the recommended setting, -unless otherwise noted. Also, if the driver is statically built into the -kernel, the driver is loaded with the default values for all the parameters. -Ethtool can be used to change some of the parameters at runtime. +unless otherwise noted. FlowControl Valid Range: 0-3 (0=none, 1=Rx only, 2=Tx only, 3=Rx&Tx) Default: Read from the EEPROM - If EEPROM is not detected, default is 3 - This parameter controls the automatic generation(Tx) and response(Rx) to - Ethernet PAUSE frames. + If EEPROM is not detected, default is 1 + This parameter controls the automatic generation(Tx) and response(Rx) to + Ethernet PAUSE frames. There are hardware bugs associated with enabling + Tx flow control so beware. RxDescriptors Valid Range: 64-512 Default Value: 512 - This value is the number of receive descriptors allocated by the driver. - Increasing this value allows the driver to buffer more incoming packets. - Each descriptor is 16 bytes. A receive buffer is also allocated for - each descriptor and can be either 2048, 4056, 8192, or 16384 bytes, - depending on the MTU setting. When the MTU size is 1500 or less, the + This value is the number of receive descriptors allocated by the driver. + Increasing this value allows the driver to buffer more incoming packets. + Each descriptor is 16 bytes. A receive buffer is also allocated for + each descriptor and can be either 2048, 4056, 8192, or 16384 bytes, + depending on the MTU setting. When the MTU size is 1500 or less, the receive buffer size is 2048 bytes. When the MTU is greater than 1500 the - receive buffer size will be either 4056, 8192, or 16384 bytes. The + receive buffer size will be either 4056, 8192, or 16384 bytes. The maximum MTU size is 16114. RxIntDelay Valid Range: 0-65535 (0=off) -Default Value: 6 - This value delays the generation of receive interrupts in units of - 0.8192 microseconds. Receive interrupt reduction can improve CPU - efficiency if properly tuned for specific network traffic. Increasing - this value adds extra latency to frame reception and can end up - decreasing the throughput of TCP traffic. If the system is reporting - dropped receives, this value may be set too high, causing the driver to +Default Value: 72 + This value delays the generation of receive interrupts in units of + 0.8192 microseconds. Receive interrupt reduction can improve CPU + efficiency if properly tuned for specific network traffic. Increasing + this value adds extra latency to frame reception and can end up + decreasing the throughput of TCP traffic. If the system is reporting + dropped receives, this value may be set too high, causing the driver to run out of available receive descriptors. TxDescriptors Valid Range: 64-4096 Default Value: 256 This value is the number of transmit descriptors allocated by the driver. - Increasing this value allows the driver to queue more transmits. Each + Increasing this value allows the driver to queue more transmits. Each descriptor is 16 bytes. XsumRX @@ -105,51 +162,49 @@ Default Value: 1 A value of '1' indicates that the driver should enable IP checksum offload for received packets (both UDP and TCP) to the adapter hardware. -XsumTX -Valid Range: 0-1 -Default Value: 1 - A value of '1' indicates that the driver should enable IP checksum - offload for transmitted packets (both UDP and TCP) to the adapter - hardware. Improving Performance ===================== -With the Intel PRO/10 GbE adapter, the default Linux configuration will very -likely limit the total available throughput artificially. There is a set of -things that when applied together increase the ability of Linux to transmit -and receive data. The following enhancements were originally acquired from -settings published at http://www.spec.org/web99 for various submitted results -using Linux. +With the 10 Gigabit server adapters, the default Linux configuration will +very likely limit the total available throughput artificially. There is a set +of configuration changes that, when applied together, will increase the ability +of Linux to transmit and receive data. The following enhancements were +originally acquired from settings published at http://www.spec.org/web99/ for +various submitted results using Linux. -NOTE: These changes are only suggestions, and serve as a starting point for -tuning your network performance. +NOTE: These changes are only suggestions, and serve as a starting point for + tuning your network performance. The changes are made in three major ways, listed in order of greatest effect: -- Use ifconfig to modify the mtu (maximum transmission unit) and the txqueuelen +- Use ifconfig to modify the mtu (maximum transmission unit) and the txqueuelen parameter. - Use sysctl to modify /proc parameters (essentially kernel tuning) -- Use setpci to modify the MMRBC field in PCI-X configuration space to increase +- Use setpci to modify the MMRBC field in PCI-X configuration space to increase transmit burst lengths on the bus. -NOTE: setpci modifies the adapter's configuration registers to allow it to read -up to 4k bytes at a time (for transmits). However, for some systems the -behavior after modifying this register may be undefined (possibly errors of some -kind). A power-cycle, hard reset or explicitly setting the e6 register back to -22 (setpci -d 8086:1048 e6.b=22) may be required to get back to a stable -configuration. +NOTE: setpci modifies the adapter's configuration registers to allow it to read +up to 4k bytes at a time (for transmits). However, for some systems the +behavior after modifying this register may be undefined (possibly errors of +some kind). A power-cycle, hard reset or explicitly setting the e6 register +back to 22 (setpci -d 8086:1a48 e6.b=22) may be required to get back to a +stable configuration. - COPY these lines and paste them into ixgb_perf.sh: #!/bin/bash -echo "configuring network performance , edit this file to change the interface" +echo "configuring network performance , edit this file to change the interface +or device ID of 10GbE card" # set mmrbc to 4k reads, modify only Intel 10GbE device IDs -setpci -d 8086:1048 e6.b=2e -# set the MTU (max transmission unit) - it requires your switch and clients to change too! +# replace 1a48 with appropriate 10GbE device's ID installed on the system, +# if needed. +setpci -d 8086:1a48 e6.b=2e +# set the MTU (max transmission unit) - it requires your switch and clients +# to change as well. # set the txqueuelen # your ixgb adapter should be loaded as eth1 for this to work, change if needed ifconfig eth1 mtu 9000 txqueuelen 1000 up -# call the sysctl utility to modify /proc/sys entries -sysctl -p ./sysctl_ixgb.conf +# call the sysctl utility to modify /proc/sys entries +sysctl -p ./sysctl_ixgb.conf - END ixgb_perf.sh - COPY these lines and paste them into sysctl_ixgb.conf: @@ -159,54 +214,220 @@ sysctl -p ./sysctl_ixgb.conf # several network benchmark tests, your mileage may vary ### IPV4 specific settings -net.ipv4.tcp_timestamps = 0 # turns TCP timestamp support off, default 1, reduces CPU use -net.ipv4.tcp_sack = 0 # turn SACK support off, default on -# on systems with a VERY fast bus -> memory interface this is the big gainer -net.ipv4.tcp_rmem = 10000000 10000000 10000000 # sets min/default/max TCP read buffer, default 4096 87380 174760 -net.ipv4.tcp_wmem = 10000000 10000000 10000000 # sets min/pressure/max TCP write buffer, default 4096 16384 131072 -net.ipv4.tcp_mem = 10000000 10000000 10000000 # sets min/pressure/max TCP buffer space, default 31744 32256 32768 +# turn TCP timestamp support off, default 1, reduces CPU use +net.ipv4.tcp_timestamps = 0 +# turn SACK support off, default on +# on systems with a VERY fast bus -> memory interface this is the big gainer +net.ipv4.tcp_sack = 0 +# set min/default/max TCP read buffer, default 4096 87380 174760 +net.ipv4.tcp_rmem = 10000000 10000000 10000000 +# set min/pressure/max TCP write buffer, default 4096 16384 131072 +net.ipv4.tcp_wmem = 10000000 10000000 10000000 +# set min/pressure/max TCP buffer space, default 31744 32256 32768 +net.ipv4.tcp_mem = 10000000 10000000 10000000 ### CORE settings (mostly for socket and UDP effect) -net.core.rmem_max = 524287 # maximum receive socket buffer size, default 131071 -net.core.wmem_max = 524287 # maximum send socket buffer size, default 131071 -net.core.rmem_default = 524287 # default receive socket buffer size, default 65535 -net.core.wmem_default = 524287 # default send socket buffer size, default 65535 -net.core.optmem_max = 524287 # maximum amount of option memory buffers, default 10240 -net.core.netdev_max_backlog = 300000 # number of unprocessed input packets before kernel starts dropping them, default 300 +# set maximum receive socket buffer size, default 131071 +net.core.rmem_max = 524287 +# set maximum send socket buffer size, default 131071 +net.core.wmem_max = 524287 +# set default receive socket buffer size, default 65535 +net.core.rmem_default = 524287 +# set default send socket buffer size, default 65535 +net.core.wmem_default = 524287 +# set maximum amount of option memory buffers, default 10240 +net.core.optmem_max = 524287 +# set number of unprocessed input packets before kernel starts dropping them; default 300 +net.core.netdev_max_backlog = 300000 - END sysctl_ixgb.conf -Edit the ixgb_perf.sh script if necessary to change eth1 to whatever interface -your ixgb driver is using. +Edit the ixgb_perf.sh script if necessary to change eth1 to whatever interface +your ixgb driver is using and/or replace '1a48' with appropriate 10GbE device's +ID installed on the system. -NOTE: Unless these scripts are added to the boot process, these changes will -only last only until the next system reboot. +NOTE: Unless these scripts are added to the boot process, these changes will + only last only until the next system reboot. Resolving Slow UDP Traffic -------------------------- +If your server does not seem to be able to receive UDP traffic as fast as it +can receive TCP traffic, it could be because Linux, by default, does not set +the network stack buffers as large as they need to be to support high UDP +transfer rates. One way to alleviate this problem is to allow more memory to +be used by the IP stack to store incoming data. -If your server does not seem to be able to receive UDP traffic as fast as it -can receive TCP traffic, it could be because Linux, by default, does not set -the network stack buffers as large as they need to be to support high UDP -transfer rates. One way to alleviate this problem is to allow more memory to -be used by the IP stack to store incoming data. - -For instance, use the commands: +For instance, use the commands: sysctl -w net.core.rmem_max=262143 and sysctl -w net.core.rmem_default=262143 -to increase the read buffer memory max and default to 262143 (256k - 1) from -defaults of max=131071 (128k - 1) and default=65535 (64k - 1). These variables -will increase the amount of memory used by the network stack for receives, and +to increase the read buffer memory max and default to 262143 (256k - 1) from +defaults of max=131071 (128k - 1) and default=65535 (64k - 1). These variables +will increase the amount of memory used by the network stack for receives, and can be increased significantly more if necessary for your application. + +Additional Configurations +========================= + + Configuring the Driver on Different Distributions + ------------------------------------------------- + Configuring a network driver to load properly when the system is started is + distribution dependent. Typically, the configuration process involves adding + an alias line to /etc/modprobe.conf as well as editing other system startup + scripts and/or configuration files. Many popular Linux distributions ship + with tools to make these changes for you. To learn the proper way to + configure a network device for your system, refer to your distribution + documentation. If during this process you are asked for the driver or module + name, the name for the Linux Base Driver for the Intel 10GbE Family of + Adapters is ixgb. + + Viewing Link Messages + --------------------- + Link messages will not be displayed to the console if the distribution is + restricting system messages. In order to see network driver link messages on + your console, set dmesg to eight by entering the following: + + dmesg -n 8 + + NOTE: This setting is not saved across reboots. + + + Jumbo Frames + ------------ + The driver supports Jumbo Frames for all adapters. Jumbo Frames support is + enabled by changing the MTU to a value larger than the default of 1500. + The maximum value for the MTU is 16114. Use the ifconfig command to + increase the MTU size. For example: + + ifconfig ethx mtu 9000 up + + The maximum MTU setting for Jumbo Frames is 16114. This value coincides + with the maximum Jumbo Frames size of 16128. + + + Ethtool + ------- + The driver utilizes the ethtool interface for driver configuration and + diagnostics, as well as displaying statistical information. Ethtool + version 1.6 or later is required for this functionality. + + The latest release of ethtool can be found from + http://sourceforge.net/projects/gkernel + + NOTE: Ethtool 1.6 only supports a limited set of ethtool options. Support + for a more complete ethtool feature set can be enabled by upgrading + to the latest version. + + + NAPI + ---- + + NAPI (Rx polling mode) is supported in the ixgb driver. NAPI is enabled + or disabled based on the configuration of the kernel. see CONFIG_IXGB_NAPI + + See www.cyberus.ca/~hadi/usenix-paper.tgz for more information on NAPI. + + +Known Issues/Troubleshooting +============================ + + NOTE: After installing the driver, if your Intel Network Connection is not + working, verify in the "In This Release" section of the readme that you have + installed the correct driver. + + Intel(R) PRO/10GbE CX4 Server Adapter Cable Interoperability Issue with + Fujitsu XENPAK Module in SmartBits Chassis + --------------------------------------------------------------------- + Excessive CRC errors may be observed if the Intel(R) PRO/10GbE CX4 + Server adapter is connected to a Fujitsu XENPAK CX4 module in a SmartBits + chassis using 15 m/24AWG cable assemblies manufactured by Fujitsu or Leoni. + The CRC errors may be received either by the Intel(R) PRO/10GbE CX4 + Server adapter or the SmartBits. If this situation occurs using a different + cable assembly may resolve the issue. + + CX4 Server Adapter Cable Interoperability Issues with HP Procurve 3400cl + Switch Port + ------------------------------------------------------------------------ + Excessive CRC errors may be observed if the Intel(R) PRO/10GbE CX4 Server + adapter is connected to an HP Procurve 3400cl switch port using short cables + (1 m or shorter). If this situation occurs, using a longer cable may resolve + the issue. + + Excessive CRC errors may be observed using Fujitsu 24AWG cable assemblies that + Are 10 m or longer or where using a Leoni 15 m/24AWG cable assembly. The CRC + errors may be received either by the CX4 Server adapter or at the switch. If + this situation occurs, using a different cable assembly may resolve the issue. + + + Jumbo Frames System Requirement + ------------------------------- + Memory allocation failures have been observed on Linux systems with 64 MB + of RAM or less that are running Jumbo Frames. If you are using Jumbo + Frames, your system may require more than the advertised minimum + requirement of 64 MB of system memory. + + + Performance Degradation with Jumbo Frames + ----------------------------------------- + Degradation in throughput performance may be observed in some Jumbo frames + environments. If this is observed, increasing the application's socket buffer + size and/or increasing the /proc/sys/net/ipv4/tcp_*mem entry values may help. + See the specific application manual and /usr/src/linux*/Documentation/ + networking/ip-sysctl.txt for more details. + + + Allocating Rx Buffers when Using Jumbo Frames + --------------------------------------------- + Allocating Rx buffers when using Jumbo Frames on 2.6.x kernels may fail if + the available memory is heavily fragmented. This issue may be seen with PCI-X + adapters or with packet split disabled. This can be reduced or eliminated + by changing the amount of available memory for receive buffer allocation, by + increasing /proc/sys/vm/min_free_kbytes. + + + Multiple Interfaces on Same Ethernet Broadcast Network + ------------------------------------------------------ + Due to the default ARP behavior on Linux, it is not possible to have + one system on two IP networks in the same Ethernet broadcast domain + (non-partitioned switch) behave as expected. All Ethernet interfaces + will respond to IP traffic for any IP address assigned to the system. + This results in unbalanced receive traffic. + + If you have multiple interfaces in a server, do either of the following: + + - Turn on ARP filtering by entering: + echo 1 > /proc/sys/net/ipv4/conf/all/arp_filter + + - Install the interfaces in separate broadcast domains - either in + different switches or in a switch partitioned to VLANs. + + + UDP Stress Test Dropped Packet Issue + -------------------------------------- + Under small packets UDP stress test with 10GbE driver, the Linux system + may drop UDP packets due to the fullness of socket buffers. You may want + to change the driver's Flow Control variables to the minimum value for + controlling packet reception. + + + Tx Hangs Possible Under Stress + ------------------------------ + Under stress conditions, if TX hangs occur, turning off TSO + "ethtool -K eth0 tso off" may resolve the problem. + + Support ======= -For general information and support, go to the Intel support website at: +For general information, go to the Intel support website at: http://support.intel.com +or the Intel Wired Networking project hosted by Sourceforge at: + + http://sourceforge.net/projects/e1000 + If an issue is identified with the released source code on the supported -kernel with a supported adapter, email the specific information related to -the issue to linux.nics@intel.com. +kernel with a supported adapter, email the specific information related +to the issue to e1000-devel@lists.sf.net diff --git a/Documentation/networking/mac80211_hwsim/README b/Documentation/networking/mac80211_hwsim/README new file mode 100644 index 00000000000..2ff8ccb8dc3 --- /dev/null +++ b/Documentation/networking/mac80211_hwsim/README @@ -0,0 +1,67 @@ +mac80211_hwsim - software simulator of 802.11 radio(s) for mac80211 +Copyright (c) 2008, Jouni Malinen <j@w1.fi> + +This program is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License version 2 as +published by the Free Software Foundation. + + +Introduction + +mac80211_hwsim is a Linux kernel module that can be used to simulate +arbitrary number of IEEE 802.11 radios for mac80211. It can be used to +test most of the mac80211 functionality and user space tools (e.g., +hostapd and wpa_supplicant) in a way that matches very closely with +the normal case of using real WLAN hardware. From the mac80211 view +point, mac80211_hwsim is yet another hardware driver, i.e., no changes +to mac80211 are needed to use this testing tool. + +The main goal for mac80211_hwsim is to make it easier for developers +to test their code and work with new features to mac80211, hostapd, +and wpa_supplicant. The simulated radios do not have the limitations +of real hardware, so it is easy to generate an arbitrary test setup +and always reproduce the same setup for future tests. In addition, +since all radio operation is simulated, any channel can be used in +tests regardless of regulatory rules. + +mac80211_hwsim kernel module has a parameter 'radios' that can be used +to select how many radios are simulated (default 2). This allows +configuration of both very simply setups (e.g., just a single access +point and a station) or large scale tests (multiple access points with +hundreds of stations). + +mac80211_hwsim works by tracking the current channel of each virtual +radio and copying all transmitted frames to all other radios that are +currently enabled and on the same channel as the transmitting +radio. Software encryption in mac80211 is used so that the frames are +actually encrypted over the virtual air interface to allow more +complete testing of encryption. + +A global monitoring netdev, hwsim#, is created independent of +mac80211. This interface can be used to monitor all transmitted frames +regardless of channel. + + +Simple example + +This example shows how to use mac80211_hwsim to simulate two radios: +one to act as an access point and the other as a station that +associates with the AP. hostapd and wpa_supplicant are used to take +care of WPA2-PSK authentication. In addition, hostapd is also +processing access point side of association. + +Please note that the current Linux kernel does not enable AP mode, so a +simple patch is needed to enable AP mode selection: +http://johannes.sipsolutions.net/patches/kernel/all/LATEST/006-allow-ap-vlan-modes.patch + + +# Build mac80211_hwsim as part of kernel configuration + +# Load the module +modprobe mac80211_hwsim + +# Run hostapd (AP) for wlan0 +hostapd hostapd.conf + +# Run wpa_supplicant (station) for wlan1 +wpa_supplicant -Dwext -iwlan1 -c wpa_supplicant.conf diff --git a/Documentation/networking/mac80211_hwsim/hostapd.conf b/Documentation/networking/mac80211_hwsim/hostapd.conf new file mode 100644 index 00000000000..08cde7e35f2 --- /dev/null +++ b/Documentation/networking/mac80211_hwsim/hostapd.conf @@ -0,0 +1,11 @@ +interface=wlan0 +driver=nl80211 + +hw_mode=g +channel=1 +ssid=mac80211 test + +wpa=2 +wpa_key_mgmt=WPA-PSK +wpa_pairwise=CCMP +wpa_passphrase=12345678 diff --git a/Documentation/networking/mac80211_hwsim/wpa_supplicant.conf b/Documentation/networking/mac80211_hwsim/wpa_supplicant.conf new file mode 100644 index 00000000000..299128cff03 --- /dev/null +++ b/Documentation/networking/mac80211_hwsim/wpa_supplicant.conf @@ -0,0 +1,10 @@ +ctrl_interface=/var/run/wpa_supplicant + +network={ + ssid="mac80211 test" + psk="12345678" + key_mgmt=WPA-PSK + proto=WPA2 + pairwise=CCMP + group=CCMP +} diff --git a/Documentation/networking/multiqueue.txt b/Documentation/networking/multiqueue.txt index ea5a42e8f79..d391ea63114 100644 --- a/Documentation/networking/multiqueue.txt +++ b/Documentation/networking/multiqueue.txt @@ -3,19 +3,11 @@ =========================================== Section 1: Base driver requirements for implementing multiqueue support -Section 2: Qdisc support for multiqueue devices -Section 3: Brief howto using PRIO or RR for multiqueue devices - Intro: Kernel support for multiqueue devices --------------------------------------------------------- -Kernel support for multiqueue devices is only an API that is presented to the -netdevice layer for base drivers to implement. This feature is part of the -core networking stack, and all network devices will be running on the -multiqueue-aware stack. If a base driver only has one queue, then these -changes are transparent to that driver. - +Kernel support for multiqueue devices is always present. Section 1: Base driver requirements for implementing multiqueue support ----------------------------------------------------------------------- @@ -32,84 +24,4 @@ netif_{start|stop|wake}_subqueue() functions to manage each queue while the device is still operational. netdev->queue_lock is still used when the device comes online or when it's completely shut down (unregister_netdev(), etc.). -Finally, the base driver should indicate that it is a multiqueue device. The -feature flag NETIF_F_MULTI_QUEUE should be added to the netdev->features -bitmap on device initialization. Below is an example from e1000: - -#ifdef CONFIG_E1000_MQ - if ( (adapter->hw.mac.type == e1000_82571) || - (adapter->hw.mac.type == e1000_82572) || - (adapter->hw.mac.type == e1000_80003es2lan)) - netdev->features |= NETIF_F_MULTI_QUEUE; -#endif - - -Section 2: Qdisc support for multiqueue devices ------------------------------------------------ - -Currently two qdiscs support multiqueue devices. A new round-robin qdisc, -sch_rr, and sch_prio. The qdisc is responsible for classifying the skb's to -bands and queues, and will store the queue mapping into skb->queue_mapping. -Use this field in the base driver to determine which queue to send the skb -to. - -sch_rr has been added for hardware that doesn't want scheduling policies from -software, so it's a straight round-robin qdisc. It uses the same syntax and -classification priomap that sch_prio uses, so it should be intuitive to -configure for people who've used sch_prio. - -In order to utilitize the multiqueue features of the qdiscs, the network -device layer needs to enable multiple queue support. This can be done by -selecting NETDEVICES_MULTIQUEUE under Drivers. - -The PRIO qdisc naturally plugs into a multiqueue device. If -NETDEVICES_MULTIQUEUE is selected, then on qdisc load, the number of -bands requested is compared to the number of queues on the hardware. If they -are equal, it sets a one-to-one mapping up between the queues and bands. If -they're not equal, it will not load the qdisc. This is the same behavior -for RR. Once the association is made, any skb that is classified will have -skb->queue_mapping set, which will allow the driver to properly queue skb's -to multiple queues. - - -Section 3: Brief howto using PRIO and RR for multiqueue devices ---------------------------------------------------------------- - -The userspace command 'tc,' part of the iproute2 package, is used to configure -qdiscs. To add the PRIO qdisc to your network device, assuming the device is -called eth0, run the following command: - -# tc qdisc add dev eth0 root handle 1: prio bands 4 multiqueue - -This will create 4 bands, 0 being highest priority, and associate those bands -to the queues on your NIC. Assuming eth0 has 4 Tx queues, the band mapping -would look like: - -band 0 => queue 0 -band 1 => queue 1 -band 2 => queue 2 -band 3 => queue 3 - -Traffic will begin flowing through each queue if your TOS values are assigning -traffic across the various bands. For example, ssh traffic will always try to -go out band 0 based on TOS -> Linux priority conversion (realtime traffic), -so it will be sent out queue 0. ICMP traffic (pings) fall into the "normal" -traffic classification, which is band 1. Therefore pings will be send out -queue 1 on the NIC. - -Note the use of the multiqueue keyword. This is only in versions of iproute2 -that support multiqueue networking devices; if this is omitted when loading -a qdisc onto a multiqueue device, the qdisc will load and operate the same -if it were loaded onto a single-queue device (i.e. - sends all traffic to -queue 0). - -Another alternative to multiqueue band allocation can be done by using the -multiqueue option and specify 0 bands. If this is the case, the qdisc will -allocate the number of bands to equal the number of queues that the device -reports, and bring the qdisc online. - -The behavior of tc filters remains the same, where it will override TOS priority -classification. - - Author: Peter P. Waskiewicz Jr. <peter.p.waskiewicz.jr@intel.com> diff --git a/Documentation/networking/s2io.txt b/Documentation/networking/s2io.txt index 1e28e2ddb90..c3d6b4d5d01 100644 --- a/Documentation/networking/s2io.txt +++ b/Documentation/networking/s2io.txt @@ -52,13 +52,10 @@ d. MSI/MSI-X. Can be enabled on platforms which support this feature (IA64, Xeon) resulting in noticeable performance improvement(upto 7% on certain platforms). -e. NAPI. Compile-time option(CONFIG_S2IO_NAPI) for better Rx interrupt -moderation. - -f. Statistics. Comprehensive MAC-level and software statistics displayed +e. Statistics. Comprehensive MAC-level and software statistics displayed using "ethtool -S" option. -g. Multi-FIFO/Ring. Supports up to 8 transmit queues and receive rings, +f. Multi-FIFO/Ring. Supports up to 8 transmit queues and receive rings, with multiple steering options. 4. Command line parameters diff --git a/Documentation/powerpc/booting-without-of.txt b/Documentation/powerpc/booting-without-of.txt index de2e5c05d6e..aee243a846a 100644 --- a/Documentation/powerpc/booting-without-of.txt +++ b/Documentation/powerpc/booting-without-of.txt @@ -41,12 +41,24 @@ Table of Contents VI - System-on-a-chip devices and nodes 1) Defining child nodes of an SOC 2) Representing devices without a current OF specification - a) PHY nodes - b) Interrupt controllers - c) CFI or JEDEC memory-mapped NOR flash - d) 4xx/Axon EMAC ethernet nodes - e) Xilinx IP cores - f) USB EHCI controllers + a) MDIO IO device + b) Gianfar-compatible ethernet nodes + c) PHY nodes + d) Interrupt controllers + e) I2C + f) Freescale SOC USB controllers + g) Freescale SOC SEC Security Engines + h) Board Control and Status (BCSR) + i) Freescale QUICC Engine module (QE) + j) CFI or JEDEC memory-mapped NOR flash + k) Global Utilities Block + l) Freescale Communications Processor Module + m) Chipselect/Local Bus + n) 4xx/Axon EMAC ethernet nodes + o) Xilinx IP cores + p) Freescale Synchronous Serial Interface + q) USB EHCI controllers + r) MDIO on GPIOs VII - Marvell Discovery mv64[345]6x System Controller chips 1) The /system-controller node @@ -1815,6 +1827,60 @@ platforms are moved over to use the flattened-device-tree model. big-endian; }; + r) Freescale Display Interface Unit + + The Freescale DIU is a LCD controller, with proper hardware, it can also + drive DVI monitors. + + Required properties: + - compatible : should be "fsl-diu". + - reg : should contain at least address and length of the DIU register + set. + - Interrupts : one DIU interrupt should be describe here. + + Example (MPC8610HPCD) + display@2c000 { + compatible = "fsl,diu"; + reg = <0x2c000 100>; + interrupts = <72 2>; + interrupt-parent = <&mpic>; + }; + + s) Freescale on board FPGA + + This is the memory-mapped registers for on board FPGA. + + Required properities: + - compatible : should be "fsl,fpga-pixis". + - reg : should contain the address and the lenght of the FPPGA register + set. + + Example (MPC8610HPCD) + board-control@e8000000 { + compatible = "fsl,fpga-pixis"; + reg = <0xe8000000 32>; + }; + + r) MDIO on GPIOs + + Currently defined compatibles: + - virtual,gpio-mdio + + MDC and MDIO lines connected to GPIO controllers are listed in the + gpios property as described in section VIII.1 in the following order: + + MDC, MDIO. + + Example: + + mdio { + compatible = "virtual,mdio-gpio"; + #address-cells = <1>; + #size-cells = <0>; + gpios = <&qe_pio_a 11 + &qe_pio_c 6>; + }; + VII - Marvell Discovery mv64[345]6x System Controller chips =========================================================== diff --git a/Documentation/rfkill.txt b/Documentation/rfkill.txt index a83ff23cd68..0843ed0163a 100644 --- a/Documentation/rfkill.txt +++ b/Documentation/rfkill.txt @@ -1,89 +1,528 @@ rfkill - RF switch subsystem support ==================================== -1 Implementation details -2 Driver support -3 Userspace support +1 Introduction +2 Implementation details +3 Kernel driver guidelines +3.1 wireless device drivers +3.2 platform/switch drivers +3.3 input device drivers +4 Kernel API +5 Userspace support -=============================================================================== -1: Implementation details -The rfkill switch subsystem offers support for keys often found on laptops -to enable wireless devices like WiFi and Bluetooth. +1. Introduction: + +The rfkill switch subsystem exists to add a generic interface to circuitry that +can enable or disable the signal output of a wireless *transmitter* of any +type. By far, the most common use is to disable radio-frequency transmitters. -This is done by providing the user 3 possibilities: - 1 - The rfkill system handles all events; userspace is not aware of events. - 2 - The rfkill system handles all events; userspace is informed about the events. - 3 - The rfkill system does not handle events; userspace handles all events. +Note that disabling the signal output means that the the transmitter is to be +made to not emit any energy when "blocked". rfkill is not about blocking data +transmissions, it is about blocking energy emission. -The buttons to enable and disable the wireless radios are important in +The rfkill subsystem offers support for keys and switches often found on +laptops to enable wireless devices like WiFi and Bluetooth, so that these keys +and switches actually perform an action in all wireless devices of a given type +attached to the system. + +The buttons to enable and disable the wireless transmitters are important in situations where the user is for example using his laptop on a location where -wireless radios _must_ be disabled (e.g. airplanes). -Because of this requirement, userspace support for the keys should not be -made mandatory. Because userspace might want to perform some additional smarter -tasks when the key is pressed, rfkill still provides userspace the possibility -to take over the task to handle the key events. +radio-frequency transmitters _must_ be disabled (e.g. airplanes). + +Because of this requirement, userspace support for the keys should not be made +mandatory. Because userspace might want to perform some additional smarter +tasks when the key is pressed, rfkill provides userspace the possibility to +take over the task to handle the key events. + +=============================================================================== +2: Implementation details + +The rfkill subsystem is composed of various components: the rfkill class, the +rfkill-input module (an input layer handler), and some specific input layer +events. + +The rfkill class provides kernel drivers with an interface that allows them to +know when they should enable or disable a wireless network device transmitter. +This is enabled by the CONFIG_RFKILL Kconfig option. + +The rfkill class support makes sure userspace will be notified of all state +changes on rfkill devices through uevents. It provides a notification chain +for interested parties in the kernel to also get notified of rfkill state +changes in other drivers. It creates several sysfs entries which can be used +by userspace. See section "Userspace support". + +The rfkill-input module provides the kernel with the ability to implement a +basic response when the user presses a key or button (or toggles a switch) +related to rfkill functionality. It is an in-kernel implementation of default +policy of reacting to rfkill-related input events and neither mandatory nor +required for wireless drivers to operate. It is enabled by the +CONFIG_RFKILL_INPUT Kconfig option. + +rfkill-input is a rfkill-related events input layer handler. This handler will +listen to all rfkill key events and will change the rfkill state of the +wireless devices accordingly. With this option enabled userspace could either +do nothing or simply perform monitoring tasks. + +The rfkill-input module also provides EPO (emergency power-off) functionality +for all wireless transmitters. This function cannot be overridden, and it is +always active. rfkill EPO is related to *_RFKILL_ALL input layer events. + + +Important terms for the rfkill subsystem: + +In order to avoid confusion, we avoid the term "switch" in rfkill when it is +referring to an electronic control circuit that enables or disables a +transmitter. We reserve it for the physical device a human manipulates +(which is an input device, by the way): + +rfkill switch: + + A physical device a human manipulates. Its state can be perceived by + the kernel either directly (through a GPIO pin, ACPI GPE) or by its + effect on a rfkill line of a wireless device. + +rfkill controller: + + A hardware circuit that controls the state of a rfkill line, which a + kernel driver can interact with *to modify* that state (i.e. it has + either write-only or read/write access). + +rfkill line: + + An input channel (hardware or software) of a wireless device, which + causes a wireless transmitter to stop emitting energy (BLOCK) when it + is active. Point of view is extremely important here: rfkill lines are + always seen from the PoV of a wireless device (and its driver). + +soft rfkill line/software rfkill line: + + A rfkill line the wireless device driver can directly change the state + of. Related to rfkill_state RFKILL_STATE_SOFT_BLOCKED. + +hard rfkill line/hardware rfkill line: + + A rfkill line that works fully in hardware or firmware, and that cannot + be overridden by the kernel driver. The hardware device or the + firmware just exports its status to the driver, but it is read-only. + Related to rfkill_state RFKILL_STATE_HARD_BLOCKED. + +The enum rfkill_state describes the rfkill state of a transmitter: + +When a rfkill line or rfkill controller is in the RFKILL_STATE_UNBLOCKED state, +the wireless transmitter (radio TX circuit for example) is *enabled*. When the +it is in the RFKILL_STATE_SOFT_BLOCKED or RFKILL_STATE_HARD_BLOCKED, the +wireless transmitter is to be *blocked* from operating. + +RFKILL_STATE_SOFT_BLOCKED indicates that a call to toggle_radio() can change +that state. RFKILL_STATE_HARD_BLOCKED indicates that a call to toggle_radio() +will not be able to change the state and will return with a suitable error if +attempts are made to set the state to RFKILL_STATE_UNBLOCKED. + +RFKILL_STATE_HARD_BLOCKED is used by drivers to signal that the device is +locked in the BLOCKED state by a hardwire rfkill line (typically an input pin +that, when active, forces the transmitter to be disabled) which the driver +CANNOT override. + +Full rfkill functionality requires two different subsystems to cooperate: the +input layer and the rfkill class. The input layer issues *commands* to the +entire system requesting that devices registered to the rfkill class change +state. The way this interaction happens is not complex, but it is not obvious +either: + +Kernel Input layer: + + * Generates KEY_WWAN, KEY_WLAN, KEY_BLUETOOTH, SW_RFKILL_ALL, and + other such events when the user presses certain keys, buttons, or + toggles certain physical switches. + + THE INPUT LAYER IS NEVER USED TO PROPAGATE STATUS, NOTIFICATIONS OR THE + KIND OF STUFF AN ON-SCREEN-DISPLAY APPLICATION WOULD REPORT. It is + used to issue *commands* for the system to change behaviour, and these + commands may or may not be carried out by some kernel driver or + userspace application. It follows that doing user feedback based only + on input events is broken, as there is no guarantee that an input event + will be acted upon. + + Most wireless communication device drivers implementing rfkill + functionality MUST NOT generate these events, and have no reason to + register themselves with the input layer. Doing otherwise is a common + misconception. There is an API to propagate rfkill status change + information, and it is NOT the input layer. + +rfkill class: + + * Calls a hook in a driver to effectively change the wireless + transmitter state; + * Keeps track of the wireless transmitter state (with help from + the driver); + * Generates userspace notifications (uevents) and a call to a + notification chain (kernel) when there is a wireless transmitter + state change; + * Connects a wireless communications driver with the common rfkill + control system, which, for example, allows actions such as + "switch all bluetooth devices offline" to be carried out by + userspace or by rfkill-input. + + THE RFKILL CLASS NEVER ISSUES INPUT EVENTS. THE RFKILL CLASS DOES + NOT LISTEN TO INPUT EVENTS. NO DRIVER USING THE RFKILL CLASS SHALL + EVER LISTEN TO, OR ACT ON RFKILL INPUT EVENTS. Doing otherwise is + a layering violation. + + Most wireless data communication drivers in the kernel have just to + implement the rfkill class API to work properly. Interfacing to the + input layer is not often required (and is very often a *bug*) on + wireless drivers. + + Platform drivers often have to attach to the input layer to *issue* + (but never to listen to) rfkill events for rfkill switches, and also to + the rfkill class to export a control interface for the platform rfkill + controllers to the rfkill subsystem. This does NOT mean the rfkill + switch is attached to a rfkill class (doing so is almost always wrong). + It just means the same kernel module is the driver for different + devices (rfkill switches and rfkill controllers). + + +Userspace input handlers (uevents) or kernel input handlers (rfkill-input): + + * Implements the policy of what should happen when one of the input + layer events related to rfkill operation is received. + * Uses the sysfs interface (userspace) or private rfkill API calls + to tell the devices registered with the rfkill class to change + their state (i.e. translates the input layer event into real + action). + * rfkill-input implements EPO by handling EV_SW SW_RFKILL_ALL 0 + (power off all transmitters) in a special way: it ignores any + overrides and local state cache and forces all transmitters to the + RFKILL_STATE_SOFT_BLOCKED state (including those which are already + supposed to be BLOCKED). Note that the opposite event (power on all + transmitters) is handled normally. + +Userspace uevent handler or kernel platform-specific drivers hooked to the +rfkill notifier chain: + + * Taps into the rfkill notifier chain or to KOBJ_CHANGE uevents, + in order to know when a device that is registered with the rfkill + class changes state; + * Issues feedback notifications to the user; + * In the rare platforms where this is required, synthesizes an input + event to command all *OTHER* rfkill devices to also change their + statues when a specific rfkill device changes state. + + +=============================================================================== +3: Kernel driver guidelines + +Remember: point-of-view is everything for a driver that connects to the rfkill +subsystem. All the details below must be measured/perceived from the point of +view of the specific driver being modified. + +The first thing one needs to know is whether his driver should be talking to +the rfkill class or to the input layer. In rare cases (platform drivers), it +could happen that you need to do both, as platform drivers often handle a +variety of devices in the same driver. + +Do not mistake input devices for rfkill controllers. The only type of "rfkill +switch" device that is to be registered with the rfkill class are those +directly controlling the circuits that cause a wireless transmitter to stop +working (or the software equivalent of them), i.e. what we call a rfkill +controller. Every other kind of "rfkill switch" is just an input device and +MUST NOT be registered with the rfkill class. + +A driver should register a device with the rfkill class when ALL of the +following conditions are met (they define a rfkill controller): + +1. The device is/controls a data communications wireless transmitter; + +2. The kernel can interact with the hardware/firmware to CHANGE the wireless + transmitter state (block/unblock TX operation); + +3. The transmitter can be made to not emit any energy when "blocked": + rfkill is not about blocking data transmissions, it is about blocking + energy emission; + +A driver should register a device with the input subsystem to issue +rfkill-related events (KEY_WLAN, KEY_BLUETOOTH, KEY_WWAN, KEY_WIMAX, +SW_RFKILL_ALL, etc) when ALL of the folowing conditions are met: + +1. It is directly related to some physical device the user interacts with, to + command the O.S./firmware/hardware to enable/disable a data communications + wireless transmitter. + + Examples of the physical device are: buttons, keys and switches the user + will press/touch/slide/switch to enable or disable the wireless + communication device. + +2. It is NOT slaved to another device, i.e. there is no other device that + issues rfkill-related input events in preference to this one. -The system inside the kernel has been split into 2 separate sections: - 1 - RFKILL - 2 - RFKILL_INPUT + Please refer to the corner cases and examples section for more details. -The first option enables rfkill support and will make sure userspace will -be notified of any events through the input device. It also creates several -sysfs entries which can be used by userspace. See section "Userspace support". +When in doubt, do not issue input events. For drivers that should generate +input events in some platforms, but not in others (e.g. b43), the best solution +is to NEVER generate input events in the first place. That work should be +deferred to a platform-specific kernel module (which will know when to generate +events through the rfkill notifier chain) or to userspace. This avoids the +usual maintenance problems with DMI whitelisting. -The second option provides an rfkill input handler. This handler will -listen to all rfkill key events and will toggle the radio accordingly. -With this option enabled userspace could either do nothing or simply -perform monitoring tasks. +Corner cases and examples: ==================================== -2: Driver support -To build a driver with rfkill subsystem support, the driver should -depend on the Kconfig symbol RFKILL; it should _not_ depend on -RKFILL_INPUT. +1. If the device is an input device that, because of hardware or firmware, +causes wireless transmitters to be blocked regardless of the kernel's will, it +is still just an input device, and NOT to be registered with the rfkill class. -Unless key events trigger an interrupt to which the driver listens, polling -will be required to determine the key state changes. For this the input -layer providers the input-polldev handler. +2. If the wireless transmitter switch control is read-only, it is an input +device and not to be registered with the rfkill class (and maybe not to be made +an input layer event source either, see below). -A driver should implement a few steps to correctly make use of the -rfkill subsystem. First for non-polling drivers: +3. If there is some other device driver *closer* to the actual hardware the +user interacted with (the button/switch/key) to issue an input event, THAT is +the device driver that should be issuing input events. - - rfkill_allocate() - - input_allocate_device() - - rfkill_register() - - input_register_device() +E.g: + [RFKILL slider switch] -- [GPIO hardware] -- [WLAN card rf-kill input] + (platform driver) (wireless card driver) + +The user is closer to the RFKILL slide switch plaform driver, so the driver +which must issue input events is the platform driver looking at the GPIO +hardware, and NEVER the wireless card driver (which is just a slave). It is +very likely that there are other leaves than just the WLAN card rf-kill input +(e.g. a bluetooth card, etc)... + +On the other hand, some embedded devices do this: + + [RFKILL slider switch] -- [WLAN card rf-kill input] + (wireless card driver) + +In this situation, the wireless card driver *could* register itself as an input +device and issue rf-kill related input events... but in order to AVOID the need +for DMI whitelisting, the wireless card driver does NOT do it. Userspace (HAL) +or a platform driver (that exists only on these embedded devices) will do the +dirty job of issuing the input events. + + +COMMON MISTAKES in kernel drivers, related to rfkill: +==================================== + +1. NEVER confuse input device keys and buttons with input device switches. + + 1a. Switches are always set or reset. They report the current state + (on position or off position). + + 1b. Keys and buttons are either in the pressed or not-pressed state, and + that's it. A "button" that latches down when you press it, and + unlatches when you press it again is in fact a switch as far as input + devices go. + +Add the SW_* events you need for switches, do NOT try to emulate a button using +KEY_* events just because there is no such SW_* event yet. Do NOT try to use, +for example, KEY_BLUETOOTH when you should be using SW_BLUETOOTH instead. + +2. Input device switches (sources of EV_SW events) DO store their current state +(so you *must* initialize it by issuing a gratuitous input layer event on +driver start-up and also when resuming from sleep), and that state CAN be +queried from userspace through IOCTLs. There is no sysfs interface for this, +but that doesn't mean you should break things trying to hook it to the rfkill +class to get a sysfs interface :-) + +3. Do not issue *_RFKILL_ALL events by default, unless you are sure it is the +correct event for your switch/button. These events are emergency power-off +events when they are trying to turn the transmitters off. An example of an +input device which SHOULD generate *_RFKILL_ALL events is the wireless-kill +switch in a laptop which is NOT a hotkey, but a real switch that kills radios +in hardware, even if the O.S. has gone to lunch. An example of an input device +which SHOULD NOT generate *_RFKILL_ALL events by default, is any sort of hot +key that does nothing by itself, as well as any hot key that is type-specific +(e.g. the one for WLAN). + + +3.1 Guidelines for wireless device drivers +------------------------------------------ + +1. Each independent transmitter in a wireless device (usually there is only one +transmitter per device) should have a SINGLE rfkill class attached to it. + +2. If the device does not have any sort of hardware assistance to allow the +driver to rfkill the device, the driver should emulate it by taking all actions +required to silence the transmitter. + +3. If it is impossible to silence the transmitter (i.e. it still emits energy, +even if it is just in brief pulses, when there is no data to transmit and there +is no hardware support to turn it off) do NOT lie to the users. Do not attach +it to a rfkill class. The rfkill subsystem does not deal with data +transmission, it deals with energy emission. If the transmitter is emitting +energy, it is not blocked in rfkill terms. + +4. It doesn't matter if the device has multiple rfkill input lines affecting +the same transmitter, their combined state is to be exported as a single state +per transmitter (see rule 1). + +This rule exists because users of the rfkill subsystem expect to get (and set, +when possible) the overall transmitter rfkill state, not of a particular rfkill +line. + +Example of a WLAN wireless driver connected to the rfkill subsystem: +-------------------------------------------------------------------- + +A certain WLAN card has one input pin that causes it to block the transmitter +and makes the status of that input pin available (only for reading!) to the +kernel driver. This is a hard rfkill input line (it cannot be overridden by +the kernel driver). + +The card also has one PCI register that, if manipulated by the driver, causes +it to block the transmitter. This is a soft rfkill input line. + +It has also a thermal protection circuitry that shuts down its transmitter if +the card overheats, and makes the status of that protection available (only for +reading!) to the kernel driver. This is also a hard rfkill input line. + +If either one of these rfkill lines are active, the transmitter is blocked by +the hardware and forced offline. + +The driver should allocate and attach to its struct device *ONE* instance of +the rfkill class (there is only one transmitter). + +It can implement the get_state() hook, and return RFKILL_STATE_HARD_BLOCKED if +either one of its two hard rfkill input lines are active. If the two hard +rfkill lines are inactive, it must return RFKILL_STATE_SOFT_BLOCKED if its soft +rfkill input line is active. Only if none of the rfkill input lines are +active, will it return RFKILL_STATE_UNBLOCKED. -For polling drivers: +If it doesn't implement the get_state() hook, it must make sure that its calls +to rfkill_force_state() are enough to keep the status always up-to-date, and it +must do a rfkill_force_state() on resume from sleep. +Every time the driver gets a notification from the card that one of its rfkill +lines changed state (polling might be needed on badly designed cards that don't +generate interrupts for such events), it recomputes the rfkill state as per +above, and calls rfkill_force_state() to update it. + +The driver should implement the toggle_radio() hook, that: + +1. Returns an error if one of the hardware rfkill lines are active, and the +caller asked for RFKILL_STATE_UNBLOCKED. + +2. Activates the soft rfkill line if the caller asked for state +RFKILL_STATE_SOFT_BLOCKED. It should do this even if one of the hard rfkill +lines are active, effectively double-blocking the transmitter. + +3. Deactivates the soft rfkill line if none of the hardware rfkill lines are +active and the caller asked for RFKILL_STATE_UNBLOCKED. + +=============================================================================== +4: Kernel API + +To build a driver with rfkill subsystem support, the driver should depend on +(or select) the Kconfig symbol RFKILL; it should _not_ depend on RKFILL_INPUT. + +The hardware the driver talks to may be write-only (where the current state +of the hardware is unknown), or read-write (where the hardware can be queried +about its current state). + +The rfkill class will call the get_state hook of a device every time it needs +to know the *real* current state of the hardware. This can happen often. + +Some hardware provides events when its status changes. In these cases, it is +best for the driver to not provide a get_state hook, and instead register the +rfkill class *already* with the correct status, and keep it updated using +rfkill_force_state() when it gets an event from the hardware. + +There is no provision for a statically-allocated rfkill struct. You must +use rfkill_allocate() to allocate one. + +You should: - rfkill_allocate() - - input_allocate_polled_device() + - modify rfkill fields (flags, name) + - modify state to the current hardware state (THIS IS THE ONLY TIME + YOU CAN ACCESS state DIRECTLY) - rfkill_register() - - input_register_polled_device() -When a key event has been detected, the correct event should be -sent over the input device which has been registered by the driver. +The only way to set a device to the RFKILL_STATE_HARD_BLOCKED state is through +a suitable return of get_state() or through rfkill_force_state(). -==================================== -3: Userspace support +When a device is in the RFKILL_STATE_HARD_BLOCKED state, the only way to switch +it to a different state is through a suitable return of get_state() or through +rfkill_force_state(). + +If toggle_radio() is called to set a device to state RFKILL_STATE_SOFT_BLOCKED +when that device is already at the RFKILL_STATE_HARD_BLOCKED state, it should +not return an error. Instead, it should try to double-block the transmitter, +so that its state will change from RFKILL_STATE_HARD_BLOCKED to +RFKILL_STATE_SOFT_BLOCKED should the hardware blocking cease. -For each key an input device will be created which will send out the correct -key event when the rfkill key has been pressed. +Please refer to the source for more documentation. + +=============================================================================== +5: Userspace support + +rfkill devices issue uevents (with an action of "change"), with the following +environment variables set: + +RFKILL_NAME +RFKILL_STATE +RFKILL_TYPE + +The ABI for these variables is defined by the sysfs attributes. It is best +to take a quick look at the source to make sure of the possible values. + +It is expected that HAL will trap those, and bridge them to DBUS, etc. These +events CAN and SHOULD be used to give feedback to the user about the rfkill +status of the system. + +Input devices may issue events that are related to rfkill. These are the +various KEY_* events and SW_* events supported by rfkill-input.c. + +******IMPORTANT****** +When rfkill-input is ACTIVE, userspace is NOT TO CHANGE THE STATE OF AN RFKILL +SWITCH IN RESPONSE TO AN INPUT EVENT also handled by rfkill-input, unless it +has set to true the user_claim attribute for that particular switch. This rule +is *absolute*; do NOT violate it. +******IMPORTANT****** + +Userspace must not assume it is the only source of control for rfkill switches. +Their state CAN and WILL change due to firmware actions, direct user actions, +and the rfkill-input EPO override for *_RFKILL_ALL. + +When rfkill-input is not active, userspace must initiate a rfkill status +change by writing to the "state" attribute in order for anything to happen. + +Take particular care to implement EV_SW SW_RFKILL_ALL properly. When that +switch is set to OFF, *every* rfkill device *MUST* be immediately put into the +RFKILL_STATE_SOFT_BLOCKED state, no questions asked. The following sysfs entries will be created: name: Name assigned by driver to this key (interface or driver name). type: Name of the key type ("wlan", "bluetooth", etc). - state: Current state of the key. 1: On, 0: Off. + state: Current state of the transmitter + 0: RFKILL_STATE_SOFT_BLOCKED + transmitter is forced off, but one can override it + by a write to the state attribute; + 1: RFKILL_STATE_UNBLOCKED + transmiter is NOT forced off, and may operate if + all other conditions for such operation are met + (such as interface is up and configured, etc); + 2: RFKILL_STATE_HARD_BLOCKED + transmitter is forced off by something outside of + the driver's control. One cannot set a device to + this state through writes to the state attribute; claim: 1: Userspace handles events, 0: Kernel handles events Both the "state" and "claim" entries are also writable. For the "state" entry -this means that when 1 or 0 is written all radios, not yet in the requested -state, will be will be toggled accordingly. +this means that when 1 or 0 is written, the device rfkill state (if not yet in +the requested state), will be will be toggled accordingly. + For the "claim" entry writing 1 to it means that the kernel no longer handles key events even though RFKILL_INPUT input was enabled. When "claim" has been set to 0, userspace should make sure that it listens for the input events or -check the sysfs "state" entry regularly to correctly perform the required -tasks when the rkfill key is pressed. +check the sysfs "state" entry regularly to correctly perform the required tasks +when the rkfill key is pressed. + +A note about input devices and EV_SW events: + +In order to know the current state of an input device switch (like +SW_RFKILL_ALL), you will need to use an IOCTL. That information is not +available through sysfs in a generic way at this time, and it is not available +through the rfkill class AT ALL. |